Extraocularly Manipulated Flangeless Intrascleral Haptic Fixation of Intraocular Lens Using Zigzag Needles

To evaluate a novel, flangeless intrascleral intraocular lens (IOL) fixation technique using zigzag 27-gauge needles that prioritizes extraocular maneuvers and eliminates the need for sutures, heat-based flanging, or specialized equipment.

This study evaluated patients who underwent intrascleral IOL fixation with 27-gauge needles at Osaka Red Cross Hospital between March and September 2024. The surgical procedure was performed using a three-piece NX-70 IOL. Standard 27-gauge needles were bent (the leading needle was bent at a slightly obtuse angle and the trailing needle was bent in a zigzag shape in three stages) to guide the IOL haptics extraocularly. Custom silicone pieces (approximately 1 mm, cut from a standard phaco-sleeve) were temporarily attached to the haptic ends to secure them during the process. The haptics were then retracted into limbal-parallel scleral tunnels without flange fixation. Patients were evaluated preoperatively and at one month postoperatively for best-corrected visual acuity (BCVA), corneal endothelial cell density (ECD), and IOL tilt.

Eighteen eyes of 17 patients (mean age: 74.3 ± 11.4 years) were included. At one month postoperatively, the mean BCVA improved from 0.56 ± 0.66 logMAR to 0.15 ± 0.40 logMAR. The mean ECD decreased from 2243 ± 319 cells/mm² to 1999 ± 502 cells/mm². The mean IOL tilt was 5.74 ± 2.95 degrees. Postoperative complications occurred in one eye each (5.6%): vitreous hemorrhage (which resolved within two weeks), temporary intraocular pressure elevation, transient corneal edema, and one intraoperative rhegmatogenous retinal detachment (unrelated to the IOL fixation technique itself). IOL repositioning due to tilt was required in one patient (5.6%), and no cases of iris capture were observed.

This modified flangeless intrascleral IOL fixation technique using zigzag-bent 27-gauge needles was feasible using standard surgical instruments and yielded acceptable preliminary short-term clinical outcomes in this small case series. Larger comparative studies with longer follow-up are required to evaluate long-term IOL stability and safety.