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The surgical reconstruction of severe corneal ulcers is a common and crucial component of the clinical practice of veterinary ophthalmology. Numerous surgical techniques are used in dogs for corneal reconstruction, and these techniques may be categorized by the material used to repair the corneal lesion. The first part of the present review described procedures that utilize autogenous ocular tissues, homologous donor tissues, and heterologous donor tissues. In this second part of the review, the categories of biomaterials and keratoprosthetics will be summarized. Biomaterials that are reported for use in dogs include amniotic membrane, porcine urinary bladder acellular matrix, porcine small intestinal submucosa, acellular porcine corneal stroma, and other miscellaneous soft tissue and cartilage grafts (e.g., preserved equine renal capsule, autologous omentum, autologous buccal mucosa membrane, bovine pericardium, and homologous peritoneum). Descriptions of keratoprosthesis surgery in dogs are currently limited, but the use of artificial corneal transplants hold promise for dogs with severe, vision‐compromising corneal disease that is not amenable to other reconstruction techniques. This review describes the results of experimental studies evaluating these graft materials in dogs, and it will summarize the findings and outcomes of the clinical articles published in each material category. Reporting inconsistencies and areas where additional research is required will be highlighted to help guide future studies in this area. A major aim of this review is to help identify potential subjects that could be evaluated in future investigations and that might lead to refinements in clinical practice. [ABSTRACT FROM AUTHOR]

The surgical reconstruction of severe corneal disease is a common and crucial component of the clinical practice of veterinary ophthalmology. The first part of the present review described procedures that utilize autogenous ocular tissues, homologous donor tissues, and heterologous donor tissues in dogs, while the second part reviewed the use of biomaterials and keratoprosthetics in this species. This third part is dedicated to the review of the use of corneal sutures including suture type and suture pattern in corneal reconstruction of small animals including dogs and cats. The review also focused on the way studies report postoperative ocular discomfort/pain and how this is treated. Lastly, the author briefly presents the simple but effective techniques available to bury corneal knots for corneal reconstructive surgery in small animal patients, such as the “tugging” and “deep‐superficial‐superficial‐deep” methods for simple interrupted sutures, and the adaptation of the latter for simple continuous sutures. [ABSTRACT FROM AUTHOR]

Simple Summary: Three-dimensional printing technology is a method of creating a three-dimensional object layer by layer using a computer-generated design. This method has enabled the production of custom models of organs or organ parts, leading to the emergence of "personalized medicine". The materials used in 3D printing include plastic, metal, and polymers. This review discusses the current state and future prospects of six biomaterials used in veterinary medicine and ophthalmology. Polycaprolactone is suitable for replacing hard tissue defects and is well tolerated in the eye, making it useful for ocular drug delivery devices. Pluronic is used for bone tissue engineering applications and could also be employed for drug delivery in ophthalmology. Silk is used for composite osteogenic scaffolds and vascular grafts, and it may be tested for creating protective lenses for the eye. Collagen is used to produce bioengineered corneas to improve the treatment of corneal ulcers. Alginate is used in cardiac and orthopedic procedures and is also employed in various ocular delivery systems for corneal repair. Hyaluronic acid is commonly used as a lubricant and can serve as a regenerative scaffold during the corneal healing process. In recent years, there has been a growing interest in 3D printing technology within the field of bioengineering. This technology offers the ability to create devices with intricate macro- and micro-geometries, as well as specific models. It has particularly gained attention for its potential in personalized medicine, allowing for the production of organ or tissue models tailored to individual patient needs. Further, 3D printing has opened up possibilities to manufacture structures that can substitute, complement, or enhance damaged or dysfunctional organic parts. To apply 3D printing in the medical field, researchers have studied various materials known as biomaterials, each with distinct chemical and physical characteristics. These materials fall into two main categories: hard and soft materials. Each biomaterial needs to possess specific characteristics that are compatible with biological systems, ensuring long-term stability and biocompatibility. In this paper, we aim to review some of the materials used in the biomedical field, with a particular focus on those utilized in veterinary medicine and ophthalmology. We will discuss the significant findings from recent scientific research, focusing on the biocompatibility, structure, applicability, and in vitro and in vivo biological characteristics of two hard and four soft materials. Additionally, we will present the current state and prospects of veterinary ophthalmology. [ABSTRACT FROM AUTHOR]

