Changes of the structure of the anterior chamber after phacoemulsification in primary angle closure glaucoma with cataract by ultrasound biomicroscopy

Abstract

Objective To evaluate the ultrasound biomicroscopic changes of the anterior chamber and the clinical outcome after phacoemulsiftcation and intraocular lens implantation in patients with primary angle closure glaucoma （PACG） and co-existing cataract. Methods Phacoemulsification and intraocular lens implantation were performed on 20 patients （24 eyes） with PACG and co-existing cat- aract in this retrospective study. Best-corrected visual acuity （BCVA）, intraocular pressure （IOP）, cor- neal endothelial cell density, and the number of the antiglaucomatous mediation were documented preoperatively and postoperatively respectively, as well as the main complications in the early period after surgery. UBM was performed preoperatively and 6 months after surgery, and anterior chamber distance （ACD）, angle opening distances00 （AOD500）, trabecular iris angle （TIA）, angle recess area （ARA） and trabecular ciliary processes distance （TCPD） were compared preoperatively and postoperatively respectively. Variance analysis of repeated measured data, Wilcoxon rank sum test and paired t test were used to analyze the data. Results The mean follow-up period was （7.92±4.06） months. In 24 eyes, the mean BCVA improved at lweek （0.83±0.25）, 1 month （0.85±0.19）, 3 months （0.84±0.20） and 6 months （0.81±0.21） postoperatively than preoperatively （0.42±0.21） （F =113.85, P =0.000）.The mean IOP at 1 week, 1 month, 3 months, 6 months and final follow-up postoperatively were （13.88±3.64）mmHg, （13.35±2.93：）mmHg, （13.32±3.02）mmHg, （13.61±3.61） mmHg, and （13.53±3.58）mmHg respectively, which were significant lower than preoperatively （16.03±4.27）mmHg （F =6.67, P =0.000）. The mean ACD, AOD500, TIA and ARA at 6 months postopera- tively were （3.32±0.75）mm, （0.23±0.13）mm, （24.93±11.76）0, （0.17±0.22）mm2 respectively, which were significantly different from preoperatively [（1.90±0.84）mm, （0.11±0.13）mm, （11,61±11.42）° and （0.07±0.08）mm2] （Z =-3.980, t =-3.43, t =-3.33, Z =-3：123, P =0.000, 0.003, 0.004, 0.001）, while the mean TCPD （0.79±0.15）mm had not a significant difference from pre- operatively （0.77±0.22） mm （t =-0.29, P =0.776）. The mean corneal endothelial cell at 6 months postoperatively was （2189.75±518.21） cell/mm2, which had not a significant difference from that preoperatively （2405.46±624.42）cell/mm2 （Z = 1.907, P =0.057）, the mean kinds of antiglaucomatous medication decreased from （2.21±0.61） preoperatively to （0.25±0.61） 6 months postoperatively （Z =5.790, P =0.000）. The main complications in the early period after surgery were found that 10 eyes had mild and moderate corneal edema, 1 eye exudative membrane in pupil. Conclusions Phacoemulsification and ir~traocular lens implantation combined with trabeculectomy performed on the patients with PACG and co-existing cata- ract can effectively deepen the anterior chamber, and remain the configuration of the anterior chamber angle, the drainage of the aqueous humor reopen, as well, the IOP is well controlled postoperatively. Key words: Ultrasound biomicroscopy; Phacoemulsification; Glaucoma; Cataract