Health transition and eye care policy planning for people with diabetic retinopathy in south Asia.

The prevalence of type 2 diabetes (T2D), associated systemic disorders, diabetic retinopathy (DR) and current health policies in south Asian countries were analysed to assess country-specific preparedness to meet the 2030 Sustainable Development Goals. The south Asian countries were classified by human development index, socio-demographic index, multidimensional poverty indices, and eye health resources for epidemiological resource-level analysis. In south Asia, the prevalence of diagnosed and undiagnosed T2D in adults aged 40 years or above, was higher in Pakistan (26.3%) and Afghanistan (71.4%), respectively; India has the highest absolute number of people with DR, and Afghanistan has the highest prevalence of DR (50.6%). In this region, out-of-pocket spending is high (∼77%). This Health Policy is a situational analysis of data available on the prevalence of DR and common eye diseases in people with T2D in south Asia and available resources to suggest tailored health policies to local needs. The common issues in the region are insufficient human resources for eye health, unequal distribution of available workforce, and inadequate infrastructure. Addressing these challenges of individuals with T2D and DR, a 10-point strategy is suggested to improve infrastructure, augment human resources, reduce out-of-pocket spending, employ targeted screening, and encourage public-private partnerships.

Assessment of eye health programme reach by comparison with rapid assessment of avoidable blindness (RAAB) survey data, Talagang, Pakistan.

BACKGROUND: The purpose of this study was to quantify how much of the burden of visual impairment (VI) and unmet need in Talagang, identified by Rapid Assessment of Avoidable Blindness (RAAB) survey data, has been addressed by Community Eye Health (CEH) programme efforts. METHODS: A RAAB survey was carried out in November 2018, with 2,824 participants in Talagang Tehsil, Punjab, Pakistan, aged 50 and over. Census data were used to extrapolate survey data to the population. Alongside this, a CEH programme was launched, consisting of community eye screening, and onward referral to rural health centres, secondary or tertiary ophthalmological services, as required. This health intervention aimed to address the eye care needs surfaced by the initial survey. From 2018 to 2022, 30,383 people aged 50 or over were screened; 14,054 needed referral to further steps of the treatment pathway and more detailed data collection. Programme data were compared to estimates of population unmet needs. Main outcome measures were prevalence of VI, and proportion of need met by CEH Programme, by cause and level of VI. RESULTS: Among those aged 50 and over, 51.0% had VI in at least one eye. The leading causes were cataract (46.2%) and uncorrected refractive error (URE) (25.0%). In its first four years, the programme reached an estimated 18.3% of the unmet need from cataract, and 21.1% of URE, equally in both men and women. CONCLUSIONS: Robustly collected survey and programme data can improve eye health planning, monitoring and evaluation, address inequities, and quantify the resources required for improving eye health. This study quantifies the time required to reach eye health needs at the community level.

Pressure-dependent band gap engineering with structural, electronic, mechanical, optical, and thermal properties of CsPbBr3: first-principles calculations.

CONTEXT: In the renewable industry, pressure-dependent CsPbBr3 perovskite has a lot of potential due to its exceptional properties. Present work revealed the mechanical stability of CsPbBr3 between 0 to 50 GPa. The bandgap of unstressed CsPbBr3 is 2.90 eV, indicating a direct bandgap. Band gap values decrease by increasing external pressure. CsPbBr3 structure showed a direct band gap from 0 to 35 GPa and in-direct from 40 to 50 GPa. The unit cell volume and lattice constants are substantially decreased. Mechanical parameters, i.e., Young's modulus, bulk modulus, anisotropy factor, shear modulus, and poison's ratio are obtained. Under ambient conditions, the mechanical properties of CsPbBr3 showed ductile behavior and with induced pressure, their ductility has significantly improved. By applying stresses ranging from 0 to 50 GPa, the considerable fluctuation in values of dielectric function (imaginary and real), absorption, reflectivity, loss function, refractive index (imaginary and real), and conductivity (imaginary and real), was also identified. When pressure rises, the optical parameters increase and drag in the direction of high energies. Response functions are used to predict the density of states and the phonon lattice dispersion to study the phonon properties. By using the quasi-harmonic Debye model, the thermal effect on the free energy, entropy, enthalpy, and heat capacity were predicted and compared. These results would be useful for theoretical research and indicate how external pressure significantly affects the physical characteristics of CsPbBr3 perovskites, which may open up new possibilities for use in optoelectronic, photonic, and solar cell applications. METHODS: The structural, electrical, mechanical, optical, and thermal properties of cesium lead bromide (CsPbBr3) are investigated by applying external pressure from 0 to 50 GPa, using generalized gradient approximations (GGA) and Perdew-Burke-Ernzerhof (PBE) with CASTEP code built-in material studio by density functional theory (DFT).

