Standardizing the Yamane flanged intrascleral haptic fixation: A framework for efficacy, complication mitigation, and reproducible training

Figure 1 Diagram of Yamane flanged intrascleral intraocular lens fixation technique in a right eye. A sterile surgical marking pen is used intraoperatively to identify the scleral fixation sites at the 3 and 9 o’clock meridians. The scleral entry points (purple dots) are marked at 2.0 mm (2 mm to 2.5 mm) posterior to the limbus to guide symmetric tunnel creation. Pre-bent 30-gauge thin-wall needles with different flexion angles (needle #1: Approximately 40°; needle #2: Approximately 55°) are prepared to facilitate ergonomic handling and controlled transscleral entry. The needles are then advanced toward the planned intraocular penetration points (blue dots) along an intrascleral trajectory (approximately 20-30°), creating tunnels of about 2.0-2.5 mm before entering the posterior chamber. This configuration facilitates controlled haptic externalization and stable posterior chamber intraocular lens fixation. Asterisks (*) indicate the three pars plana vitrectomy port entry sites: One superotemporal infusion cannula and two instrument ports placed approximately 3.5 mm posterior to the limbus in the inferotemporal and superior quadrants, respectively. T: Temporal; N: Nasal; OD: Oculus dexter (right eye).

Figure 2 Stepwise illustration of the Yamane technique for flanged intrascleral haptic fixation of a posterior chamber intraocular lens in a right eye, performed in conjunction with pars plana vitrectomy. Trocar cannulas (teal) for 25-gauge pars plana vitrectomy ports placed prior to intraocular lens (IOL) fixation to allow complete vitreous clearance and to reduce the risk of postoperative traction and cystoid macular edema are visible throughout panels A-H; A: Needle marking and needle flexion planning. Blue marking ink dots are visible on the conjunctiva, identifying the planned 30-gauge thin-wall needle entry sites (2.0 mm posterior to the limbus); a reference mark is placed on the needle shaft to guide the intended intrascleral tunnel length (approximately 2.0-2.5 mm); pre-bent 30-gauge thin-wall needles are prepared with different flexion angles (inset: Needle #1: Approximately 40°; needle #2: Approximately 55°); B: Transscleral needle entry; C: Haptic docking into the needle lumen; D: Externalization of the haptic through the scleral tunnel, the externalized haptic is highlighted by an arrow at the scleral exit site; E: Flange formation of the first haptic by low-temperature cautery; F: Externalization of the second haptic and symmetric positioning; G: Flange formation of the second haptic by low-temperature cautery; H: Burial of the flanged haptics and final IOL centration. T: Temporal; N: Nasal.