Controlling a Digital Cursor With a Sterile Gyroscopic Mouse in Digitally Assisted Vitreoretinal Surgery.

PURPOSE: To describe our experience using the gyroscopic mouse in digitally assisted vitreoretinal surgery. METHODS: We used a commercially available gyroscopic mouse to control the on-screen cursor of the NGENUITY System for digitally assisted vitreoretinal surgery. The gyroscopic mouse is sealed in a clear sterile plastic bag to allow for intraoperative use. This allowed both the surgeon and assistant to be fully scrubbed while retaining full control of the NGENUITY system's functions. The mouse also allowed the mentor to provide detailed instructions through the on-screen cursor by highlighting important landmarks. CONCLUSION: Using a sterile gyroscopic mouse improved the teaching utility and surgical workflow of digitally assisted vitreoretinal surgery.

Anti-Vegf therapy leads to an improvement in grade of retinal pigment epithelium alterations on single layer retinal pigment epithelium map in diabetic macular edema.

PURPOSE: In bovine retinal pigment epithelium (RPE) cells, increased secretion of vascular endothelial growth factor (VEGF) has a positive linear association with proliferation of RPE. Spectral domain optical coherence tomography (SD-OCT) based improvement in grades of topographic retinal pigment epithelium alterations (RPE-A), were evaluated after intravitreal anti-VEGF therapy, in diabetic macular edema (DME), for the first time. METHODS: A tertiary care center-based, prospective study. Forty-four consecutive patients, 40-65 years of age with type 2 diabetes mellitus (DM) with DME, were administered three doses of anti-VEGF therapy at monthly intervals. Pre- and post-intervention SD-OCT was done and central sub field thickness (CST), cube average thickness (CAT) and topographic grades of RPE-A were assessed using single layer RPE map (SL-RPE) as; Grade 0: No alterations, Grade 1: Alteration in two quadrants, Grade 2: Alteration in more than two quadrants. RESULTS: CST decreased from 354.2 ± 16.0 µm pre-intervention to 233.2 ± 7.9 µm post-intervention. CAT reduced from 340.6 ± 6.5 µm pre-intervention to 274.1 ± 5.1 µm post-intervention. Significant improvement in grades of RPE-A pre- v/s post-intervention were observed. (Grade 0: 0 v/s 39; Grade 1: 17 v/s 3; Grade 2: 27 v/s 2) (p < 0.001). CONCLUSION: Anti-VEGF therapy is associated with an improvement in grades of RPE-A in DME.The study was registered with the Clinical Trial Registry of India (CTRI/2019/03/018135).

Increased serum cortisol is associated with alterations in cross-sectional and topographic OCT parameters in diabetic retinopathy: a preliminary study.

PURPOSE: Cortisol, a steroid hormone, plays an essential role in metabolic processes of diabetes mellitus. This study for the first time evaluated the association of serum cortisol with spectral domain optical coherence tomography (SD-OCT)-based cross-sectional and topographic parameters with severity of diabetic retinopathy (DR). METHODS: A tertiary care center-based preliminary study was undertaken. Fourteen consecutive cases of DR and fifteen healthy controls were included. Cases were graded according to ETDRS classification: non-proliferative DR (NPDR, n = 8) and proliferative DR (PDR, n = 6). All study subjects underwent complete ophthalmological evaluation. Serum cortisol was analyzed using chemiluminescence microparticle assay method. Central subfield thickness (CST), cube average thickness (CAT), cube volume (CV), retinal nerve fiber layer (RNFL) thickness, disorganization of inner retinal layers (DRIL), grade of retinal photoreceptor ellipsoid zone (EZ) disruption and grade of retinal pigment epithelium (RPE) alterations were evaluated using SD-OCT. Statistical analysis was done using ANOVA and Pearson's correlation analysis. RESULTS: Mean serum cortisol levels (µg/dL) were NPDR = 11.59 ± 0.42, PDR = 14.50 ± 0.26 and controls = 8.22 ± 0.77. With increasing severity of DR, mean CST, CAT, CV showed positive correlation, whereas mean RNFL thickness showed negative correlation with serum cortisol levels (p < 0.01). DRIL, EZ disruption and RPE alterations showed positive correlation with serum cortisol levels (p < 0.001). CONCLUSION: Serum cortisol levels are significantly associated with severity of DR and correlate positively with CST, CAT, CV, DRIL, EZ disruption and RPE alterations and negatively with RNFL thickness.