Clinical Presentation of Carotid-Cavernous Fistula and Outcomes of Endovascular Balloon Embolization

Objectives: To describe the clinical presentation of carotico-cavernous fistula (CCF) and outcomes of endovascular balloon embolization in a tertiary care center in a developing country. Materials and Methods: This retrospective interventional case series included 18 patients who underwent endovascular balloon embolization from 2019 to 2022 at Lahore General Hospital in Lahore, Pakistan. The analyzed data consisted of age, gender, cause and type of CCF, clinical presentation, diagnostic technique used, intervention, and the results of two-month follow-up. Patients with incomplete records and coil embolization were excluded. Digital subtraction angiography was done in all cases followed by endo-arterial balloon embolization. Procedures were carried out under general anesthesia via femoral artery approach. A single balloon was sufficient to close the fistula in all cases. Results: There were 18 patients who met the inclusion criteria. Sixteen patients had direct CCF, and the mean age of the patients was 27.2±12.6 years. The commonest cause of CCF was trauma, and the mean time of presentation after trauma was 7.89±7.19 months. The male-to-female ratio was 8:1. Preoperative visual acuity was worse than 6/60 in 8 patients, between 6/60 and 6/18 in 7 patients, and better than 6/18 in 3 patients. The mean intraocular pressure was 16.06±3.37 mmHg preoperatively and 14.83±3.49 mmHg postoperatively (p=0.005). Endovascular embolization was successful in 15 patients (83.3%). One patient developed epidural hematoma as a complication of the procedure, which was drained later. There was no mortality related with the procedure. Conclusion: Balloon embolization via the femoral artery is an efficient technique in direct as well as indirect CCF. It is safe and simple with very good results if performed in a timely manner.

Perceived usefulness of medical teachers towards online learning using technology acceptance model.

Objective: To determine medical teachers' acceptance of and attitude towards online learning, and to gather their recommendations about how it can be incorporated in the educational system. METHODS: The mixed method study was conducted at Gujranwala Medical College, Gujranwala, Pakistan, from August 2021 to January 2022, and comprised medical teachers involved in online teaching during the coronavirus disease-2019 pandemic. Quantitative data was gathered using an online questionnaire based on the technology acceptance model. The qualitative component was explored through 2 focussed group discussions. Data was analysed using SPSS 25. RESULTS: Of the 50 teachers, 31(62%) were males and 19(38%) were females. The overall mean age was 42.9±7.9 years, and the mean teaching experience was 10.9±7.9 years. Mean perceived usefulness score was 3.2±0.9 and the mean perceived ease of use score was 3.6±0.6. The mean scores were 3.3±0.9 for intention to use and 3.5±0.7 for attitude towards computer use. There was a strong positive correlation of perceived usefulness with intention to use and attitude towards computer use (p<0.05), while perceived ease of use and intention to use had a strong correlation with attitude towards computer use (p<0.05). There were total 12 participants in focussed group discussions; 2(16.7%) females and 10(83.3%) males with mean age 44.34±5.23 years. A total of 4 major themes were identified. Conclusion: Majority of medical teachers strongly agreed with the acceptance of e-learning, and agreed with its perceived usefulness and perceived ease of use for online learning.

Investigation of structural, mechanical, electronic and optical responses of Ga doped aluminum arsenide for optoelectronic applications: By first principles.

