William E. Smiddy

Vitrectomy for diabetic macular edema associated with a thickened and taut posterior hyaloid membrane

PURPOSE To evaluate the surgical results in a series of patients with diabetic macular edema associated with traction from a thickened and taut posterior hyaloid membrane and to identify features associated with better visual outcome. METHODS We reviewed the clinical records of ten consecutive patients who underwent pars plana vitrectomy in one eye for diabetic macular edema that was preoperatively attributed to thickening and traction of the posterior hyaloid membrane. RESULTS Best-corrected, preoperative visual acuity was 20/200 in seven eyes, 20/300 in one eye, and 20/400 in two eyes. Intraoperatively, seven patients were found to have an attached posterior hyaloid membrane which was thickened and taut. Among these seven patients, postoperative best-corrected visual acuity improved by six lines in two eyes, by five lines in one eye, by two lines in one eye, and remained within one line of preoperative visual acuity in three eyes. The other three patients had an epiretinal membrane simulating an attached and thickened posterior hyaloid membrane. CONCLUSIONS Vitrectomy effectively improved visual acuity in some eyes with diabetic macular edema associated with traction from a thickened and taut posterior hyaloid membrane. Despite careful preoperative examination with a fundus contact lens, however, in some patients it may be difficult to assess how the posterior hyaloid membrane contributes to the macular edema. In selected patients, early surgical intervention may be associated with better visual outcome.

Endophthalmitis after Pars Plana Vitrectomy

Purpose: To describe the clinical course and incidence of culture-proven Postvitrectomy endophthalmitis in 18 patients from five academic centers and three private practices. Methods: Patients undergoing pars plana vitrectomy for recent trauma or endophthalmitis were excluded. The average age was 58 years (range, 21–85 year). Sixty-one percent of the patients (11/18) had diabetes mellitus. The indication for initial vitrectomy was vitreous hemorrhage (n = 10), macular epiretinal membrane (n = 3), recurrent retinal detachment with proliferative vitreoretinopathy (n = 2), retinal detachment with retinoschisis (n =1), proliferative diabetic retinopathy with tractional retinal detachment (n =1), and dislocated intraocular lens (n =1). None of these eyes received prophylactic intraocular antibiotics during the vitrectomy. Results: All eyes were treated with intraocular antibiotics after the diagnosis of Postvitrectomy endophthalmitis was made. Final visual acuity ranged from 20/20 to no light perception and included five eyes with 20/50 or better visual acuity and 11 eyes with less than 5/200 visual acuity. Nine eyes had a final visual acuity of no light perception. Of the 16 eyes infected with a single organism, 71 % (5J7) of eyes infected with coagulasenegative staphylococci retained 20/50 or better final visual acuity compared with no eyes (0/9) infected with other organisms ( P = 0.005). Two eyes infected with both coagulase-negative Staphylococcus and Streptococcus had a final visual acuity of 20/ 400. Three eyes with a total hypopyon later had enucleation or evisceration. Based on the data from four medical centers, the incidence of endophthalmitis after pars plana vitrectomy performed over the last 10 years was 9/12,216 (0.07%). Conclusion: Endophthalmitis after vitrectomy is rare. Postvitrectomy bacterial endophthalmitis caused by organisms other than coagulase-negative staphylococci has a poor visual prognosis.

Long--term Visual Outcomes in Patients with Successful Macular Hole Surgery

OBJECTIVE The purpose of the study is to determine the long-term visual outcomes in patients undergoing successful macular hole surgery. DESIGN A consecutive series of eyes with an anatomically successful macular hole surgical result and at least 1 year postoperative follow-up information was identified and studied. Preoperative and postoperative visual acuities were measured in accordance with the Early Treatment Diabetic Retinopathy Study protocol. MAIN OUTCOME MEASURES Visual acuity, improvement of visual acuity, and rate of final visual greater than or equal to 20/40 were measured. RESULTS The median visual acuity increased from 20/125 before surgery to 20/50 1 year after surgery (93 eyes) and to 20/30 at 36 months after surgery (68 eyes). The trend for improvement in visual acuity after 1 year after surgery was statistically significant. The postoperative visual acuity was greater than or equal to 20/40 in 15 (17%) eyes at 3 months and 53 (78%) at 36 months. Before surgery, 12 (13%) eyes were pseudophakic, and 77 (83%) were pseudophakic at 36 months. Median visual acuity in the fellow eye was 20/32 at baseline and 20/32 at 36 months. The visual acuity in the study eye was better than in the fellow eye in 36 (39%) patients at 36 months after surgery. CONCLUSIONS Visual acuity in patients after anatomically successful macular hole surgery continues to improve even beyond 1 year after surgery. Although substantial improvement occurs soon after cataract extraction, further improvement in visual acuity continues for 2 years thereafter.

