Imperforate hymen is a congenital condition in which the hymen lacks a normal opening.
It happens in 0.1% of the female population, usually an isolated finding.
Primary amenorrhea with cyclic lower abdominal pain during menarche age. An imperforate hymen can be diagnosed at physical examination upon identification of a bulging, bluish membrane that allows positive transillumination at the introitus; consequently, imaging is rarely indicated.
Failure of the recanalization process of the distal end of the vagina. The hymen indicates the junction between the urogenital sinus and sinovaginal bulb. Imperforate hymen occurs due to a failure of recanalization of this membranous vestige.
Usual initial imaging modality of diagnosis, it shows:
- distended fluid-filled vagina (haematocolpos) and uterus (haematometra) with internal echoes representing haemorrhage of various ages
Signal changes follow subacute bleeding episodes and the blood products in haematometrocolpos:
- T1: hyperintense endometrial fluid extending down to the level of the hymen
- T2: hypointense endometrial fluid extending down to the level of the hymen
- 1. Walker DK, Salibian RA, Salibian AD et-al. Overlooked diseases of the vagina: a directed anatomic-pathologic approach for imaging assessment. Radiographics. 2011;31 (6): 1583-98. doi:10.1148/rg.316115531 - Pubmed citation
- 2. Radiology Review Manual. Lippincott Williams & Wilkins. (2011) ISBN:1451153643. Read it at Google Books - Find it at Amazon