Owing to the rapidly increasing performance of ternary semiconductors; Aluminium Gallium Arsenide (Al1-xGaxAs; x = 0, 0.25, 0.50, 0.75) has been studied by first-principles calculations in Cambridge Serial Total Energy Package (CASTEP-Code). Density functional theory in the frame of full potential linear augmented plane wave (FP-LAPW) is used. The structural, electronic, and optical behavior of the Zinc Blend (ZB) structure of AlAs with Ga impurity was computed by using generalized gradient approximation (GGA) as exchange potential and Perdew-Burke-Ernzerhof (PBE) as functional. Changes in lattice parameters (a), bulk modulus (66.07-76.85), hardness (5.79-8.91) and machinability (1.36-1.46), band gap energy (Eg), and optical properties are computed and discussed in this work. Lattice parameters and elastic constants showed excellent agreement with the reported data whereas some properties were found to excel much more than the theoretical reports. Remarkable bandgap reduction from 1.7eV to 0.28eV is very encouraging in its low-energy applications in UV and visible ranges. Real (Re) and Imaginary (Img) parts of the dielectric function and refractive index shifts towards lower energy values show good agreement with those of theoretical and experimental works. We contribute to the knowledge and characterization of Al1-xGaxAs facilitating its integration into various technological advancements such as photovoltaic, laser, diodes, and high-frequency transistors.

Comparative investigations of electronic, mechanical and optical responses of Ra-doping in Barium Titanate for optoelectronic applications: A computational insight.

This unique study examined the theoretical pure BaTiO3 and doped Ra (Ba1-xRaxTiO3) impact on electronic, mechanical and optical responses were using Heydscuseria-Ernzerhof screened hybrid functional (HSE06) and generalized gradient approximation (GGA-PBE) with norm-converging pseudopotential approaches in the density functional theory. Computed the lattice constant and bond lengths for pure (BaTiO3) and doped atoms as well as explored the changes of consequences of electronic, mechanical and optical responses. The calculated values indicate the BaTiO3 is an indirect characteristic and an optically inactive nature. The low energy state and also conduction band of the crystal structure to transform to the direction of low energy and narrows the electronic band gap. The bandgap of pure BaTiO3 is continually reduced which shifts the Fermi energy level Eg. When increasing the doping impurities (x) of (Ra) in BaTiO3, the band gap shifts from indirect (X-G) to direct (X-X) nature and become optically active. The elastic and mechanical responses are essential for suitable (Ra) doped material ensuring structural integrity and predicting a ductile behavior. Kleinman coefficient (ξ), it is clear that (Ra)-doped materials shows slightly large resistance to bond bending and bond angle distortion as compare to pure BaTiO3. Optical characteristics of the both pure and doped (Ra) materials in the core level spectra are thoroughly investigated. Optical coefficients are obtained in the energy scale start from 0 to 20 eV. Moreover, the results of optical properties show excellent influence of doping so that this material can be employed as UV filter in the UV region and in optoelectronics devices.

Clinical Patterns And Outcomes Of Retinoblastoma In A Tertiary Care Centre Of A Developing Country.

A retrospective study was conducted for which records of patients with Retinoblastoma (RB), treated at Lahore General Hospital between 2017 and 2021, were retrieved on February 1, 2022. Staging of RB, neuroimaging, RetCam images, and treatment were analysed. The study included 47 patients (22 females and 25 males). Mean age of presentation was 26.5±15 months. Records of 84 eyes (37 bilateral and 10 unilateral) were examined. Family history was positive in only (n=3) 6.3% cases. Mean follow-up was 22.94±14.4 months. Leucocoria was the commonest presentation, seen in 72 (85.7%) eyes, proptosis in 8 (9.5%), huge fungating mass in 2 (2.4%), while tumour was diagnosed because of screening in 2 (2.4%) patients. Posttreatment complications included cataract in two patients, Ischaemic chorioretinal toxicity, transient macular oedema, orbital oedema and transient intra cranial oedema in one patient each. Two patients had metastasis and underwent systemic chemotherapy. The study showed that patients with retinoblastoma can achieve better results if diagnosed early and treated with newer treatment options.

First-principle calculations to investigate structural, electronic, mechanical, optical, and thermodynamic features of promising (La, In)-doped AlSb for optoelectronic applications.

