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American Journal of Neuroradiology current issue

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Heit, J. J., Rabinov, J. D. · Monday, June 13, 2016, 23:11

Tags: Imaging, Neurology

American Journal of Neuroradiology current issue

Nonmotor Functions of the Cerebellum: An Introduction [research-article]

Klein, A. P., Ulmer, J. L., Quinet, S. A., Mathews, V., Mark, L. P. · Monday, June 13, 2016, 23:11

Tags: Imaging, Neurology

American Journal of Neuroradiology current issue

Interrogating the Functional Correlates of Collateralization in Patients with Intracranial Stenosis Using Multimodal Hemodynamic Imaging [ADULT BRAIN]

Roach, B. A., Donahue, M. J., Davis, L. T., Faraco, C. C., Arteaga, D., Chen, S.- C., Ladner, T. R., Scott, A. O., Strother, M. K. · Monday, June 13, 2016, 23:11

BACKGROUND AND PURPOSE:

The importance of collateralization for maintaining adequate cerebral perfusion is increasingly recognized. However, measuring collateral flow noninvasively has proved elusive. The aim of this study was to assess correlations among baseline perfusion and arterial transit time artifacts, cerebrovascular reactivity, and the presence of collateral vessels on digital subtraction angiography.

MATERIALS AND METHODS:

The relationship between the presence of collateral vessels on arterial spin-labeling MR imaging and DSA was compared with blood oxygen level–dependent MR imaging measures of hypercapnic cerebrovascular reactivity in patients with symptomatic intracranial stenosis (n = 18). DSA maps were reviewed by a neuroradiologist and assigned the following scores: 1, collaterals to the periphery of the ischemic site; 2, complete irrigation of the ischemic bed via collateral flow; and 3, normal antegrade flow. Arterial spin-labeling maps were scored according to the following: 0, low signal; 1, moderate signal with arterial transit artifacts; 2, high signal with arterial transit artifacts; and 3, normal signal.

RESULTS:

In regions with normal-to-high signal on arterial spin-labeling, collateral vessel presence on DSA strongly correlated with declines in cerebrovascular reactivity (as measured on blood oxygen level–dependent MR imaging, P < .001), most notably in patients with nonatherosclerotic disease. There was a trend toward increasing cerebrovascular reactivity with increases in the degree of collateralization on DSA (P = .082).

CONCLUSIONS:

Collateral vessels may have fundamentally different vasoreactivity properties from healthy vessels, a finding that is observed most prominently in nonatherosclerotic disease and, to a lesser extent, in atherosclerotic disease.

Tags: Imaging, Neurology

American Journal of Neuroradiology current issue

Differentiating Pediatric Rhabdomyosarcoma and Langerhans Cell Histiocytosis of the Temporal Bone by Imaging Appearance [HEAD & NECK]

Chevallier, K. M., Wiggins, R. H., Quinn, N. A., Gurgel, R. K. · Monday, June 13, 2016, 23:11

BACKGROUND AND PURPOSE:

Rhabdomyosarcoma and Langerhans cell histiocytosis are malignant lesions that can affect the skull base with similar radiographic characteristics on CT and MR imaging. We hypothesized that location within the temporal bone determined radiographically can provide useful adjunctive information in differentiating these distinct neoplasms.

MATERIALS AND METHODS:

We identified patients with Langerhans cell histiocytosis and rhabdomyosarcoma by using an imaging data base and International Classification of Diseases, Ninth Revision codes at a tertiary care academic medical center. Cross-sectional images were reviewed by a neurotologist and neuroradiologist, who evaluated the location of the lesions and scored each subsite—middle ear, mastoid, petrous apex, retrosigmoid/posterior fossa—on a scale of 0 (no involvement), 1 (partial), or 2 (complete involvement).

RESULTS:

We identified 12 patients representing 14 cases of Langerhans cell histiocytosis, and 9 patients representing 9 cases of rhabdomyosarcoma. For patients with Langerhans cell histiocytosis, mastoid involvement was rated 23/28 (82%) compared with 6/18 (33%) with rhabdomyosarcoma (P = .001). Langerhans cell histiocytosis was present in only the anterior portion of the temporal bone (petrous apex and middle ear) in 1 case (7.1%) and in the anterior portion of the temporal bone only in 5/9 (55%) cases of rhabdomyosarcoma (P = .018). The cortical bone was more commonly involved in Langerhans cell histiocytosis, 11/28 (39%) of cases compared with 2/18 (11%) cases in rhabdomyosarcoma (P < .05).

CONCLUSIONS:

These results indicate that lesions involving only the anterior portion of the temporal bone (petrous apex and middle ear) are more likely to be rhabdomyosarcoma. Lesions involving the mastoid are more likely to be Langerhans cell histiocytosis. This difference in primary location may be helpful in predicting the pathology of these lesions on the basis of imaging.

Tags: Imaging, Neurology

Acta Radiologica current issue

Roentgenological Examinations of the Motility of the Stomach in Healthy Individuals during Rest and Motion

Nielsen, A. A. · Monday, June 13, 2016, 19:59

Tags: Imaging

Acta Radiologica current issue

The Definite Form of the Coxa Plana

Waldenström, H. · Monday, June 13, 2016, 19:59

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Acta Radiologica current issue

'Classic papers in this issue of Acta Radiologica

Skjennald, A. · Monday, June 13, 2016, 19:59

Tags: Imaging

Acta Radiologica current issue

Objective measurement of the distal resection margin by MRI of the fresh and fixed specimen after partial mesorectal excision for rectal cancer: 5 cm is not just 5 cm and depends on when measured

Bondeven, P., Hagemann-madsen, R. H., Bro, L., Moran, B. J., Laurberg, S., Pedersen, B. G. · Monday, June 13, 2016, 19:59

Background

Most studies have directly established the optimal perioperative in situ clearance margin in surgery for rectal cancer from the histologically observed extent of distal spread, neglecting the tissue variability that occurs after resection and fixation of the rectal specimen.

Purpose

To measure the length of the distal resection margin in the fresh and fixed specimen following partial mesorectal excision for rectal cancer using magnetic resonance imaging (MRI) to document tissue shrinkage after surgical removal and fixation.

Material and Methods

The length of the distal resection margin was measured by MRI of the fresh and fixed specimen and at histopathological examination of the fixed specimen in 10 patients who underwent surgery for upper rectal cancer. In addition, tissue shrinkage was estimated by measuring the total length of the fresh and fixed specimen and distance from the peritoneal reflection anteriorly to the distal cut edge of the specimen.

Results

Measured by MRI, the distal resection margin was in the range of 0.6–10.2 cm (mean, 4.6 cm) in the fresh specimen, and 0.5–6.2 cm (mean, 3.2 cm) in the fixed specimen. The tissue shrinkage ratio was a mean of 69% (interquartile range, 61–77%). Taking all ratios from MRI and histopathological examination of tissue shrinkage into account, the collective tissue shrinkage ratio was 70% (95% confidence interval, 67–73%)

Conclusion

The length of the distal resection margin was reduced by 30% after surgical removal and fixation of the specimen.

Tags: Imaging

Acta Radiologica current issue

Idiopathic granulomatous mastitis: magnetic resonance imaging findings with diffusion MRI

Aslan, H., Pourbagher, A., Colakoglu, T. · Monday, June 13, 2016, 19:59

Background

Idiopathic granulomatous mastitis (IGM) is a rare benign breast disease with unknown etiology which can mimic breast carcinoma, both clinically and radiologically. Magnetic resonance imaging (MRI) findings of IGM have been previously described; however there is no study evaluating diffusion-weighted MRI findings of IGM.

Purpose

To analyze conventional, dynamic contrast-enhanced, and diffusion-weighted MRI signal characteristics of IGM by comparing it with the contralateral normal breast parenchyma.

Material and Methods

A total of 39 patients were included in the study. On dynamic contrast-enhanced MRI, the distribution and enhancement patterns of the lesions were evaluated. We also detected the frequencies of involving quadrants, retroareolar involvement, accompanying abscess, and skin edema. T2-weighted (T2W) and STIR signal intensities and both mean and minimum apparent diffusion coefficient (ADC) values were compared with the contralateral normal parenchyma.

Results

IGM showed significantly lower mean and minimum ADC values when compared with the normal parenchyma. Signal intensities on T2W and STIR sequences of the lesion were significantly higher than the normal parenchyma. On dynamic contrast-enhanced MRI, 7.7% of the patients had mass-like contrast enhancement, 92.3% of the patients had non-mass-like contrast enhancement. Abscess was positive in 33.3% of the patients.

Conclusion

As a result, IGM showed commonly non-mass-like lesions with restricted diffusion. Although it is a benign pathology, it may show clustered ring-like enhancement like malignant lesions.

Tags: Imaging

Acta Radiologica current issue

Breast parenchymal signal enhancement ratio at preoperative magnetic resonance imaging: association with early recurrence in triple-negative breast cancer patients

Park, V. Y., Kim, E.-k., Kim, M. J., Yoon, J. H., Moon, H. J. · Monday, June 13, 2016, 19:59

Background

The signal enhancement ratio (SER) of surrounding non-tumor parenchyma at breast magnetic resonance imaging (MRI) can be helpful in breast cancer patients, but has not been investigated in patients with triple negative breast cancer (TNBC).

Purpose

To investigate the association between background parenchymal SER around the tumor on preoperative dynamic contrast-enhanced MRI with recurrence-free survival in patients with TNBC.

