Petros E. Carvounis

25-gauge vitrectomy using sulfur hexafluoride and no prone positioning for repair of macular holes.

Purpose: To report on the outcomes of 25-gauge pars plana vitrectomy using sulfur hexafluoride and no prone positioning for repair of macular holes. Methods: Retrospective case series of 44 consecutive patients who underwent pars plana vitrectomy with internal limiting membrane peeling for repair of stages 2 to 4 idiopathic macular holes using 20% to 30% sulfur hexafluoride. No postoperative prone positioning or gas augmentation was used. Results: The macular hole closure rate was 88.6%. There were no differences in the macular hole closure rates between phakic and pseudophakic patients (21 of 23 vs. 17 of 21, respectively) or among stages 2, 3, and 4 macular holes (12 of 13, 20 of 23, and 7 of 8, respectively). In eyes successfully operated on, visual acuity improved from 0.61 logarithm of the minimal angle of resolution (logMAR) (20 of 82) preoperatively to 0.483 logMAR (20 of 61) at 1 month and 0.396 logMAR (20 of 50) at a mean final follow-up of 10.8 months. Adverse effects were elevation of intraocular pressure to >30 mmHg in 7 (13.6%) of 44 patients on the first postoperative day, postoperative retinal detachments in 2 (4.5%) of 44 patients, and progression of cataract requiring cataract surgery in 7 (30.4%) of 23 phakic patients during follow-up. Conclusions: Macular hole closure rates similar to those achieved using pars plana vitrectomy with perfluoropropane and prone positioning can be achieved using sutureless 25-gauge vitrectomy with sulfur hexafluoride tamponade and no prone positioning for both phakic and pseudophakic patients.

Evaluation of Automated Teleretinal Screening Program for Diabetic Retinopathy

IMPORTANCE Diabetic retinopathy is a leading cause of blindness, but its detrimental effects are preventable with early detection and treatment. Screening for diabetic retinopathy has the potential to increase the number of cases treated early, especially in populations with limited access to care. OBJECTIVE To determine the efficacy of an automated algorithm in interpreting screening ophthalmoscopic photographs from patients with diabetes compared with a reading center interpretation. DESIGN, SETTING, AND PARTICIPANTS Retrospective cohort analysis of 15,015 patients with type 1 or 2 diabetes in the Harris Health System in Harris County, Texas, who had undergone a retinal screening examination and nonmydriatic fundus photography via the Intelligent Retinal Imaging System (IRIS) from June 2013 to April 2014 were included. The IRIS-based interpretations were compared with manual interpretation. The IRIS algorithm population statistics were calculated. MAIN OUTCOMES AND MEASURES Sensitivity and false-negative rate of the IRIS computer-based algorithm compared with reading center interpretation of the same images. RESULTS A total of 15 015 consecutive patients (aged 18-98 years); mean 54.3 years with known type 1 or 2 diabetes underwent nonmydriatic fundus photography for a diabetic retinopathy screening examination. The sensitivity of the IRIS algorithm in detecting sight-threatening diabetic eye disease compared with the reading center interpretation was 66.4% (95% CI, 62.8%-69.9%) with a false-negative rate of 2%. The specificity was 72.8% (95% CI, 72.0%-73.5%). In a population where 15.8% of people with diabetes have sight-threatening diabetic eye disease, the IRIS algorithm positive predictive value was 10.8% (95% CI, 9.6%-11.9%) and the negative predictive value was 97.8% (95% CI, 96.8%-98.6%). CONCLUSIONS AND RELEVANCE In this large urban setting, the IRIS computer algorithm-based screening program had a high sensitivity and a low false-negative rate, suggesting that it may be an effective alternative to conventional reading center image interpretation. The IRIS algorithm shows promise as a screening program, but algorithm refinement is needed to achieve better performance. Further studies of patient safety, cost-effectiveness, and widespread applications of this type of algorithm should be pursued to better understand the role of teleretinal imaging and automated analysis in the global health care system.

Current Treatment of Toxoplasma Retinochoroiditis: An Evidence-Based Review

Objective. To perform an evidence-based review of treatments for Toxoplasma retinochoroiditis (TRC). Methods. A systematic literature search was performed using the PubMed database and the key phrase “ocular toxoplasmosis treatment” and the filter for “controlled clinical trial” and “randomized clinical trial” as well as OVID medline (1946 to May week 2 2014) using the keyword ‘‘ocular toxoplasmosis”. The included studies were used to evaluate the various treatment modalities of TRC. Results. The electronic search yielded a total of 974 publications of which 44 reported on the treatment of ocular toxoplasmosis. There were 9 randomized controlled studies and an additional 3 comparative studies on the treatment of acute TRC with systemic or intravitreous antibiotics or on reducing the recurrences of TRC. Endpoints of studies included visual acuity improvement, inflammatory response, lesion size changes, recurrences of lesions, and adverse effects of medications. Conclusions. There was conflicting evidence as to the effectiveness of systemic antibiotics for TRC. There is no evidence to support that one antibiotic regimen is superior to another so choice needs to be informed by the safety profile. Intravitreous clindamycin with dexamethasone seems to be as effective as systemic treatments. There is currently level I evidence that intermittent trimethoprim-sulfamethoxazole prevents recurrence of the disease.

