Imperforate hymen is a congenital condition in which the hymen is without a normal central opening.
0.1% of patients, usually isolated findings
Primary amenorrhea with cyclic lower abdominal pain during menarche age. 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 sino-vaginal bulb. Imperforate hymen occurs due to a failure of recanalization of this membranous vestige.
Usual initial imaging modality of diagnosis
- distended fluid-filled vagina (hematocolpos) and uterus (hematometra) with internal echoes
Signal changes follow subcute bleeding episodes and the blood products in hematocolpometra:
- 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