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Purpose: To analyze the topographic distribution of neovascularization (NV) and capillary nonperfusion (CNP) using ultra?wide field fluorescein angiography (UWFFA) in patients with proliferative diabetic retinopathy (PDR). Methods: This was a prospective, single?center, observational study in which all patients who presented between March 2019 and December 2020 and satisfied the inclusion criteria were recruited. In our study, patients with treatment?naïve PDR without any fibrovascular proliferation underwent UWFFA. The images were analyzed qualitatively for the topographic distribution of NV and the CNP area was quantified. The number of lesions picked by UWFFA was compared with 7 standard field (7SF) image using overlay of 7SF. The main outcome measure was characteristics of neovascularization, such as the number, location, and area of CNP, measured using UWFFA, which was considered with 95% confidence intervals (CI). Results: Two hundred and fifty?three eyes of 187 patients with a mean age of 56.03 ± 8 years were included. Mean neovascularization elsewhere (NVE) was 2.91 ± 3.43. Maximum NVEs were seen in the superotemporal (ST; 0.9 ± 1.13) quadrant, followed by the inferotemporal (IT; 0.7 ± 1.08), inferonasal (IN; 0.66 ± 1.02) and superonasal (SN; 0.66 ± 1.01) quadrants. Maximum CNP area was seen in the SN (13.75 ± 8.83 disc diameter square [DD2]) quadrant, followed by the IN (13.48 ± 8.59 DD2), IT (11.34 ± 8.37 DD2), and ST (11.3 ± 8.34 DD2) quadrants. Mean CNP area was maximum in patients with only neovascularization of disc (NVD; 64.99 ± 41.47 DD2), followed by both NVD and NVE (61.37 ± 35.61 DD2), and was minimum in patients with only NVE (36.44 ± 22.03 DD2). Eighty?one (32%) eyes out of 253 had NVE and 189 (75%) out of 253 had CNP area outside 7SF (overlay) of Early Treatment Diabetic Retinopathy Study (ETDRS). Conclusion: Diabetic NV lesions and CNP areas are distributed asymmetrically throughout the retina and are not restricted to the posterior pole. Compared to conventional 7SF imaging, UWFFA reveals significantly more retinal vascular pathology in patients with PDR.
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Purpose: To derive a formula for accurate axial length (AL) assessment using routine ultrasound in silicone oil?filled eyes, where optical biometry is unavailable or not possible. Methods: This was a prospective, consecutive, nonrandomized study of 50 eyes of 50 patients conducted in a tertiary care hospital in North India. AL measurements were taken using both manual A?scan and IOL master, both in silicone oil?filled status and 3 weeks after silicone oil removal. A correction factor of 0.7 was used for AL adjustment in oil?filled eyes. The corrected AL (cAL) was compared with IOL master values in oil?filled eyes. Agreement analysis was carried out using Bland Altman plot. Linear regression analysis was done using uncorrected manual AL to find a new equation. Data was analyzed using Stata 14. A P value <0.05 was taken as significant. Results: The study included 40 males and 10 females, with an age range of 6–83 years (mean 41.9 years). The mean AL of the oil?filled eye as measured by manual A?scan was 31.76 mm ± 3.09 and by IOL master was 24.7 mm ± 1.74. Linear regression analysis was performed in randomly selected 35 eyes of the observed data to obtain a new equation: predicted AL (PAL) = 14 + 0.3 × manual AL. The mean difference between PAL and optically measured AL with silicone oil in situ was 0.98 ± 1.67. Conclusion: We propose a new formula for better prediction of the correct AL in silicone oil?filled eyes using ultrasound?based AL measurement.