Disorganization of retinal inner layers correlates with ellipsoid zone disruption and retinal nerve fiber layer thinning in diabetic retinopathy.

PURPOSE: To study the correlation between disorganization of inner retinal layer (DRIL) and macular thickness parameters, ellipsoid zone (EZ) disruption and retinal nerve fiber layer (RNFL) thickness on spectral domain optical coherence tomography (SD-OCT) in diabetic retinopathy (DR), for the first time. METHODS: A tertiary care center-based cross-sectional study was undertaken. One hundred and four consecutive study subjects of type 2 diabetes mellitus were included: diabetes mellitus with no retinopathy (No DR) (n = 26); non-proliferative DR (NPDR) (n = 26); proliferative DR (PDR) (n = 26) and healthy controls (n = 26). Best Corrected Visual Acuity (BCVA) was measured on the logarithm of the minimum angle of resolution (logMAR) scale. Clinician-friendly, SD-OCT based, grading systems were created for DRIL and EZ disruption, within the macular cube. DRIL was graded as: grade 0, DRIL absent; and grade 1, DRIL present. EZ disruption was graded as; Grade 0: Intact EZ; Grade 1: Focal disruption and Grade 2: Global disruption. Every study subject underwent RNFL thickness analysis. RESULTS: DRIL was significantly associated with increase in severity of DR.Pearson correlation analysis showed significant positive correlation between DRIL and CST CAT and grades of EZ disruption . However, a significant negative correlation was found between DRIL and RNFL thickness . CONCLUSION: Presence of DRIL correlates with severity of DR, EZ disruption and RNFL thinning.

Understanding quality of life impact in people with retinal vein occlusion: a qualitative inquiry.

BACKGROUND: Although being the second most common sight-threatening retinal vascular disease after diabetic retinopathy, the patient-centred impact of retinal vein occlusion has not been well studied. This study aims to understand the quality of life issues in people with retinal vein occlusion using a qualitative methodology. METHODS: In-depth semi-structured interviews were conducted with 17 patients with retinal vein occlusion. All the interviews were digitally recorded and transcribed verbatim. An inductive analytic approach based on the constant comparative method was used for coding, aggregation, and theme development. The qualitative analysis was done using the software NVivo. RESULTS: Participants had a median age of 73 years (range 34-85 years; females, 71 per cent). Six quality of life themes were identified: concerns about the disease progression and treatment outcome (health concerns), emotional responses to the disease (emotional), experiencing a range of symptoms (symptoms), inability to do things as before (activity limitation), adapting to the visual loss (coping), and inconveniences due to the eye condition (convenience). Participants often felt that lasers and injections did not improve their vision. They feared that their eye condition may come back, or the other eye may be affected. They experienced a range of visual symptoms that affected their day-to-day performance, particularly reading small print, and driving at night. Having multiple treatments and frequent eye appointments were major sources of inconvenience. Patients adopted several coping strategies to manage the stress associated with visual loss. CONCLUSIONS: This study shows that several aspects of quality of life are compromised in people with retinal vein occlusion. The findings of this study will be used to identify the item content for a vitreoretinal disease-specific quality of life item bank.

Acute hypertensive uveitis as the first presentation of multiple sclerosis.

