Biphenyl-rGO composite room temperature gas sensor for enhanced amine sensing.

Amines, which are classified as volatile organic compounds (VOCs), serve a variety of purposes in the fields of environmental monitoring, food safety, and healthcare diagnosis. The present technique for detecting amine levels involves sophisticated setups and bulky equipment. Here. In this study, a chemoresistive gas sensor is developed that is cost-effective and easy to operate at room temperature (RT). The sensor is designed specifically for the detection of Ammonia, dimethylamine (DMA), trimethylamine (TMA), and total volatile basic nitrogen (TVB-N). Using biphenyl-reduced graphene oxide (B-rGO) composite gas sensors effectively addresses the issues of low sensitivity-selectivity and long-term instability commonly observed in conventional amine sensors. B-rGO sensor produced sensitivity of ∼3500 and selectivity above 30 for TVB-N sensing. The sensor is stable for temperature fluctuations below 50 °C and shows stable sensing response for period of over 3 months. A Chemoresistive B-rGO sensor was developed using an ultrasonic spray deposition system with optimized flow rate of 50 mL/h. Rapid evaporation of solvent using hot plate has resulted in unique morphology for B-rGO film sensors. The highest sensitivity, ∼836, is obtained for 100 ppm of ammonia with ammonia > DMA > TMA as a sensitivity order. B-rGO showed almost seven times higher amine sensitivity than rGO which highlights the importance of biphenyl in the B-rGO composite. Sensor calibration curve has been presented in the study to understand change in the sensitivity of sensor with increasing analyte gas concentration. The calibration curve has an average R-squared value of 0.98.

IMPACT OF FOVEAL STATUS AND TIMING OF SURGERY ON VISUAL OUTCOME IN RHEGMATOGENOUS RETINAL DETACHMENT.

PURPOSE: To investigate the impact of surgical timing on visual acuity outcomes in retinal detachments based on the preoperative foveal status. METHODS: A retrospective multicenter cohort study was conducted. Cases were stratified into fovea-on, fovea-split, and fovea-off groups. Days to surgery was defined as the time between the preoperative examination and surgery. The main outcome measure was the final postoperative visual acuity. RESULTS: 1,675 cases were studied. More than 80% of fovea-on/fovea-split and fovea-off cases had surgery within 1 and 3 days, respectively. The mean final postoperative visual acuity did not differ significantly between the fovea-on and fovea-split groups (Snellen equivalent [SE] 20/33 ± 20/49 and 20/32 ± 20/39, P = 1.000) and did not change significantly based on days to surgery in either group. The mean final postoperative visual acuity was lowest in the fovea-off group (Snellen equivalent = 20/56 ± 20/76, P < 0.001) and was significantly lower in cases where surgery was performed after two or more days when compared with cases performed within 1 day (Snellen equivalent 20/74 ± 20/89 vs. 20/46 ± 20/63, P < 0.001). CONCLUSION: Fovea-on and fovea-split retinal detachments demonstrated comparable visual outcomes. Fovea-off RDs demonstrated worse visual outcomes, which declined further when surgery was delayed by two or more days.

Management of traumatic displacement of LASIK flap.

Background: Although flap-based laser refractive surgeries are being extensively performed worldwide, complications due to the flap may occur years after the procedure leading to severe vision-threatening complications. Purpose: To describe the management of a case of traumatic displacement of a LASIK flap performed 8 years earlier. Synopsis: A 42-year-old male presented to us with complaints of decreased vision in his left eye following trauma with a toy gun sustained a day earlier. His best-corrected visual acuity was Counting fingers @ 2 m, and a slit-lamp evaluation revealed a LASIK flap with its temporal edge folded inwards. Flap repositioning was planned. The final surgical plan was interface irrigation with mechanical debridement, alcohol epitheliectomy, fibrin glue application, and bandage contact lens. His uncorrected visual acuity improved to 6/6, N6 at 5 weeks postoperatively, which was maintained at 8 months postoperatively along with a clear interface. Highlights: Traumatic displacement of LASIK flap years after the procedure is a known complication. However, simple flap repositioning may lead to various complications like epithelial ingrowth, DLK, astigmatism, etc., This video describes how to achieve anatomical and visual rehabilitation in such eyes without any long-term complications. Video link: https://youtu.be/QtWG9hEMsXM.

