Phacoemulsification Changes Anterior Chamber Angle

Anterior chamber angle widening in eyes with primary angle-closure glaucoma was significantly greater after phacoemulsification than after phacotrabeculectomy for up to 6 months after surgery, according to the research published in the Journal of Glaucoma.

The investigators conducted a single-center, prospective, randomized clinical trial to compare anterior chamber angle following the 2 common surgeries, phacoemulsification and phacotrabeculectomy, for primary angle-closure glaucoma. 

Patients with concomitant primary angle-closure glaucoma and senile cataract, without a history of ocular surgery, trauma, or chronic miotic, were recruited for the study. Anterior segment optical coherence tomography was used to image the anterior segment and assess angle parameters (angle opening distance at 500 μm [AOD 500], trabecular iris surface area at 500 μm [TISA 500], and trabecular iris angle at 500 μm [TIA 500]) before surgery and 1 week, 1 month, and 6 months after surgery.

Overall, 52 patients (mean age, 59 years) were randomly assigned to the phacoemulsification group (n=25; 25 eyes) or the phacotrabeculectomy group (n=27; 27 eyes). Prior to surgery, patient demographics were well balanced, and no differences in glaucoma severity or measured angle parameters were observed between the groups before surgery. After surgery, all patients had at least 6 months of follow up.

The researchers found no significant difference between study groups for best-corrected visual acuity, intraocular pressure (IOP), or the number of glaucoma medications in preoperative or postoperative visits. 

After surgery, the mean values of all parameters, AOD 500, TISA 500, and TIA 500, were significantly higher in both groups at all postoperative visits compared with their respective baseline measurements (P <.0001 for all), and the mean values of all parameters were significantly higher in the phacoemulsification group than in the phacotrabeculectomy group at all postoperative visits (P <.0001 for all). At the 6-month follow up, researchers noted a mean AOD 500 of 0.383 vs 0.349, a mean TISA 500 of 0.141 vs 0.125, and a mean TIA 500 of 40.1 vs 34.6 in the phacoemulsification and phacotrabeculectomy groups, respectively (P <.0001 for all).

“We found remarkable angle widening following both phacoemulsification and phacotrabeculectomy in [primary angle-closure glaucoma] eyes. Despite similar reduction in IOP and number of glaucoma medications in both groups, the degree of angle widening was greater following phacoemulsification alone up to at least six months after surgery,” according to the investigators.

Limitations of the study included the evaluation of only angle parameters on the horizontal axis and the relatively short follow-up period.

Reference

Ghadamzadeh M, Karimi F, Ghasemi Moghaddam S, Daneshvar R. Anterior chamber angle changes in primary angle closure glaucoma following phacoemulsification versus phacotrabeculectomy. J Glaucoma. Published online January 20, 2022. doi:10.1097/IJG.0000000000001977