A longitudinal vaginal septum is a congenital abnormality of the vagina where a septum divides it into two parallel cavities.
Usually asymptomatic unless obstructed and if obstructed it may cause cyclic pelvic pain. Amenorrhea may occur if both cavities are obstructed .
It is due to failure of lateral fusion / reabsorption of the paired Mullerian ducts during development of the vagina.
It may be difficult to diagnose in the absence of obstruction.
T2 weighted images demonstrate hypointense septum (relative to the hyperintense secretions/blood) with two hemivaginas present .