Material and Methods

Between April 2012 and May 2013, 71 TNBC patients who underwent preoperative MRI were included. SER values were calculated from regions of interest placed in the breast parenchyma around the tumor. Cox proportional hazards models were used to determine associations between MRI variables, clinical-pathologic variables, and recurrence-free survival.

Results

Recurrence occurred in 8.5% (6/71) of patients. At univariate analysis, a higher SER around the tumor, larger tumor size, lymphovascular invasion, lymph node metastasis, receipt of neoadjuvant chemotherapy, receipt of total mastectomy, and not receiving adjuvant chemotherapy were associated with worse recurrence-free survival. At multivariate analysis of preoperative variables, a higher SER around the tumor was independently associated with worse recurrence-free survival (hazard ratio [HR] = 7.072,P = 0.003 for SER1; HR = 6.268, P = 0.006 for SER2; HR = 3.004, P = 0.039 for SER3).

Conclusion

Higher SER around the tumor at preoperative dynamic contrast-enhanced MRI is an independent predictor for recurrence in TNBC patients.

Tags: Imaging

Acta Radiologica current issue

Radiologic evaluation of lumps in the male breast

Tangerud, A., Potapenko, I., Skjerven, H. K., Stensrud, M. J. · Monday, June 13, 2016, 19:59

Background

Gynecomastia has a typical appearance on mammography, and occurs frequently in men. However, imaging is often performed on men with breast lumps to exclude breast cancer, which only comprises 1% of male breast masses.

Purpose

To assess whether ultrasound and fine needle aspiration cytology (FNAC) are necessary investigations when mammograms show classical gynecomastia.

Material and Methods

We have retrospectively collected data on male patients referred for mammography during the period 2011–2013 (a total of 539 patients). All radiological images were re-read, and descriptions of ultrasound images were reviewed. Clinical information supplied with the original referrals was assessed, along with pathology and cytology reports.

Results

Among the 539 male patients who underwent mammography, 483 were also examined with ultrasound, and 335 were further evaluated with FNAC. Mammograms showed gynecomastia in 350 patients, and among these subjects ultrasound was performed in 340 (97%), FNAC in 261 (75%), and core biopsies in four (1%) patients. The diagnosis gynecomastia was unchanged in all patients who underwent FNAC or biopsy. Malignant tumors were found in eight patients, six of which were invasive ductal carcinomas.

Conclusion

In patients with a classical appearance of gynecomastia on mammography, supplemental ultrasound, FNAC, or biopsy is superfluous and contributes to unnecessary costs.

Tags: Imaging

Acta Radiologica current issue

Lesions with unclear malignant potential (B3) after minimally invasive breast biopsy: evaluation of vacuum biopsies performed in Switzerland and recommended further management

Saladin, C., Haueisen, H., Kampmann, G., Oehlschlegel, C., Seifert, B., Rageth, L., Rageth, C., Stadlmann, S., Kubik-huch, R. A., On Behalf Of The Mibb Group · Monday, June 13, 2016, 19:59

Background

Histopathological B3 lesions after minimal invasive breast biopsy (VABB) are a particular challenge for the clinician, as there are currently no binding recommendations regarding the subsequent procedure.

Purpose

To analyze all B3 lesions, diagnosed at VABB and captured in the national central Swiss MIBB database and to provide a data basis for further management in this subgroup of patients.

Material and Methods

All 9,153 stereotactically, sonographically, or magnetic resonance imaging (MRI)-guided vacuum-assisted breast biopsies, performed in Switzerland between 2009 and 2011, captured in a central database, were evaluated. The rate of B3 lesions and the definitive pathological findings in patients who underwent surgical resection were analyzed.

Results

The B3 rate was 17.0% (1532 of 9000 biopsies with B classification). Among the 521 lesions with a definitive postoperative diagnosis, the malignancy rate (invasive carcinoma or DCIS) was 21.5%. In patients with atypical ductal hyperplasia, papillary lesions, flat epithelial atypia, lobular neoplasia, and radial scar diagnosed by VABB, the malignancy rates were 25.9%, 3.1%, 18.3%, 26.4%, and 11.1%, respectively.

Conclusion

B3 lesions, comprising 17%, of all analyzed biopsies, were common and the proportion of malignancies in those lesions undergoing subsequent surgical excision was high (21.5%).

Tags: Imaging

Acta Radiologica current issue

Diagnostic performance and radiation dose of lower extremity CT angiography using a 128-slice dual source CT at 80 kVp and high pitch

Kim, J. W., Choo, K. S., Jeon, U. B., Kim, T. U., Hwang, J. Y., Yeom, J. A., Jeong, H. S., Choi, Y. Y., Nam, K. J., Kim, C. W., Jeong, D. W., Lim, S. J. · Monday, June 13, 2016, 19:59

Background

Multi-detector computed tomography (MDCT) angiography is now used for the diagnosing patients with peripheral arterial disease. The dose of radiation is related to variable factors, such as tube current, tube voltage, and helical pitch.

Purpose

To assess the diagnostic performance and radiation dose of lower extremity CT angiography (CTA) using a 128-slice dual source CT at 80 kVp and high pitch in patients with critical limb ischemia (CLI).

Material and Methods

Twenty-eight patients (mean, 64.1 years; range, 39–80 years) with CLI were enrolled in this retrospective study and underwent CTA using a 128-slice dual source CT at 80 kVp and high pitch and subsequent intra-arterial digital subtraction angiography (DSA), which was used as a reference standard for assessing diagnostic performance.

Results

For arterial segments with significant disease (>50% stenosis), overall sensitivity, specificity, and accuracy of lower extremity CTA were 94.8% (95% CI, 91.7–98.0%), 91.5% (95% CI, 87.7–95.2%), and 93.1% (95% CI, 90.6–95.6%), respectively, and its positive and negative predictive values were 91.0% (95% CI, 87.1–95.0%), and 95.1% (95% CI, 92.1–98.1%), respectively. Mean radiation dose delivered to lower extremities was 266.6 mGy.cm.

Conclusion

Lower extremity CTA using a 128-slice dual source CT at 80 kVp and high pitch was found to have good diagnostic performance for the assessment of patients with CLI using an extremely low radiation dose.

Tags: Imaging

Acta Radiologica current issue

Optimization of scan timing for aortic computed tomographic angiography using the test bolus injection technique

Hoshino, T., Ichikawa, K., Hara, T., Terakawa, S., Hosomi, K., Nishimura, K., Takayama, K. · Monday, June 13, 2016, 19:59

Background

With fast computed tomography (CT), it is possible for the scanning to outpace the contrast medium bolus during aortic CT angiography (CTA).

Purpose

To evaluate the effectiveness of a new method for reducing the risk of outpacing in which the scan start timing (ST) and speed can be estimated from the peak enhancement time measured at the femoral artery using a single test-bolus injection (femoral artery test injection method [FTI method]).

Material and Methods

In 30 cases of aortic CTA, we measured the time to peak enhancement at the femoral artery (T_PF) and the ascending aorta (T_PA) with test-bolus injection performed twice in each examination. From the resultant linear relationship between T_PF and transit time (TT= T_PF – T_PA), we developed a method for determining the ST and TT from T_PF. One hundred patients were assigned to two groups: FTI and bolus tracking (BT), each with 50 patients. CT values were measured in main vessels (ascending aorta, descending aorta, femoral artery). The CT values of the vessels and the rate of cases with more than 300 HU (good cases) were compared between the two groups.

Results

The enhancement in the FTI method was significantly higher than that of the BT method (average CT values: FTI, 388.3 ± 52.4; BT, 281.2 ± 59.1; P < 0.001). The rates of good cases for FTI and BT were 86.0% and 46.0%, respectively.

Conclusion

The FTI method was very effective in reducing the risk of outpacing of the contrast medium transit in aortic CTA without the need for an additional contrast medium dose.

Tags: Imaging

Acta Radiologica current issue

MRI and CT imaging characteristics of myoepithelioma of the parotid gland

Ding, J., Wang, W., Peng, W., Zhou, X., Chen, T. · Monday, June 13, 2016, 19:59

Background

Myoepithelioma is a rare tumor of the salivary gland and only few reports have focused on its imaging characteristics.

Purpose

To characterize the magnetic resonance imaging (MRI) and computed tomography (CT) characteristics of myoepithelioma of the parotid gland.

Material and Methods

We retrospectively analyzed the MRI and CT findings of nine patients with myoepithelioma in the parotid gland as demonstrated by pathologic analysis. The MRI and CT findings were analyzed regarding the tumor position, size, marginal morphology, and degree and patterns of enhancement.

Results

Unilocular and multilocular tumors were found in seven cases (7/9, 77.8%) and two cases (2/9, 22.2%), respectively. Most of the tumors were located in the superficial lobe (6/9, 66.7%) and abutted the capsule of the parotid gland (7/9, 77.8%). Six of the seven unilocular tumors were round. Most of the tumors displayed smooth contours (6/9, 66.7%) and well-defined margins (5/9, 55.6%). Four of five tumors (80%) display the capsule on T2-weighted (T2W) and contrast-enhanced T1-weighted (T1W) imaging. All five examined tumors exhibited homogeneous intermediate signal intensity on T1W imaging and high signal intensity on T2W imaging. On contrast-enhanced T1W imaging, the tumors displayed homogeneous (n = 4) or heterogeneous (n = 1) moderate to marked contrast enhancement. Based on the enhanced CT scans, four tumors exhibited moderate homogeneous (n = 2) or heterogeneous (n = 2) contrast enhancement.

