Matthew A. Thomas

Visual Results after Surgical Removal of Subfoveal Choroidal Neovascular Membranes

PURPOSE The authors report their experience with the surgical removal of subfoveal choroidal neovascularization. Correlations between preoperative characteristics and final postoperative visual acuity are explored. METHODS A retrospective study of 159 consecutive patients was performed between February 1990 and August 1993. Follow-up of 2 or more months was available for 147 eyes: presumed ocular histoplasmosis syndrome, 67 eyes; age-related macular degeneration, 41 eyes; myopia, 10 eyes; multifocal choroiditis, 9 eyes; idiopathic, 8 eyes; angioid streaks, 4 eyes; and miscellaneous, 8 eyes. RESULTS Sixty-seven eyes had presumed ocular histoplasmosis syndrome: mean follow-up was 10.5 months. Visual acuity was stable or improved in 56 (83%) eyes and 20/40 or greater in 21 (31%) eyes. Mean interval to best visual acuity was 3 months. A recurrence rate of 37% had no significant effect on final visual outcome (P = 0.952). Forty-one eyes had age-related macular degeneration: mean follow-up was 15 months. Visual acuity was improved in only five (12%) eyes and was 20/40 or greater in only two (5%) eyes. The interval to best visual acuity was 5 months. A recurrence rate of 27% had not significant effect on final visual outcome (P = 0.31). The visual results and recurrence rates for eyes with less common disorders are presented. CONCLUSION The surgical excision of subfoveal choroidal neovascularization may stabilize or improve visual acuity in selected cases. Patients with focal disorders of the retinal pigment epithelium-Bruchs membrane complex appear to have a better surgical outcome than those with diffuse disease.

Surgical Management of Subfoveal Choroidal Neovascularization

BACKGROUND Subfoveal choroidal neovascularization (CNV) usually is associated with a poor visual prognosis. Laser photocoagulation of certain subfoveal membranes secondary to age-related macular degeneration (ARMD) appears preferable to observation based on recent Macular Photocoagulation Study (MPS) findings but is associated with decreased vision. The authors explored the use of vitreoretinal surgical techniques as an alternative method of eradicating subfoveal CNV. METHODS After vitrectomy, a small retinotomy technique was used to extract or disconnect from the choroidal circulation subfoveal CNV in 58 eyes. There were 33 eyes with ARMD, 20 eyes with presumed ocular histoplasmosis, and 5 eyes with miscellaneous etiologies. Five eyes also received subfoveal RPE patches. RESULTS With limited follow-up, significant improvement in vision (defined as 2 Snellen lines) was achieved in 7 of 22 eyes with ARMD CNV removal (1 eye 20/20), 0 of 4 eyes with ARMD CNV removal and RPE patches, and 1 of 7 eyes with ARMD CNV disconnection. Significant improvement was achieved in 6 of 16 eyes with presumed ocular histoplasmosis removal and 0 of 4 eyes with presumed ocular histoplasmosis CNV disconnection. In 5 eyes with miscellaneous CNV, 2 improved (20/20 and 20/40). CNV recurred in 29%. CONCLUSIONS Some patients with subfoveal CNV appear to benefit from surgical removal. Only rarely do eyes with ARMD improve. Longer-term follow-up and refined case selection are required before this approach can be widely recommended.

Surgical removal of subfoveal neovascularization in the presumed ocular histoplasmosis syndrome

We treated two patients with presumed ocular histoplasmosis, subfoveal neovascular membranes, and progressive visual acuity loss to 20/400. Vitreoretinal surgical techniques were used to remove the subfoveal membranes. Visual acuity returned to 20/20 with seven months of follow-up in one patient (Case 1) and to 20/40 with three months of follow-up in the other patient (Case 2). No evidence of persistent or current subretinal neovascular membranes in either patient have been noted. These preliminary results suggest that vitreoretinal surgical techniques may be successful in mechanically removing subfoveal neovascular membranes with preservation of overlying neurosensory retina and thus preservation of central visual acuity.

