Tatjana Josifova

Anatomical and functional outcome in brilliant blue G assisted chromovitrectomy

Purpose:  To evaluate the potential of brilliant blue G (BBG) for intraoperative staining of the inner limiting membrane (ILM) with respect to staining properties and surgical outcome.

Quantification of Contrast Recognizability during Brilliant Blue G- and Indocyanine Green-Assisted Chromovitrectomy.

PURPOSE To evaluate the potential of brilliant blue G (BBG) and indocyanine green (ICG) for intraoperative staining of the internal limiting membrane (ILM) with respect to perceivable contrast. METHODS In a retrospective clinical case series the authors analyzed 26 consecutive chromovitrectomy interventions in 26 patients with macular holes, epiretinal fibrosis, vitreoretinal traction syndromes, or persistent macular edema. Fourteen subjects underwent ICG and 12 subjects, BBG chromovitrectomy. The main outcome measure was the difference in chromaticity between the stained ILM and the unstained underlying retina, measured by means of a novel objective and quantitative video-based analysis method to describe color contrast strengths as they are perceived by the human eye. RESULTS Objective chromaticity measurements of the intraoperative videos of all 26 interventions showed a significantly inferior contrast for BBG compared with that of ICG (BBG = 6.1, ICG = 14.9; P = 3.885 × 10⁻¹⁵). CONCLUSIONS As an adjunct to chromovitrectomy to stain the ILM, BBG yields a significantly less well discernible contrast to the human eye than that of ICG under the premises of this study.

Quantification of Contrast Recognizability in Sequential Epiretinal Membrane Removal and Internal Limiting Membrane Peeling in Trypan Blue-Assisted Macular Surgery

Purpose: To evaluate the selectivity and strength of intraoperative trypan blue staining during removal of epiretinal membranes (ERMs) and the internal limiting membrane. Methods: Based on intraoperative videos, 51 consecutive chromovitrectomies in 51 patients with macular holes, macular pucker, vitreomacular traction syndromes, or persistent macular edema were retrospectively studied. Fifteen subjects underwent trypan blue, 14 indocyanine green, and 22 brilliant blue G chromovitrectomy. The main outcome measure was the color contrast between stained internal limiting membrane or ERM and the underlying unstained tissue by means of objective, quantitative, semiautomated chromaticity difference measurements. Results: Trypan blue stains both ERM and the internal limiting membrane (average chromaticity scores 8.51 and 7.09, respectively; P = 0.48). Internal limiting membrane chromaticity scores were similar for trypan blue (7.09) and brilliant blue G (6.81; P = 0.71) but clearly higher for indocyanine green (15.81; P = 2.45 × 10−5). Conclusion: Under the premises of our study, trypan blue stains both ERM and the internal limiting membrane. Trypan blues staining capacity of the internal limiting membrane is similar to that of brilliant blue G but significantly inferior compared with indocyanine green. Trypan blue, thus, represents a useful vital dye for chromovitrectomy, particularly in the presence of ERM, where it allows a sequential approach.

Clinical Risk Factors for Poor Anatomic Response to Ranibizumab in Neovascular Age-Related Macular Degeneration §

Purpose: To identify OCT-based anatomical features and clinical characteristics for poor central retinal thickness (CRT) response to ranibizumab in neovascular age-related macular degeneration (AMD). Patients and Methods: Investigating our electronic patient records (Eyeswide), patients with neovascular AMD treated with intravitreal injections of 0.5mg/0.05ml ranibizumab were identified and their notes reviewed. Data collected included gender, age, initial best-corrected visual acuity (BCVA), prior photodynamic therapy, lesion type (classic versus occult), type of macular edema (intraretinal fluid, subretinal fluid, pigment epithelium detachment) and the total number of previous ranibizumab injections. Results: A total of 210 eyes of 182 patients with neovascular AMD were identified. Mean follow-up time was 1.34 years (SD ± 0.77). Central retinal thickness reduction in women was significantly inferior to that in men (p=0.05). Patients with cystoid type macular edema had significantly greater reduction in CRT compared to patients with subretinal fluid (p<0.001) or pigment epithelium detachment (p<0.001). The percentage drop of CRT was no longer statistically significant after the sixth injection. Age, initial BCVA, prior photodynamic therapy and lesion type had no statistically effect on CRT response. Conclusion: Risk factors for poor central retinal thickness response to ranibizumab include female gender and patients with predominant subretinal fluid or pigment epithelium detachment. Furthermore, the anatomical response decreased after the sixth injection of ranibizumab.

