Optometry Commons^™

Optical Coherence Elastography Measures The Biomechanical Properties Of The Ex Vivo Porcine Cornea After Lasik, Achuth Nair, Fernando Zvietcovich, Manmohan Singh, Mitchell P Weikert, Salavat R Aglyamov, Kirill V Larin

Faculty, Staff and Students Publications

SIGNIFICANCE: The biomechanical impact of refractive surgery has long been an area of investigation. Changes to the cornea structure cause alterations to its mechanical integrity, but few studies have examined its specific mechanical impact.

AIM To quantify how the biomechanical properties of the cornea are altered by laser assisted in situ keratomileusis (LASIK) using optical coherence elastography (OCE) in ex vivo porcine corneas.

APPROACH: Three OCE techniques, wave-based air-coupled ultrasound (ACUS) OCE, heartbeat (Hb) OCE, and compression OCE were used to measure the mechanical properties of paired porcine corneas, where one eye of the pair was left untreated, and the …

Atypical Haemorrhagic Presentation Of Neuro-Retinitis And Serous Retinal Detachment Secondary To Cat-Scratch Disease, Henry C Skrehot, Amer F Alsoudi, Ryan P Nolan, Adam J Cantor, Asad Loya, Rod Foroozan

Faculty, Staff and Students Publications

Cat-scratch disease (CSD) is a self-limited disease caused by Bartonella henselae, a fastidious gram-negative intracellular bacillus bacterium. Neuroretinitis, a form of optic neuropathy characterised clinically by optic disc swelling and a macular star, is an uncommon manifestation of CSD occurring in approximately 1-2% of cases. We report a case of a 14-year-old female who presented to the emergency department with a chief complaint of acute painless vision loss described as a large black spot in the centre of her right eye vision 2 weeks after being scratched by cats. Fundus examination revealed Frisen grade 5 disc oedema with an …

The Co-Expression Of The Depolarizing And Hyperpolarizing Mechanosensitive Ion Channels In Mammalian Retinal Neurons, Vivian Y Pang, Zhuo Yang, Samuel M Wu, Ji-Jie Pang

Faculty, Staff and Students Publications

Introduction

The elevation of the intraocular and extraocular pressures is associated with various visual conditions, including glaucoma and traumatic retinal injury. The retina expresses mechanosensitive channels (MSCs), but the role of MSCs in retinal physiology and pathologies has been unclear.

Methods

Using immunocytochemistry, confocal microscopy, and patch-clamp recording techniques, we studied the co-expression of K⁺-permeable (K-MSCs) TRAAK and big potassium channel BK with the epithelial sodium channel ENaC and transient receptor potential channel vanilloid TPRV4 and TRPV2 favorably permeable to Ca²⁺ than Na⁺ (together named N-MSCs), and TRPV4 activity in the mouse retina.

Results

TRAAK immunoreactivity …

Analysis Of Macular Pigment Carotenoids In Human Blood Serum Of Glaucoma Patients As A Measure Of Ocular Health: A Raman Spectroscopic Study., Joy Udensi, Ekaterina Loskutova, James Loughman, Hugh J. Byrne

Datasets

Carotenoids are a major component of the human diet and have been widely studied for their antioxidant, and vision protection roles in the human body, and dietary supplementation is promoted in particular for ocular health. An initial trial (European Nutrition in Glaucoma Management (ENIGMA)), which assessed macular pigment optical density (MPOD) as well as ocular structural, functional and perceptual parameters before and after the 18-month supplementation of glaucoma patients with macular pigment (MP) carotenoids (lutein, zeaxanthin, meso-zeaxanthin), confirmed supplementation significantly improved the clinical ocular health of participants. Blood contains all major dietary carotenoids, presenting it as a suitable and efficient …

Quantitative Raman Analysis Of Human Blood Serum Of Glaucoma Patients Supplemented With Macular Pigment Carotenoids., Joy Udensi, Ekaterina Loskutova, James Loughman, Hugh J. Byrne

