Obtaining High-Quality Cryosections of Whole Rabbit Eye

This protocol describes how to obtain high-quality retinal cryosections in larger animals, such as rabbits. After enucleation, the eye is briefly immersed in the fixative. Then, the cornea and iris are removed and the eye is left overnight for additional fixation at 4 °C. Following fixation, the lens is removed. The eye is then placed in a cryomold and filled with an embedding medium. By removing the lens, the embedding medium has better access to the vitreous and leads to better retinal stability. Importantly, the eye should be incubated in embedding medium overnight to allow complete infiltration throughout the vitreous. Following overnight incubation, the eye is frozen on dry ice and sectioned. Whole retinal sections may be obtained for use in immunohistochemistry. Standard staining protocols may be utilized to study the localization of antigens within the retinal tissue. Adherence to this protocol results in high-quality retinal cryosections that may be used in any experiment utilizing immunohistochemistry.

Macular Sling: A Customizable Method for Macular Buckling using Available Elements

PURPOSE

Macular buckling surgery is used to treat certain cases of myopic traction maculopathy but is rarely performed in the United States. One of the main factors limiting its use is the lack of commercially available buckling elements. Here we describe a novel technique for creating an effective macular buckle using readily obtainable buckling materials.

METHODS

By using a traditional circumferential 41 band as the anchoring point around the globe, a 240 band can then be attached and oriented posteriorly along the superonasal-infertemporal axis. This posterior 240 band is then used to guide a grooved sponge (509G) under the macula to create a customizable and titratable tamponade effect along the posterior pole. This approach was used to provide external support in the case of a recurrent, complex tractional retinal detachment which had failed multiple prior vitrectomy-based repairs.

RESULTS

Placement of the macular sling resolved the patient's recurrent retinal detachment with return of visual acuity to her pre-operative baseline. There have been no adverse effects related to the surgery aside from a large hyperopic shift due to the buckle effect on the macula. We believe the technical and material complexity of this technique is comparable to that of more common scleral buckling techniques.

CONCLUSIONS

This macular sling technique can be used to create an effective posterior buckle without requiring specialized materials.

Patient and Provider Experience in Real-Time Telemedicine Consultations for Pediatric Ophthalmology

Purpose

Telemedicine adoption hinges on positive experiences for patients and providers. We report participants’ experience from our prospective study.

Patients and Methods

Ophthalmic examinations for children 0–17 years of age were conducted by an optometrist using digital exam instruments and streamed to an ophthalmologist. The ophthalmologist, optometrist, parent, and patient (≥10 years) completed surveys capturing patient and provider experience outcomes.

Results

Three hundred forty-eight examinations were conducted with 210 patients in a hospital-based pediatric ophthalmology clinic. About 99% of parents were comfortable with exam quality, and 97% indicated they would have another telemedicine examination. Fifty-four of 55 consented for surgery during the initial telemedicine examination. Thirty-seven percent of families traveled ≥2 hours round-trip to their appointment; 1/3 of parents and patients missed a full day of work/school. Video glasses were by far the most useful instrument, while technical proficiency was most challenging with the digital indirect ophthalmoscope. Problem-focused examinations took 33 minutes of the ophthalmologist’s time on average. Equipment challenges caused delays in 40/348 (11.5%) of visits, with the majority lasting 5–10 minutes. In a few cases, a backup device was used. Despite seeing significantly fewer patients on telemedicine days, the ophthalmologist’s surgical volume increased 25%.

Conclusion

All participants were satisfied with telemedicine visits despite longer durations and learning curve. Results indicate an opportunity for telemedicine in community settings to improve access to specialized care. Telemedicine enabled the optometrist to manage or co-manage more complex patients with a pipeline to the ophthalmologist for surgical cases. In the right setting, collaborative telemedicine consultations may be beneficial to one’s practice.

Wedge Defects on Optical Coherence Tomography Angiography of the Peripapillary Retina in Glaucoma: Prevalence and Associated Clinical Factors

PRCIS

Among subjects with glaucoma, wedge-shaped defects on optical coherence tomography angiography (OCTA) were associated with disc hemorrhages (DH), paracentral visual field (VF) defects, increased cup-to-disc ratio (CDR), and thinner retinal nerve fiber layer (RNFL).

