Evaluation of the T2-weighted (T2W) adrenal MRI calculator to differentiate adrenal pheochromocytoma from lipid-poor adrenal adenoma.

OBJECTIVES: To evaluate the T2-weighted (T2W) MRI calculator to differentiate adrenal pheochromocytoma from lipid-poor adrenal adenoma. METHODS: Twenty-nine consecutive pheochromocytomas resected between 2010 and 2019 were compared to 23 consecutive lipid-poor adrenal adenomas. Three blinded radiologists (R1, R2, R3) subjectively evaluated T2W signal intensity and heterogeneity and extracted T2W signal intensity ratio (SIR) and entropy. These values were imputed into a quantitative and qualitative T2W adrenal MRI calculator (logistic regression model encompassing T2W SIR + entropy and subjective SI [relative to renal cortex] and heterogeneity) using a predefined threshold to differentiate metastases from adenoma and accuracy derived by a 2 × 2 table analysis. RESULTS: Subjectively, pheochromocytomas were brighter (p < 0.001) and more heterogeneous (p < 0.001) for all three radiologists. Inter-observer agreement was fair-to-moderate for T2W signal intensity (K = 0.37-0.46) and fair for heterogeneity (K = 0.24-0.32). Pheochromocytoma had higher T2W-SI-ratio (p < 0.001) and entropy (p < 0.001) for all three readers. The quantitative calculator differentiated pheochromocytoma from adenoma with high sensitivity, specificity, and accuracy (100% [95% confidence intervals 88-100%], 87% [66-97%], and 94% [86-100%] R1; 93% [77-99%], 96% [78-100%], and 94% [88-100%] R2; 97% [82-100%], 96% [78-100%], and 96% [91-100% R3]). The qualitative calculator was specific with lower sensitivity and overall accuracy (48% [29-68%], 100% [85-100%], and 74% [65-83%] R1; 45% [26-64%], 100% [85-100%], and 72% [63-82%] R2; 59% [39-77%], 100% [85-100%], and 79% [70-88% R3]). CONCLUSIONS: T2W signal intensity and heterogeneity differ, subjectively and quantitatively, in pheochromocytoma compared to adenoma. Use of a quantitative T2W adrenal calculator which combines T2W signal intensity ratio and entropy was highly accurate to diagnose pheochromocytoma outperforming subjective analysis. KEY POINTS: • Pheochromocytomas have higher T2-weighted signal intensity and are more heterogeneous compared to lipid-poor adrenal adenomas evaluated subjectively and quantitatively. • The quantitative T2-weighted adrenal MRI calculator, a logistic regression model combining T2-weighted signal intensity ratio and entropy, is highly accurate for diagnosis of pheochromocytoma. • The qualitative T2-weighed adrenal MRI calculator had high specificity but lower sensitivity and overall accuracy compared to quantitative assessment and agreement was only fair-to-moderate.

Radiologist Productivity Analytics: Factors Impacting Abdominal Pelvic CT Exam Reporting Times.

The purpose is to determine factors impacting radiologist abdominal pelvic CT exam reporting time. This study was Research Ethics Board approved. Between January 2019 and March 2020, consecutive abdominal pelvic CT exams were documented as structured or unstructured based on application of templates with separate sections for different organs or organ systems. Radiologist reporting location, patient class (inpatient, Emergency Department (ED) patient, outpatient), radiologist fellowship-training, report word count, and radiologist years of experience were documented. Median reporting times were compared using the Wilcoxon Rank-sum test, Kruskal-Wallis test, and regression analysis. Spearman's rank correlation was used to determine correlation between word count and radiologist experience with reporting time. P < 0.05 is defined statistical significance. A total of 3602 abdominal pelvic CT exam reports completed by 33 radiologists were reviewed, including 1150 outpatient and 2452 inpatient and Emergency Department (ED) cases. 1398 of all reports were structured. Median reporting time for structured and unstructured reports did not differ (P = 0.870). Reports dictated in-house were completed faster than reports dictated remotely (P < 0.001), and reports for inpatients/ED patients were completed faster than for outpatients (P < 0.001). Reporting time differences existed between radiologists (P < 0.001) that were not explained by fellowship training (P = 0.762). Median reporting time had a weak correlation with word count (ρ = 0.355) and almost no correlation with radiologist years of experience (ρ = 0.167), P < 0.001. Abdominal pelvic CT reporting is most efficient when dictations are completed in-house and for high-priority cases; the use of structured templates, radiologist fellowship training, and years of experience have no impact on reporting times.

