14 EWAP DECEMBER 2023 FEATURE complication and most often resolves as small leaks self-seal. However, long-term hypotony may lead to secondary complications, such as hypotony maculopathy. Initial medical treatment includes topical steroids, cycloplegics, or surgical closure of persistent leaks.” Other complications: CME, ocular hypertension, iris trauma, and retinal trauma are common complications of any secondary lens replacement, regardless of technique, Dr. Pettey and Dr. Nakatsuka wrote. CME, they said, can be managed with topical NSAIDs and steroids or, if needed, intravitreal anti-VEGF or steroid injections. The Yamane technique, according to Dr. Pettey and Dr. Nakatsuka, is susceptible to retained viscoelastic, which can cause elevated IOP. Dr. Nakatsuka has experienced this in up to 20% of cases and usually treats it prophylactically with oral acetazolamide or topical anti - hypertensives. As for retinal trauma, Dr. Kim said if needles are positioned too posteriorly, in theory, they could pierce the peripheral retina and cause a retinal tear or detachment. Dr. Nakatsuka said extra care should be taken with small eyes that may have a shorter pars plana and a more anterior retina insertion leaving the retina vulnerable to puncture and trauma. If there is retinal or corneal damage, such as a retinal tear, CME, or corneal endothelial decompensation, Dr. Kim said these conditions must be treated before IOL replacement or scleral refixation. “As long as there is no permanent damage, when the IOL is replaced and scleral refixation is properly executed, Figure 3. Lens/optic capture can occur after intrascleral haptic fixation, being more common with floppy irises. Source (all): Jeff Pettey, MD, and Austin Nakatsuka, MD Drs. Pettey, Nakatsuka, and Kim have described the common issues encountered during the learning curve of the Yamane IOL fixation technique well. Seeming simple, the technique is not forgiving and every step is crucial. Sources of error contributing to IOL tilt and decentration include failure to mark the limbus at diametrically opposite sites, wrongly identifying the limbus when conjunctivalized, premature or delayed entry into the globe, and asymmetrical scleral tunnel angles. The modifications I describe here are suited to using an IOL with either PMMA or PVDF haptics. Although a thin-walled, small-gauge needle is recommended, using a larger bore needle is easier for threading of the haptic. It would be wise to test if the haptic fits the needle prior to the procedure. Use regional anesthesia but avoid inducing chemosis. I prefer aligning the IOL vertically, as the vertical diameter is shorter than the horizontal. Mark diametrically opposite positions using a toric ring or markerless system, centered on Purkinje 1 image. Mark another point 2.25 mm posterior to the limbus where the haptics are retrieved and adjust this according to the axial length. Create a superior iridectomy and have the pupil miosed a little to prevent the IOL from slipping posteriorly. Create symmetrical scleral tunnels of 2-3 mm length at mid scleral depth, passing the needles circumferential to the limbus. As this is a blind passage into the globe, I palpate the needle tip to ensure that the scleral tunnel length is as planned before the needle enters the eye. I thread the trailing haptic before the leading haptic. Threading more than half the haptic makes threading the second haptic more difficult. The haptics are retrieved simultaneously. This minimizes stress on the haptic optic junction. Flange 1 to 1.5 mm of haptic length and ensure IOL is centered before pushing flange completely into tunnel to avoid hypotony. I suture the incisions if pars plana vitrectomy has been done. These modifications have given me consistent outcomes. I always stop the patient’s anticoagulants as mild vitreous hemorrhage is my most common complication. Hypotony may occur if the flange is not completely buried into the sclera or in a post vitrectomy eye. Optic capture is uncommon provided a peripheral iridectomy has been created, the IOL is fixated posterior to the iris plane and there is no IOL tilt and decentration. I target the first myopic outcome to get plano. Certainly, practice makes perfect. Once mastered, the results are rewarding. Editors’ note: Dr. Chee disclosed no relevant financial interests. Soon-Phaik Chee, MD Senior Consultant, Ophthalmology Eye & Retina Surgeons, #13-03 Camden Medical Centre, 1 Orchard Boulevard, Singapore 248649 cheesp313@gmail.com ASIA-PACIFIC PERSPECTIVES
RkJQdWJsaXNoZXIy Njk2NTg0