Comparative evaluation of OCT with OCTA changes at the optic disc and macula in glaucoma suspect and early glaucoma.

PURPOSE: To compare the diagnostic ability of macular ganglion cell inner plexiform layer (mGCIPL) and peripapillary retinal nerve fiber layer (pRNFL) thickness on optical coherence tomography (OCT) and macular and peripapillary perfusion changes using OCT angiography (OCTA) in glaucoma suspect and early primary open angle glaucoma (POAG). METHODS: Ninety patients (30 normal, 30 glaucoma suspects, and 30 early POAG) were recruited in this cross-sectional, prospective study. The average thickness of mGCIPL and pRNFL on spectral domain-OCT and macular vessel density (VD), optic nerve head (ONH) perfusion, and ONH flux index (FI) on OCTA were evaluated for early diagnosis of glaucoma. RESULTS: Macular VD, ONH perfusion, and ONH FI were significantly reduced in early POAG eyes compared to normal. The best correlation was observed between ONH FI and the average RNFL in both glaucoma suspects (r = 0.47, P < 0.01) and early POAG patients (r = 0.53, P < 0.01). Out of all the measured OCTA parameters, only ONH perfusion was significantly lower in glaucomatous eyes compared to glaucoma suspects (P < 0.001). Average GCIPL (0.82) and macular VD (0.76) had the highest area under the receiver operating characteristic (AUROC) curve value among all the OCT and OCTA parameters, respectively, for differentiating glaucoma suspects from controls. Rim area (0.92) and ONH FI (0.81) had the highest AUROC value among all the OCT and OCTA parameters for differentiating early POAG patients from controls. CONCLUSION: OCTA vascular parameters had a good correlation with structural damage both at the disc and the macula. OCT parameters were superior to OCTA parameters for diagnosis of glaucoma, although OCTA parameters are deranged very early in the disease.

Scleral buckling in retinal detachment due to retinal dialysis - A vitreoretina fellow's perspective.

PURPOSE: To analyze the efficacy of scleral buckling in the hands of vitreo-retina (VR) fellows under training in eyes with retinal detachment associated with retinal dialysis and analyze the patient and retinal characteristics in these eyes. METHODS: We carried out a retrospective consecutive case review at a tertiary eye care center in North India. Records of all the patients who had undergone scleral buckling (SB) for retinal dialysis-associated rhegmatogenous retinal detachment by VR fellows (with less than 2 years' experience) between January 2017 and January 2020 were reviewed. RESULTS: Fifty-three eyes of 53 patients with a mean age of 20.77 years were analyzed. Of the patients, 73.58% were males. History of eye trauma was present in 71.69% patients. A total of 21 residents operated these 53 eyes. SB was able to achieve retinal attachment in a single surgery in 84.9% (45/53) eyes. Mean preoperative best corrected visual acuity was 1.9 ± 1.05 log of minimum angle of resolution (logMAR), which improved postoperatively to 1.07 ± 0.72 logMAR (P < 0.001). Surgical success rate was 85.71% (24/28) in eyes with no proliferative vitreoretinopathy (PVR), 66.66% (2/3) in eyes with PVR-A, 91.66% (11/12) in eyes with PVR-B, and 80% (8/10) in eyes with PVR-C1. Fifty-two eyes had a single dialysis and one eye had two separate dialysis. Six eyes had giant retinal dialysis (dialysis greater than 3 clock hours) and all were due to trauma. Five patients had retinal dialysis in the fellow eye and were diagnosed with bilateral idiopathic retinal dialysis. CONCLUSION: Scleral buckling is a safe and effective management for retinal dialysis retinal detachment even in the hands of VR fellows under training.

Comprehensive review of angioid streaks.

ABSTRACT: Angioid streaks are irregular breaks in the brittle Bruch's membrane and commonly present as pigmented linear lines radiating from the optic disc. They may be associated with systemic disease in up to 50% of the patients. Systemic diseases such as pseudoxanthoma elasticum, Paget's disease, and hemoglobinopathies are commonly associated with angioid streaks. However, they may be idiopathic in a small number of cases. Patients may be asymptomatic until complications such as choroidal neovascular membrane and subretinal hemorrhage involving the fovea develop. Due to the brittle nature of Bruch's membrane, even minor trauma could lead to subretinal hemorrhage in these eyes. Diagnosis is commonly made through clinical examination and investigations such as fundus autofluorescence and optical coherence tomography. Treatment consists of management of the choroidal neovascular membrane commonly through intravitreal antivascular endothelial growth factor injections. In this review, we provide an overview of angioid streaks right from their epidemiology to their management.

