Contributor: Gordon K. Klintworth
A Morgagnian cataract (hypermature cataract) is a specific type of cortical cataract [cataract - cortical] and a more advanced stage of a mature cataract [cataract - mature]. It is a one in which the entire lens cortex has become liquefied and the sclerotic lens nucleus sinks by gravity to the bottom of the lens.The degenerated lens material within a mature cataract exerts an osmotic pressure, causing the damaged lens to increase in volume by imbibing water. Such a swollen lens may cause phakomorphic glaucoma [glaucoma - phakomorphic]. After swelling the cataractous lens gradually becomes smaller than normal and irregular in thickness and its previously smooth capsule wrinkles. This decrease in lens size presumably results from the escape of small particles from the liquid cortical cataract through an intact lens capsule to enter the surrounding aqueous. Here it becomes engulfed by macrophages often leading to phakolytic glaucoma [glaucoma - phakolytic]. Morgagnian globules are present between the degenerated cortical lens fibers of a Morgagnian cataract. Rarely the lens capsule of a Morgagnian cataract lens ruptures spontaneously to extrude cataractous material into the aqueous. If this happens, or if an extracapsular cataract extraction is performed the entire contents of the lens may escape to leaving a clear lens capsule bag.