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Byline: Kshitiz. Kumar, Tushar. Sinha, Debashish. Bhattacharya A 26-year-old male had BCVA of plano 20/20 in the right eye (RE) and -2.75 Dsph/-2.0 Dcyl × 20° 20/20 in the left [...]

Byline: Kshitiz. Kumar, Tushar. Sinha, Debashish. Bhattacharya A 69-year-old female presented with right eye vision of 20/120 Snellens. Ultrawide-field fundus imaging showed old vitreous hemorrhage with superotemporal sclerosed vessels post [...]

Introduction: The incidence of post vitrectomy endophthalmitis (PVE) is reported to be between 0.02 and 0.84%. Resterilization of single use instruments is a common practice amidst developing countries to make it more affordable to the patients by reducing the cost of the surgery and also reduce the environmental hazard. The aim of our study is to evaluate the incidence of PVE amidst existing sterilization practices of reused instruments in multiple vitreoretinal centres in India. Methodology: Centres with an endophthalmitis tracking system were invited to participate in a survey. Twenty-five centres were sent a questionnaire via email. The questionnaire included details about the institution, number of vitrectomies performed in a year, sterilization practices followed pre-operatively, intraoperatively and postoperatively, incidence of endophthalmitis and instrument reuse policies. Results: A total of 29 cases of endophthalmitis were reported out of the 47,612 vitrectomies performed across various centres. The mean incidence of endophthalmitis was 0.06%. There was no difference in the rates of endophthalmitis based on various pre-operative, intraoperative or postoperative prophylactic measures. Nearly 80% of the centres change most of the instruments after every case, while the rest reused. The mean number of times a cutter was being reused until discarded was 4.7. Nearly 76% followed a performance-based protocol, and the remaining 24% had a fixed protocol for the number of times an instrument can be reused before discarding it. Conclusion: PVE rates are not significantly different in India despite the multiuse of single use instruments. The purpose of this paper is not to suggest an alternate protocol but to creating one in the future with these results in mind, to rationalise the use of single use instruments, make VR surgery more affordable and also have a positive impact on the carbon footprint of consumables in surgery.

Byline: Subhendu. Boral, Deepak. Agarwal, Arnab. Das, Tushar. Sinha Purpose: To study the outcomes of submacular blood removal with isolated autologous full-thickness retinal pigment epithelial (RPE)-choroid patch graft transplantation in [...]

Byline: Kshitiz. Kumar, Ananya. Ganguly, Tushar. Sinha, Debashish. Bhattacharya A 64-year-old male with longstanding type-2 diabetes mellitus presented with progressive diminution of vision in both eyes for 2 months. Clinical [...]

Byline: Kshitiz. Kumar, Subhendu. Boral, Deepak. Agarwal, Angshuman. Goswami, Tushar. Sinha, Debashish. Bhattacharya Clinical profiles of three patients are enumerated in [Table 1].{Table 1} Fundus examination of both eyes showed [...]

Byline: Subhendu. Boral, Arnab. Das, Tushar. Sinha Purpose: To calculate AIP and to find correlation between hole closure pattern with AIP in idiopathic full thickness macular hole (FTMH) cases. Methods: [...]

The Coastal Bend (CB), Lower Rio Grande Valley (LRGV), and Wintergarden (WG) subregions of south Texas co‐exist in similar socio‐economic contexts but rely on markedly different water sources (CB: precipitation; LRGV: surface water; WG: groundwater). This has led to unique agricultural practices and municipal policies and reinforced mental models adapted specifically to each subregion, both of which are critical to understanding structural causes behind current water use and future water sustainability. To better stakeholder mental models in each subregion, semi‐structured interviews were conducted with individuals with a significant stake in water resource use and management. Results indicated near unanimous consensus among farmers and other stakeholders that water supply is limited and will be increasingly stressed under continued urban population growth. Farmers expressed concern that it will become more difficult to continue farming if additional water resources are not available, while each subregion expressed their own unique concerns: growing bureaucratic oversight and growing population problems (CB), lack of inflows, poor water quality, and international disputes with Mexico (LRGV), and political subdivision, declining groundwater levels, and information technology costs (WG). Mental models were synthesized based on dominant themes expressed by respondents; we synthesized these into two systems thinking archetypes: Tragedy of the Commons and Success to the Successful. Though it is unreasonable to create blanket region‐wide policies, the adoption of under‐utilized conservation practices coupled to stakeholder outreach remains unexplored leverage points, given most stakeholders are unaware of the feedback processes continuing to threaten south Texas water resources.

Background/Aim: To compare the intra-operative video overlay guided enlargement of Area of ILM peeled (AIP) more than three Disc Diameter (DD) versus the inverted flap technique in large (>400 µm ) Full Thickness Macular Holes (FTMH).Methods: Retrospectively, 127 cases of large FTMHs divided into two groups (i) Group A (n= 62)—intra-operative video-overlay guided enlargement of AIP > 3DD performed and (ii) Group B (n= 65)—Inverted flap technique was done. Mean Best Corrected Visual Acuity (BCVA), hole closure rate and postoperative foveal anatomy were noted on Optical Coherence Tomography (OCT).Results: Mean Minimal Diameter of Macular Hole (MDMH) were 632.05 ± 146.62 µm (A) and 677.24 ± 152.08 µm (B). Hole closure rate were 93.55% (A) and 96.92% (B). Mean preoperative BCVA was 1.07 ± 0.37 Log MAR (A) and 0.94 ± 0.23 Log MAR (B). Mean postoperative BCVA at 3 months were 0.73 ± 0.22 Log MAR (A) and 0.83 ± 0.24 Log MAR (B). One-way ANOVA test showed statistically better visual improvement in Group A at 3 months (p= 0.02), 6 months (p= 0.045), 12 months (p= 0.002), and 24 months (p= 0.011). Chi square test revealed Type I pattern of hole closure was statistically more in Group B (p< 0.001). Delayed Recovery of Outer Retinal Layers was more in group B (Pearson Chi square test, p= 0.039).Conclusion: Anatomically, macular hole closure rate as well as closure pattern was better in Group B. But functional improvement was better in Group A.

