Tarek S Hassan

Vitrectomy for diffuse diabetic macular edema associated with a taut premacular posterior hyaloid

PURPOSE To evaluate the role of vitrectomy in eyes with diffuse diabetic macular edema associated with a taut posterior hyaloid. METHODS Records of 55 eyes of 50 patients with diabetic retinopathy and diffuse clinically significant diabetic macular edema who underwent vitrectomy with stripping of the premacular posterior hyaloid were reviewed. In all 55 eyes, diffuse diabetic macular edema was present on contact lens examination and confirmed with fluorescein angiography. On fundus examination, the premacular posterior hyaloid was attached and appeared taut. RESULTS The mean preoperative best-corrected visual acuity was 20/160, and the mean final best-corrected visual acuity was 20/80 (P <.0001, Wilcoxon signed rank test), with 27 (49.1%) of the 55 eyes demonstrating improvement in best-corrected visual acuity of 2 or more lines. Fifty-two (94.5%) of the 55 vitrectomized eyes showed improvement in clinically significant macular edema and in 45 eyes (81.8%) the macular edema resolved completely during a mean period of 4.5 months (range, 1 to 13 months). Eyes with macular ischemia and preoperative best-corrected visual acuity of 20/200 or less tended to respond less favorably to vitrectomy than eyes lacking these characteristics. All eyes had at least 6 months of follow-up after surgery, with a mean follow-up of 23.2 months. CONCLUSION In eyes with persistent diffuse diabetic macular edema with a taut premacular posterior hyaloid face unresponsive to laser therapy, vitrectomy with removal of the posterior hyaloid appears to be beneficial in some cases. Careful selection of eyes with favorable preoperative clinical characteristics may improve surgical outcomes.

Vitrectomy for Retained Lens Fragments after Phacoemulsification

PURPOSE Posterior lens fragments after phacoemulsification can be a serious complication of cataract surgery. This study is designed to evaluate the clinical features of eyes after pars plana vitrectomy has been performed to remove posteriorly dislocated lens fragments after phacoemulsification. METHODS The authors performed a retrospective chart review of 126 consecutive eyes of 126 patients with dislocated lens fragments after phacoemulsification, managed with pars plana vitrectomy at Associated Retinal Consultants of Michigan. These eyes were operated on from January 1986 through January 1996. RESULTS The relation of the intervals between cataract surgery and vitrectomy to various postoperative clinical parameters was studied. Clinical features at presentation included elevated intraocular pressure (IOP over 25 mmHg) in 52.4% of the eyes, uveitis in 69.6%, and corneal edema in 50.8%. Initial visual acuity was 20/400 or worse in 73.8% of the eyes. The mean preoperative visual acuity was 20/278 (median, 20/400), whereas the mean final visual acuity was 20/40 (median, 20/50) after a mean follow-up of 18.9 months. Retinal detachments were found in 20 eyes: 7 before vitrectomy and 13 during or after it. After surgery, 44% of eyes achieved a final visual acuity of 20/40 or better and 90% were 20/400 or better. The distribution of best-corrected final visual acuities among the eyes showed statistically significant differences based on the type of intraocular lens (IOL) used, with posterior chamber IOL greater than anterior chamber IOL, and anterior chamber IOL greater than aphakia. Reasons for a poor visual outcome included persistent corneal edema (four eyes), retinal detachment (two eyes), central retinal vein occlusion (two eyes), age-related macular degeneration (two eyes) glaucoma (one year), and endophthalmitis (one eye). CONCLUSIONS There were no statistically significant differences between early (< 7 days) and delayed (8 days or more) vitrectomy when increased IOP, corneal edema, choroidal effusions, cystoid macular edema, and visual acuity were analyzed. The use of vitrectomy to remove posteriorly dislocated lens fragments has been shown to be an effective treatment method that significantly reduces the inflammatory response and hastens visual recovery.

A comparison of visual results and complications in eyes with posterior chamber intraocular lens dislocation treated with pars plana vitrectomy and lens repositioning or lens exchange