Ophthalmic manifestations of multiple sclerosis are frequent including acute optic neuritis, ocular motor disturbances and intermediate uveitis. We report an unusual case of multiple sclerosis presenting as acute hypertensive uveitis. A 56-year-old man was referred by his family doctor with a 2-week history of right eye pain and decreased vision. Best-corrected visual acuity was Count Fingers on the right and 6/9-2 on the left. Intraocular pressure was 55mmHg and 14 mmHg on the right and left respectively. He had a right relative pupillary defect and a left internuclear ophthalmoplegia. Vitreous cells were present in the right eye and there was peripheral sclerosis and periphlebitis superior temporally. MRI Brain and Spine revealed multiple T2 hyperintense lesions consistent with multiple sclerosis. Multiple sclerosis may present initially with an acute elevation of intraocular pressure and intermediate uveitis.

Central subfield thickness and cube average thickness as bioimaging biomarkers for ellipsoid zone disruption in diabetic retinopathy.

BACKGROUND: To evaluate the association of central subfield thickness (CST) and cube average thickness (CAT) with ellipsoid zone (EZ) disruption on spectral domain optical coherence tomography (SD-OCT) in patients of diabetic retinopathy (DR). METHODS: Cross sectional study including consecutive patients of type 2 diabetes mellitus [without DR (No DR, n = 97); non-proliferative DR (NPDR, n = 91); proliferative DR (PDR, n = 83)] and healthy controls (n = 82) was undertaken. CST and CAT values were measured using SD-OCT. Data was analyzed using Chi square test, ANOVA and multivariate analysis. Discriminant values of CST and CAT for EZ disruption were evaluated using receiver operator characteristic curve. Area under curve (AUC) was computed. RESULTS: Mean CAT and CST values in the study subjects showed an incremental trend. Multivariate ordinal logistic regression analysis showed increase in CST (OR = 1.022, p < 0.001) and CAT (OR = 1.029, p < 0.001) as significant independent predictors of EZ disruption. Area under curve showed excellent predictive results of CST (AUC = 0. 943 ± 0.021, 95% CI, 0.902-0.984, p < 0.05) and CAT (AUC = 0.959 ± 0.012, 95% CI 0.936-0.982, p < 0.05), as bioimaging biomarkers, for EZ disruption. CONCLUSION: Increase in CST and CAT is associated with increased odds of EZ disruption and these macular parameters serve as bioimaging biomarkers for EZ disruption in DR.

Visual outcomes following vitrectomy for diabetic retinopathy amongst Indigenous and non-Indigenous Australians in South Australia and the Northern Territory.

IMPORTANCE: Visual outcomes following diabetic vitrectomy have not previously been studied in an Australian population. BACKGROUND: This analysis aimed to determine the rate of, and factors associated with visual success following diabetic vitrectomy performed for Indigenous and non-Indigenous Australians, and investigate factors predisposing to early progression to diabetic retinopathy (DR) requiring vitrectomy. DESIGN: Retrospective, population-based audit. PARTICIPANTS: All patients undergoing vitrectomy for the complications of DR in South Australia (SA) and the Northern Territory (NT) between 2007 and 2011. METHODS: Medical records were audited and data collected, including demographics, diabetic history, past treatment for DR, indication for vitrectomy and visual acuity pre and postoperatively. MAIN OUTCOME MEASURES: Visual success (gain of ≥15 ETDRS letters) at 6 and 12 months, postoperatively. RESULTS: A total of 495 diabetic vitrectomies, for 404 eyes of 335 patients were performed in SA and NT between 2007 and 2011. 77 (23%) patients requiring diabetic vitrectomy were Indigenous Australians. 87% of patients undergoing diabetic vitrectomy had stable or improved vision at 1 year, postoperatively. There was no significant difference between indigenous and non-indigenous eyes achieving visual success (P = 0.929). Timely preoperative laser treatment (P = 0.03) and preoperative visual acuity (P = 0.01) were the predominant factors associated with visual success. CONCLUSIONS AND RELEVANCE: Indigenous patients are just as likely to have improved vision following diabetic vitrectomy as non-Indigenous Australians. However, the small subset of indigenous patients with blind eyes prior to vitrectomy are significantly less likely to improve from surgery. The underlying factors associated with poor outcomes in this group requires further exploration.

