Veterinary ophthalmology最新文献

Objective: Determine if feeding two teaspoons per ten pounds of body weight per day of Saco powdered buttermilk (SPB) for 8 weeks affects salivary pH (SpH), magnesium (Mg), phosphorus (Phos), calcium (Ca), or total protein (TP) in dogs.

Animals: Eighteen dogs were enrolled following owner consent. Dogs with severe dental disease or that had been administered antibiotics in the past 3 months were excluded.

Procedures: Fasted saliva samples were collected using Salivette tubes within the same hour on Days 0, 1, 30, 31, 60, 61, 90, and 91. pH was measured immediately upon collection, samples were then mailed for laboratory analysis. SPB was administered at a dose of two teaspoons per ten pounds of body weight per day on Days 1-60. Baseline complete blood counts and serum chemistries were run before saliva collection on Day 1.

Results: Sixteen dogs completed the study. Side effects included flatulence (2) and loose stool (1). Salivette cotton swab ingestion occurred twice prior to change in method of securing swab during collection. Weight remained stable. There was no significant change in SpH, TP, Ca, or Phos during the study. There was a statistically significant, linear increase in Mg (p = 0.0065).

Conclusions: Feeding two teaspoons per ten pounds of body weight per day for 8 weeks did not significantly affect salivary pH, total protein, calcium, or phosphorus. There was a small linear increase in salivary magnesium concentration over the study period that did not return to baseline within 30 days of discontinuation of buttermilk supplementation, significance of which is unknown.

Purpose: Corneal sequestrum is a condition commonly observed in cats, though the pathogenesis is not fully understood. The occurrence of conjunctival sequestrum has not previously been documented. This report aims to describe a series of cases of conjunctival sequestra in cats.

Animals and animal samples studied: A 3-year-old male Persian cat presented after 2 months of blepharospasm and epiphora in the right eye, accompanied by mild conjunctival hyperemia. Histopathologic findings from four other cases are also included.

Methods: After presentation of Patient 1, the database (from 2007 to 2025) of the Comparative Ocular Pathology Laboratory of Wisconsin (COPLOW) was searched for other cases of feline conjunctival sequestrum, four of which were identified. In all cases, an amorphous black plaque was observed in the conjunctival tissue during the ophthalmological examination. Three of the four cases also had corneal sequestra ipsilaterally. Histopathology of the corneal sequestra was available in two of the cases.

Results: Histopathology of all five conjunctival lesions revealed focally extensive compaction and brunescence of proprial collagen and absence of fibroblasts. Three of the cases had conjunctival ulceration overlying the sequestrum. The surrounding substantia propria was variably infiltrated by inflammatory cells and microorganisms. The appearance of conjunctival sequestra was remarkably similar to that of corneal sequestra.

Conclusion and clinical relevance: This is the first reported case-series of feline conjunctival sequestrum. Variable presentation of concurrent ocular abnormalities and history led to no definitive conclusion to a common cause. Similar to corneal sequestra, chronic irritation and a possible contribution from FHV-1 infection are suspected.

Background: Squamous cell carcinoma (SCC) is one of the most common malignant eyelid tumors in cats, especially in white-haired individuals chronically exposed to sunlight. Electrochemotherapy (ECT), which combines bleomycin administration with transient membrane permeabilization through electric pulses, has demonstrated efficacy in periocular epithelial tumors. However, its use as monotherapy for third eyelid SCC has not been reported.

Objectives: To describe the clinical outcomes, feasibility, and safety of ECT as sole treatment for third eyelid SCC in two cats.

Methods: Two client-owned cats with histologically confirmed SCC restricted to the third eyelid underwent full staging, including thoracic radiographs and head CT. Both were treated with a single ECT session involving systemic and intratumoral bleomycin followed by electric pulses. Follow-up consisted of clinical and imaging evaluations for up to 930 days.

Results: Both cats achieved complete remission after one session. No recurrence or metastasis was detected during long-term follow-up. Treatment was well tolerated, with only mild, self-limiting inflammation. Ocular structures and function were fully preserved, without systemic toxicity. Owners expressed high satisfaction due to the non-invasive nature of ECT and the avoidance of enucleation.

Conclusions: This is the first report of successful ECT monotherapy for feline third eyelid SCC. The findings support ECT as a safe, effective, and organ-sparing option when surgery is declined or contraindicated, highlighting its potential role in feline ocular oncology and comparative oncology. Although promising, the very limited sample size (n = 2) prevents strong conclusions, and results should be regarded as preliminary observational evidence.

