Determining the effect of low-dose isotretinoin on proliferative vitreoretinopathy: the DELIVER trial.

PURPOSE: To examine the effect of low-dose, oral isotretinoin in lowering the risk of proliferative vitreoretinopathy (PVR) following rhegmatogenous retinal detachment (RRD) repair. METHODS: Prospective, open label, dual-cohort study with pathology-matched historical controls. The prospective experimental arms included two cohorts, composed of 51 eyes with recurrent PVR-related RRD and 58 eyes with primary RRD associated with high-risk features for developing PVR. Eyes in the experimental arms received 20 mg of isotretinoin by mouth once daily for 12 weeks starting the day after surgical repair. The primary outcome measure was single surgery anatomical success rate at 3 months following the study surgery. RESULTS: The single surgery anatomic success rate was 78.4% versus 70.0% (p=0.358) in eyes with recurrent PVR-related retinal detachment exposed to isotretinoin versus historical controls, respectively. In eyes with RRD at high risk for developing PVR, the single surgery success rate was 84.5% versus 61.1% (p=0.005) for eyes exposed to isotretinoin versus historical controls, respectively. For eyes enrolled in the experimental arms, the most common isotretinoin-related side effects were dry skin/mucus membranes in 106 patients (97.2%), abnormal sleep/dreams in 4 patients (3.7%) and fatigue in 3 patients (2.8%). CONCLUSION: The management and prevention of PVR is challenging and complex. At the dose and duration given in this study, oral istotretinoin may reduce the risk of PVR-associated recurrent retinal detachment in eyes with primary RRD at high risk of developing PVR.

Choroidal vascular analysis in myopic eyes: evidence of foveal medium vessel layer thinning.

PURPOSE: To analyse morphologic features of the choroid in Non-pathological myopic eyes using spectral-domain (SD) optical coherence tomography (OCT). METHODS: Retrospective analysis of enhanced depth SD-OCT images of Non-pathological myopic eyes in comparison with age-matched healthy controls was performed. Choroidal thickness (CT) and large choroidal vessel thickness (LCVT) were measured at the fovea, 750 µm nasally from fovea (N750) and 750 µm temporally (T750) from fovea. Medium choroidal vessel thickness (MCVT) was calculated by subtracting LCVT from CT. Choriocapillaris was encompassed by MCVT, given its reduced thickness. Linear regression analysis evaluated the relationship between age and axial with CT, LCVT and MCVT. RESULTS: The study group comprised 42 eyes of 31 patients (mean age 46.13 ± 15.63; 15 females). Control group included 57 eyes of 34 patients (mean age of 42.3 ± 15.29; 24 females). Mean axial length in myopic eyes and control group was 26.57 ± 1.27 and 23.59 ± 0.99 mm respectively. Myopic eyes showed significant thinning of MCVT and CT at all locations (p < 0.0001) compared to controls, unlike LCVT (p > 0.05). With each decade, thinning of up to 37 µm in CT was noted along with thinning of LCVT (up to 22.6 µm) and MCVT (up to 25 µm). Each mm increase in axial length caused 38.2 µm thinning of choroid along with LCVT (<10 µm), however, MCVT showed more notable thinning (>30 µm). CONCLUSION: Significant thinning of MCVT was noted in non-pathological myopic eyes in comparison to healthy subjects. It appears that MCVT has stronger relationship with age and axial length.

Subfoveal Choroidal Vascularity in Myopia: Evidence From Spectral-Domain Optical Coherence Tomography.

BACKGROUND AND OBJECTIVE: To evaluate subfoveal choroidal vascularity in eyes with myopia in comparison to age-matched healthy subjects. PATIENTS AND METHODS: Retrospective analysis of single foveal enhanced depth imaging optical coherence tomography (EDI-OCT) scans of 30 eyes with myopia (axial length greater than 25 mm). Subfoveal choroidal vascularity was evaluated by calculating vessel-area-to-stromal-area ratio using a previously validated automated algorithm. RESULTS: The subfoveal stromal area was significantly smaller in myopes (0.95 mm3 ± 0.22 mm3) compared to controls (1.33 mm3 ± 0.23 mm3; P < .0001). However, there was no significant difference in vascular area or in vessel-area-to-stroma-area ratio between the groups (P = .15 and P = .16, respectively). Subfoveal choroidal vascularity percentage was also not significantly different between the two groups (P = .07). CONCLUSION: Subfoveal choroidal thinning in myopia is primarily associated with a reduction in choroidal stroma, not vascular components. This needs further exploration and has potential clinical applications. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:202-207.].

Pars plana vitrectomy and scleral buckle versus pars plana vitrectomy alone for patients with rhegmatogenous retinal detachment at high risk for proliferative vitreoretinopathy.

PURPOSE: To compare using pars plana vitrectomy (PPV) combined with a scleral buckle versus primary vitrectomy alone in patients with rhegmatogenous retinal detachment at high risk for postoperative proliferative vitreoretinopathy (PVR). METHODS: Six hundred and seventy-eight patients were identified from billing data as having rhegmatogenous retinal detachment between April 1, 2010 and August 1, 2012. Patients were considered at high risk for PVR if they presented with retinal detachment in 2 or more quadrants, retinal tears >1 clock hour, preoperative PVR, or vitreous hemorrhage. RESULTS: Of the 678 patients with rhegmatogenous retinal detachment, 65 were identified as high risk for PVR. Thirty-six patients were treated with simultaneous PPV-scleral buckle and 29 patients were treated with PPV alone, with an overall success rate of 63.1%. The use of PPV-scleral buckle was associated with significantly higher single surgery anatomical success compared with patients treated with PPV alone (odds ratio, 3.24; 95% confidence interval, 1.12-9.17; P = 0.029). Visual acuity at 3 months postprocedure or final follow-up was no different between the treatment groups. Overall, 23.1% of patients developed postoperative PVR with no difference between surgical approaches. CONCLUSION: For patients at high risk for PVR, PPV-scleral buckle was associated with significantly higher rates of anatomical success compared with PPV alone.

