Initial experience using the transconjunctival sutureless vitrectomy system for vitreoretinal surgery

OBJECTIVE

To describe the initial experience and to evaluate the safety and feasibility of using the 25-gauge Transconjunctival Sutureless Vitrectomy System (TSV) for a variety of vitreoretinal procedures.

DESIGN

Retrospective review of a consecutive interventional case series.

PARTICIPANTS

Thirty-five eyes of 33 patients, including cases of idiopathic epiretinal membrane (12 cases), retinal detachment (6 cases), macular hole (5 cases), branch retinal vein occlusion (4 cases), retinopathy of prematurity (4 cases), persistent diabetic macular edema (1 case), diabetic vitreous hemorrhage (1 case), retained lens material after cataract extraction (1 case), and Norrie disease (1 case).

INTERVENTION

All patients underwent surgery using the 25-gauge TSV.

MAIN OUTCOME MEASURES

Intraocular pressure, visual acuity, and postoperative complications.

RESULTS

The median preoperative intraocular pressure was 16 mmHg (range, 10-21 mmHg), whereas the median intraocular pressure on the first postoperative day was 12 mmHg (range, 6-28 mmHg). The median intraocular pressure at 1 week and 1 month were both 16 mmHg (range, 10-30 mmHg). Overall, the median preoperative visual acuity was 20/100 (range, 20/30 to hand motions), and the median postoperative visual acuity after a mean follow-up of 14 weeks (range, 1-60 weeks) was 20/60 (range, 20/20-20/150). One eye developed a postoperative retinal detachment.

CONCLUSIONS

The 25-gauge TSV seems to be practical and safe for a variety of vitreoretinal procedures. The concept of transconjunctival surgery has the potential to increase the efficiency of a variety of vitreoretinal surgeries and possibly hasten the postoperative recovery and outcomes in several conditions by simplifying the surgical procedure; minimizing surgically induced trauma; and decreasing the convalescence period, the operating time, and the postoperative inflammatory response.

Adjuvant 5-fluorouracil and heparin prevents proliferative vitreoretinopathy : Results from a randomized, double-blind, controlled clinical trial

PURPOSE

To assess the safety and efficacy of adjuvant combination therapy using 5-fluorouracil (5-FU) and low molecular weight heparin (LMWH) for prevention of proliferative vitreoretinopathy (PVR) after vitrectomy and retinal reattachment surgery.

DESIGN

Prospective randomized, double-masked, placebo controlled trial.

PARTICIPANTS

One hundred seventy-four high-risk patients were randomized to receive either 5-FU and LMWH therapy or placebo. Patients were selected from all patients undergoing primary vitrectomy for rhegmatogenous retinal detachment.

METHOD

Results of standard surgery with 5-FU and LMWH therapy or placebo were compared at the 6-month follow-up.

MAIN OUTCOME MEASURES

Development of postoperative PVR, retinal reattachment at 6 months after surgery, single operation reattachment rate, number of reoperations, and best-corrected visual acuity.

RESULTS

There were 87 patients in the 5-FU and LMWH therapy group and 87 in the placebo group. The incidence of postoperative PVR was significantly lower (P = 0.02) in the 5-FU and LMWH therapy compared with the placebo group. In 26.4% (23/87) of the placebo group and in 12.6% (11/87) of the 5-FU and LMWH group, postoperative PVR developed. In the 5-FU and LMWH group, the number of patients undergoing more than one operation was 19.5% (17/87) and the number of reoperations resulting from PVR was 52.9% (9/17). In the placebo group, the number of patients undergoing more than one operation was 25.3% (22/87) and the number of reoperations resulting from PVR was 72.7% (16/22). The difference in visual acuity was not statistically different in the two treatment groups, although those patients in whom postoperative PVR developed tended to have poorer vision (P < 0.0001). There were no differences in complication rates between the two groups.

CONCLUSIONS

There is a significant reduction in the incidence of postoperative PVR in patients receiving the 5-FU and LMWH therapy and in the reoperation rate resulting from PVR. This trial shows that incidence of PVR can be reduced with inexpensive and simple pharmacologic treatment with 5-FU and LMWH and should be used routinely in the treatment of patients at risk of developing PVR.

Macular changes after peeling of the internal limiting membrane in macular hole surgery

PURPOSE

To report the incidence of macular changes following pars plana vitrectomy with peeling of the internal limiting membrane (ILM) for idiopathic macular hole.

DESIGN

Prospective consecutive series.

METHODS

In a prospective study 105 eyes of 105 patients underwent vitrectomy for idiopathic macular holes. Surgery consisted of a standard three-port vitrectomy, induction of a posterior hyaloid detachment, removal of epiretinal membranes including the ILM, fluid-air exchange and intraocular gas tamponade (15% hexafluoroethane (C2F6) gas mixture) followed by head-down positioning for at least five days. No adjuvants were used during surgery. In addition to the clinical examination, static microperimetry using a Rodenstock scanning laser ophthalmoscope (SLO-105) was performed pre- and 6 or 12 weeks postoperatively. The stimulus size was 0.2 degrees (Goldmann II), intensities employed were 0 and 12 dB. For all tests, 20-degree fields were used.