The decolonisation of veterinary education is an emerging topic in academic discourse. Introduced to the concept during a postgraduate certificate in veterinary education, I was surprised by how little literature or guidance existed on the subject. This article is not written from a place of authority, but from a desire to kindle an important conversation, one that examines how colonial legacies continue to shape veterinary curricula, research practices, and access to the profession itself. Drawing on personal experience, blog posts, and scientific literature, I explore how knowledge hierarchies formed through colonialism continue to privilege Western science while sidelining indigenous and ethnoveterinary practices. From "helicopter research" to the underrepresentation of individuals of colour in the veterinary profession, this article traces how colonial dynamics remain embedded in the educational, research, and professional systems we often consider neutral or progressive. Rather than offering a prescriptive solution, this paper aims to spark curiosity, discussion, and action. It suggests that decolonisation begins with personal and institutional insight and reflection and emphasises that meaningful change requires humility, inclusion, and a willingness to confront discomfort. The goal is not to reject existing knowledge, but to enrich it by integrating perspectives that have long been ignored or undervalued. By opening up this discussion, I hope to contribute to a more honest, inclusive, and forward-thinking vision of veterinary education, one that better serves a diverse global community of practitioners, researchers, and animal owners.

Objective: To determine if the area of the canine optic nerve head (ONH) is related to the peripapillary retinal nerve fiber layer (RNFL) thickness.

Animals studied: A total of 44 eyes of 22 adult normal laboratory Beagles.

Procedures: In this retrospective study, confocal scanning laser ophthalmoscopy (cSLO) and spectral domain optical coherence tomography (SD-OCT) images were evaluated. The sum of eight RNFL thickness measurements along the 12° circular OCT b-scan around the ONH was used to represent the total number of retinal ganglion cell (RGC) axons. The area of the ONH was measured by tracing the outer edges of the ONH in the cSLO images and adjusted for axial globe length. Descriptive and Pearson correlation statistics were used to describe the distribution of the ONH sizes and the relationship between total RNFL thickness and ONH area.

Results: The ONH area distribution for all eyes combined was approximately symmetric with an overall mean (± standard deviation) of 129 ± 35 degrees². The ONH areas between right and left eyes showed a strong, significant linear correlation (r = 0.83, p = 0.00). The mean sum of the eight RNFL thicknesses measured along the 12° circular OCT b-scan around the ONH was 448 ± 50 μm. There was a moderate, significant positive linear correlation between peripapillary RNFL thickness and ONH area (r = 0.43, p = 0.004).

Conclusions: In laboratory Beagles, the ONH area is partly affected by the peripapillary RNFL thickness, representing the total RGC axon number forming the optic nerve.

Objective: To describe calvarial hyperostosis syndrome (CHS) as a potential and unusual cause of exophthalmos or epiphora in young dogs.

Animals studied: A nine-month-old female intact (case 1) and a two-year-old male intact Labrador Retriever (case 2).

Procedures: Patient history, including previous treatments, was documented. Both cases underwent physical and ophthalmological examinations, computed Tomography (CT), and histopathological analysis. Additional dacryocystorhinography (DCR) was performed in case 2.

Results: Lateral exophthalmos of the left eye was the primary clinical sign in case 1. In case 2, serous lacrimal discharge was observed without other signs of ocular irritation. A slightly thickened and firm area distal to the medial canthus of the right eye was also noted. In this case, Jones 1 test on the right side was negative, whereas Jones test 2 revealed increased resistance when flushing the nasolacrimal system. CT imaging in both cases identified solid, smoothly marginated new bone formation. In case 1, this involved the left frontal bone, occipital bone, parietal bone, and temporal bone. In case 2, the new bone formation affected the right lacrimal bone and frontal process of the maxillary bone, leading to encasement and narrowing of the nasolacrimal duct (NLD). Histopathological analysis revealed active bone remodeling with osteoblasts in case 1, while case 2 demonstrated regularly differentiated trabecular lamellar bone with intertrabecular spaces. No evidence of neoplasia or osteomyelitis was observed in either case. Taken together, these findings strongly support a diagnosis of CHS in both cases.

Conclusions: CHS involving flat bones can present as exophthalmos or epiphora and should be considered in the differential diagnoses of these conditions, particularly in young dogs.