PURPOSE To compare the visual results and the postoperative complications in eyes with posterior chamber intraocular lens (PCIOL) dislocation that underwent pars plana vitrectomy with lens repositioning with eyes that underwent pars plana vitrectomy with lens exchange. DESIGN Nonrandomized consecutive comparative case series. PARTICIPANTS Fifty-nine eyes (27 right eyes and 32 left eyes) of 56 subjects (28 women and 28 men) ranging in age from 59 to 90 years. Mean follow-up was 34 months. METHODS A comparison of the best-corrected preoperative visual acuities, final visual acuities, and postoperative complications in subjects with dislocated PCIOLs that underwent pars plana vitrectomy. Logarithm of the minimum angle of resolution (LogMAR)-converted visual acuities were used for comparison. Categorical data were analyzed by Fishers exact test, and population means were compared by a pooled Students t test. MAIN OUTCOME MEASURES Final mean visual acuities, change in mean visual acuities, and postoperative complications. RESULTS For all 59 eyes the mean preoperative visual acuity was 20/152, and the mean final visual acuity was 20/48. Final visual results were similar between the eyes that underwent lens repositioning (20/55) and the eyes that underwent lens exchange (20/43; P = 0.19). Final visual results were also similar between the eyes that underwent lens exchange with sutured PCIOL placement (20/51) and the eyes that underwent lens exchange with anterior chamber intraocular lens (ACIOL) placement (20/38; P = 0.26). Final mean visual acuity in eyes that received an ACIOL (20/38) was better than in eyes that underwent repositioning of the dislocated lens into the ciliary sulcus (20/65; P = 0.01). The mean increase in visual acuities was greater for eyes with ACIOL placement compared with eyes with sutured PCIOL placement (P = 0.01). For all eyes, final visual results were unaffected by a concurrent diagnosis of age-related macular degeneration (20/52; P: = 0.71), glaucoma (20/48; P = 0.95), or postoperative cystoid macular edema (20/55; P = 0.45). Final visual acuities were significantly worse in eyes with a detectable preoperative afferent pupillary defect (20/200; P<0.0001). Postoperative retinal detachments developed in 4 of 29 eyes (14%) that underwent lens repositioning and in 2 of 30 eyes (7%) that had lens exchange (P = 0.42). Postoperative lens subluxations occurred in 6 of 29 eyes (21%) that underwent lens repositioning and in 1 of 30 eyes (3%) that underwent lens exchange (P = 0.05). CONCLUSIONS The final visual results in eyes with dislocated PCIOLs that underwent pars plana vitrectomy with lens repositioning were similar to the visual results obtained in eyes that underwent pars plana vitrectomy with lens exchange. For eyes that underwent lens exchange, final visual results in eyes that received an ACIOL were similar to the visual results obtained in eyes that received a PCIOL; however, eyes with an ACIOL showed a greater increase in mean visual acuity. Eyes with a preoperative afferent pupillary defect had worse final visual results.

Incidence of retinal detachment and visual outcome in eyes presenting with posterior vitreous separation and dense fundus-obscuring vitreous hemorrhage

PURPOSE To determine visual outcomes and the incidence of retinal detachment in eyes presenting with posterior vitreous separation and dense fundus-obscuring vitreous hemorrhage. DESIGN Retrospective consecutive noncomparative interventional case series. PARTICIPANTS Thirty-six eyes (15 right eyes and 21 left eyes) of 34 patients (18 female and 16 male) ranging in age from 42 to 94 years. Mean follow-up was 14 months. METHODS A comparison of the best-corrected initial visual acuities versus final visual acuities after spontaneous resolution of vitreous hemorrhage or surgical intervention. The number of eyes that were found to have retinal tears or that had a rhegmatogenous retinal detachment develop was documented. Logarithm of the minimum angle of resolution-converted visual acuities was used for comparison. Categorical data were analyzed by Fishers exact test, and population means were compared by Students t test. MAIN OUTCOME MEASURES Final mean visual acuities, number of eyes with at least one retinal tear, location of retinal tears, number of eyes that had retinal detachment develop, and the number of eyes repaired with scleral buckling surgery and/or pars plana vitrectomy. RESULTS Twenty-four of 36 eyes (67%) were found to have at least one retinal break (range, 0-4 breaks), with 88% of breaks located in the superior retina. Eleven eyes (31%) had more than one retinal break. Fourteen of 36 eyes (39%) had a rhegmatogenous retinal detachment develop that was repaired with pars plana vitrectomy and scleral buckling. An additional 14 eyes (39%) underwent vitrectomy for nonclearing vitreous hemorrhage. The incidence of retinal detachment in eyes with a history of retinal detachment in the contralateral eye was 75% (P = 0.04). Seven of 14 eyes (50%) with retinal detachment had coexisting proliferative vitreoretinopathy. Most retinal breaks and detachments occurred in emmetropic or myopic eyes. For all 36 eyes the mean preoperative visual acuity was 20/1233, and the mean final visual acuity was 20/62 (P < 0.0001). Eyes that had a macula-off retinal detachment develop had worse final visual outcomes (20/264; P = 0.01), as did eyes that had proliferative vitreoretinopathy develop (20/129; P = 0.04). CONCLUSIONS Acute, spontaneous, nontraumatic posterior vitreous separation with dense fundus-obscuring vitreous hemorrhage is associated with a high incidence of retinal tears and detachment. Close follow-up with clinical examination and ultrasonography is necessary, because many of these eyes may eventually require surgical intervention. Aggressive management with early vitrectomy should be considered when there is a history of retinal detachment in the contralateral eye.