Despite access to contemporary phacoemulsification technology and the strong shift to two‐handed nucleofractis techniques in human medicine, a one‐handed, single incision approach has persisted among Diplomates of the American College of Veterinary Ophthalmologists. The perpetuation of techniques such as bowl‐sculpting one‐handed phacoemulsification in veterinary medicine is multifactorial; it is likely associated with the lack of two‐handed training in residency programs, the challenges of learning on complex cases, the ease of teaching one‐handed versus two‐handed techniques to a resident, and the lack of specific instrumentation available designed for larger lens size, among other factors. Additionally, variation in globe and palpebral fissure size in veterinary patients complicates the training of cataract surgery. Finally, many mentors or mentors' mentors, were trained alongside previous generations of MD surgeons who performed bowl sculpting techniques during the transition from extracapsular cataract extraction to phacoemulsification, and understandably, are not comfortable teaching a two‐handed technique consistently. The authors have observed an unwillingness to convert from one‐handed to two‐handed technique in the post‐residency career for most veterinary ophthalmologists; this could be due to the high expectations becoming a specialist, especially when the stakes are as high as in phacoemulsification. Therefore, the authors advocate for hands‐on training in multiple nucleofractis techniques, including two‐handed methods during residency training. Simply put, if residents are not trained and comfortable with two‐handed techniques by the end of residency, they are less likely to make further changes later in their career. In this article, we aim to explore the proposed rates of one‐handed versus two‐handed mentors currently teaching veterinary phacoemulsification, the history of cataract surgery, and to discuss the benefits of two‐handed nucleofractis techniques. The authors will also illustrate and provide videos as well as some tools for veterinary ophthalmologists wishing to learn two‐handed techniques. [ABSTRACT FROM AUTHOR]

Brachycephaly in cats, characterized by shortened facial and skull length and a rounder head due to inherited defects in skull bone development, can lead to respiratory and ocular problems, particularly in popular breeds like Exotic Shorthair, British Shorthair, Persian and Scottish Fold. Eye diseases in cats and dogs can result from various factors, including infectious agents, metabolic disorders, physical trauma and breed-specific congenital abnormalities, with brachycephalic cats being particularly prone to chronic corneal diseases and glaucoma due to their anatomical features. Despite challenges such as cost, the need for anesthesia and radiation exposure, understanding normal eye measurements and biometrics through imaging techniques like ultrasound, MRI and CT is essential for diagnosing eye diseases in veterinary ophthalmology. This study aimed to utilize computed Tomography (CT) images to measure intraocular structures in healthy cats with varying skull structures and establish the correlation between these measurements and skull morphometric data. In the study, a total of 24 cats from brachycephalic and 27 cats from non-brachycephalic breeds (both sexes) were included. Two- dimensional CT scans of cats were reconstructed into 3D models using the 3D Slicer 5.4.0 program, which was also used for intraocular and skull measurements. Results demonstrated that the anterio-posterior distance of the lens and postorbital breadth measurements were higher, while greatest length of the skull was lower, in brachycephalic than in non-brachycephalic cats (p<0.05). According to the results of Discriminant Function analysis, when considering head types, it was observed that 92.6% of animals with non-brachycephalic head and 79.2% of animals with brachycephalic head types were accurately classified. These findings emphasize the importance of considering anatomical variations in brachycephalic and non-brachycephalic cats for accurate diagnosis of eye health issues in these cats. [ABSTRACT FROM AUTHOR]

Monogenean ectoparasitic flatworm infestations, particularly in closely confined populations, can result in severe epizootic disease that is often devastating and occasionally fatal. This case series describes a population of cownose rays (Rhinoptera bonasus) (n = 52) housed in an aquarium touchtank exhibit that presented with severe ocular disease due to infestation with monogeneans, presumably Benedeniella posterocolpa of the Capsilidae family. The most severely affected individuals (n = 9), including several cases with bilaterally ruptured corneas, underwent serial examinations prior to and following treatment with praziquantel, systemic antibiotics, and corticosteroids. The entire population underwent frequent therapeutic water changes with a scheduled decrease in salinity, increase in temperature, and a series of seven praziquantel tank treatments. At the last follow up examination (3.75 years), the most common ocular findings were corneal fibrosis (18/18 eyes; 100%), cataract formation (13/18 eyes; 72.2%), synechia (8/18 eyes; 44.4%), and dyscoria (5/18 eyes; 27.8%). Despite severe corneal disease, including corneal rupture, all examined eyes (18/18; 100%) showed remarkable corneal remodeling and a largely clear visual axis. There are very few reports describing corneal disease in aquarium housed elasmobranchs, and no reports describe ophthalmic implications of monogenean infestation in these animals. This further underscores the importance of this case series in demonstrating the capacity for healing of elasmobranch eyes and can provide further guidance regarding prognosis and treatment in cases of severe corneal disease. [ABSTRACT FROM AUTHOR]

