BEST1 associated bestrophinopathies with angle closure and post-surgical malignant glaucoma.

INTRODUCTION: Mutations in BEST1 gene have been linked to the development of refractory angle closure glaucoma (ACG). This study aims to delineate the clinical characteristics, genetic mutations, and disease progression in patients with autosomal recessive bestrophinopathy (ARB) and autosomal dominant Best vitelliform macular dystrophy (BVMD) who are presented with treatment-resistant ACG. METHODS: This retrospective analysis encompasses a comprehensive ophthalmic assessment, retinal imaging, and mutational profiling of six patients diagnosed with bestrophinopathy and concurrent ACG, with a particular emphasis on the risk of post-glaucoma filtration surgery malignant glaucoma (MG). Exome sequencing was conducted utilizing a next-generation sequencing (NGS) based gene panel. RESULTS: The cohort included five patients with ARB and one with BVMD, with a mean (±SD) age at ACG diagnosis of 35.1 ± 6.9 years. NGS analysis revealed homozygous BEST1 variants in four patients (ARB; cases 1-4) and a heterozygous BEST1 variant in one patient (BVMD; case 5). One patient (ARB; case 6), despite a recessive pedigree, showed a single heterozygous variant, suggesting the presence of an undetected heterozygous variant indicative of compound heterozygous autosomal recessive inheritance. A novel non-frameshift deletion (c.841_843delTTC; p.Phe281del) was identified in case 2. Surgical intervention was required due to uncontrolled glaucoma in all cases except case 4. All five cases that underwent glaucoma filtration surgery developed MG, which was effectively managed with combined iridozonulo-hyaloido-vitrectomy (IZHV) and pars plana vitrectomy (PPV). Cases 5 and 6, harboring a heterozygous pathogenic variant (c.241 G>A; p.Val81Met), experienced refractory MG and corneal decompensation necessitating multiple interventions. CONCLUSION: Genomic analysis plays a pivotal role in the management of bestrophinopathies with ACG. Characterization of mutational types facilitates prognostication and enables timely interventions. IZHV with PPV emerges as a promising standalone or adjunctive procedure for the management of glaucoma among patients with BEST1 mutations and ACG.

Learning Curve in Posterior Segment Ophthalmic Diagnostic Endoscopy: Implications for Budding Enthusiasts and Fellows-In-Training.

PURPOSE: To elucidate the learning curve for posterior segment diagnostic endoscopy (DE) based on the results of a self-trained (ST) and a supervised (SUP) vitreoretinal surgeon. METHODS: Retrospective review of medical records of DE performed between 2017 and 2023 by one ST and one SUP vitreoretinal surgeon at a tertiary eye care institute. Data were collected and the serial number of cases was plotted against the time taken for the procedure. A comparative regression plot was created for both the surgeons to know the slope of the learning curve. The start time was noted as that of attachment of the endoscope and the stop time was noted as the end of diagnostic evaluation. Procedures were divided into blocks of 10 cases each and the time taken for the procedures was calculated. RESULTS: Total of 106 eyes (58 by ST surgeon and 48 by SUP surgeon) were included. For ST surgeon, the time taken for the surgery correlated inversely (reduced sequentially) with the serial number of the case till the 20th case (correlation coefficient = -0.5, p = .01), for SUP surgeon, the time taken for the surgery correlated inversely with the serial number of the case till the 10th case (correlation coefficient = -0.9, p = <0.0001) and then stabilized. Neither of the groups had any adverse events. CONCLUSION: About 20 cases for a self-trained and about 10 cases for a supervised vitreoretinal surgeon are required to get stable with DE. These observations have implications in creating a training module for DE with appropriate number of training cases.

Peripheral defocus of monofocal intraocular lenses.