Repair of primary rhegmatogenous retinal detachment using 25-gauge transconjunctival sutureless vitrectomy.

Purpose: To evaluate the anatomical and visual outcomes of primary rhegmatogenous retinal detachment repairs performed using 25-gauge transconjunctival sutureless vitrectomy. Methods: A retrospective, noncomparative interventional case series including 53 consecutive eyes of 52 patients who underwent 25-gauge transconjunctival sutureless vitrectomy to repair primary rhegmatogenous retinal detachment was performed. Variables collected for the study were patient demographics, lens status, preoperative visual acuity, and macular status. Outcome measures included single-operation anatomical success rate, final anatomical success rate, postoperative visual acuity, and surgical complications. Results: The retina was reattached with a single operation in 39 (74%) of 53 eyes. The final anatomical success rate was 100%. The mean time to redetachment was 72 days (range, 13–334 days). Proliferative vitreoretinopathy (64%) and development of new retinal breaks (43%) were the most common reasons associated with redetachment. Mean visual acuity improved from 20/100 to 20/60 (P = 0.001); 55% of eyes had final vision of 20/40 or better. Three eyes (6%) developed postoperative choroidal hemorrhage. Three eyes (6%) developed visually significant macular pucker that required surgery. No postoperative hypotony or endophthalmitis was observed. Conclusions: Repair of primary rhegmatogenous retinal detachments using 25-gauge transconjunctival sutureless vitrectomy resulted in excellent final anatomical success rate and postoperative visual outcomes. However, redetachments due to new tears and/or proliferative vitreoretinopathy resulted in a lower single-operation success rate than those reported with 20-gauge systems.

External versus internal approach to the removal of metallic intraocular foreign bodies.

Objective: To review the management of metallic intraocular foreign bodies (IOFB) at a single institution and to compare the use of internal and external approaches for their removal. Subjects and Methods: A retrospective review was conducted on 70 eyes from 70 patients who underwent surgical removal of a metallic IOFB with either an internal (vitrectomy followed by forceps or internal magnet use) or external approach (large electromagnet) by seven vitreoretinal surgeons at a single institution between 1973 and 1996. Visual acuity and complications occurring with the two approaches were the main outcome measures studied. Results: Overall, patients showed significant improvement in visual acuity following surgical intervention (P < 0.001) despite widely varying surgical techniques. When the authors compared patients treated with an external versus an internal approach they found no statistically significant difference with regard to visual outcome and a trend toward a higher rate of postoperative endophthalmitis in the external approach group. Conclusion: Surgical removal of metallic IOFB results in significant visual improvement. The external approach to the removal of magnetic metallic IOFB remains a viable treatment option in select cases. RETINA 20:364‐369, 2000

Clinical course and surgical treatment of macular epiretinal membranes in young subjects

OBJECTIVE To examine the surgical and nonsurgical visual outcomes of young subjects with idiopathic macular epiretinal membranes (ERMs). DESIGN Retrospective observational and noncomparative interventional case series. PARTICIPANTS Nineteen consecutive subjects (20 eyes) aged 40 years or less with an idiopathic macular ERM. METHODS Group 1: 10 consecutive eyes were initially seen with visual acuity of 20/50 or better; 7 eyes were observed, and 3 eyes with progressive visual loss to <20/50 underwent vitrectomy and membrane peeling. Group 2: 10 consecutive eyes with presenting visual acuity of 20/60 or worse underwent vitrectomy and membrane peeling. MAIN OUTCOME MEASURES Visual acuity, cataract formation, ERM recurrence, operative complications. RESULTS Group 1: With no surgery, visual acuity remained stable or improved in 5 of 10 eyes (50%), with a mean follow-up of 3.7 years. Three of 10 eyes (30%) had visual loss < or =20/60 develop and underwent vitrectomy. Postoperative visual acuity improved an average of 6 lines with a mean follow-up of 17.6 months. Group 2: After vitrectomy, visual acuity improved 2 or more lines in 7 of 10 eyes (70%), with a mean improvement of 4.4 lines and mean follow-up of 29.2 months. Groups 1 and 2: Three of 13 eyes (23%) that underwent vitrectomy had recurrent ERM formation. CONCLUSIONS Young subjects with idiopathic macular ERMs and a presenting visual acuity of 20/50 or better had a favorable visual outcome with observation. Subjects with an initial vision of 20/60 or worse, or those who had a visual decrease to < or =20/60 had significantly improved visual acuity after vitrectomy. ERM recurrence is relatively high after surgery.

