Follow-up for Bosniak category 2F cystic renal lesions.

Purpose: To determine percentage of Bosniak category 2F complex cystic renal masses that progress to malignancy based on serial follow-up studies,and to determine if there are demographic and/or imaging features associated with progression.

Materials And Methods: This retrospective study was institutional review board-approved with waiver of informed consent. Hospital database system was searched from January 1, 1996, to May 1, 2011, for category 2F cysts studied with contrast agent-enhanced computed tomography or magnetic resonance imaging and followed with serial contrast-enhanced imaging.

MDCT urography with high-volume low-concentration i.v. contrast material, peroral hydration, i.v. furosemide, and i.v. saline: qualitative and quantitative assessment in 100 consecutive patients.

Objective: The purpose of this study is to qualitatively and quantitatively assess MDCT urography performed with a high volume of low-concentration (240 mg I/mL) i.v. contrast agent supplemented with peroral hydration, i.

The Bosniak renal cyst classification: 25 years later.

In the past 25 years, there have been continuous advances in the diagnosis of disease throughout the body owing to the introduction of new technology and the experience gained with its use. However, the imaging and evaluation of complicated cystic lesions of the kidneys frequently remains a difficult problem. The classification of renal cystic lesions suggested 25 years ago, now referred to as the Bosniak renal cyst classification, remains pertinent to the diagnosis and management of these difficult-to-diagnose complicated cystic masses.

Multilocular cystic renal cell carcinoma: comparison of imaging and pathologic findings.

Objective: The purpose of this study was to retrospectively correlate the imaging and pathologic features of multilocular cystic renal cell carcinoma (RCC), a low-grade neoplasm that has an excellent prognosis.

Materials And Methods: Institutional databases were searched for the period between 2001 and 2010 to identify cases of resected renal tumors that had been evaluated with CT or MRI and been analyzed by a uropathologist to confirm the histologic diagnosis of multilocular cystic RCC. The images (nine CT, 14 MRI) were reviewed, and a Bosniak cyst category was assigned.

MRI findings of angiomyolipoma of the renal sinus in 5 cases.

The magnetic resonance imaging (MRI) appearance of 5 cases of angiomyolipoma (AML) centered in the renal sinus is presented. All cases exhibited similar imaging findings, including well-circumscribed margins, minimal perceived enhancement without soft tissue components, insinuation around the renal collecting system, and localized hydrocalicosis with associated localized renal parenchymal atrophy but without generalized hydronephrosis. Findings in some cases included extension out of the renal sinus and presence of aneurysmal vessels.

Pitfalls in renal mass evaluation and how to avoid them.

Characterization of renal masses with computed tomography (CT) and magnetic resonance (MR) imaging is usually clear-cut and accurate. However, potential pitfalls exist in diagnosis of renal masses, and it is necessary to understand these pitfalls to avoid misdiagnosis and possibly unnecessary surgery. Although some of the pitfalls are related to technical factors of the CT and MR imaging equipment, others are related to errors in image interpretation.

CT and MR imaging of complications of partial nephrectomy.

The standard treatment for renal cell carcinoma for many years was radical nephrectomy, but in the past decade there has been a trend toward elective nephron-sparing surgery. Initially, partial nephrectomy was performed with an open surgical approach; more recently and with increasing frequency, a laparoscopic approach has been used in selected cases. Nephron-sparing surgery with either approach is more complex than is traditional radical nephrectomy and more frequently results in complications.

How I do it: evaluating renal masses.

With modern computed tomography (CT) and magnetic resonance (MR) imaging equipment, the diagnosis of most renal masses is usually straightforward and accurate. The major question to be answered is whether the mass represents a surgical or nonsurgical lesion or, in some cases, if follow-up studies are necessary. This evaluation usually can be accomplished if a high-quality examination is performed, if the clinical history of the patient is kept in mind, if conditions that mimic a renal neoplasm are considered and excluded, and if there is an awareness of the potential pitfalls and limitations of CT and MR imaging.

MR imaging of cystic renal masses.

MR imaging has proven to be an important imaging modality in the evaluation of cystic renal masses. Because it is becoming more widely used, it is necessary to be able to characterize cystic renal masses accurately using MR imaging alone. We review the indications for the use of MR imaging and discuss the findings present in a variety of cystic renal masses.

Evaluation of cystic renal masses: comparison of CT and MR imaging by using the Bosniak classification system.

Purpose: To compare computed tomography (CT) and magnetic resonance (MR) imaging in the evaluation of cystic renal masses by using the Bosniak classification system.

Materials And Methods: Images of 69 renal masses in 59 patients (38 men, 21 women; mean age, 60.4 years; range, 30-86 years), who had undergone both CT and MR imaging examinations within 1 year (average, 60.

Renal imaging for diagnosis and staging of renal cell carcinoma.

The development and expansion of CT and MRI technology have enhanced the detection and characterization of renal lesions. Although these advancements should lead to earlier diagnosis of renal cell carcinoma with subsequent improved cure rates, the increased imaging has also uncovered many cases that are problematic not only in diagnosis but in management as well. The performance of high-quality examinations combined with growing experience should improve the ability to diagnose and manage these cases successfully.

Follow-up CT of moderately complex cystic lesions of the kidney (Bosniak category IIF).

Objective: The purpose of this study is to show the use of follow-up CT studies in the management of moderately complex cystic lesions of the kidney (Bosniak category IIF).

Materials And Methods: The CT scans of 42 moderately complex cystic renal masses (Bosniak category IIF) with follow-up examinations for 2 years or greater or with pathology correlation (n = 3) were retrospectively analyzed by the authors in consensus. The complexity of each lesion was assessed on the basis of the number and appearance of the septa, wall thickness, interface with the kidney parenchyma, presence and amount of calcification, and contrast enhancement characteristics.

Calcification in cystic renal masses: is it important in diagnosis?

Purpose: To determine whether the presence of calcifications in cystic renal masses is important in diagnosis and to suggest an approach to the management of calcified cystic renal masses.

Materials And Methods: Eighty-one cystic renal masses containing calcification in a wall or septum were evaluated by means of review of computed tomographic (CT) images (n = 81), follow-up CT images (n = 28), and results of pathologic examination (n = 40) by the authors in consensus. Images were evaluated for lesion size, amount and morphology of calcification, and any association of calcification with soft-tissue structures.

CT differentiation of large exophytic renal angiomyolipomas and perirenal liposarcomas.

Objective: The purpose of our study was to describe the imaging findings and CT characteristics that lead to accurate distinction of large exophytic renal angiomyolipomas from retroperitoneal perirenal liposarcomas, which at times can be confused on imaging studies and even at pathologic examination.

Materials And Methods: We retrospectively analyzed CT images of 15 large exophytic renal angiomyolipomas and 12 well-differentiated perirenal liposarcomas. Pathologic correlation was available for six of 15 angiomyolipomas and all of the liposarcomas.