Datasets

Carotenoids have been widely studied for their high dietary, antioxidant, and vision protection roles in the human body. Blood contains all major dietary carotenoids and hence presents as a suitable and efficient substrate for the estimation of dietary carotenoids in vivo. Following the 18-month supplementation of open angle glaucoma patients with macula pigment carotenoids (Lutein, Zeaxanthin and Meso-Zeaxanthin) in the European Nutrition in Glaucoma Management (ENIGMA) trial, Raman spectroscopic analysis of the pre-supplementation baseline and 18-month supplemented blood serum carotenoids from participants was carried out, to investigate the systemic impact of supplementation in the blood and explore a more direct …

Trpv4 Affects Visual Signals In Photoreceptors And Rod Bipolar Cells, Ye Long, Maxim Kozhemyakin, Samuel M Wu, Ji-Jie Pang

Faculty, Staff and Students Publications

INTRODUCTION: Mechanical sensitive channels expressed in mammalian retinas are effectors of elevated pressure stresses, but it is unclear how their activation affects visual function in pressure-related retinal disorders.

METHODS: This study investigated the role of the transient potential channel vanilloid TRPV4 in photoreceptors and rod bipolar cells (RBCs) with immunohistochemistry, confocal microscopy, electroretinography (ERG), and patch-clamp techniques.

RESULTS: TRPV4 immunoreactivity (IR) was found in the outer segments of photoreceptors, dendrites and somas of PKCα-positive RBCs and other BCs, plexiform layers, and retinal ganglion cells (RGCs) in wild-type mice. TRPV4-IR was largely diminished in the retinas of homozygous TRPV4 transgenic mice. …

Single Cell Analysis Of Short-Term Dry Eye Induced Changes In Cornea Immune Cell Populations, Jehan Alam, Ebru Yaman, Gerda Cristal Villalba Silva, Rui Chen, Cinita S De Paiva, Mary Ann Stepp, Stephen C Pflugfelder

Faculty, Staff and Students Publications

BACKGROUND: Dry eye causes corneal inflammation, epitheliopathy and sensorineural changes. This study evaluates the hypothesis that dry eye alters the percentages and transcriptional profiles of immune cell populations in the cornea.

METHODS: Desiccating stress (DS) induced dry eye was created by pharmacologic suppression of tear secretion and exposure to drafty low humidity environment. Expression profiling of corneal immune cells was performed by single-cell RNA sequencing (scRNA-seq). Cell differentiation trajectories and cell fate were modeled through RNA velocity analysis. Confocal microscopy was used to immunodetect corneal immune cells. Irritation response to topical neurostimulants was assessed.

RESULTS: Twelve corneal immune cell populations …

The Utility Of Software-Detected Non-Invasive Tear Break-Up In Comparison To Fluorescein Tear Break-Up Measurements, Stephen C Pflugfelder, Yasushi Kikukawa, Shin Tanaka, Takuya Kosugi

Faculty, Staff and Students Publications

PURPOSE: The purpose of this study is to characterize and discuss the difference between software-detected non-invasive tear break-up time (NIBUT) and the traditional clinical method of fluorescein break-up time (FBUT).

METHODS: Tear interferometry with the KOWA DR-1α (Kowa, Japan) and a standardized comprehensive ocular surface/tear evaluation were performed in 307 eyes. Software-detected NIBUT in the KOWA DR-1α images and the investigator-detected FBUT were compared.

RESULTS: Software-detected NIBUT was significantly shorter than investigator-measured FBUT. NIBUT was 3.1 ± 2.5 s (mean ± SD), whereas FBUT was 4.8 ± 3.0 s. This difference was due to three different patterns or conditions: a …

Raman Microspectroscopy For Detection Of Oral Potentially Malignant Disorders Using Minimally Invasive Brush Biopsy Samples, Isha Behl

