The Evolving Surgical Paradigm of Scleral Allograft Bio-Tissue Use in Ophthalmic Surgery: Techniques and Clinical Indications for Ab-Externo and Ab-Interno Scleral Reinforcement.

To review the latest surgical advances and evolving clinical use of scleral bio-tissue for reinforcement in the eye and review the published literature on novel surgical applications of scleral allograft bio-tissue. Conventional surgical procedures for scleral reinforcement using homologous scleral allograft have been traditionally ab-externo interventions comprising of anterior or posterior reinforcement of the sclera for clinical indications such as trauma, scleromalacia, glaucoma drainage device coverage, scleral perforation, buckle repair as well as posterior reinforcement for pathologic myopia and staphyloma. There have been a few novel ab-interno uses of scleral bio-tissue for reinforcement in both retina and glaucoma. Over the last decade, there has been an increase in peer-reviewed publications on scleral reinforcement, reflecting more interest in its clinical applications. With favorable biological and biomechanical properties, scleral allograft may be an ideal substrate for an array of new applications and surgical uses.

Remote vision testing of central retinal acuity and comparison with clinic-based Snellen acuity testing in patients followed for retinal conditions.

Introduction: The unmet need for remote monitoring of visual function with home-based, patient-centric technologies became increasingly palpable during the COVID-19 pandemic. Many patients with chronic eye conditions lack access to office-based examinations. Here, we evaluate the efficacy of the Accustat® test, a virtual application for measuring near visual acuity on any portable electronic device via telehealth. Materials and methods: Thirty-three adult subjects from the telehealth remote monitoring service of a retina practice performed the Accustat® acuity testing at home. All patients underwent in-office general eye examination with additional fundoscopic examination and optical coherence tomography retina imaging. Best corrected visual acuity assessment using a Snellen chart was compared with remote visual acuity assessment with the Accustat® test. Visual acuity was analyzed and compared between the best-corrected near visual acuity potential achieved on the Accustat® and in-office distance best-corrected Snellen visual acuity. Results: The mean logarithm of the minimum angle of resolution (logMAR) visual acuities of all eyes tested using the Accustat test was 0.19 ± 024 and for the office Snellen test 0.21 ± 0.21. A linear regression model with 95% confidence intervals reveals that there is a strong linear relationship between Accustat logMAR and office Snellen logMAR. Bland-Altman analysis demonstrated 95.2% significant agreement between Accustat and Office Snellen's best corrected visual acuity. Intraclass correlation coefficient (ICC = 0.94) demonstrated a strong positive correlation between at home versus office visual acuity. Conclusion: There was a high correlation between the visual acuity measured with the Accustat near vision digital self-test and the office Snellen acuity test, suggesting the potential utility of scalable remote monitoring of central retinal function via telehealth.

EPIRETINAL MEMBRANE WITH FOVEAL HERNIATION: Visual and Surgical Outcomes.

PURPOSE: Foveal herniation occurs when neuroretinal tissue protrudes through and above the level of an epiretinal membrane. This study describes the visual symptoms and spectral domain optical coherence tomography findings associated with foveal herniation and evaluates the postoperative visual, anatomical, and surgical outcomes. METHODS: A multicenter retrospective review of patients diagnosed with epiretinal membrane identified 59 patients with preoperative foveal herniation on spectral domain optical coherence tomography. Data regarding visual symptoms, preoperative and postoperative best-corrected visual acuity (BCVA), central retinal thickness, macular volume, and size of foveal herniation were collected, and statistical analysis was performed. RESULTS: A total of 58 of the 59 patients with foveal herniation underwent surgical epiretinal membrane peeling, with foveal contour restored in 53.5% of patients after surgery. Average BCVA improved from 20/80 to 20/40 Snellen equivalent at most-recent postoperative visit (P < 0.0001). The average central retinal thickness decreased from 632 µm to 432 µm (P < 0.0001) and the average macular volume decreased from 11.3 mm3 to 9.5 mm3 (P < 0.0001) at 3 months postoperatively. Preoperatively, greater herniation height was associated with worse BCVA (P = 0.008), greater central retinal thickness (P = 0.01), retinoschisis, cystoid macular edema, foveolar detachment, ellipsoid zone abnormality, and external limiting membrane abnormalities (P < 0.05). Postoperatively, there was a decrease in retinoschisis, cystoid macular edema, foveolar detachment, ellipsoid zone, and external limiting membrane abnormality (P < 0.05) on spectral domain optical coherence tomography. CONCLUSION: Patients with larger foveal herniation height had greater preoperative central retinal thickness, worse preoperative and postoperative BCVA, and more intraretinal abnormalities on spectral domain optical coherence tomography. Surgical epiretinal membrane peeling in patients with foveal herniation resulted in a significant improvement in patients' BCVA and microstructural abnormalities.