Iris-sutured intraocular lenses for ectopia lentis in children

PURPOSE: To compare outcomes and complications of pars plana lensectomy–vitrectomy (PPL–PPV) for the management of ectopia lentis in children with and without a foldable iris‐sutured intraocular lens (IOL). SETTING: Department of Ophthalmology, Baylor College of Medicine, Houston, Texas, USA. METHODS: This study comprised 22 eyes of 12 consecutive pediatric patients with ectopia lentis who had PPL–PPV by the same vitreoretinal surgeon with (12 eyes; Group L) or without (10 eyes; Group A) insertion of a foldable iris‐sutured IOL between June 1998 and October 2006. Outcome measures included the proportion of eyes achieving visual acuity of 20/40 or better, mean logMAR visual acuity, and complications. RESULTS: There was no statistically significant difference between the 2 groups in the proportion of eyes achieving a visual acuity of 20/40 or better (Group A: 5/10; Group L: 10/12) (P = .17) or the mean postoperative best corrected logMAR visual acuity (Group A: 0.41 [20/52]; Group L: 0.24 [20/35]) (P = .18). Complications included IOL dislocation in 4 (33%) of 12 eyes in Group L (95% confidence interval, 11%‐65%). Eyes with dislocated IOLs had retrieval with resuturing of the IOL to the iris and had a mean visual acuity of 20/27 at the last follow‐up. No retinal detachment was observed. CONCLUSION: Pars plana lensectomy–vitrectomy with iris‐fixation of a foldable IOL for the management of ectopia lentis yielded visual outcomes as least as good as those of optically corrected aphakia with a significant risk for dislocation.

Long-term visual outcomes following lens-sparing vitrectomy for retinopathy of prematurity

Aim To describe the long-term outcomes of lens-sparing vitrectomy (LSV) for retinopathy of prematurity (ROP). Methods Single-centre retrospective case series of eyes that underwent LSV for ROP between 1998 and 2005 and had a follow-up of at least 5 years. The primary outcome was the mean visual acuity, and secondary outcomes were the proportion of eyes without functional vision, proportion of eyes with anatomic success, proportion of Stage 4A eyes with vision better than 20/400, proportion of Stage 4B eyes with vision better than 20/800. Results Thirty-seven eyes of 30 patients (mean age at last follow-up: 7.1 years) were included in the study, while an additional 23 patients had been lost to follow-up and were not included in the study. Of eyes that underwent LSV for Stage 4A or 4B: 63% had measurable visual acuity (mean logMAR 0.92 for Stage 4A, 1.63 for Stage 4B), 19% had form vision, but neurological comorbidities precluded visual acuity measurement, and the remaining 18% had light perception or no light perception. Conclusions While most eyes that underwent LSV for Stage 4A or 4B ROP maintain useful vision with long-term follow-up, approximately one-fifth of eyes had no functional vision, and in a further fifth, vision could not be measured due to severe neurological impairment.

Toxicity of high-dose intravitreal adalimumab (Humira) in the rabbit.

PURPOSE To evaluate the ocular toxicity of escalating doses of intravitreous adalimumab (Humira®) in the rabbit eye. METHODS Thirty New Zealand albino rabbits received intravitreous injections of 0.5 mg (6 eyes), 1.0 mg (6 eyes), 2.5 mg (6 eyes), 5 mg (6 eyes), and 10 mg (6 eyes) adalimumab. Slit lamp biomicroscopy and fundoscopy were carried out at baseline, day 7, and day 14 after intravitreous injection, whereas electroretinography (ERG) was carried out at baseline and day 14. Animals were euthanized on day 14, and histopathological examination of the eyes was performed. RESULTS Slit lamp biomicroscopy and fundoscopy were normal in all eyes receiving doses up to 5 mg. In the 10 mg group, 3 of 6 eyes showed mild anterior chamber inflammatory reaction on day 7. Similarly, scotopic and photopic a- and b-wave ERG amplitudes at baseline and day 14 were similar in all groups up to 5 mg, but there was a significant decrease in the photopic-wave ERG response in the 10 mg group (P=0.046). Finally, histopathology demonstrated no differences among eyes receiving balanced salt solution, 0.5, 1.0, 2.5, 5.0, or 10 mg of adalimumab. CONCLUSIONS Intravitreous adalimumab exhibited no associated ocular short-term toxicity in rabbit eyes up to the 5 mg dose. In the 10 mg group mild clinical findings and ERG amplitude reduction could reflect early toxicity.