RESULTS

Anatomic closure of macular holes was achieved in 92 (87.6%) of 105 patients by one operation. Eight patients underwent a successful second procedure. The closure rate after two operations was 95.2%. Best corrected visual acuity increased from a median of 0.2 (range 0.05 to 0.5) preoperatively to a median of 0.5 (range 0.05 to 1.0) postoperatively. Anatomical macular changes were found in 8 (7.6%) patients: There were two cases of macular edema following secondary cataract extraction and six cases of retinal pigment epithelium changes. Formation of postoperative epiretinal membranes or late reopenings were not noted. Small, mostly asymptomatic paracentral scotomata were seen in 59 (56.2%) of 105 patients.

CONCLUSION

Anatomical changes of the macula following vitrectomy with removal of the ILM are infrequent. However, paracentral scotomata observed in our series might be caused by a trauma to the nerve fibers during ILM peeling. To achieve reliable results a standardized procedure for microperimetry should be developed.

Nuclear sclerotic cataract after vitrectomy for idiopathic epiretinal membranes causing macular pucker

We evaluated the occurrence or progression of nuclear sclerosis of the crystalline lens in 100 eyes after vitrectomy for removal of idiopathic epiretinal membranes causing macular pucker. The follow-up period ranged from six to 99 months (average, 29 months). Visually significant nuclear sclerosis was present preoperatively in three of the operated on eyes and four of the fellow eyes. The rate of occurrence or progression of visually significant nuclear sclerosis was far greater in the operated on eyes (P less than .0001). Of 100 patients, 80 operated on eyes and 24 fellow eyes had visually significant nuclear sclerosis or had undergone previous cataract extraction at the conclusion of the study. Different concentrations of glucose in the intraocular irrigating solution did not affect occurrence of later nuclear sclerosis. Patients older than 50 years of age had a far greater incidence of later nuclear sclerosis than patients younger than 50 years of age (P = .0003). Nuclear sclerosis may be caused by altered lens metabolism after removal of part of the vitreous gel, since nuclear sclerosis also occurs in other conditions associated with vitreous liquefaction.

Vitrectomy for macular pucker

Vitreous surgery was used to treat 130 consecutive cases with epiretinal membranes causing macular pucker. The membrane: (1) occurred after otherwise successful retinal reattachment surgery in 78 eyes (60%), (2) was idiopathic in 28 eyes (22%), (3) was associated with other ocular disorders in 20 eyes (15%), and (4) in four eyes may have been developmental. The abnormal tissue was successfully removed in 128 of 130 eyes, and vision improved at least two lines on the Snellen chart in 108 eyes (83%). Postoperative visual acuity was 20/20 in five eyes (4%), 20/25 to 20/40 in 41 eyes (31.5%), 20/50 to 20/100 in 64 eyes (49%), 20/200 in 15 eyes (11.5%), and 20/400 in five eyes (4%). Complications included one case of sterile endophthalmitis and one case of infective endophthalmitis (Staphylococcus epidermidis). Peripheral retinal tears occurred in six eyes (5%). No posterior retinal breaks occurred in this series. Later retinal detachment occurred in eight eyes (6%) requiring further retinal surgery. Progressive postoperative nuclear sclerotic lens changes occurred in 31 (34%) of 90 phakic eyes. Sizable amounts of epiretinal tissue recurred postoperatively in four eyes (3%).

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.

Progression of nuclear sclerosis and long-term visual results of vitrectomy with transforming growth factor beta-2 for macular holes

PURPOSE

We studied the progression of cataracts and visual acuity up to 36 months after vitrectomy and instillation of transforming growth factor beta-2 for treatment of full-thickness macular holes.

METHODS

Sixty-four eyes with idiopathic and two with traumatic macular holes in this prospective consecutive series were divided into the following two groups: 56 phakic eyes were treated with 70, 330, or 1,330 ng of transforming growth factor beta-2 to study the progression of cataracts, and 31 phakic or pseudophakic eyes were treated with 1,330 ng of transforming growth factor beta-2 to study the long-term visual acuity after macular hole surgery.

RESULTS

Eyes in the cataract progression study had a mean preoperative nuclear sclerosis grade of 0.4, which increased to 2.4 on final lens examination at a mean of 12.4 months postoperatively. The amount of nuclear sclerosis increased progressively with duration of follow-up, and 16 (76%) of 21 eyes followed up for 24 months or more required cataract extraction. The mean preoperative posterior subcapsular cataract grade was 0.0 and increased only slightly to 0.25 on final lens examination. All eyes had initial successful closure of the macular hole, but the macular hole reopened in two eyes (between six and 12 months and at 19 months) for an overall success rate of 29 (93.5%) of 31 eyes at a mean of 19.5 months. The visual acuity increased two or more Snellen lines in 29 (93.5%) of 31 eyes. The final visual acuity was 20/40 or better in 23 (74%) of 31 eyes and the visual improvement was stable in eyes followed up for three years.

