Ophthalmology Commons^™

Cavernous Wonders: Delving Into Cavernous Sinus Syndrome In Neuro-Ophthalmology, Anza Rizvi, Ba

inSIGHT

Cavernous sinus syndrome (CSS) is any disease process that affects the cavernous sinus. This syndrome is marked by a complex interplay of neurovascular symptoms, primarily due to the compression or dysfunction of the cranial nerves that traverse the cavernous sinus. Understanding the intricate details of this syndrome is critical to providing optimal care and improving patient outcomes.

Seeing Clearly: A Bright Future With Light Adjustable Intraocular Lenses For Presbyopia, Shady Mina, Bs

inSIGHT

Presbyopia, or the age-related decline in the ability to focus on near objects, is a common vision disorder that affects 1.8 billion people globally, with this number expected to increase to 2.1 billion by 2030.^1-4 A diminished accommodation response is the primary cause of presbyopia.¹ The eye has a very complex accommodation mechanism that permits people to distinctly see objects from various distances.^1,3 Even though the precise mechanism of accommodation is yet to be determined, the current evidence strongly supports Helmholtz’s theory, which claims that the thickness and curvature of the eye’s lens increase while its diameter …

Medical Missions, Ethical Considerations And The Future For Healthcare Delivery In Ophthalmology, Robert Medina, Ba

inSIGHT

Beginning hundreds of years ago, priests from Europe embarked on ‘medical missions’ with the goals of delivering care to the body, mind, and soul. Hundreds of years later, members of the United States healthcare system set out on humanitarian medical missions to provide medical assistance to communities in developing countries.¹ The concept of providing care internationally as a product of global social responsibility has become engrained in the United States healthcare system, and is popular among providers, trainees, and pre-medical students. In 2023, 21.8% (n = 3264) of matriculating medical students reported participating in international volunteer work, while 7.0% …

Chronic Progressive External Ophthalmoplegia, Bahram Pashaee, Mph, Bs

inSIGHT

Chronic progressive external ophthalmoplegia is an inherited or sporadic form of dystrophy that preferentially affects the extraocular muscles of the eye. While this dystrophy can manifest systemically, the extraocular muscles are commonly involved due to their constant metabolic demands and vulnerability to oxidative stress.¹ This preferential involvement of the eyelid levator muscle and extraocular muscles makes CPEO an important condition to consider in a differential diagnosis for eyelid asymmetry and double vision among other conditions such as myasthenia gravis, thyroid-associated ophthalmoplegia, and other mitochondrial myopathies.² This dystrophy tends to occur in the third or fourth decade of life. …

Macular Holes: Diagnosis, Treatment, And Complications, Ayra Khan, Bs

inSIGHT

Macular hole is a condition that affects the central visual field of the eye. Without prompt diagnosis and intervention, macular holes can progressively worsen, significantly impacting both vision and overall quality of life.

Cmv Retinitis: An Expert’S Perspective, Caitlyn Kwun, Ba

inSIGHT

Uveitis is a rare inflammatory disease with a prevalence of around 38 per 100,000 people and is the overall 5th leading cause of blindness in the developed world.^1,2 Uveitis is most commonly found in patients younger than 40 years of age, but it can occur in any age group with an etiology that varies within each age demographic.^1,3 While the etiology of certain forms of uveitis are not fully understood, there are some that are autoimmune in nature and others that are associated with systemic diseases such as sarcoidosis.⁴ Uveitis may be inflammatory or infectious. It may …

Bridging The Global Gap Of Blindness Through Artificial Intelligence - Exploring The Tools Of Ai To Address The Top Causes Of Blindness In Under-Resourced Communities Worldwide, Nathan Delacth, Bs

inSIGHT

Technological advancements have allowed us to submerge in a sea of innovation and excellence in medicine. Electronic health records transformed the healthcare landscape, improving portability of patient information while streamlining communication and fostering collaboration.¹ Imaging technologies, such as magnetic resonance imaging (MRI) and Optical computed tomography (OCT), granted us the ability to view internal structures using non-invasive methods. In a similar vein, artificial intelligence (AI) has emerged as an impactful force in various fields of medicine, and its influence on ophthalmology is no exception.