Evaluation of peripheral retinal degenerations using ultra-widefield swept source optical coherence tomography.

PURPOSE: To describe the features of peripheral retinal degenerations using an Ultra-Widefield (UWF) Swept Source Optical Coherence Tomography (SS-OCT). METHOD: In this cross-sectional study done at a tertiary eye care centre in Northern India, peripheral retinal degenerations such as lattices, snail track lesion, paving stone, White With-Out Pressure(WWOP), micro-cystoid lesions, retinoschisis and other suspicious lesions were identified with clinical examination. Following clinical examination, these eyes with peripheral retinal degenerations underwent UWF OCT. RESULTS: 100 eyes with 14 peripheral lesions like lattices (31%), snail track lesions (10.4%), peripheral retinoschisis (7.5%), non-specific pigmented doubtful lesions (13.2%), WWOP (7.5%), paving stone (6.6%), peripheral retinal detachment (3.8%) along with CHRPE, micro-cystoid lesions and dark without pressure areas were identified. All the lesions could be imaged with the help of UWF-OCT. It significantly helped in improving diagnostic capability with early identification of specific structural features such as vitreoretinal attachment and traction, full-thickness hole or tear, and sub-retinal fluid which were not so evident on indirect ophthalmoscopy. CONCLUSION: UWF-OCT deepens our understanding of the structure of the retina and its associated peripheral pathologies, allowing early recognition of vision-threatening lesions that may influence clinical management.

Vitrectomy for cases of diabetic retinopathy.

ABSTRACT: Microvascular complications of diabetic retinopathy (DR) may require surgical intervention in the form of vitrectomy. Since its inception, diabetic vitrectomy has evolved with introduction of better instruments, newer techniques, and smaller port sizes. Common indications for diabetic vitrectomy include nonresolving vitreous hemorrhage, tractional retinal detachment, epiretinal membrane, progression of fibrovascular membranes despite laser therapy, recalcitrant diabetic macular edema, and neovascular glaucoma. Preoperative systemic stabilization is essential prior to planning surgery. Surgical techniques commonly used in diabetic vitrectomy are segmentation, delamination, and rarely en-bloc dissection. Modification in surgical techniques such as chandelier-assisted bimanual dissection and pharmacological adjuvants improve surgical outcomes in these patients. Prognosis in these patients could be improved with early intervention. Studies evaluating the outcome of vitrectomy in patients with early proliferative DR are required to understand the appropriate time of intervention in patients. Treatment aimed at arresting the progression of DR and gene therapy are avenues that need further evaluation. The following review will focus on covering the epidemiology of DR, indications of vitrectomy, preoperative considerations, surgical procedures of diabetic vitrectomy, methods of membrane dissection, pharmacological adjuvants to vitrectomy, outcomes of diabetic vitrectomy, and future directions of diabetic vitrectomy.

Bilateral peripapillary choroidal neovascular membranes in Vogt-Koyanagi-Harada disease.

Choroidal neovascular membrane (CNVM) in Vogt-Koyanagi-Harada disease (VKH) is a known entity, observed primarily during the chronic convalescent and chronic-recurrent phases of the disease. However, the peripapillary location of CNVM is a rare finding.We describe a case of chronic VKH with bilateral peripapillary CNVM detected using multimodal imaging and the associated differential diagnoses and treatment approach.A combination of anti-vascular endothelial growth factor injections, systemic steroids and immunosuppressants is often required to manage the aggressive course of this choroidal neovascularisation.

Correlation Between Optical Coherence Tomography Angiography Findings at 3 to 6 Weeks and Functional Outcome at 3 Months Following Acute Ischaemic Stroke Due to Extracranial Carotid Artery Atherosclerotic Disease.

