Pre-operative assessment of bladder endometriosis

The aim of our study was to verify the reliability of transvaginal ultrasonography in the pre-operative evaluation of bladder endometriosis. Six patients with suspected bladder endometriosis were studied. At referral to our department all six women underwent magnetic resonance imaging (MRI), transabdominal and transvaginal ultrasonography, cystoscopy and descending urography. Subsequently all the women underwent transperitoneal cystotomy and excision of endometriotic lesion at laparotomy. In three patients the bladder endometriotic lesions were continuous with adenomyosis in the anterior uterine wall. Histological examination confirmed the endometriotic nature of bladder nodule in all cases. Abdominal ultrasonography visualized the detrusor neoformation in all the patients but was less precise than transvaginal ultrasonography and MRI in defining the size of the lesions, infiltration of the detrusor and continuity with extravesical lesions. Transvaginal ultrasonography was more accurate and versatile than abdominal ultrasonography. The better image resolution allowed an accurate structural analysis of the bladder wall lesion. Furthermore, involvement of the uterovesical septum could be evaluated and adjacent myometrial infiltration recognized. MRI, although very precise, was less versatile than transvaginal ultrasonography and less accurate in establishing the margins of the lesions as perilesional fibrosis is visualized less clearly than areas containing haematic material. Urography was aspecific but still useful to evaluate the integrity of the upper urinary tract and ureters. In conclusion, in our patients transvaginal ultrasonography was found to be the most accurate technique in the diagnosis of bladder endometriosis.