Detection of Biofilm Production and Antibiotic Susceptibility Pattern among Clinically Isolated Staphylococcus aureus.

Aim: The increasing antibiotic resistance and the ability to form biofilms in medical devices have become the leading cause of severe infections associated with Staphylococcus aureus (S. aureus). Since the bacteria living in biofilms can exhibit 10- to 1,000-fold increase in antibiotic resistance and implicate chronic infectious diseases, the detection of S. aureus ability to form biofilms is of great importance for managing, minimizing, and effectively treating infections caused by it. This study aimed to compare the tube and tissue culture methods to detect biofilm production and antibiotic susceptibility in MRSA and MSSA. Materials and Methods: The S. aureus isolates were identified by the examination of the colony morphology, Gram staining, and various biochemical tests. Antimicrobial susceptibility testing of all isolates was performed by the modified Kirby-Bauer disc diffusion method as recommended by CLSI guidelines. MRSA screening was performed phenotypically using a cefoxitin disc (30 µg). Isolates were tested for inducible resistance using the D-test, and two phenotypic methods detected biofilm formation. Results: Among 982 nonrepeated clinical specimens, S. aureus was isolated from 103 (10.48%). Among 103 clinical isolates of S. aureus, 54 (52.42%) isolates were MRSA, and 49 (47.57%) were MSSA. Among 54 MRSA isolates, the inducible MLSB phenotype was observed in 23/54 (42.59%) with a positive D-test. By TCP method, 26 (48.1%) MRSA isolates were strong biofilm producers, whereas, among all MSSA isolates, only 6 (12.2%) were strong biofilm producers. Conclusion: MRSA showed strong biofilm production in comparison with MSSA. The TCP method is a recommended reliable method to detect the biofilm among S. aureus isolates, and the TM method could be useful for the screening of biofilm production in S. aureus in the routine clinical laboratory.

Comparative evaluation of biomechanical changes and aberration profile following accelerated collagen cross-linking using hypo-osmolar and iso-osmolar riboflavin: A prospective study.

PURPOSE: To compare the changes encountered in corneal biomechanics and aberration profile following accelerated corneal collagen cross-linking (CXL) using hypo-osmolar and iso-osmolar riboflavin in corneal thicknesses of <400 and >400 microns, respectively. METHODS: This is a prospective, interventional, comparative study involving 100 eyes of 75 patients with progressive keratoconus. Eyes were divided into two groups based on corneal thickness: group 1 included eyes with a corneal thickness of <400 microns who underwent hypo-osmolar CXL, and group 2 included eyes with a corneal thickness of >400 microns who underwent iso-osmolar CXL. Corneal biomechanical and aberration profiles were evaluated and compared between groups. RESULTS: In group 1, all higher-order aberrations (HOA) except secondary astigmatism significantly decreased from baseline; however, in group 2, only coma and trefoil decreased. The corneal resistance factor and corneal hysteresis significantly improved in both groups, which was significantly greater in group 2 than in group 1. The change in inverse radius, deformation amplitude, and tomographic biomechanical index was significantly improved in group 2 as compared to group 1. CONCLUSION: Improvement in corrected distance visual acuity and decrease in HOA were significantly better in the hypo-osmolar CXL group; however, the improvement in biomechanical strength of the cornea was significantly better in the iso-osmolar group.

Comparison of Clinical Outcomes of Implantation of Foldable Hydrophobic Acrylic Intraocular Lens With and Without Heparin Surface Modification in Indian Diabetic Patients.

Background This study aimed to compare the clinical outcomes of a heparin surface-modified (HSM) hydrophobic acrylic foldable intraocular lens (IOL) (CT LUCIA 601PY) and non-heparin-modified hydrophobic acrylic foldable IOL (AcrySof IQ SN60WF) in diabetic patients undergoing phacoemulsification. Methodology This randomized, single-surgeon, double-masked controlled trial was conducted at Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi. In this randomized controlled trial, 100 eyes of 100 diabetic patients with or without mild-to-moderate diabetic retinopathy were enrolled (HSM IOL, n = 50; non-HSM IOL, n = 50). Outcome measures were aqueous flare, visual acuity, and anterior chamber depth (ACD). These were measured preoperatively as well as one day, one week, one month, three months, six months, and one year postoperatively. Results The HSM IOL group had significantly lower anterior chamber aqueous flare values (photon count/ms) than the non-HSM IOL group on postoperative day one (9.97 ± 5.2 vs. 17.56 ± 11.3, p < 0.001), postoperative week one (11.47 ± 7.78 vs. 17.06 ± 9.4, p = 0.02), and postoperative month three (7.7 ± 4.1 vs. 12.5 ± 5.6, p = 0.004) of phacoemulsification. The corrected distance visual acuity (CDVA) was significantly better in the HSM IOL group on postoperative day one (uncorrected distance visual acuity: p = 0.022; CDVA; p = 0.005), but there was no significant difference at any other follow-ups. ACD was significantly longer in the HSM IOL group at all follow-ups. Conclusions The implantation of HSM IOL resulted in significantly lower inflammatory reactions in the early postoperative period in diabetics.