Comparison of MRI features in lipid-rich and lipid-poor adrenal adenomas using subjective and quantitative analysis.

OBJECTIVE: To compare MR-imaging features in benign lipid-rich and lipid-poor adrenal adenomas. MATERIALS AND METHODS: With institutional review board approval, we compared 23 consecutive lipid-poor adenomas (chemical shift [CS] signal intensity [SI] index < 16.5%) imaged with MRI to 29 consecutive lipid-rich adenomas (CS-SI index ≥ 16.5%) imaged during the same time period. A blinded radiologist measured T2-weighted (T2W) SI ratio (adrenal adenoma/psoas muscle), dynamic enhancement wash-in (WI) and wash-out (WO) indices, and T2W texture features. Two blinded Radiologists (R1/R2) assessed T2W-SI (relative to renal cortex) and T2W heterogeneity (using 5-Point Likert scales). Comparisons were performed between groups using independent t tests and Chi-square with Holm-Bonferroni correction. RESULTS: There was no difference in age or gender between groups (p = 0.594, 0.051 respectively). Subjectively, all lipid-rich and lipid-poor adenomas were rated hypointense or isointense compared to renal cortex and T2W-SI did not differ between groups (p = 0.129, 0.124 for R1, R2). Agreement was substantial (Kappa = 0.67). There was no difference in T2W SI ratio (1.8 ± 0.9 [0.5-4.3] lipid rich versus 2.2 ± 1.0 [0.6-4.3] lipid poor, p = 0.139). Enhancement WI and WO did not differ comparing lipid-rich and lipid-poor adenomas (p = 0.759, 0.422 respectively). There was no difference comparing lipid-rich and lipid-poor adenomas T2W heterogeneity judged subjectively (p = 0.695, 0.139 for R1, R2; Kappa = 0.19) or by texture analysis (entropy, kurtosis, skewness; p = 0.134-0.191) with all adenomas except for one rated as mostly or completely homogeneous. CONCLUSIONS: There is no difference in T2W signal intensity, enhancement pattern or T2W heterogeneity judged subjectively or by quantitative texture analysis comparing lipid-poor and lipid-rich adrenal adenomas.

Diagnostic Accuracy of MRI for Differentiation of Benign and Malignant Pancreatic Cystic Lesions Compared to CT and Endoscopic Ultrasound: Systematic Review and Meta-analysis.

BACKGROUND: Differentiation of benign and malignant pancreatic cystic lesions on MRI, computed tomography (CT), and endoscopic ultrasound (EUS) is critical for determining management. PURPOSE: To perform a systematic review evaluating the diagnostic accuracy of MRI for diagnosing malignant pancreatic cystic lesions, and to compare the accuracy of MRI to CT and EUS. STUDY TYPE: Systematic review and meta-analysis. DATA SOURCES: MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Web of Science, and Scopus were searched until February 2020 for studies reporting MRI accuracy for assessing pancreatic cystic lesions. FIELD STRENGTH: 1.5T or 3.0T. ASSESSMENT: Methodologic and outcome data were extracted by two reviewers (AU and MA, 2 years of experience each). All studies of pancreatic cystic lesions on MRI were identified. Studies with incomplete MRI technique were excluded. Risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 tool. STATISTICAL TESTS: Sensitivity/specificity was pooled using bivariate random-effects meta-analysis with 95% confidence intervals (95%CI). Pairwise-comparison of MRI to CT and EUS was performed. The impact of gadolinium-based contrast agents, mucinous lesions, and risk of bias were explored using meta-regression. RESULTS: MRI pooled sensitivity was 76% (95%CI 67% to 84%) and specificity was 80% (95%CI 74% to 85%) for distinguishing benign and malignant lesions. MRI and CT had similar sensitivity (P = 0.822) and specificity (P = 0.096), but MRI was more specific than EUS (80% vs. 75%, P < 0.05). Studies including only contrast-enhanced MRI were more sensitive than those including unenhanced exams (P < 0.05). MRI sensitivity and specificity did not differ for mucinous lesions (P = 0.537 and P = 0.384, respectively) or for studies at risk of bias (P = 0.789 and P = 0.791, respectively). DATA CONCLUSION: MRI and CT demonstrate comparable accuracy for diagnosing malignant pancreatic cystic lesions. EUS is less specific than MRI, which suggests that, in some cases, management should be guided by MRI findings rather than EUS. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY STAGE: 2.