CONTEXT: A remarkable change in lattice parameters and bulk modulus is achieved by the suitable addition of Al (Al1-x Lax Sb) and In (Al1-x Inx Sb) atoms in the AlSb compound. Electronic responses like band structure, the total partial density of states, and the elemental density of states are thoroughly investigated. The computed values indicate that the binary compound AlSb is an indirect band gap and an optically inactive response. After increasing the doping concentrations (0.25, 0.5, 0.75) of La and In in AlSb, the band gap changes from indirect to direct nature. Hence, Al1-0.75 La0.25 Sb, Al1-0.50 La0.50 Sb, Al1-0.75 In0.25Sb, and Al1-0.50 In0.50Sb become optically active. The illustrious roles of Al-3p and In-4d states on the band gap and nonlinear responses of these compounds are extensively explored by the comparison between the computed results of ultra-soft and norm converging pseudopotentials. The excess specific heat (CV), enthalpy of mixing (Hm), and phonon dispersion curves resulting from the concentrations "x" are estimated in order to investigate the thermodynamic stability responses of the pristine and doped AlSb. The obtained CV and thermal coefficient statistics for Al1-x Lax Sb and Al1-x Inx Sb may be useful for a good mapping of experimental results and examining these compounds' enharmonic responses. There is a valuable change in optical characteristics like dielectric functional, absorption, conductivity, and refractive index due to the addition of (La, In) impurities in AlSb. It is further observed that Al1-0.75 La0.25 Sb, Al1-0.50 La0.50 Sb, Al1-0.75 In0.25Sb, and Al1-0.50 In0.50Sb are significantly mechanically stable compared to pristine AlSb. The above results suggest that Al1-x Lax Sb and Al1-x Inx Sb are high-performance optical materials and can be promising potential candidates for optoelectronic applications. METHODS: The structural, electronic, mechanical, vibrational, and optical responses of the pure and doped Al1-0.75 La0.25 Sb, Al1-0.50 La0.50 Sb, Al1-0.75 In0.25Sb, and Al1-0.50 In0.50Sb are investigated, using Heydscuseria-Ernzerhof screened hybrid functional (HSEO6) and generalized gradient approximation (GGA) with norm-converging and ultra-soft pseudopotential techniques in the density functional theory.

A comprehensive correlated analysis of Ra-Doped (ZnO2, ZnO) for optoelectronic applications: a first-principle study.

CONTEXT: Zinc oxide (ZnO) exhibits bulk-like behavior and is modified by radium doping to attain favorable electronic properties. The elastic and mechanical response of ZnO2 is much more favorable than ZnO material. The change in thermal expansion, Debye temperature, free energy, entropy, and specific heat leads it to be a good candidate for thermodynamic applications at low and high temperatures. Optical properties like dielectric function, absorption, refraction, reflection, and refractive index obtained after suitable doping transform the material as optically active. ZnO2 has low reflectivity and zero absorption below the electronic band gap as compared to ZnO in a wider spectral range. Our analyses on doped ZnO2 and ZnO make us confident for a wide range of applications in optoelectronic and anti-bacterial treatment in biomedical devices. Especially due to high flexibility and high light transmission, ZnO2 is an excellent applicant for transparent electrodes. METHODS: Density functional theory has been employed in consistency with generalized gradient approximation (GGA) with PBEsol to analyze the structural, electronic, elastic, mechanical, thermodynamic, and optical response of pure and Ra-doped (ZnO2 and ZnO) materials.

A comparison of SRK/T formula with Hill RBF 2 and Barrett Universal II in the calculation of intraocular lens power.