Nuclear Sclerotic Cataract after Vitrectomy in Patients Younger than 50 Years of Age

PURPOSE To evaluate the occurrence of cataract formation after pars plana vitrectomy and gas-fluid exchange in patients younger than 50 years of age. METHODS Twenty-eight patients younger than 50 years of age with bilaterally symmetric crystalline lenses underwent pars plana vitrectomy and gas-fluid exchange in one eye. Postoperatively, lens photographs were used to assess any asymmetry between the surgical and nonsurgical eye. Lens photographs were graded by three independent masked observers using the Lens Opacities Classification System III (LOCS III). Significant cataract progression was defined as either cataract extraction in the surgical eye or a greater than a 0.9 LOCS III unit difference in lens opacity between the surgical and nonsurgical eye. Results were compared with 28 patients older than 50 years of age who had undergone identical surgery. RESULTS In only 7% of patients younger than 50 years of age (mean age, 36.5 years; range, 16-47 years) did significant lens opacity develop in the surgical eye compared with the nonsurgical eye during the follow-up period (mean follow-up, 25.4 months; range, 12-43 months). Of patients older than 50 years of age (mean age, 68.2 years; range, 51-85 years), 79% developed significant lens opacity in the surgical eye compared with the nonsurgical eye during the follow-up period (mean follow-up 27.3 months; range, 12-49 months). The difference in cataract progression between patients younger than 50 years of age and patients older than 50 years of age was statistically significant (P < 0.0000001). CONCLUSION Pars plana vitrectomy with gas-fluid exchange is minimally cataractogenic within the first few years in patients younger than 50 years of age.

Vitrectomy for Premacular Fibroplasia: Prognostic Factors, Long-term Follow-up, and Time Course of Visual Improvement

Two hundred seventy eyes with premacular fibroplasia consecutively treated by pars plana vitrectomy and membrane peeling were reviewed. This study is among the largest series with long-term follow-up reported to date. Visual improvement of two or more lines was achieved in 43% of eyes at 6 to 12 months, in 54% at 1 to 2 years, in 60% at 2 to 3 years, and in 58% at 3 to 5 years. Overall, complications occurred in 34 eyes (13%). Cataract progression after vitrectomy was noted in 106 (57%) of phakic eyes at 3 to 5 years, and 43 of these eyes underwent subsequent cataract extraction. Mean time to best visual acuity after vitrectomy was slightly less than 1 year for all eyes unless they had cataract worsening with subsequent cataract extraction (1.9 years). Significant factors affecting visual outcome were: preoperative lens status, visual acuity before vitrectomy, duration of preoperative symptoms of distortion and/or blurred vision, and the occurrence of intraoperative complications.

Visual Field Loss After Pars Plana Vitrectomy With Air/Fluid Exchange

PURPOSE To report the postoperative finding of a dense, permanent, peripheral temporal visual field defect in the treated eyes of three patients who underwent pars plana vitrectomy with air/fluid exchange. METHODS The patients charts were reviewed. RESULTS Visual field loss after pars plana vitrectomy and air/fluid exchange occurs and may be caused by mechanical trauma to the optic nerve head. CONCLUSION Great caution is advised when aspirating directly over the optic nerve with any extrusion instrument.

Submacular surgery trials randomized pilot trial of laser photocoagulation versus surgery for recurrent choroidal neovascularization secondary to age-related macular degeneration: I. Ophthalmic outcomes. Submacular Surgery Trials Pilot Study report number 1

PURPOSE To report complications and changes in vision during 2 years of follow-up of patients with age-related macular degeneration assigned randomly to surgical removal or to laser photocoagulation of subfoveal recurrent neovascular lesions in a pilot trial designed to test methods, to refine estimates of outcome rates, and to project patient accrual rates for a larger multicenter randomized trial to evaluate submacular surgery. PATIENTS AND METHODS Eligible patients with previous laser photocoagulation of extrafoveal or juxtafoveal choroidal neovascularization secondary to age-related macular degeneration were enrolled at 15 collaborating clinical centers. Assignments to treatment arm were made by personnel at a central coordinating center. Adherence to eligibility criteria and treatment assignment was assessed centrally at a photograph reading center. Patients were examined at 3, 6, 12, and 24 months after treatment for data collection purposes. Outcome measures reported include treatment complications, adverse events, requirements for additional treatment, and 2-year changes in visual acuity from baseline. RESULTS Of 70 patients enrolled, 36 were assigned to laser photocoagulation and 34 to submacular surgery; all were treated as assigned. One patient in each group died before the 2-year examination. Visual acuity was measured at the 2-year examination for 31 of the surviving patients (89%) in the laser arm and for 28 of the surviving patients (85%) in the surgery arm. The 2-year measurements for 36 of the 59 patients (61%) were made by an examiner masked to treatment assignment and to the identity of the study eye. Improvements and losses of visual acuity were observed in both treatment arms; 20 of 31 study eyes (65%) in the laser arm and 14 of 28 study eyes (50%) in the surgery arm had visual acuity 2 years after enrollment that was better than or no more than 1 line worse than the baseline level. Changes in visual acuity and the size of the central macular lesions from baseline to the 2-year examination were similar in the treatment arms. Few serious complications were observed in either arm at the time of initial treatment; serious adverse events were rare. During follow-up, 11 laser-treated eyes and 18 surgically treated eyes had additional intraocular procedures. CONCLUSIONS The data from this pilot trial suggest no reason to prefer submacular surgery over laser photocoagulation for treatment of patients with age-related macular degeneration who have lesions similar to those studied in this pilot trial. Any clinical trial designed to compare submacular surgery with laser photocoagulation in eyes with age-related macular degeneration and subfoveal recurrent neovascular lesions must enroll several hundred patients in order to reach a statistically valid conclusion regarding differences between these two methods of treatment with respect to either changes in visual acuity or complication rates.

