GLAUCOMA GRAND ROUNDS

Trauma at Age 5 Leads
To Elevated IOP at Age 75

by J. James Thimons, O.D.

A 75-year-old white male was referred for consultation following extreme elevation of intraocular pressure in both eyes. The patient was in no acute distress nor did he have any significant medical history. He hadn't had a physical check-up in 10 years, but reported no evidence of diabetes, hypertension or other systemic illness. Family medical and ocular histories were negative. He was taking no medications and denied any allergies.

The patient did describe an episode of trauma at age 5. At that time his sight decreased significantly in his left eye. He underwent no medical or surgical intervention.

Physical Examination
Visual acuity was 20/50 O.D. with correction, no light perception O.S. Gross evaluation of the patient's head and neck revealed a marked exotropia of the left eye accompanied by an obvious separation of the iris from its root. Pupillary examination showed 4/3/2+ O.D., no response O.S., and a reverse Marcus Gunn sign. Extraocular muscle function was full in the right eye. There was mild limitation in right gaze in the left eye. Confrontation testing was within limits O.D. There was no response in any quadrant O.S.

The slit lamp examination showed intact corneal tissue bilaterally, with no evidence of trauma. The anterior chamber was deep in the right eye but significantly more shallow in the left on van Herick's test. The left iris showed iridodialysis extending from 10-1 o'clock. A redundant roll of iris tissue located near the pupil margin corresponded to the separation of the iris at its root. The lens of the right eye showed a 3+-4+ nuclear sclerosis. The left eye demonstrated a totally diffuse cataract with no penetration of the slit beam beyond the area immediately posterior to the anterior lens capsule.

Applanation tensions were 52mm Hg O.D. and greater than 80mm Hg O.S. Gonioscopy showed significant angle recession: in the right eye between 3 and 8 o'clock and in the left from near the area of iridodialysis through approximately 9 o'clock. The fundus exam showed a cup-to-disc ratio of approximately 0.7-0.8 with a shallow cup and a very difficult interpretation due to the cataract in that eye. The cataract in the left eye blocked a view of the fundus. Visual field testing with the Humphrey Field Analyzer II system using a 24-2 SITA standard program showed a surprisingly normal response given the clinical presentation.

Discussion
This patient presented with a very unique type of glaucoma—trauma at an early age and subsequent late-onset development of elevated intraocular pressure and other ocular problems.

Angle-recession glaucoma has a unique pathophysiology. The tearing of the ciliary body, which occurs at the time of the blunt trauma, grossly indicates the level of tissue damage. However, the microtrauma to the trabecular meshwork produces the fibrotic scarring that eventually compromises aqueous outflow.

Another interesting aspect of traumatic glaucoma is that the traumatic event frequently happens much earlier than the onset of the disease. Clinical studies and general observation attest that the time between the trauma and onset of disease can vary from a few weeks to several decades. In this case the apparent provoking trauma was a severe blow to the head and eyes when the patient was young. The finding that the pressure was slightly elevated in the good eye took place at another practitioner's office about eight years before our visit.

Treatment
After pulse (68) and blood pressure assessment (185/88), we began treatment very similar to that of a narrow-angle patient, but without cholinergic therapy. We started the patient on one drop of Betimol (timolol hemihydrate) and Alphagan (brimonidine) O.U. at 4 p.m.

We gave the patient additional doses of Alphagan Q30min over the next hour, and measured the pressure on the half hour. At the first measurement, IOPs were 52mm Hg O.D. and greater than 80mm Hg O.S. At the second measurement, IOPs were 46mm Hg and 78mm Hg. By the third measurement at 5:30 p.m., IOPs were 32mm Hg and 65mm Hg. Since his IOP decreased significantly over a two-hour period in the office, we sent him home on Betimol and Alphagan one drop BID O.U.

Unlike most angle-closure patients, individuals who present with extreme pressure elevation due to primary or secondary open angle glaucoma, and who haven't previously been treated with medical therapy, typically respond well to the initial application of topical medications. Rarely will you need to institute oral therapy. But if you must, use either Diamox (acetazolamide) 250mg Q30min for an hour or Neptazane (methazolamide) 50mg. In patients with angle recession, cholinergic drugs probably will have no significant effect because the damage to the trabecular meshwork largely precludes the IOP-lowering effect of pilocarpine.

At follow-up at 8:15 the next morning, this patient's pressures were 16mm Hg O.D. and 30mm Hg O.S. The slit lamp findings were the same and the patient's optic nerve showed relatively less cupping (about 0.6) than the day before. Cupping can decrease to a mild degree following reduction in pressure. This interesting phenomenon can occur in individuals whose IOP rises relatively quickly and whose optic nerve bows posteriorly as a result. This correlates with the patient's relatively normal visual field testing juxtaposed with extremely elevated IOP. Also, the appearance of the optic nerve the day before seemed inconsistent with the quality of the visual field.

Now that the eye is stable, future management aims toward visual rehabilitation with cataract extraction or possibly a combined procedure to aid in IOP control in the right eye. We will treat the left eye with ocular antihypertensives to prevent pain and provide comfort. There's no advantage to surgical intervention unless the lens becomes phacolytic and creates inflammation.