Conclusion

Myoepitheliomas are characterized as small, unilocular, round tumors with smooth contours that are located in the superficial lobe and abut the capsule of the parotid gland, display the capsule on T2W and contrast-enhanced T1W imaging, and exhibit homogeneous signal intensities or densities based on MRI and CT.

Tags: Imaging

Acta Radiologica current issue

Combination of radiofrequency ablation with transarterial chemoembolization for treatment of hepatocellular carcinoma: experience from a Danish tertiary liver center

Bharadwaz, A., Bak-fredslund, K. P., Villadsen, G. E., Nielsen, J. E., Simonsen, K., Sandahl, T. D., Gronbaek, H., Nielsen, D. T. · Monday, June 13, 2016, 19:59

Background

Recent studies have shown that the combination of radiofrequency ablation (RFA) and transarterial chemoembolization (TACE) for unresectable hepatocellular carcinoma (HCC) may offer a survival advantage compared to monotherapy.

Purpose

To study the effectiveness of combination therapy with RFA and TACE compared to that of TACE alone in a Scandinavian tertiary liver cancer center.

Material and Methods

A retrospective study of the patients treated with combination therapy vis-à-vis TACE alone from June 2007 to November 2012 was performed. Eighteen patients were treated with a combination of RFA and TACE with an interval of 1–4 days between the treatments. For comparison, a group of 18 patients treated with TACE as monotherapy in the same time period was matched with the combination group by demographic data, tumor characteristics, biochemical and clinical parameters, and performance status (PS).

Results

Each group consisted of 14 patients with cirrhosis and four without. There were no significant differences between the groups regarding age, gender, tumor characteristics, causes of cirrhosis, levels of bilirubin, creatinine, prothrombin time, Child Pugh score, or World Health Organization (WHO) performance status. The median survival of patients in the RFA + TACE combination group was 586 days compared to 296 days in the control group. The difference was not statistically significant (P = 0.26). However, when we stratified the data for cirrhosis and WHO performance status, patients in the combination group had significantly better survival (P = 0.024).

Conclusion

Combination therapy with RFA and TACE for unresectable HCC, compared to TACE alone, may offer a survival benefit for a selected group of patients with HCC.

Tags: Imaging

Acta Radiologica current issue

The phase value of putamen measured by susceptibility weighted images in Parkinsons disease and in other forms of Parkinsonism: a correlation study with F18 FP-CIT PET

Kwon, G. H., Jang, J., Choi, H. S., Hwang, E.-j., Jung, S.-l., Ahn, K.-j., Kim, B.-s., Yoo, I. R., Kim, S. H., Haacke, E. M. · Monday, June 13, 2016, 19:59

Background

Iron deposition of basal ganglia in Parkinson's disease (PD) can be measured using susceptibility weighted images (SWI) on magnetic resonance imaging (MRI). Fluoropropyl carbomethoxy-3b-4-iodophenyltropane (F18 FP-CIT) positron emission tomography (PET) has been used to differentiate Parkinsonism.

Purpose

To compare SWI phase values in Parkinsonian syndrome and age-matched control and to correlate them with F18 FP-CIT PET.

Material and Methods

Retrospectively, patients with Parkinsonian movement disorder (n = 62) and age-matched control (n = 16) were enrolled. Mean phase values on SWI were measured by region of interest (ROI) in putamens and caudate heads. Mean standardized uptake value (SUV) on F18 FP-CIT were measured in the same ROIs of PD (n = 40) and other forms of Parkinsonism (n = 22). A statistical analysis was performed to compare the phase values and SUVs and to correlate them between groups.

Results

The putaminal mean phase values were higher in Parkinsonism than in the control (P ≤0.001). There was no difference of phase value in caudate head among the groups. Also, the mean phase value of putamen between PD and other forms of Parkinsonism was not different. Mean SUV of F18 FP-CIT in the putamen was lower in PD than other forms of Parkinsonism (P ≤ 0.014). However, there was no significant correlation between phase values and mean SUV (P > 0.05).

Conclusion

The putaminal phase value was higher than in Parkinsonian syndrome than in the age-matched controls. F18 FP-CIT PET/CT showed different tracer activity between PD and other forms of Parkinsonism. However, no correlation between phase and SUV values was discovered.

Tags: Imaging

Acta Radiologica current issue

Investigation of the functional difference between the pathological itching and neuropathic pain-induced rat brain using manganese-enhanced MRI

Jeong, K.-y., Kim, H. M., Kang, J.-h. · Monday, June 13, 2016, 19:59

Background

There is a remarkable similarity in the central sensitization of itch and pain. However, the interactions between itch and pain are only partially understood.

Purpose

To investigate the functional activity of cerebral regions to provide clear information on the neuronal pathways related to both pathological itching (PI) and neuropathic pain (NP).

Material and Methods

Sprague-Dawley rats were used in this study. PI was induced via neonatal capsaicin treatment, and scratching behavior was counted. NP was induced via lumbar spinal nerve 5 (L5) ligation, and mechanical allodynia was measured. The activated cerebral regions in the control, PI, and NP rats were measured using a 4.7 T magnetic resonance imaging (MRI) system and manganese-enhanced MRI (MEMRI). Subsequently, the cerebral activation regions were identified, and the signal intensity was compared.

Results

Cerebral activities of the PI-induced rats were found in three regions –7.10 and –4.20 mm, and two regions –2.45 mm from the bregma. In the NP-induced rats, cerebral activities were found in two regions 7.10 and –2.45 mm, and one region –4.20 mm from the bregma. Comparing the PI and NP rats, the cerebral activities were different in one region –7.10 mm and –2.45 mm, and two regions –4.20 mm from the bregma. The different regions were the midbrain area, the geniculate complex, the hypothalamic area, and the amygdala area.

Conclusion

Our MEMRI investigation indicates functionally different activity of cerebral regions due to the effect of PI or NP. These findings provide clear information of the signal transduction in the brain regarding PI or NP that share a similar neuronal pathway.

Tags: Imaging

Acta Radiologica current issue

Value of diffusion-weighted MRI in diagnosis of uterine cervical cancer: a prospective study evaluating the benefits of DWI compared to conventional MR sequences in a 3T environment

Exner, M., Kühn, A., Stumpp, P., Höckel, M., Horn, L.-c., Kahn, T., Brandmaier, P. ·Monday, June 13, 2016, 19:59

Background

Imaging of cervical carcinoma remains challenging as local infiltration of surrounding tissues cannot always be discriminated safely. New imaging techniques, like diffusion-weighted imaging (DWI) have emerged, which could lead to a more sensitive tumor detection.

Purpose

To evaluate the benefits of DWI for determination of size, local infiltration, and tumor grading, in patients with primary and recurrent cervical cancer.

Material and Methods

In this prospective, study we enrolled 50 patients with primary (n = 35) and recurrent (n = 15) tumors. All patients underwent 3T magnetic resonance imaging (MRI) including conventional (e.g. T1/T2 ± fs ± contrast) sequences and DWI (b-values of 0, 50, 400, 800 s/mm²). All images were analyzed by three readers with different experience levels (1, 3, 6 years), who compared image quality, tumor delineation, dimensions, local infiltration, lymph node involvement, and quantified ADC values compared to the histopathological grading.

Results

Additional use of DWI resulted in significantly better (P < 0.001) tumor delineation for the least experienced reader, but not for experienced readers. Tumor dimensions were assessed almost equally (P > 0.05) in conventional sequences and DWI. Use of DWI led to an increase in sensitivity of infiltrated adjacent tissue (from 86% to 90%) and detection of lymph node metastases (from 47% to 67%). Quantitative assessment of carcinomas showed lower ADC values (P < 0.001) with significant inverse correlations between different grading levels.

Conclusion

Our study demonstrates the overall benefits using DWI in 3T MRI resulting in a higher reader confidence, sensitivity of tissue infiltration, and tumor-grading for cervical cancer.

Tags: Imaging

Acta Radiologica current issue

Susceptibility-weighted magnetic resonance imaging for the evaluation of deep infiltrating endometriosis: preliminary results

Cimsit, C., Yoldemir, T., Guclu, M., Akpinar, I. N. · Monday, June 13, 2016, 19:59

Background

Knowledge of the precise sites of deep infiltrating endometriosis (DIE) lesions is essential for preoperative workup and treatment. Susceptibility-weighted imaging (SWI) has high sensitivity for blood products and have recently been applied in abdominal imaging.

Purpose

To determine the value of SWI in the diagnosis of DIE.

Material and Methods

Forty-three clinically suspected DIE patients with sonographically diagnosed ovarian endometriomas who had tenderness or palpable nodule(s) on rectovaginal examination were referred to pelvic magnetic resonance imaging (MRI) including SWI. Two patients were excluded from the study because of low quality of SWI series. Twenty-eight patients who were offered laparoscopic endometriosis surgery (LES) preferred medical treatment over surgical approach. Thirteen out of 41 participants had LES. Lesions were evaluated for their locations, signal intensities on T1-weighted (T1W) and T2-weighted (T2W) images, and presence of signal voids on SWI using 3T MRI and correlated with LES findings.

