Anterior Chamber Angle Changes in Primary Angle-closure Glaucoma Following Phacoemulsification Versus Phacotrabeculectomy: A Prospective Randomized Clinical Trial

Abstract

We used anterior segment optical coherence tomography to investigate anterior chamber angle in primary angle-closure glaucoma (PACG) eyes following phacoemulsification and phacotrabeculectomy. Angle widening was significantly greater after phacoemulsification up to 6 months after the surgery.Purpose: To compare anterior chamber angle following 2 common surgeries for PACG.Methods: One hundred ten glaucoma patients were evaluated in this single center, prospective, randomized clinical trial. Those with concomitant PACG and senile cataract and without a history of ocular surgery, trauma, or chronic miotic use were recruited. Monocular patients were also excluded. Finally, 52 eligible subjects were randomly assigned to phacoemulsification ("Phaco" group, 25 eyes) or phacotrabeculectomy ("Combined" group, 27 eyes) surgeries. A swept-source, anterior segment optical coherence tomography device (CASIA SS-1000 OCT) was used to image the anterior segment. Mask graders used the images to measure the following parameters before and 1 week, 1 month, and 6 months after surgery: angle opening distance at 500 µm, trabecular iris surface area at 500 µm, and trabecular iris angle at 500 µm.Results: There was no significant difference between study groups regarding best-corrected visual acuity, intraocular pressure (IOP), and the number of glaucoma medications in preoperative or postoperative visits (P > 0.076). Also, the measured angle parameters were not statistically significantly different between the 2 groups before surgery (P > 0.123). After surgery, all measured parameters were significantly increased in both groups (P < 0.0001). At the 6-month follow-up, nasal angle opening distance at 500 µm was 0.383 ± 0.027 vs. 0.349 ± 0.017, trabecular iris surface area at 500 µm was 0.141 ± 0.007 vs. 0.125 ± 0.005, and trabecular iris angle at 500 µm was 40.1 ± 12.9 vs. 34.6 ± 3.1 in Phaco and Combined groups, respectively (P < 0.0001 for all).Conclusions: Anterior chamber angle widening by anterior segment optical coherence tomography was observed in PACG patients following surgery and was significantly greater after phacoemulsification compared with combined phacotrabeculectomy at all time points. Similar IOP and medication burden were noted for up to 6 months as secondary outcomes. The contribution of angle changes to the IOP-lowering effect of phacoemulsification in PACG eyes needs further study.

PCME and PCO Rates After Combined Phaco-Trabeculectomy vs. Phaco Alone

“…showed in their study that the rates of PCO, estimated by Nd:YAG laser capsulotomies, were 29% and 30% for patients undergoing combined phaco-trab surgery and phacoemulsi cation alone, respectively. (11) We also assessed PCO rates by Nd:YAG laser capsulotomy and found comparable rates of Nd:YAG laser capsulotomy-free survival between patients who underwent cataract extraction with and without trabeculectomy, with a mean follow-up of 6.9 ± 4.2 and 6.5 ± 4.0 years, respectively. Results remained statistically insigni cant even after adjusting for age and gender.…”

Anterior Segment Changes and Refractive Outcomes after Cataract Surgery Combined with Gonioscopy-Assisted Transluminal Trabeculotomy in Open-Angle Glaucoma

“…Combined cataract surgery and trabeculectomy was recently shown to cause changes in AS configuration and AL. 19 , 20 Even if newer angle-based procedures provide less dramatic IOP-lowering than trabeculectomy, significant changes in AS following combined cataract surgery and MIGS have been reported. 21 , 22 , 23 , 24 Changes in IOP and AS may cause unexpected results in refractive findings following combined surgery, so the chosen IOL calculation formula may become more critical in these cases.…”

Comparison of Lens Extraction Versus Laser Iridotomy on Anterior Segment, Choroid, and Intraocular Pressure in Primary Angle Closure Using Machine Learning

“…It is known that LE in PACG, compared with combined lensectomy and trabeculectomy, is more effective in terms of the ACA opening and allows maintaining the result for at least 6 months after the treatment 55. There are many studies devoted to the advantages of LE over LPI in acute primary closed angle 56,57.…”

“…It is known that LE in PACG, compared with combined lensectomy and trabeculectomy, is more effective in terms of the ACA opening and allows maintaining the result for at least 6 months after the treatment. 55 There are many studies devoted to the advantages of LE over LPI in acute primary closed angle. 56,57 The insufficiency of LPI for the treatment of acute primary closed angle is proven by the fact that 30% of patients subsequently require trabeculectomy due to IOP decompensation.…”