Staphylococcus aureus Endophthalmitis: Antibiotic Susceptibilities, Methicillin Resistance, and Clinical Outcomes

PURPOSE To investigate the antibiotic susceptibility and clinical outcomes of endophthalmitis caused by methicillin-sensitive Staphylococcus aureus (MSSA) versus methicillin-resistant (MRSA) S. aureus. DESIGN Retrospective, consecutive case series. METHODS Charts of 32 patients with culture-proven S. aureus endophthalmitis seen at the Bascom Palmer Eye Institute from January 1, 1995, through January 1, 2008, were reviewed. Antibiotic susceptibility profiles, identified using standard microbiologic protocols, and visual acuity at 1 and 3 months were the main outcome measures. RESULTS MSSA was recovered from 19 (59%) of 32 patients and MRSA was recovered from 13 (41%) of 32 patients. Causes included cataract surgery in 18 (56%) of 32 patients, endogenous in 5 (16%) of 32 patients, bleb association in 4 (13%) of 32 patients, pars plana vitrectomy and ganciclovir implantation in 3 (9%) of 32 patients, and trauma in 2 (6%) of 32 patients. All isolates were sensitive to vancomycin. MSSA isolates were sensitive to all tested antibiotics, except one that exhibited fluoroquinolone resistance. In the MRSA group, frequent resistance occurred with the fourth-generation fluoroquinolones (moxifloxacin, 5 of 13 patients [38%]; gatifloxacin, 5 of 13 patients [38%]). The median presenting visual acuity was approximately hand movements for both MSSA and MRSA eyes. All eyes received intravitreal antibiotics. Pars plana vitrectomy was performed on 47% of MSSA and 61% of MRSA patients. A final visual acuity of 20/400 or better at 3 months was achieved in 59% of MSSA and 36% of MRSA patients (P = .5). CONCLUSIONS Although all MSSA and MRSA isolates were sensitive to vancomycin, fewer than half of MRSA isolates were sensitive to the fourth-generation fluoroquinolones. Visual acuity outcomes between MRSA and MSSA eyes were not significantly different.

Primary Intraocular Lens Implantation in the Setting of Penetrating Ocular Trauma

PURPOSE To evaluate the clinical outcome of patients who underwent lensectomy and intraocular lens (IOL) implantation at the time of primary repair of a penetrating ocular injury. METHODS A review of 14 patients who sustained cataracts and lens rupture in the setting of a corneal laceration to determine anatomic and visual outcome, in addition to complications related to the primary IOL. RESULTS The IOL remained anatomically stable in all 14 patients with no complications encountered at implantation or after surgery. Final visual acuity in 9 of the 14 patients was 20/40 or better. Six patients underwent pars plana vitrectomy for removal of an intraocular foreign body. CONCLUSION Intraocular lens implantation at the time of lensectomy and primary repair of a corneal laceration allows good visual rehabilitation with restoration of binocular function and serves as an alternative to contact lens correction in select patients.

Long-term anatomic and visual acuity outcomes after initial anatomic success with macular hole surgery

PURPOSE To investigate the anatomic and visual outcomes in patients with initial anatomic success after macular hole surgery and with at least 5 years of follow-up. DESIGN Retrospective, noncomparative, consecutive case series. METHODS Medical records of all patients who underwent surgery for idiopathic full-thickness macular holes by two surgeons (W.E.S., H.W.F.) at the Bascom Palmer Eye Institute between January 1, 1991, and December 31, 1996, were reviewed. All patients who had initial anatomic success with macular hole surgery and who had 5 years or more of follow-up postoperatively were included in the study. Main outcome measures included the rate of macular hole reopening and visual acuity outcomes. RESULTS Seventy-four eyes of 66 patients with a median age of 68.0 years (range, 45.0-86.8 years) were identified. The median duration of macular hole was 6.0 months (range, 1.1-93.8 months), and the median duration of follow-up after macular hole surgery was 91.0 months (range, 60.0 to 114.8 months). The hole reopened in 9 eyes (12%) during the follow-up interval; 6 of these eyes underwent reoperation, and the hole closed in 4 of 6 (67%). Preoperative visual acuity ranged from 20/50 to 20/400 (mean, 20/129; median, 20/100). In the 62 eyes that underwent cataract extraction (CE) after macular hole surgery, CE was performed at a median of 13.9 months after macular hole surgery. Patients achieved their best postoperative visual acuity at a median of 28.5 months after macular hole surgery. Best postoperative visual acuity ranged from 20/20 to 20/400 (mean, 20/36; median, 20/30). Visual acuity at last follow-up ranged from 20/25 to counting fingers (mean, 20/56; median, 20/40). At last follow-up, 43 eyes (58%) had a visual acuity of 20/40 or better, and 57 (77%) had an improvement in visual acuity of 3 or more Snellen lines compared with their preoperative acuity. CONCLUSIONS Macular hole closure and visual acuity improvement after initially successful macular hole surgery persist at follow-up of 5 years and longer in the majority of patients; delayed visual acuity improvement is not attributable to cataract surgery alone.