Utility of material-specific fat images derived from rapid-kVp-switch dual-energy renal mass CT for diagnosis of renal angiomyolipoma.

BACKGROUND: Renal angiomyolipoma (AML) are benign masses that require detection of macroscopic fat for accurate diagnosis. PURPOSE: To evaluate fat material-specific images derived from dual-energy computed tomography (DECT) to diagnose renal AML. MATERIAL AND METHODS: This retrospective case-control study evaluated 25 renal AML and 44 solid renal masses (41 renal cell carcinomas, three other tumors) imaged with rapid-kVp-switch DECT (120 kVp non-contrast-enhanced [NECT], 70-keV corticomedullary [CM], and 120-kVp nephrographic [NG]-phase CECT) during 2017-2018. A radiologist measured attenuation (Hounsfield Units [HU]) on NECT, CM-CECT, NG-CECT, and fat concentration (mg/mL) using fat-water base-pair images. RESULTS: At NECT, 100% (44/44) non-AML and 4.0% (1/25) AML measured >-15 HU. At CM-CECT and NG-CECT, 24.0% (6/25) and 20.0% (5/25) AML measured >-15 HU (size 6-20 mm). To diagnose AML, area under receiver operating characteristic curve (AUC) using -15 HU was: 0.98 (95% confidence interval [CI] 0.98-1.00) NECT, 0.88 (95% CI 0.79-0.91) CM-CECT, and 0.90 (95% CI 0.82-0.98) NG-CECT. At DECT, fat concentration was higher in AML (163.7 ± 333.9 [-553.0 to 723.5] vs. -2858.1 ± 460.3 [-2421.2 to -206.0] mg/mL, P<0.001). AUC to diagnose AML using ≥-206.0 mg/mL threshold was 0.98 (95% CI 0.95-1.0) with sensitivity/specificity of 92.0%/96.7%. Of AML, 8.0% (2/25) were incorrectly classified; one of these was fat-poor. AUC was higher for fat concentration compared to HU measurements on CM-CECT and NG-CECT (P=0.009-0.050) and similar to NECT (P=0.98). CONCLUSION: DECT material-specific fat images can help confirm the presence of macroscopic fat in renal AML which may be useful to establish a diagnosis if unenhanced CT is unavailable.

CT and MR imaging of acute adrenal disorders.

The adrenal glands may be overlooked when evaluating acutely ill patients. Acute adrenal disorders may result from complications of an underlying systemic disease, which may be unsuspected clinically. Various acute adrenal emergencies including trauma, spontaneous hemorrhage, infarction and infection can be diagnosed using CT and MRI; however, in uncertain cases follow-up to resolution of imaging findings or histological sampling may be required for diagnosis.

Impact of the COVID-19 pandemic on emergency CT head utilization in Ontario-an observational study of tertiary academic hospitals.

PURPOSE: To determine the impact of the Coronavirus disease-2019 (COVID-19) pandemic on the volume, indications, and results of CT heads performed in the emergency department (ED) at Canadian tertiary academic centers in Ontario. METHODS: A retrospective review of consecutive CT head examinations ordered through the ED during the early stages of the COVID-19 pandemic in Canada (March 12-April 8, 2020) was performed and compared with that during the pre-COVID-19 period (February 12-March 10, 2020). CT reports were reviewed for the exam indication and the presence of predefined acute findings. A two-sample t test was utilized to compare the cohorts. Daily averages were calculated for all measures to control for the sample size difference between each period. A p value < 0.05 was considered significant. RESULTS: Of the total 751 CT head reports, 290 (38.6%) were ordered during the pandemic and 461 (61.4%) were ordered pre-pandemic. The average daily volume of CT head orders decreased significantly during COVID-19 compared with that during pre-COVID-19 (10.4 scans/day vs 16.5 scans/day; p = 0.001). In terms of indications, the frequency of "non-traumatic ICH" was significantly lower during COVID-19 compared with that during pre-COVID-19 (p = 0.01). Also, there was a significant increase in acute findings on CT during COVID-19 compared with that during pre-COVID-19 (p = 0.001). CONCLUSION: The decreased volume of emergency CT heads performed during the COVID-19 pandemic was associated with a significant increase in the proportion of cases with acute findings. This could be a result of the pandemic's influence on the health-seeking behavior of patients as well as the decision-making process of ordering clinicians.

Effect of COVID-19 on computed tomography usage and critical test results in the emergency department: an observational study.

