Articles
Articles are a collaborative effort to provide a single canonical page on all topics relevant to the practice of radiology. As such, articles are written and continuously improved upon by countless contributing members. Our dedicated editors oversee each edit for accuracy and style. Find out more about articles.
More than 200 results
Article
Cystic renal dysplasia
Cystic renal dysplasia refers to a subgroup of congenital anomalies of the kidney and urinary tract characterized by the dysplastic renal parenchyma and formation of cysts. The most severe form is multicystic dysplastic kidney, in which functional renal parenchyma is absent and only undifferenti...
Article
Neuroblastoma
Neuroblastomas are tumors of neuroblastic origin. Although they may occur anywhere along the sympathetic chain, the vast majority arise from the adrenal gland.
They represent the most common extracranial solid childhood malignancy and are the third most common childhood tumor after leukemia and...
Article
Perinephric stranding
Perinephric stranding refers to the appearance of edema within the fat of the perirenal space on CT or MRI. While a degree of symmetric bilateral perinephric stranding is common, particularly in the elderly, asymmetric or unilateral perinephric stranding is an important sign of renal inflammatio...
Article
Testicular torsion
Testicular torsion occurs when a testis torts on the spermatic cord resulting in the cutting off of blood supply. The most common symptom is acute testicular pain and the most common underlying cause, a bell-clapper deformity. The diagnosis is often made clinically but if it is in doubt, an ultr...
Article
Ascites
Ascites (hydroperitoneum is a rare synonym) is defined as an abnormal amount of intraperitoneal fluid.
Terminology
Ascites (plural is the same word) tends to be reserved for relatively sizable amounts of peritoneal fluid. The amount has not been defined formally. It is noted physiologically, h...
Article
Ciliopathies
Ciliopathies refer to diseases due to malfunctioning cilia (singular: cilium). Cilia are organelles that are external extensions of the cell membrane. Cilia fall into two main types: primary (or immotile) cilia and motile cilia.
Clinical presentation
Primary cilia are found in virtually every...
Article
Adrenal metastasis
Adrenal metastases are the most common malignant lesions involving the adrenal gland. Metastases are usually bilateral but may also be unilateral. Unilateral involvement is more prevalent on the left side (ratio of 1.5:1).
Epidemiology
They are present at autopsy in up to 27% of patients with ...
Article
Ductus deferens
The ductus deferens (plural: ductus deferentes), formerly known as the vas deferens (plural: vasa deferentia), forms part of the male internal genitalia where it transports sperm from the epididymis to the ejaculatory duct.
Terminology
In modern anatomic nomenclature, it is no longer referred ...
Article
Primary cutaneous melanoma
Primary cutaneous melanoma is the most common subtype of melanoma, a malignant neoplasm that arises from melanocytes. Melanocytes predominantly occur in the basal layer of the epidermis but do occur elsewhere in the body. Primary cutaneous melanoma is by far the most common type of primary melan...
Article
Excretory phase
The excretory phase also known as the urographic phase is a postcontrast injection time range in which there is an optimal enhancement of the renal collecting systems.
Technique
The acquisition time depends on the intravenous device (central or peripheral), the concentration of the contrast me...
Article
Adrenal vein sampling
Adrenal vein sampling (AVS) is a procedure where blood is collected from the adrenal veins via catheter to confirm autonomous hormone production, if it is unilateral or bilateral, and to guide further treatment 1. If unilateral, the adrenal gland can be removed by surgery; thus curing secondary ...
Article
Extrapulmonary tuberculosis
Extrapulmonary tuberculosis (TB) refers to the hematogenous spread of Mycobacterium tuberculosis.
Pathology
Extrapulmonary tuberculosis can occur as a primary form of the disease, i.e. direct infection of an extrapulmonary organ without the presence of primary pulmonary tuberculosis or it can ...
Article
Benign prostatic hyperplasia
Benign prostatic hyperplasia (BPH), also known as benign prostatic enlargement (BPE), is an extremely common condition in elderly males and a major cause of bladder outflow obstruction.
Terminology
The term benign prostatic hypertrophy was formerly used for this condition, but since histology...
Article
Hematuria (adult)
Hematuria occurs when blood enters the urinary collecting system and is excreted in the urine. There are many etiologies for hematuria, and they range from benign and transient to gravely concerning. Hematuria can derive from the kidneys, ureters, bladder, prostate (in men), or urethra. Imaging ...
Article
Isthmus (disambiguation)
Isthmus (plural: isthmi) is an anatomical term and refers to a slender structure joining two larger components. Some of these uses of the word isthmus are now rarely used or only seen in older texts and articles:
isthmus (aorta)
isthmus (auditory tube)
isthmus (auricle of the ear)
isthmus (c...
Article
Pancake kidney
Pancake kidney (also known as discoid kidney, disc kidney, lump kidney, fused pelvic kidney or cake kidney) is a rare renal fusion anomaly of the kidneys of the crossed fused variety.
Clinical presentation
Pancake kidney may be an incidental finding. However, they can present clinically becaus...
Article
Zinner syndrome
Zinner syndrome is a triad of mesonephric (Wolffian) duct anomalies comprising unilateral renal agenesis, ipsilateral seminal vesicle cyst, and ejaculatory duct obstruction 1.
Epidemiology
The condition is very rare, with ~200 reported cases (c. 2009) 9.
Clinical presentation
Patients are ty...
Article
Echogenic renal pyramids (differential)
Echogenic renal pyramids in children can be due to many different causes.
Differential diagnosis
Nephrocalcinosis
Iatrogenic (most common cause)
furosemide (frusemide)
vitamin D
steroids
Non-iatrogenic
idiopathic hypercalcemia
Williams syndrome
hyperparathyroidism
milk-alkali syndrom...
Article
Cobb collar
Cobb collar, also known as a Moormann ring or congenital narrowing of the bulbar urethra, is a membranous stricture of the bulbar urethra just downstream of the external urethral sphincter. It is sometimes referred to as a type III posterior urethral valve (PUV), and does not maintain a connecti...
Article
Renal papillary necrosis
Renal papillary necrosis refers to ischemic necrosis of the renal papillae. Necrosis also occurs in the medullary pyramids.
Clinical presentation
Patients can present with both acute episodes or chronic renal papillary necrosis. Calyceal or ureteral obstruction by sloughed papillae manifests w...