Evolution Of Lamellar Keratoplasty, Ishan Kasat, Bs

inSIGHT

Overview of Keratoplasty The evolution of corneal transplantation, or keratoplasty, has seen a paradigm shift from traditional penetrating keratoplasty (PKP) to the refined precision of lamellar keratoplasty (LK). Penetrating, or full thickness, keratoplasty is a replacement of all corneal layers: epithelium, Bowman's layer, stroma, Descemet's membrane, and endothelium.¹ Lamellar, or partial thickness, keratoplasty involves replacement of either epithelium and stroma (anterior lamellar) or Descemet’s membrane and endothelium (posterior lamellar).² From 1985 to 2004, over 95% of graft tissues were used for PKP. However, from 2005 to 2014, the percentage of PKP procedures decreased from 95% to 42%, while …

The Myopia Epidemic: Exploring The Pathology And Management Of The World’S Most Common Eye Disorder, Gabriella Baldassarre, Bs

inSIGHT

Myopia is the most common eye disorder in the world and an increasing cause of vision impairment in children.¹ Myopia is an imbalance in the refractive components of the eye and its length, leading to inaccurate focusing of light rays in front of the retina tissue instead of on it. There is a spectrum of severity of myopia, from mild nearsightedness to a more severe form known as high or degenerative myopia, which has the potential to cause vision loss and blindness. There is evidence of a developing myopia epidemic, with an estimated one-third of the world population affected …

Insight, Volume 4, Issue 1, 2024

inSIGHT

Contents

8 - The Myopia Epidemic: Exploring the Pathology and Management of the World’s Most Common Eye Disorder
By Gabriella Baldassare

15 - Evolution of Lamellar Keratoplasty
By Ishan Kasat

19 - Bridging the Global Gap of Blindness Through Artificial Intelligence
By Nathan Delacth

24 - CMV Retinitis: An Expert’s Perspective
By Caitlyn Kwun

29 - Macular Holes: Diagnosis, Treatment, and Complications
By Ayra Khan

36 - Chronic Progressive External Ophthalmoplegia
By Bahram Pashaee

39 - Medical Missions, Ethical Considerations, and the Future for Healthcare Delivery in Ophthalmology
By Robert Medina

43 - Shaping the Future of Vision: The Rise …

Deep-Learning-Based Group Pointwise Spatial Mapping Of Structure To Function In Glaucoma, Zhiqi Chen, Hiroshi Ishikawa, Yao Wang, Gadi Wollstein, Joel Schuman

Wills Eye Hospital Papers

PURPOSE: To establish generalizable pointwise spatial relationship between structure and function through occlusion analysis of a deep-learning (DL) model for predicting the visual field (VF) sensitivities from 3-dimensional (3D) OCT scan.

DESIGN: Retrospective cross-sectional study.

PARTICIPANTS: A total of 2151 eyes from 1129 patients.

METHODS: A DL model was trained to predict 52 VF sensitivities of 24-2 standard automated perimetry from 3D spectral-domain OCT images of the optic nerve head (ONH) with 12 915 OCT-VF pairs. Using occlusion analysis, the contribution of each individual cube covering a 240 × 240 × 31.25 μm region of the ONH to the model's …

Ic3d Classification Of Corneal Dystrophies-Edition 3, Jayne Weiss, Christopher Rapuano, Berthold Seitz, Massimo Busin, Tero Kivelä, Nacim Bouheraoua, Cecilie Bredrup, Ken Nischal, Harshvardhan Chawla, Vincent Borderie, Kenneth Kenyon, Eung Kweon Kim, Hans Ulrik Møller, Francis Munier, Tim Berger, Walter Lisch

Wills Eye Hospital Papers

PURPOSE: The International Committee for the Classification of Corneal Dystrophies (IC3D) was created in 2005 to develop a new classification system integrating current information on phenotype, histopathology, and genetic analysis. This update is the third edition of the IC3D nomenclature.

METHODS: Peer-reviewed publications from 2014 to 2023 were evaluated. The new information was used to update the anatomic classification and each of the 22 standardized templates including the level of evidence for being a corneal dystrophy [from category 1 (most evidence) to category 4 (least evidence)].