Results

A total of 18 endometriosis foci were laparoscopically removed from 13 patients. DIE lesions removed at laparoscopy were located at the uterosacral ligament (9/18), rectovaginal region (4/18), retrocervical region (2/18), and fallopian tubes (3/18). Eleven out of 18 (61%) DIE foci were detected by their high-signal intensities on T1W images whereas 16 out of 18 (89%) DIE foci were detected by signal voids on SWI.

Conclusion

SWI imaging with its high sensitivity to blood products, contributes to the diagnosis of DIE by depicting different phases of hemorrhage not seen by conventional MRI sequences.

Tags: Imaging

Acta Radiologica current issue

Predictive factors for complete renal tumor ablation using RFA

Acosta Ruiz, V., Lönnemark, M., Brekkan, E., Dahlman, P., Wernroth, L., Magnusson, A. · Monday, June 13, 2016, 19:59

Background

Radiofrequency ablation (RFA) can be used to treat renal masses in patients where surgery is preferably avoided. As tumor size and location can affect ablation results, procedural planning needs to identify these factors to limit treatment to a single session and increase ablation success.

Purpose

To identify factors that may affect the primary efficacy of complete renal tumor ablation with radiofrequency after a single session.

Material and Methods

Percutaneous RFA (using an impedance based system) was performed using computed tomography (CT) guidance. Fifty-two renal tumors (in 44 patients) were retrospectively studied (median follow-up, 7 months). Data collection included patient demographics, tumor data (modified Renal Nephrometry Score, histopathological diagnosis), RFA treatment data (electrode placement), and follow-up results (tumor relapse). Data were analyzed through generalized estimating equations.

Results

Primary efficacy rate was 83%. Predictors for complete ablation were optimal electrode placement (P = 0.002, OR = 16.67) and increasing distance to the collecting system (P = 0.02, OR = 1.18). Tumor size was not a predictor for complete ablation (median size, 24 mm; P = 0.069, OR = 0.47), but all tumors ≤2 cm were completely ablated. All papillary tumors and oncocytomas were completely ablated in a single session; the most common incompletely ablated tumor type was clear cell carcinoma (6 of 9).

Conclusion

Optimal electrode placement and a long distance from the collecting system are associated with an increased primary efficacy of renal tumor RFA. These variables need to be considered to increase primary ablation success. Further studies are needed to evaluate the effect of RFA on histopathologically different renal tumors.

Tags: Imaging

Acta Radiologica current issue

CT and MRI imaging features and long-term follow-up of adult Wilms tumor

Wu, J., Zhu, Q., Zhu, W., Chen, W. · Monday, June 13, 2016, 19:59

Background

Only few previous case reports have been found focusing on the imaging findings of adult Wilms' tumor (WT).

Purpose

To characterize multislice computed tomography (MSCT), magnetic resonance imaging (MRI) characteristics, and follow-up results of adult WT.

Material and Methods

Sixteen patients with WT were studied retrospectively. MSCT and MRI were undertaken to investigate the tumor characteristics.

Results

Tumors (mean diameter, 13.1 ± 4.5 cm) exhibited an expansible appearance and disrupted the reniform contour (16/16), cystic components (16/16), curvilinear calcification (1/16), poorly marginated (2/16), hemorrhage (16/16), displacement of renal pelvis or calyx (13/16), and had lymph node or distal metastases (5/16). Attenuation of WT was less or equal compared to renal parenchyma on unenhanced CT (P > 0.05), while tumor enhancement after administration of a contrast agent was lower than that of normal renal parenchyma (P < 0.05). WT was isointense on T1-weighted (T1W) imaging, isointense or hypointense on T2-weighted (T2W) imaging. Tumor enhancement was less than normal renal cortex in all phases (P < 0.05). The number of tumor stages (grades I, II, III, and IV) was two, three, six, and five cases, respectively. Follow-up time was in the range of 19–123 months; six patients died within 3 years, six patients died within 5 years after the initial diagnosis, with the remaining patients still alive.

Conclusion

Adult WT tends to be a large tumor, isointense or hypointense on T2W imaging with enhancement less than normal renal parenchyma in all phases. The long-term follow-up results demonstrated the poor prognosis of the tumor.

Tags: Imaging

Nuclear Medicine and Molecular Imaging

Erratum to: FDG-PET/ceCT is useful to predict recurrence of Pseudomyxoma peritonei

Monday, June 13, 2016, 17:42

Tags: Imaging

Nuclear Medicine and Molecular Imaging

Erratum to: Quantitative assessment of atherosclerotic plaques on 18 F-FDG PET/MRI: comparison with a PET/CT hybrid system

Monday, June 13, 2016, 17:42

Tags: Imaging

Nuclear Medicine and Molecular Imaging

Book Review on: Radioguided Surgery: Current Applications and Innovative Directions in Clinical Practice. Ken Hermann, Omgo E. Neiweg and Stephen P. Povoski (eds). Springer, Heidelberg, Germany

Monday, June 13, 2016, 17:42

Tags: Imaging

Nuclear Medicine and Molecular Imaging

Recurrent prosthetic mitral valve infective endocarditis and perivalvular abscess: first description by PET/CT angiography

Monday, June 13, 2016, 17:42

Tags: Imaging

Nuclear Medicine and Molecular Imaging

Riemer H.J.A.Slart, René A.Tio, Philip H.Elsinga, Markus Schwaiger (Eds): Autonomic Innervation of the Heart: Role of Molecular Imaging

Monday, June 13, 2016, 17:42

Tags: Imaging

Nuclear Medicine and Molecular Imaging

Mirko D'Onofrio, Paola Capelli and Paolo Pederzoli (Eds) Imaging and Pathology of Pancreatic Neoplasms. A Pictorial Atlas

Monday, June 13, 2016, 17:42

Tags: Imaging

Nuclear Medicine and Molecular Imaging

Diffuse bone metastases on 68 Ga-PSMA PET-CT in a patient with prostate cancer and normal bone scan

Monday, June 13, 2016, 17:42

Abstract

A 75-year-old patient was diagnosed with a Gleason 9 prostate carcinoma. His PSA level was 50.4 ng/ml. Routine bone scintigraphy was negative for metastasis (a). Due to the high tumour grading and relatively high PSA level, ⁶⁸Ga-PSMA PET-CT was ordered to rule out distant metastases. This scan showed numerous skeletal lesions with high tracer accumulation as sign of diffuse osseous metastases (b). On low-dose CT there were no signs of sclerosis (c). ⁶⁸Ga-PSMA PET-CT also showed high uptake in the prostate and in para-iliac and para-aortal lymph nodes, without lymph node enlargement. No bone biopsy was obtained to confirm the metastases. Due to this result, the treatment plan was changed to systemic therapy, instead of local therapy.

Tags: Imaging

Nuclear Medicine and Molecular Imaging

FDG PET/CT texture analysis for predicting the outcome of lung cancer treated by stereotactic body radiation therapy

Monday, June 13, 2016, 17:42

Abstract

Introduction

With ¹⁸F-FDG PET/CT, tumor uptake intensity and heterogeneity have been associated with outcome in several cancers. This study aimed at investigating whether ¹⁸F-FDG uptake intensity, volume or heterogeneity could predict the outcome in patients with non-small cell lung cancers (NSCLC) treated by stereotactic body radiation therapy (SBRT).

Methods

Sixty-three patients with NSCLC treated by SBRT underwent a ¹⁸F-FDG PET/CT before treatment. Maximum and mean standard uptake value (SUVmax and SUVmean), metabolic tumoral volume (MTV), total lesion glycolysis (TLG), as well as 13 global, local and regional textural features were analysed. The predictive value of these parameters, along with clinical features, was assessed using univariate and multivariate analysis for overall survival (OS), disease-specific survival (DSS) and disease-free survival (DFS). Cutoff values were obtained using logistic regression analysis, and survivals were compared using Kaplan-Meier analysis.

Results

The median follow-up period was 27.1 months for the entire cohort and 32.1 months for the surviving patients. At the end of the study, 25 patients had local and/or distant recurrence including 12 who died because of the cancer progression. None of the clinical variables was predictive of the outcome, except age, which was associated with DFS (HR 1.1, P = 0.002). None of the ¹⁸F-FDG PET/CT or clinical parameters, except gender, were associated with OS. The univariate analysis showed that only dissimilarity (D) was associated with DSS (HR = 0.822, P = 0.037), and that several metabolic measurements were associated with DFS. In multivariate analysis, only dissimilarity was significantly associated with DSS (HR = 0.822, P = 0.037) and with DFS (HR = 0.834, P < 0.01).

Conclusion

The textural feature dissimilarity measured on the baseline ¹⁸F-FDG PET/CT appears to be a strong independent predictor of the outcome in patients with NSCLC treated by SBRT. This may help selecting patients who may benefit from closer monitoring and therapeutic optimization.

Tags: Imaging

Nuclear Medicine and Molecular Imaging

Molecular imaging using PSMA PET/CT versus multiparametric MRI for initial staging of prostate cancer: comparing apples with oranges?

Monday, June 13, 2016, 17:42

Tags: Imaging

Nuclear Medicine and Molecular Imaging

The reproducibility and prognostic value of serial measurements of heart rate response to regadenoson during myocardial perfusion imaging

Monday, June 13, 2016, 17:42

Abstract

Purpose

The heart rate response (HRR, percentage change from baseline) to regadenoson during myocardial perfusion imaging (MPI) can provide incremental prognostic value in patients with known or suspected coronary artery disease. Our purpose was to evaluate the variability and prognostic value of HRR on serial measurements.