PURPOSE: To quantify the angular dependence of monofocal intraocular lens (IOL) power. SETTING: Ophthalmic Biophysics Laboratory, Kallam Anji Reddy campus, L V Prasad Eye Institute, Hyderabad, India. DESIGN: Laboratory study. METHODS: Experiments were performed on IOLs from 2 different manufacturers (APPALENS 207, Appasamy Associates and SN60WF, Alcon Laboratories, Inc.). IOL powers ranged from 17 to 25 diopters (D). The IOLs were mounted in a fluid-filled chamber, and the on-axis and off-axis powers were measured using a laser ray tracing system over the central 3 mm zone with delivery angles ranging from -30 to +30 degrees in 5-degree increments. The position of the best focus was calculated for each IOL at each angle. The angular dependence of IOL power was compared with theoretical predictions. RESULTS: Peripheral defocus increased significantly with increasing incidence angle and power. The peripheral defocus at ±30 degrees increased from 5.8 to 8.5 D when the power increased from 17.5 to 24.5 D for APPALENS 207 and from 4.9 to 7.4 D when the power increased from 17 to 25 D for SN60WF. The mean difference between the measured and theoretical tangential power at ±30 degrees was 0.50 ± 0.16 D for the APPALENS 207 and -0.40 ± 0.10 D for the SN60WF, independent of IOL power. CONCLUSIONS: IOLs introduce a significant amount of peripheral defocus which varies significantly with IOL power and design. Given that peripheral defocus is related to lens power, replacement of the crystalline lens (approximately 24 D) with an IOL will produce a significant difference in peripheral defocus profile after surgery.

Refractive outcomes following silicone oil tamponade in vitreoretinal surgery.

PURPOSE: To evaluate the factors influencing the refractive outcomes following silicone oil tamponade (SOT) and silicone oil removal (SOR) in different lens statuses post-vitreoretinal surgery. DESIGN: Retrospective analysis of three different lens statuses. MATERIALS AND METHODS: This was a descriptive study that included 150 eyes of 147 patients who had undergone pars plana vitrectomy with SOT and SOR between January 2017 and June 2021. Demographic profile, spherical equivalent refraction (SER), and its association with clinical features were evaluated with SOT and post-SOR. RESULTS: The mean (±standard deviation [SD]) age was 47 ± 17.8 years, including all three groups. SER was represented in diopters (D). The mean ± SD refraction with SOT in phakic, pseudophakic, and aphakic was 4.28 ± 2.59 D, 2.94 ± 2.58 D, and 3.98 ± 4.82 D. The mean SER post-SOR in phakic, pseudophakic, and aphakic was -2.72 ± 2.03 D, -1.12 ± 1.41 D, and 8.22 ± 3.70 D. The diagnosis of rhegmatogenous retinal detachment (RRD) among 96 eyes (64%) is the common indicator to perform vitreoretinal (VR) surgery. A minority of subjects were managed with retinal lasers before VR surgery (14%). The macula was attached in 100 eyes (67.6%), the belt buckle was done in 37 eyes (24.7%), and the silicone oil viscosity with 1000 centistoke was chosen in 129 eyes (86%). CONCLUSION: SOT was used as a tamponade in VR surgeries irrespective of lens status. The significant predictor for post-SOR refraction in phakic and aphakic is post-SOT refraction. In pseudophakic, gender and diagnosis of RRD are the predictors of SOR refraction.

Outcomes of vitreoretinal surgery in eyes with retinitis pigmentosa without retinal detachment.

PURPOSE: Outcomes of retinal detachment (RD) have been discussed in detail in many reports of patients with retinitis pigmentosa (RP). This study tries to understand the outcomes of vitreoretinal (VR) surgery for indications other than RD in the eyes with RP. METHODS: This is a retrospective study that includes clinical data from January 2013 to December 2021. Patients with RP who were treated with a VR surgical intervention were included in the study. The primary outcome of the study was to assess the changes in best-corrected visual acuity. RESULTS: Forty-four eyes of 40 patients with RP were included in the study. Nearly half of the eyes (43%, 19/44) presented from 1 month to 1 year after the onset of diminished vision, with or without floaters. The mean ± standard deviation (SD) best-corrected visual acuity (BCVA) at presentation was 1.30 ± 0.79 logMAR (20/400 ± 20/125). The major surgical indications were vitreous opacities (43.2%, 19/44) and subluxated/dislocated cataractous lenses (25%, 11/44). The median follow-up duration was 8 months (interquartile range (IQR): 1.5-27). Approximately 77% (34/44) of the eyes had improvement in vision. The mean postoperative BCVA at the last follow-up was 0.95 ± 0.73 logMAR (p-value: 0.03). CONCLUSIONS: Most eyes with RP recovered well after VR surgical interventions, with short-term improvements in visual acuity. It may be crucial to address the vitreous opacities and membranes as they hinder the residual central island of vision in RP. However, appropriate counselling is required regarding the progressive nature of retinal neuronal degeneration.

