Veterinary ophthalmology最新文献

Introduction: Conjunctivitis is a prevalent feline ocular surface disorder, often accompanied by inflammation. Inflammatory cytokines, such as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), play a crucial role in the pathogenesis of conjunctival inflammation. This study aimed to evaluate the levels of TNF-α and IL-6 in the tears of cats with conjunctivitis and compare them with healthy controls, thereby enhancing our understanding of the inflammatory processes in feline conjunctivitis.

Methods and materials: Tear samples were collected from cats of various breeds diagnosed with conjunctivitis (n = 15) and healthy control cats (n = 5) using Schirmer strips. The levels of TNF-α and IL-6 were measured using the enzyme-linked immunosorbent assay (ELISA) method. Protein concentration were measured using Bradford assay and data were expressed as pg/mg protein of tear sample.

Results: Our results revealed a statistically significant increase in the levels of both TNF-α and IL-6 in cats with conjunctivitis compared to the control group (p < .0001). Positive correlation were observed between tear IL-6 (p < .001, r = 0.902) and TNF-α (p < .001, r = 0.919) with clinical grades of conjunctivitis.

Conclusion: The results demonstrated a significant elevation in the levels of TNF-α and IL-6 in the tears of cats with conjunctivitis, suggesting that these cytokines are involved in the inflammatory response of feline conjunctivitis. These findings could pave the way for new diagnostic and therapeutic approaches, focusing on cytokine modulation, to manage feline conjunctivitis more effectively.

Objective: To compare characteristics and treatment outcomes of spontaneous chronic corneal epithelial defects (SCCEDs) in brachycephalic non-Boxers and Boxers. We hypothesized that brachycephalic non-Boxers develop SCCEDs at a younger age and develop complications more frequently than Boxers.

Animals studied: Retrospective review of medical records of brachycephalic dogs treated for SCCEDs between January 2018 and December 2022 in multiple ophthalmology referral centers in the UK.

Procedure: Data recorded included breed, age, time of onset, treatment prior to referral, treatment at referral, time to heal, need for further procedures, and complications.

Results: A total of 464 SCCEDs in 420 dogs were included composed of 173 Boxers with 200 SCCEDs and 247 brachycephalic non-Boxer dogs with 264 SCCEDs. Boxers were significantly older (median 8.2, range 4.5-12.7 years) than brachycephalic non-Boxers (median 7.2, range 1.6-15.9 years) (p < .001). The first treatment (cotton-tipped applicator [CTA] debridement, diamond burr debridement, superficial keratectomy, grid keratotomy, punctate keratotomy, or combinations of these) selected was significantly different between groups (p < .001). Healing, excluding cases addressed by CTA debridement, following the first procedure was significantly more successful in Boxers (p = .049). Excluding cases addressed by CTA debridement, 9.6% of SCCEDs in Boxers (20/200) and 13.4% (32/239) of non-Boxers required more than one procedure. In the non-Boxer group, 9.5% (25/264) developed complications, contrasting with 4% (8/200) in the Boxer group. Non-Boxers were more likely to develop complications after the first treatment (p = .006).

Conclusion: Non-Boxer brachycephalic dogs develop SCCEDs younger than Boxers. This study suggests SCCEDs in brachycephalic non-Boxers may be less likely to heal following one mechanical treatment and are more likely to develop complications.

Purpose: To present a novel modified medial canthoplasty (MCP) technique, the application in 601 dogs (1180 eyes), and a review of the early postoperative complications related to the technique.

Introduction: Macroblepharon and nasal entropion is a common presentation in many brachycephalic dog breeds promoting chronic keratitis. The previously described MCP techniques limit the medial shortening of the eyelids to the location of the lacrimal puncta. A novel technique was developed allowing for a more extensive eyelid shortening nasally.

Methods: The modification of the here described technique includes the longitudinal splitting of the lacrimal canaliculi allowing for an extensive shortening of the lids beyond the lacrimal puncta. Records of 601 dogs which underwent the modified MCP were reviewed regarding breed, indications for surgery, follow-up, and early postoperative surgical complications. Descriptive statistics were applied.