25-Gauge pars plana vitrectomy for retained lens fragments.

Purpose:The purpose of this study was to report the outcomes and complications of 25-gauge pars plana vitrectomy for the management of retained lens fragments after complicated cataract surgery. Methods:This is a retrospective consecutive case series of 17 patients who presented with retained lens fragments, ranging from mostly cortex to the entire lens, which were managed using only 25-gauge instrumentation. Results:Eight men and 9 women (mean age, 73.1 years) were followed for a mean of 4.5 months after 25-gauge vitrectomy for removal of retained lens fragments. Mean preoperative visual acuity was 20/427 and mean final postoperative visual acuity was 20/62. Mean surgical operating time was 48.5 minutes. Mean preoperative intraocular pressure was 24.5 mmHg and mean 1-day postoperative intraocular pressure was 17.9 mmHg. No cases required the use of a phacofragmatome, no sutures were required to close the sclerotomies, and there were no cases of postoperative hypotony. Cystoid macular edema and glaucoma developed postoperatively in 29.4% and 5.9% of eyes, respectively. There were no cases of postoperative retinal detachment or endophthalmitis. Conclusion:A 25-gauge vitrectomy technique, without the use of a phacofragmatome, may be a suitable alternative to 20-gauge vitreous surgery using a phacofragmatome in the management of retained lens fragments after complicated cataract surgery. Clinical outcomes and complication rates are comparable to those found in the literature for 20-gauge surgery.

Treatment of naïve lesions in neovascular age-related macular degeneration with pegaptanib.

Purpose: To evaluate the safety and efficacy of pegaptanib sodium injection (Macugen, OSI Eyetech Pharmaceuticals) as primary therapy for previously untreated choroidal neovascular membranes (CNV) associated with wet age-related macular degeneration (AMD). Methods: The authors retrospectively reviewed data of 90 patients with newly diagnosed wet AMD in which pegaptanib was used as primary therapy. Inclusion criteria included CNV of any angiographic subtype and size. Exclusion criteria included any lesion previously treated with photodynamic therapy (PDT), intravitreal triamcinolone, or thermal laser. Outcome measures included pre and post-treatment changes in best-corrected visual acuity, lesion size, lesion angiographic characteristics, and optical coherence tomography (OCT) measurements. Patients were injected every 6 weeks and fluorescein angiography (FA) and OCT imaging were performed after every three injections. Safety assessment was performed by complete ophthalmologic examination pre- and post-injection. Results: Of the patients undergoing primary treatment with pegaptanib, the lesion characteristics were 80% (72/90) occult, 13% (12/90) minimally classic, and 7% (6/90) predominantly classic. Lesion sizes were 50% (45/90) ≤4 disc areas (DA) and 50% (45/90) >4 DA. The mean follow-up was 9.1 ± 2 months (range 6–14 months). Gain of ≥3 lines of vision occurred in 20% (18/90) of patients, stabilization of vision (prevention of three lines of vision loss) occurred in 70% (63/90) of patients, and loss of ≥3 lines of vision occurred in 10% (9/90) of patients, resulting in a 90% response rate. In the patients who gained ≥3 lines of vision, the average number of injections was 3.5. One case of endophthalmitis was recognized. Conclusions: Pegaptanib as primary therapy for naïve CNV lesions offers a 90% rate of improvement or stabilization of vision—outcomes that exceed those reported in the VISION trial.

Hybrid 25- and 27-Gauge Vitrectomy for Complex Vitreoretinal Surgery.

BACKGROUND AND OBJECTIVE The authors report the technique of using the 27-gauge (G) vitreous cutter through 25-G valved cannulas to allow hybrid instrumentation of both gauges. PATIENTS AND METHODS Vitrectomy is initiated with standard placement of 25-G valved cannulas, followed by insertion of a 27-G vitreous cutter through the 25-G cannulas. RESULTS The hybrid procedure emphasizes the advantages of both platforms: The 25-G cutter is more efficient for core vitrectomy and is more rigid to facilitate peripheral vitrectomy; the 25-G platform enjoys a wider armamentarium of instrumentation options; and the smaller profile of the 27-G cutter can be maneuvered more easily into tight surgical planes to act analogous to vertical scissors, with the added benefits of aspiration and spatula-like features. The authors illustrate this technique in three cases: diabetic tractional retinal detachment with dense plaques, posterior stage 4B retinopathy of prematurity, and sutureless scleral fixation of an intraocular lens. CONCLUSIONS Hybrid use of the 25-G and 27-G platforms offers greater versatility for the management of complex vitreoretinal conditions.