CONCLUSIONS

Nuclear sclerotic cataracts progress substantially after macular hole surgery with a long-acting intraocular gas tamponade. The visual acuity often decreases 12 or more months after vitrectomy because of cataract progression, but the visual results of vitrectomy and transforming growth factor beta-2 for macular holes are excellent when the cataracts are removed.

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%).

Early vitrectomy for severe proliferative diabetic retinopathy in eyes with useful vision. Results of a randomized trial--Diabetic Retinopathy Vitrectomy Study Report 3. The Diabetic Retinopathy Vitrectomy Study Research Group

Three hundred seventy eyes with advanced, active, proliferative diabetic retinopathy (PDR) and visual acuity of 10/200 or better were randomly assigned to either early vitrectomy or conventional management. After 4 years of follow-up, the percentage of eyes with a visual acuity of 10/20 or better was 44% in the early vitrectomy group and 28% in the conventional management group. The proportion with very poor visual outcome was similar in the two groups. The advantage of early vitrectomy tended to increase with increasing severity of new vessels. In the group with the least severe new vessels, no advantage of early vitrectomy was apparent.

Posterior segment complications after vitrectomy for macular hole

PURPOSE

The purpose of this study is to assess the rate of posterior segment complications after vitreous surgery for macular holes and to evaluate the effect of such complications on final visual outcome.

METHODS

The authors reviewed retrospectively all cases of vitreous surgery for macular holes performed between June 1990 and October 1993. Among 98 patients with a followup of 3 months or more, all patients with posterior segment complications during the postoperative course were identified. The rate of complications was compared with that seen after vitreous surgery for macular pucker performed by the same surgeons.

RESULTS

Posterior segment complications were noted in 23 (23%) of 98 patients. These included peripheral retinal breaks (3%), rhegmatogenous retinal detachment from a peripheral retinal break (14%), enlargement of the hole (2%), late reopening of the hole (2%), retinal pigment epithelium loss under the hole (1%), photic toxicity (1%), and endophthalmitis (1%). In 40% of these eyes, the final visual acuity was two lines or more below preoperative visual acuity. When compared with the macular pucker group, the rate of posterior segment complications, in particular the rate of peripheral retinal tears and detachments, was significantly higher (P < or = 0.05).

CONCLUSIONS

The authors conclude that visually significant posterior segment complications may occur after vitrectomy for macular hole, and the rate of these complications appears to be higher than expected.

Internal Limiting Membrane Removal during Macular Hole Surgery

PURPOSE

To evaluate the effect of internal limiting membrane (ILM) peeling and other variables in hole closure and functional success rate after idiopathic macular hole surgery.

DESIGN

Retrospective, multicenter, observational study.

METHODS

The records of 1627 patients operated on for idiopathic macular hole were collected retrospectively from 28 surgeons. All patients underwent a single pars plana vitrectomy and were divided into 2 groups: with and without ILM peeling. Preoperative, intraoperative, and postoperative variables were evaluated.

RESULTS

The overall rate of macular hole closure was 94.1% in the ILM peeling group and 89.0% in the no ILM peeling group (P<0.001). The probability of achieving hole closure after surgery is 2.59 times higher if the ILM is peeled (95% confidence interval [CI], 1.71-3.92; P<0.001), 3.12 times higher for holes lasting less than 6 months (95% CI, 1.70-5.71; P<0.001), 4.94 (95% CI, 2.39-10.20) for stage 2 holes, and 2.34 (95% CI, 1.55-3.53) for stage 3 holes than that of patients with a stage 4 hole (P<0.001).

CONCLUSIONS

Internal limiting membrane peeling seems to improve hole closure for stage 3 and 4 holes and for long-lasting holes. Higher-stage macular holes and longer duration of symptoms are risk factors for surgical failure. In patients obtaining hole closure, there is no difference in functional results between pseudophakic peeled and not peeled patients, whereas in phakic patients, a better functional result in not peeled patients was seen.