In the current context of emerging and spreading antimicrobial resistance in human and animal infections, new strategies need to be developed to improve the efficacy of commonly prescribed antibiotics and preserve more critical compounds for multi-drug-resistant infections. This preliminary study aimed at evaluating the benefits of an eye cleaning solution containing 0.1% EDTA, 0.02% Tris, and 0.1% Polysorbate 80 in veterinary ophthalmology. A first in vitro study was performed to assess the bactericidal activity of the test solution against Staphylococcus aureus and Pseudomonas aeruginosa strains. A second in vitro study evaluated the impact of the test solution on the antimicrobial activity of neomycin against Staphylococcus aureus. The test solution alone did not show bactericidal activity against Staphylococcus aureus and Pseudomonas aeruginosa. The test solution seemed to increase the activity of Neomycin Sulfate against Staphylococcus aureus. These findings warrant further research to better characterize the impact on the bactericidal activity of antimicrobials used in veterinary ocular surface infections of the solution containing 0.1% EDTA, 0.02% Tris, and 0.1% Polysorbate 80 as well as of each individual ingredient for a thorough understanding of how this test solution could provide a new strategy to address the growing antimicrobial resistance issue worldwide. [ABSTRACT FROM AUTHOR]

Understanding the specifics of the orbit of each species is a fundamental and crucial step in the development of veterinary ophthalmology. This article describes the bone structure, foramina piercing the bones, and shape of the orbit in the European beaver (Castor fiber). Additionally, a morphometric analysis of the orbit was conducted, measuring its height, width, and depth, and the orbital index was calculated. A total of 27 skulls of this species were used for the study. The average length and depth of the orbit were shown to be greater in females, while the average width was comparable in both sexes. Males, however, had a higher average orbital index. These differences, assessed with a t-test, were shown to be statistically significant. These results are the first step towards developing reference values for the European beaver for the dimensions determined in this study. [ABSTRACT FROM AUTHOR]

Objective Animals studied and procedures Results Conclusions The aim of the study was to investigate clinical features of lamellar keratectomy for presumed calcific corneal degeneration in a population of geriatric dogs using blunt scissors dissection under topical anesthesia.Retrospective analysis of dogs with clinically diagnosed calcific degeneration treated by keratectomy under topical anesthesia between 2015 and 2021 at two veterinary ophthalmology practices was performed. Descriptive data regarding signalment, concurrent systemic and ocular disease, complications, healing time, and recurrence were collected. Kaplan–Meier survival analysis was performed to calculate 1‐year recurrence probability.Sixty‐five eyes in 57 dogs met inclusion criteria. All 54 eyes with follow‐up healed within a median of 14 days (7–74), including 17 with complicating factors of infection or deep stromal ulceration. Globe rupture occurred intraoperatively in three eyes (4.6%), for which subsequent conjunctival graft was performed. Calculated 1‐year recurrence probability from 47 eyes followed long term was 25%. Multivariate Cox proportional hazard modeling showed a significant association between documented systemic disease and time to recurrence (p = .035), irrespective of topical EDTA use (p = .432). Median follow‐up time available for all cases was 249 days.Blunt lamellar dissection with corneal scissors can be performed in dogs under topical anesthesia, yielding healing times and recurrence comparable to previously reported treatments for calcific corneal degeneration. Globe rupture is an inherent risk of both the disease and procedure and occurred in 4.6% of treated eyes. This approach expands non‐anesthetic treatment options for affected patients but should only be performed with advanced microsurgical training and client counseling on individual risk and benefit. [ABSTRACT FROM AUTHOR]

A 9‐year‐old, female spayed domestic short‐haired cat was presented with a 4‐year history of bilateral lipogranulomatous conjunctivitis (LGC), which was confirmed via histopathology. Thirteen months following the initial biopsy, the cat was presented with a rapidly progressive mass lesion of the palpebral conjunctiva of the right eye. A surgical debulking, followed 1 month later by exenteration after marked regrowth of the mass confirmed fibrosarcoma. This case report is the first to describe a cat with chronic bilateral LGC that later developed a unilateral fibrosarcoma within the eyelid tissue of the right eye. Fibrosarcoma should be considered a differential in any cat with chronic LGC that develops a rapidly progressive mass in the eyelid. [ABSTRACT FROM AUTHOR]

This document is a collection of abstracts from the 11th Asian Veterinary Ophthalmology Annual Conference held in Taipei City, Taiwan in October 2023. The abstracts cover various topics related to veterinary ophthalmology, including case reports and research studies. Some of the topics discussed include the use of modified rhytidectomy for entropion in Shar Pei dogs, the use of hyaluronic acid injection for entropion treatment, the effects of intracameral tissue plasminogen activator injection on intraocular pressure control after cataract surgery, the application of corneal bandage lens for deep corneal ulceration treatment in cats, and the evaluation of retina and optic nerve head in cats with mild intraocular pressure elevation using optical coherence tomography. These abstracts provide valuable insights into the field of veterinary ophthalmology and can be useful for researchers and practitioners in this area. [Extracted from the article]

