Management of complete iridocorneal apposition after vitrectomy

Surgical Results for Proliferative Vitreoretinopathy

We reviewed 88 consecutive eyes that underwent vitrectomy for retinal detachment with proliferative vitreoretinopathy (PVR) and were followed a minimum of six months. A primary goal of the surgery was the meticulous trimming of the vitreous base in hopes of decreasing the incidence of post-operative reproliferation and anterior PVR. Those eyes with anterior PVR had aggressive release of vitreous base contraction (anteroposterior and circumferential) with intraocular scissors. All posterior tractional membranes were removed. All eyes received long-acting gas for postoperative retinal tamponade. Macular reattachment was achieved in 78 (88.6%) eyes. Forty-six (52.3%) obtained at least 5/200 vision. Seventeen (19%) eyes were re-operated at least once. We compared the importance of initial lens status (pseudophakic, aphakic, phakic), need for relaxing retinotomy, presence of anterior PVR, and history of previous vitrectomy on the anatomic and visual results. No single factor was responsible for a statistically significant effect on either vision or anatomic success, except for the need for a relaxing retinotomy, which carried with it a decreased chance of an eye obtaining 5/200 vision (Fisher's exact test, p = 0.03).

Pupillary Block Glaucoma After Pars Plana Vitrectomy with Air-Fluid Exchange in Pseudophakic Air-Filled Eye

Pupillary block is seen after pars plana vitrectomy (PPV) with gas or silicone oil endotamponade in aphakic eyes. A case of a pseudophakic patient with pupillary block glaucoma related to the migration of air into the anterior chamber was reported. A 76-year-old woman underwent combined PPV with air endotamponade and uncomplicated cataract extraction for epiretinal membrane and cataract. On postoperative day 1, she had an 80% air fill of the anterior chamber. She returned 6 days later with pupillary block glaucoma. She was managed with a surgical peripheral iridectomy, posterior synechiolysis, and evacuation of the air from the anterior chamber. The risk of pseudophakic pupillary block glaucoma after PPV with air tamponade may be increased with inflammation due to combined PPV and cataract extraction, zonular weakness, and efflux of air from the vitreous cavity into the anterior chamber. Early detection and treatment is recommended to avoid permanent sequelae.

Mechanisms of intraocular pressure elevation after pars plana vitrectomy

A prospective study of 222 consecutive patients undergoing pars plana vitrectomy was done to determine the incidence and mechanisms of postoperative intraocular pressure (IOP) elevation. Within 48 hours of surgery, postoperative IOP increased by at least 5 to 22 mmHg in 136 eyes (61.3%) and to 30 mmHg or more in 79 eyes (35.6%). Presumed mechanisms of open-angle glaucoma included intraocular gas expansion (28.4%), inflammatory trabecular meshwork obstruction (4.5%), silicone oil-related glaucoma (3.6%), and erythroclastic glaucoma (2.2%). Closed-angle mechanisms included pupillary block glaucoma (6.8%) and ciliary body edema (3.6%). Factors which were associated with postvitrectomy pressure elevation included placement of a scleral buckle, either intraoperatively (P = 0.003) or before vitrectomy (P = 0.001), intraoperative scatter endophotocoagulation (P = 0.041), intra-operative lensectomy (P = 0.024), and development of postoperative fibrin membranes (P = 0.038). Surgery was required to lower IOP or relieve pupillary block in 25 eyes (11.3%).

Management of anterior and posterior proliferative vitreoretinopathy. XLV. Edward Jackson memorial lecture

Proliferative vitreoretinopathy is a composite of anterior and posterior proliferation producing multidirectional tractional forces and resultant complex management problems. In a series of 98 consecutive cases of nondiabetic, nontraumatic proliferative vitreoretinopathy, anterior proliferation caused retinal detachment in 58 patients. Relaxation of circumferential traction created by anterior proliferation in the vitreous base and its contiguous surfaces is achieved by multiple radial incisions in the vitreous base and associated anterior retina is eliminated by incision of the displaced anterior and posterior hyaloid surfaces. The subsequent release of posterior traction and determination of residual traction by sequential fluid-air exchange before final tamponade with longer acting gas or silicone oil is described. Total retinal reattachment was achieved in 23 of 33 eyes (70%) with only posterior proliferation compared to 27 of 47 eyes (57%) with significant anterior proliferation. Retinal attachment posterior to the scleral buckle was achieved in 27 of 33 eyes (82%) and 37 of 47 eyes (79%), respectively. Although the success rate was less in eyes with anterior proliferation, the retinal reattachment rates in the two groups approached comparability as experience and understanding of the clinical significance increased.