We wanted to evaluate if optical coherence tomography angiography OCTA findings could predict the functional outcome in extracranial carotid artery atherosclerotic disease (ECAD) associated stroke. This exploratory study was performed on adults with acute ischaemic stroke due to ECAD at 3-6 weeks following stroke onset with risk factor matched controls without carotid artery stenosis. Twenty-three stroke patients (cases) and 23 controls were enrolled. There was significant difference between cases and controls in deep vessel density at the macula (p = .0007) and in radial peripapillary capillary perfusion density (RPCPD) at the optic nerve head (ONH) (p = .0007). Statistically significant difference was noted in the total superficial vessel density (SVD) at the macula (SVD within 1 standard deviation [SD] versus SVD beyond 1 SD of control data) in the ipsilateral eye and functional outcome at 3 months (poor versus very good outcome, modified Rankin scale [mRS] 0-1 versus mRS 2-6, respectively; p = .0361). There was statistically insignificant correlation between the RPCPD at the ONH and the National Institutes of Health Stroke Scale score at admission, mRS at discharge, and mRS at 3 months following stroke onset (r = .33, r = .35, r = .39; p = .11, p = .09, p = .06, respectively). The findings of this exploratory study suggested that OCTA findings may predict 3 month outcomes in cases of ECAD-related stroke and could be useful in decision making in future intervention studies as to whether intervene or not in patients having critical or non-critical ECAD for preventing stroke.

Dysregulated Th17/Treg cell axis is correlated with local and systemic immune response in human intermediate uveitis.

Th17/Treg cell balance is essential for immune homeostasis and when disrupted, is associated with the occurrence and development of inflammation in numerous autoimmune diseases. However, its contribution in pathophysiology of uveitis remains unexplored. In this study, we deciphered the role of Th17/Treg cell balance in autoimmune uveitis subjects. Using flow cytometry, we detected the frequencies and absolute count of both Th17 and Treg cells in the aqueous humor and peripheral blood of patients and healthy controls. Our results for the first time reveal a significant increase (p < 0.01 and p < 0.005) in Th17 population alongside a significant decrease (p < 0.001 and p < 0.003) in Treg cell population in both the aqueous humor and PBMCs of uveitis patients. Further we analyzed the expression of Th17-Treg associated genes and cytokines via qPCR and ELISA respectively. These findings align with our flow cytometry results, as evident by a significant (p < 0.002) up-regulation of IL-17 and a concurrent down regulation of IL-10 at transcriptional levels. Moreover, IL-17A cytokine was found to be substantially high (p < 0.001) and IL-10 (p < 0.02) down regulated in serum. Interestingly, we demonstrated a significant correlation of Th17/Treg cells in aqueous humor with those in peripheral blood. Conclusively, our results suggest the pivotal role of Th17/Treg cell axis in the immuno-pathophysiology of human uveitis. Further we propose the therapeutic potential of targeting this novel axis for ameliorating the disease burden associated with uveitis.

Follow-up report of fundus findings of tuberous sclerosis-associated retinal astrocytoma of two siblings.

A late adolescent with tuberous sclerosis (TS) presented with reduced vision in one eye to our tertiary care university hospital 4 years ago. Fundus examination revealed multiple retinal astrocytic hamartomas (RAHs) in both eyes. His younger sibling, who also had TS, was found to have RAH on retinal screening. The swept-source optical coherence tomography (SS-OCT) findings were typical of RAH. We further noted that some of the RAH lesions showed segmental whitening of the outer walls of the arterioles, which traversed through them. The segmental whitening may suggest the enveloping of normal retinal vessels by the tumour. En-face and B-scan SS-OCT angiography of patients with TS showed vascularity within the tumour. The vessels within the tumour appeared to be in continuity with the retinal vasculature. Both siblings were reviewed annually. At the end of 4 years, there was no change in visual acuity, tumour size, number, vascularity and behaviour.

Atypical acquired toxoplasmosis.

A 33-year-old male presented with unilateral painless vision loss with a history of sub-tenon steroid for the same. The fundus showed an elevated focus of retinochoroiditis with vitritis. On investigating for the cause, polymerase chain reaction test on the anterior chamber tap was found to be positive for Toxoplasma. Such confusing and atypical cases usually produce a clinical dilemma and should be managed in a stepwise manner. Ancillary investigations usually provide a clue to the clinician and should be performed without any hesitation.