Remote patient monitoring of central retinal function with MACUSTAT®: A multi-modal macular function scan.

Introduction: There is significant unmet need for patient-centric remote monitoring of visual function for chronic retinal diseases, as demonstrated by the COVID-19 pandemic. The Macustat® central retinal function scan is a novel cloud-based digital health application for remote monitoring. The aim of this study is to assess the efficacy of the Macustat® compared to traditional in-office retinal evaluations. Materials and methods: Patients with underlying macular pathology underwent office-based retinal and visual acuity examinations and OCT macula imaging followed by remote tele-monitoring assessment with the Macustat. Central visual function was assessed with the multi-modal Macustat test using dynamic virtual Amsler grid testing, hyperacuity perimetry and visual acuity testing. The results were compared to the findings of the in-office comprehensive retina exam and OCT evaluation. Results: The foveal acuity potential registered with the Macustat test showed high correlation with the office Snellen acuity potential 96% of eyes registered Macustat acuity within 0.2 LogMAR of office acuity measurement. In Wet AMD eyes with CNV pathology documented on OCT, the Macustat foveal function scan showed a corresponding abnormality in 89% of any CNV eyes and 100% of all visually significant CNV. In normal eyes without any visually significant edema or CNV, more than 92% showed corresponding normal retinal function scan. Conclusion: The Macustat demonstrates high concordance with clinical findings using traditional diagnostic devices. Home monitoring with the Macustat® may offer complementary clinical utility as a telehealth tool for the assessment of visual acuity and macular function in patients at high risk for macular disease.

Cytomegalovirus retinitis after treatment with topical difluprednate in an aphakic eye of an immunocompetent patient.

PURPOSE: To report a case of an immunocompetent 64-year-old man who developed cytomegalovirus (CMV) retinitis after using topical difluprednate. OBSERVATIONS: A 64-year-old man with type 2 diabetes developed hemorrhagic retinitis while using topical difluprednate after penetrating keratoplasty. Polymerase chain reaction of the vitreous was positive for CMV DNA. Complete blood count was within normal limits and 4th generation human immunodeficiency virus assay was negative. The retinitis resolved with oral valgancyclovir and intravitreal foscarnet injections. CONCLUSION AND IMPORTANCE: CMV retinitis may occur after topical difluprednate in an immunocompetent patient.

Pain Control after Intravitreal Injection Using Topical Nepafenac 0.3% or Pressure Patching: A Randomized, Placebo-Controlled Trial.

PURPOSE: Pain after an intravitreal injection (IVI) can last up to 7 days and negatively impacts the patient's experience, potentially reducing treatment compliance. We prospectively evaluated topical nepafenac 0.3% suspension and patching for the reduction of pain after IVI. DESIGN: Randomized controlled trial. PARTICIPANTS: Sixty patients receiving an IVI of bevacizumab, aflibercept, or triamcinolone acetonide in 1 eye. METHODS: Participants were randomized equally to receive either a single drop of nepafenac 0.3%, a pressure patch for 2 hours, or a single drop of preservative-free artificial tears (control group). A single-blinded placebo-controlled design was used to mask the topical treatment used. Pain was assessed using the Numeric Pain Rating Scale that ranged from 0 to 10 (horizontal pain scale). Because pain scores were not normally distributed, statistical analysis was performed using a nonparametric randomization-based analysis of covariance. MAIN OUTCOME MEASURE: Pain scores. RESULTS: Fifty-six and 53 patients of the 60 patients enrolled completed the 6- and 24-hour follow-ups, respectively. Numeric Pain Rating Scale scores at 6 and 24 hours after IVI were lower in the nepafenac group (0.8±0.3 and 0.1±0.1, respectively; n = 18) and the patching group (1.3±0.4 and 0.4±0.2, respectively; n = 19) compared with the control group (2.5±0.6 and 0.9±0.4, respectively; n = 19). After controlling for age, gender, number of prior injections, and physician administering the injection, patients in the nepafenac group reported significantly lower pain scores than those in the control group at 6 hours (1.3±0.6 less; P = 0.047) and 24 hours (0.7±0.3 less; P = 0.047). Although the patching group reported lower pain scores than the control group, this was not statistically significant (6 hours, P = 0.24; 24 hours, P = 0.29). CONCLUSIONS: Nepafenac 0.3% was effective as a single drop in reducing pain at 6 and 24 hours after IVI compared with placebo. Limited patching was associated with lower pain scores than placebo, but the difference was not statistically significant. Additional studies are needed to determine the most effective method to maximize the patient's experience after an IVI without sacrificing outcomes.