Byline: Samar. Basak, Tushar. Sinha, Debasish. Bhattacharya, Tushar. Hazra, Sunil. Parikh Intraocular infestation by live Gnathostoma spinigerum is a rare occurrence in humans. Most of the published reports are from [...]

Byline: Samar. Basak, Tushar. Hazra, Debasish. Bhattacharya, Tushar. Sinha Pellucid marginal degeneration (PMD) is a rare and usually a bilateral condition. We report a case of typical PMD with a [...]

Antiperiodic oscillations are particular of systems having antisymmetric eigenvector fields defined by: f ( x → ) = - f ( - x → ) . It is known that the Chua’s circuit also possesses the antisymmetric fields. Therefore, in this paper, we investigate the possibility of observing antiperiodic oscillations in independent and coupled Chua’s oscillators. Chua’s circuits have been coupled using the conjugate variables to find antiperiodic oscillations. Two different coupling schemes are being proposed. In the first scheme, the two Chua’s circuits were directly coupled with each other. However, in the other scheme, the two Chua’s circuits were coupled with a common dynamical environment. Both numerical results and their experimental corroboration have been presented. Results for antiperiodic oscillations in the independent Chua’s circuit have been shown in the Appendix. Domains of antiperiodic oscillations with different number of maximas have been observed for different values of the system’s parameters. Moreover, we also observed predictive scaling relations between different domains of antiperiodic oscillations. [ABSTRACT FROM AUTHOR]

Previous studies had indicated that the effects of vasopressin to increase the permeability of collecting ducts to water and to produce a concentrated urine are mediated through adenosine 3', 5'-monophosphate (cyclic AMP). An investigation was performed to determine whether the lack of response to vasopressin in nephrogenic diabetes insipidus could result from an abnormality in the formation of cyclic AMP. The influence of vasopressin was compared in four water-loaded normal subjects, one patient with vasopressin deficiency, and three patients with nephrogenic diabetes insipidus. Serum and urine osmolality, inulin clearance, and cyclic AMP in urine were determined while 5 dextrose and water was infused at a constant rate before, during, and after administration of vasopressin for 1 hr. Vasopressin given intravenously for 1 hr significantly increased the mean rate of excretion of cyclic AMP in urine from a range of from 1.7 to 3.1 nmol/min before treatment to a range of from 4.7 to 8.9 nmol/min after treatment in the normal subjects and the patient with vasopressin deficiency. There were associated mean increases in urine osmolality from a range of from 39 to 119 mOsm/kg to a range of from 568 to 996 mOsm/kg. In contrast, mean cyclic AMP in urine varied from 0.7 to 1.5 nmol/min and mean urine osmolality varied from 47 to 68 mOsm/kg in the patients with nephrogenic diabetes insipidus and did not change after vasopressin. The findings are interpreted to mean that there is a defect in the adenylate cyclase system in nephrogenic diabetes insipidus. It is not known whether there is an abnormality of the receptor, the enzyme, or both or if there is an associated abnormality of the renal tubules to respond to cyclic AMP.

Extract: Previous studies had indicated that the effects of vasopressin to increase the permeability of collecting ducts to water and to produce a concentrated urine are mediated through adenosine 3′, 5′-monophosphate (cyclic AMP). An investigation was performed to determine whether the lack of response to vasopressin in nephrogenic diabetes insipidus could result from an abnormality in the formation of cyclic AMP. The influence of vasopressin was compared in four water-loaded normal subjects, one patient with vasopressin deficiency, and three patients with nephrogenic diabetes insipidus. Serum and urine osmolality, inulin clearance, and cyclic AMP in urine were determined while 5% dextrose and water was infused at a constant rate before, during, and after administration of vasopressin for 1 hr. Vasopressin given intravenously for 1 hr significantly increased the mean rate of excretion of cyclic AMP in urine from a range of from 1.7 to 3.1 nmol/min before treatment to a range of from 4.7 to 8.9 nmol/min after treatment in the normal subjects and the patient with vasopressin deficiency. There were associated mean increases in urine osmolality from a range of from 39 to 119 mOsm/kg to a range of from 568 to 996 mOsm/kg. In contrast, mean cyclic AMP in urine varied from 0.7 to 1.5 nmol/min and mean urine osmolality varied from 47 to 68 mOsm/kg in the patients with nephrogenic diabetes insipidus and did not change after vasopressin. The findings are interpreted to mean that there is a defect in the adenylate cyclase system in nephrogenic diabetes insipidus. It is not known whether there is an abnormality of the receptor, the enzyme, or both or if there is an associated abnormality of the renal tubules to respond to cyclic AMP.Speculation: The results show that patients with nephrogenic diabetes insipidus do not increase levels of cyclic AMP in urine or concentrate their urine in response to vasopressin. It is proposed that there is a defect in the adenylate cyclase system in these patients which accounts for their lack of response to antidiuretic hormone.

Studies are presented in a patient with pseudohypoparathyroidism who showed a partial response to parathyroid extract. Resistance to the extract was observed after its short-term administration for the fourth time. Serum from the patient contained antibodies of the γG globulin class which bound 125I-labelled bovine parathyroid hormone. Prior incubation of parathyroid hormone with the serum prevented the activation in vitroof adenylate cyclase from pork renal cortex. The antibodies were directed primarily toward the C-terminal portion of the molecule. Thus, clinical resistance to parathyroid hormone is attributed to specific antibodies.