Bacillus Cereus Endophthalmitis Following Intravitreous Bevacizumab Injection

The first case of Bacillus cereus endophthalmitis following an intravitreous injection of bevacizumab is described. A 77-year-old man presented to a retina specialist with an active choroidal neovascularization related to age-related macular degeneration for which he received intravitreous bevacizumab (1.25 mg) and post-injection topical gatifloxacin. Eight hours later, the patient woke up with excruciating pain and a decline in vision associated with nausea and vomiting. A vitreous biopsy was performed that revealed B. cereus. Despite intravitreous injections of vancomycin and ceftazidime on day 1 and pars plana vitrectomy with repeat intravitreous injections on day 3, the eye did not recover light perception.

Retinal Pigment Epithelial Tears and the Management of Exudative Age-Related Macular Degeneration

Tears of the retinal pigment epithelium (RPE) are a known and potentially catastrophic complication of exudative age-related macular degeneration (AMD). Eyes with vascularized retinal pigment epithelial detachments (PED) are especially at risk for the development of RPE tears. This long-recognized complication faces increased scrutiny in an era of improved anti-angiogenic treatments for AMD, particularly given that these newly developed therapeutics have been implicated as a potential factor in the formation of some RPE tears.

Outcomes of vitrectomy for tractional retinal detachment in diabetic retinopathy.

Diabetes remains the leading cause of visual impairment among working-age adults in the United States. As the prevalence of diabetes grows, so too does the burden of visual loss on patients. The natural history of proliferative diabetic retinopathy (PDR) is poor, with approximately 44% of patients experiencing severe visual loss (<5/200) within 5 years of developing high-risk PDR. The majority of visual loss among these patients results from progression of the ischemic sequelae of highrisk PDR such as neovascular glaucoma (NVG), nonclearing vitreous hemorrhage, and tractional retinal detachment (TRD). Nonclearing vitreous hemorrhage and TRD involving the macula remain the primary surgical indications for vitrectomy in diabetic retinopathy. This review will focus on the use of pars plana vitrectomy (PPV) in the repair of TRD related to PDR and specifically on the preoperative systemic and ocular factors influencing ease of surgery and visual outcomes, intraoperative techniques and complications, microincisional vitrectomy, postoperative complications, and finally visual outcomes of vitrectomy for TRD related to PDR.

Current management of vitreous hemorrhage due to proliferative diabetic retinopathy

In 1970, Robert Machemer performed the first pars plana vitrectomy (PPV) on a patient with a nonclearing diabetic vitreous hemorrhage (NCVH) of 5 years’ duration, achieving an improvement in visual acuity from 2/200 to 20/50.1–3 Indeed, NCVH was one of the main indications for retinal surgery in the early days of vitrectomy. 4 The role of PPV for vitreous hemorrhage was further refined in 1985 when the first results of the Diabetic Retinopathy Vitrectomy Study (DRVS) were reported.5–6 Since that time there have been a multitude of refinements in surgical instrumentation and techniques improving surgical outcomes, and the role of anti-VEGF medications as potential adjuvant or treatment has been evaluated. This review focuses on the current medical and surgical management of NCVH. Pathophysiology Retinal ischemia results in hypoxia which results in the production of hypoxia induced factor (HIF). HIF enhances the expression of angiogenic factors including insulin-like growth factor 1, basic fibroblast growth factor, erythropoietin, and vascular endothelial growth factor (VEGF) amongst others.7–12 Such angiogenic factors are present in the vitreous,7,10–11, 13–15 fibrovascular membranes 8, 16–17 and whole retinas 18 of patients with proliferative diabetic retinopathy and lead to the development of neovascular buds from retinal blood vessels. 19 This neovascular tissue proliferates and invades the potential space between the retina and the posterior hyaloid face and later the posterior lamellae of the cortical vitreous, producing a firm adhesion.20–21 The vessels continue to proliferate and subsequently develop an increasingly fibrous component. Localized traction from the posterior hyaloid face or contraction of the fibrous element of this fibrovascular complex leads to traction on the friable neovascular tissue and retina, leading to a vitreous hemorrhage. This may stimulate further fibrosis and vitreous contraction, and ultimately lead to a traction retinal detachment. 22