RESULTS: Epithelial recurrent erosion dystrophies now include epithelial recurrent erosion dystrophy, category 1 ( …

Combined Ion Beam Irradiation Platform And 3d Fluorescence Microscope For Cellular Cancer Research, Andrew D Harken, Naresh T Deoli, Citlali Perez Campos, Brian Ponnaiya, Guy Garty, Grace S Lee, Malte J Casper, Shikhar Dhingra, Wenze Li, Gary W Johnson, Sally A Amundson, Peter W Grabham, Elizabeth M C Hillman, David J Brenner

Faculty, Staff and Student Publications

To improve particle radiotherapy, we need a better understanding of the biology of radiation effects, particularly in heavy ion radiation therapy, where global responses are observed despite energy deposition in only a subset of cells. Here, we integrated a high-speed swept confocally-aligned planar excitation (SCAPE) microscope into a focused ion beam irradiation platform to allow real-time 3D structural and functional imaging of living biological samples during and after irradiation. We demonstrate dynamic imaging of the acute effects of irradiation on 3D cultures of U87 human glioblastoma cells, revealing characteristic changes in cellular movement and intracellular calcium signaling following ionizing irradiation.

Lamina Cribrosa Insertions Into The Sclera Are Sparser, Narrower, And More Slanted In The Anterior Lamina, Fengting Ji, Mohammad R. Islam, Bingrui Wang, Yi Hua, Ian A. Sigal

Mechanical Engineering Faculty Publications

Purpose: The lamina cribrosa (LC) depends on the sclera for support. The support must be provided through the LC insertions. Although a continuous insertion over the whole LC periphery is often assumed, LC insertions are actually discrete locations where LC collagenous beams meet the sclera. We hypothesized that LC insertions vary in number, size, and shape by quadrant and depth.

Methods: Coronal cryosections through the full LCs from six healthy monkey eyes were imaged using instant polarized light microscopy. The images were registered into a stack, on which we manually marked LC insertion outlines, nothing their position in-depth and quadrant …

Novel Methods Of Identifying Individual And Neighborhood Risk Factors For Loss To Follow-Up After Ophthalmic Screening, Noah Heilenbach, Titilola Ogunsola, Ceyhun Elgin, Dustin Fry, Mina Iskander, Yara Abazah, Ahmed Aboseria, Rahm Alshamah, Jad Alshamah, Gladys Maestre

School of Medicine Publications

Précis

Residence in a middle-class neighborhood correlated with lower follow-up compared to residence in more affluent neighborhoods. The most common explanations for not following up were the process of making an appointment and lack of symptoms.

Purpose:

To explore which individual and neighborhood-level factors influence follow-up as recommended after positive ophthalmic and primary care screening in a vulnerable population using novel methodologies.

Participants

and Methods: From 2017 to 2018, 957 participants were screened for ophthalmic disease and cardiovascular risk factors as part of the Real-Time Mobile Teleophthalmology study. Individuals who screened positive for either ophthalmic or cardiovascular risk factors were …

Sans-Cnn: An Automated Machine Learning Technique For Spaceflight Associated Neuro-Ocular Syndrome With Astronaut Imaging Data, Sharif Amit Kamran, Khondker Fariha Hossain, Joshua Ong, Nasif Zaman, Ethan Waisberg, Phani Paladugu, Andrew Lee, Alireza Tavakkoli

SKMC Student Presentations and Publications

Spaceflight associated neuro-ocular syndrome (SANS) is one of the largest physiologic barriers to spaceflight and requires evaluation and mitigation for future planetary missions. As the spaceflight environment is a clinically limited environment, the purpose of this research is to provide automated, early detection and prognosis of SANS with a machine learning model trained and validated on astronaut SANS optical coherence tomography (OCT) images. In this study, we present a lightweight convolutional neural network (CNN) incorporating an EfficientNet encoder for detecting SANS from OCT images titled "SANS-CNN." We used 6303 OCT B-scan images for training/validation (80%/20% split) and 945 for testing …

The Role Of Long Noncoding Rnas In Ocular Angiogenesis And Vascular Oculopathy, Pranali Gandhi, Yuzhi Wang, Guigang Li, Shusheng Wang

School of Medicine Faculty Publications

Background: Long noncoding RNAs (lncRNAs) are RNA transcripts over 200 nucleotides in length that do not code for proteins. Initially considered a genomic mystery, an increasing number of lncRNAs have been shown to have vital roles in physiological and pathological conditions by regulating gene expression through diverse mechanisms depending on their subcellular localization. Dysregulated angiogenesis is responsible for various vascular oculopathies, including diabetic retinopathy, retinopathy of prematurity, age-related macular degeneration, and corneal neovascularization. While anti-VEGF treatment is available, it is not curative, and long-term outcomes are suboptimal, and some patients are unresponsive. Results and summary: To better understand these diseases, …