Intravitreal silicone oil injection: complications and treatment of 415 consecutive patients

Silicone oil injection in conjunction with pars plana vitrectomy was carried out by five surgeons in 415 consecutive patients using the same surgical equipment, the same surgical techniques and the same highly purified silicone oil (viscosity, 5000 mPa.s). Indications for silicone oil injection after vitrectomy included advanced stages of proliferative vitreoretinopathy following rhegmatogenous retinal detachment (49%), severe proliferative diabetic retinopathy (38%), and proliferative vitreoretinopathy following retinal detachment due to ocular trauma (13%). Postoperative complications were noted in a 6- to 30-month follow-up period. Cataractous changes of varying degree were seen in all phakic eyes. Silicone oil entered the anterior chamber in 6% of all phakic and pseudophakic eyes. Subretinal silicone oil was noted in 4%. Other complications associated with the use of intravitreal silicone oil included biomicroscopically visible silicone oil emulsification (0.7%), keratopathy (5.5%), glaucoma (6%), closure of the inferior iridectomy (6%), and reproliferation of epiretinal and subretinal fibrous membranes (40%). We anticipate that the physico-chemical characteristics of the highly purified silicone oil (viscosity, 5000 mPa.s) and the routine performance of an inferior iridectomy in all aphakic eyes had a positive impact on the low incidence of silicone-oil-related complications such as emulsification, keratopathy and secondary glaucoma.

Risk factors of corneal graft failure

PURPOSE

To measure the association between potential risk factors and corneal graft failure. Two failure outcomes are compared: those with and those without a prior immune allograft reaction.

METHODS

Based on a single-center observational study design, 539 adult recipients of a corneal graft were followed for a median time of 30 months. Survival analysis was carried out.

RESULTS

Eighty-two graft failures were recorded. Of 82 failures, 53 (65%) were not preceded by an immune allograft reaction. Presence of blood vessels in the recipient cornea was associated with a twofold increase in risk for both failure outcomes. Three factors increased the risk of failure without an immune reaction: prior glaucoma or uveitis (adjusted relative risk estimate = 3.1), vitreous surgery with the graft (adjusted relative risk estimate = 2.0), and a repeat graft in the study eye (adjusted relative risk estimate = 2.0). Conversely, large graft wound size (adjusted relative risk estimate = 2.0). Conversely, large graft wound size (adjusted relative risk estimate = 2.9) and human leukocyte antigen (HLA)-A, -B incompatibility (adjusted relative risk estimate = 2.2) were associated with failures that followed an immune reaction.

CONCLUSION

In this study, the authors support the clinical impression that corneal graft failures with and without a prior immune reaction are distinct phenomena. Enhanced surveillance in recipients with glaucoma and early intensive treatment of allograft reactions are recommended to improve the outcome of corneal grafts.

Glaucoma after pediatric lensectomy/vitrectomy

Glaucoma after pediatric cataract surgery, once well recognized, now occurs only rarely after modern lensectomy/vitrectomy. The authors performed directed glaucoma evaluations of 34 eyes of 26 children. Based on intraocular pressures of 26 mmHg or greater, glaucoma was diagnosed in 8 (24%) eyes of 7 (27%) children. Glaucoma was found more commonly among children followed more than 60 months and was diagnosed up to 105 months after surgery. Typically, the glaucoma was open angle and asymptomatic. Four children had had previously normal pressures recorded. With longer follow-up, it is likely that more children will be diagnosed with glaucoma after lensectomy/vitrectomy procedures. The authors believe such patients should be followed as glaucoma suspects for the rest of their lives.

Endophthalmitis after pars plana vitrectomy. The Postvitrectomy Endophthalmitis Study Group

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% (5/7) of eyes infected with coagulase-negative 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.

Macular hole surgery without face-down positioning. A pilot study

PURPOSE

To investigate whether postoperative face-down positioning is necessary for successful macular hole repair.

BACKGROUND

Although never proven, face-down positioning is strongly considered an important maneuver to achieve macular hole closure. Face-down posturing is inconvenient, and for patients with physical or mental limitations, weeks of face-down positioning may be an impossible task. A gas bubble that completely fills the vitreous cavity will tamponade a macular hole despite head position and may close a macular hole as effectively as a partial gas fill with face-down positioning. If face-down positioning were not necessary, more patients would be eligible to benefit from this surgery.

METHODS

Thirty-three consecutive eyes in 31 patients aged 65-79 years with Stage II, III, or IV full-thickness macular holes underwent macular hole surgery with a complete 15% C3F8 vitreous fill. Hole duration varied from 1 month to 10 years; in 21% of eyes, (seven of 33) holes had been present for more than 1 year. All phakic eyes (n = 25) had cataract extraction with intraocular lens insertion when macular hole surgery was done. No patients were positioned face down.

RESULTS

The follow-up period was 6-40 months; 73% of the patients have been observed for more than 1 year. Preoperative hole duration did not affect hole closure rate. The success rate after one surgery was 79% (26 of 33 eyes), and with additional vitrectomy surgery, the total success rate was 85% (28 of 33 eyes). Forty-eight percent of eyes attained visual acuity of 20/50. Eighty percent of eyes with preoperative acuity of > 20/100 attained > 20/50 acuity. Significant complications included iris incarceration into the cataract wound during a postoperative fluid-gas exchange (one eye), posterior synechiae (four eyes), intraocular lens capture (two eyes), elevated intraocular pressure (three eyes), and retinal detachment (three eyes). Most of these problems can be avoided or reduced.

