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18 results found

Adrenal washout

Adrenal washout can be calculated using the density value of an adrenal mass on non-enhanced, portal venous phase and 15 minutes delayed CT scans (density measured in Hounsfield units (HU)). It is primarily used to diagnose adrenal adenoma. absolute washout [(HUportal venous phase) - (HUdelaye...

CT cystography

CT cystography is a variation of the traditional fluoroscopic cystogram. Instead of anterograde opacification of the urinary collecting system (as with CT urography), contrast is instilled retrograde into the patient's bladder, and then the pelvis is imaged with CT. Indications suspected bladd...


Cystography is a fluoroscopic study that images the bladder. It is similar to a voiding cystourethrogram (VCUG), and the difference between the studies is primarily one of emphasis; a cystogram focuses on the bladder and a VCUG focuses on the posterior urethra. The study has been adapted to CT a...


Hematospermia (less commonly hemospermia) refers to the presence of blood in semen or ejaculatory fluid. It is a symptom that can cause great anxiety in patients despite usually being of benign etiology. Pathology Etiology Benign urogenital infections including sexually transmitted disease, ...

Hematuria (pediatric)

Hematuria in a child is evaluated differently than in an adult in two main respects: there is a lower likelihood of a malignancy (renal or bladder) causing the hematuria preference is given to nonionizing radiation Pathology Hematuria can be considered in three main forms: "gross" hematuria...

Hemorrhage exclusion sign (prostate)

The hemorrhage exclusion sign can be a useful MRI finding following prostate biopsy. Pathology The normal prostate produces high concentrations of citrate, which among other properties, acts as an anticoagulant 1. As tumor cells are dysfunctional, they will produce lower levels of citrate than...

Management of Incidental Adrenal Masses: American College of Radiology white paper

The Management of Incidental Adrenal Masses revised in 2017 by the Adrenal Subcommittee of the Incidental Findings Committee of the American College of Radiology is an algorithm for the management of patients who are: adults (i.e. 18-year-old or over) asymptomatic for adrenal pathology referr...

Pediatric urinary tract infection (NICE guideline)

The British National Institute for Health and Care Excellence (NICE) published the “Urinary tract infection in under 16s: diagnosis and management” in 2007 as a guideline for pediatric urinary tract infection (UTI) management, including imaging, prophylaxis and follow-up 1.  This article intend...

Penile Doppler in erectile dysfunction

Penile Doppler in erectile dysfunction or papaverine-induced color duplex Doppler, is a highly accurate means of assessing patients with erectile dysfunction (ED). Pathology Penile erection is a result of a complex interaction between the nervous, arterial, venous and sinusoidal systems. Any d...

Renal artery stenosis

Renal artery stenosis (RAS) refers to a narrowing of a renal artery. When the process occurs slowly, it leads to secondary hypertension. Acute renal artery stenosis does not lead to hypersecretion of renin. Pathology When the stenosis occurs slowly, collateral vessels form and supply the kidne...

Renal transplant ultrasound

The central approach of renal transplant ultrasound is to evaluate for possibly treatable surgical or medical complications arising in the transplanted kidney. Institutions vary in the exact schedule of renal transplant ultrasound assessment, but it is common to obtain an initial ultrasound 24-...

Scrotal scintigraphy

Scrotal scintigraphy is a radio-isotope examination of the scrotal contents, primarily in patients presenting with scrotal pain. Indications Although, ultrasound remains the mainstay of scrotal imaging, scintigraphy can be used where the diagnosis is unclear, since ultrasound appearances for s...

Split bolus technique

The split bolus technique is a CT imaging investigation used in patients with hematuria aiming to put together, in a single image acquisition, both the nephrographic and renal excretory phases and thus reducing the radiation dose of the study. It is a CT protocol adopted for some institutions fo...

Testicular and scrotal ultrasound

Testicular and scrotal ultrasound is the primary modality for imaging most of the male reproductive system. It is relatively quick, relatively inexpensive, can be correlated quickly with the patient's signs and symptoms, and, most importantly, does not employ ionizing radiation. MRI is occasion...

Transrectal ultrasound

Transrectal ultrasound (TRUS) is a technique that is used most commonly to evaluate the prostate gland, including ultrasound-guided prostate biopsies depth of invasion of colon/rectal cancer (for staging purposes) It can also be used for guidance in placing a transrectal drain, or in rare pro...


Urethrography refers to the radiographic study of the urethra using iodinated contrast media and is generally carried out in males. Terminology When the urethra is studied with instillation of contrast into the distal/anterior urethra it has been referred to as: retrograde urethrography (RUG)...

Urinary tract infection

Urinary tract infection (UTI) is a common clinical condition involving the bladder (cystitis) and kidneys (pyelonephritis). It is commonly divided into 'uncomplicated' and 'complicated' infections.  Clinical presentation painful urination strangury bloody, dark, cloudy urine urinary frequen...

Voiding cystourethrography

Voiding cystourethrography (VCUG), also known as a micturating cystourethrography (MCU),  is a fluoroscopic study of the lower urinary tract in which contrast is introduced into the bladder via a catheter. The purpose of the examination is to assess the bladder, urethra, postoperative anatomy an...

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