We read with interest the report by Drs Doyle and Smith1
on the effect of phacoemulsification on hypotony following trabeculectomy.
They are to be congratulated on their positive outcomes in 9 eyes with an
intraocular pressure (IOP) of 6 mm Hg or lower prior to phacoemulsification.
In 1998, we investigated the outcome of cataract extraction on trabeculectomy
function in 115 eyes,2 including 19 with
hypotony (which we also defined as having an IOP ≤ 6 mm Hg) before cataract
surgery. Antifibrosis agents had been used during trabeculectomy in most of
these eyes, including mitomycin C in 13 eyes and 5-fluorouracil in 3 eyes.
Thirteen eyes subsequently underwent phacoemulsification, and 6 had extracapsular
cataract extraction. Our IOP findings after cataract extraction were similar
to those of Doyle and Smith, with the mean IOP increasing significantly from
4.6 to 7.5 mm Hg (P = .002; paired 2-tailed t test), but 11 (58%) of 19 eyes did not have a final IOP
higher than 6 mm Hg after a mean follow-up of 17 months. However, our treatment
did not include the use of retained viscoelastic at case conclusion or routine
minimization of postoperative anti-inflammatory medications. Two patients
required short-term use of glaucoma medications, and 2 eyes underwent bleb
needling (both within 1 month of cataract surgery). Visual acuity was improved
by at least 2 lines in 18 (95%) of 19 patients, but 3 eyes required trabeculectomy
revision for persistent hypotony. The methods of Doyle and Smith1
seem to result in better overall outcomes, although most of their patients
had undergone previous interventions (eg, autologous blood injection with
bandage contact lens placement in 6 eyes, and drainage of choroidal effusions
with intraocular viscoelastic placement in 1 eye) that might have contributed
to the postoperative course noted after phacoemulsification.
Chen PP, Budenz DL, Parrish RK. Cataract Extraction and Hypotony After Trabeculectomy. Arch Ophthalmol. 2001;119(5):783. doi: