Referrals for proliferative diabetic retinopathy from two UK diabetic retinopathy screening services: a 10-year analysis of visual outcomes, requirement for vitrectomy, and mortality.

BACKGROUND/OBJECTIVES: To determine long-term outcomes of patients referred with proliferative diabetic retinopathy (PDR) from diabetic eye screening programmes (DESP) to tertiary care centres in the United Kingdom (UK). METHODS: Retrospective multicentre study of patients referred from two DESPs in the UK over a 36-month period (2007-9) and followed-up for 10 years. Critical outcomes included severe vision loss (SVL) and the need for vitrectomy. Other outcomes assessed included moderate vision loss (MVL), and patient survival time. Univariate and multiple variable Cox proportional hazards regressions were used to analyse survival outcomes. RESULTS: 212 eyes of 150 patients were referred with a diagnosis of PDR. 109 eyes of 72 patients were confirmed to have active PDR and included in the study. 61% of patients had low-risk PDR, while 39% exhibited high-risk features in at least one eye. Eight (7.3%) eyes developed SVL and 16 (14.7%) MVL during follow up. Vitrectomy was required in 24% (95% CI: 15 to 31%) of all PDR eyes and was most commonly performed for vitreous haemorrhage (65%). The 10-year survival in all PDR patients was 76% (95% CI: 63 to 85%) with the mean time to death for all deceased patients being 5.4 ± 3.6 years. On multivariable analysis, only age was found to have a significant association with the survival of patients with PDR. CONCLUSIONS: During the 10 year follow up SVL was uncommon, but MVL occurred in almost one-fifth of the eyes. Approximately 1 in 4 eyes required vitrectomy, highlighting its significance in patient management.

ILUVIEN® technology in the treatment of center-involving diabetic macular edema: a review of the literature.

Diabetic macular edema (DME) is one of the major causes of blindness, caused primarily by hyperglycemia and results from multiple pathological processes mostly secondary to increased levels of VEGF and other inflammatory cytokines. DME management includes control of systemic risk factors together with laser photocoagulation, frequent intraocular injections of anti-VEGF agents and steroids implants. Recent adoption of novel alternative drug delivery options has led to the development of sustained release ocular implants with longer duration of action with less injection frequency. This article will review the pharmacology and clinical data in terms of efficacy, safety and benefits of the sustained release steroid implants in treatment of DME with special emphasis on the fluocinolone acetonide ILUVIEN® implant.

Multi-Scale Segmentation and Surface Fitting for Measuring 3-D Macular Holes.

Macular holes are blinding conditions, where a hole develops in the central part of retina, resulting in reduced central vision. The prognosis and treatment options are related to a number of variables, including the macular hole size and shape. High-resolution spectral domain optical coherence tomography allows precise imaging of the macular hole geometry in three dimensions, but the measurement of these by human observers is time-consuming and prone to high inter- and intra-observer variability, being characteristically measured in 2-D rather than 3-D. We introduce several novel techniques to automatically retrieve accurate 3-D measurements of the macular hole, including: surface area, base area, base diameter, top area, top diameter, height, and minimum diameter. Specifically, we introduce a multi-scale 3-D level set segmentation approach based on a state-of-the-art level set method, and we introduce novel curvature-based cutting and 3-D measurement procedures. The algorithm is fully automatic, and we validate our extracted measurements both qualitatively and quantitatively, where our results show the method to be robust across a variety of scenarios. Our automated processes are considered a significant contribution for clinical applications.

Vitreoretinal interface abnormalities in patients treatedwith ranibizumab for diabetic macular oedema.

