Technique for Sutured Scleral Fixation of One-Piece Hydrophobic Acrylic Intraocular Lenses Dislocated Into the Vitreous.

PURPOSE: To present a suturing technique for safe refixation of posteriorly dislocated one-piece hydrophobic acrylic intraocular lenses (IOLs). METHOD: Retrospective data analysis of a series of 12 cases operated with vitrectomy, followed by IOL relocation to the retropupillary area, after which polypropylene sutures are passed through the optic-haptic junctions of the dislocated IOL and subsequently secured to the sclera. RESULTS: In all cases, the IOL remained centered throughout the follow-up period (mean 10.5 months, range 3 weeks-36 months). One case was complicated by vitreous hemorrhage the first postoperative day and later cystoid macular edema. Visual acuity was not compromised at the end of follow-up. CONCLUSION: The presented technique is safe and provides long-term stable refixation in cases of late posterior dislocation of a one-piece hydrophobic acrylic IOL. The risk that sutures looped around haptics will slip off the haptic is thereby avoided.

Radial optic neurotomy in the porcine eye without retinal vein occlusion.

OBJECTIVE: To demonstrate the histopathologic changes in the porcine eye without retinal vein occlusion after radial optic neurotomy (RON). METHODS: A RON was performed in 14 normal eyes of 12 Yorkshire Cross pigs. One radial stab incision at the edge of the nasal optic nerve head was made using a 20-gauge microvitreoretinal blade (Visitec) while the intraocular pressure was elevated. Surgery was concluded when hemostasis was achieved. Weekly ophthalmoscopic examinations were performed. Group 1 eyes (4 eyes of 2 pigs) were enucleated at the end of surgery. Group 2 eyes (4 eyes of 4 pigs) were enucleated 1 week postoperatively, and group 3 eyes (4 eyes of 4 pigs) were enucleated 3 weeks postoperatively. In group 4 (2 eyes of 2 pigs), animals underwent vitrectomy and RON, and eyes were enucleated 3 weeks postoperatively. RESULTS: Ophthalmoscopic examination demonstrated engorged blood vessels at the RON site up to 3 weeks after surgery with minimal or no hemorrhage. Histological examination of the optic nerve demonstrated foci of hemorrhage, interstitial edema, reactive gliosis, and rare inflammatory cells. At 3 weeks, there was complete axonal nerve fiber loss distal to the neurotomy site. CONCLUSIONS: After RON, marked gliosis and complete axonal nerve fiber loss occur at the neurotomy site. Although bleeding was rare intraoperatively in this porcine model, hemorrhage and interstitial edema were present within the optic nerve at the neurotomy site histologically. Clinical Relevance Radial optic neurotomy remains a controversial method of treatment for central retinal vein occlusion. To our knowledge, this is the first study in the literature describing the histopathologic findings after RON.

Effects of indocyanine green on the retina and retinal pigment epithelium in a porcine model of retinal hole.

PURPOSE: This study was designed to emulate human macular hole surgery and to test the effects of indocyanine green (ICG) on the retina and retinal pigment epithelium (RPE). METHODS: Yorkshire Cross pigs (n = 23) underwent vitrectomy, separation of the posterior cortical vitreous, and creation of a single retinal hole. In three study groups (n = 6, each group), air-fluid exchange was performed, following which balanced salt solution (BSS), 1.0% ICG, or 0.5% ICG was applied over the retinal hole. In one additional group (n = 5), 0.5% ICG was injected into the fluid-filled eye. At 4 weeks, the eyes were examined clinically, and fundus photographs were obtained before enucleation and light microscopic examination. RESULTS: Clinical evaluations documented a statistically significant difference between study groups (P = 0.036). There was a higher rate of moderate or severe RPE atrophy among animals where 1% or 0.5% ICG was applied in air-filled eyes (83% and 67%, respectively) compared with BSS controls (17%) and fluid-filled eyes receiving 0.5% ICG (40%). Histologic evaluation demonstrated a statistically significant difference between groups (P = 0.044), with extensive outer retinal degeneration observed in air-filled eyes receiving 1% or 0.5% ICG (66% and 60%, respectively) compared with BSS controls or fluid-filled eyes receiving 0.5% ICG (none of the eyes in either group). None of the study groups had any changes in the inner retina except at the retinal hole site. CONCLUSIONS: Retina exposed to ICG concentrations used in human vitreoretinal surgery had greater RPE atrophy and outer retinal degeneration than control eyes undergoing the same surgery without ICG. Eyes filled with infusion fluid during ICG injection had less damage to the RPE and outer retina than did air-filled eyes receiving ICG.