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Purpose: To study the long?term microvasculature changes at the macula and the optic disk in eyes with nonarteritic anterior ischemic optic neuropathy (NAION). Methods: Patients with acute NAION of less than 6 weeks duration were included. Optical coherence tomography angiography (OCTA) of the macula and the optic disk was performed at baseline, 3 and 6 months and compared with the controls. Results: The mean age of 15 patients was 52.25 (±9.06) years. The whole image superficial peripapillary density (42.49 ± 5.28) was significantly low when compared to that of control eyes (46.36 ± 2.09); similarly, radial peripapillary capillary density (49.35 ± 5.64) was also significantly reduced when compared to controls (53.45 ± 1.96, P < 0.05). These parameters showed significant progressive decrease at 3 and 6 months (P < 0.05). At the macula, both superficial (41.83 ± 3.64) and deep macular vasculature densities (47.30 ± 2.04) were significantly reduced when compared to control eyes (52.15 ± 4.84 and 55.13 ± 1.81, respectively). The vascular density at the macula remained stable at 3? and 6?months period. Conclusion: The study shows that the microvasculature in case of NAION is significantly reduced both in peripapillary area and in macular area.
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Purpose: To study the effect of subthreshold micropulse yellow laser treatment on central serous chorioretinopathy (CSC) and to compare two laser protocols. As per our knowledge, there are no studies comparing the two protocols of subthreshold laser. Methods: Twenty-three patients with non-resolving CSC of at least three months duration were treated with subthreshold laser (577 nm). Ten patients were treated with 5% duty cycle (group A) and 13 patients with 10% duty cycle (group B). At one month, best corrected visual acuity (BCVA), central macular thickness (CMT), subretinal fluid (SRF), choroidal thickness (CT) and choroidal vascularity index (CVI) were evaluated. Results: In group A, BCVA improved from 0.508 ± 504 to 0.174 ± 0.171 (P = 0.0058), CMT improved from 349.8 ± 168.9 micrometers (mm) to 183.3 ± 70.312 mm (P = 0.0093) and SRF reduced from 202.4 ± 158.024 to 43.8 ± 46.599 mm (P = 0.0069). In group B, BCVA improved from 0.437 ± 0.426 to 0.289 ± 0.470 (P = 0.0026), CMT improved from 280.846 ± 72.668 to 196.769 ± 72.62 mm (P = 0.0002) and SRF reduced from 110.385 ± 57.687 mm to 52.538 ± 52.111 mm (P = 0.0064). No significant difference was found in BCVA and CMT between the groups (P = 0.8716 and P = 0.8523, respectively). CSC completely resolved in 50% of cases in group A and in 69.2% of cases in group B. This difference was not statistically significant (0.423); however, the odds ratio of resolution was 2.25 times more with 10% duty cycle. No change was observed on fundus autofluorescence (FAF) following laser. Conclusion: Subthreshold micropulse laser can lead to resolution of SRF in 60.87% of cases (groups A and B combined). Ten per cent duty cycle had higher odds of resolution without causing any RPE damage.
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Purpose: To assess the macular vessel density (VD) on optical coherence tomography angiography (OCT?A) using proprietary software (automated) and image processing software (manual) in diabetic patients. Methods: In a retrospective study, OCT?A images (Triton, TOPCON Inc.) of type 2 diabetics presenting to a tertiary eye care center in North India between January 2018 and December 2019 with or without nonproliferative diabetic retinopathy (NPDR) and with no macular edema were analyzed. Macular images of size 3 × 3 mm were binarized with global thresholding algorithms (ImageJ software). Outcome measures were superficial capillary plexus VD (SCP?VD, automated and manual), deep capillary plexus VD (DCP?VD, manual), and correlation between automated and manual SCP?VD. Results: OCT?A images of 89 eyes (55 patients) were analyzed: no diabetic retinopathy (NoDR): 29 eyes, mild NPDR: 29 eyes, and moderate NPDR: 31 eyes. Automated SCP?VD did not differ between NoDR and mild NPDR (P = 0.69), but differed between NoDR and moderate NPDR (P = 0.014) and between mild and moderate NPDR (P = 0.033). Manual SCP?VD (Huang and Otsu methods) did not differ between the groups. Manual DCP?VD differed between NoDR and mild NPDR and between NoDR and moderate NPDR, but not between mild and moderate NPDR with both Huang (P = 0.024, 0.003, and 0.51, respectively) and Otsu (P = 0.021, 0.006, and 0.43, respectively) methods. Automated SCP?VD correlated moderately with manual SCP?VD using Huang method (r = 0.51, P < 0.001) with a mean difference of ?0.01% (agreement limits from ?6.60% to +6.57%). Conclusion: DCP?VD differs consistently between NoDR and NPDR with image processing, while SCP?VD shows variable results. Different thresholding algorithms provide different results, and there is a need to establish consensus on the most suited algorithm
