Study 3: Anterior segment optical coherence tomography-guided surgical approach in slipped medial rectus muscle

Purpose: To discuss the novel swept?source anterior segment optical coherence tomography (SS?ASOCT)?guided surgical approach in slipped medial rectus muscles. Methods: Prospectively (between February 2020 and July 2022), six patients with a clinical suspicion of slipped medial rectus muscle were recruited. After complete ophthalmic and orthoptic evaluation, the missing medial rectus muscle is screened using Anterior Segment Optical Coherence Tomography (ASOCT). In presence of a traceable muscle, its morphology, depth, and distance from a fixed anatomical landmarks were noted; in its absence, the status of other recti was noted. Intraoperatively, the features were confirmed and the intended intervention was performed. Results: The mean age of six patients was 25.66 ± 9.72 years, two with surgical trauma and four with penetrating trauma (66.66%). In five patients, the ASOCT traced the slipped medial rectus muscle successfully (83.33%); intraoperatively, the same was confirmed (within 1–2 millimeters) with favorable outcomes. ASOCT made a significant contribution in all subjects by reducing the number of interventions and muscle surgeries. Conclusions: In eyes with slipped medial rectus muscle, especially those which are within a finite distance from the angle can be traced using ASOCT. This approach impacts the outcomes in many ways

Anthropometry of deep-set eyes with respect to difficulty in docking during femtosecond laser procedures

Purpose: To identify the facial anthropometric parameters that predict the difficulty during femtosecond (FS) laser. Methods: This was a single?center observational study was conducted on participants between the ages 18 and 30 years who were planned for FS?LASIK (femtosecond laser?assisted laser in situ keratomileusis) or SMILE (small incision lenticule extraction) at Dr. Rajendra Prasad Centre for Ophthalmic Sciences, AIIMS, New Delhi, India. The front and side?facing images of the participants were analyzed using Image J software to measure different anthropometric parameters. The nasal bridge index, facial convexity, and other parameters were measured. The difficulty faced by the surgeon during docking was recorded for each subject. The data were analyzed on Stata 14. Results: A total of 97 subjects were included. The mean age was 24 (±7) years. Twenty?three (23.71%) subjects were females while the rest were males. Difficulty in docking was seen in 1 (4.34%) female and 14 (19%) males. The mean nasal bridge index was 92.58 (±4.01) in subjects with deep?set eyes and 89.72 (±4.30) in normal subjects. The mean total facial convexity was 129.28 (±4.24) in deep?set eyes, and 140.23 (±4.74) in normal subjects. Conclusion: Total facial convexity appeared as the most important feature, with the value being less than 133° in most subjects with unfavorable facial anthropometry

Intra-operative aberrometry versus conventional biometry for intraocular lens power calculation: A prospective observational study from a tertiary referral center

Purpose: To evaluate the per operative intra?ocular lens (IOL) power calculation using intra?operative aberrometry (ORA) and its comparison with conventional methods. Methods: Patients with cataract planned for phacoemulsification by a single surgeon under topical anesthesia were enrolled in this prospective observational study in this prospective observational study. All patients underwent pre?operative biometry (Manual SRK?II and IOLMaster® 500) to determine the intra?ocular lens (IOL) power. Intra?operative aberrometry using ORA was also performed; however, IOL was inserted according to IOLMaster® (SRK/T). Spherical equivalent (SE) was recorded on post?operative days 1, 7, and 30. Patients were divided into three groups based on axial lengths for analysis. Comparative analysis was performed for the calculated IOL powers and prediction errors of ORA with conventional methods. Adjusted IOL power to calculate the emmetropic IOL using the LiHue formula was also determined and was compared with existing methods. A P-value less than 0.05 was considered statistically significant. Results: A total of 115 eyes from 113 patients were included, with a median age of 54.90 ± 14.3 years. The mean axial length was found to be 23.94 ± 2.3 mm. There was good agreement (87%) between ORA and IOLMaster® for calculated IOL powers with a mean difference of 0.047 ± 0.5D between the two (P = 0.33). A positive correlation was found between IOL power calculated using ORA, IOLMaster®, SRK?II, and adjusted IOL. Conclusion: The use of intra?operative aberrometry (ORA) to calculate IOL power in patients undergoing uncomplicated phacoemulsification is non?inferior relative to standard pre?operative measurement and planning.