PURPOSE

To examine determinants of wedge defects on peripapillary OCTA in glaucoma.

MATERIALS AND METHODS

A total of 278 eyes of 186 subjects with mild to severe primary open-angle glaucoma underwent 6×6 spectral-domain OCTA imaging of the superficial peripapillary retina from 2016 to 2020 at an academic practice. Wedge defects were defined as focal microvasculature loss that extends outward from the optic nerve in an arcuate, wedge shape. Logistic regression models controlling for intereye correlation identified variables significantly associated with wedge defects. Eyes with profound microvasculature loss in both hemispheres were excluded. Candidate variables included: age, sex, race or ethnicity, diabetes, hypertension, follow-up duration, baseline untreated intraocular pressure, intraocular pressure at time of imaging, DH history, paracentral VF defects, CDR, central corneal thickness, spherical equivalent, VF mean deviation, RNFL thickness, and glaucoma stage.

RESULTS

Of 278 eyes, 126 (45.3%) had wedge defects in at least 1 hemisphere. In our multivariable logistic regression model, wedge defects were associated with DH history [odds ratio (OR): 3.19, 95% confidence interval (CI): 1.05-9.69, P=0.041], paracentral VF defects [OR: 4.38 (95% CI: 2.11-9.11), P<0.0001], larger CDR [OR: 1.27 (95% CI: 1.03-1.56), P=0.024, per 0.1 increase], and thinner RNFL [OR: 1.71 (95% CI: 1.25-2.34), P=0.0009, per 10 μm decrease].

CONCLUSION

DH history and paracentral VF defects were independently associated with wedge defects on OCTA, which was present in 45.3% of primary open-angle glaucoma patients. These findings may provide insight into glaucoma pathogenesis.

Provider-to-provider synchronous telemedical consultations in ophthalmology: Advice for implementation

We previously demonstrated the non-inferiority of a synchronous (real-time) telemedicine model (compared to gold standard in-person examination) for pediatric ophthalmology consultations using a Polycom conferencing system, smart glasses, digital slit lamp, and digital indirect ophthalmoscope. Although we acknowledge there is a learning curve associated with becoming proficient with this system, we believe implementation of a synchronous telemedicine model is advantageous to both patient and provider in the right care setting. In conducting 348 such examinations over the course of our study and dozens of subsequent examinations after the implementation of our model in the community, we have gleaned many insights into optimizing the experience and efficiency. We wish to share these insights to help guide those interested in adopting such a model to expand access to specialists for underserved patients or improve efficiencies in their practice.

Feasibility of asynchronous video-based telemedicine in the diagnosis and management of paediatric blepharoptosis

INTRODUCTION

The purpose of this study was to assess the validity of using video glasses as part of an asynchronous telemedicine screening protocol for paediatric blepharoptosis.

METHODS

A physician assistant wearing Pivothead SMART Series glasses recorded videos of paediatric patients referred for blepharoptosis in primary, down and upgaze while holding a ruler next to the eyes. An oculoplastic surgeon viewed the stored videos and recorded margin-reflex distance 1 and levator function. Using these measurements, the surgeon determined whether surgical intervention was recommended and, if so, which procedure was recommended. The surgeon recorded the same parameters for each patient based on an in-person examination performed later that day. Videos were reviewed eight months later and the same parameters were recorded.

RESULTS

Twenty-nine children (n = 58 eyes) were enrolled. Margin-reflex distance 1 and levator function measurements based on same-day video review agreed with in-person examination 94.8% (intraclass correlation coefficient = 0.82) and 98.3% (intraclass correlation coefficient = 0.96) of the time, respectively. Margin-reflex distance 1 and levator function measurements based on later video review agreed with in-person examination 93.1% (intraclass correlation coefficient = 0.85) and 94.8% (intraclass correlation coefficient = 0.93) of the time, respectively. Agreement in identifying surgical candidates was almost perfect (= = 0.93) for same-day video review and substantial (= = 0.73) for later video review. Sensitivity of identifying surgical patients was 100% for both same-day video review and later video review; though specificity was lower at 94.1% for same-day video review and 76.5% for later video review.

DISCUSSION

Asynchronous telemedicine encounters employing video glasses are a useful screening modality for identifying surgical paediatric blepharoptosis patients.