Results: Six hundred one dogs (1180 eyes) were included in this study. Twenty-four different breeds underwent the simplified MCP with the Pug (n = 403) being the most represented breed. Indications were macropalpebral fissure, medial entropion, pigmentary keratitis, trichiasis by haired caruncle, strabismus after globe prolapse, and facial nerve paralysis. The overall complication rate was 1.01% (12/1180) and consisted of wound dehiscence 0.59% (7/1180), corneal ulceration caused by suture material 0.25% (3/1180), and wound infection (2/1180). None of the 601 operated dogs developed serious complications related to the surgical technique.

Conclusions: The simplified MCP is a novel technique with a very low complication rate.

Objective: To investigate the therapeutic effect of 275 nm wavelength ultraviolet C (UV-C) light for treatment of bacterial keratitis in canine corneas using an affordable, broadly available modified handheld device.

Methods: UV-C therapy (UVCT) was evaluated in two experiments: in vitro using triplicates of three bacterial genera (Staphylococcus, Streptococcus, Pseudomonas spp., and a mix of all species) where the UVCT was performed at a distance of 10, 15, and 20 mm with 1 or 2 doses (4 h apart) for 5, 15, or 30 s; ex vivo model where healthy canine corneal buttons were inoculated superficially and deep (330 μm) with the same bacterial isolates and treated at a 10 mm distance for 15 s with one dose of 22.5 mJ/cm². Fluorescent marker (STYO9-PI) was used to label (green = live bacteria, red = dead bacteria), and confocal microscopy was used to image the bacteria.

Results: In vitro results showed all plates treated with UVCT had 100% bactericidal effect for all isolates with single dose of 15 s at 10 mm distance or two doses, 4 h apart at 15 mm and was ineffective with single dose at 15-20 mm. The ex vivo results confirmed a significant decrease in bacterial load for all isolates on samples inoculated superficially but were inconclusive for intrastromal ones.

Conclusions: UVCT confirmed the therapeutic potential for all tested isolates, for both in vitro and ex vivo experiments using a single exposure of 15 s. While safety studies are underway, clinical trials are warranted.

Objective: To describe a combined treatment approach for heterochromic iridocyclitis and secondary keratitis (HIK) in horses.

Animal studied: A total of 15 horses (16 eyes).

Procedures: Sixteen eyes from 15 horses (mean age 14.1 years, range 6-26 years) received low-dose (4 mg) intravitreal preservative-free gentamicin injection (IVGI) and modified Gundersen grafts with standing sedation and local anesthesia following a clinical diagnosis of HIK. Additional therapies of suprachoroidal triamcinolone (8 mg) injection, episcleral bromfenac implants, and suprachoroidal cyclosporine implants were performed in individual cases. Leptospira titers were also reported when available.

Results: The most frequent ophthalmic findings were pigmented keratic precipitates (n = 15/16 eyes, 94%), corneal edema (n = 14/16 eyes, 88%), and pigmented cells suspended in the anterior chamber (n = 7/16 eyes, 44%). Postoperative treatment generally consisted of topical and systemic NSAIDs, topical antibiotics, and a topical mydriatic agent. Complications included persistent corneal edema (7/16, 44%), corneal ulceration (6/16, 38%), graft failure requiring revision (2/16, 13%), stromal abscess (1/16, 6%), surgery site infection (1/16, 6%), and suspected retinal degeneration following IVGI (1/16, 6%). One case was enucleated 6 months after treatment (1/16, 6%). Of the 12 eyes with at least 3 months of post-treatment follow-up, 10 were comfortable and visual with static or improved symptoms of HIK.

Conclusions: This multimodal treatment approach aims to address both the anterior uveitis and endothelial decompensation frequently seen in horses with HIK. The surgery can be performed under standing sedation. Continued evaluation and long-term follow-up is necessary in all horses with HIK.