PURPOSE: Intravitreal anti-vascular endothelial growth factor (VEGF) agents are effective in the treatment of central involving diabetic macular oedema (DMO). Vitreoretinal interface abnormalities (VRIA) are common in patients with DMO, and the effect of these on the response to anti-VEGF treatment is unclear. Furthermore the effect of anti-VEGF agents on the VRIA itself is uncertain. METHOD: Prospective study of consecutive patients treated with ranibizumab (RZB) for DMO as part of routine clinical care in one eye unit over a 1-year period. Visual acuity (Va), central retinal thickness (CRT) and injection frequency data was recorded on an electronic database. Treatment was initiated with four monthly RZB injections and then a monthly PRN regime. All patients underwent high-density spectral-domain optical coherence tomography (SDOCT) at baseline and 12 months. The SDOCTs were graded by two observers masked to the outcome. RESULTS: One hundred and four eyes (77 patients) were included in the analysis. The mean age was 62 years, and 62% were male. The mean presenting vision was 62 letters and CRT 472 µm. Eighty eyes retained stable Va, and 17 had an improvement in Va. At baseline, 39 eyes had associated focal vitreomacular adhesion (VMA) and by 12 months this reduced to 30 (p = 0.04), with 12 releasing VMA and three developing it. Patients with VMA had significantly better final Va than those without VMA. Improvement in CRT was greatest in those where VMA released during the study. Forty-five eyes had some degree of foveal involving epiretinal membrane (ERM) at baseline, and 28 were considered to have clinically significant ERM. There was no clinically relevant change in ERM during the study. Patients with significant ERM at baseline had a lower final vision. Multivariate analysis showed that ERM and more severe retinopathy at baseline were predictive of less visual improvement (p < 0.01). Shorter intraretinal cyst length, ERM and the absence of VMA at baseline were predictive of a worsened anatomical response (p < 0.001). CONCLUSION: VRIA are related to outcome in patients treated with RZB. ERM was associated with a worsened visual and anatomic response, and VMA with an improved anatomical response particularly when spontaneous VMA release occurred during treatment. The presence and severity of ERM was not affected by RZB treatment.

The association between retinal vascular geometry changes and diabetic retinopathy and their role in prediction of progression--an exploratory study.

BACKGROUND: The study describes the relationship of retinal vascular geometry (RVG) to severity of diabetic retinopathy (DR), and its predictive role for subsequent development of proliferative diabetic retinopathy (PDR). METHODS: The research project comprises of two stages. Firstly, a comparative study of diabetic patients with different grades of DR. (No DR: Minimal non-proliferative DR: Severe non-proliferative DR: PDR) (10:10: 12: 19). Analysed RVG features including vascular widths and branching angles were compared between patient cohorts. A preliminary statistical model for determination of the retinopathy grade of patients, using these features, is presented. Secondly, in a longitudinal predictive study, RVG features were analysed for diabetic patients with progressive DR over 7 years. RVG at baseline was examined to determine risk for subsequent PDR development. RESULTS: In the comparative study, increased DR severity was associated with gradual vascular dilatation (p = 0.000), and widening of the bifurcating angle (p = 0.000) with increase in smaller-child-vessel branching angle (p = 0.027). Type 2 diabetes and increased diabetes duration were associated with increased vascular width (p = <0.05 In the predictive study, at baseline, reduced small-child vascular width (OR = 0.73 (95% CI 0.58-0.92)), was predictive of future progression to PDR. CONCLUSIONS: The study findings suggest that RVG alterations can act as novel markers indicative of progression of DR severity and establishment of PDR. RVG may also have a potential predictive role in determining the risk of future retinopathy progression.

Combined phacoemulsification and transpupillary removal of heavy silicone oil.

We describe a technique for heavy silicone oil removal combined with phacoemulsification and intraocular lens insertion without scleral incisions or sutures using a modified 16-gauge cannula. The technique is less invasive than other techniques for removing silicone oil and does not interfere with the uveal tract or the peripheral retina.

Vitrectomy with membrane peeling for vasocentric idiopathic epiretinal membranes.

PURPOSE: To report the clinical course and outcome of surgery for idiopathic epiretinal membranes (ERMs) centered on retinal blood vessels. METHODS: Retrospective observational case series review of the case records of 15 patients with idiopathic ERMs overlying retinal blood vessels, of whom 9 underwent vitrectomy with membrane peeling. The patients attended two eye departments under the care of four vitreoretinal surgeons with a total of more than 50 years of surgical experience. RESULTS: The patients were aged 12-74 years (mean = 34.3 years). Difficulties were experienced in achieving vitreoretinal and membranoretinal separation in the 9 eyes undergoing vitreous microsurgery. Recurrent ERM formation occurred in 8 of these eyes (89%) of which 6 underwent revision vitrectomy. Visual improvement was achieved in 55% of patients. Mean follow-up was 2.5 years. CONCLUSIONS: The authors describe a subgroup of patients with idiopathic ERMs in which the membrane is centered over a large retinal vessel. This occurs predominantly but not exclusively in a young age group. Surgical removal is characterized by a high recurrence rate.