CONCLUSION

This pilot study suggests that successful macular hole closure is possible without face-down positioning. This technique may be an alternative for patients with macular holes in pseudophakic eyes who are unable to assume face-down posturing. Combining cataract surgery with this technique for macular hole repair is reasonable for phakic patients who cannot maintain prone positioning. Major disadvantages of combined surgery include the morbidity of the second procedure and removal of a visually insignificant cataract. This approach should be considered for those patients unable to tolerate face-down positioning.

Vision-threatening complications of surgery for full-thickness macular holes. Vitrectomy for Macular Hole Study Group

OBJECTIVE

To study complications of vitrectomy surgery for full-thickness macular holes.

DESIGN

A multicentered, randomized, controlled clinical trial.

PARTICIPANTS

Community and university-based ophthalmology clinics.

INTERVENTION

Standardized macular hole surgery versus observation.

MAIN OUTCOME MEASURES

Assessment of anatomic and visual outcomes and determination of postoperative complications at 12 months after randomization.

RESULTS

Posterior segment complications were noted in 39 eyes (41%). The incidence of retinal pigment epithelium (RPE) alteration and retinal detachment (RD) were 33% and 11%, respectively. One RD due to a giant retinal tear resulted in a visual acuity of light perception. Other complications included a reopening of the macular hole in 2 eyes (2%), cystoid macular edema in 1 eye (1%), a choroidal neovascular membrane in 1 eye (1%) and endophthalmitis in 1 eye (1%). Eyes with complications had significantly worse visual acuity outcomes as determined by the Early Treatment Diabetic Retinopathy Study, Word Reading, and Potential Acuity Meter charts (P < 0.01 for all comparisons). Eyes with macular holes greater than 475 microns were more than twice as likely to have complications than eyes with holes less than 475 microns (odds ratio [OR] = 2.2, P = 0.07). Before surgery, the stage of the hole was related to postoperative RPE changes (P < 0.0001) and the occurrence of postoperative RD (P = 0.0002). Intraoperative trauma was related to the occurrence of these complications (P < 0.0001 for RPE changes, P = 0.02 for RDs). Epiretinal membrane removal was related to RPE changes (P = 0.02) but not RDs.

CONCLUSIONS

The RPE alterations and RDs are common after macular hole surgery and result in significantly reduced postoperative visual acuity. The RPE changes may be related to surgical trauma or light toxicity. Further efforts to reduce complications associated with macular hole surgery are indicated.

Outcomes of Vitrectomy with Inferior Retinectomy in Patients with Recurrent Rhegmatogenous Retinal Detachments and Proliferative Vitreoretinopathy

PURPOSE

To report the anatomic and functional outcomes of patients treated with vitrectomy and inferior retinectomy for recurrent, rhegmatogenous retinal detachment complicated by proliferative vitreoretinopathy (PVR).

DESIGN

Retrospective, noncomparative, interventional case series.

PARTICIPANTS

Fifty-six patients with recurrent, rhegmatogenous retinal detachments complicated by PVR who underwent an inferior retinectomy for repair.

METHODS

Retrospective review over a 6-year period of patients treated with vitrectomy and inferior retinectomy.

MAIN OUTCOME MEASURES

The primary outcome was anatomic success, defined as complete retinal reattachment. Secondary outcomes included change in visual acuity, the mean number of operations required for complete retinal reattachment, number of operations before retinectomy, use of silicone oil tamponade, location and extent of retinectomy, whether lensectomy was undertaken, and incidence of postoperative complications.

RESULTS

Complete retinal reattachment was achieved in 52 of 56 patients (93%), with a mean follow-up of 25 months (range, 6-70 months). After retinal reattachment, visual acuity was improved or stabilized in 39 of 56 patients (70%). The mean number of operations for retinal detachment before diagnosis of PVR requiring retinectomy was 1.8 (range, 1-5). Patients undergoing radical anterior vitreous base dissection and lensectomy at the time of first retinectomy had a higher success rate than those who did not: 74% versus 38%, respectively (P = 0.011). Furthermore, tamponade with silicone oil had a higher success rate than tamponade with gas: 71% versus 18%, respectively (P = 0.002). Of the 56 patients, 9 (16%) had 1 or more of the following complications: keratopathy requiring penetrating keratoplasty (n = 4), glaucoma requiring aqueous shunt device (n = 3), and hypotony (n = 3). Silicone oil removal was performed in 26 of 45 patients (58%) before the last follow-up visit, with a 1 in 26 (4%) redetachment rate.

CONCLUSIONS

When combined with anterior base dissection, inferior retinectomy may be useful in the surgical treatment of complex PVR-related retinal detachment. The authors show that with lensectomy, radical anterior base dissection, and inferior retinectomy, anatomic success rates are improved and visual function can be maintained. In addition, silicone oil offers an advantage over gas tamponade in these cases.

