a-surgical-approach-for-optic-nerve-crush-in-a-rabbit-model

A Surgical Approach for Optic Nerve Crush in a Rabbit Model

Optic nerve crush (ONC) is an experimental technique used to model and study the mechanisms of optic neuropathies and potential therapeutic interventions. ...

Stanford University

Johns Hopkins University

Heterophoria describes the deviation of the optical axes in the absence of binocular fusion. Eye trackers (ET) can provide an objective assessment but are not broadly used clinically. We examined the feasibility of combining an infrared (IR) pass-filter, IR detector, and an off-the-shelf ET. The proposed setup was validated against the broadly used cover test (CT). Furthermore, the setup was used to examine whether testing conditions can affect the measurements.

Synchronization of a Removable Optical Element with an Eye Tracker: Test Case for Heterophoria Measurement.

To determine whether combining measures of retinal structure and function predicts need for intervention for diabetic retinopathy (DR) better than either modality alone.

Enhancing Risk Assessment in Patients with Diabetic Retinopathy by Combining Measures of Retinal Function and Structure.

To determine whether mask-induced redirected exhaled air through the superior mask gap contacts multiuse eyedrop bottles during drop administration and the efficacy of interventions to reduce such exposure.

Contamination of multiuse eyedrop bottles by exhaled air from patients wearing face masks during the COVID-19 pandemic: Schlieren imaging analysis.

Wavefront-guided laser in situ keratomileusis (WFG-LASIK) and small incision lenticule extraction (SMILE) are keratorefractive surgeries that can improve uncorrected visual acuity in myopic patients. Comparison of visual outcomes in myopic patients treated with LASIK and SMILE is needed.

Prospective, Randomized Contralateral Eye Comparison of Wavefront-Guided Laser In Situ Keratomileusis and Small Incision Lenticule Extraction Refractive Surgeries.

 Teleophthalmology has emerged as a convenient and cost-effective intervention to increase access to screening for diabetic retinopathy (DR), a disease that disproportionately affects socially disadvantaged communities. However, a few studies have directly compared the detection of eye disease by teleophthalmology between socially and geographically diverse communities. This study compared the rates and severity of diabetic eye disease, as detected by teleophthalmology, between safety net and non-Safety Net Hospitals (non-SNHs).  Retrospective chart review of patients screened for DR at county Safety Net Hospitals (SNHs) and non-SNHs in 150 cities and 30 states. The rates of DR, macular edema, suspected cataract, suspected glaucoma, and suspected age-related macular degeneration were compared. Relative risk and severity of disease in the county SNH population were calculated. Images were graded by the same group of IRIS readers, who used at least one image per eye with a 45° field centered between the optic disc and the macula. Participants with ungradable screening images were excluded.  Ninety-four thousand three hundred twenty-nine participants were screened for eye disease from September 1, 2016 to August 31, 2017. Among the screened participants (54% female; mean [SD] age, 58.7 [12.9] years), overall disease detection was 31% in the county SNH population and 23.6% in the non-SNH population. Compared with the non-SNH population, the county SNH population was twice as likely to screen positive for three or more concurrent eye conditions (1.2% vs. 0.7%) and had increased prevalence of DR (20.2% vs. 16.2%), macular edema (4.9% vs. 3.4%), suspected glaucoma (9.1% vs. 4.3%), suspected cataract (9.6% vs. 4.8%), and proliferative DR (2.1% vs. 1.0%).  Increased diabetic eye disease prevalence and severity among people seen at SNHs highlights the need for continued resources to screen, treat, and manage disease. Teleophthalmology continues to be an important tool in efforts to mitigate health inequities and address barriers faced by underserved communities.

Teleophthalmology and Inequities in Diabetic Eye Disease at Safety Net Hospitals.

Using small molecule drugs to treat eye diseases carries benefits of specificity, scalability, and transportability, but their efficacy is significantly limited by a fast intraocular clearance rate. Ocular drug implants (ODIs) present a compelling means for the slow and sustained release of small molecule drugs inside the eye. However, methods are needed to inject small molecule ODIs into animals with small eyes, such as mice, which are the primary genetic models for most human ocular diseases. Consequently, it has not been possible to fully investigate efficacy and ocular pharmacokinetics of ODIs. Here, we present a robust, cost-effective, and minimally invasive method called "mouse implant intravitreal injection" (MI3) to deliver ODIs into mouse eyes. This method will expand ODI research to cover the breadth of human eye diseases modeled in mice.

An intravitreal implant injection method for sustained drug delivery into mouse eyes.