The surgical removal of subfoveal choroidal neovascularization. Ingrowth site as a predictor of visual outcome

Purpose: The authors determine the significance of location of the ingrowth site of subfoveal choroidal neovascularization (CNV) as a preoperative indicator of postsurgical visual acuity. Design: A retrospective review is given of preoperative fluorescein angiograms and color fundus photographs for 84 eyes with subfoveal CNV due to the following etiologies: presumed ocular histoplasmosis syndrome (POHS) = 67 eyes; multifocal choroiditis= 9 eyes; idiopathic = 8 eyes. The ingrowth site of the subfoveal CNV was classified as identifiable or not identifiable. If identifiable, the ingrowth site was further classified as extrafoveal, juxtafoveal, or subfoveal. Correlations between CNV ingrowth site location and postoperative visual acuity were made. Results: The ingrowth site for subfoveal CNV was identifiable preoperatively in 60 eyes (71%). Of 31 eyes with an extrafoveal ingrowth site, 18 (60%) had a final visual acuity of 20/40 or better. Of 12 eyes with a juxtafoveal ingrowth site and 18 eyes with a subfoveal ingrowth site, only 2 (7%) had a final visual acuity of 20/40 or better. If the ingrowth site was not identifiable or identifiable and subfoveal in location (N=42), 76% of eyes had a final visual acuity of 20/200 or worse. Conclusion: The ingrowth site of subfoveal CNV can be identified in the majority of eyes with POHS, multifocal choroiditis, or idiopathic membranes. A significant number of subfoveal CNV will have an extrafoveal ingrowth site. Eyes with an extrafoveal ingrowth site have a favorable visual prognosis after the surgical removal of the CNV. If the ingrowth site is subfoveal or not identifiable, the visual prognosis after surgery is guarded.

Surgical Removal of Subfoveal Choroidal Neovascularization in Presumed Ocular Histoplasmosis: Stability of Early Visual Results

PURPOSE The authors assess the stability of visual acuity outcomes after the surgical removal of subfoveal choroidal neovascularization in a large series of patients with presumed ocular histoplasmosis syndrome (POHS). METHODS A retrospective study of 117 consecutive patients undergoing vitrectomy between February 1990 and December 1994 was performed. All patients underwent the surgical removal of subfoveal choroidal neovascularization due to POHS and had at least 3 months of follow-up. Postoperative Snellen visual acuity was the primary study endpoint. RESULTS With a median follow-up of 13 months (range, 3-46 months), 35% of patients had postoperative visual acuity of 20/40 or better, and 40% had improvement of three or more Snellen lines after surgery. In a subset of 54 eyes followed for at least 1 year, 91% showed stable or improved vision between the 3- and 12-month time points, and 85% showed stable or improved vision between 3 months and final visit. CONCLUSION Follow-up of a large number of patients appears to confirm initially encouraging results and to suggest stability of beneficial effect after the surgical removal of subfoveal choroidal neovascularization in POHS.

Interferon Alfa-2a in the Treatment of Subfoveal Choroidal Neovascularization

We prospectively evaluated the effect of interferon alfa-2a on subfoveal choroidal neovascularization. Eight patients with recurrent subfoveal choroidal neovascularization after surgical excision and 12 patients with subfoveal choroidal neovascularization without previous surgical excision received interferon alfa-2a (3.0 to 6.0 million U/m2 of body surface area), every other night for an average of 12 weeks. Mean follow-up was nine months. Visual acuity improved in two of 20 (10%), remained stable in seven of 20 (35%), and worsened in 11 of 20 (55%) patients. The fluorescein angiogram improved in two of 20 (10%), remained stable in three of 20 (15%), and deteriorated in 15 of 20 (75%) patients. All patients had side effects, which led to the discontinuation of therapy in five of 20 (25%) patients. Side effects included flulike symptoms, leukopenia, thrombocytopenia, increased liver enzymes, alopecia, fever, nausea, and suicidal depression. Interferon alfa-2a failed to improve visual acuity or the fluorescein angiographic appearance of subfoveal neovascular membranes in 90% of cases and was associated with marked side effects. We discourage the widespread use of interferon alfa-2a in the treatment of choroidal neovascularization.