SILDENAFIL CITRATE INDUCED RETINAL TOXICITY-ELECTRORETINOGRAM, OPTICAL COHERENCE TOMOGRAPHY, AND ADAPTIVE OPTICS FINDINGS.

BACKGROUND/PURPOSE: To report a case of persistent retinal toxicity associated with a high dose of sildenafil citrate intake. METHODS: Single retrospective case report. RESULTS: A 31-year-old white man with no medical history presented with complaints of bilateral multicolored photopsias and erythropsia (red-tinted vision), shortly after taking sildenafil citrate-purchased through the internet. Patient was found to have cone photoreceptor damage, demonstrated using electroretinogram, optical coherence tomography, and adaptive optics imaging. The patient's symptoms and the photoreceptor structural changes persisted for several months. CONCLUSION: Sildenafil citrate is a widely used erectile dysfunction medication that is typically associated with transient visual symptoms in normal dosage. At high dosage, sildenafil citrate can lead to persistent retinal toxicity in certain individuals.

Vitreous Occlusion of a Glaucoma Drainage Implant-Surgical Management.

Vitreous occlusion of a glaucoma drainage implant (GDI) can lead to failure of the device and severely elevated intraocular pressure. The pathophysiology of tube obstruction is related to central and anterior displacement of vitreous that is drawn into and condenses within the proximal lumen of the tube. This can occur from days to years following GDI surgery. Successful management of vitreous-tube obstruction generally requires manual removal of the condensed vitreous plug with end-grasping forceps. This technique achieves reversal of tube blockage and restoration of GDI function. Amputation of the incarcerated vitreous alone with vitrectomy or neodymium:yttrium-aluminum-garnet vitreolysis does not consistently restore GDI function and risks persistent intraluminal tube obstruction.

Corneal abrasion following anaesthesia for non-ocular surgical procedures: A case-controlled study.

The aim of this study was to identify risk factors associated with perioperative corneal abrasion at a single hospital in Mineola, New York (United States). A chart review was conducted of patients with perioperative corneal abrasion following non-ocular surgery and age-matched controls between June 2011 and November 2013. An age-stratified logistic regression model evaluated the association between corneal abrasion and potentially predisposing variables. The adjusted odds of a corneal abrasion occurring were 4.6 times greater for patients having surgery for ≥ 3 hours (p=0.001) and 3.6 times greater for patients with pre-existing ocular disease (p=0.02). Gender, diabetes status, surgical procedure or position were not found to be associated with the occurrence of a corneal abrasion. Corneal abrasions were associated with longer procedures and history of pre-existing ocular disease. No significant association between body positioning or surgical site and perioperative corneal abrasion was found. The study concludes that a longer duration of surgical procedure and pre-existing ocular disease are risk factors for perioperative corneal abrasion.

Clinical outcomes and antibiotic susceptibilities of Staphylococcus aureus endophthalmitis.

PURPOSE: To compare the antibiotic susceptibilities and visual acuity (VA) outcomes in endophthalmitis caused by methicillin-resistant (MRSA) versus methicillin-sensitive S. aureus (MSSA). METHODS: The records of 34 cases of S. aureus endophthalmitis at The New York Eye and Ear Infirmary from Jan 1997 to June 2011 were reviewed. Antibiotic susceptibility profiles over time and VA at presentation and at 3, 6, and ≥12 months were recorded. S. aureus isolates were grouped based on oxacillin resistance. RESULTS: Of the 34 cases, 15 (44 %) were MRSA and 19 (56 %) MSSA. Median presenting VA was hand motions (logMAR 4.0) in both the MRSA and MSSA groups. There was no statistically significant difference in VA between the MRSA and MSSA groups at 3, 6, or ≥12 months. No MRSA isolates were resistant to vancomycin or gentamicin. While over 85 % of MRSA isolates tested for fourth-generation fluoroquinolones were resistant, just 10 % MSSA isolates tested were resistant. There was a trend suggesting an increase in the proportion of MRSA isolates compared to MSSA isolates over the course of the study period. CONCLUSIONS: There was no statistical difference in short- or long-term VA outcomes between the MRSA and MSSA groups at any time point. Resistance to fourth-generation fluoroquinolones was present in over 85 % of MRSA isolates, but just 10 % of MSSA isolates. An increasing proportion of MRSA amongst S. aureus isolates was noted over the course of the study period.