Ocular drug implants (ODIs) are beneficial for treating ocular diseases. However, the lack of a robust injection approach for small-eyed model organisms has been a major technical limitation in developing ODIs. Here, we present a cost-effective, minimally invasive protocol to deliver ODIs into the mouse vitreous called Mouse Implant Intravitreal Injection (MI3). MI3 provides two alternative surgical approaches (air-pressure or plunger) to deliver micro-scaled ODIs into milli-scaled eyes, and expands the preclinical platforms to determine ODIs' efficacy, toxicity, and pharmacokinetics. For complete details on the use and execution of this protocol, please refer to Sun et al. (2021).

A protocol to inject ocular drug implants into mouse eyes.

To report the unusual case of a previously stable choroidal nevus, closely followed for over 15 years, which underwent malignant transformation into small choroidal melanoma with massive extrascleral extension.

Endoscopic enucleation and clinicopathologic correlation of a small choroidal melanoma hiding massive extrascleral extension.

The purpose of this study was to compare the subjective visual experience and ocular symptoms of fellow eyes treated with wavefront-optimized laser-assisted in situ keratomileusis (WFO-LASIK) and wavefront-guided laser-assisted in situ keratomileusis (WFG-LASIK).

Comparison of Subjective Visual Experiences and Ocular Symptoms After Wavefront-Guided and Wavefront-Optimized LASIK in a Prospective Fellow Eye Study.

Targeted drug delivery to the optic nerve head may be useful in the preclinical study and later clinical management of optic neuropathies, however, there are no FDA-approved drug delivery systems to achieve this. The purpose of this work was to develop an optic nerve head drug delivery technique.

Development of a novel SupraChoroidal-to-Optic-NervE (SCONE) drug delivery system.

We present a complicated case of mixed mechanism glaucoma in the setting of failed corneal transplant and aphakia. The patient was a 54-year old male with HLA B27 uveitis and prior open globe injury. He was left aphakic after cataract extraction and had a subsequent corneal transplant for bullous keratopathy. Due to elevated intraocular pressure in the setting of a failed corneal graft, the decision was made to insert a pars plana tube shunt and perform repeat penetrating keratoplasty as a combined case with the glaucoma, cornea, and retina services. We illustrate the surgical steps and decision making and in this complex case.

Glaucoma tube shunt surgery with repeat penetrating keratoplasty in an aphakic patient.

Choroidal neovascularization caused by age-related macular degeneration, among other diseases, causes significant visual impairment. Intravitreal therapeutics inhibiting vascular endothelial growth factor (VEGF) signaling have shown excellent safety and efficacy in regressing choroidal neovascularization and improving vision. Current US Food and Drug Administration (FDA)-approved treatments deliver these drugs into the vitreous cavity, even though choroidal neovascularization originates from aberrant signaling in the choroid.

Article	Year
Synchronization of a Removable Optical Element with an Eye Tracker: Test Case for Heterophoria Measurement. Translational vision science & technology\| PubMed ID: 32832245	2020
Enhancing Risk Assessment in Patients with Diabetic Retinopathy by Combining Measures of Retinal Function and Structure. Translational vision science & technology\| PubMed ID: 32908803	2020
Contamination of multiuse eyedrop bottles by exhaled air from patients wearing face masks during the COVID-19 pandemic: Schlieren imaging analysis. Journal of cataract and refractive surgery\| PubMed ID: 34468454	2021
Prospective, Randomized Contralateral Eye Comparison of Wavefront-Guided Laser In Situ Keratomileusis and Small Incision Lenticule Extraction Refractive Surgeries. American journal of ophthalmology\| PubMed ID: 34788593	2022
Teleophthalmology and Inequities in Diabetic Eye Disease at Safety Net Hospitals. Telemedicine journal and e-health : the official journal of the American Telemedicine Association\| PubMed ID: 34978959	2022
An intravitreal implant injection method for sustained drug delivery into mouse eyes. Cell reports methods\| PubMed ID: 35128514	2021
A protocol to inject ocular drug implants into mouse eyes. STAR protocols\| PubMed ID: 35141566	2022
Endoscopic enucleation and clinicopathologic correlation of a small choroidal melanoma hiding massive extrascleral extension. American journal of ophthalmology case reports\| PubMed ID: 36703903	2023
Comparison of Subjective Visual Experiences and Ocular Symptoms After Wavefront-Guided and Wavefront-Optimized LASIK in a Prospective Fellow Eye Study. American journal of ophthalmology\| PubMed ID: 36870589	2023
Development of a novel SupraChoroidal-to-Optic-NervE (SCONE) drug delivery system. Drug delivery\| PubMed ID: 39010743	2024
Glaucoma tube shunt surgery with repeat penetrating keratoplasty in an aphakic patient. American journal of ophthalmology case reports\| PubMed ID: 39263687	2024
Suprachoroidal Drug Delivery for VEGF Suppression in Wet AMD and Other Diseases With Choroidal Neovascularization. American journal of ophthalmology\| PubMed ID: 40280278	2025

Bryce Chiang

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