Case One
Shallow Anterior Chamber After Laser Iridotomy

Patient history/presentation: A 79-year-old Caucasian female presented with a 2-day history of pain OS. The past ocular history was remarkable for primary open-angle glaucoma and age-related macular degeneration (AMD) OU. Past medical history was significant for congestive heart failure and mitral valve replacement.

She was taking Betoptic S b.i.d. OU, Alphagan b.i.d. OU, Pilocar (2%) q.i.d. OU for glaucoma, and Lasix and Coumadin for her cardiac condition.

Examination/initial diagnosis and treatment: Visual acuity was 20/200 OS; the anterior chamber was shallow; and the IOP was 29 mmHg OS. Dilation was deferred, and examination of the posterior pole was limited. A laser iridotomy OS was performed for presumed acute angle-closure glaucoma. Two days later, the patient complained of increasing pain and worsening vision OS. On exam she was again found to have a shallow anterior chamber and an IOP of 42 mmHg OS. She was then referred to a tertiary glaucoma center for evaluation.

Her vision was 20/70 OD and hand motion OS. Applanation tensions were 14 mmHg OD and 48 mmHg OS. Anterior segment examination was notable for a deep anterior chamber OD and a shallow anterior chamber OS despite a patent peripheral iridotomy. There were mild nuclear sclerotic cataracts OU.

Gonioscopy revealed an angle open to the ciliary body OD, and completely closed without visible angle structures OS. Funduscopic exam showed drusen and patchy chorioretinal atrophy in the macula OD. Dilation OS revealed an extensive choroidal hemorrhage confirmed on B-scan ultrasound. (See image on previous page.) Blood testing revealed an INR of 4.0, which is slightly above therapeutic range.

Due to the patient's coagulation status, she had experienced spontaneous choroidal hemorrhage from a pre-existing neovascular membrane. Fluorescein angiogram performed 2.5 years prior was read as "probable occult choroidal neovascular membrane OS." The retinal surgeon opted to defer laser treatment, as he felt it would not improve vision. The choroidal bleeding produced secondary angle-closure glaucoma via a "posterior pushing" mechanism. We suspect that the choroidal hemorrhage produced the shallow chamber, which prompted the performance of the LPI initially.

Management: The patient was admitted to the hospital for maximum anti-glaucoma treatment and for pain control with narcotics. Treatment did not lower her IOP or relieve her pain. A retinal consult indicated that the patient was not a surgical candidate due to a poor visual prognosis and high risk of re-bleeding. Over the next few days the patient's pain escalated, and visual acuity OS deteriorated to NLP. The patient's cardiologist felt that the patient was not medically stable for enucleation. In order to achieve pain control, the patient received fresh frozen plasma to lower her INR, then had a retrobulbar injection of 2 cc of 2% lidocaine, and 1 cc of 25 mg of chlorpromazine. She experienced immediate relief of pain. Because pain relief was sustained for the following day, she was discharged from the hospital.

At her last visit 3 weeks following the retrobulbar chlorpromazine injection, she reported no pain. Her vision was NLP OS, and IOP was 42 mmHg OS. She still had a shallow anterior chamber, a diffusely hazy cornea, and a small hyphema.

Discussion: The differential diagnosis of persistent shallow anterior chamber after laser peripheral iridotomy (LPI) includes either an LPI that is not patent or an LPI that is patent but not functional due to surrounding irido-lenticular adhesion, residual phacomorphic glaucoma, or plateau iris syndrome. The diagnosis of primary angle-closure glaucoma should be questioned if the fellow filtration angle is not shallow. Asymmetry of the anterior chamber depths should suggest a secondary angle-closure glaucoma mechanism.