OBJECTIVE: To compare the accuracy of SRK/T, Barrett Universal II and Hill radial basis activation function-2 formulas in intraocular lens power calculation using different axial lengths. METHODS: The retrospective study was conducted at the Lahore General Hospital, Lahore, Pakistan, and comprised data from June to December 2020 of patients who underwent phacoemulsification with non-toric, monofocal intraocular lens implantation. Data was sorted in 3 groups on the basis of axial length; group 1 22-25mm, group 2>25mm, and group 3 <22mm. Intraocular lens power was calculated using SRK/T with IOL Master, while online calculators were used for Barrett Universal II and Hill radial basis activation function-2 formulas. Data was analysed using SPSS 21. RESULTS: Of the 100 patients, 47(347%) were males and 53(53%) were females. There were 49(49%) diabetics, and 57(57%) were right eyes. There were 77(77%) patients with mean age 62.38±9.5 in group 1, 17(17%) patients with mean age 52.59±12.78 in group 2, and 6(6%) patients with mean age 61.33+7.61 years in group 3. Mean axial length in group 1 was 23.55±0.81mm with anterior chamber depth of 3.1± 0.37mm. In group 2, mean axial length was 27.54±2.8mm, with anterior chamber depth of 3.4±0.15mm. In group 3, mean axial length was 21.74mm, with anterior chamber depth of 3.14±0.44mm. Mean prediction error of SRK/T versus Barrett Universal II was 0.092±0.041D (p=0.078), SRK/T versus Hill radial basis activation function-2 was 0.066±0.037D (p=0.221) and Barrett Universal versus Hill radial basis activation function-2 was -0.025±0.019D (p=0.553). Mean prediction error of group 1 versus group 2 was -0.105±0.14D, group 2 versus group 3 was 0.046±0.216D and group 2 versus group 3 was 0.151±0.243D (p=1.0). In 74% eyes, absolute prediction error was within ±0.5D in group 1, 64% in group 2 and 50% in group 3 for all formulas. CONCLUSIONS: SRK/T formula was found to be as reliable as Barrett Universal II and Hill radial basis activation function-2 in terms of calculating intra ocular lens power for all axial lengths.

Ophthalmology foundation Ophthalmic Surgical Competency Assessment Rubric (OSCAR) for pterygium surgery.

Background: Pterygium surgery is a procedure commonly performed by ophthalmologists. Valid, objective methods are needed to assess competence in this procedure. Methods: A panel of 5 specialists consisting of members from different regions of the world including Pakistan, United States, Iran, Mongolia and Peru was formed to create a rubric for assessment of pterygium surgery by residents. The assessment rubric was developed using the standard template of Ophthalmology Surgical Competency Assessment Rubrics (OSCARs) previously published. The rubric was designed using a modified Dreyfus model of skill acquisition on a four-point behavioral scale. Results: The rubric consisted of 14 essential steps in pterygium surgery and 5 global indices. The content and face validity of the rubric was refined by repeatedly reviewing the rubric on Googledocs and considering critiques by a panel of 10 cornea specialists from around the world. Each step was divided into four levels, from novice to competent. The skill required for each level was described specifically to help decrease rater subjectivity. Conclusions: The OSCAR for pterygium surgery has face-validity and can be used effectively for both teaching and assessing ophthalmology residents in training programs across the world.

Leader emotion regulation, leader-member exchange (LMX), and followers' task performance.

Drawing on Social Exchange theory, we investigated the direct link between leaders' emotion regulation strategies (i.e., surface acting and deep acting) and follower task performance. In addition, we investigated the indirect link between leaders' emotion regulation strategies and follower task performance via leader-member exchange (LMX). Using survey data (N = 301) from the banking industry, we found that leader surface acting only has an indirect negative relationship with follower task performance via LMX, while leader deep acting has both a direct and an indirect positive relationship with follower task performance. The result showed that leader emotion regulation strategies perform a key role in enhancing/damaging LMX and that leaders need to be vigilant regarding their own emotional behaviors. That is, they can develop positive relationships with their followers by employing deep acting but that surface acting damages their relationship with followers. Implications of this study, limitations, and future research are discussed.

Characteristics of acute central serous chorioretinopathy on optical coherence tomography - a retrospective study.

Central Serous Chorioretinopathy is a common chorioretinal disease which is characterized by serous detachment of the neurosensory retina from the Retinal Pigment Epithelium (RPE) in the macular area. The purpose of this study was to find out the characteristics of acute central serous chorioretinopathy on optical coherence tomography. This study was conducted at Lahore General Hospital and Yaqin Vision from January 2016 to June 2018. The retrospective analysis of all optical coherence tomography scans of 50 patients with acute central serous chorioretinopathy was done. Patients having wet macular degeneration producing similar findings were excluded. Each optical coherence tomography scan was carefully studied using the line scan, radial scan and 3-D scan. Central foveal thickness, foveal contour, status of ellipsoid layer, retinal pigment epithelium and Sub-retinal fluid was analyzed by a single observer. Out of total 50 patients, 37 were males and 13 were females. Serous macular detachment was observed in all the patients, pigment epithelial detachment was found in 13 patients, brush border pattern was present in 31 patients, retinal pigment epithelium bulge was found in 36 patients, dipping pattern was identified in 9 patients and intra-retinal hyper-reflective dots was observed in 3 patients. Hence, optical coherence tomography may be helpful in diagnosing the characteristics of central serous chorioretinopathy and understanding the mechanisms of the disease.