Methods

We studied 648 consecutive patients (61 ± 11 years, 48 % with diabetes) who underwent two regadenoson MPI studies (16 ± 9 months between studies). HRR <30 % was defined as abnormal. All-cause mortality was determined by chart review and verified using the US Social Security Death Master File.

Results

HRR was well correlated between the two studies (intraclass correlation coefficient 0.72, 95 % CI 0.67 – 0.76) with no systematic bias (mean difference 0.88 %, p = 0.2) or proportional bias (p = 0.5) by Bland-Altman analysis in all patients and in those with normal MPI on both studies. Of the 308 patients (48 %) with normal baseline HRR (HRR-1), 33 % had developed a blunted HRR on the second MPI study (HRR-2). Older age, male gender, end-stage renal disease, and abnormal baseline left ventricular ejection fraction were independent predictors of a new-onset abnormal HRR. During a mean follow-up of 2.4 ± 1.2 years, 55 patients (8.5 %) died. Patients with a blunted HRR-1 had increased mortality risk irrespective of their HRR-2 (p = 0.9, log-rank test). Among patients with normal HRR-1, a blunted HRR-2 was an independent predictor of all-cause mortality beyond clinical and traditional MPI data (hazard ratio 2.83, 95 % CI 1.14 – 7.03). Finally, patients with a normal HRR-1 and HRR-2 had the lowest event rate, while those with any abnormal HRR had an increased risk of death (hazard ratio 2.5, 95 % CI 1.2 – 5.4).

Conclusion

There was good correlation in the HRR to regadenoson on serial measurements without systematic or proportional biases. Patients with consistently normal HRR had the best prognosis.

Tags: Imaging

Mediators of Inflammation

C-Terminal Alpha-1 Antitrypsin Peptide: A New Sepsis Biomarker with Immunomodulatory Function

Nancy Blaurock, Diana Schmerler, Kerstin Hünniger, Oliver Kurzai, Katrin Ludewig, Michael Baier, Frank Martin Brunkhorst, Diana Imhof, And Michael Kiehntopf · Monday, June 13, 2016, 16:12

Systemic inflammatory response syndrome (SIRS) is a life threatening condition and the leading cause of death in intensive care units. Although single aspects of pathophysiology have been described in detail, numerous unknown mediators contribute to the progression of this complex disease. The aim of this study was to elucidate the pathophysiological role of CAAP48, a C-terminal alpha-1 antitrypsin fragment, that we found to be elevated in septic patients and to apply this peptide as diagnostic marker for infectious and noninfectious etiologies of SIRS. Incubation of human polymorphonuclear neutrophils with synthetic CAAP48, the SNP-variant CAAP47, and several control peptides revealed intense neutrophil activation, induction of neutrophil chemotaxis, reduction of neutrophil viability, and release of cytokines. We determined the abundance of CAAP48 in patients with severe sepsis, severe SIRS of noninfectious origin, and viral infection. CAAP48 levels were 3-4-fold higher in patients with sepsis compared to SIRS of noninfectious origin and allowed discrimination of those patients with high sensitivity and specificity. Our results suggest that CAAP48 is a promising discriminatory sepsis biomarker with immunomodulatory functions, particularly on human neutrophils, supporting its important role in the host response and pathophysiology of sepsis.

Tags: Imaging

Academic Radiology

Evaluation of Radiology Teachers' Performance and Identification of the "Best Teachers" in a Residency Program

Monday, June 13, 2016, 14:02

Publication date: July 2016
Source:Academic Radiology, Volume 23, Issue 7
Author(s): Álvaro Huete, Rodrigo Julio, Viviana Rojas, Cristián Herrera, Oslando Padilla, Nancy Solís, Margarita Pizarro, Lorena Etcheberry, Alberto Sarfatis, Gonzalo Pérez, Luis A. Díaz, Alejandro Delfino, Estrella Muñoz, Horacio Rivera, Dimitri A. Parra, Marcela Bitran, Arnoldo Riquelme
Rationale and Objectives Radiology teachers are well trained in their specialty; however, when working in academic institutions, faculty development and promotion through the education pathway tends to be based on their teaching knowledge and skills. The aim of this study is to assess psychometric properties of the Medicina Universidad Católica—Radiology 32 items (MEDUC-RX32), an instrument designed to evaluate the performance of postgraduate radiology teachers and to identify the best teachers. Materials and Methods Mixed methodology was used, including qualitative and quantitative phases. The psychometric properties of the MEDUC-RX32 survey were performed by factor analysis (validity), Cronbach alpha coefficient, and G coefficient (reliability). The residents assessed their teachers and simultaneously voted for the "best teacher," which was used as a gold standard for the receiver operating characteristic curves construction comparing their votes with the global score. Results A total of 28 residents answered 164 surveys. The global score was 6.23 ± 0.8 (scale from 1 to 7). The factor analysis showed six domains of the resident's perception: (1) tutorial teaching, feedback, and independent learning; (2) communication and teamwork; (3) learning objectives; (4) respectful behavior; (5) radiological report; and (6) teaching and care support. The tutor's strengths were related with respectful behavior and teamwork. The instrument is highly reliable with a Cronbach alpha of 0.937 and a G coefficient of 0.831 (with a minimum of 8 residents). The MEDUC-RX32 instrument has a sensitivity of 91.7% and specificity of 83.3% to identify tutors as best teachers with at least one vote with an area under the receiver operating characteristic curve of 0.931 with a cutoff of 5.94. Conclusions The MEDC-RX32 instrument is a multidimensional, valid, and highly reliable method to evaluate radiology teachers, identifying teachers with excellence in tutorial teaching in a postgraduate radiology program. 

Tags: Imaging

Academic Radiology

Musculoskeletal Ultrasound Training for Radiology Residents

Monday, June 13, 2016, 14:02

Publication date: July 2016
Source:Academic Radiology, Volume 23, Issue 7
Author(s): Ezekiel Maloney, Daniel S. Hippe, Angelisa Paladin, Felix S. Chew, Alice S. Ha
Rationale and Objectives A prospective randomized study was conducted to assess whether an electronic learning module was as effective as a didactic lecture to teach musculoskeletal ultrasound to radiology residents. Materials and Methods Thirty-three residents were randomized into a module group versus a didactic group. All residents took a written "pretest" to assess baseline knowledge. Subsequently, the 17 residents in the didactic group attended a live didactic session delivered by a subspecialist musculoskeletal radiology faculty member. The 16 residents in the module group completed an electronic learning module that contained similar content to the live didactic session. Finally, all residents completed a written "posttest," which served as the outcome measure. Results Mean score significantly improved between pre- and posttest by 10.6 ± 11.2% in the didactic group (DG; P = 0.002) and 14.0 ± 8.2% in the module group (MG; P < 0.001), with a nonsignificant difference between groups (P = 0.4). Mean pretest scores (75.6 ± 9.4% DG and 73.7 ± 9.2% MG, P = 0.6) and posttest scores (86.2 ± 9.7% DG and 87.7 ± 5.2% MG, P = 0.5) were not significantly different. The adjusted mean difference in posttest scores between groups was −1.9% (95% confidence interval: −7.2 to 3.5%). Conclusion If didactic training was better than electonic module training, the difference was relatively small (<5%). A similar web-based, interactive module could be employed to teach American Board of Radiology Core Examination and Accreditation Council for Graduate Medical Education (ACGME) Diagnostic Radiology Milestone musculoskeletal ultrasound learning objectives to radiology residents. An electronic module could reduce demands on faculty staff time invested in musculoskeletal ultrasound training and be more widely available to residents. 

Tags: Imaging

Academic Radiology

Teaching Principles of Patient-Centered Care During Radiology Residency

Monday, June 13, 2016, 14:02

Publication date: July 2016
Source:Academic Radiology, Volume 23, Issue 7
Author(s): Matthew M. Miller, Priscilla J. Slanetz, Ana P. Lourenco, Ronald L. Eisenberg, Justin W. Kung
Rationale and Objectives Patient-centered healthcare delivery has become increasingly established as a cornerstone of quality medical care, but teaching these principles in a radiology residency setting is often difficult and ineffective in a traditional lecture format. We developed a novel educational session in which actual patient letters about a healthcare provider are used to facilitate a case-based discussion of key principles of patient-centered care. Materials and Methods A novel patient letter-facilitated, case-based session was conducted at two different university-based teaching institutions. Prior to the educational session, patient letters introducing the principles of patient-centered care were distributed to residents for review. During the session, radiology-specific cases were discussed in the context of the principles introduced by the letters. A post-session survey was administered to evaluate the efficacy and usefulness of the session. Results Forty-six of the 61 session attendees (75%) completed the post session survey. Most respondents (93%) preferred this case-based, interactive session to a typical didactic session. A majority of the residents indicated that both the patient letters (64%) and radiology specific cases (73%) helped them think differently about how they interact with patients. They indicated that the session enhanced their understanding of professionalism (3.7 out of 5.0 [95% CI 3.4–4.0]) and increased their motivation to become more patient-centered (3.0 out of 4.0 [95% CI 2.8–3.3]). Conclusions Our findings suggest that patient letter-facilitated, case-based sessions may influence resident attitudes regarding the principles of patient-centered care and may help to increase resident motivation to become more patient-centered in their own practice. 