Visual Outcome And Ocular Complications In Patients With Lacrimal Gland Carcinoma After Eye-Sparing Surgery And Adjuvant Radiation Therapy, Zhenyang Zhao, Steven Jay Frank, Jing Ning, Jiawei Zhao, Xinyang Jiang, Xin A Wang, Amy C Schefler, Ehab Hanna, Amy Moreno, Brandon Gunn, Renata Ferrarotto, Bita Esmaeli

Faculty, Staff and Student Publications

Background: We report visual outcomes and ocular complications in patients with lacrimal gland carcinoma who had eye-sparing surgery followed by radiotherapy.

Methods: This review included consecutive patients with lacrimal gland carcinoma who underwent eye-sparing surgery and adjuvant radiotherapy or concurrent chemoradiation therapy between 2007 and 2018. Clinical data, including details of ophthalmological examinations and radiation treatment were reviewed.

Results: The study included 23 patients, 15 males and 8 females, with median age 51 years. Twenty patients (87%) received intensity-modulated proton therapy; 3 (13%) received intensity-modulated radiotherapy. Nineteen patients (83%) received concurrent chemotherapy. After a median follow-up time of 37 months …

Strabismus Management In Retinoblastoma Survivors, Babak Masoomian, Carol L. Shields, Hamid Riazi Esfahani, Atefeh Khalili, Fariba Ghassemi, Pukhraj Rishi, Mohammad Reza Akbari, Masoud Khorrami-Nejad

Wills Eye Hospital Papers

PURPOSE: To report the result of strabismus surgery in eye-salvaged retinoblastoma (Rb) patients.

METHODS: A retrospective case series including 18 patients with Rb and strabismus who underwent strabismus surgery after completing tumor treatment by a single pediatric ophthalmologist.

RESULTS: A total of 18 patients (10 females and 8 males) were included with a mean age of 13.3 ± 3.0 (range, 2-39) months at the time tumor presentation and 6.0 ± 1.5 (range, 4-9) years at the time of strabismus surgery. Ten (56%) patients had unilateral and 8(44%) had bilateral involvement and the most common worse eye tumor's group was D …

Novel Lipid Mediator 7s,14r-Docosahexaenoic Acid: Biogenesis And Harnessing Mesenchymal Stem Cells To Ameliorate Diabetic Mellitus And Retinal Pericyte Loss, Yan Lu, Haibin Tian, Hongying Peng, Quansheng Wang, Bruce A. Bunnell, Nicolas G. Bazan, Song Hong

School of Medicine Faculty Publications

Introduction: Stem cells can be used to treat diabetic mellitus and complications. ω3-docosahexaenoic acid (DHA) derived lipid mediators are inflammation-resolving and protective. This study found novel DHA-derived 7S,14R-dihydroxy-4Z,8E,10Z,12E,16Z,19Z-docosahexaenoic acid (7S,14R-diHDHA), a maresin-1 stereoisomer biosynthesized by leukocytes and related enzymes. Moreover, 7S,14R-diHDHA can enhance mesenchymal stem cell (MSC) functions in the amelioration of diabetic mellitus and retinal pericyte loss in diabetic db/db mice. Methods: MSCs treated with 7S,14R-diHDHA were delivered into db/db mice i.v. every 5 days for 35 days. Results: Blood glucose levels in diabetic mice were lowered by 7S,14R-diHDHA-treated MSCs compared to control and untreated MSC groups, accompanied by …

Contemporary Approach To Narrow Angles, Wesam Shamseldin Shalaby, Rohit Reddy, Reza Razeghinejad, L. Jay Katz

Wills Eye Hospital Papers

Glaucoma is the leading cause of irreversible blindness worldwide. Among all glaucoma types, primary angle closure glaucoma (PACG) affects approximately 23 million people worldwide, and is responsible for 50% of glaucoma-related blindness, highlighting the devastating consequences of this disease. The main mechanism of PACG is relative pupillary block. High-risk populations are female gender, Asian ethnicity, high hyperopia, short axial length, and a thick/anteriorly positioned lens. This review discusses the clinical diagnosis, classification, and management of patients with a narrow angle with and without intraocular pressure (IOP) elevation and glaucomatous optic nerve damage, including laser peripheral iridotomy (LPI), endocycloplasty (ECPL), lens …