Assessment of stereoscopic optic disc images using an autostereoscopic screen - experimental study.

BACKGROUND: Stereoscopic assessment of the optic disc morphology is an important part of the care of patients with glaucoma. The aim of this study was to assess stereoviewing of stereoscopic optic disc images using an example of the new technology of autostereoscopic screens compared to the liquid shutter goggles. METHODS: Independent assessment of glaucomatous disc characteristics and measurement of optic disc and cup parameters whilst using either an autostereoscopic screen or liquid crystal shutter goggles synchronized with a view switching display. The main outcome measures were inter-modality agreements between the two used modalities as evaluated by the weighted kappa test and Bland Altman plots. RESULTS: Inter-modality agreement for measuring optic disc parameters was good [Average kappa coefficient for vertical Cup/Disc ratio was 0.78 (95% CI 0.62-0.91) and 0.81 (95% CI 0.6-0.92) for observer 1 and 2 respectively]. Agreement between modalities for assessing optic disc characteristics for glaucoma on a five-point scale was very good with a kappa value of 0.97. CONCLUSION: This study compared two different methods of stereo viewing. The results of assessment of the different optic disc and cup parameters were comparable using an example of the newly developing autostereoscopic display technologies as compared to the shutter goggles system used. The Inter-modality agreement was high. This new technology carries potential clinical usability benefits in different areas of ophthalmic practice.

Refractile superficial retinal crystals and chronic retinal detachment: case report.

BACKGROUND: Few previous reports have described the presence of retinal refractile opacities at the macular area in patients presenting with longstanding peripheral retinal detachment. The exact nature of these opacities is unknown. CASE PRESENTATION: Two patients were referred with an abnormal appearance of refractile opacities in the macular area noted during routine examination. Both were found to have longstanding peripheral retinal detachments. Subretinal fluid analysis of one patient revealed the presence of multiple birefringent crystals. We hypothesise that these crystals are the origin of the refractile macular opacities noted. CONCLUSION: This report describes the rare presentation of asymptomatic peripheral retinal detachment by the detection of refractile macular opacities on routine examination. It highlights the importance of meticulous peripheral retinal examination in these cases. The article also describes the findings of the subretinal fluid analysis and discusses the possible hypothesis behind their appearance.

The combination of intravitreal triamcinolone and phacoemulsification surgery in patients with diabeticfoveal oedema and cataract.

BACKGROUND: The management of diabetic patients with refractory macular oedema or patients with no adequate pre-operative view to administer laser treatment provide a challenge to the ophthalmologist. We wished to assess the use, safety and effect of intravitreal triamcinolone injection at the time of cataract surgery in patients with diabetic foveal oedema and sight limiting lens opacities. METHOD: This was a longitudinal non-randomised prospective pilot study in 18 eyes (12 patients). All patients had visually significant lens opacities and either persistent diabetic foveal oedema unresponsive to laser treatment-group A, or foveal oedema with no adequate pre-operative view for laser treatment- group B. The cataract surgery was carried out under full aseptic technique using a self-sealing temporal incision and a foldable acrylic lens. Intravitreal triamcinolone was given infratemporally pars plana at the completion of the cataract surgery. The patients were reviewed at day 5, 2 weeks, 2 months and then every 3 months as required. The Wilcoxin matched-pairs test was used to assess the significance of the improvement in visual acuity at 2 months. RESULTS: Twelve patients with a total of 18 eyes were included in the study. There were 10 patients (15 eyes) in group A and 3 patients (3 eyes) in group B. Preoperatively 16 of the 18 eyes had a visual acuity of 6/24 or worse. Postoperatively 83% of patients had completely dry foveae at 2 weeks. Best-corrected visual acuities at two months review ranged from 6/6 to CF with 9 eyes (50%) achieving 6/12 or better (7 eyes (47%) in group A and 2 eyes (67%) in group B). Three eyes had no recorded improvement in visual acuity, but no eyes had deterioration in acuity. The improvement in visual acuity was significant at p = 0.001. There were no significant sight threatening complications. CONCLUSION: Intravitreal triamcinolone has been shown to lead to an improvement in macular oedema and visual improvement in diabetic patients not undergoing cataract surgery but has not, to our knowledge, been previously used in a study like this one.We suggest that intravitreal injection at the time of cataract surgery could be carried out safely with encouraging visual outcomes in patients with diabetic foveal oedema and cataract.