Outcomes of scleral buckle removal with and without concurrent prophylactic laser retinopexy.

OBJECTIVE: To present the outcomes of scleral buckle (SB) removal with and without concurrent prophylactic laser retinopexy. DESIGN: Retrospective, interventional case series. PARTICIPANTS: Eighty-seven eyes of 87 patients who had SB removal after primary rhegmatogenous retinal detachment repair. METHODS: All patients who had SB removal after primary rhegmatogenous retinal detachment repair from both Wills Eye Institute and University of Alberta from 2000 to 2011 were identified. All patients had a minimum of 6 months of follow-up. RESULTS: Eighty-seven patients met the study criteria. Primary indications for SB removal were extrusion (76%, n = 66), diplopia (8%, n = 7), infection (6%, n = 5), a combination of extrusion and infection (6%, n = 5), and others (5%, n = 4). Only 3 of 87 eyes (3.4%) developed a recurrent retinal detachment after SB removal. Only 1 eye (2.2%) from the group that received laser retinopexy (n = 45) at the time of SB removal had a retinal redetachment, whereas 2 eyes (4.2%) in the group that did not receive laser (n = 42) had a recurrent retinal detachment (p = 0.61). CONCLUSIONS: The overall rate of recurrent retinal detachment after SB removal was low. No significant difference in recurrent retinal detachment was found between the eyes that received prophylactic laser retinopexy compared with those that did not at the time of SB removal.

Neovascular events in eyes with central retinal vein occlusion undergoing serial bevacizumab or ranibizumab intravitreal injections: a retrospective review.

PURPOSE: To characterize the onset and type of neovascular events in eyes with central retinal vein occlusion (CRVO) undergoing serial anti-VEGF therapy. METHODS: Consecutive eyes undergoing serial intravitreal bevacizumab or ranibizumab injections for treatment of CME secondary to CRVO were identified. Pertinent data was retrospectively collected and included type and onset of the neovascular event, and the treatment free interval from last injection until the neovascular event. Kaplan-Meier life table analysis was performed to determine the differential effects of baseline perfusion status, early initiation of anti-VEGF treatment (within 3 months of CRVO onset) versus later treatment, and continuous (1-month±2 weeks) versus discontinuous treatment interval (>1.5 months) on time until neovascular event. RESULTS: Of 31 eligible eyes, 12 (39%) and 19 (61%) presented with perfused and ischemic CRVO, respectively. The mean duration from CRVO until the onset of any neovascular event was 17.0±10.3 months. The mean treatment-free interval prior to any neovascular event was 6.2±7.3 months. On average, 5.3±3.2 anti-VEGF injections were given prior to any neovascular event. Neovascularization of the iris or angle occurred in 18 eyes (58%), vitreous hemorrhage associated with neovascularization was observed in 9 eyes (29%) and neovascularization of the disc developed in 5 eyes (16%). Neovascular events showed a trend towards occurring later in eyes with perfused CRVO at baseline (log rank test, P=0.07). CONCLUSION: Neovascular events occur in eyes with CRVO undergoing serial anti-VEGF therapy, and these events may be delayed compared to the natural history of CRVO-associated neovascularization. Iris neovascularization occurred most frequently.

Postoperative vitreous hemorrhage after diabetic 23-gauge pars plana vitrectomy.

PURPOSE: To report the frequency of postoperative vitreous hemorrhage (VH) in eyes that underwent primary 23-gauge pars plana vitrectomy (PPV) for nonclearing VH resulting from proliferative diabetic retinopathy, as well as associated risk factors. DESIGN: Retrospective, consecutive, interventional case series. SETTING: Institutional (Retina Service of Wills Eye Institute). STUDY POPULATION: One hundred seventy-three eyes of 157 patients. INTERVENTION: Twenty-three-gauge PPV for nonclearing diabetic VH. MAIN OUTCOME MEASURES: Percentage of eyes in which postoperative VH developed, categorized as early, delayed, or severe persistent, as well as percentage requiring reoperation. RESULTS: During a mean follow-up of 32 weeks, 56 (32%) of 173 eyes demonstrated postoperative VH, categorized as early (8 eyes; 5%), delayed (13 eyes; 8%), or severe persistent (35 eyes; 20%). Twenty-two (13%) of 173 eyes required reoperation: 4 (50%) of 8 in the early group, 8 (62%) of 13 in the delayed group, and 10 (29%) of 35 in the severe persistent group. Mean preoperative logarithm of the minimum angle of resolution visual acuity was 1.5 (Snellen equivalent, approximately 20/600); mean postoperative VA was 0.65 (Snellen equivalent, approximately 20/90), a gain of 0.85 (P < .0001). Thirty-four (27%) of 127 eyes with complete scatter photocoagulation before undergoing PPV compared with 22 (48%) of 46 eyes with incomplete scatter photocoagulation before undergoing PPV demonstrated postoperative VH (P = .002). Other factors associated with postoperative VH included younger age (P = .022) and phakia (P = .036). CONCLUSIONS: Postoperative VH was not uncommon after initial 23-gauge PPV for diabetic VH and was associated with incomplete scatter photocoagulation, younger age, and phakia before PPV. However, only a minority of patients required reoperation.