BACKGROUND: The effect of the coronavirus disease 2019 (COVID-19) pandemic on new or unexpected radiologic findings in the emergency department (ED) is unclear. The aim of this study was to determine the effect of the COVID-19 pandemic on the number of computed tomography (CT) critical test results in the ED. METHODS: We performed a retrospective observational study of ED CT usage at 4 Ontario hospitals (1 urban academic, 1 northern academic, 1 urban community and 1 rural community) over 1 month during the COVID-19 pandemic (April 2020) and over the same month 1 year earlier (April 2019; before the pandemic). The CT findings from 1 of the 4 hospitals, Hamilton Health Sciences, were reviewed to determine the number of critical test results by body region. Total CT numbers were compared using Poisson regression and CT yields were compared using the χ2 test. RESULTS: The median number of ED CT examinations per day was markedly lower during the COVID-19 pandemic than before the pandemic (82 v. 133, p < 0.01), with variation across hospitals (p = 0.001). On review of 1717 CT reports from Hamilton Health Sciences, fewer critical test results were demonstrated on CT pulmonary angiograms (43 v. 88, p < 0.001) and CT examinations of the head (82 v. 112, p < 0.03) during the pandemic than before the pandemic; however, the yield of these examinations did not change. Although the absolute number of all CT examinations with critical test results decreased, the number of CT examinations without critical results decreased more, resulting in a higher yield of CT for critical test results during the pandemic (46% [322/696] v. 37% [379/1021], p < 0.01). INTERPRETATION: Emergency department CT volumes markedly decreased during the COVID-19 pandemic, predominantly because there were fewer examinations with new or unexpected findings. This suggests that COVID-19 public information campaigns influenced the behaviours of patients presenting to the ED.

Utility of T2-weighted MRI to Differentiate Adrenal Metastases from Lipid-Poor Adrenal Adenomas.

Purpose: To evaluate T2-weighted MRI features to differentiate adrenal metastases from lipid-poor adenomas. Materials and Methods: With institutional review board approval, this study retrospectively compared 40 consecutive patients (mean age, 66 years ± 10 [standard deviation]) with metastases to 23 patients (mean age, 60 years ± 15) with lipid-poor adenomas at 1.5- and 3-T MRI between June 2016 and March 2019. A blinded radiologist measured T2-weighted signal intensity (SI) ratio (SInodule/SIpsoas muscle), T2-weighted histogram features, and chemical shift SI index. Two blinded radiologists (radiologist 1 and radiologist 2) assessed T2-weighted SI and T2-weighted heterogeneity using five-point Likert scales. Results: Subjectively, T2-weighted SI (P < .001 for radiologist 1 and radiologist 2) and T2-weighted heterogeneity (P < .001, for radiologist 1 and radiologist 2) were higher in metastases compared with adenomas when assessed by both radiologists. Agreement between the radiologists was substantial for T2-weighted SI (Cohen κ = 0.67) and T2-weighted heterogeneity (κ = 0.62). Metastases had higher T2-weighted SI ratio than adenomas (3.6 ± 1.7 [95% confidence interval {CI}: 0.2, 8.2] vs 2.2 ± 1.0 [95% CI: 0.6, 4.3], P < .001) and higher T2-weighted entropy (6.6 ± 0.6 [95% CI: 4.9, 7.5] vs 5.0 ± 0.8 [95% CI: 3.5, 6.6], P < .001). At multivariate analysis, T2-weighted entropy was the best differentiating feature (P < .001). Chemical shift SI index did not differ between metastases and adenomas (P = .748). Area under the receiver operating characteristic curve (AUC) for T2-weighted SI ratio and T2-weighted entropy were 0.76 (95% CI: 0.64, 0.88) and 0.94 (95% CI: 0.88, 0.99). The logistic regression model combining T2-weighted SI ratio with T2-weighted entropy yielded AUC of 0.95 (95% CI: 0.91, 0.99) and did not differ compared with T2-weighted entropy alone (P = .268). There was no difference in logistic regression model accuracy comparing the data by either field strength, 1.5- or 3-T MRI (P > .05). Conclusion: Logistic regression models combining T2-weighted SI and T2-weighted heterogeneity can differentiate metastases from lipid-poor adenomas. Validation of these preliminary results is required.Keywords: Adrenal, MR-Imaging, UrinarySupplemental material is available for this article.© RSNA, 2020.