Doctoral

Oral cancer is one of the most common cancers worldwide. The current gold standard for screening and diagnosis of oral premalignant and cancerous lesions is histopathological examination. Subjectivity is a major limitation of this technique, however. Other diagnostic methods exist, but they are not sensitive enough for early detection of potentially malignant disorders (PMDs), as these methods are based on morphological changes, which can occur late in malignant transformation. Raman spectroscopy, on the other hand, can provide molecular level information of the biological sample, through unique vibrational fingerprints of molecules. This is advantageous over the gold standard method, as molecular …

Altered Outer Retinal Structure, Electrophysiology And Visual Perception In Parkinson's Disease, Katie K N Tran, Pei Ying Lee, David I Finkelstein, Allison M Mckendrick, Bao N Nguyen, Bang V Bui, Christine T O Nguyen

Faculty, Staff and Student Publications

BACKGROUND: Visual biomarkers of Parkinson's disease (PD) are attractive as the retina is an outpouching of the brain. Although inner retinal neurodegeneration in PD is well-established this has overlap with other neurodegenerative diseases and thus outer retinal (photoreceptor) measures warrant further investigation.

OBJECTIVE: To examine in a cross-sectional study whether clinically implementable measures targeting outer retinal function and structure can differentiate PD from healthy ageing and whether these are sensitive to intraday levodopa (L-DOPA) dosing.

METHODS: Centre-surround perceptual contrast suppression, macular visual field sensitivity, colour discrimination, light-adapted electroretinography and optical coherence tomography (OCT) were tested in PD participants (n = …

Strategies To Enhance Remote Monitoring Adherence Among Patients With Cardiovascular Implantable Electronic Devices, Thomas L Rotering, Sylvia J Hysong, Katherine E Williams, Merritt H Raitt, Mary A Whooley, Sanket S Dhruva

Faculty, Staff and Students Publications

BACKGROUND: Remote monitoring (RM) of patients with cardiovascular implantable electronic devices (CIEDs) (pacemakers and implantable cardioverter-defibrillators) has a Class 1, Level of Evidence A Heart Rhythm Society recommendation. Yet RM adherence varies widely across settings, and factors associated with variation are not understood.

OBJECTIVE: The purpose of this study was to identify strategies for supporting RM across Veterans Health Administration (VHA) facilities.

METHODS: In a national evaluation, we surveyed and interviewed 27 nurses, medical instrument technicians, and advanced practice providers across 26 VHA facilities (following approximately 15,000 CIED patients). Participants were selected based on overall patient adherence by facility, which …

Idiopathic Intracranial Hypertension: A Case Report, Christopher Bugajski Od

Optometric Clinical Practice

Background: Optic nerve head edema is a serious finding for which multiple etiologies need to be considered. When optic nerve head edema is observed bilaterally, among the top differentials is idiopathic intracranial hypertension (IIH), also known as primary pseudotumor cerebri. An emergent magnetic resonance image with and without contrast as well as venography and lumbar puncture with opening pressure measurement must be performed to diagnose and determine management. Case Report: This case specifically features a 30-year-old Caucasian female with bilateral optic disc edema secondary to IIH. In addition to discussing the details regarding this patient’s case, this report …

The Atoh1-Cre Knock-In Allele Ectopically Labels A Subpopulation Of Amacrine Cells And Bipolar Cells In Mouse Retina, Sih-Rong Wu, Huda Y Zoghbi

Duncan NRI Faculty and Staff Publications

The retina has diverse neuronal cell types derived from a common pool of retinal progenitors. Many molecular drivers, mostly transcription factors, have been identified to promote different cell fates. In Drosophila, atonal is required for specifying photoreceptors. In mice, there are two closely related atonal homologs, Atoh1 and Atoh7. While Atoh7 is known to promote the genesis of retinal ganglion cells, there is no study on the function of Atoh1 in retinal development. Here, we crossed Atoh1^Cre/+ mice to mice carrying a Cre-dependent TdTomato reporter to track potential Atoh1-lineage neurons in retinas. We characterized a heterogeneous …

Pituitary Adenoma Hidden By Comorbid Cataract, Len Koh Od, Megan E. Mcchesney Od, Chad E. Gosnell Od