INCREASED SERUM LEVELS OF UREA AND CREATININE ARE SURROGATE MARKERS FOR DISRUPTION OF RETINAL PHOTORECEPTOR EXTERNAL LIMITING MEMBRANE AND INNER SEGMENT ELLIPSOID ZONE IN TYPE 2 DIABETES MELLITUS.

PURPOSE: To evaluate the role of serum urea and creatinine as surrogate markers for disruption of retinal photoreceptor external limiting membrane (ELM) and inner segment ellipsoid zone (EZ) in Type 2 diabetic retinopathy (DR) using spectral-domain optical coherence tomography, for the first time. METHODS: One hundred and seventeen consecutive cases of Type 2 diabetes mellitus (diabetes without retinopathy [No DR; n = 39], nonproliferative diabetic retinopathy [NPDR; n = 39], proliferative diabetic retinopathy [PDR; n = 39]) and 40 healthy control subjects were included. Serum levels of urea and creatinine were assessed using standard protocol. Spectral-domain optical coherence tomography was used to grade the disruption of ELM and EZ as follows: Grade 0, no disruption of ELM and EZ; Grade 1, ELM disrupted, EZ intact; Grade 2, ELM and EZ disrupted. Data were analyzed statistically. RESULTS: Increase in serum levels of urea (F = 22.93) and creatinine (F = 15.82) and increased grades of disruption of ELM and EZ (γ = 116.3) were observed with increased severity of DR (P < 0.001). Increase in serum levels of urea (F = 10.45) and creatinine (F = 6.89) was observed with increased grades of disruption of ELM and EZ (P = 0.001). CONCLUSION: Serum levels of urea and creatinine are surrogate markers for disruption of retinal photoreceptor ELM and EZ on spectral-domain optical coherence tomography in DR.

Aqueous Chlorhexidine for Intravitreal Injection Antisepsis: A Case Series and Review of the Literature.

PURPOSE: To determine the incidence of endophthalmitis in a large clinical series using aqueous chlorhexidine for antisepsis before intravitreal injection and to review the ophthalmic literature regarding chlorhexidine efficacy and safety. DESIGN: Multicenter retrospective case series. PARTICIPANTS: All patients receiving intravitreal injections from 7 retinal specialists. METHODS: An audit of intravitreal injections performed by retinal specialists who exclusively used aqueous chlorhexidine 0.05% or 0.1% for prophylaxis of infective endophthalmitis was undertaken. The incidence of endophthalmitis was determined from August 1, 2011, to February 28, 2015. A literature review was performed to critically appraise the ocular safety and efficacy of aqueous chlorhexidine. MAIN OUTCOME MEASURES: Incidence of endophthalmitis after intravitreal injections. RESULTS: A total of 40 535 intravitreal injections were performed by 7 retinal specialists across 3 centers. Chlorhexidine was well tolerated, and only 1 patient with a suspected allergic reaction was noted. Three cases of endophthalmitis were identified with 1 culture-positive case. The 0.0074% (1 in 13 512) per-injection rate of endophthalmitis in this series compares favorably with previous series in which povidone-iodine has been used. CONCLUSIONS: Aqueous chlorhexidine was associated with a low rate of postinjection endophthalmitis and was well tolerated by patients.

Spectral Domain Optical Coherence Tomography Features and Classification Systems for Diabetic Macular Edema: A Review.

Spectral domain optical coherence tomography (SD-OCT) is fast becoming the current standard of care for the detection and assessment of diabetic macular edema. With the application of SD-OCT for imaging of retinal microstructure and measurement of retinal thickness, new information regarding disease characteristics has been gathered, which was unrecognized previously. Retinal thickness measurements on SD-OCT have also been used for deciding the management and monitoring of the disease. Since its development, OCT has enhanced the understanding of retinal anatomical changes in diabetic retinopathy. Several authors have used SD-OCT to classify diabetic macular edema with the purpose of correlating the pathophysiology with disease severity. The classification systems have helped monitor the treatment efficacy and provide prognostic information on the treatment outcome. The following review article summarizes these classifications.