Outcome of interventional treatment modalities for retinoblastoma: Experience at a tertiary care centre in Pakistan.

Retinoblastoma is the most common intra-ocular malignancy found in children in their infancy. Originating from the retinal cells, the disease has a significant association with mortality and morbidity. A case series study was conducted at the Lahore General Hospital eye department, from November 2016 to January 2018. Nineteen children having retinoblastoma in 19 eyes were included in the study. The retinoblastoma-affected eyes were classified according to the International Classification of Retinoblastoma (ICRB). Treatments assigned were based on the severity of the disease, monetary allowance and intervention availability. The treatment modalities employed were chemo-reduction, Ophthalmic artery chemosurgery (OAC), Intravitreal Melphalan, Cryotherapy and laser photocoagulation. To measure the outcome, the follow up period was between 6 to 12 months. The primary outcome measures among the majority of the patients were regres sion or obliteration of the tumour. Failure of treatments were also recorded which included progression of the malignancy requiring enucleation. This study concludes that the newer modalities such as OAC and Intravitreal Melphalan have shown promising results for tumour regression, leading to vision salvation, even at higher grades of ICRB.

Amniotic membrane to the rescue of partially necrosed dermis fat graft.

A 25-year-old woman underwent dermis fat graft on the right side for persistent ocular pain with her polymethylmethacrylate (PMMA) spherical orbital implant. One week later she developed dermal necrosis of the dermis fat graft with potentially devastating fat atrophy if left uncovered. Amniotic membrane graft epithelial side up was sutured to the conjunctiva surrounding the fat. 2 weeks later the graft epithelialized with preservation of fat. Role of amniotic membrane graft as a routine lining over dermis fat grafts to promote conjunctival healing and prevent fat exposure needs to be studied in prospective studies.

Unilateral frontalis sling for the surgical correction of unilateral poor-function ptosis.

PURPOSE: To evaluate the functional and cosmetic results after frontalis sling repair for unilateral ptosis associated with either poor levator function or synkinesis. METHODS: Preoperative and postoperative photographs and records of 127 patients who underwent unilateral frontalis sling ptosis repair were retrospectively reviewed. An eyelid crease incision was used in all cases, with suturing of the sling material directly to tarsus. RESULTS: Preoperative diagnosis for all patients was either unilateral poor-function blepharoptosis or ptosis associated with levator synkinesis. Underlying causes included 75 congenital, 13 posttraumatic, 11 congenital "jaw-winking," 10 cranial nerve III palsies, 9 myasthenia gravis, 5 chronic progressive external ophthalmoplegia, and 4 congenital "double-elevator" palsies. There was a mean follow-up of 11.6 months. Twenty-eight eyelids required reoperation: 11 for undercorrection, 6 for overcorrection with keratopathy, 2 for upper eyelid crease revision, 7 for correction of poor contour, 1 for a broken sling, and 1 for removal of an infected exposed polytetraflouroethylene sling. Lagophthalmos of greater than 2 mm was noted in 18 patients, 5 of whom had persistent keratopathy requiring reoperation. No other complications were reported, except for 1 suture granuloma. Good to excellent final postoperative eyelid height was achieved in 121 patients (95%) after all surgeries and with conscious recruitment of the frontalis muscle. A large majority of patients and/or parents expressed satisfaction with the final cosmetic result and were not bothered by any asymmetric lagophthalmos in downgaze or lack of a synchronous blink. However, 19 of 25 amblyopic patients were less satisfied with passive eyelid height as they failed to recruit the ipsilateral frontalis muscle to activate the sling during binocular viewing. In 17 of these 19 patients, good to excellent eyelid height could be achieved with conscious active brow elevation. CONCLUSIONS: Unilateral sling provides good to excellent functional and cosmetic results in unilateral poor-function ptosis. However, patients with amblyopia usually require conscious effort to activate the frontalis muscle to achieve satisfactory eyelid height.