Recovery course of persistent posterior subretinal fluid after successful repair of rhegmatogenous retinal detachment.

PURPOSE: To investigate best corrected visual acuity (BCVA), subretinal fluid (SRF) absorption time or ellipsoid zone (EZ) restoration time and various variables in patients with persistent SRF after successful primary repair of rhegmatogenous retinal detachment (RRD). METHODS: This retrospective multicenter study allowed independent analysis of the healing pattern by two observers based on composite of serial cross-sectional macular optical coherence tomography (OCT) scans. Univariate and multivariate analyses were implemented. RESULTS: One hundred and three cases had persistent SRF after pars plana vitrectomy, scleral buckling, or pneumatic retinopexy. By univariate analysis, SRF resolution time correlated positively with the number of retinal breaks (p < 0.001) and with increased myopia (p = 0.011). Using multivariate analysis, final BCVA (log MAR) correlated positively with age, duration of RRD, initial BCVA (OR = 3.28; [95%CI = 1.44-7.47]; p = 0.015), and SRF resolution time (OR = 0.46 [95%CI 0.21-1.05]; p = 0.049). EZ restoration time was longer with increasing number of retinal tears (OR = 0.67; [95%CI 0.29-1.52]; p = 0.030), worse final BCVA, and presence of macula-off RRD (OR = 0.26; [95%CI 0.08-0.88]; p = 0.056). SRF resolution time correlated marginally with prone position. CONCLUSIONS: Residual posterior SRF is more common in eyes with multiple breaks or in myopic eyes. Final BCVA is better in younger subjects and in eyes with shorter duration of RRD. Persistent SRF is a self-limited disorder with a mean resolution of 11.2 months with good visual prognosis improving from a mean baseline logMAR of 1.08 to 0.25 at one year.

Reducing the bioburden on organic sanitary napkins and attempt to solve the sterility issue.

Sanitary napkins are technical textile products that women use to hygienically collect menstrual fluids when they are menstruating. Because sanitary napkins must simultaneously fulfil a number of end-use requirements, they have layered constructions. Through the Unnat Bharat Abhiyan, Surat, India, this study explores the eco-friendly (organic material) sanitary napkin production facility in the village of Bhatlai in the Gujarat province of India and identifies an issue. With eco-friendly organic sanitary products, bioburdens are a big problem. The Unnat Bharat Abhiyan accepts recommendations and improvements relating to sterility in a sanitary manufacturing unit after bioburden testing is conducted using various approaches outlined by Sanitary Napkins - Specification (IS 5405:2019). This study seeks to develop sanitary napkins that are sterilized and have no bioburden to replace SAPs (super absorbent polymer) with an ecologically friendly biopolymer that provides competent performance and characteristics to rural women of India living near or below poverty line.

Role of physician extenders: more regulation is necessary before full integration into practice.

PURPOSE OF REVIEW: To discuss the drawbacks and propose recommendations for integrating physician extenders in ophthalmologic practice. RECENT FINDINGS: In this article, the role of utilizing physician extenders in ophthalmology is discussed. A role for physician extenders has been suggested as more and more patients will require ophthalmologic care. SUMMARY: Guidance is needed on how to best integrate physician extenders into eye care. However, quality of care is of the highest importance, and unless there is reliable and consistent training of extenders, using physician extenders to administer invasive procedures (e.g., intravitreal injection) should be avoided due to safety concerns.

Timing of Delayed Retinal Pathology in Patients Presenting with Acute Posterior Vitreous Detachment in the IRIS® Registry (Intelligent Research in Sight).

