Extravasation of urine
Extravasation of urine refers to the condition where an interruption of the urethra leads to a collection of urine in other cavities, such as the scrotum or the penis in males. It can be associated with a calculus.Mechanism
An injury to the urethra leaving Buck's fascia intact results in a collection of urine limited to the penis, deep to Buck's fascia. However, if the injury to the bulb of the penis results in urethral injury accompanying a tear of the Buck's fascia, then extravasated blood and urine would accumulate in the superficial perineal space, passing into the penis as well as the scrotum and lower anterior abdominal wall. Extravasation of urine involving a compromised Buck's fascia can be appreciated clinically by blood collecting in the superficial pouch, resulting in a 'butterfly'-shaped region around the penis.Other
Extravasation of urine due to blunt renal trauma or ureteral obstruction can lead to the formation of an urinoma.