Characterization of clear cell renal cell carcinoma and other renal tumors: evaluation of dual-energy CT using material-specific iodine and fat imaging.

OBJECTIVE: This study aimed to assess material-specific iodine and fat images for diagnosis of clear cell renal cell carcinoma (cc-RCC) compared to papillary RCC (p-RCC) and other renal masses. MATERIALS AND METHODS: With IRB approval, we identified histologically confirmed solid renal masses that underwent rapid-kVp-switch DECT between 2016 and 2018: 25 cc-RCC (7 low grade versus 18 high grade), 11 p-RCC, and 6 other tumors (2 clear cell papillary RCC, 2 chromophobe RCC, 1 oncocytoma, 1 renal angiomyomatous tumor). A blinded radiologist measured iodine and fat concentration on material-specific iodine-water and fat-water basis pair images. Comparisons were performed between groups using univariate analysis and diagnostic accuracy calculated by ROC. RESULTS: Iodine concentration was higher in cc-RCC (6.14 ± 1.79 mg/mL) compared to p-RCC (1.40 ± 0.54 mg/mL, p < 0.001), but not compared to other tumors (5.0 ± 2.2 mg/mL, p = 0.370). Intratumoral fat was seen in 36.0% (9/25) cc-RCC (309.6 ± 234.3 mg/mL [71.1-762.3 ng/mL]), 9.1% (1/11) papillary RCC (97.11 mg/mL), and no other tumors (p = 0.036). Iodine concentration ≥ 3.99 mg/mL achieved AUC and sensitivity/specificity of 0.88 (CI 0.76-1.00) and 92.31%/82.40% to diagnose cc-RCC. To diagnose p-RCC, iodine concentration ≤ 2.5 mg/mL achieved AUC and sensitivity/specificity of 0.99 (0.98-1.00) and 100%/100%. The presence of intratumoral fat had AUC 0.64 (CI 0.53-0.75) and sensitivity/specificity of 34.6%/93.8% to diagnose cc-RCC. A logistic regression model combining iodine concentration and presence of fat increased AUC to 0.91 (CI 0.81-1.0) with sensitivity/specificity of 80.8%/93.8% to diagnose cc-RCC. CONCLUSION: Iodine concentration values are highly accurate to differentiate clear cell RCC from papillary RCC; however, they overlap with other tumors. Fat-specific images may improve differentiation of clear cell RCC from other avidly enhancing tumors. KEY POINTS: • Clear cell renal cell carcinoma (RCC) has significantly higher iodine concentration than papillary RCC, but there is an overlap in values comparing clear cell RCC to other renal tumors. • Iodine concentration ≤ 2.5 mg/mL is highly accurate to differentiate papillary RCC from clear cell RCC and other renal tumors. • The presence of microscopic fat on material-specific fat images was specific for clear cell RCC, helping to differentiate clear cell RCC from other avidly enhancing renal tumors.

Imaging Manifestations of Acute and Chronic Renal Infection That Mimics Malignancy: How to Make the Diagnosis Using Computed Tomography and Magnetic Resonance Imaging.

PURPOSE: To review the computed tomography and magnetic resonance imaging manifestations of acute and chronic renal infections that may mimic malignancy and to provide useful tips to establish an imaging diagnosis. CONCLUSION: Acute and chronic bacterial pyelonephritis are usually readily diagnosed clinically and on imaging when the diagnosis is suspected based upon clinical presentation. When unsuspected, focal, extensive or mass-like, acute and chronic bacterial pyelonephritis may mimic infiltrative tumours such as urothelial cell carcinoma (UCC), lymphoma, and metastatic disease. Infection may be suspected when patients are young and otherwise healthy when there is marked associated perinephric changes and in the absence of metastatic adenopathy or disease elsewhere in the abdomen and pelvis. Renal abscesses, from bacterial or atypical microbial agents, can appear as complex cystic renal masses mimicking cystic renal cell carcinoma. Associated inflammatory changes in and around the kidney and local invasion favour infection. Emphysematous pyelonephritis can mimic necrotic or fistulizing tumour; however, infection is more likely and should always be considered first. Xanthogranulomatous pyelonephritis can mimic malignancy when focal or multifocal and in cases without associated renal calculi. Malacoplakia is an inflammatory process that may mimic malignancy and should be considered in patients with chronic infection. Bacillus Calmette-Guerin (BCG)-induced pyelonephritis is rare but can mimic renal malignancy and should be considered in patients presenting with a renal mass when being treated with BCG for urinary bladder UCC.