Prognostic factors for visual outcome after surgical repair of limbal corneal laceration at a tertiary eye care center in South India.

Purpose: To determine the factors affecting the visual outcome after surgical repair of limbal corneal lacerations at a tertiary eye care center in South India. Methods: A retrospective analysis of patients diagnosed with limbal tears between 2011 and 2021 was conducted. Demographic information such as age, gender, cause of injury, and size of the laceration was recorded. Comprehensive ocular examination was performed, including gentle B scan evaluation whenever not contraindicated for detailed posterior segment evaluation. Only those cases with a minimum follow-up of one year were included. Postoperative best-corrected visual acuity, intraocular pressure (IOP), cornea clarity, and integrity of the wound at last follow-up were noted. Results: Out of the 20 patients, 15 (75%) were males and 5 (25%) were females. The mean age was 42.6 ± 22.4 years. All 20 patients had a penetrating injury, with four (20%) injured by a stick, two (10%) by an iron rod, three (15%) due to road traffic accident (RTA), three (15%) by glass, and eight (40%) with other nonspecific objects [two (10%) with needle, two (10%) with elastic rope, two (10%) with bangle, and two (10%) with metal]. The average time between the injury and the surgery was 48 hours (2 days). Four (20%) patients underwent a second surgery within a week of repair. After limbal tear repair, at final follow-up at 3 years, 7 (35%) had VA worse than 20/800, 3 (15%) had VA between 20/100 and 20/800, and 10 (50%) achieved VA better than 20/80. Conclusion: Preoperative visual acuity (VA), mode of injury, and size of wound affect the final visual outcome after surgical repair of limbal corneal laceration. Preoperative VA and mode of injury were statistically significant even in the multivariate analysis.

Gastrointestinal mucormycosis in a child with acute lymphoblastic leukemia: An uncommon but ominous complication.

Invasive fungal infections constitute a major cause of morbidity and mortality in children undergoing therapy for hematological malignancies. We report a 1-year-old boy who was receiving chemotherapy for acute lymphoblastic leukemia. His clinical course was complicated by a clinical syndrome consistent with neutropenic enterocolitis to which he succumbed. Histopathology of the surgically resected bowel revealed evidence of mucormycosis. Gastrointestinal mucormycosis is an unusual presentation which requires high degree of clinical suspicion and aggressive management.

Discrete Responses to Limitation for Iron and Manganese in Agrobacterium tumefaciens: Influence on Attachment and Biofilm Formation.

UNLABELLED: Transition metals such as iron and manganese are crucial trace nutrients for the growth of most bacteria, functioning as catalytic cofactors for many essential enzymes. Dedicated uptake and regulatory systems have evolved to ensure their acquisition for growth, while preventing toxicity. Transcriptomic analysis of the iron- and manganese-responsive regulons of Agrobacterium tumefaciens revealed that there are discrete regulatory networks that respond to changes in iron and manganese levels. Complementing earlier studies, the iron-responsive gene network is quite large and includes many aspects of iron-dependent metabolism and the iron-sparing response. In contrast, the manganese-responsive network is restricted to a limited number of genes, many of which can be linked to transport and utilization of the transition metal. Several of the target genes predicted to drive manganese uptake are required for growth under manganese-limited conditions, and an A. tumefaciens mutant with a manganese transport deficiency is attenuated for plant virulence. Iron and manganese limitation independently inhibit biofilm formation by A. tumefaciens, and several candidate genes that could impact biofilm formation were identified in each regulon. The biofilm-inhibitory effects of iron and manganese do not rely on recognized metal-responsive transcriptional regulators, suggesting alternate mechanisms influencing biofilm formation. However, under low-manganese conditions the dcpA operon is upregulated, encoding a system that controls levels of the cyclic di-GMP second messenger. Mutation of this regulatory pathway dampens the effect of manganese limitation. IMPORTANCE: Responses to changes in transition metal levels, such as those of manganese and iron, are important for normal metabolism and growth in bacteria. Our study used global gene expression profiling to understand the response of the plant pathogen Agrobacterium tumefaciens to changes of transition metal availability. Among the properties that are affected by both iron and manganese levels are those required for normal surface attachment and biofilm formation, but the requirement for each of these transition metals is mechanistically independent from the other.