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Purpose: Real?life comparison of three intravitreal drug regimens used in cases of endophthalmitis at a tertiary care center in India. Methods: In this prospective, comparative study, patients of bacterial endophthalmitis were grouped according to intravitreal antibiotic drug regimens into Group 1 (ceftazidime and vancomycin), Group 2 (piperacillin + tazobactam and vancomycin), and Group 3 (imipenem and vancomycin). Forty?eight hours after injection nonresponding/worsening patients underwent vitrectomy. Vitreous samples were subjected to microbiological and pharmacokinetic tests. Results: A total of 64 patients were included and divided into Group 1: 29, Group 2: 20, and Group 3: 15 cases. Also, 75% of patients were post?surgical endophthalmitis, whereas 25% were post?traumatic. Improvement in vision (V90?0) and vision at 3 months (V90) were comparable between the three groups. Visual recovery was poorer in post?traumatic cases. In post?surgical cases, visual recovery was poorer in those presenting beyond 72 h of onset of symptoms (P = 0.0002). Polymerase chain reaction (PCR) positivity (66%) was higher than BACTECTM (33%) and culture (14%). Antibiotic resistance was comparable amongst the three groups. Most patients (62/64) further underwent vitrectomy. Ceftazidime and vancomycin achieved vitreous concentrations more than the minimum inhibitory concentration (MIC) at 48 h after the first injection. Conclusion: The choice of antibiotics did not affect the rate of vitrectomy and final vision in a real?life scenario. Ceftazidime and vancomycin can still be used as first?line intravitreal antibiotics owing to their comparable microbial sensitivity profile and adequate ocular bioavailability
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Purpose: To determine and validate retinal vascular caliber measurements by using the confocal scanning laser ophthalmoscopy system. Retinal vasculature changes are often regarded as clinical markers for systemic disease. Methods: It was a prospective observational study conducted on 600 eyes of 300 normal subjects with no systemic or ocular illness from January 1, 2016 to June 30, 2017 in a tertiary referral eye center. Non?mydriatic infrared reflectance, blue reflectance, and blue peak blue autofluorescence fundus imaging were done on the confocal scanning laser ophthalmoscopy system. The dimensions of the retinal vessels were measured using inbuilt calipers at 1800 ?m from the center of the optic disc. Internal and external dimensions were measured. Observer variation and its comparison using Image J software were assessed. Results: The median age was 29 years (18–50 years). Mean internal and external diameters for arterioles were 85.1 ± 12.4 ?m and 105.0 ± 12.0 ?m, and for venules were 133.8 ± 16.6 ?m and 145.4 ± 16.1 ?m, respectively. The mean internal and external wall thicknesses were 19.7 ± 8.0 ?m and 11.0 ± 5.6 ?m, and wall thickness?to?lumen ratios were 0.3 ± 0.1 and 0.1 ± 0.1, respectively. Arteriolar?to?venular ratio for lumen and vessel was 0.66 ± 0.1 and 0.74 ± 0.1, respectively. There was no statistically significant difference between age groups. Both inter? and intra?observer reproducibility was >95%. The Bland–Altman plot showed that the difference between measurements using both confocal scanning laser ophthalmoscopy and Image J software lies within the limits of agreement approximately 95% of the time. Conclusion: This is the first effort to develop a normative database by using a simple non?invasive confocal scanning laser ophthalmoscopy system with high observer reproducibility