Copyright of Arquivos de Ciências Veterinárias e Zoologia da Unipar is the property of Associacao Paranaense de Ensino e Cultura and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Monogenean ectoparasitic flatworm infestations, particularly in closely confined populations, can result in severe epizootic disease that is often devastating and occasionally fatal. This case series describes a population of cownose rays (Rhinoptera bonasus) (n = 52) housed in an aquarium touch-tank exhibit that presented with severe ocular disease due to infestation with monogeneans, presumably Benedeniella posterocolpa of the Capsilidae family. The most severely affected individuals (n = 9), including several cases with bilaterally ruptured corneas, underwent serial examinations prior to and following treatment with praziquantel, systemic antibiotics, and corticosteroids. The entire population underwent frequent therapeutic water changes with a scheduled decrease in salinity, increase in temperature, and a series of seven praziquantel tank treatments. At the last follow up examination (3.75 years), the most common ocular findings were corneal fibrosis (18/18 eyes; 100%), cataract formation (13/18 eyes; 72.2%), synechia (8/18 eyes; 44.4%), and dyscoria (5/18 eyes; 27.8%). Despite severe corneal disease, including corneal rupture, all examined eyes (18/18; 100%) showed remarkable corneal remodeling and a largely clear visual axis. There are very few reports describing corneal disease in aquarium housed elasmobranchs, and no reports describe ophthalmic implications of monogenean infestation in these animals. This further underscores the importance of this case series in demonstrating the capacity for healing of elasmobranch eyes and can provide further guidance regarding prognosis and treatment in cases of severe corneal disease.

Objective: Assess the accuracy of abstracts in published veterinary ophthalmology articles. Procedures: Abstracts and contents of 204 original research articles in veterinary ophthalmology published in seven peer‐reviewed journals between 2016–2020 were reviewed. Abstracts were considered inconsistent if they contained data that were either missing from or inconsistent with corresponding data in the article's body. Each abstract was graded between 0 (inaccurate) to 3 (accurate), and each inconsistency was subjectively classified as minor or major. The influence of selected variables was assessed: journal, impact factor, year of publication, number of words in abstract, study type (prospective/retrospective), and characteristics of the corresponding author [institution (academia/private practice), country of domicile (native/non‐native English), number of publications]. Results: Most abstracts were accurate, with 1%, 4%, 9% and 86% receiving a score of 0, 1, 2 and 3, respectively. When detected, most inconsistencies were considered minor (77%). Although not statistically significant (p ≥.130), the proportion of articles with a perfect score (=3) was higher in prospective (88%) vs. retrospective (81%) studies, academia (88%) vs. private practice (78%), and studies from corresponding authors domiciled in English (89%) vs. non‐English (83%) speaking countries. A significant but very weak (r = −0.15 to −0.19; p ≤.034) negative correlation was found between accuracy score and number of words, as well as 1‐year and 5‐year impact factors. Conclusions: Although relatively uncommon, data in abstracts that are inconsistent or missing from the article's body do occur in veterinary ophthalmology articles, and could adversely influence a reader's interpretation of study findings. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to bibliometrically analyze the 100 most‐cited articles published in the Veterinary Ophthalmology (VO) journal. Methods: Web of Science was searched for citations of VO articles published in 1998–2022. Tissue and species studied, and first and last author domicile and affiliation were recorded for the 100 most‐cited articles and descriptively analyzed. Results: Altogether, the 100 most‐cited VO articles have cited a total of 5483 times. Most commonly, these were devoted to the cornea (23%), multiple tissues (19%), and glaucoma (16%). Studies on dogs (36%), horses (17%), and multiple species (15%) were most often cited. Most first/last authors were from the USA (n = 113), Brazil (n = 13), and France and Germany (n = 7 each), and most frequently affiliated with the University of Florida (n = 36), University of Wisconsin‐Madison (n = 15), and Animal Health Trust, North Carolina State University, and Ohio State University (n = 6 each). KN Gelatt (n = 9), DE Brooks (n = 6), and FJ Ollivier and EO MacKay (n = 5 each) were the most frequent first or last authors. The greatest number of citations was for articles with KN Gelatt (n = 555), FJ Ollivier (n = 411), and DE Brooks (n = 372) as first or last authors. "The comparative morphology of the tapetum lucidum" by FJ Ollivier et al. (2002) is the most frequently cited article in VO history (n = 178). Conclusions: This study provides insight into the impact of publishing in VO and a more comprehensive understanding of trends and the most influential contributions to VO. [ABSTRACT FROM AUTHOR]

Background: Cat scratches and ocular foreign bodies are frequent reasons for consultation in veterinary ophthalmology. Case Description: We here present an unusual case combining trauma to the cornea and lens by a cat scratch with retention of the claw in the anterior chamber. Management consisted of the removal of the claw, reconstruction of the cornea, and mechanized ablation of the lens by phacoemulsification with implantation of an artificial lens. Conclusion: The progression during the follow-up period was considered satisfactory, with positive responses to visual tests and intraocular pressure within the norms. Only dyscoria and a tear of the endothelium and Descemet membrane, secondary to the trauma, remained. [ABSTRACT FROM AUTHOR]