Endophthalmitis after pars plana vitrectomy: Incidence, causative organisms, and visual acuity outcomes

PURPOSE

To investigate the incidence, causative organisms, and visual acuity outcomes associated with endophthalmitis after pars plana vitrectomy.

DESIGN

Retrospective, noncomparative, consecutive case series.

METHODS

The medical records were reviewed of all patients who developed acute-onset postoperative endophthalmitis (within 6 weeks of surgery) after pars plana vitrectomy at Bascom Palmer Eye Institute between January 1, 1984 and December 31, 2003.

RESULTS

During the 20-year study interval, the overall incidence rate of postvitrectomy endophthalmitis was 0.039% (6/15,326). Cultured organisms were Staphylococcus aureus (n = 3), Proteus mirabilus (n = 1), and Staphylococcus epidermidis/Pseudomonas aeruginosa (n = 1); one case was culture-negative. Visual acuity after treatment for endophthalmitis ranged from 2/200 to no light perception, with a final vision of light perception or no light perception in four of six (67%) eyes.

CONCLUSION

The incidence of endophthalmitis after pars plana vitrectomy is low but the visual acuity outcomes after treatment are generally poor.

25-gauge vs 20-gauge system for pars plana vitrectomy: a prospective randomised clinical trial

AIM

To compare 25-gauge vs 20-gauge system for pars plana vitrectomy in a prospective, randomised, controlled clinical trial.

METHODS

Three-port pars plana vitrectomy was performed in 60 patients belonging to 2 groups. Evaluations were performed preoperatively, intraoperatively, during the first three postoperative days, at 1 week, and at 1 and 3 months. The main outcome measure was time for surgery, divided into duration of wound opening, vitrectomy, retinal manipulation and wound closure.

RESULTS

The total duration of surgery showed no significant difference between the groups (p = 0.67). The 25-gauge group showed significantly shorter duration of wound opening (p<0.001) and wound closure (p<0.001). In contrast, the vitrectomy duration was significantly longer in the 25-gauge group (p<0.001). Conjunctival injection and subjective postoperative pain showed significantly lower irritation in the 25-gauge group (p<0.001 for both).

CONCLUSION

The 25-gauge vitrectomy system offered significantly improved patient comfort during the first postoperative week. The smaller surgical openings facilitated wound healing and minimised pain. Duration of surgery was comparable between the two systems-the shorter time needed for wound opening and closure in the 25-gauge group being equalised by the longer vitrectomy duration. Intraoperative as well as retinal manipulation and illumination caused more surgical difficulties using the 25-gauge system.

Pars plana vitrectomy versus combined pars plana vitrectomy-scleral buckle for primary repair of pseudophakic retinal detachment

PURPOSE

To evaluate pars plana vitrectomy (PPV) versus a combined PPV and scleral buckle (PPV/SB) for repair of noncomplex, pseudophakic retinal detachment.

DESIGN

Retrospective, nonrandomized, comparative interventional study.

PARTICIPANTS

One hundred fifty-two eyes of 152 patients followed up for a mean of 10 months. The case series included 68 consecutive patients who underwent PPV and 84 consecutive patients who underwent a PPV/SB for primary repair of primary pseudophakic retinal detachment at Wills Eye Hospital between 2002 and 2004.

METHODS

All primary PPV cases were performed by 2 surgeons who perform primary vitrectomy without regard to location of detachment, number and location of break(s), refractive error, or macula status. All primary PPV/SB were performed by a group of surgeons who solely perform PPV/SB on pseudophakic retinal detachments. All eyes underwent a standard 3-port 20-gauge PPV under wide-field viewing and scleral depression. Endolaser photocoagulation was applied either around the retinal tears or 360 degrees to the vitreous base region followed by gas tamponade. Patients with proliferative vitreoretinopathy grade C or worse were excluded from the study.

MAIN OUTCOME MEASURES

(1) Single surgery anatomic success rates, (2) preoperative and postoperative visual acuity, and (3) complications.

RESULTS

The single surgery anatomic success rate in the primary PPV group was 63 of 68 eyes (92.6%; 95% confidence interval [CI], 84%-98%) and in the primary PPV/SB group was 79 of 84 eyes (94.0%; 95% CI, 87%-98%). Both groups obtained 100% final reattachment rate. There was no statistically significant difference between the success rates (P = 0.75, Fisher exact test). The PPV group's best-corrected postoperative visual acuity demonstrated a +0.10 logarithm of the minimum angle of resolution improvement over the PPV/SB group (P = 0.07). The PPV group had a smaller incidence of postoperative complications (13/68 patients [19.1%] vs. 27/84 patients [32.1%]; P = 0.10, Fisher exact test).

CONCLUSIONS

Primary PPV and PPV/SB seem to have similar efficacy in the repair of a matched group of patients with primary noncomplex pseudophakic retinal detachment. There was no statistically significant difference in complication rate between the 2 groups.

