GLAUCOMA GRAND ROUNDS

When Advanced Glaucoma Warrants Surgery

by J. James Thimons, O.D.

A 72-year-old black male came to us for a second opinion and consult on his bilateral glaucoma. The patient demonstrated multiple systemic complaints, most notably hypertension and Type II diabetes, for which he was taking Procardia (nifedipine) and glyburide, respectively. He was also taking Timoptic-XE (timolol maleate) once daily and Trusopt (dorzolamide) BID, both O.U. The patient complained of moderate itching bilaterally over the last four to six weeks with some conjunctival redness. His family's history was positive for glaucoma and cataracts.

Exam Findings.
Visual acuity was 20/25- O.D., 20/25+ O.S. Pupillary testing showed 3/3/2+/-mg. Extra-ocular motility assessment was within limits, but confrontation fields showed diminished response superiorly in both eyes. Both corneas had mild striae and moderate guttata; the anterior chambers were deep and quiet. There were 1+ nuclear scleroses in each eye, and the anterior vitreous had moderate syneresis.

IOPs were 18mm Hg O.D., 26mm Hg O.S. at 10 a.m. Goni-oscopy demonstrated trabecular meshwork to ciliary body 360 degrees with minimal pigmentation. Bilateral fundus examination re-vealed significant cupping to approximately 0.9 in each eye with inferior temporal erosion of the neuroretinal rim. Visual field testing demonstrated dense losses in both superior hemifields.

This patient's ophthalmic presentation of elevated IOP, optic nerve damage and visual field loss all place him in an advanced stage of glaucoma. With his family history and racial predisposition to the disease, he is at extreme risk for further loss of visual field and vision.

Treatment.
 I set a goal intraocular pressure of 16mm Hg or less. Because of the itching, corneal striae and the somewhat compromised endothelium, I discontinued the Trusopt in the right eye as a trial. Two weeks later, the symptoms in that eye subsided, and the patient's IOP had not changed. I then discontinued Trusopt in the left eye and added Xalatan (latanoprost) as a trial. Two weeks later, the patient's IOPs were 19mm Hg O.D., 21mm Hg O.S. Given the positive result of the Xalatan in the left eye, I prescribed it every day for both eyes.

A month later the patient's IOPs were 16mm Hg O.D., 21mm Hg O.S. Because of the risk of visual disease progression, I thought that a pressure of 21mm Hg was too high. I subsequently added Alphagan (brimonidine) BID in the left eye and asked him to return in six weeks.

At six weeks, the patient's IOPs were 16mm Hg O.D., 17mm Hg O.S. at 1 p.m. The patient complained of facial swelling over the past 7-10 days, accompanied by mild itching in his left eye. There was a mild chemosis of the conjunctiva in the left eye. Due to the time frame involved in the onset of these symptoms, I concluded the Alpha-gan was causing an allergic reaction and discontinued it. During a follow-up phone call with the patient a week later, he reported a remarkable improvement in symptoms.

Two weeks later the patient returned. IOPs had increased to 17mm Hg O.D., 22mm Hg O.S. on the Timoptic and Xalatan. Because we weren't able to achieve the goal pressure with topical drugs, I recommended argon laser trabeculoplasty to the left eye. The patient agreed, was referred and underwent an uncomplicated ALT.

At his one-week post-op visit, the IOPs had decreased to 16mm Hg O.D., 19mm Hg O.S. at 11 a.m. I tapered his steroid therapy and asked him to return in a month for continued evaluation. At the one-month visit, his IOPs were 17mm Hg O.D., 16mm Hg O.S. I maintained the current therapy and have seen him regularly over the past 15 months. His pressures have stayed within the 15-18mm Hg level, and his visual fields have remained stable.

Discussion.
This case demonstrates a typical scenario in advanced glaucoma management because it requires a significant investment of clinical time and decision-making to develop the right treatment plan.

This patient's allergic reaction to two different glaucoma medications creates challenges both diagnostically and therapeutically. Further, the advanced optic nerve and visual field damage requires that his pressures be reduced significantly, which medical therapy alone cannot always achieve.

A patient with this type of clinical presentation needs frequent monitoring of no fewer than four to six times a year, depending on IOP control. Further, if the patient demonstrates progressive field loss and optic nerve head damage, or if IOPs increase, consider argon laser trabeculoplasty. If that's not a viable option, or if it's unsuccessful, the next step would be to consider trabeculectomy to preserve vision.