Characterization of adrenal masses with diffusion-weighted imaging

Abstract

Urological Survey 788 Editorial CommentLaparoscopic live donor nephrectomy (LDN) has become the standard of care at most major academic centers. The benefits of laparoscopic over open donor nephrectomy have extensively been demonstrated since the first report by Kavoussi et al. Recently, the LESS Urological procedures are gaining popularity.The authors studied 50 consecutive LESS-DN patients versus a matched cohort of 50 LDN patients. They demonstrated that LESS-DN patients recovered faster and complications were comparable with equal graft function and warm ischemia time. This report is valuable since convalescence and recovery is pivotal variables that may influence the decision to become a kidney donor increasing the pool of donors for the current high demand. The Gelport was used in this study that may also facilitate the learning curve compared to other single ports. Roentgenol. 2011; 197: 132-8 Objective: The purpose of this article is to assess the role of diffusion-weighted MRI in characterizing adrenal masses. Materials and Methods: A retrospective review of the MRI database from August 2007 to July 2009 was performed. The MRI examinations of 48 patients, with 49 lesions, were reviewed independently and blindly by two experienced abdominal radiologists who measured the signal intensities on in-phase and opposed-phase T1-weighted imaging and apparent diffusion coefficient (ADC). ADC measurements and quantitative parameters of chemical shift imaging (signal intensity index and adrenal-to-spleen ratio) were assessed separately and in combination. Lesions with indeterminate signal intensity index (< 16.5%) were considered benign if ADC was greater than or equal to 1.0 × 10(-3) mm(2)/s and malignant if ADC was less than 1.0 × 10(-3) mm(2)/s. Stepwise logistic regression analysis and receiver operating characteristic curves analysis were performed. Results: There were 12 malignant and 37 benign lesions. On multivariate analysis, the only significant predictors of lesion status were signal intensity index from reviewer 2 (p = 0.05) and lesion size (p = 0.04); ADC values were not found to be useful. On receiver operating characteristic curve analysis, there was no significant difference in area under the curve for ADC, signal intensity index, adrenal-to-spleen ratio, or the combined signal intensity index and ADC assessment. For lesions that were indeterminate according to signal intensity index, ADC values greater than 1.50 × 10(-3) mm(2)/s were found only in benign lesions, and nine of 11 lesions with ADC less than 1.0 × 10(-3) mm(2)/s were malignant.

Optimal and novel imaging of the adrenal glands

“…Currently, the most valid method in MRI imaging for this purpose is chemical shift imaging (CSI). Multiple older studies have assessed morphology on standard imaging sequences, texture analysis, enhancement characteristics and diffusion weighted imaging with mixed results [29 ▪ ,30–33].…”

Pitfalls and differential diagnosis on adrenal lesions: current concepts in CT/MR imaging: a narrative review

“…Hemangioma are classified into 4 types: cavernous, venous, capillary type and mixed (46). On CT, hemangiomas can be homogeneous, even if in larger lesions is possible to discover calcifications which indicate previous hemorrhages (47).…”

Diagnostic performances of FDG-PET/CT and diffusion-weighted imaging indices for differentiating benign pheochromocytoma from other benign adrenal tumors

“…Despite previous investigational efforts, the usefulness of DWI in characterizing adrenal tumors has not been established [14][15][16][17][18]. In particular, only a few reports have described DWI for pheochromocytoma [18,19], and the value of this modality in differentiating between pheochromocytoma and other benign adrenal tumors is largely unknown.…”