CT findings and diagnostic performance of upper urinary tract carcinoma in situ.

Objectives: To evaluate the CT characteristics and detectability of carcinoma in situ (CIS) of the upper urinary tract.

Methods: Between January 2007 and March 2020, 28 patients (mean age: 73 years, 25 male and 3 female) with 29 pure CIS lesions of the upper urinary tract (i.e.

CT and MR imaging for solid renal mass characterization.

As our understanding has expanded that relatively large fraction of incidentally discovered renal masses, especially in small size, are benign or indolent even if malignant, there is growing acceptance of more conservative management including active surveillance for small renal masses. As for advanced renal cell carcinomas (RCCs), nonsurgical and subtype specific treatment options such as immunotherapy and targeted therapy is developing. On these backgrounds, renal mass characterization including differentiation of benign from malignant tumors, RCC subtyping and prediction of RCC aggressiveness is receiving much attention and a variety of imaging techniques and analytic methods are being investigated.

Differentiation of Benign From Metastatic Adrenal Masses in Patients With Renal Cell Carcinoma on Contrast-Enhanced CT.

Objective: The purpose of this article was to determine whether imaging features on contrast-enhanced CT can differentiate benign from metastatic adrenal masses in patients with renal cell carcinoma (RCC).

Materials And Methods: Between January 2008 and January 2014, 135 patients with untreated RCC were found to have 163 adrenal masses (102 benign and 61 metastatic) on contrast-enhanced CT including the corticomedullary phase (66 benign and 42 metastatic) or nephrographic phase (56 benign and 33 metastatic) or both. Imaging features of renal and adrenal masses were recorded, including T and N staging components of renal masses, internal texture, CT attenuation values, and attenuation differences between renal and adrenal masses.

CT negative attenuation pixel distribution and texture analysis for detection of fat in small angiomyolipoma on unenhanced CT.

Purpose: The purpose of the paper is to evaluate if CT pixel distribution and texture analysis can identify fat in angiomyolipoma (AML) on unenhanced CT.

Methods: Thirty-seven patients with 38 AMLs and 75 patients with 83 renal cell carcinomas (RCCs) were evaluated. Region of interest (ROI) was manually placed over renal mass on unenhanced CT.

Small (< 4 cm) Renal Masses: Differentiation of Angiomyolipoma Without Visible Fat From Renal Cell Carcinoma Using Unenhanced and Contrast-Enhanced CT.

Objective: The purpose of this study was to evaluate if small (< 4 cm) angiomyolipoma without visible fat can be differentiated from renal cell carcinoma (RCC) using contrast-enhanced CT alone and using unenhanced and contrast-enhanced CT in combination.

Materials And Methods: Twenty-three patients with 24 angiomyolipomas without visible fat and 130 patients with 148 RCCs underwent unenhanced and contrast-enhanced CT. Demographic data and size, shape, CT attenuation, and heterogeneity (entropy and subjective score) of the renal mass on unenhanced CT and contrast-enhanced CT were recorded.

Small (< 4 cm) Renal Mass: Differentiation of Oncocytoma From Renal Cell Carcinoma on Biphasic Contrast-Enhanced CT.

Objective: The purpose of this study was to evaluate whether small (< 4 cm) oncocytomas can be differentiated from renal cell carcinomas (RCCs) on biphasic contrast-enhanced CT.

Materials And Methods: Forty-three patients with 53 oncocytomas and 123 patients with 128 RCCs (24 papillary subtype and 104 clear cell and other subtypes) who underwent biphasic contrast-enhanced CT were included in the study. Patient demographics and CT tumor characteristics were evaluated in each case.

MRI Findings of Inverted Urothelial Papilloma of the Bladder.

Objective: The objective of this study was to characterize MRI findings of inverted urothelial papilloma of the bladder.

Materials And Methods: Data pertaining to 16 patients with 18 pathologically proven inverted urothelial papillomas of the bladder who had undergone MRI were retrospectively collected from seven institutions. The shape and surface characteristics of the tumors were evaluated using T2-weighted MR images.

Retrospective analysis of contrast-enhanced computed tomographic findings related to obstructive shock due to ascending aortic dissection.

Objective: The objective of this study was to evaluate contrastenhanced computed tomography findings related to obstructive shock due to ascending aortic dissection (AAD).

Methods: The computed tomography findings in 9 AAD patients with shock, 11 AAD patients without shock, and 18 control subjects were evaluated for (1) pericardial effusion, (2) diameter of the inferior vena cava, (3) periportal hypodensity, (4) retrograde reflux of contrast material, (5) aortic and visceral enhancement, and (6) other factors (peripancreatic edema, bowel thickening/dilatation).

Results: Patients with shock showed the highest ratio of pericardial effusion, periportal hypodensity, and retrograde reflux of contrast material; largest inferior vena cava diameter; stronger aortic enhancement in both the arterial and portal phases; lowered splenic and pancreatic enhancement in the arterial phase; and stronger visceral (especially adrenal) enhancement, except for the renal medulla in the portal phase.