Comparative study of silicone versus acrylic foldable lens implantation in primary glaucoma triple procedure

Objective: To compare silicone versus acrylic foldable intraocular lens (IOL) implantation in primary glaucoma triple procedure (PGTP). Design: Prospective, randomized. Participants: A total of 79 eyes of 79 primary open-angle glaucoma (POAG) patients in need of combined surgery were randomized to a silicone IOL group (36 eyes) and acrylic IOL group (43 eyes). Intervention: The study eyes underwent PGTP, which consisted of primary trabeculectomy, phacoemulsification, and posterior chamber IOL implantation. Adjunctive mitomycin C (MMC) (0.5 mg/ml for 1 minute) was used selectively only in patients with one or more risk factors for filtration failure of PGTP. Main Outcome Measures: Snellen visual acuity, intraocular pressure (IOP), slit-lamp biomicroscopy, and number of glaucoma medications were measured, performed, or determined preoperatively and at regular intervals postoperatively. Results: There were no significant differences in the mean number of postoperative glaucoma medications at 1, 2, 3, 4-6, and 9-12 months and at last follow-up (P > 0.05); mean change in corrected visual acuity best attained (P = 0.315) or at last followup (P = 0.223) between the silicone and acrylic groups. Both groups had significant decreases in mean IOP and mean number of medications postoperatively at all times (P < 0.05). However, the postoperative IOP > 25 mmHg and IOP spike > 5 mmHg above preoperative IOP during the first month were significantly higher in the acrylic group (P = 0.026). The mean postoperative IOP at 1 month in the acrylic group was also significantly higher than the silicone group (14.1 +/- 5.0, 11.2 +/- 3.9, P = 0.005). Conversely, there were no significant differences in mean postoperative IOP at 2, 3, 4-6, and 9-12 months and at last follow-up between the silicone and acrylic groups (P > 0.05). Suture removal or release occurred significantly more frequently in the acrylic IOL group during the first month and the first 2 months (48.8% and 60.5%) than the silicone group (25.0% and 36.1%, P = 0.030 and 0.031, respectively). There were no significant differences in postoperative complications or surgical interventions between the two groups (P > 0.05). Conclusions: During the first year following the PGTP with selective use of MMC, there were no significant differences in the medical dependency or visual outcomes or complications between the silicone and acrylic groups. Both groups attained significant decreases in IOP postoperatively. However, the mean IOP was significantly higher in the acrylic than the silicone group at 1 month postoperatively, and postoperative IOP > 25 mmHg and IOP spike > 5 mmHg above preoperative IOP were significantly greater in the acrylic group. There were significantly more suture releases in the acrylic IOL group than the silicone IOL group in the first 2 months postoperatively.