Ophthalmology Grand Rounds (Iowa)

Question 1

List 3 risk factors for cortical cataract development

Answer 1

1. Sun Exposure
2. Female Gender
3. Dark Irides

Question 2

What causes a Morgagian Cataract?

Answer 2

Occurs when cortical cataracts become hypermature. As the periphery of the lens opacifies, lens fibers degenerate leaving protein globules between the cortical lamellae. The globules begin to coalesce forming large accumulations of liquified proteins. When the majority of the cortex is affected, the lens nucleus is left floating in the liquified cortex forming a Morgagnian cataract.

Question 3

What is phacolytic glaucoma?

Answer 3

Because of the increased concentration of lens proteins in mature and hypermature cataracts, water is drawn from the aqueous into the lens cortex via osmosis. This creates a swollen, tense lens capsule. Lens proteins may leak from tiny vents in the capsule. These proteins trigger a non-granulomatous inflammatory reaction. Machrophages collect in the anterior chamber and phagocytize the lens protein. Both protein-laden machrophages and lens protein collect in the TM thus clogging aqueous outflow and increasing IOP.

Question 4

What is phacoantigenic endophthalmitis?

Answer 4

With the increased tension of the lens capsule due to a mature or hypermature cataract, spontaneous rupture or rupture after mild trauma will cause leakage of lens nucleus fragments or cortical material into the AC. This causes a severe granulomatous inflammatory reaction.

Question 5

Name several differentials for ectopia lentis

Answer 5

1. Marfan Syndrome: AD connective tissue disorder that affects the musculoskeletal, cardiovascular and ocular systems.
2. Homocystinuria: AR inherited disorder that affects the metabolism of the AA methionine. Joints tend to be “tight” (unlike Marfan’s)
3. Sulfite Oxidase Deficiency: Inherited inability to metabolism sulfated AA. Infants typically will present with intractable seizures, abnormal tone and mental retardation.
4. Weill-Marchesani Syndrome: Genetic disorder of connective tissue. Patients are typically short in stature, have joint stiffness, eye problems, short - broad head.
5. Hyperlysinemia: AR metabolic disorder that causes lysine accumulation in the blood.