Proliferative diabetic retinopathy: predictive and preventive measures at hypoxia induced retinal changes

Retinal vasculature changes in diabetic patients are most common cause of blindness among eye diseases. Numerous studies have explored the role of the agiogenic factors in the progression of diabetic retinopathy (DR). The balance between angiogenic and antiangiogenic factors has a determining role in the DR progression. Current treatment modalities include laser photocoagulation, intravitreal drug application, and pars plana vitrectomy (ppv). These maneuvers are employed with occurrence of advanced retinal changes. New diagnostic approaches can provide better information for the initial retinal changes thereby requiring a new DR classification and treatment guidelines. The results that are expected from Diabetic Retinopathy Clinical Research Network (DRCR) are at the level where prediction and prevention can not be made. Innovative molecular-imaging technology, can pave the way for application of novel clinical approaches. Identification of pathology-specific biomarkers and their application to diagnosis and treatment, support the individualized treatment algorithms.

What did inspire me to write the abstract for the EPMA Congress

Case Report Type 1 Diabetes Mellitus (DM) Male 22 years of age (Figure 1) Insulin dependent since 2003 Visual acuity: OD: 0,10 OS: Light Perception Preparing for surgical treatment Operation rejected because of: Blood hypertension (230/110 mmHg) HBA1C: 10.7 % Anemia Renal Insufficiency (not diagnosed) Hart ischemic changes, left ventricular hypertrophy (not diagnosed) DM is a major cause of avoidable blindness all over the world. Patients with diabetic retinopathy (DR) are 25 times more likely to become blind than non-diabetics. Prevalence of type 1 diabetes is 10-15% of the diabetic population. Prevalence of DR in Wisconsin Epidemiological Study of Diabetic Retinopathy was 50.1 and 54.2% in the diabetes control and complications trial in type 1 diabetes [1] and 35-39% in United Kingdom Prospective Diabetes Study in type 2 diabetes [2]. In two studies from India, the prevalence of DR in type 2 diabetes patients were 34.1% and 37% [3].WHO estimates India has 31.7 million diabetic subjects at present. In USA, DR is the leading cause of new blindness in people 25-74 years of age. Approximately 700,000 persons have proliferative DR (PDR). Each year another 65,000 are diagnosed with the condition. A recent study has estimated that among people with diabetes aged 40 or older, 28.5% will develop DR. Worldwide 20 million people have PDR (very severe eye complication), with this number projected to increase to over 30 million by 2030. After 10 years of onset of DM, blindness was 1.8, 4.0 and 4.8% in type 1, insulin-treated type 2 and noninsulin-treated type 2 patients, respectively. In these three groups of patients, the 10-year incidence visual impairment (loss of 15 letters on a scale of 0-70 letters) was 9.4, 37.2 and 23.9%, respectively [4]. Good glycemic control arrests the development and progression of DR, but still there are a lot of factors that can influence the DR visual loss. Technological advances have improved the diagnostic accuracy of screening methods and given an access to the diabetic patients to the specialist care. In the last decades, the treatment strategies have been revised and besides laser photocoagulation, include surgical interventions and pharmacotherapies. DR will often go unnoticed when the condition is in its early stages but advanced symptoms can include blurred or sudden vision loss. Diabetics are advised to take advantage of the eye screenings which are offered free of charge in the UK, to detect any signs of the disease.

Diabetic Retinopathy: The Need for Predictive, Preventive and Personalized Approach to Management

For over six decades, there has been continuous improvement in our understanding of fundamental processes underlying the ocular complications of diabetes. Recent studies provide us with a very precious and detailed understanding of molecular mechanisms involved in the evolution of diabetic retinopathy (DR). The novel therapeutic approaches include intravitreal steroid and Anti-Vascular Endothelial Growth Factor (VEGF) therapy modalities. The latest clinical investigations include randomized multicenter clinical trials. The results seem to be encouraging with respect to short-term control of diabetic macular edema, but recurrence can occur after initiation of treatment. Laser photocoagulation and surgical methods, such as pars plana vitrectomy, have undergone some changes in the last years, but in general, the principle of their action remain the same. Combination of ocular pharmacotherapy and laser photocoagulation is a subject of ongoing investigations.