IMAGES IN CLINICAL UROLOGY
PERINEAL MEDIAN RAPHE CANAL: A TYPICAL IMAGE P. RAVASSE, T. PETIT,
AND
C. JEANNE PASQUIER
A
4-year-old boy presented at our institution with an anomaly of the perineal median raphe. It was a long and narrow tumefaction developed strictly on the midline on the median raphe between the scrotum and anus. The lesion extended 4 cm and was unilocular (Fig. 1), although cyst enlargement was present at either extremity. Pressure at one extremity was transmitted to the other, reflecting a liquid subcutaneous collection. No inflammatory signs were found. Because of the recent development, total surgical excision was performed with no recurrence. The pathologic examination demonstrated urinary epithelium lining the cyst (Fig. 2). COMMENT Median raphe cysts are rare lesions but are perhaps underevaluated because they can remain asymptomatic. They are always located on the midline between the urethral meatus and the anus. They are more common on the glans and penile skin. The lesion can be cystic, but sometimes it looks like an elongated structure called a raphe canal, such as we observed in our case. These congenital anomalies are reported equally in the pediatric population and in adults. They are usually asymptomatic, but some cases have reportedly been detected after infection. Histologically, two types of epithelium can be seen lining the cyst: a pseudostratified columnar epithelium as the urothelium1 or a squamous stratified epithelium.2 Those epithelia are sometimes associated in the same cyst.3 They never communicate with the urethra. The embryogenesis is not clear, and several theories have been proposed. One is the development of embryologic remnants after the fusion of the urethral folds,4 another is the abnormal development of the paraurethral ducts.1 Surgical excision followed by primary closure is indicated in symptomatic cases. Expectant treatment can be suggested in small asymptomatic lesions.5 From the Departments of Pediatric Surgery and Pathology, Caen University Hospital, Caen, France Reprint requests: Philippe Ravasse, M.D., Chirurgie Pediatrique, C.H.U. Cote de Nacre, Caen 14033 Cedex, France Submitted: July 2, 2001, accepted (with revisions): September 24, 2001
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FIGURE 1. Under general anesthesia, just before the surgical excision, probing the canal with a large nylon suture demonstrated a unilocular lesion with some enlargement at either extremity.
FIGURE 2. Histologic examination revealed in some places (arrow) the cyst lined by a urothelium.
REFEENCES 1. Cole LA, and Helwig EB: Mucoid cysts of the penile skin. Urology 115: 397–399, 1976. 2. Lanasa JA: Epidermal cyst of the median raphe. Urology 8: 401– 402, 1976. 3. Claudy AL, Dutoit M, and Boucheron S: Epidermal and urethroid penile cyst. Acta Dermatol Venereol 71: 61– 62, 1991. 4. Asarch RG, Golitz LE, Sausker WF, et al: Median raphe cyst of the penis. Arch Dermatol 115: 1084 –1086, 1979. 5. Little JS, Keating MA, and Rink RC: Median raphe cysts of the genitalia. J Urol 148: 1872–1873, 1992. UROLOGY 59: 136, 2002
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0090-4295/02/$22.00 PII S0090-4295(01)01520-5