A 6‐year‐old miniature Shetland pony mare was referred for evaluation of a left corneal mass, which developed from the healing tissue of a corneal traumatic ulceration that had occurred 4 weeks previously. On gross examination, a spherical, smooth‐surfaced, and pink‐colored lesion of about 1 cm in diameter was protruding from the left palpebral fissure. Ophthalmic examination revealed that it was attached to the scar tissue of the cornea, and that one corpora nigra was adherent to the posterior face of corneal wounded area, without sign of uveitis. The remainder of the ophthalmic examination was unremarkable. The mass was excised, and cryotherapy was used as an adjunctive therapy. Histopathology of the resected mass was consistent with a pyogenic granuloma on the basis of radially oriented proliferating capillaries, embedded in immature granulation tissue containing an infiltrate of neutrophils, plasma cells and eosinophils. There were no histological features of malignancy. 2 months after surgery, the ventral part of the fibrotic corneal scar was slightly raised by a pink tissue, suggesting possible recurrence of the initial lesion. A second cryotherapy was performed over the leukoma area. No recurrence has been noted for a follow‐up period of more than 25 months. Pyogenic granuloma is a benign proliferative fibrovascular response that typically develops after trauma or surgery. Corneal involvement is rare in humans, and to the authors' knowledge has never been documented in veterinary ophthalmology. [ABSTRACT FROM AUTHOR]

Injury to the cornea results in a cascade of processes that lead to the healing of the wound and restoration of vision, requiring integration of cellular proliferation, migration, differentiation, apoptosis, and intercellular communication. Combinations of growth factors and cytokines present in the tear film and cornea of the eye are involved in these processes. The presented article reviews the corneal anatomy and the most common lesions of the cornea in veterinary ophthalmology. It overviews the chemical signal-mediated events and the important role of the growth factors as regulators in healing and repairing the corneal cells and the corneal layers. [ABSTRACT FROM AUTHOR]

This case report describes ocular and nasal leech infestation (hirudiniasis) in a dog. The patient presented for a suspected ocular foreign body. The patient was sedated to allow proper examination, which revealed a leech foreign body attached to the bulbar conjunctiva adjacent to the inferotemporal limbus of the left eye. A 3.5% hypertonic saline solution was applied topically to the eye in four sequential drops, until the leech detached itself and was removed with a cotton bud. The affected eye was found to have a small corneal ulcer, a small area of scleral haemorrhage, and prominent lymphoid follicles within the third eyelid. Approximately 5 min after the leech was removed, another leech emerged from the left nostril. The patient was sent home on chloramphenicol ointment for treatment of the corneal ulcer, was rechecked 4 days later by an American Board of Veterinary Ophthalmology resident (PM) and found to have a normal ocular exam. This case report highlights that topical hypertonic saline solution (3.5%) can be an effective and easily prepared treatment for ocular and nasal hirudiniasis in veterinary patients. [ABSTRACT FROM AUTHOR]

Cyclosporine A (CsA) is a selective and reversible immunosuppressant agent that is widely used as a medication for a wide spectrum of diseases in humans such as graft versus host disease, non-infectious uveitis, rheumatoid arthritis, psoriasis, and atopic dermatitis. Furthermore, the CsA is used to treat keratoconjunctivitis sicca, chronic superficial keratitis, immune-mediated keratitis and equine recurrent uveitis in animals. The selective activity of Cyclosporine A (CsA) was demonstrated to be an immunomodulation characteristic of T-lymphocyte proliferation and inhibits cytokine gene expression. Moreover, the lipophilic characteristics with poor bioavailability and low solubility in water, besides the side effects, force the need to develop new formulations and devices that will provide adequate penetration into the anterior and posterior segments of the eye. This review aims to summarize the effectiveness and safety of cyclosporine A delivery platforms in veterinary ophthalmology. [ABSTRACT FROM AUTHOR]

Reports regarding curricula in ophthalmology across veterinary schools are not currently available. The objective of this study was therefore to investigate the number of contact hours and approaches to teaching ophthalmology in the curriculum of English-speaking veterinary schools worldwide. An online survey was distributed to 51 veterinary colleges in North America, the United Kingdom, Australia, New Zealand, and the Caribbean. Questions pertained to hours dedicated to didactic and laboratory-based instruction, species used, final-year rotations, in-person compared with online instruction, and effective and less effective approaches to teaching veterinary ophthalmology. Descriptive statistics of the quantitative survey responses and a thematic analysis of the open-ended responses were conducted, respectively. A 71% ( n = 36/51) response rate was recorded, and the average number of American or European board-certified ophthalmologist instructors per veterinary college was 2.33. Total didactic contact hours varied from 6 to 63 hours ( M = 25.6 ± 15.7 hours), and total laboratory contact hours varied from 0 to 153 hours ( M = 25.47 ± 38.17 hours), mainly occurring in the fourth year. Dogs were the most used species in surgical exercises (40%). Final-year rotations occurred in 88% of schools, and 88% of instruction was conducted in person across all schools. Case-based learning, review of basic sciences, and use of video were identified as effective didactic teaching strategies by 72% (26/36), 47% (17/36), and 31% (11/36) of schools, respectively. This report can serve as a reference for future studies guiding curricular delivery in veterinary ophthalmology.