Long-term Outcomes and Complications of Pars Plana Baerveldt Implantation in Children.

PURPOSE OF THE STUDY: The purpose of the study was to report long-term outcomes and complications of Baerveldt glaucoma implant (BGI) surgery with pars plana tube insertion in children. MATERIALS AND METHODS: The medical records of consecutive aphakic and pseudophakic children (<16 y of age) who underwent BGI surgery with pars plana tube insertion between 1990 and 2013 were retrospectively reviewed. Main outcome measures were intraocular pressure and number of glaucoma medications. Postoperative complications were recorded. Failure was defined as an intraocular pressure <5 or ≥21 mm Hg (with or without glaucoma medications), loss of light perception, or need for additional glaucoma surgery. RESULTS: Thirty-seven children were identified with a mean age of 6.0±4.7 years (range, 4 mo to 14.5 y). Mean follow-up after pars plana BGI surgery was 6.5±3.4 years (range, 9 mo to 12.8 y) for patients who met success criteria. Mean intraocular pressure and mean number of glaucoma medications at most recent follow-up for patients with successful intraocular pressure control were 13.8±4.1 and 2.3±1.9 mm Hg, respectively. The Kaplan-Meier survival analysis revealed 1-, 3-, 5-, and 7-year success rates of 94.5%, 74.6%, 65.0%, and 45.8%, respectively. Complications included tube exposure in 1 patient (2.7%), tube obstruction in 8 patients (21.6%), and retinal detachment in 9 patients (24.3%). Seventeen patients (45.9%) failed due to inadequate intraocular pressure control, of whom 9 (24.3%) required additional glaucoma surgery. CONCLUSIONS: Although pars plana BGI surgery is a reasonable option for managing refractory glaucoma in aphakic and pseudophakic children, surgeons must be aware of the potential need for additional glaucoma surgery and/or posterior segment complications with extended follow-up.

PERFLUOROCARBON LIQUIDS' ABILITY TO PROTECT THE MACULA FROM INTRAOCULAR DROPPING OF METALLIC FOREIGN BODIES: A Model Eye Study.

PURPOSE: To examine the utility of perfluoro-n-octane (PFO) in balanced salt solution (BSS) to shield the macula from the impact of dropped metallic intraocular foreign bodies (IOFBs) by modeling scenarios in which they may fall during surgical removal. METHODS: Model eyes were filled with various fluid mixtures (Group 1: 10% PFO/90% BSS; Group 2: 100% BSS; Group 3: 100% PFO; Group 4: 10% PFO/90% air; Group 5: 10% BSS/90% air). In Groups 1, 4, and 5, the 10% fluid volume covered the theoretical macula. For each fluid mixture, up to 30 IOFB drop scenarios were performed for each of the 5 sample IOFBs from 3 locations. Trajectories were recorded using a camera attached to a Zeiss operating microscope (Carl Zeiss, Jena, Germany). The percentages of IOFBs impacting the macula were calculated and Fisher exact test was used to assess differences. RESULTS: In Group 1, 93% (417/450) of the dropped IOFBs were deflected by the PFO-BSS interface compared with 0% (0/500) in Groups 2, 3, 4, and 5 (P < 0.01). With the exception of the heaviest IOFB (24.4 mg), which impacted the macula in 30% of tests when dropped from the superior posterior segment (P < 0.01), all other IOFBs (2.8-13.4 mg) were deflected by the PFO-BSS interface in 100% of Group 1 drops (P < 0.01). CONCLUSION: As demonstrated by these simulations, the PFO-BSS interface can deflect IOFBs dropped during surgery in a wide range of scenarios, especially when the IOFB is of lower mass.

RETINAL VASCULAR PERFUSION DENSITY MAPPING USING OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY IN NORMALS AND DIABETIC RETINOPATHY PATIENTS.

PURPOSE: To describe a new method of retinal vascular perfusion density mapping using optical coherence tomography angiography and to compare current staging of diabetic retinopathy based on clinical features with a new grading scale based on perifoveal perfusion densities. METHODS: A retrospective review was performed on subjects with diabetic retinopathy and age-matched controls imaged with a spectral domain optical coherence tomography system (Optovue XR Avanti, Fremont, CA). Split-spectrum amplitude-decorrelation angiography (SSADA) generated optical coherence tomography angiograms of the superficial retinal capillaries, deep retinal capillaries, and choriocapillaris. Skeletonized optical coherence tomography angiograms were used to create color-coded perfusion maps and capillary perfusion density values for each image. Capillary perfusion density values were compared with clinical staging, and groups were compared using analysis of variance and Kruskal-Wallis analyses. RESULTS: Twenty-one control and 56 diabetic retinopathy eyes were imaged. Diabetic eyes were grouped according to clinical stage. Capillary perfusion density values from each microvascular layer were compared across all groups. Capillary perfusion density values were significantly lower in nearly all layers of all study groups compared with controls. Trend analysis showed a significant decrease in capillary perfusion density values as retinopathy progresses for most layers. CONCLUSION: Quantitative retinal vascular perfusion density mapping agreed closely with grading based on clinical features and may offer an objective method for monitoring disease progression in diabetic retinopathy.

