Glaucoma

An earlier review favorably compared Latanoprost to Timolol for six months. This study shows Latanoprost to be effective for one year in all races when applied once per day for ocular hypertensiona nd open angle glaucoma. IOP was reduced 30-35% on average, correlating to a pretreatment IOP of 25 and treament pressure of 17.

Side effects noted:

1. increased iris pigmentation (5%) - possibly as high as 15% though...
2. other ocular problems (3%) - 1% allergic/toxic, rest unrelated
3. inadequate control (1%)

Latanoprost is a prodrug of PGF 2alpha, a prostaglandin. It is thought to act by increasing uveal scleral outflow. Recommended dosing is once a day in the evening.

Raymond Magauran, MD
West Bloomfield, MI

Glaucoma

The scanning laser ophthalmoscope is coming of age. The authors compared optic nerve head topography results in normal, primary open angle glaucoma (POAG) and ocular hypertensive (OHT) patients. They showed for normals, to OHT patients to POAG patients:

1. Cup area and volume increases
2. Rim area and volume decreases
3. Cup/disc area ratio increases

As the authors acknowledge, a longitudinal study needs to be performed to see if the scanning laser ophthalmoscope can detect progression from one diagnosis to the other. If so, this may become the earliest method to accurately detect progression.

Raymond Magauran, MD
West Bloomfield, MI

Glaucoma

The authors identified 91 patients with optic disc hemorrhages by reviewing the records of 10,914 patients with glaucoma or ocular hypertension at the Massachusetts Eye and Ear Infirmary. The records included 33,660 disc photographs. Extensive comparisons were made with a control group.

Their findings:

1. Frequency of disc hemorrhage in the glaucoma population was 0.8%.
2. 63% of eyes with hemorrhage had a visual field decrease compared to 24% of control eyes.
3. 84% of hemorrhages occur in the temporal quadrant.
   Most common location - inferotemporal (48% of total)
   Optic disc changes were significantly more likely to occur with temporal hemorrhages.
   Intraocular pressure was significantly lower with temporal hemorrhages - Is the temporal optic nerve more sensitive to damage?
4. Primary open angle glaucoma eyes with hemorrhage underwent significantly more surgery and/or laser than controls.
5. When glaucoma progression was noted after a hemorrhage, the visual field decreased BEFORE the optic disc changed (16.8 vs. 23.8 months).
6. Recurrent disc hemorrhages did not increase the rate of disc change or visual field decrease.

Raymond G. Magauran, M.D.
Kresge Eye Institute,
Detroit, MI