OBJECTIVE: To determine the timing of delayed retinal pathology in eyes presenting with acute posterior vitreous detachment (PVD). DESIGN: Retrospective database study. SUBJECTS: Patients in the Intelligent Research in Sight (IRIS) registry found to have acute PVD based on the International Classification of Diseases, Ninth and Tenth Revision, codes were followed. METHODS: Patients coded to have a PVD from 2013 to 2018 along with common procedural technology coding of extended ophthalmoscopy were included. Ocular baseline characteristics included visual acuity, lens status, presence or absence of vitreous hemorrhage, myopia, lattice degeneration, and subspecialty training of the treating physician. MAIN OUTCOME MEASURES: Timing (days) to delayed retinal break or detachment RESULTS: A total of 434 046 eyes met inclusion/exclusion criteria, and 10 518 eyes (2.42%) presented with a delayed retinal break or detachment after initial PVD. The median time to retinal break and detachment after initial PVD was 42 (range, 1-365) days and 51 (range, 1-365) days, respectively. Eyes with vitreous hemorrhage (hazard ratio [HR], 9.30; 95% confidence interval [CI], 8.50-10.2), history of retinal break/retinal detachment in the fellow eye (HR, 3.91; 95% CI, 3.64-4.20), lattice degeneration (HR, 2.61; 95% CI, 2.35-2.90), and myopia (HR, 1.42; 95% CI, 1.33-1.53) were found to be at a higher risk of developing delayed break or detachment. CONCLUSIONS: Follow-up examination after initial PVD is necessary to diagnose delayed or missed retinal pathology. In eyes with no initial pathology, providers should consider repeat examination at least once within 6 weeks, and sooner for eyes with higher-risk features. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

Oral mucous membrane grafting for unilateral lid margin keratinization following radiotherapy.

We describe the outcomes of oral mucous membrane grafting as a surgical technique for unilateral lid margin keratinization following radiotherapy. A 47-year- old woman presented with an 8-month history of a white spot in her right eye. She had a history of adenoid cystic carcinoma of the right spheno-ethmoid sinus, for which she underwent radiotherapy. Slit-lamp evaluation revealed lid margin keratinization of the right upper and lower eyelids and a keratin plaque on the corneal surface. We performed excision of the keratin plaque and lid margin keratinization, followed by oral mucous membrane grafting of the upper and lower eyelid margins. Histopathological evaluation of the excised lid margin revealed keratinized stratified squamous epithelium, consistent with lid margin keratinization. The corneal surface and lid margins showed no recurrent keratin deposition at the final follow-up, 11 months postoperatively.

Corneal scarring following collagen cross-linking: evidence of increased lysyl oxidase activity.

PURPOSE: To report a case of corneal scarring following collagen cross linking in a young female. METHODS: A 24-year-old female presented to us with complaints of decreased vision and a white spot in her left eye following collagen cross linking (CXL) performed elsewhere, four years prior. We diagnosed her as a case of left eye leucomatous corneal opacity for which she underwent optical penetrating keratoplasty under local anaesthesia. The excised corneal tissue was evaluated by routine histopathology and immunohistochemistry. RESULTS: At the final follow up visit, one year following corneal transplantation, her visual acuity improved to 20/20, J1 with a clear graft. CONCLUSION: Vision threatening corneal scarring may be rarely noted following CXL.

Macular Findings of Patients on Pentosan Polysulfate Sodium.

INTRODUCTION: In 2018, a unique maculopathy associated with chronic pentosan polysulfate sodium (PPS) use for the treatment of interstitial cystitis (IC) was described, where the authors detailed macular retinal pigment epithelial abnormalities in six patients. In this paper, a retrospective study of a larger patient pool at one large tertiary retina practice was undertaken to evaluate patients taking PPS and their macular findings. MATERIALS AND METHODS: A retrospective chart review was performed on all patients presenting to a single large retina practice between 2011 and 2019. Patient's macular diagnosis, findings, optical coherence tomography scans, and macular auto-fluorescent scans were assessed. This project was Institutional Review Board (IRB) approved by the St Luke's Hospital IRB board (St Louis, MO, USA). RESULTS: Fifty-five patients were identified as taking PPS for IC. Fifty-three patients were found to have a diagnosis consistent with changes attributable to known macular diseases to include macular degeneration and pattern dystrophies. Two (4%) of fifty-five patients had macular findings suggestive of PPS toxicity. The first was a 58-year-old female with subtle retinal pigment epithelium (RPE) deposits on optical coherence tomography that exhibited hyper-autofluorescence. The second was a 72-year-old female with 14 years of PPS use who exhibited RPE excrescences and parafoveal areas of atrophy. CONCLUSIONS: Pentosan polysulfate sodium may be the cause of macular findings in a small percentage of patients referred to a tertiary retina practice. Although causation of macular changes with PPS use has yet to be elucidated, clinicians should be aware of this possibility when assessing patients with atypical macular findings. Future longitudinal studies are necessary to evaluate a definitive relationship. This paper should remind all clinicians of the importance of a throughout review of the patient's medication list as novel toxicities may become apparent years after initial FDA trials. The strength of this study is the larger patient population compared to earlier studies, and the main weaknesses include the retrospective nature of the study, lack of family and genetic testing, and lack of multimodal imaging for all patients.