Spontaneous Dissociation of Fluocinolone Acetonide Sustained Release Implant (Retisert) with Dislocation into the Anterior Chamber.

PURPOSE: To report two cases of spontaneous Retisert implant dissociation with dislocation of the medication reservoir into the anterior chamber. DESIGN AND METHODS: Case reports. RESULTS: Two patients with chronic, noninfectious uveitis following Retisert implantation between 6 and 7 years prior presented with a complaint of a "white spot" in their right eyes. Both patients had previous pars plana vitrectomies. Anterior segment examination revealed a dislocated medication reservoir of the Retisert implant in the inferior portion of anterior chamber with associated reservoir-corneal endothelial touch and stromal edema. The reservoirs were subsequently retrieved via a pars plana approach and removed from the anterior chamber through a corneal incision. CONCLUSIONS: Spontaneous dissociation of the Retisert implant with dislocation of the medication reservoir into the anterior chamber can be a late complication of Retisert implantation. Eye care professionals and patients should be aware of this complication, particularly with long-term intraocular retention of this device.

Assessment of perfused foveal microvascular density and identification of nonperfused capillaries in healthy and vasculopathic eyes.

PURPOSE: To analyze the foveal microvasculature of young healthy eyes and older vasculopathic eyes, imaged using in vivo adaptive optics scanning light ophthalmoscope fluorescein angiography (AOSLO FA). METHODS: AOSLO FA imaging of the superficial retinal microvasculature within an 800-µm radius from the foveal center was performed using simultaneous confocal infrared (IR) reflectance (790 nm) and fluorescence (488 nm) channels. Corresponding IR structural and FA perfusion maps were compared with each other to identify nonperfused capillaries adjacent to the foveal avascular zone. Microvascular densities were calculated from skeletonized FA perfusion maps. RESULTS: Sixteen healthy adults (26 eyes; mean age 25 years, range, 21-29) and six patients with a retinal vasculopathy (six eyes; mean age 55 years, range, 44-70) were imaged. At least one nonperfused capillary was observed in five of the 16 healthy nonfellow eyes and in four of the six vasculopathic eyes. Compared with healthy eyes, capillary nonperfusion in the vasculopathic eyes was more extensive. Microvascular density of the 16 healthy nonfellow eyes was 42.0 ± 4.2 mm(-1) (range, 33-50 mm(-1)). All six vasculopathic eyes had decreased microvascular densities. CONCLUSIONS: AOSLO FA provides an in vivo method for estimating foveal microvascular density and reveals occult nonperfused retinal capillaries. Nonperfused capillaries in healthy young adults may represent a normal variation and/or an early sign of pathology. Although limited, the normative data presented here is a step toward developing clinically useful microvascular parameters for ocular and/or systemic diseases.

Role of Intravitreal Antivascular Endothelial Growth Factor Injections for Choroidal Neovascularization due to Choroidal Osteoma.

We treated 26 eyes of 25 young patients having a mean age of 30 years with intravitreal vascular endothelial growth factor (VEGF) inhibitor for choroidal new vessel (CNV) formation overlying choroidal osteoma over a mean follow-up of 26 months. Mean number of injections was 2.4 at 6 months, 3.2 at 12 months, and 5.5 at 24 months. CNV was subfoveal in 14 eyes, juxtafoveal in 5, extrafoveal in 5, and peripapillary in 2. By paired comparison, mean decrease from baseline was 119.7 microns at 6 months (n = 15; P = 0.001), 105.3 microns at 1 year (n = 10; P = 0.03), and 157.6 microns at 2 years (n = 7; P = 0.08). BCVA improved by 3.3 lines at 6 months after therapy (n = 26; P < 0.001), 2.8 lines (n = 20; P = 0.01) at 1 year, and 3.1 lines (n = 13; P = 0.049) at 2 years. We conclude that intravitreal anti-VEGF injections improve vision in majority of eyes with CNV from choroidal osteoma.