Posterior subcapsular and nuclear cataract after vitrectomy

PURPOSE

To examine the morphological changes in the postvitrectomy lens and to monitor the development of these changes over time.

SETTING

Oxford Eye Hospital, Oxford, United Kingdom.

METHODS

In this prospective study, 33 consecutive phakic patients having pars plana vitrectomy were recruited. Cataract development was quantified by clinical grading and digital Scheimpflug image analysis. Slitlamp biomicroscopy and photography were used to document the morphological appearance. The main outcome measures were the incidence, morphology, and development of posterior subcapsular and nuclear cataract.

RESULTS

A characteristic, transient posterior subcapsular cataract (PSC) was present in 89% (17 of 19) of tamponade patients within 24 hours of surgery. Of the patients who had vitrectomy without tamponade, 9% (1 of 11) developed similar changes. Nuclear opacity developed in 61% (11 of 18) of tamponade patients and in 50% (3 of 6) of nontamponade patients. A longer term retrospective review of the same patients' case notes revealed nuclear cataract in 67% (12 of 18) of tamponade cases and 30% (3 of 10) of nontamponade cases. Eighteen percent (2 of 11) of nontamponade cases and 67% (14 of 21) of tamponade cases had cataract surgery after a 10.7 month and a 12.4 month follow-up, respectively.

CONCLUSIONS

Vitrectomy and tamponade produced a characteristic transient PSC in the immediate postoperative period. Disruption of fluid balance in the region of the posterior lens was suggested by the morphological appearance. The acute changes resolved but were followed by accelerated nuclear opacification.

Glaucoma after pars plana vitrectomy and silicone oil injection for complicated retinal detachments

OBJECTIVE

To determine the incidence and associations of glaucoma after pars plana vitrectomy (PPV) and silicone oil injection (SOI) for complicated retinal detachments and the response to treatment.

DESIGN

Retrospective noncomparative case series.

PARTICIPANTS

A total of 150 eyes of 150 patients who had completed a minimum of 6 months of follow-up were included in this study. Analysis included clinical records of all consecutive cases of complicated retinal detachment that underwent PPV with SOI between July 1991 and February 1996.

INTERVENTION

Surgical intervention for vitreoretinal pathology included standard three-port PPV and additional procedures as appropriate for the retinal pathology, and SOI. Procedures for the control of glaucoma were silicone oil removal (SOR), trabeculectomy with mitomycin C, cyclocryotherapy, semiconductor diode laser contact transscleral cyclophotocoagulation (TSCPC) and anterior chamber tube shunt to encircling band (ACTSEB).

MAIN OUTCOME MEASURES

Presence of glaucoma (predefined as intraocular pressure [IOP] > or = 24 mmHg, which also was > or = 10 mmHg over the preoperative level, sustained for > or = 6 weeks) and the result of medical and surgical management were the main outcome measures. Demographic, preoperative, intraoperative, and postoperative parameters including the age of the patient, etiology of retinal detachment, refractive status, pre-existing glaucoma, aphakia, diabetes mellitus, presence of silicone oil (SO) in the anterior chamber, emulsification of SO, rubeosis iridis, and anatomic success were evaluated by univariate and multivariate logistic regression analyses to assess their predictive value in the causation of glaucoma and to determine factors prognosticating response to treatment.

RESULTS

The main indications for PPV+SOI were proliferative vitreoretinopathy (57%; 85 of 150), proliferative diabetic retinopathy (15%; 23 of 150), and trauma (14%, 21 of 150). Glaucoma occurred in 60 eyes (40%) at 14 days median (range, 1 day-18 months). Elevation of IOP could be attributed directly to SO in 42 (70%) eyes. Glaucoma was controlled in 43 (72%) of 60 eyes on treatment (with medicines alone in 30%; SOR and medicines in 25%; trabeculectomy with mitomycin C/ACTSEB/cyclocryotherapy or TSCPC in 17%); 28% (17 of 60) remained refractory. Independent predictive factors for glaucoma on multivariate analysis were rubeosis iridis (odds ratio, 10.76), aphakia (odds ratio, 9.83), diabetes (odds ratio, 6.03), SO in anterior chamber (odds ratio, 4.74), and anatomic failure (negative risk factor; odds ratio, 0.11). Poor prognostic factors for the control of glaucoma were SO emulsification (odds ratio, 15.34) and diabetes (odds ratio, 6.03).

CONCLUSION

Glaucoma is a frequent and often a refractory complication of PPV with SOI and has a multifactorial etiology. Aggressive medical and surgical management with SOR, trabeculectomy with mitomycin C, glaucoma shunts, and cyclodestructive procedures shows modest success in controlling IOP.