Antemortem vitreous potassium may strengthen postmortem interval estimates.

The purpose of this letter is to highlight that postmortem interval estimates using vitreous potassium concentrations may be further optimised by calibration against antemortem vitreous samples.

Biochemical analysis of the living human vitreous.

BACKGROUND: To date, our understanding of the biochemical composition of the living human vitreous relies on extrapolations from animal or human post-mortem studies. METHODS: This was a cross-sectional study of vitreous samples from 27 individuals scheduled for retinal surgery within a tertiary hospital. From each vitreous sample, the concentrations of sodium, potassium, chloride, calcium, magnesium, glucose, lactate, ß- hydroxybutyrate, copper, zinc, selenium, iron, ferritin and transferrin and osmolality were measured. Perioperative serum samples were also obtained for comparison. RESULTS: The following vitreous mean ± standard deviation (95% confidence interval of the mean) was observed for each analyte: sodium, 146.7 ± 3.3 (145.4-148.0) mmol/L; potassium, 5.73 ± 0.86 (5.39-6.08) mmol/L; chloride, 121.6 ± 2.6 (120.6-122.7) mmol/L; calcium, 1.128 ± 0.518 (0.923-1.333) mmol/L; magnesium, 0.900 ± 0.158 (0.838-0.962) mmol/L; glucose, 2.97 ± 0.98 (2.58-3.36) mmol/L; lactate, 3.97 ± 1.09 (3.54-4.40) mmol/L; osmolality, 289.5 ± 6.9 (286.6-292.5) mOsm/kg; BOHB, 0.0937 ± 0.0472 (0.0750-0.1124) mmol/L; copper, 0.519 ± 0.269 (0.412-0.625) µmol/L; zinc, 1.95 ± 1.09 (1.52-2.38) µmol/L; selenium, 0.1035 ± 0.0276 (0.0923-0.1146) µmol/L; iron, 3.11 ± 1.40 (2.56-3.66) µmol/L; ferritin, 19.5 ± 10.3 (15.5-23.6) µg/L; transferrin, 0.0878 ± 0.0526 (0.0670-0.1086) g/L. Vitreous biochemistry was not significantly different between male and female participants. Vitreous biochemistry was significantly different between non-diabetic and diabetic participants. Vitreous biochemistry was significantly different from the vitreous substitute BSS Plus (Alcon, USA). The vitreous extracted from living humans was markedly different from the commonly reported reference values obtained from animal studies. CONCLUSIONS: The current data provide hitherto unavailable information about the biochemical composition of the living human vitreous.

Rapid Resolution of Graft-versus-Host-Disease-Related Central Serous Chorioretinopathy.

We present a 23-year-old female patient who developed bilateral, multifocal CSCR three months after BMT and two months after developing GvHD. At the time of diagnosis, her medications included cyclosporine and high-dose oral steroid for GvHD. CSCR resolved quickly after the resolution of GvHD, along with rapid tapering of steroids and restoration of emotional wellbeing. Rapid tapering of systemic steroids under close monitoring of a hematologist in the setting of resolved mild GvHD may facilitate prompt resolution of CSCR.

Infrared reflectance as a diagnostic adjunct for subclinical commotio retinae.

Commotio retinae (CR) is an outer retinal disorder following blunt trauma to the eye. Histologically it is characterized by disruption of the photoreceptor outer segments (OS), typically without injury to other retinal layers. Using spectral-domain optical coherence tomography (OCT) the condition is visible as hyper-reflectivity of the OS. Most cases of CR are associated with transient grey-white discoloration of the retina and are easily diagnosed clinically, but there have been reports of OCT-confirmed CR without retinal discoloration. It is likely that this subclinical variant of CR is under-recognized as the OCT features of CR are subtle. Here, we report a case of OCT-confirmed subclinical CR that demonstrated prominent infrared hypo-reflectance, using the infrared protocol of the SPECTRALIS® OCT, Heidelberg Engineering. This case suggests that infrared reflectance may have a role in diagnosing cases of subclinical CR.