Reopening of macular holes after initially successful repair

OBJECTIVE To evaluate the frequency and prognosis of reopening of a macular hole after initially successful repair in a defined patient cohort. DESIGN Retrospective consecutive noncomparative case series. PARTICIPANTS Seventeen cases of reopened macular holes among 390 cases of idiopathic macular holes that previously had undergone macular hole surgery were studied. MAIN OUTCOME MEASURES Assessment of demographics, visual acuity, preoperatively, postoperatively, after reopening of macular hole and after reoperation, if applicable, and precipitating factors. RESULTS There were 17 (4.8%) of 353 cases in which the macular hole reopened after initial successful surgical closure. The mean visual acuity before reopening was 20/48 and was 20/133 after reopening. Twelve eyes underwent reoperation with improvement to a mean visual acuity of 20/54. The five eyes that were not reoperated on maintained a mean visual acuity of 20/200. Ten of the eyes had undergone cataract surgery between macular hole surgeries, but in only one did the reopening appear to occur in association with this procedure. CONCLUSIONS Reopening of a previously successfully operated macular hole is uncommon and seems to be a spontaneous event. Reoperation generally yields results similar to those present before the reopening. Reopening of a macular hole associated with cataract surgery is rare.

Vitrectomy in the Management of Diabetic Retinopathy

According to the Early Treatment Diabetic Retinopathy Study, at least 5% of eyes receiving optimal medical treatment will still have progressive retinopathy that requires laser treatment and pars plana vitrectomy. During the past decade, improvements in instrumentation and surgical techniques have allowed more difficult cases of diabetic retinopathy to be candidates for vitrectomy. However, although the thresholds for performing surgery within established indicated situations have been lowered, only a few additional indications have been established. Although vitrectomy improves the prognosis for a favorable visual outcome, preventive measures, such as improved control of glucose levels and timely application of panretinal photocoagulation, produce better results. The authors review the indications, techniques, and results of vitrectomy in the management of diabetic retinopathy.

Vitrectomy in the management of diabetic eye disease

Vitrectomy techniques including endolaser photocoagulation allow visual rehabilitation in many eyes that are otherwise untreatable. Discerning the indications and timing for diabetic vitrectomy is increasingly important as the treatment of complications of diabetic retinopathy continues to undergo modification and redefinition. The most common indications for diabetic vitrectomy include: 1) severe nonclearing vitreous hemorrhage; 2) traction retinal detachment recently involving the macula; 3) combined traction and rhegmatogenous detachment; 4) progressive fibrovascular proliferation; and 5) rubeosis iridis and vitreous hemorrhage for eyes in which the media opacity has prevented adequate laser photocoagulation. Other less common indications in selected cases include dense premacular hemorrhage, ghost cell glaucoma, macular edema with premacular traction, cataract preventing treatment of severe, proliferative diabetic retinopathy, anterior hyaloidal fibrovascular proliferation, and fibrinoid syndrome with retinal detachment. The rationale and surgical objectives are discussed and results are summarized.

Clinical features and outcomes of pars plana vitrectomy in patients with retained lens fragments

PURPOSE To investigate the clinical features, visual acuity outcomes, and adverse events in patients with retained lens fragments managed by pars plana vitrectomy (PPV). DESIGN Retrospective, noncomparative, consecutive case series. METHODS Medical records of all patients who underwent PPV for retained lens fragments at Bascom Palmer Eye Institute during the 12-year interval between January 1, 1990, and December 31, 2001, were reviewed. RESULTS The study included 343 eyes of 343 patients, with a median age of 76 years and a median follow-up after PPV of 8 months. The median interval between cataract surgery and PPV was 12 days. Visual acuity was >or=20/40 in 29 (9%) patients preoperatively and 190 (56%) at last follow-up (P < 0.001). Visual acuity was <or=20/200 in 224 (66%) patients preoperatively and 67 (20%) at last follow-up (P < 0.001). An intraocular pressure (IOP) >or=30 mmHg was present in 87 (25%) eyes preoperatively and 7 (2%) at last follow-up (P < 0.001); the number of patients on antiglaucoma medications at these two time points was 135 (40%) and 96 (29%), respectively (P = 0.001). Among the 148 (44%) patients with final vision <20/40, the primary cause of visual impairment was cystoid macular edema (CME) in 41 (29%), preexisting ocular disease in 34 (24%), corneal edema in 22 (15%), history of retinal detachment (RD) in 19 (13%), epiretinal membrane in 6 (4%), and other causes in 21 (15%). Significant predictors of better final visual acuity include better presenting visual acuity (P < 0.001), presence of an intraocular lens (i.e., no aphakia) before PPV (P = 0.026), no suprachoroidal hemorrhage (P = 0.010), no serous choroidal detachment (P = 0.037), no RD (P = 0.005), no CME (P = 0.038), and no additional surgery after the PPV (P < 0.001). Timing of PPV (i.e., <or=1 week versus >1 to <or=4 weeks versus >4 to <or=12 weeks versus >12 weeks between cataract surgery and PPV) was not significantly associated with final visual acuity or IOP outcome; there was also no significant difference in acuity or IOP outcome between patients who underwent PPV on the same day as cataract surgery compared with all other patients. CONCLUSIONS The most important predictor of final visual acuity after PPV for retained lens fragments is a less complicated clinical course (e.g., no suprachoroidal hemorrhage, no RD, no CME, and no additional surgery after PPV). The most common cause of decreased final vision was CME.