Recent technical advances in computed tomography (CT) and magnetic resonance imaging (MRI) have resulted in improved detection of subtle changes in adrenal gland morphology. The different morphologic patterns of adrenal gland enlargement on imaging can be classified as follows (…
Etiology Urinary tract anomalies encompass a wide range of abnormalities from the multiple varied components of the urinary tract—the renal parenchyma, the collecting system, the bladder, the urethra, and the vasculature. Anomalies result from alterations in the normal embryologic development…
The urinary bladder is composed of the following four layers: 1. Urothelium: Transitional epithelium 2. Lamina propria: Vascular layer of connective tissue deep to the urothelium 3. Muscularis propria: Detrusor muscle 4. Adventitia: Connective tissue The bladder is an extraperitoneal…
A ureteral stricture is a narrowing of the ureter that results in a functional obstruction. It may be the result of a variety of benign and malignant causes, which may be classified as intrinsic or extrinsic processes. The clinical presentation…
Etiology Urinary tract obstruction (UTO) is a syndrome that may be caused by a wide range of pathologic processes. It may vary in the following: Degree: May be partial or complete. Site: May be unilateral or bilateral and may occur…
Renovascular Hypertension Etiology The most common cause of renovascular hypertension is renal artery stenosis, which may be caused by atherosclerosis (70% to 90%) or less commonly by fibromuscular dysplasia (10% to 30%). Rare causes of renal artery stenosis include arteritis,…
Renal failure may be classified as prerenal when secondary to a reduction in the renal perfusion pressure gradient, renal when the result of intrinsic disease of the renal parenchyma, and postrenal when secondary to an abnormality of urine outflow. Prerenal…
This chapter discusses benign and malignant renal lesions ( Box 63-1 ) with a separate note on cystic lesions based on the Bosniak classification. Box 63-1 Benign and Malignant Focal Renal Lesions Benign Lesions Simple renal cyst Oncocytoma Angiomyolipoma Leiomyoma…
Anatomy Overview The Kidney The kidneys are paired retroperitoneal organs that primarily function in the excretion of metabolic waste. They are bean shaped with a convex lateral border and a concave medial surface known as the renal hilum. On intravenous…
Lymph Node Imaging Techniques Imaging evaluation of lymph nodes forms an integral component of staging of various malignancies, including lymphomas, and is also helpful in the evaluation of certain infective and inflammatory processes within the abdomen. This has special relevance…