Objective: The application of canine amniotic membrane (cAM) for corneal reconstruction is widely used in the veterinary field. However, the information on biological properties and alternative forms of cAM for corneal wound healing is limited. This study aimed to investigate the proteomic profiles and corneal wound healing properties of cAM, cAM extract (cAME), and lyophilized cAM extract (cAMX).

Animal studied: A total number of 14 cAMs were sterilely harvested from healthy full-term puppies and randomly divided into three different forms: cAM (n = 14), cAME (n = 14), and cAMX (n = 14).

Procedures: Each form of cAMs was subjected to proteomic analysis using label-free liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS), followed by bioinformatic analysis. The proteins were classified into properties by comparing them with the literature search on human amniotic membrane (hAM) properties and the effect on corneal wound healing when given topically.

Results: The analyses identified 8136 proteins in cAM, 8211 proteins in cAME, and 7093 proteins in cAMX. A total number of 100 proteins were matched with proteins in hAM properties and were classified into anti-inflammatory, anti-fibrotic, anti-microbial, anti-angiogenic, promotion of epithelialization, analgesic, and support cell adhesion and growth properties. Furthermore, proteins with corneal wound healing effects were identified in cAME and cAMX.

Conclusions: cAM and its extracts contain numerous proteins, including proteins related to corneal wound healing properties. Additionally, cAME and cAMX showed proteins involved in corneal wound healing and their potential benefits for topical use in ophthalmology.

Purpose: To describe the clinical features surgical technique, early and long-term outcome with or without surgery, and histopathological findings of melanocytic anterior uveal lesions in young dogs.

Methods: Medical records of dogs at a guide dog facility removed from training due to a pigmented iris lesion were reviewed from 2014 to 2021. Selected dogs had surgical iridectomies performed.

Results: Iridal melanocytic lesions were characterized as well-delineated, pigmented, and flat (nevus) or raised (mass) lesions of the iris. Forty dogs (18 Labrador retrievers, 18 German shepherd dogs, 1 Golden retriever, 3 Labrador/Golden mixes) ranging from 0.5 to 3.1 years of age were affected unilaterally (n = 35) or bilaterally (n = 5). Sector iridectomy was performed in 13 dogs with prominent and well-isolated mass lesion and enucleation was carried out in 2 dogs with extensive lesions, while all other cases were monitored without surgical intervention. Postoperative complications included dyscoria (13/13), focal posterior synechia (9/13) and focal nonprogressive cataract (8/13). All eyes remained visual and comfortable up to 6.2 years post-iridectomy with no clinically identifiable local recurrence. Histopathology was consistent with uveal melanocytoma in all samples obtained surgically. All cases that did not undergo surgery remained free of complications up to 4.5 year post diagnosis.

Conclusion: Melanocytic anterior uveal lesions may be overrepresented in certain lineages of breeds and be present at a young age. While none of the eyes developed complications when monitored without surgery, early surgical excision of the mass by sector iridectomy yields noteworthy functional outcome and retention of a comfortable globe.

Objective: To describe the clinical and pathological characteristics of a neoformation suggestive of myxosarcoma in a cat's eyelid.

Animal studied: An 11-year-old mixed-breed castrated female cat presented with a nodule on the lower eyelid approximately 1.6 cm in diameter, multilobulated, non-ulcerated, soft, and adhered to both the skin and conjunctiva of the lower eyelid.

Procedures: The incisional biopsy revealed findings suggestive of a peripheral nerve sheath tumor. After performing an exenteration of the right eyeball to ensure a safe surgical margin, the tissue samples were sent for histopathological analysis and later for immunohistochemistry.

Results: Microscopic evaluation classified the mass as a grade-I mesenchymal neoplasm, suggesting myxosarcoma and malignant peripheral nerve sheath tumor as differential diagnoses. An immunohistochemical examination was carried out to differentiate the neoplasm. Once tumors of neural origin were excluded, the diagnosis of myxosarcoma was indicated as the most likely.

Conclusion: We report a presumed case of eyelid myxosarcoma in a cat, highlighting its relevance in the differential diagnosis in the evaluation of eyelid and conjunctival neoplasms in cats.

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.