In vivo confocal microscopy (IVCM) is a relatively new ocular imaging technique that permits morphological and quantitative assessment of the living cornea on the cellular level. The applications for IVCM in clinical ophthalmology are numerous and diverse. There are several advantages inherent to IVCM over standard diagnostic techniques currently used to confirm a diagnosis of infectious keratitis in veterinary ophthalmology. With IVCM, images can be viewed in real‐time providing immediate diagnostic information. Traumatic corneal sampling techniques are avoided, and the procedure can be repeated as frequently as is clinically indicated without risk of corneal tissue damage. Both superficial and deep corneal lesions can be evaluated by IVCM in an atraumatic fashion. Microorganism viability is not required for their detection and specialized diagnostic laboratory assay procedures are not necessary. Many larger infectious agents can be directly identified within corneal lesions by IVCM, including fungi and parasites such as Acanthamoeba spp. In other situations, such as bacterial infectious crystalline keratopathy, the biological systems associated with the microorganism can be detected within the cornea. The current resolution of IVCM is inadequate to directly visualize some corneal infectious agents, such as herpesviruses, but host responses and virus‐infected epithelial cells can be identified. This review summarizes the current knowledge and applications of IVCM in the management of infectious keratitis in veterinary ophthalmology, including its use in animals with bacterial, fungal, parasitic, and viral keratitis. [ABSTRACT FROM AUTHOR]

The usage of canine amniotic membrane (cAM) is mainly of interest in veterinary ophthalmology. Topical formulations of cAM could deliver the beneficial properties of cAM without the need for surgical intervention. The present study aimed to investigate biological compositions of cAM and its extracts, including their corneal wound healing efficacy. In this study, canine amniotic membrane extract (cAME) and lyophilized canine amniotic membrane extract (cAMX) were developed. Bioactive molecules related to corneal wound healing, including hepatocyte growth factor, tissue inhibitor of metalloproteinase-1 and -2, Thrombospondin-1 and Interleukin-1 receptor antagonist were studied at both gene and protein expression levels. Cell viability and wound healing assays were investigated for the possibility of cAME and cAMX as topical applications. The results demonstrated that all of the relevant genes and proteins were detected in cAM, cAME and cAMX. Both cAME and cAMX showed wound healing properties in vitro and cAME at 1.0 mg/mL concentration appeared to have the best healing efficacy. In conclusion, cAME and cAMX generated for topical use provided promising results in the healing of corneal defects. [ABSTRACT FROM AUTHOR]

Corneal ulcers are one of the most common ocular disorders in veterinary ophthalmology and several factors can negatively influence the efficacy of the currently available therapeutic options, leading to a loss of corneal transparency and, thus, vision. Twenty-five dogs with clinical signs of corneal ulcers were randomised to receive either corneal phototherapy (16 dogs; study group) or topical standard medical therapy (9 dogs; control group). The riboflavin/UV-A corneal phototherapy (PACK-CXL) consisted in the application of a riboflavin ophthalmic solution (Visioflavin®; Vision Engineering Italy srl, Rome, Italy) onto the cornea for 20 min followed by 30 mW/cm² UV-A irradiance for 3 min using a point-of-care UV-A device (Vetuvir®; Vision Engineering Italy srl, Rome, Italy). The complete healing of the ulcerative lesion was defined as the complete restoration of the corneal epithelial integrity with negative fluorescein staining. The corneal phototherapy achieved complete corneal healing in all the dogs by 20.5 ± 7.8 days. In the control group, only two dogs achieved complete healing by 21.5 ± 15.6 days. This intervention may represent a valid option to hasten corneal wound healing and a clinical resolution of ulcerative keratitis in dogs. [ABSTRACT FROM AUTHOR]