Incidence of vitreous loss and visual outcome following cataract surgery by surgeons with various levels of experience at a tertiary eye care center in North India.

Purpose: To determine the incidence of vitreous loss and visual outcome after a vitreous loss during cataract surgery performed by surgeons with various levels of experience in adults >40 years of age at a tertiary eye care center in North India. Methods: The study was conducted at a tertiary eye care center in North India. This was an observational, retrospective, cross-sectional study of patients who underwent cataract surgery from August 1, 2011 to July 31, 2014. All adult cataract cases who were operated on from August 1, 2011 to July 31, 2014 and who experienced vitreous loss during their surgery were included in the study. The visual outcomes of these patients who experienced vitreous loss during cataract surgery in uncomplicated cataract and were managed using standard automated vitrectomy techniques were assessed for different cataract surgical techniques (extracapsular, small-incision, and phacoemulsification) as well as at different levels of skill of the operative surgeon (consultant, short term fellow, and long-term fellow). Details of the postoperative period and best-corrected visual acuity (BCVA) were collected from patient records by the principal investigator on day 1, 1 week, 4 weeks, 6 weeks, and 3 months post cataract surgery. Results: Vitreous loss occurred in 374 out of 18,430 patients who underwent cataract surgery from August 1, 2011 to July 31, 2014. The overall incidence of vitreous loss in our study was found to be 2.03% with consultants having a rate of 1.66%, short-term fellows at 5.19%, and long-term fellows at 2.02%. Two hundred eighty-eight patients of the 374 cases followed up for 3 months at the hospital and 75.69% of these patients had a final visual acuity of ≥6/18. Conclusion: In an institute with a structured training program for residents/trainees, the vitreous loss rate is low during cataract surgery. Early intervention and proper management with the standard microsurgical technique by experienced hands can improve the final visual outcome in eyes with vitreous loss. Cystoid macular edema and corneal edema were the most common causes of poor postoperative vision.

Role of AS-OCT in Managing Corneal Disorders.

Optical coherence tomography (OCT) is analogous to ultrasound biometry in the cross sectional imaging of ocular tissues. Development of current devices with deeper penetration and higher resolution has made it popular tool in clinics for visualization of anterior segment structures. In this review, the authors discussed the application of AS-OCT for diagnosis and management of various corneal and ocular surface disorders. Further, recent developments in the application of the device for pediatric corneal disorders and extending the application of OCT angiography for anterior segment are introduced.

Amniotic Membrane Grafting for Ocular Surface Inflammation Following Topical Interferon Alpha 2b Therapy.

We describe a rare case of a 58-year-old female with ocular surface squamous neoplasia (OSSN) in her left eye. She was treated for 12 months with topical interferon alpha-2b (IFNα-2b) eye drops and OSSN resolved completely. She presented with a whitish elevated lesion involving the cornea, limbus, and conjunctival surface after discontinuation of topical IFNα-2b. Excision biopsy along with amniotic membrane grafting was done to stabilize the ocular surface. Histopathological evaluation of the excised tissue revealed ocular surface inflammation with no evidence of malignancy.

Vitrectomy versus Combined Vitrectomy and Scleral Buckle for Repair of Primary Rhegmatogenous Retinal Detachment with Vitreous Hemorrhage.

