Acute angle closure with cataract: lens extraction or laser first?
A 66-year-old hypermetropic woman presents to the emergency eye clinic with a 3-day history of a painful red right eye, nausea and blurred vision. Right eye: visual acuity 6/60, IOP 58 mmHg by Goldmann, diffuse microcystic corneal oedema, fixed mid-dilated pupil, shallow anterior chamber. She is started on intravenous acetazolamide 500 mg, topical timolol/dorzolamide, pilocarpine 2% and topical steroid. Forty-eight hours later the right eye is comfortable, the cornea is clear, IOP is 14 mmHg on timolol/dorzolamide and visual acuity is 6/12. Gonioscopy shows 360-degree appositional closure with 4 clock hours of peripheral anterior synechiae; the lens shows nuclear sclerosis grade 2. Left eye: IOP 18 mmHg, Shaffer grade 1-2, clear lens, axial length 22.0 mm, anterior chamber depth 2.05 mm. She is otherwise well, on amlodipine, and lives alone 40 minutes from the clinic.
1. What is your definitive management for the right eye, and what factors would make you choose lens extraction over laser peripheral iridotomy?
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Definitive management: phacoemulsification and IOL, not LPI alone.
Reasoning:
- The mechanism is lens-driven: axial length 22.0 mm, anterior chamber depth 2.05 mm, a grade 2 cataract and 4 clock hours of peripheral anterior synechiae. LPI relieves pupillary block but does not deepen the angle fully, and leaves the cataract to be dealt with later.
- The EAGLE trial showed that lens extraction gave better IOP control and fewer subsequent angle-closure attacks than LPI in eyes with angle closure and cataract, with similar safety.
- She is 66 and will need cataract surgery anyway; combining the two avoids a second intraocular procedure.
When I would still choose LPI first:
- If she could not tolerate surgery or anaesthesia, had a very limited life expectancy, or had such advanced glaucomatous damage that any intraocular surgery risk was unacceptable.
- If there were more than 180 degrees of synechiae and advanced cupping, I would consider combined phaco-trabeculectomy rather than phaco alone.
- LPI remains a reasonable temporising measure if surgery cannot be arranged within a few weeks, and should be considered for the fellow eye if lens extraction is not planned.
2. How would you manage the left eye, and what is the evidence base for your choice?
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Left eye: offer prophylactic LPI, with a low threshold for surgery.
- The left eye is at risk: anterior chamber depth 2.05 mm and Shaffer grade 1-2. However, evidence that prophylactic LPI prevents acute attacks in fellow eyes is modest: it reduces the rate of acute angle closure but many patients still progress to needing cataract surgery, and the angle may remain narrow.
- Because the right eye is going to have lens extraction and she lives alone far from the clinic, an acute attack in the left eye would be dangerous. I would offer LPI now and counsel that it does not remove the need for cataract surgery.
- An alternative is to bring her back for left phaco in 3-6 months and observe in the interim with a written safety-net plan. This is reasonable if she prefers a single operation.
- Either way: document IOP and gonioscopy, give written advice about acute symptoms, and ensure she can access care quickly.
3. If she were 88, frail, with advanced right disc cupping (CDR 0.9 and a field defect to 10 degrees), how would your plan change?
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Priorities shift from definitive angle cure to protecting the small remaining field and minimising surgical risk.
- LPI plus maximal tolerated topical therapy may be safer than a long general anaesthetic; but if the cataract is visually significant, phaco alone can lower IOP by 3-5 mmHg.
- If the target IOP cannot be met medically, combined phaco-trabeculectomy with mitomycin C is an option, accepting the higher risk of hypotony and endophthalmitis in a frail patient.
- I would involve her family, obtain an anaesthetic assessment, and set a realistic target IOP (for example low teens) with a clear ceiling of intervention agreed in advance.
- The fellow eye still needs protection, but the same frailty considerations apply.