PARS PLANA VITRECTOMY FOR DIABETIC MACULAR EDEMA: A Systematic Review, Meta-Analysis, and Synthesis of Safety Literature.

PURPOSE: To assess the risk and benefit of pars plana vitrectomy for diabetic macular edema. METHODS: The authors conducted a systematic literature review using PubMed, EMBASE, Web of Science, and Cochrane Central Database of Controlled Trials until September 2014. The population was patients with diabetic macular edema, intervention vitrectomy, comparator macular laser or observation, and efficacy outcome visual acuity and central retinal thickness. Safety outcomes were intraoperative and postoperative surgical complications. The efficacy meta-analysis included only randomized controlled trials. The safety analysis included prospective, retrospective, controlled, and uncontrolled studies. RESULTS: Five studies were eligible for the efficacy meta-analysis (n = 127 eyes) and 40 for the safety analysis (n = 1,562 eyes). Combining follow-up intervals from 6 to 12 months, the meta-analysis found a nonsignificant 2 letter visual acuity difference favoring vitrectomy, and a significant 102 µm greater reduction in central retinal thickness favoring vitrectomy, but a post hoc subgroup analysis found that a 6-month central retinal thickness benefit reversed by 12 months. The most frequent complications were retinal break (7.1%), elevated intraocular pressure (5.2%), epiretinal membrane (3.3%), and vitreous hemorrhage (2.4%). Cataract developed in 68.6% of 121 phakic eyes. CONCLUSION: Vitrectomy produces structural and functional improvements in select eyes with diabetic macular edema, but the visual gains are not significantly better than with laser or observation. No major safety concerns were identified.

Direct cost of pars plana vitrectomy for the treatment of macular hole, epiretinal membrane and vitreomacular traction: a bottom-up approach.

PURPOSE: The direct cost to the National Health Service (NHS) in England of pars plana vitrectomy (PPV) is unknown since a bottom-up costing exercise has not been undertaken. Healthcare resource group (HRG) costing relies on a top-down approach. We aimed to quantify the direct cost of intermediate complexity PPV. METHODS: Five NHS vitreoretinal units prospectively recorded all consumables, equipment and staff salaries during PPV undertaken for vitreomacular traction, epiretinal membrane and macular hole. Out-of-surgery costs between admission and discharge were estimated using a representative accounting method. RESULTS: The average patient time in theatre for 57 PPVs was 72 min. The average in-surgery cost for staff was £297, consumables £619, and equipment £82 (total £997). The average out-of-surgery costs were £260, including nursing and medical staff, other consumables, eye drops and hospitalisation. The total cost was therefore £1634, including 30 % overheads. This cost estimate was an under-estimate because it did not include out-of-theatre consumables or equipment. The average reimbursed HRG tariff was £1701. CONCLUSIONS: The cost of undertaking PPV of intermediate complexity is likely to be higher than the reimbursed tariff, except for hospitals with high throughput, where amortisation costs benefit from economies of scale. Although this research was set in England, the methodology may provide a useful template for other countries.

Pars plana vitrectomy for vitreomacular traction syndrome: a systematic review and metaanalysis of safety and efficacy.

PURPOSE: To determine the safety and efficacy of pars plana vitrectomy for vitreomacular traction. METHODS: Articles reporting visual acuity change before and after pars plana vitrectomy were selected using a systematic literature review with predefined eligibility criteria. Visual acuities were converted to logarithm of the minimum angle of resolution (logMAR), weighted for study size, and pooled across studies. Safety outcomes were also pooled across studies. RESULTS: Twenty-one of 460 articles were eligible. Mean (±standard deviation) logMAR visual acuity improved from 0.67 ± 0.55 to 0.42 ± 0.45 (n = 259 eyes) after pars plana vitrectomy (from 20/94 to 20/53 Snellen). In series of at least 20 eyes, mean visual acuity improved in all 5 studies (sign test, P = 0.0625). Of 392 eyes, 9.2% lost visual acuity, 11.7% were unchanged, and 64.3% improved; 32.9% of 217 eyes gained ≥2 Snellen lines. The most common postoperative complications were cataract (34.7% of 304 eyes; 63.2% of 68 phakic eyes), epiretinal membrane (5.7% of 348 eyes), and retinal detachment (4.6% of 348 eyes). Cataract surgery was undertaken in 10.5% of eyes. CONCLUSION: The visual acuity gains after pars plana vitrectomy for vitreomacular traction are relatively modest, but visual acuity change may not fully reflect symptomatic relief.

Symptomatic vitreomacular adhesion.

BACKGROUND: Symptomatic vitreomacular adhesion describes symptomatic loss of visual function as a result of vitreous traction at the macula. METHODS: Literature review. RESULTS: Symptomatic vitreomacular adhesion can occur in isolation as vitreomacular traction, which may lead to the development of a macular hole, or it may occur alongside epiretinal membrane. It is likely to be associated with age-related macular degeneration and possibly diabetic maculopathy, although this is less certain. The treatment depends largely on the cause, but options include observation, vitrectomy, and pharmacologic vitreolysis. Small uncontrolled trials have also explored the use of an intravitreal gas bubble as a means of releasing VMA. If all cases of sVMA are considered together, then the burden of illness is substantial, with a prevalence of ∼0.35 per 100 population (excluding epiretinal membrane). Furthermore, there may be many more cases of undiagnosed sVMA. CONCLUSION: The recent introduction of ocriplasmin is likely to increase interest in sVMA. Clinical trials suggest that it has a role in the treatment of vitreomacular traction and Stages 1 to 3 macular holes but not primarily as a treatment of epiretinal membrane. Its role in other diseases associated with VMA remains to be determined.

Vitreous attachment in age-related macular degeneration, diabetic macular edema, and retinal vein occlusion: a systematic review and metaanalysis.

PURPOSE: To determine if there is an association of vitreous attachment and wet age-related macular degeneration (AMD), diabetic macular edema, and retinal vein occlusion. METHODS: Systematic review and metaanalysis. RESULTS: Sixteen of 1,025 articles were eligible. In wet AMD, the prevalence of vitreomacular adhesion and posterior vitreous detachment was 23% (654 eyes) and 41% (251), respectively. Vitreomacular adhesion prevalence was 2.15 times that of controls (95% confidence interval, 1.34-3.48; p = 0.002) and 2.54 times that of dry AMD (confidence interval, 0.88-7.36; p 0.09); posterior vitreous detachment prevalence was lower than controls (relative risk 0.77; confidence interval, 0.64-0.93; p = 0.007) and dry AMD (0.56; confidence interval, 0.27-1.14; p = 0.11). It was not possible to determine the prevalence of vitreous attachment in diabetic macular edema, but vitreomacular traction was present in 29% of 188 surgical cases. The prevalence of posterior vitreous detachment in eyes with central and branch retinal vein occlusion was 30% (56 eyes) and 31% (71 eyes), respectively, versus 25% (64 eyes) in controls. CONCLUSION: Observational studies of sufficient quality indicate that eyes with wet AMD have double the expected prevalence of vitreomacular adhesion and are less likely to have a posterior vitreous detachment. More controlled studies of diabetic macular edema and retinal vein occlusion are needed.