Clinical applications of aqueous angiography in glaucoma.

Aqueous humor outflow (AHO) pathways are the main site of resistance causing elevated intraocular pressure in glaucoma, especially primary open-angle glaucoma patients. With the recently introduced technique of aqueous angiography (AA); functional, real time assessment of AHO from proximal (trabecuar meshwork) to distal pathways under physiological conditions has been made possible. AHO pathways are segmental, and AA can identify high-flow region (increased angiographic signals) and low flow region (decreased angiographic signals) in an individual. With the introduction of canal-based minimally invasive glaucoma surgeries (MIGS), the assessment of AHO can help guide the placement of stents/incisions during MIGS procedures. This can allow individualized and targeted MIGS procedures in glaucoma patients for better results. Based on the density of AHO pathways visualized on AA, surgeons can decide whether to perform MIGS or conventional glaucoma surgery for improved outcomes for the patient. Immediate intraoperative assessment for functionality of the MIGS procedure performed is possible with AA, allowing for surgical adjustments of MIGS procedure in the same sitting, if needed. This review provides a summary of the studies performed with AA to date, with a special focus on Indian patients. It covers the basics and clinical applications of AA for improving surgical outcomes in glaucoma patients.

Comparative Evaluation of Topographic Parameters Using Three Different Topographers in Keratoconic and Cross-linked Keratoconic Corneas.

PURPOSE: To compare the parameters of three different topographic devices (Pentacam HR, Oculus Optikgeräte GmbH; Sirius, Costruzione Strumenti Oftalmici; and Cassini, i-Optics) in grading the severity of keratoconus in cross-linked and non-cross-linked eyes. METHODS: This was a prospective comparative interventional study done in a tertiary eye care center, wherein 114 eyes of 68 patients with keratoconus were divided into two groups: 62 eyes that were observed and 52 eyes that were cross-linked. All eyes were evaluated on all three topographers at baseline, 3-month follow-up, and 6-month follow-up. RESULTS: The Sirius showed significantly lower values of mean flat keratometry in comparison to the Pentacam HR (limits of agreement [LoA]: 1.75 to 3.51%) and Cassini (LoA: 1.75 to 3.51%). The mean steep keratometry values were higher for the Cassini in comparison to the Pentacam HR (LoA: 4.39 to 7.02%) and Sirius (LoA: 3.51 to 6.14%). The mean steep keratometry values of the Sirius were significantly lower than those of the Pentacam HR and in both the cross-linked and observation groups (LoA: 3.51 to 6.14%). The mean keratometry values were significantly higher in the Cassini compared to the Pentacam HR (LoA: 3.51 to 8.77%) and significantly lower in the Sirius in comparison to the Pentacam HR (LoA: 3.51 to 6.14%). The mean difference in astigmatism was also statistically significant between the three tomographers in both groups, with the Cassini showing higher values (LoA: 3.51 to 5.26%) and the Sirius lower values than the Pentacam HR (LoA: 5.26 to 6.14%). CONCLUSIONS: The authors conclude the three devices cannot be used interchangeably. The Cassini showed better agreement and correlation with the Pentacam HR in the staging of keratoconus, whereas the Sirius tended to underdiagnose and under-stage the disease. [J Refract Surg. 2024;40(4):e260-e269.].

Management of acute corneal hydrops - Current perspectives.

Acute corneal hydrops (ACH) is a rare but sight-threatening complication of corneal ectasias. We aim to review the current literature on etiopathogenesis, histology, role of ancillary investigations, management, and outcomes of ACH by classifying the various management strategies based on their site of action and the underlying mechanism. A review of the literature was conducted by searching the following databases: PubMed (United States National Library of Medicine), Embase (Reed Elsevier Properties SA), Web of Science (Thomson Reuters), and Scopus (Elsevier BV) till April 2023. The literature search used various combinations of the following keywords: acute corneal hydrops, keratoconus, ectasia, management, keratoplasty. Nine hundred eighty-three articles were identified based on the above searches. Case reports which did not add any new modality of treatment to the existing literature, articles unrelated to management, those with no full text available, and foreign-language articles with no translation available were excluded. Eventually, 75 relevant articles that pertained to the management of ACH were shortlisted and reviewed. Recent studies have described newer surgical interventions like full-thickness or pre-Descemetic sutures, thermokeratoplasty, and plasma injection that aim to close the posterior stromal break. Posterior lamellar keratoplasties act by replacing the posterior torn Descemet's membrane (DM), and early deep anterior lamellar keratoplasty (DALK) has been attempted to combine the correction of the anatomical defect and visual rehabilitation in a single surgery. These surgical interventions may help by reducing the scarring and increasing the number of patients who can be visually rehabilitated with contact lenses rather than keratoplasty.