Tags: Imaging

Academic Radiology

Flipping Radiology Education Right Side Up

Monday, June 13, 2016, 14:02

Publication date: July 2016
Source:Academic Radiology, Volume 23, Issue 7
Author(s): Erin E. O'Connor, Jessica Fried, Nancy McNulty, Pallav Shah, Jeffery P. Hogg, Petra Lewis, Thomas Zeffiro, Vikas Agarwal, Sravanthi Reddy
Rationale and Objectives In flipped learning, medical students independently learn facts and concepts outside the classroom, and then participate in interactive classes to learn to apply these facts. Although there are recent calls for medical education reform using flipped learning, little has been published on its effectiveness. Our study compares the effects of flipped learning to traditional didactic instruction on students' academic achievement, task value, and achievement emotions. Materials and Methods At three institutions, we alternated flipped learning with traditional didactic lectures during radiology clerkships, with 175 medical students completing a pretest on general diagnostic imaging knowledge to assess baseline cohort comparability. Following instruction, posttests and survey examinations of task value and achievement emotions were administered. Linear mixed effects analysis was used to examine the relationship between test scores and instruction type. Survey responses were modeled using ordinal category logistic regression. Instructor surveys were also collected. Results There were no baseline differences in test scores. Mean posttest minus pretest scores were 10.5% higher in the flipped learning group than in the didactic instruction group (P = 0.013). Assessment of task value and achievement emotions showed greater task value, increased enjoyment, and decreased boredom with flipped learning (all P < 0.01). All instructors preferred the flipped learning condition. Conclusions Flipped learning was associated with increased academic achievement, greater task value, and more positive achievement emotions when compared to traditional didactic instruction. Further investigation of flipped learning methods in radiology education is needed to determine whether flipped learning improves long-term retention of knowledge, academic success, and patient care. 

Tags: Imaging

Academic Radiology

Instructional Vignettes in Publication and Journalism Ethics in Radiology Research

Monday, June 13, 2016, 14:02

Publication date: July 2016
Source:Academic Radiology, Volume 23, Issue 7
Author(s): Andrew B. Rosenkrantz, Luke A. Ginocchio
Rationale and Objectives The aim of the present study was to assess the potential usefulness of written instructional vignettes relating to publication and journalism ethics in radiology via a survey of radiology trainees. Materials and Methods A literature review was conducted to guide the development of vignettes, each describing a scenario relating to an ethical issue in research and publication, with subsequent commentary on the underlying ethical issue and potential approaches to its handling. Radiology trainees at a single institution were surveyed regarding the vignettes' perceived usefulness. Results A total of 21 vignettes were prepared, addressing institutional review board and human subjects protection, authorship issues, usage of previous work, manuscript review, and other miscellaneous topics. Of the solicited trainees, 24.7% (16/65) completed the survey. On average among the vignettes, 94.0% of the participants found the vignette helpful; 19.9 received prior formal instruction on the issue during medical training; 40.0% received prior informal guidance from a research mentor; and 42.0% indicated that the issue had arisen in their own or a peer's prior research experience. The most common previously experienced specific issue was authorship order (93.8%). Free-text responses were largely favorable regarding the value of the vignettes, although also indicated numerous challenges in properly handling the ethical issues: impact of hierarchy, pressure to publish, internal politics, reluctance to conduct sensitive conversations with colleagues, and variability in journal and professional society policies. Conclusion Radiology trainees overall found the vignettes helpful, addressing commonly encountered topics for which formal and informal guidance were otherwise lacking. The vignettes are publicly available through the Association of University Radiologists (AUR) website and may foster greater insights by investigators into ethical aspects of the publication and journalism process, thus contributing to higher quality radiology research. 

Tags: Imaging

Academic Radiology

Incorporation of Ultrasound Education Into Medical School Curricula

Monday, June 13, 2016, 14:02

Publication date: July 2016
Source:Academic Radiology, Volume 23, Issue 7
Author(s): Andrew Phelps, Jennifer Wan, Christopher Straus, David M. Naeger, Emily M. Webb
Rationale and Objectives This study aimed to determine the degree of involvement of radiologists in ultrasound education in medical schools in the United States. Materials and Methods An online survey was sent to 129 directors of medical student education in radiology, identified by the Alliance of Medical Student Educators in Radiology. Each survey recipient represented a unique medical school. Results There was a 31% survey completion rate. Radiology education was incorporated into the majority of respondents' medical school curricula (95%). Ultrasound images were used in preclinical education in the majority of schools (76%). Students were trained to perform hands-on ultrasound examinations in half of schools (49%), and a minority of schools offered a dedicated point-of-care ultrasound elective (14%). Radiology and emergency medicine were the most involved departments in teaching ultrasound to medical students (88% and 75% of medical schools, respectively). Conclusions Ultrasound imaging was incorporated into the curricula of most of the responding medical schools, although actual hands-on training was less widespread. 

Tags: Imaging

Academic Radiology

Brain Friendly Teaching—Reducing Learner's Cognitive Load

Monday, June 13, 2016, 14:02

Publication date: July 2016
Source:Academic Radiology, Volume 23, Issue 7
Author(s): Petra J. Lewis
Many didactic lectures induce a cognitive load in learners out of proportion to the content that they need to learn (or can learn) during that teaching session. This is due in part to the content, and in part to the way it is displayed or presented. By reducing the cognitive load on our audience, we can increase long-term retention of information. This article briefly summarizes some of the science behind cognitive load as it relates to presentations, and identifies simple steps to reduce it, while maximizing learning. 

Tags: Imaging

Academic Radiology

Teaching the Healthcare Economics Milestones to Radiology Residents

Monday, June 13, 2016, 14:02

Publication date: July 2016
Source:Academic Radiology, Volume 23, Issue 7
Author(s): Allen S. Prober, William A. Mehan, Harprit S. Bedi
Rationale and Objectives Since July 2013, the Accreditation Council for Graduate Medical Education (ACGME) has required radiology residency programs to implement a set of educational milestones to track residents' educational advancement in six core competencies, including Systems-based Practice. The healthcare economics subcompetency of Systems-based Practice has traditionally been relatively neglected, and given the new increased ACGME oversight, will specifically require greater focused attention. Materials and Methods A multi-institutional health-care economics pilot curriculum combining didactic and practical components was implemented across five residency programs. The didactic portion included a package of online recorded presentations, reading, and testing materials developed by the American College of Radiology (ACR's) Radiology Leadership Institute. The practical component involved a series of local meetings led by program faculty with the production of a deliverable based on research of local reimbursement for a noncontrast head computed tomography. The capstone entailed the presentation of each program's deliverable during a live teleconference webcast with a Radiology Leadership Institute content expert acting as moderator and discussion leader. Results The pilot curriculum was well received by residents and faculty moderators, with 100% of survey respondents agreeing that the pilot met its objective of introducing how reimbursement works in American radiology in 2015 and how business terminology applies to their particular institutions. Conclusion A health-care economics curriculum in the style of a Massive Open Online Course has strong potential to serve as many residency programs' method of choice in meeting the health-care economics milestones. 

Tags: Imaging

Academic Radiology

Radiologic-pathologic Correlation—An Advanced Fourth-year Elective

Monday, June 13, 2016, 14:02

Publication date: July 2016
Source:Academic Radiology, Volume 23, Issue 7
Author(s): Matthew Hartman, Jan Silverman, Laura Spruill, Jeanne Hill
Traditionally, the radiology elective has been designed to teach medical students the fundamentals of radiologic interpretation. When questioned, many students state that they want to take a radiology elective so they can "interpret images." For the students on radiology, rotation/elective education was often passive, consisting of didactic conferences and observational shadowing of radiologists as they interpreted images. Students had only a superficial appreciation of how radiologists interacted with clinical services, multidisciplinary teams, and pathology. There was very little emphasis on imaging appropriateness or the most efficient and effective imaging for various clinical problems. With the expansion of numerous imaging modalities and the emphasis on patient-centered care, including imaging safety and dose reduction, it is important to change the focus of radiology education from interpretation to the optimal integration of imaging into clinical medicine. Radiology-pathology (rad path) electives were created at Allegheny General Hospital and the Medical University of South Carolina as a new option to provide a high-quality advanced elective for fourth-year medical students. These electives enable students to correlate radiologic images with gross and microscopic pathology specimens, thus increasing their knowledge and understanding of both. The rad path elective combines aspects of surgery, radiology, and pathology and requires students to be active learners. The implementation of this elective is an exciting work in progress that has been evolving over the past 2 and 4 years at Medical University of South Carolina and Allegheny General Hospital, respectively. We will discuss the historical basis for the elective, the advantages and challenges of having such an integrated course, and some different strategies for creating a rad path elective. 

Tags: Imaging

Academic Radiology

Designing Radiology Outcomes Studies—Essential Principles

Monday, June 13, 2016, 14:02

Publication date: July 2016
Source:Academic Radiology, Volume 23, Issue 7
Author(s): Stella K. Kang, Alvin I. Mushlin
Health outcomes research is essential to align radiology with current standards of high-value patient care, through the assessment of end results of diagnostic tests, interventions, or policy on patient health. To bridge studies of diagnostic test accuracy and health outcomes research, key considerations include: (1) how to determine when a diagnostic test merits evaluation of impact on outcomes, (2) when study of intermediate/surrogate outcomes can be useful, (3) how to consider the possible harms as well as potential benefits of a test, and (4) how to integrate evidence of an imaging test's efficacy/effectiveness with clinical data to assess outcomes. Due to challenges in conducting studies of long-term outcomes consequent to imaging use, intermediate health outcomes may capture a test's impact on successful diagnosis and therapy, and can provide readily measurable, incremental insights into the role of imaging in health-care delivery and efficiency. In an era marked by recognition of quality and value of care, outcomes research will provide essential evidence to inform radiologists' guidance of imaging use toward improved patient care, creation of clinical guidelines, and policy decisions. 