Angle-closure glaucoma due to choroidal hemorrhage from a choroidal neovascular membrane has a poor visual prognosis. [Alexandrakis G, Chaudhry NA, Liggett PE, et al. Spontaneous suprachoroidal hemorrhage in age-related macular degeneration presenting as angle-closure glaucoma Retina 1998;18(5):485-6]

Treatment objectives may focus on control of pain rather than salvage of vision. If examination of the other eye with fluoroscein angiography reveals wet AMD, one must consider possible focal laser ablation of the neovascular membrane versus a discussion with the internist to maintain a lower INR.

In this clinical scenario, retrobulbar injection of chlorpromazine was a safe and effective option for achieving pain control. [Chen TC, Yeun SJA, Sangalang MA, et al. Retrobulbar Chlorpromazine injections for the management of blind and seeing painful eyes. J Glau 2002;11:209-213]

Case One was submitted by Louis R. Pasquale, M.D., with the assistance of Usha R. Pinninti and Teresa C. Chen, M.D., from the Massachusetts Eye and Ear Infirmary in Boston. If you would like to comment on this case, e-mail Ophthalmology Management at ifftda@boucher1.com.

Case Two
Lowering Extremely High IOP Without Surgery

Patient history/presentation: A 48-year-old black woman with a 2-month history of blurred vision in the right eye presented for evaluation. Her medical history demonstrated hypertension, for which she was taking Norvasc and Dyazide. Her father had a history of glaucoma.

Examination/findings: Her best-corrected visual acuity was 20/25 in her right eye and 20/20 in her left eye. Her angles were open with mild pigmentation of the trabecular meshwork. Bilateral slit-lamp examination was unremarkable. Her IOPs by applanation tonometry were 57 mmHg in the right eye and 28 mmHg in the left eye at 9:45 a.m. She had a relative afferent papillary defect on the right eye. Her retinal exam was normal bilaterally.

The patient's optic nerves demonstrated marked glaucomatous cupping with loss of inferior neural rim in the right eye. She had an overall c/d ratio of 0.85. In the left eye, she had a small and tilted disc. It was healthier than the right eye in that the rim was preserved in all four quadrants. The overall c/d ratio was 0.40.

Visual-field testing correlated to her glaucomatous cupping. She had an inferior defect and a superior arcuate defect extending nasally and centrally in the right eye. The left eye revealed mild nasal and inferior changes.

Optic nerve images showed marked cupping in both eyes. Above: The left disc was smaller and tilted, but healthier than the right disc, as the rim was preserved in all four quadrants.

Treatment: The patient was advised that vision would be difficult to maintain in her right eye over her lifetime given the extent of damage and her relatively young age. She would need an extremely low IOP in the right eye, and was told that surgery might be the only way to achieve that goal.

A very low target pressure was set for the right eye. Based on results of the Advanced Glaucoma Intervention Study and Shirakashi, et al., which demonstrated essentially a halting of progression of glaucomatous cupping in cases of advanced glaucoma when IOPs of 14 mmHg or less are obtained, target for the right eye was set to 14 mmHg or lower.

The patient's left eye was in better condition. In accordance with recommendations from the Preferred Practice Pattern and results from L Mao, et al., demonstrating stability of glaucomatous cupping with IOP in the upper teens in early glaucoma, her left-eye target pressure was set to the upper teens.

Medical therapy was to be given a brief attempt on the right eye. The patient was administered Lumigan in both eyes while in the office. Within 1 hour, her IOP in the right eye had fallen to the 20s. At 1 week, her IOP was 19 mmHg OD and 17 mmHg OS. At another 1 month, her IOPs remained 19 mmHg in the right eye and 17 mmHg in the left.

Alphagan P was added to the right eye, bringing that IOP down to 13 mmHg 1 month later.

Discussion: With modern medication, surgery may be avoided or delayed in cases previously considered to be only amenable to surgery. In addition, we can attain maximal pressure reduction with minimal medical therapy.

Case Two was submitted by Thomas Bournias, M.D., an attending physician in the department of ophthalmology at Northwestern University Medical School in Chicago. If you would like to comment on this case, e-mail Ophthalmology Management at ifftda@boucher1.com.