Objective: To compare the effects of loteprednol etobonate (LE) and ketorolac tromethamine (KT) on pupil diameter (PD) and aqueous humor levels of prostaglandin E₂ (PGE₂), total protein (TP), and glutathione (GSH) following paracentesis-induced intraocular inflammation in cats.

Methods: Thirty cats (n = 10/group) underwent anterior chamber paracentesis at T1 and T2 (60 min apart). At T1, the right eye received one drop of LE, KT, or saline (CG). PD was measured at T1 and T2, and aqueous humor samples were analyzed for PGE₂, TP, and GSH.

Results: At T1, PD, PGE₂, TP, and GSH levels did not differ among groups (p > 0.05). At T2, PGE₂ concentrations were significantly lower in LE (p < 0.0001) and KT (p = 0.01) groups when compared to CG. When compared to CG, TP values were significantly lower only in the LE group (p = 0.002). GSH levels decreased significantly across all groups (p < 0.01), maintaining significantly higher levels in the LE group (p = 0.04). PD decreased significantly in the CG (p = 0.003) and KT (p = 0.01) groups, but not in the LE group (p = 0.18).

Conclusions: LE and KT effectively reduced PGE₂ levels following paracentesis. LE also significantly decreased TP levels, mitigated miosis, and preserved GSH, indicating reduced oxidative stress. Considering that KT also reduced PGE₂ levels, further studies are warranted to determine whether KT might effectively reduce protein influx into the anterior chamber at later time points.

Objective: To describe infracyanine green-based photodynamic therapy (InfraCG-PDT) and evaluate outcomes in horses with immune-mediated keratitis (IMMK).

Animals studied: Medical records from 2014 to 2020 from the Equine Clinic Munich-Riem, Germany, and Auburn University Equine Ophthalmology Service identified horses diagnosed with IMMK following ophthalmic examination that had undergone InfraCG-PDT.

Procedures: Multiple intrastromal injections of EmunDo (InfraCG, A.R.C. Laser, Nuernberg, Germany) within an affected quadrant or the entire cornea were treated with diffuse diode laser energy (FOX A.R.C., Laser, Nuernberg, Germany, 500 mW at 30s cycles) irradiation between 75 J (J, quadrant) and 300 J (entire cornea).

Results: Fifty-one eyes (22 OS, 19 OD, 10 OU) from 47 horses were included (22 geldings, 20 mares, and 5 stallions) from 15 breeds aged between 4 and 29 years (median 14 years). Individual quadrants (28/51 eyes, 54.9%) or the entire cornea (23/51 eyes, 45.1%) were treated. Complications were defined as immediate: intrastromal fracture (4/51 eyes, 7.8%), intracameral InfraCG (7/51 eyes, 13.7%), and an epithelial blister (1/51 eyes, 1.9%) or short term: prolonged dye retention (51/51 eyes, 100%, with gradual reduction over a 12-week period) and superficial corneal ulceration (15/51 eyes, 29.4%). Globe threatening ulcers (3/51 eyes, 5.9%) resolved without significant complications. IMMK remained inactive (controlled or managed with improvement in ocular lesions) in 31/40 horses (77.5%) during follow-up (mean 223.0 ± 269.3 days; range 14-1095 days), 4/40 horses (10.0%) required additional treatment, and 5/40 horses (12.5%) were lost to follow-up.

Conclusions: InfraCG-PDT may be an effective treatment for horses with IMMK. Further studies are needed to optimize this treatment modality.

Objective: This study aims to investigate the presence, microanatomical localization, and immunohistochemical subtypes of mast cells in the lacrimal glands (LGs) of rats.

Animals: A total of ten female Sprague-Dawley rats' LGs were evaluated in this study.

Procedure(s): The experimental animals were euthanized. LG samples were collected and fixed in 10% neutral formaldehyde for 48 h. Sections were taken from the paraffin-embedded samples and stained for microscopic examination. The histochemical properties of lacrimal gland epithelium and the composition of tears were examined by Periodic acid-Schiff and Alcian blue staining and evaluated microscopically. Toluidine blue staining and tryptase and chymase immunohistochemically demonstrated localization and phenotypes of mast cells.

Results: The existence and varying numbers of mast cells were successfully demonstrated in all three LGs by Toluidine blue staining, and the highest number of mast cells was observed in the extraorbital lacrimal gland, while their numbers were almost the same in the intraorbital lacrimal gland and Harderian gland. Immunohistochemically, chymase-positive mast cells were more numerous than tryptase-positive cells.

Conclusions: This study is the first documentation of the presence of mast cells with different phenotypes in rat LGs.