Postoperative complications associated with 25-gauge pars plana vitrectomy

BACKGROUND AND OBJECTIVE

To report postoperative complications in eyes undergoing 25-gauge pars plana vitrectomy (PPV).

PATIENTS AND METHODS

Seventy consecutive eyes that underwent 25-gauge PPV for various indications, including epiretinal membrane, non-clearing vitreous hemorrhage, and idiopathic macular hole, and had a minimum follow-up of 12 weeks were reviewed retrospectively. Main outcome measures included best-corrected Snellen visual acuity, intraocular pressure (IOP), intraoperative complications, and postoperative complications.

RESULTS

The mean visual acuity improved from 20/368 preoperatively to 20/105 postoperatively (P < .00005). Intraoperative complications included retinal tears in 2 eyes (2.9%). Postoperative complications included cataract progression in 17 eyes (42.5%), cystoid macular edema exacerbation in 5 eyes (7.1%), and retinal detachment in 1 eye (1.4%). Postoperative day 1 IOP was statistically lower than preoperative IOP in fluid-filled eyes (P = .031) but not in eyes filled with intravitreal air (P = .30) or gas (P = .52). Sclerotomy sutures were required intraoperatively in 5 eyes (7.1%) and postoperative day 1 hypotony was noted in 4 eyes (5.7%). All of these complications were noted in fluid-filled eyes except for one case of postoperative day 1 hypotony with gas tamponade.

CONCLUSIONS

Intraoperative and postoperative complications were rare in this series of 25-gauge PPV. Postoperative cataract progression and hypotony were the most common complications. Fluid-filled eyes appear to have a higher risk of wound leakage and postoperative hypotony after 25-gauge PPV than eyes with air or gas tamponade.

Early postoperative retinal thickness changes and complications after vitrectomy for diabetic macular edema

PURPOSE

To determine the early postoperative changes in retinal thickness and complications after pars plana vitrectomy for diabetic macular edema.

DESIGN

Consecutive interventional case series.

METHODS

Studied retrospectively, pars plana vitrectomy was performed on 65 consecutive eyes of 63 patients with diabetic macular edema. The follow-up interval ranged from 6 to 36 months (12.6 +/- 7.4 months [mean +/- standard deviation (SD)]). The indications of pars plana vitrectomy in this study were (1) diffuse diabetic macular edema, (2) preoperative visual acuity less than 20/40, and (3) noneffective macular photocoagulation therapy. Preoperative and postoperative examinations by stereoscopic biomicroscopy, color fundus photography of the macula and optical coherence tomography (OCT) were performed on all eyes. Preoperatively, direct photocoagulation to microaneurysms in the macula had been performed in 48 eyes, and focal/grid photocoagulation had been performed in five eyes. Preoperative examination showed that epiretinal membranes were observed in 20 eyes, cystoid macular edema in 40 eyes, and 23 eyes had a complete posterior vitreous detachment (PVD). Epimacular membranes, removed during surgery, were examined histopathologically.

RESULTS

The postoperative mean best-corrected visual acuity (logarithm of the minimum angle of resolution [logMAR] = 0.696 +/- 0.491 [mean +/- SD]) was significantly better than the preoperative mean best-corrected visual acuity (0.827 +/- 0.361; P <.0001; Wilcoxon signed-rank test). The final visual acuity improved by 2 or more lines in 32 of 65 eyes (45%), remained unchanged in 32 of 65 eyes (49%), and exacerbated after the surgery in 4 of 65 eyes (6%) due to neovascular glaucoma (2 eyes) and residual cystoid macular edema (2 eyes). The postoperative foveal retinal thickness (224.9 +/- 116.9 microm) at the last visit was significantly thinner than the preoperative foveal retinal thickness (463.7 +/- 177.3 microm; P <.0001; Wilcoxon signed-rank test). The foveal retinal thickness did not decrease linearly but fluctuated: The mean postoperative retinal thickness had decreased significantly 7 days after surgery, then remained unchanged for approximately 1 month, and thereafter gradually decreased until 4 months. The intraoperative and postoperative complications included peripheral retinal tear in 3 of 65 (4.6%) eyes, postoperative rhegmatogenous retinal detachment in 1 of 65 (1.5%) eyes, neovascular glaucoma in 3 of 65 (5%) eyes, recurrent vitreous hemorrhage in 1 of 65 (1.5%) eyes, hard exudates in the center of the macula in 3 of 56 (4.6%) eyes, postoperative epiretinal membrane formation in 9 of 65 (13.8%) eyes, and a lamellar macular hole in 1 of 65 (1.5%) eyes.

CONCLUSIONS

Vitrectomy for diabetic macular edema is an effective procedure for reducing the edema and improving visual acuity. Because the postoperative reduction in retinal thickness is not complete until 4 months, the assessment of vitrectomy on foveal thickness should not be made until this time. In addition, there are severe complications from vitrectomy for diabetic macular edema, and careful preoperative and postoperative examinations and surgical methods are required.