Unraveling The Intraday Variations In The Tear Fluid Proteome, Garrett Jones, Jeremy Altman, Saleh Ahmed, Tae Jin Lee, Wenbo Zhi, Shruti Sharma, Ashok Sharma

Faculty, Staff and Student Publications

PURPOSE: Tear fluid is a complex and dynamic biological fluid that plays essential roles in maintaining ocular homeostasis and protecting against the external environment. Owing to the small sample volume, studying the tear proteome is challenging. However, advances in high-resolution mass spectrometry have expanded tear proteome profiling, revealing >500 unique proteins. Tears are emerging as a noninvasive source of biomarkers for both ocular and systemic diseases; nevertheless, intraday variability of proteins in tear fluid remains questionable. This study investigates intraday variations in the tear fluid proteome to identify stable proteins that could act as candidate biomarkers.

METHODS: Tear samples from …

High Clinical Exome Sequencing Diagnostic Rates And Novel Phenotypic Expansions For Nonisolated Microphthalmia, Anophthalmia, And Coloboma, Bhavana Kunisetty, Bailey A Martin-Giacalone, Xiaonan Zhao, Pamela N Luna, Brian P Brooks, Robert B Hufnagel, Chad A Shaw, Jill A Rosenfeld, A J Agopian, Philip J Lupo, Daryl A Scott

Faculty, Staff and Student Publications

PURPOSE: A molecular diagnosis is only made in a subset of individuals with nonisolated microphthalmia, anophthalmia, and coloboma (MAC). This may be due to underutilization of clinical (whole) exome sequencing (cES) and an incomplete understanding of the genes that cause MAC. The purpose of this study is to determine the efficacy of cES in cases of nonisolated MAC and to identify new MAC phenotypic expansions.

METHODS: We determined the efficacy of cES in 189 individuals with nonisolated MAC. We then used cES data, a validated machine learning algorithm, and previously published expression data, case reports, and animal models to determine …

Enhancing Patient Understanding: The Impact Of Educational Videos On Ophthalmology Visits, Anna Zhao

Medical Student Research Symposium

A major component of effective patient-centered care is the patient’s understanding of their health condition and treatments. Increased knowledge of medical conditions can positively modify health behaviors, such as more participation in cancer screening and better adherence to medications. However, the readability of educational materials often does not match the patients’ reading abilities. Instead, educational videos, which have gained prominence with the emergence of tele-visits following COVID-19, have shown promise in being beneficial to patients with lower literacy levels. For ocular pathologies, early identification and care are key in preventing vision loss. Tele-education in ophthalmology could increase patient awareness of …

Systolic Hypertension As Side Effect Of Topical Low Dose Atropine Drops, Barry Wasserman, Erik Massenzio, Karen Lee, David Plager

Wills Eye Hospital Papers

PURPOSE: To present a case of increased systemic hypertension and pupil dilation related to low dose atropine eyedrops.

OBSERVATIONS: A thirteen-year-old male with progressive myopia received atropine 0.05% ophthalmic drops to slow down myopia progression. He exhibited systemic systolic hypertension, photophobia, and bilateral nonreactive mydriasis. The atropine drops were discontinued, and his blood pressure and pupillary function normalized.

CONCLUSIONS AND IMPORTANCE: This case demonstrates sensitivity to low dose atropine with increased systemic blood pressure and pupillary dilation.

Risk Of Alzheimer's Disease And Related Dementias In Persons With Glaucoma: A National Cohort Study, Casey Crump, Jan Sundquist, Weiva Sieh, Kristina Sundquist

Faculty, Staff and Student Publications

PURPOSE: Glaucoma is a heterogeneous group of optic neuropathies that potentially may be associated with other cerebral neurodegenerative processes leading to dementia. However, prior studies have been inconsistent. We examined dementia risks after glaucoma diagnosis in a large population-based cohort.

DESIGN: National matched cohort study.

PARTICIPANTS: A total of 324 730 persons diagnosed with glaucoma during 1995-2017 in Sweden and 3 247 300 age- and sex-matched population-based controls without prior dementia.