Changes in confocal microscopy in glaucoma patients after intraocular pressure reduction with medical therapy.

PURPOSE: Topical glaucoma medication is the first line of management to reduce intraocular pressure (IOP) in patients with glaucoma. In this study, we intended to compare the ultrastructural findings of the cornea in patients with glaucoma before and after the reduction of the IOP through confocal microscopy. METHODS: Ten patients (19 eyes) with newly diagnosed glaucoma were recruited from the glaucoma services of our tertiary care center. Demographic parameters were noted, and basic ocular examination, specular microscopy (Topcon SP3000P, Tokyo, Japan), and ultrasonic pachymetry (300 AP, Sonomed Escalon, Stoneham, MA, USA) were performed. In vivo confocal microscopy of corneal sections was performed using the z-ring Confoscan 4.0 (Nidek, Inc., Freemont, CA) at baseline and after 3 months of starting glaucoma medications. RESULTS: The mean age of the patients was 53.53 ± 9.34 years. There was a statistically significant reduction (P < 0.0001) of IOP from 30.21 ± 7.42 mmHg (baseline) to 16.42 ± 4.14 mmHg (3 months). The mean central corneal thickness at baseline was 533.42 ± 3.96 µm, and it further decreased to 521.94 ± 42.45 µm at the end of 3 months (P = 0.006). No significant change was noted in the mean epithelial cell density, mean keratocyte density in anterior and posterior stroma, and the mean endothelial cell density and cell area (P >0.5). There was no significant percentage change in these parameters before and after the lowering of the IOP. CONCLUSION: A short-term (3 months) decrease in IOP using topical glaucoma medications caused a significant reduction in corneal thickness but did not have any significant ultrastructural changes in cornea measured using confocal microscopy.

Low-dose atropine 0.01% for the treatment of childhood myopia: a pan-India multicentric retrospective study.

OBJECTIVE: The objective of this study was to assess the efficacy of low-dose atropine 0.01% in controlling myopia progression among Indian children over a 2-year period. METHODS: This retrospective study, conducted across 20 centres in India, monitored the progression of myopia over 2 years after initiating treatment with 0.01% atropine eye drops. This included children between 6 and 14 years with baseline myopia ranging from -0.5 D to -6 D, astigmatism≤-1.5 D, anisometropia ≤ -1 D and documented myopia progression of ≥0.5 D in the year prior to starting atropine. Subjects with any other ocular pathologies were excluded. RESULTS: A total of 732 children were included in the data analysis. The mean age of the subjects was 9.3±2.7 years. The mean myopia progression at baseline (1 year before starting atropine) was -0.75±0.31 D. The rate of myopia progression was higher in younger subjects and those with higher baseline myopic error. After initiating atropine, myopia progression significantly decreased to -0.27±0.14 D at the end of the first year and -0.24±0.15 D at the end of the second year (p<0.001). Younger children (p<0.001) and higher baseline myopia (p<0.001) was associated with greater myopia progression and poor treatment response (p<0.001 for both). CONCLUSION: Low-dose atropine (0.01%) effectively reduces myopia progression over 2 years in Indian children.

Evaluation of a new device to treat negative dysphotopsia.

PURPOSE: To evaluate the efficacy and safety of Negative Dysphotopsia (ND) Ring implantation for treating and preventing ND. SETTING: Multicentric tertiary eye hospitals. DESIGN: Prospective interventional cohort study. METHODS: 22 patients with ND were enrolled. Eyes with other ocular structural pathologies (corneal, macular, optic nerve head, retinal, neuro-ophthalmological) were excluded. In 15 eyes, the ring was implanted to treat ND (therapeutic group), and in 7 eyes, it was implanted during cataract surgery of the fellow eye as a prophylactic measure (prophylactic group) to prevent the occurrence of ND. Preoperative evaluation included video recording of the patients' complaints aside complete eye examination. Postoperatively, patients were interviewed to confirm resolution of complaints related to ND. The intraoperative difficulties and postoperative adverse events were recorded. A minimum follow-up of 1 year was completed for all eyes. RESULTS: In the therapeutic group, 14 of 15 eyes (93.3%) patients reported complete resolution of ND on the first postoperative day while 1 patient reported persistence of a smaller and lighter temporal shadow. No ND was reported by any patient in any of the 7 eyes treated prophylactically. No significant adverse intraoperative event was recorded; however, vitreous upthrust was noted in 2 of 22 eyes (9.0%). No permanent drop in visual acuity was recorded in the therapeutic group. CONCLUSIONS: ND Ring implantation was an easy, safe, and effective approach for both treating and preventing ND.