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BACKGROUND: The purpose of this study is to assess the utility of ocular ultrasound B scan in the emergency at the first point of care for detecting posterior segment and orbital pathologies in cases of paediatric ocular emergencies. METHODS: A prospective observational study involving 122 paediatric patients presenting to eye emergency over a period of ninety days were assessed with ultrasonography for the posterior segment as well as orbital pathology whenever indicated. The ocular ultrasound was performed gently over closed eyelids. RESULTS: Posttraumatic globe injuries were the most common indication for posterior segment evaluation, which constituted 80 (65.57％) eyes. Among these 52 patients had an anechoic posterior segment and 28 patients had variable findings such as vitreous haemorrhage (8.19％), retinal detachment (6.55％), choroidal detachment (4.91％), posteriorly dislocated clear lens (0.81％) and retained intraocular foreign body (5.73％). Non-traumatic cases constituted around 42 (34.42％) eyes, which included corneal ulcer (7.37％), retinoblastoma (6.55％), endophthalmitis (4.91％), extraocular muscle cysticercosis (4.91％), orbital cellulitis (4.09％), periocular haemorrhage (2.45％), proptosis(1.63％), paediatric cataract (1.63％) and cryptophthalmos (0.81％). No adverse events of performing the ultrasound was noted. CONCLUSION: First point ultrasonography in paediatric ocular emergencies is a cheap, portable and an effective tool in the assertion of significant posterior segment and orbital diseases.
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Purpose: The purpose of this study was to analyze the clinical profile of medicolegal cases (MLCs) presenting to the eye casualty in a tertiary care hospital. Materials and Methods: Retrospective review of records. The cases were grouped according to the Ocular Trauma Classification Group classification system. Results: Out of 188 MLCs, 164 (87.2%) were male. Mean age (±standard deviation) was 31.6 (±12.7) years. Age ranged from 7 to 75 years. Twenty‑six (13.8%) patients had bilateral involvement. The fist was the most common mode of injury, which was seen in 109 (58%) cases. A total of 27 (14.3%) patients had associated extraocular injury. No evidence of ocular or orbital trauma (malingering) could be found in 13 (7%) patients. Mechanical trauma was present in 169 (90%) patients with injury to globe in 129 (69%) patients and injury to lid or orbit without damage to the globe in 40 (21%) patients. Chemical injury was observed in 6 (3%) patients. Closed globe injury (CGI) was seen in 116 eyes and open globe injury (OGI) was noted in 29 eyes. The most common type of injury, zone, pupil, and grade of injury in CGI were Type A or contusion (79%), Zone I (72%), Pupil B (absence of relative afferent pupillary defect) in 95%, and Grade A [visual acuity (VA) ≥20/40] in 68% of the eyes, respectively. The most common type of injury, zone, pupil, and grade of injury in OGI were Type B or penetrating (48%), Zone II (38%), Pupil B (59%), and Grade D (VA 4/200‑light perception) (42%), respectively. Conclusions: The most common form and mode of ocular injury in MLC were closed globe injury and fist, respectively. The most common type of injury in CGI and OGI was contusion and penetrating injury, respectively.
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Apoptosis is a programmed and controlled form of cell death, which is distinct from necrosis. It is a non-inflammatory process and plays an important role in numerous physiological and pathological events. It has an indispensable role in the development and homeostasis in tissues of all higher organisms. Apoptosis can be identified by various methods such as electron microscopy, agarose gel electrophoresis, deoxyribonucleic acid fragmentation analysis, Tdt-dUTP terminal nick end labelling (TUNEL) assay, flow cytometry, annexin V staining and enzyme assays. A number of genes have been identified which are involved in this process. Many approaches for the control of apoptosis are being developed from the understanding of its molecular mechanisms. These include pharmacological inhibition or overexpression of the involved genes, gene therapy by viral transduction of apoptotic inhibitors, inhibition of proteases, inhibition of intracellular rise in calcium concentration and inhibition by scavenging mediators of apoptosis such as reactive oxygen species. In the eye, apoptosis seems to play a role starting from embryogenesis to diseases of all its components. Modulation of apoptosis using different inducers and inhibitors could be of great importance.