Background: Hemangiosarcoma is a malignant vascular tumor commonly described in veterinary ophthalmology as emerging at the margin of the third eyelid and bulbar conjunctiva. The primary corneal attachment of the tumor is considered rare, as the cornea is an avascular structure, but there are sparse reports of primary occurrences in the cornea of dogs, cats, and horses. No reports were found in wild animals. The Tapirus terrestris, commonly known as Tapir, is a perissodactyl mammal that inhabits South America regions, being considered the largest terrestrial mammal of Brazil and one of the most popular animals in zoos in various countries. This paper aims to report the first case of primary corneal hemangiosarcoma in a 25-year-old female Tapir (Tapirus terrestris) held in captivity. Case: A 25-year-old Tapirus terrestris female presented an irregular mass in the right cornea, mucopurulent secretion, and inconclusive previous cytological evaluation. It also had a history of a milky cornea for many years, and in the last 12 months, a tissue growth was observed, as well as the occurrence of mucopurulent secretion. The menace response in the right eye was negative. In the ophthalmologic examination, a red-colored, lobed, hemorrhagic, and ulcerated mass occupying approximately 90% of the cornea was observed, and in the peripheral cornea, there was an intense discoloration. Due to the extension of the mass and visual loss, the transpalpebral enucleation was performed under general inhalation anesthesia. The histopathological analysis evidenced a vascular tumor restricted to the central peripheral cornea, composed of blood vessels of small and large caliber, showing polygonal endothelial cells with moderate atypia, anisocytosis, and anisocariasis, in addition to dense stroma and inflammatory cells. The mass occupied the anterior corneal stroma, and there was no involvement of bulbar conjunctiva, sclera, or intraocular structures. The immunohistochemical study revealed the positivity of neoplastic cells for CD31, and the proliferative index of the lesion was evaluated by the Ki-67 as inferior to 10%. Discussion: The histopathologic and immunohistochemical examinations evidenced a hypercellular lesion, and the diagnosis of primary corneal hemangiosarcoma (HSA) was possible due to the significant cellular atypia identified in the lesion. To the authors' knowledge, this is the first case of corneal hemangiosarcoma described in Tapirus terrestris. The HAS is a malignant neoplasm originating in the vascular endothelial cells. There is a significant correlation between the HSA and prolonged exposure to solar radiation. The tapir of this report lived in a high-altitude region with exposure to ultraviolet rays; therefore, it might be an important predisposing factor for the HSA emergence. The chosen treatment for vascular tumors according to the visual prognostic is the lamellar keratectomy; however, the transpalpebral enucleation was the elected treatment since the eye was not visual, the neoplasm had a great extension, the animal was in advanced age and lived in captivity, and it was difficult to handle the animal without sedation to perform adjuvant therapies. Since the mass corresponded to 90% of the cornea, total removal with free edges would not be possible as described in the literature, and, therefore, there was an increased risk of relapse. In the follow-up after 3 years of surgical excision, the animal remained free of metastasis, reinforcing the diagnosis of primary corneal hemangiosarcoma. [ABSTRACT FROM AUTHOR]