North India Childhood Cataract Study - The real scenario and causes of surgical delay of pediatric cataract

Purpose: The study sought to describe the clinical presentation pattern of pediatric cataracts and factors leading to delay in surgery at a tertiary care center in North India. Methods: A cross?sectional, interview?based study was conducted from January 2020 to October 2020, that included pediatric patients <12 years, with unilateral or bilateral congenital or developmental cataract. A pre?validated questionnaire was used to record data. The parameters recorded were age at first symptoms, age at diagnosis of cataract, age at surgery, laterality of cataract, first symptom, first family member noticing the abnormality, the morphology of cataract, association of perinatal complications, family history, systemic diseases, and cause (s) of delay in surgery. Results: A total of 89 patients were included. The mean age of subjects was 4.75(±3.51) years. A white pupil was the most common symptom (64.04%) and appeared in infancy in 30.3% of cases. Parents first detected the problem in 60.67%, and the pediatrician was the first medical contact in 11.23% of cases. The median (IQR) delay period between diagnosis of cataract and cataract surgery was 4 (3–6) months, the major causes were long GA waiting (30.33%), and delay due to systemic ill health (14.61%). Conclusion: Parental education on cataract detection is recommended to help in the timely detection and hence, improved outcomes of pediatric cataract surgery. Pediatricians, consulted for any systemic illness, have the role of the second most important contact in the detection of pediatric cataract.

Scleral tunnel phacoemulsification: Approach for eyes with severe microcornea.

Cataract surgery in eyes with microcornea is associated with frequent complications such as corneal edema, posterior capsular rent, and risk of unplanned aphakia. We describe an improved surgical technique for the creation of surgical incisions during phacoemulsification in eyes with cataract associated with microcornea. A retrospective analysis of eight patients (8 eyes) operated at our center was undertaken. The mean age of the patients was 29.5 ± 10.9 years. All eyes were operated using the scleral pocket incision for phacoemulsification. This scleral pocket incision was tangential to the limbus and created approximately 2.5 mm behind limbus through which phacoemulsification probe was inserted. Because of the posterior placement of incision, the anterior chamber crowding was minimized. There was no incidence of port‑site peripheral corneal edema. Fifty percent eyes developed transient central corneal edema, the intraocular lens in bag was implanted in 5/8 eyes, and none developed Descemet’s membrane detachment. Mean best‑corrected visual acuity improved from 1.85 ± 0.38 logarithm of minimum angle of resolution (LogMAR) to 1.26 ± 0.70 LogMAR postoperatively (P = 0.01; paired t‑test). Posterior incision placement during phacoemulsification in microcornea helps achieve favorable postoperative outcomes in contrast to outcomes using clear corneal approach described in literature.

Changes in stereoacuity following implantable Collamer lens implantation in patients with myopia.

The study evaluated the impact of implantable Collamer lens (ICL) implantation on stereoacuity in myopes in a retrospective case series. Ninety‑five eyes of 48 patients were recruited. Distance and near stereoacuity were measured using distance Randot stereotest and TNO test, respectively, before surgery and at 4 weeks postoperatively. Mean age of the patients was 23.67 ± 3.7 years. Mean uncorrected distance visual acuity (UDVA) was 1.28 ± 0.37 logarithm of the minimum angle of resolution (logMAR) (median: 1.3; range: 0.3–1.8), and median best‑corrected distance visual acuity (BDVA) was 0.18 logMAR (range: 0–0.6). There was a significant improvement in both UDVA and BDVA postsurgery (P < 0.001; Wilcoxon signed rank test). The overall improvement in stereopsis was observed in 15/48 (31.25%) and 13/48 (27.10%) subjects for near and distance, respectively, with no significant difference between the two (P = 0.82; Fisher’s exact test). Among stereoblind individuals, the odd’s ratio for near stereoacuity to improve in comparison to distance stereoacuity was 8.85 (95% confidence interval: 1.68–46.70; P = 0.01). ICL implantation for refractive correction aided stereoacuity improvement in myopes more so for near.

Ahmed glaucoma valve in post-penetrating-keratoplasty glaucoma: A critically evaluated prospective clinical study.