Tags: Imaging

Academic Radiology

Simulation in Radiology Education

Monday, June 13, 2016, 14:02

Publication date: July 2016
Source:Academic Radiology, Volume 23, Issue 7
Author(s): Katherine A. Klein, Colleen H. Neal
Objective The purpose of this article is to discuss the use of simulation in radiology education. Conclusion Simulation is an engaging way to educate radiology trainees. It allows trainees to improve their procedural and clinical skills in a calm, supportive environment that optimizes patient safety. Familiarity with the principles of simulation education may help radiologists evaluate their training curricula to identify skills that could be augmented with simulation training. 

Tags: Imaging

Academic Radiology

Automation of Educational Tasks for Academic Radiology

Monday, June 13, 2016, 14:02

Publication date: July 2016
Source:Academic Radiology, Volume 23, Issue 7
Author(s): David L. Lamar, Michael L. Richardson, Blake Carlson
Rationale and Objectives The process of education involves a variety of repetitious tasks. We believe that appropriate computer tools can automate many of these chores, and allow both educators and their students to devote a lot more of their time to actual teaching and learning. This paper details tools that we have used to automate a broad range of academic radiology-specific tasks on Mac OS X, iOS, and Windows platforms. Some of the tools we describe here require little expertise or time to use; others require some basic knowledge of computer programming. Materials and Methods We used TextExpander (Mac, iOS) and AutoHotKey (Win) for automated generation of text files, such as resident performance reviews and radiology interpretations. Custom statistical calculations were performed using TextExpander and the Python programming language. A workflow for automated note-taking was developed using Evernote (Mac, iOS, Win) and Hazel (Mac). Automated resident procedure logging was accomplished using Editorial (iOS) and Python. We created three variants of a teaching session logger using Drafts (iOS) and Pythonista (iOS). Editorial and Drafts were used to create flashcards for knowledge review. We developed a mobile reference management system for iOS using Editorial. We used the Workflow app (iOS) to automatically generate a text message reminder for daily conferences. Finally, we developed two separate automated workflows—one with Evernote (Mac, iOS, Win) and one with Python (Mac, Win)—that generate simple automated teaching file collections. Results We have beta-tested these workflows, techniques, and scripts on several of our fellow radiologists. All of them expressed enthusiasm for these tools and were able to use one or more of them to automate their own educational activities. Conclusions Appropriate computer tools can automate many educational tasks, and thereby allow both educators and their students to devote a lot more of their time to actual teaching and learning. 

Tags: Imaging

Mediators of Inflammation

Semisynthesis of Derivatives of Oleanolic Acid from Syzygium aromaticum and Their Antinociceptive and Anti-Inflammatory Properties

Sibusiso Rali, Opeoluwa O. Oyedeji, Olukayode O. Aremu, Adebola O. Oyedeji, And Benedicta N. Nkeh-chungag · Monday, June 13, 2016, 12:11

Oleanolic acid is a pentacyclic triterpenoid compound widely found in plants and well known for its medicinal properties. Oleanolic acid (OA) was isolated from the ethyl acetate extract of Syzygium aromaticum flower buds. Semisynthesis afforded both acetate and ester derivatives. The derived compounds were monitored with thin layer chromatography and confirmed with nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry (MS), Fourier infrared (FT-IR) spectroscopy, and melting point (Mp). All these compounds were evaluated for their analgesic and anti-inflammatory properties at a dose of 40 mg/kg. Significant analgesic and anti-inflammatory effects were noted for all OA-derived compounds. In the formalin-induced pain test, the derivatives showed better analgesic effects compared to their precursor, whereas, in the tale flick test, oleanolic acid proved to be superior in analgesic effects compared to all its derivatives with the exception of the acetyl derivative. Acute inflammatory tests showed that acetyl derivatives possessed better anti-inflammatory activity compared to the other compounds. In conclusion, semisynthesis of oleanolic acid yielded several derivatives with improved solubility and enhanced analgesic and anti-inflammatory properties.

Tags: Imaging

Mediators of Inflammation

MicroRNA-Regulated Proinflammatory Cytokines in Sarcopenia

Jingjing Fan, Xianjuan Kou, Yi Yang, And Ning Chen · Monday, June 13, 2016, 12:11

Sarcopenia has been defined as the aging-related disease with the declined mass, strength, and function of skeletal muscle, which is the major cause of frailty and falls in elders. The activation of inflammatory signal pathways due to diseases and aging is suggested to reveal the critical impact on sarcopenia. Several proinflammatory cytokines, especially interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), play crucial roles in modulation of inflammatory signaling pathway during the aging-related loss of skeletal muscle. MicroRNAs (miRNAs) have emerged as the important regulators for the mass and functional maintenance of skeletal muscle through regulating gene expression of proinflammatory cytokines. In this paper, we have systematically discussed regulatory mechanisms of miRNAs for the expression and secretion of inflammatory cytokines during sarcopenia, which will provide some novel targets and therapeutic strategies for controlling aging-related atrophy of skeletal muscle and corresponding chronic inflammatory diseases.

Tags: Imaging

Mediators of Inflammation

Epithelial Anion Transport as Modulator of Chemokine Signaling

Andrea Schnúr, Péter Hegyi, Simon Rousseau, Gergely L. Lukacs, And Guido Veit ·Sunday, June 12, 2016, 12:11

The pivotal role of epithelial cells is to secrete and absorb ions and water in order to allow the formation of a luminal fluid compartment that is fundamental for the epithelial function as a barrier against environmental factors. Importantly, epithelial cells also take part in the innate immune system. As a first line of defense they detect pathogens and react by secreting and responding to chemokines and cytokines, thus aggravating immune responses or resolving inflammatory states. Loss of epithelial anion transport is well documented in a variety of diseases including cystic fibrosis, chronic obstructive pulmonary disease, asthma, pancreatitis, and cholestatic liver disease. Here we review the effect of aberrant anion secretion with focus on the release of inflammatory mediators by epithelial cells and discuss putative mechanisms linking these transport defects to the augmented epithelial release of chemokines and cytokines. These mechanisms may contribute to the excessive and persistent inflammation in many respiratory and gastrointestinal diseases.

Tags: Imaging

Mediators of Inflammation

Pretransplant Immune- and Apoptosis-Related Gene Expression Is Associated with Kidney Allograft Function

Dorota Kamińska, Katarzyna Kościelska-kasprzak, Paweł Chudoba, Oktawia Mazanowska, Mirosław Banasik, Marcelina Żabinska, Maria Boratyńska, Agnieszka Lepiesza, Agnieszka Gomółkiewicz, Piotr Dzięgiel, And Marian Klinger · Sunday, June 12, 2016, 12:11

Renal transplant candidates present immune dysregulation, caused by chronic uremia. The aim of the study was to investigate whether pretransplant peripheral blood gene expression of immune factors affects clinical outcome of renal allograft recipients. Methods. In a prospective study, we analyzed pretransplant peripheral blood gene expression in87 renal transplant candidates with real-time PCR on custom-designed low density arrays (TaqMan). Results. Immediate posttransplant graft function (14-day GFR) was influenced negatively by TGFB1 () and positively by IL-2 gene expression (). Pretransplant blood mRNA expression of apoptosis-related genes (CASP3, FAS, and IL-18) and Th1-derived cytokine gene IFNG correlated positively with short- (6-month GFR CASP3: , FAS: , and IFNG: ) and long-term graft function (24-month GFR CASP3: , FAS: , IL-18: , and IFNG: ). Conclusion. Lowered pretransplant Th1-derived cytokine and apoptosis-related gene expressions were a hallmark of subsequent worse kidney function but not of acute rejection rate. The pretransplant IFNG and CASP3 and FAS and IL-18 genes' expression in the recipients' peripheral blood is the possible candidate for novel biomarker of short- and long-term allograft function.

Tags: Imaging

Medical Image Analysis

Characterization of Myocardial Motion Patterns by Unsupervised Multiple Kernel Learning

Sunday, June 12, 2016, 7:09

Publication date: Available online 11 June 2016
Source:Medical Image Analysis
Author(s): Sergio Sanchez-Martinez, Nicolas Duchateau, Tamas Erdei, Alan G. Fraser, Bart H. Bijnens, Gemma Piella
We propose an independent objective method to characterize different patterns of functional responses to stress in the heart failure with preserved ejection fraction (HFPEF) syndrome by combining multiple temporally-aligned myocardial velocity traces at rest and during exercise, together with temporal information on the occurrence of cardiac events (valves openings/closures and atrial activation). The method builds upon multiple kernel learning, a machine learning technique that allows the combination of data of different nature and the reduction of their dimensionality towards a meaningful representation (output space). The learning process is kept unsupervised, to study the variability of the input traces without being conditioned by data labels. To enhance the physiological interpretation of the output space, the variability that it encodes is analyzed in the space of input signals after reconstructing the velocity traces via multiscale kernel regression. The methodology was applied to 2D sequences from a stress echocardiography protocol from 55 subjects (22 healthy, 19 HFPEF and 14 breathless subjects). The results confirm that characterization of the myocardial functional response to stress in the HFPEF syndrome may be improved by the joint analysis of multiple relevant features. 

