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BACKGROUNDThe objective of this study was to determine the accuracy, reproducibility, and clinical value of magnetic resonance (MR)‐guided, vacuum‐assisted breast biopsy (MR‐VAB) in a prospective, multicenter study.METHODSIn 5 European centers, MR‐VAB was performed or attempted on 538 suspicious lesions that were visible or could targeted only by MR imaging (MRI). Verification of malignant or borderline lesions included reexcision of the biopsy cavity. Benign biopsy results were verified by retrospective correlation of histology with preinterventional and postinterventional MRI studies. Follow‐up of 24–48 months (median, 32 months) was available for 491 of 538 patients.RESULTSMR‐VAB was unsuccessful or was not completed in 21 of 538 patients, for which an immediate repeat biopsy was recommended. Five hundred seventeen of 538 performed VAB procedures (96%) were successful. Histology yielded 138 (27%) malignancies, 17 (3%) atypical ductal hyperplasias, and 362 (70%) benign entities. No false‐negative diagnoses occurred among the 517 successful MR‐VAB procedures. The positive predictive value of VAB depended on patient preselection, which differed according to the indication for the initial MRI study.CONCLUSIONSThe results of this study indicated that MR‐VAB offers excellent accuracy. Small lesion size did not prove to be a limitation. Cancer 2006. © 2006 American Cancer Society.

Conclusion: In general, ADC values are not useful in differentiating adrenal lesions. However, when ADC values are applied to lesions that are indeterminate on signal intensity index, they may help in differentiating a subset of benign and malignant lesions. Editorial CommentAdrenal incidentalomas are found in about 6% of patients submitted to abdominal computed tomography. Based on distinct radiologic criteria classified as morphologic (size, shape, rate of growing), histologic (lipid content of the mass on CT without contrast or on chemical-shift imaging on MRI without contrast) and physiologic (absolute washout of contrast on CT), the vast majority of adrenal incidentalomas are adequately characterized as a benign or malignant. Lipid rich adrenal adenoma loses signal intensity when protons from water and fat are on opposed-phase in comparison with imaging when these protons are inphase. Signal intensity index higher than 16.5% is usually found in benign adenomas. Indeterminate adrenal lesion represents a lesion with signal intensity index below 16.5%. In such situation, the authors showed that use of ADC values obtained with diffusion-weighted imaging (DWI) might be useful in differentiating benign from malignant adrenal lesions.Although in our protocol for DWI of adrenal masses we use a different "b-value" (b-factor of 1000), we have found no utility of DWI even in this selected group of patients with indeterminate lesion on CSI. Actually we have seen two out of 13 adrenal adenomas showing the lowest ADC values. As pointed out by the authors, the different proportion of lipid-poor adenomas and fat-containing adrenal metastases may explain distinct results with DWI. Roentgenol. 2011; 197: 887-96 Objective: The purpose of this study was to evaluate the diagnostic performance of CT in determining whether a small solid renal enhancing mass is benign or malignant. Materials and Methods: Ninety-nine biopsies of enhancing solid renal masses 4 cm or smaller without fat on CT scans were performed under CT fluoroscopic guidance. The growth pattern, interface with parenchyma, presence of a scar and segmental inversion enhancement, unenhanced CT histogram, and pattern and degree of enhancement on triphasic MDCT images were independently evaluated by two radiologists. Biopsy and pathology reports were used as the reference standard, and imaging follow-up of benign lesions was performed for at least 1 year. Statistical analysis was performed to determine the significance of CT criteria in differentiating malignant from benign lesions. Results: Of the 99 lesions, 74 (75%) were malignant at biopsy, and 25 (25%) were benign. Lesions with gradual enhancement were more likely to be benign. No significant correlation was found between other CT Dr. Adilson Prando

Much clinical research on osteoporosis is aimed at documenting a reduction in vertebral fracture rates, but there is considerable disagreement about defining normality. Most methods for measuring vertebral body dimensions use lateral radiographs. In the present paper, we investigate the reliability of magnetic resonance imaging (MRI) for normal reference determination. A validation study was performed on a cadaver by comparing vertebral body volume measured both with MRI (sagittal acquisition in T1 weighted sequence) and with immersion. MRI was then performed with the same protocol from T4 to L5 in a standard population of 80 women with no history of vertebral fractures. Then all vertebral measurements were standardized relative to each other, and means and standard deviations were calculated using a statistical fitting procedure derived from volume and medial area. The validation study confirmed the reproducibility and accuracy of MRI (intraclass correlation coefficient 0.95). There was a strong correlation between volume and medial area of vertebral bodies (Pearson correlation coefficient 0.95) and a constant relationship between the medial area of vertebral bodies for each subject (coefficient of variation 5.6%). The variations in vertebral body dimensions will allow comparison with pathologic vertebral fractures in further studies. This could be useful for monitoring osteoporosis treatments.

A rare case of Alcock's syndrome caused by tumoral compression of the pudendal nerve is reported. Spine surgeons must be aware of the possibility of Alcock's syndrome in patients presenting with atypical sciatica.