Update on MR urography (MRU): technique and clinical applications.

Magnetic resonance imaging of the upper tract (pyelocalyces and ureters) or MR Urography (MRU) is technically possible and when performed correctly offers similar visualization of the upper tracts and for detection of non-calculous diseases of the collecting system similar specificity but with lower sensitivity compared to CTU. MRU provides the ability to simultaneously image the kidneys and urinary bladder with improved soft tissue resolution, better tissue characterization and when combined with assessment of the upper tract, a comprehensive examination of the urinary system. MRU requires meticulous attention to technical details and is a longer more demanding examination compared to CTU. Advances in MR imaging techniques including: parallel imaging, free-breathing motion compensation techniques and compressed sensing can dramatically shorten examination times and improve image quality and patient tolerance for the exam. This review article discusses updates in the MRU technique, summarizes clinical indications and opportunities for MRU in clinical practice and reviews advantages and disadvantages of MRU compared to CTU.

Disseminated cysticercosis: role of whole body Magnetic Resonance Imaging.

UNLABELLED: Cysticercercosis is a parasitic infection that is commonly seen in developing countries. Treatment of cysticercosis can precipitate an intense inflammatory response which may further worsen the symptoms. Whole body MRI is an upcoming tool for screening of diseases. It can be acquired in the same setting as a brain MRI in reasonable time without any additional hardware. We present a case wherein whole body MRI was used to evaluate disseminated cysticercosis. It can prove as useful screening tool to gauge the disease load and modify the treatment plan accordingly, especially in endemic areas. KEY WORDS: disseminated cysticercosis, whole body MRI.

Solitary osseous metastasis of rectal carcinoma masquerading as osteogenic sarcoma on post-chemotherapy imaging: a case report.

Solitary metastases from colorectal carcinoma in the absence of hepatic or pulmonary metastases are rare. These can have a diverse imaging appearance, particularly after chemotherapy. It is important identify patients with solitary skeletal metastases, as they have a better prognosis than those with multiple skeletal or visceral metastases. We describe an unusual case of a solitary metastasis to the femur in a case of colon carcinoma that went undiagnosed and later presented with imaging features of osteogenic sarcoma.

Usefulness of three-dimensional navigable intraoperative ultrasound in resection of brain tumors with a special emphasis on malignant gliomas.

BACKGROUND: Intraoperative imaging is increasingly being used in resection of brain tumors. Navigable three-dimensional (3D)-ultrasound is a novel tool for planning and guiding such resections. We review our experience with this system and analyze our initial results, especially with respect to malignant gliomas. METHODS: A prospective database for all patients undergoing sononavigation-guided surgery at our center since this surgery's introduction in June 2011 was queried to retrieve clinical data and technical parameters. Imaging was reviewed to categorize tumors based on enhancement and resectability. Extent of resection was also assessed. RESULTS: Ninety cases were operated and included in this analysis, 75 % being gliomas. The 3D ultrasound mode was used in 87 % cases (alone in 40, and combined in 38 cases). Use of combined mode function [ultrasound (US) with magnetic resonance (MR) images] facilitated orientation of anatomical data. Intraoperative power Doppler angiography was used in one-third of the cases, and was extremely beneficial in delineating the vascular anatomy in real-time. Mean duration of surgery was 4.4 hours. Image resolution was good or moderate in about 88 % cases. The use of the intraoperative imaging prompted further resection in 59 % cases. In the malignant gliomas (51 cases), gross-total resection was achieved in 47 % cases, increasing to 88 % in the "resectable" subgroup. CONCLUSIONS: Navigable 3D US is a versatile, useful and reliable intraoperative imaging tool in resection of brain tumors, especially in resource-constrained settings where Intraoperative MR (IOMR) is not available. It has multiple functionalities that can be tailored to suit the procedure and the experience of the surgeon.

Diagnosis of a malignant intramammary node retrospectively aided by mastectomy specimen MRI-Is the search worth it? A case report and review of current literature.

Metastases to intramammary nodes have been shown to be an independent predictor of poor outcome in patients with breast cancer, such as axillary lymph node metastases. The detection and accurate characterization of these nodes preoperatively is thus crucial for the staging and planning of treatment for breast carcinoma, particularly in cases with axillary lymph node negative disease as it upgrades the disease staging. We herein report the first case where we detected an intra-mammary node on specimen MRI after the primary pathological gross specimen evaluation failed to detect the node.