METHODS: Cox regression was used to compute hazard ratios (HRs) for Alzheimer's disease (AD), vascular dementia (VaD), and all-cause dementia in persons with glaucoma compared with controls, adjusting for …

Bactericidal Efficacy Of The Combination Of Maresin-Like Proresolving Mediators And Carbenicillin Action On Biofilm-Forming Burn Trauma Infection-Related Bacteria, Anbu Mozhi Thamizhchelvan, Abdul Razak Masoud, Shanchun Su, Yan Lu, Hongying Peng, Yuichi Kobayashi, Yu Wang, Nathan K. Archer, Song Hong

School of Medicine Faculty Publications

Biofilm-associated bacterial infections are the major reason for treatment failure in many diseases including burn trauma infections. Uncontrolled inflammation induced by bacteria leads to materiality, tissue damage, and chronic diseases. Specialized proresolving mediators (SPMs), including maresin-like lipid mediators (MarLs), are enzymatically biosynthesized from omega-3 essential long-chain polyunsaturated fatty acids, especially docosahexaenoic acid (DHA), by macrophages and other leukocytes. SPMs exhibit strong inflammation-resolving activities, especially inflammation provoked by bacterial infection. In this study, we explored the potential direct inhibitory activities of three MarLs on Gram-positive (Staphylococcus aureus) and Gram-negative (Pseudomonas aeruginosa and Escherichia coli) bacteria in their biofilms that are leading …

The Optimization Of A Natural Language Processing Approach For The Automatic Detection Of Alzheimer’S Disease Using Gpt Embeddings, Benjamin S. Runde, Ajit Alapati, Nicolas G. Bazan

School of Medicine Faculty Publications

The development of noninvasive and cost-effective methods of detecting Alzheimer’s disease (AD) is essential for its early prevention and mitigation. We optimize the detection of AD using natural language processing (NLP) of spontaneous speech through the use of audio enhancement techniques and novel transcription methodologies. Specifically, we utilized Boll Spectral Subtraction to improve audio fidelity and created transcriptions using state-of-the-art AI services—locally-based Wav2Vec and Whisper, alongside cloud-based IBM Cloud and Rev AI—evaluating their performance against traditional manual transcription methods. Support Vector Machine (SVM) classifiers were then trained and tested using GPT-based embeddings of transcriptions. Our findings revealed that AI-based transcriptions …

Orbital And Periocular Complications In Patients With Sinonasal Tumours With Orbital Invasion, Jiawei Zhao, Xinyang Jiang, Ehab Hanna, Shirley Y Su, Amy Moreno, Brandon Gunn, Steven Jay Frank, Renata Ferrarotto, Jing Ning, Bita Esmaeli

Faculty, Staff and Student Publications

Aims: The purpose of this study was to determine the frequency and associated risk factors of orbital/periocular complications in patients with sinonasal tumour with orbital invasion managed with eye-sparing treatments.

Methods: A retrospective case series of patients with primary sinonasal tumour with orbital invasion from January 2008 to December 2018. Patient factors were compared between the following groups: (1)patients with orbital/periocular complications versus those who did not and (2) patients who needed secondary oculoplastic surgical procedures versus those who did not.

Results: Out of 80 patients, 48 had eye-sparing surgery, 8 had orbital exenteration and 24 were managed non-surgically. The …

Collagen Type Xii Is Undetectable In Keratoconus Bowman’S Layer, Mohammed Rigi, Hyeck-Soo Son, Loren Moon, Mario Matthaei, Divya Srikumaran, Albert S Jun, Charles G Eberhart, Uri S Soiberman

Faculty, Staff and Student Publications

PURPOSE: Corneal biomechanical failure is the hallmark of keratoconus (KC); however, the cause of this failure remains elusive. Collagen type XII (

METHODS: TaqMan quantitative PCR was performed on 31 corneal epithelium samples of progressive KC and myopic control eyes. Tissue microarrays were constructed using full-thickness corneas from 61 KC cases during keratoplasty and 18 non-KC autopsy eyes and stained with an antibody specific to COL12A1. Additionally,

RESULTS: COL12A1 expression was reduced at transcript levels in KC epithelium compared to controls (ratio: 0.58, p<0.03). Immunohistochemical studies demonstrated that COL12A1 protein expression in BL was undetectable, with reduced expression in KC epithelium, basement membrane, and stroma.

CONCLUSIONS: The apparent absence of COL12A1 in KC BL, together with the functional importance that