Toxic anterior segment syndrome (TASS): A review and update.

Toxic anterior segment syndrome (TASS) is an acute, sterile, postoperative inflammatory reaction of the anterior segment without vitreous involvement, following an uncomplicated and uneventful ocular surgery, having broad and multiple etiologies. The symptoms of decreased visual acuity and ocular discomfort generally occur within the first 12-48 h after intraocular surgery. The clinical signs include prominent limbus-to-limbus corneal edema, anterior chamber cells, aqueous flare, fibrinous inflammation, and/or keratic precipitates. There can be sight-threatening complications of TASS, such as permanent corneal decompensation, intractable glaucoma, and cystoid macular edema. The causes of TASS are emerging and being reported, so are the newer treatment options for managing the inflammation and its complications. Prevention guidelines for TASS are being updated, and a traceability system for surgical instruments and intraocular fluids used during the surgery is being perpetually developed. It is important to recognize TASS and start treatment on an immediate effect. Hereby, we review the literature on TASS, emphasizing its etiology, pathophysiology, management, prognosis, complications, and the importance of prevention as well as prompt recognition.

Retinol palmitate in management of chronic Steven-Johnson Syndrome with ocular surface keratinization.

PURPOSE: To study the outcomes of topical Retinol Palmitate ophthalmic solution in chronic Stevens-Johnson Syndrome with ocular surface keratinisation. METHODS: It was a comparative interventional study conducted at Rajendra Prasad Centre for Ophthalmic Sciences, Delhi, India from 2020 to 2022 evaluating outcomes of addition of topical Retinol Palmitate to conventional treatment objectively as well as subjectively from baseline up to 12 weeks. RESULTS: A statistically significant improvement was seen in patients who received topical Retinol palmitate at 12 weeks in terms of Schirmer-1 test(p=<0.01), tear prism height on ASOCT(p = 0.02), Rose Bengal staining score of cornea(p = 0.01) and conjunctiva (p < 0.01), reduction of ocular surface keratinisation on impression cytology(p = 0.01) and subjective evaluation using OSDI questionnaire(p = 0.04).Impression cytology revealed goblet cells in Retinol palmitate group at 1 week after initiation of therapy, which increased further at 1 month follow up but reduced at 3 months. No goblet cells were seen in control group at any follow-up. No significant difference was noted between the two groups in terms of visual acuity, tear film breakup time, inflammatory cells on impression cytology and inflammatory markers in tears. CONCLUSION: Topical Retinol palmitate is a safe and effective drug in cases of chronic SJS with ocular surface keratinisation. It has the potential to reverse keratinisation of the ocular surface and promote development of goblet cells. However, the survival of goblet cells is not long lasting.

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.

Management and prevention of corneal graft rejection.

The management of an episode of corneal graft rejection (CGR) is primarily by corticosteroids. Immunomodulators are useful for long-term immunosuppression and in dealing with cases of high-risk (HR) corneal grafts. The classical signs of CGR following penetrating keratoplasty (PKP) include rejection line, anterior chamber (AC) reaction, and graft edema. However, these signs may be absent or subtle in cases of endothelial keratoplasty (EK). Prevention of an episode of graft rejection is of utmost importance as it can reduce the need for donor cornea significantly. In our previous article (IJO_2866_22), we had discussed about the immunopathogenesis of CGR. In this review article, we aim to discuss the various clinical aspects and management of CGR.

Antibiotic prophylaxis for cataract surgery - Practice patterns amongst Indian Ophthalmologists.