Optometric Clinical Practice

Background: A pituitary adenoma is an abnormal growth in the pituitary gland. Pituitary adenomas are the most common cause of sellar masses accounting for approximately 10% of all intracranial neoplasms. Early visual symptom of pituitary adenoma can be hidden by comorbid cataract in elderly patients. Case Report: A 74 y.o. male presented to the eye clinic with blurry vision at all distances and has trouble with glare from lights. His best corrected visual acuity (BCVA) was 20/20^-1 OD, 20/25^-2 OS, but subjectively of poor quality. Slit lamp exam confirmed mild nuclear sclerotic cataract OU and normal fundus exam. …

Sagging Eye Syndrome--An Overlooked Diagnosis, Zachary Tlumak Od, Theresa Zerilli-Zavgorodni Od, Nancy Shenouda-Awad Od

Optometric Clinical Practice

Abstract

Background: Sagging Eye Syndrome (SES) is a relatively unknown cause for binocular distance diplopia. SES presents with an acquired comitant or non-comitant small angle esotropia and/or hypotropia commonly occurring in the elderly population. Inferior displacement of the lateral rectus secondary to age-related degeneration of orbital connective tissue and extraocular muscles appears to be responsible for the ocular misalignment. SES patients often present with new onset or progressively worsening distance diplopia, typically warranting neuroimaging. However, through understanding SES, eye care practitioners may identify these cases, avoiding unnecessary imaging studies. Case Report: A 90-year-old male presented with complaints of intermittent horizontal …

Autosomal Dominant Optic Atrophy Plus Syndrome, Aaron W. Case Od, Lovelee E. Sayomac Od, Matthew J. Anderson Od

Optometric Clinical Practice

Background: Dominant optic atrophy (DOA) is the most commonly encountered hereditary optic neuropathy in clinical practice and is the result of a mutation in the OPA1 or OPA3 genes encoding mitochondrial membrane proteins. The resultant mitochondrial dysfunction causes a distinct set of ophthalmic findings and may progress to extra-ocular systems known as OPA plus syndrome. We present a case of late-onset OPA plus syndrome encompassing both typical ophthalmic findings and the rarer extra-ocular findings. Case Report: A 41 year-old Caucasian male presents for a second opinion regarding a previously diagnosed traumatic optic neuropathy. Examination revealed decreased best-corrected acuities, …

Diagnosis And Management Of A Patient With Methicillin-Resistant Staphylococcus Aureus Conjunctivitis, Michael Chocky Od

Optometric Clinical Practice

Background : Methicillin-resistant Staphylococcus aureus (MRSA) infections are becoming more common. These infections can cause various ocular conditions including conjunctivitis. Conjunctival cultures are an important tool to assist with proper diagnosis and treatment of these infections. Case Report : A 61-year-old African American male presented with the complaint of redness and drainage from his eyes. With the assistance of conjunctival cultures, he was diagnosed with MRSA conjunctivitis. Treatment with vancomycin ultimately led to resolution of the condition. Conclusion : MRSA conjunctivitis should always be considered when a conjunctivitis is not responding to empirical therapy. Eye care professionals should be aware …

Pupil Involving Oculomotor Palsy- Examination, Cause And Outcome, Robert Binkley Od, Karen Neal Od

Optometric Clinical Practice

BACKGROUND: A patient with a third cranial nerve (CN III) palsy can be a stress inducing event for an optometrist due to the potentially life-threatening etiologies and infrequency of their presentation. The pathogenesis of a CN III palsy can vary from innocuous to life threatening. Palsy of the third cranial nerve results in an impairment of eye movement and / or pupillary response to light depending on the extent of the palsy. CASE REPORT: This case reviews a recent onset of a complete right oculomotor palsy. Literature of similar cases detail the likelihood of variable causes, and while a diagnostic …

The Art Of Prescribing Low Amounts Of Prism: Basic Clinical Applications, Leonard J. Press Od

Optometric Clinical Practice

Expanding the Box

It's How You Ask The Question....., Paul Freeman Od

Optometric Clinical Practice

Letter from the Editor