Acute angle closure in a patient who cannot attend frequent follow-up
A 58-year-old woman presents to a district hospital emergency department with a two-day history of a painful red right eye, vomiting and blurred vision. Corrected acuity is counting fingers in the right eye and 6/9 in the left. Right intraocular pressure is 52 mmHg, with a hazy cornea, a fixed 5 mm pupil and a shallow anterior chamber; the fundus cannot be seen. The left eye has 6/9 acuity, intraocular pressure of 18 mmHg on no treatment and a very shallow peripheral chamber. She is started on topical timolol, pilocarpine and dexamethasone, oral acetazolamide and intravenous mannitol. After 36 hours the right cornea has cleared, the intraocular pressure is 34 mmHg, gonioscopy shows 360 degrees of appositional closure with no peripheral anterior synechiae, and the lens shows moderate nuclear sclerosis. She lives three hours from the nearest glaucoma unit and cannot attend frequent follow-up visits.
1. How do you interpret the gonioscopic findings, and how do they influence your choice between laser peripheral iridotomy, clear lens extraction and trabeculectomy in this right eye?
Read the worked answer
The key gonioscopic point is that the closure is appositional with no peripheral anterior synechiae. The angle is being closed by iris–lens apposition (pupillary block plus a thick, anteriorly positioned lens), not by fixed fibrous synechiae. That matters for two reasons: the closure is potentially reversible, and the dominant mechanism is the lens rather than a permanently damaged outflow system. It also means the eye has not yet entered the chronic synechial stage where drainage failure is largely irreversible.
Weighing the options:
- Laser peripheral iridotomy relieves pupillary block, but with a moderate cataract, a thick lens and a pressure still 34 mmHg after 36 hours of maximal medical therapy, it is unlikely to control pressure on its own and commits her to a second intraocular operation later.
- Clear lens extraction addresses the mechanism directly. In primary angle-closure disease with pressure at or above 30 mmHg, randomised evidence (EAGLE) showed phacoemulsification gave better pressure control and quality of life than iridotomy, with fewer subsequent operations. She already has a visually significant cataract, and one operation is far more realistic than a laser plus later surgery given her travel distance.
- Trabeculectomy is the wrong first move in an eye that is still inflamed after an acute attack: the conjunctiva should be preserved for the future, and filtration surgery on an inflamed eye has a high failure rate.
My plan is phacoemulsification with intraocular lens implantation under cover of continued pressure-lowering treatment, with a planned review of pressure and angle at 6 weeks. If surgery were unavailable within weeks, I would perform an iridotomy as a temporising measure.
2. What is your management of the asymptomatic left eye, and how would you counsel her about adherence and follow-up given that she lives three hours away?
Read the worked answer
The left eye is the more instructive problem: a shallow peripheral chamber with a pressure of 18 mmHg is a fellow eye at high risk of acute angle closure, and the risk is highest in the first weeks after an attack in the other eye. Gonioscopy of the left eye should be documented and, in a patient with this anatomy and this distance from care, I would perform prophylactic laser peripheral iridotomy there rather than observe. It is a one-off, low-risk procedure that can be done at the same visit as her right eye assessment and reduces the chance of a second emergency she cannot easily reach.
Counseling should be concrete, not generic:
- Explain that the left eye has the same crowded anatomy and can occlude without warning, and that the iridotomy is prevention, not treatment of a current problem.
- Give written instruction on warning symptoms (pain, haloes, nausea, sudden blur) and a named contact number, because recognising an attack early is her main protection given travel time.
- Be realistic about drops: complex regimens fail in patients far from care. Prefer once- or twice-daily fixed combinations, check she can instil them, and involve a family member.
- Schedule follow-up around her realities - a single combined visit after right eye surgery, with a local optometrist or physician checking pressure in between if possible.
- Confirm that surgery on the right eye also substantially lowers her future risk on that side, so the plan is definitive rather than a holding measure.
If she declined surgery, I would document the discussion and arrange an iridotomy in both eyes as the minimum safe package.