PURPOSE: To compare pars plana vitrectomy (PPV) with combined PPV and scleral buckle (PPV/SB) for repair of primary rhegmatogenous retinal detachment (RRD) with associated vitreous hemorrhage (VH). DESIGN: Retrospective, observational study. PARTICIPANTS: Patients with RRD and associated VH who underwent PPV or PPV/SB from January 1, 2010, through August 31, 2020, were analyzed. METHOD: We performed a single-institution, retrospective, observational study of 224 eyes with RRD and VH at the time of detachment. We excluded eyes with <6 months of follow-up, a prior history of retinal detachment (RD) repair with vitrectomy or SB, VH that resolved before surgical intervention, and tractional or combined tractional and rhegmatogenous detachments. MAIN OUTCOME MEASURES: Single-surgery anatomic success (SSAS) at 6 months, defined as no recurrent RD requiring surgical intervention. RESULTS: Pars plana vitrectomy and PPV/SB were performed on 138 eyes (62%) and 85 eyes (38%), respectively. The mean age of the PPV and PPV/SB patients was 61.9 and 60.2 years, respectively. Single-surgery anatomic success was achieved in 107 of 138 eyes (77.5%) that underwent PPV and 78 of 85 eyes (91.7%) that underwent PPV/SB. The difference in SSAS between types of treatment was significant (P = 0.006). Mean visual acuity improvement in the PPV/SB group was 0.54 logMAR units greater than that in the PPV group (P = 0.126). The incidence of postoperative proliferative vitreoretinopathy in the PPV/SB group (11.7%) was lower than that in the PPV group (19.5%; P = 0.128). The rate of repeat PPV for non-RD reasons was similar for both the groups (P = 0.437). Final reattachment status was achieved in 137 of the 138 and 84 of the 85 eyes in the PPV and PPV/SB groups, respectively. Final visual acuity improvement was significantly better in eyes with PPV/SB than in eyes with PPV alone (logMAR 2.12 vs. 1.26, respectively; P = 0.011). CONCLUSIONS: In patients with RRD and VH, SSAS was superior in patients treated with PPV/SB compared with those treated with PPV alone. Although not significantly different, the PPV/SB group had better visual outcomes and a lower postoperative proliferative vitreoretinopathy rate.

Purtscher-Like Retinopathy in a Patient with COVID-19.

The emerging literature on the novel coronavirus pandemic has reported several cases of varied retinal findings in patients with COVID-19. We report the case of a 59-year-old male who presented with complaint of bilateral blurry vision following hospital discharge after prolonged hospitalization for severe COVID-19 illness. On ocular exam, the patient demonstrated bilateral cotton wool spots localized to the posterior pole of each eye. Multimodal imaging demonstrated findings consistent with retinal nerve fiber layer infarcts in the areas of the cotton wool spots. Exam and imaging of our patient were most consistent with a Purtscher-like retinopathy. We suggest that as ophthalmologists care for increasing numbers of patients recuperating from COVID-19, they monitor for microangiopathic changes similar to those in our patient.

Workup following retinal artery occlusion-experience from an outpatient retina clinic and the delay in workup.

PURPOSE: Acute retinal artery occlusion (RAO) is an urgent ophthalmic condition often indicative of future ischemic pathology. Patients diagnosed at an outpatient retina clinic must present to an emergency department (ED) or primary care clinic to obtain a systemic workup. We review the overall compliance and suspected delay in completing the required testing. DESIGN: Retrospective cohort study METHODS: Patients presenting with a symptomatic RAO from June 2009 to January 2019 at a vitreoretinal practice (The Retina Institute, St. Louis, MO) were included. Documentation of carotid vasculature and echocardiographic imaging was requested from the patient's primary care physician (PCP), cardiologist, or neurologist. Time to workup (TTW) from RAO diagnosis to receiving appropriate workup and site of workup (ED vs. outpatient setting) were recorded. RESULTS: One hundred forty-seven patients were included. A total of 132 (89.8%) patients were documented as having completed at least one type of cardiovascular or carotid imaging. Seventy-seven patients (52.3%) were documented to have completed both carotid and echocardiographic imaging. Following RAO diagnosis, 97 (66.0%) patients were referred to an outpatient facility while 35 (23.8%) were evaluated at an ED. Mean TTW through an ED setting vs. outpatient was 2.20 days (1.10 STDM, range 0-29) vs.13.6 days (2.23 STDM, range 0-149) respectively (p=0.003). CONCLUSION: Our study gives objective data to the delay suspected in referring patients with acute symptomatic RAO for outpatient workup. We recommend all outpatient ophthalmology and retina practices establish a relationship with a comprehensive or primary stroke center to facilitate urgent testing through an emergency department.