Background: Ocular lymphoma can affect the iris, conjunctiva, choroid, and retina and is mostly associated with multicentric disease. Elastography is an ultrasound technique that provides noninvasive, pain-free assessment of tissue stiffness. It has the ability to assess subtle changes throughout the organ as well as focal lesions. Microbubble contrast ultrasound enables the detection of incipient vascular flows, which are difficult to detect using traditional ultrasound methods. This study aimed to describe acoustic radiation force impulse (ARFI) elastography and microbubble contrast ultrasound findings in the eyes of two dogs diagnosed with intraocular T-cell lymphoma. Cases: Case 1. Physical examination revealed an exophytic mass in the left eye. Schirmer test revealed a secretion of 22 mm/min. Negative threat reflex, glare, direct pupillary light reflex, and consensual response were also noted. Biomicroscopy revealed hyperplasia of the third eyelid, overlapping with the affected eye. When the membrane was removed, moderate conjunctival hyperemia, mucoid secretion, and buphthalmia were observed. In addition, significant corneal edema was present, making it impossible to visualize the anterior chamber and perform fundus examination. The intraocular pressure, as measured with a rebound tonometer, was 39 mmHg. B-mode ultrasonography identified amorphous, hyperechoic, and heterogeneous structures throughout the anterior chamber, iris, and ciliary body. The elastogram showed that the mass had greenish tones and intermediate stiffness, and the mean SWV of the ciliary body and iris was 2 m/s. Contrast-enhanced ultrasound (CEUS) revealed vascularization of the neoformation region, with wash-in, peak, and wash-out values of 9.89 s, 24.56 s, and 107.87 s, respectively. Case 2. On physical examination, a change in the shape of the right pupil was observed. Schirmer test revealed a secretion of 20 mm/min, with negative threat, glare, and pupillary reflexes to direct and consensual light. Biomicroscopy revealed neoformation from 7 am to 11 am in the sclera, retina, and choroid complex, concomitant with dyscoria and conjunctival hyperemia. The intraocular pressure, as measured by rebound tonometry, was 33 mmHg. Fundoscopy revealed a mass in the temporal region and focal retinal detachment. No changes were observed in the contralateral eye. B-mode ultrasound revealed an increase in volume in the temporal region of the iris, ciliary body, and choroid with diffuse heterogeneity and partial retinal detachment. Elastographic examination revealed shades of green and yellow compatible with increased tissue stiffness. On quantitative examination, the mean SWVs of the ciliary body and iris were 3.14 m/s. On CEUS, the neoformation region presented wash-in, peak, and wash-out values of 8.67 s, 22.33 s, and 80.20 s. Discussion: B-mode ultrasonography established the tumor extent and evaluated echogenicity, verifying the involved ocular structures. The examination played an important role in the diagnosis as well as clinical management. ARFI elastography can detect small tissue changes, helping to define nodules and masses more reliably, in addition to allowing the verification of tissue stiffness. In both dogs, it was possible to verify that the masses presented greater rigidity than the adjacent tissues both qualitatively and quantitatively. In previous studies, it was found that cutaneous and breast lymphomas in humans were more rigid than adjacent tissues on elastography. This increase in rigidity and heterogeneity observed on elastograms can be explained by the extramedullary interactions of the matrix in T-cell lymphomas. Tumor growth is dependent on the blood supply, which was evaluated using CEUS in these cases. Furthermore, the ciliary body contrast filling times were longer than those described in normal dogs. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the frequency of ophthalmic disorders in 7 brachycephalic dog breeds referred to an academic veterinary ophthalmology service. Animals: 970 client-owned dogs of 7 brachycephalic breeds that were evaluated by the ophthalmology service in a veterinary teaching hospital from January 2008 through December 2017. Procedures: Medical records of 7 brachycephalic breeds (ie, Boston Terriers, English Bulldogs, French Bulldogs, Lhasa Apsos, Pekingese, Pugs, and Shih Tzus) were reviewed to collect data regarding patient signalment, ophthalmic diagnoses, affected eyes, and number and dates of visits. Results: Median age at the first examination was 7 years (range, 23 days to 22 years). The number of dogs seen for a first examination increased with age. Corneal ulcers, keratoconjunctivitis sicca, corneal pigmentation, immature cataracts, and uveitis were each diagnosed in ≥ 100 dogs and represented 40.4% (1,161/2,873) of all diagnoses. On the basis of anatomic location, 66.3% (1,905/2,873) of all disorders were located in either the cornea (1,014/2,873 [35.2%]) or adnexa (891/2,873 [31%]). There was a significant difference in breed proportion in the study population; of the 7 breeds studied, Shih Tzus (34.3% [333/970]), Pugs (20.8% [202/970]), and Boston Terriers (16.6% [161/970]) were the most prevalent breeds. The frequency of some diseases within the referral population was associated with breed. Conclusions and clinical relevance: Findings suggested that the most prevalent disorders for the brachycephalic breeds in this ophthalmic referral population were corneal ulcers, keratoconjunctivitis sicca, corneal pigmentation, immature cataracts, and uveitis. Although all dogs shared brachycephalic features, the frequency of specific ophthalmic diseases varied between breeds. [ABSTRACT FROM AUTHOR]

The maned wolf, Chrysocyon brachyurus, is a near‐threatened carnivore inhabiting the Brazilian Cerrado. Few studies have been conducted on this species, and even fewer have explored its ophthalmological characteristics. Vision is critical to wild canids; thus, this study aimed to provide a morphoquantitative description of the bulbar conjunctiva of the maned wolf using cytological and histological analyses. Ten healthy maned wolves from a conservational centre, including 4 females and 6 males aged 1–12 years (6.5 ± 2.8), were included in the study. The samples for cytological analysis were collected from the inferior conjunctival sac using a cytobrush, and conjunctival tissue was collected for histological analysis from the temporal canthus zone. The cytological samples were stained using the Papanicolaou method, and the histological sections were stained using haematoxylin and eosin, Periodic acid–Schiff, picrosirius red and Masson's trichrome stains. The cytological samples were studied for stain quality, and the different cell types were counted. Histological examination was used to determine tissue types in the conjunctiva and their proportions. Analyses revealed a stratified squamous epithelium with some goblet cells and eventual pigmentation in the basal layer. Loose connective tissue with the presence of some mononuclear and polymorphonuclear cells was also observed. The epithelium of the maned wolf's bulbar conjunctiva resembles that of dogs and other carnivore species; furthermore, its physiological and pathological responses were similar to those of other carnivore species. [ABSTRACT FROM AUTHOR]

Glaucoma is a disorder of all species due to a rise of intraocular pressure (IOP) beyond which is compatible with ganglion cell and axon function, often resulting in optic nerve degeneration and irreversible blindness. Glaucoma treatment with surgical intervention aimed at either reducing aqueous production, or increasing or altering aqueous outflow has evolved over preceding decades, but there remains no cure. The present article is intended to provide a concise review of glaucoma surgical therapies in veterinary ophthalmology. [ABSTRACT FROM AUTHOR]