Graphical abstract

Tags: BioEngineering, Imaging

Medical Image Analysis

Computing Group Cardinality Constraint Solutions for Logistic Regression Problems

Sunday, June 12, 2016, 7:09

Publication date: Available online 11 June 2016
Source:Medical Image Analysis
Author(s): Yong Zhang, Dongjin Kwon, Kilian M. Pohl
We derive an algorithm to directly solve logistic regression based on cardinality constraint, group sparsity and use it to classify intra-subject MRI sequences (e.g. cine MRIs) of healthy from diseased subjects. Group cardinality constraint models are often applied to medical images in order to avoid overfitting of the classifier to the training data. Solutions within these models are generally determined by relaxing the cardinality constraint to a weighted feature selection scheme. However, these solutions relate to the original sparse problem only under specific assumptions, which generally do not hold for medical image applications. In addition, inferring clinical meaning from features weighted by a classifier is an ongoing topic of discussion. Avoiding weighing features, we propose to directly solve the group cardinality constraint logistic regression problem by generalizing the Penalty Decomposition method. To do so, we assume that an intra-subject series of images represents repeated samples of the same disease patterns. We model this assumption by combining series of measurements created by a feature across time into a single group. Our algorithm then derives a solution within that model by decoupling the minimization of the logistic regression function from enforcing the group sparsity constraint. The minimum to the smooth and convex logistic regression problem is determined via gradient descent while we derive a closed form solution for finding a sparse approximation of that minimum. We apply our method to cine MRI of 38 healthy controls and 44 adult patients that received reconstructive surgery of Tetralogy of Fallot (TOF) during infancy. Our method correctly identifies regions impacted by TOF and generally obtains statistically significant higher classification accuracy than alternative solutions to this model, i.e., ones relaxing group cardinality constraints. 

Graphical abstract

Tags: BioEngineering, Imaging

Medical Image Analysis

A Graph Theoretic Approach for Computing 3D+time Biventricular Cardiac Strain from Tagged MRI Data

Sunday, June 12, 2016, 7:09

Publication date: Available online 11 June 2016
Source:Medical Image Analysis
Author(s): Ming Li, Himanshu Gupta, Steven G. Lloyd, Louis J. Dell'Italia, Thomas S. Denney Jr.
Tagged magnetic resonance imaging (tMRI) is a well-established method for evaluating regional mechanical function of the heart. Many techniques have been developed to compute 2D or 3D cardiac deformation and strain from tMRI images. In this paper, we present a new method for measuring 3D plus time biventricular myocardial strain from tMRI data. The method is composed of two parts. First, we use a Gabor filter bank to extract tag points along tag lines. Second, each tag point is classified to one of a set of indexed reference tag lines using a point classification with graph cuts (PCGC) algorithm and a motion compensation technique. 3D biventricular deformation and strain is computed at each image time frame from the classified tag points using a previously published finite difference method. The strain computation is fully automatic after myocardial contours are defined near end-diastole and end-systole. An in-vivo dataset composed of 30 human imaging studies with a range of pathologies was used for validation. Strains computed with the PCGC method with no manual corrections were compared to strains computed from both manually placed tag points and a manually-corrected unwrapped phase method. A typical cardiac imaging study with 10 short-axis slices and 6 long-axis slices required 30 minutes for contouring followed by 44 minutes of automated processing. The results demonstrate that the proposed method can reconstruct accurate 3D plus time cardiac strain maps with minimal user intervention. 

Graphical abstract

Tags: BioEngineering, Imaging

Ultrasound in Medicine & Biology

Quantification of Endothelial αvβ3 Expression with High-Frequency Ultrasound and Targeted Microbubbles: In Vitro and In Vivo Studies

Sunday, June 12, 2016, 3:41

Publication date: Available online 11 June 2016
Source:Ultrasound in Medicine & Biology
Author(s): Verya Daeichin, Klazina Kooiman, Ilya Skachkov, Johan G. Bosch, Thomas L. Theelen, Katja Steiger, Andrew Needles, Ben J. Janssen, Mat J.A.P. Daemen, Antonius F.W. van der Steen, Nico de Jong, Judith C. Sluimer
Angiogenesis is a critical feature of plaque development in atherosclerosis and might play a key role in both the initiation and later rupture of plaques. The precursory molecular or cellular pro-angiogenic events that initiate plaque growth and that ultimately contribute to plaque instability, however, cannot be detected directly with any current diagnostic modality. This study was designed to investigate the feasibility of ultrasound molecular imaging of endothelial αvβ3 expression in vitro and in vivo using αvβ3-targeted ultrasound contrast agents (UCAs). In the in vitro study, αvβ3 expression was confirmed by immunofluorescence in a murine endothelial cell line and detected using the targeted UCA and ultrasound imaging at 18-MHz transmit frequency. In the in vivo study, expression of endothelial αvβ3 integrin in murine carotid artery vessels and microvessels of the salivary gland was quantified using targeted UCA and high-frequency ultrasound in seven animals. Our results indicated that endothelial αvβ3 expression was significantly higher in the carotid arterial wall containing atherosclerotic lesions than in arterial segments without any lesions. We also found that the salivary gland can be used as an internal positive control for successful binding of targeted UCA to αvβ3 integrin. In conclusion, αvβ3-targeted UCA allows non-invasive assessment of the expression levels of αvβ3 on the vascular endothelium and may provide potential insights into early atherosclerotic plaque detection and treatment monitoring. 

Tags: Imaging

Academic Radiology

Assessment of Heterogeneity Difference Between Edge and Core by Using Texture Analysis

Saturday, June 11, 2016, 13:59

Publication date: Available online 11 June 2016
Source:Academic Radiology
Author(s): Shiteng Suo, Jiejun Cheng, Mengqiu Cao, Qing Lu, Yan Yin, Jianrong Xu, Huawei Wu
Rationale and Objectives This study aimed to test the hypothesis that the heterogeneity difference between edge and core of lesions by using intensity and entropy features obtained from whole-lesion texture analysis on contrast-enhanced computed tomography (CT) may be useful for differentiation of malignant from inflammatory pulmonary nodules and masses. Materials and Methods In all, 48 single pulmonary nodules and masses were retrospectively evaluated. All lesions were histologically or clinically confirmed (malignancy: inflammation = 24:20). We utilized a newly introduced texture analysis method based on contrast-enhanced CT (first described by Grove et al.) that automatically divided the whole lesion volume into two regions: edge and core. Mean attenuation value (AV) and entropy of each region and also the whole lesion were evaluated separately. Each texture metric (absolute value for each region, and difference value defined as difference between edge and core) of malignant and inflammatory lesions were compared using Mann-Whitney U test. Individual image parameters were combined by using linear discriminant analysis. Receiver operating characteristic curves were generated to assess each texture metric and their combination for discriminating between the two entities. Results Mean AV difference and entropy difference were significantly higher in malignant lesions than in inflammatory lesions (4.71 HU ± 5.06 vs −1.53 HU ± 5.05, P < .001; 0.45 ± 0.23 vs 0.18 ± 0.30, P = .001). Receiver operating characteristic curves for individual mean AV difference and entropy difference provided relatively high values for the area under the curve (0.836 and 0.795, respectively). The combination of mean AV difference, entropy difference, and lesion volume improved the area under the curve to 0.864. Conclusion Heterogeneity difference between edge and core by using whole-lesion texture analysis on contrast-enhanced CT may be a promising tool for estimating the probability of malignancy in pulmonary nodules and masses. 

Tags: Imaging

Academic Radiology

Pulmonary Hypertension and the Quantification of Lung Density on Chest CT

Saturday, June 11, 2016, 13:59

Publication date: Available online 11 June 2016
Source:Academic Radiology
Author(s): Robert H. Brown

Tags: Imaging

Pediatric Radiology

Utility of sedation for young children undergoing dimercaptosuccinic acid renal scans

Saturday, June 11, 2016, 8:59

Abstract

Background

No studies have examined whether use of sedation during a Tc-99 m dimercaptosuccinic acid (DMSA) renal scan reduces patient discomfort.

Objective

To compare discomfort level during a DMSA scan to the discomfort level during other frequently performed uroradiologic tests, and to determine whether use of sedation during a DMSA scan modifies the level of discomfort.

Materials and methods

We examined the discomfort level in 798 children enrolled in the Randomized Intervention for children with Vesicoureteral Reflux (RIVUR) and Careful Urinary Tract Infection Evaluation (CUTIE) studies by asking parents to rate their child's discomfort level with each procedure on a scale from 0 to 10. We compared discomfort during the DMSA scan and the DMSA image quality between centers in which sedation was used >90% of the time (sedation centers), centers in which sedation was used <10% of the time (non-sedation centers), and centers in which sedation was used on a case-by-case basis (selective centers).

Results

Mean discomfort level was highest for voiding cystourethrogram (6.4), followed by DMSA (4.0), followed by ultrasound (2.4; P<0.0001). Mean discomfort level during the DMSA scan was significantly higher at non-sedation centers than at selective centers (P<0.001). No difference was apparent in discomfort level during the DMSA scan between sedation centers and selective centers (P=0.12), or between the sedation centers and non-sedation centers (P=0.80). There were no differences in the proportion with uninterpretable DMSA scans according to sedation use.

Conclusion

Selective use of sedation in children 12–36 months of age can reduce the discomfort level experienced during a DMSA scan.

Tags: Imaging

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