Aim: The aim was to evaluate the outcome of Ahmed glaucoma valve (AGV) in post-penetrating-keratoplasty glaucoma (PKPG). Materials and Methods: In this prospective study, 20 eyes of 20 adult patients with post-PKPG with intraocular pressure (IOP) >21 mmHg, on two or more antiglaucoma medications, underwent AG (model FP7) implantation and were followed up for a minimum of 6 months. Absolute success was defined as 5 <IOP <21 mmHg and qualified success as 5 <IOP <21 mmHg with medications or minor procedures. Results: The mean IOP decreased from 42.95 ± 10.24 to 17.69 ± 3.64 mmHg (P <0.001) and the use of medications dropped from 2.92 to 0.39 (P <0.001) after AGV implantation. The absolute success was achieved in 11 eyes and qualified success in 9. There was no significant change in best corrected visual acuity, graft clarity, or graft thickness. Six device-related complications occurred after AGV implantations which were successfully managed with medical or minor surgical therapy. Conclusions: Postkeratoplasty refractory glaucoma managed by AGV implantation revealed a satisfactory outcome up to 6 months of follow-up.

Visual outcome after intravenous dexamethasone therapy for idiopathic optic neuritis in an Indian population: a clinical case series.

PURPOSE: To evaluate the clinical profile, response to dexamethasone treatment and visual function outcome in Indian patients with acute optic neuritis. MATERIALS AND METHODS: We conducted an observational study of patients with acute optic neuritis who were treated with intravenous dexamethasone (100 mg in 250 ml of 5% dextrose over 1-2 hours daily, for three consecutive days) and had completed at least two years of follow-up. Parameters assessed included visual acuity, contrast sensitivity, color vision, visual fields, relative afferent pupillary defect (RAPD) and visually evoked potentials. Out of 40 patients studied, 26 patients (33 eyes) had all visual function parameters assessed. Twenty three patients (28 eyes) had completed two years of follow-up and were included for statistical analysis. RESULTS: Improvement in visual acuity was statistically significant for distance after 24 hours of the first dose (P = < 0.001) and for near vision after 24 hours of the second dose (P = 0.006); improvement in color and contrast sensitivity was statistically significant 24 hours after the third dose (P = < 0.001 for color vision and P = 0.013 for contrast sensitivity). Significant improvement in RAPD and visual fields were seen by 1 month (P = 0.005). Recurrence was seen in 4 eyes of 4 patients. No serious side effects were observed. At two years, 82.14% (23 out of 28) eyes had visual acuity > 20/40. CONCLUSION: Treatment with intravenous pulsed dexamethasone led to rapid recovery of vision in acute optic neuritis, without any serious side effects.

Comparative evaluation of Teller and Cardiff acuity tests in normals and unilateral amblyopes in under-two-year-olds.

PURPOSE: To compare and evaluate Teller Acuity Cards (TAC) and Cardiff Acuity Cards (CAC) to assess vision in children below the age of two. METHODS: The study evaluated TAC and CAC to assess visual acuity in 90 normal children divided into three age groups, 0-6 months (group I), 6-12 months (group II) and 12-24 months (group III). 30 cases of unilateral amblyopiogenic conditions, 10 cases each of unilateral refractive error, unilateral esotropia, and unilateral cataract, were also examined. Trained optometrists carried out binocular testing followed by monocular testing, and recorded the test time in each case. RESULTS: The mean visual acuity (in Snellen units) and standard deviation (in octaves) in the three age groups of normal children, I, II, III respectively were 6/44 +/- 0.54, 6/21 +/- 0.37 and 6/21 +/- 0.41 (binocularly by TAC) and 6/46 +/- 0.80, 6/21 +/- 0.59 and 6/14.5 +/- 0.84 (binocularly by CAC). Although the time taken for testing with CAC was less, its coefficient of variance was greater for all age groups as compared to TAC. Diminution of visual acuity could be assessed correctly by both the tests in cases of strabismus and cataract, but not in some cases of refractive error. CONCLUSION: CAC is a useful and child-friendly test. It can be used clinically but may miss some cases of visually significant refractive errors. TAC is a more dependable test to assess amblyopiogenic conditions despite the use of gratings.

Apoptosis: an ocular perspective.

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.