Purpose: To assess the current trends in use of perioperative antibiotic prophylaxis, especially intracameral antibiotics (ICAB), for cataract surgery in India. Methods: This was an E-survey using a previously validated questionnaire carried out by the All India Ophthalmological Society (AIOS) in August 2022. An E-mail invitation to complete an online 40-point survey was sent to all members of the AIOS using a digital E-mail service (Survey Monkey) and social media platforms. Results: Out of 1804 total respondents, 58% (n = 1022) reported using routine ICAB prophylaxis. Of those using ICAB, 89% (n = 909) reported using it for all cases, whereas the rest used it for specific indications such as post-PC rent (n = 43), one eyed patient (n = 19), and high-risk cases (n = 50). Commercially available moxifloxacin was by far the commonest agent used for ICAB (n = 686, 67%). Eighty respondents (8%) reported noticing occasional toxic reactions and nontoxic corneal edema (n = 64, 6%) with ICAB. Surgeons with >10 years' experience especially practicing in medical colleges used fewer ICAB (OR = 0.52, 95%CI = 0.38 - 0.72, P < 0,001) compared to younger surgeons (<5-year experience) in solo clinics. The commonest reason for nonadoption of IC antibiotics was "unconvinced of the need to use it in my setting" (n = 296, 52% of those who answered this question). Conclusion: IC antibiotic prophylaxis for cataract surgery has significantly increased in India from 40% in 2017 to 58% in 2022. Commercially available moxifloxacin was preferred by the majority users. Intraocular inflammation may occur occasionally and needs safer formulations to avoid this.

DMEK surgical training: An instructional guide on various wet-lab methods.

Descemet membrane endothelial keratoplasty (DMEK) is a partial-thickness corneal transplantation procedure that involves selective transplantation of the Descemet membrane and endothelium. DMEK offers significant advantages over other keratoplasty techniques, such as faster visual rehabilitation, better final visual acuity due to minimal optical interface effects, lower risk of allograft rejection, and less long-term dependence on topical steroids. Despite all its advantages, DMEK has been found to be more challenging than other corneal transplantation techniques, and its steep learning curve appears to be an obstacle to its widespread use and adoption by corneal surgeons worldwide. DMEK surgical training laboratories (wet labs) provide a window of opportunity for surgeons to learn, prepare, manipulate, and deliver these grafts in a risk-free environment. Wet labs are a significant learning tool, especially for those institutions that have limited tissue availability in their local centers. We provide a step-by-step guide for preparing DMEK grafts using different techniques on human and nonhuman models with instructional videos. This article should eventually help the trainees and the educators understand the requirements for performing DMEK and conducting a DMEK wet lab and develop their skills and interests from a wide variety of available techniques.

Prevention and management of childhood progressive myopia: National consensus guidelines.

Myopia is a major public health problem worldwide, including India, with the global prevalence of myopia increasing rapidly over decades. The clinical and socioeconomic impact of myopia is also expected to rise with rising prevalence. Therefore, the focus has now been shifted to prevent the incidence and progression of myopia. However, there is lack of any standardized guidelines for myopia management. This document aims to generate a national-level expert consensus statement on the management of childhood myopia in the Indian scenario. The expert panel of pediatric ophthalmologists consisted of 63 members who met in a hybrid meeting. A list of topics deliberating discussion in the meeting was provided to the experts in advance and they were instructed to provide their opinions on the matter during the meet. The panel of experts then gave their views on each of the items presented, deliberated on different aspects of childhood myopia, and reached a consensus regarding the practice patterns in the Indian scenario. In case of opposing views or lack of a clear consensus, we undertook further discussion and evaluated literature to help arrive at a consensus. A written document is prepared based on recommendations explaining definition of myopia, refraction techniques, components and methods of workup, initiation of anti-myopia treatment, type and timing of interventions, follow-up schedule, and indications for revised or combination treatment. This article formulates evidence-based guidelines for progressing myopes and pre-myopes and also establishes uniformity in the management of childhood myopia in the country.

Necrotizing Scleritis: A Review.

Necrotizing scleritis is the most destructive and vision-threatening form of scleritis. Necrotizing scleritis can occur in systemic autoimmune disorders and systemic vasculitis, as well as following microbial infection. Rheumatoid arthritis and granulomatosis with polyangiitis remain the commonest identifiable systemic diseases associated with necrotising scleritis. Pseudomonas species is the most common organism causing infectious necrotizing scleritis, with surgery the most common risk factor. Necrotizing scleritis has the highest rates of complications and is more prone to secondary glaucoma and cataract than other phenotypes of scleritis. The differentiation between non-infectious and infectious necrotizing scleritis is not always easy but is critical in the management of necrotizing scleritis. Non-infectious necrotizing scleritis requires aggressive treatment with combination immunosuppressive therapy. Infectious scleritis is often recalcitrant and difficult to control, requiring long-term antimicrobial therapy and surgical debridement with drainage and patch grafting due to deep-seated infection and the avascularity of the sclera.