Trabeculectomy For Glaucoma Following Centraflow Implantable Collamer Lens With High Lens Vault.

Purpose: To report a case of unilateral secondary angle closure glaucoma post phakic intraocular collamer lens (ICL) placement in both eyes, managed with trabeculectomy.

A 27year male patient underwent both eyes ICL surgery two years ago for asymmetric myopia developed glaucoma in the right eye (RE) that had higher myopia. He presented with an IOP of 36mmHg not controlled on maximum tolerable medications in his RE. He had occludable angles with ICL vault of 756 microns in the RE with advanced glaucomatous field defect. The case was managed with trabeculectomy without ICL explanation. Postoperative IOP at 6-month follow-up was 16mmHg with a stable ICL vault.

A 27-year-old male underwent both eyes uncomplicated ICL implantation, toric in the right eye and plano in the left eye (Visian ICL, Staar inc., Monrovia, CA) for myopia 2 years back. He presented with a blurred vision and pain in the right eye (RE) for 2 months. His pre-ICL refraction was -13 Diopter sphere with -2 Dioptre cylinder at 180 degree in RE and -4 Diopter sphere in left eye (LE).  RE visual acuity was 3/60 improving to 6/18 with refractive correction of -1.75DS and IOP was 36mmHg on maximum topical glaucoma medications and oral acetazolamide. Slit lamp examination showed uniformly shallow anterior chamber of von Herrick grade 1 and a total glaucomatous optic neuropathy. On gonioscopy, the angle of RE was occludable but upon manipulation, a normally pigmented trabecular meshwork and scleral spur was seen. His LE had a vision of 6/6 and IOP of 14mmHg, a normal anterior chamber depth, angle was open and normal on gonioscopy. The ICL vault was 756 microns in RE and 540 microns in LE. The visual field showed an advanced visual field loss with a biarcuate scotoma in the RE and a normal field in LE. He was planned for trabeculectomy with ICL in situ. His IOP was 14mm on post op day 1 and  stabilised to 16mmHg till his follow up 6 month post operatively. No change in his anterior chamber depth or ICL lens vault was seen and best corrected visual acuity remained same as pre-operative i.e 6/18 with -1.75DS without any astigmatic error.

: A pseudophaco-phacomorphic mechanism of secondary angle

closure glaucoma caused by a high ICL lens vault was the probable mechanism of glaucoma in the patient that was managed successfully with Trabeculectomy alone.

This case highlights the efficacy of trabeculectomy in post ICL glaucoma with high lens vault and shallow anterior chamber without compromising the results of the refractive surgery. Though long-term studies of more number of cases are required to study efficacy of trabeculectomy in such scenarios, the rarity of this complication, might preclude such studies.