Search

Objective To describe ophthalmic abnormalities secondary to periocular and ocular snakebite in dogs. Animal Studied Retrospective review of medical records from dogs presenting to the Small Animal Hospital at University of Florida following snakebites to the face (2012–2014). Two groups were identified: periocular bites (PB) and ocular bites (OB). Results Records from eleven dogs matched the search criteria and were included in the study (PB=9, 81.8%; OB=2, 18.2%). Both OB cases involved the cornea. Facial edema, blepharospasm, chemosis, and conjunctival hyperemia occurred in all cases (100%). Hemorrhage from the eyelids occurred in eight cases (72.7%; PB=7, OB=1). Subconjunctival hemorrhage occurred in seven cases (63.6%; PB=6, OB=1). Third eyelid laceration and nictitans gland prolapse occurred in 1 case each (9%; PB=1). Lagophthalmia was present in three cases (27.3%; PB=3), with secondary corneal ulcer in two cases (18.2%; PB=2). Corneal ulcer due to direct corneal bite occurred in two cases (18.2%—partial thickness with melting 1 and full thickness 1). Uveitis was present in 6 cases (54.5%; PB=4, OB=2), with flare and miosis in 4 cases (36.4%; PB=2, OB=2). Hyphema, fibrin in anterior chamber, and cataract occurred in one case (9%; OB=1). Vision loss occurred in two cases (18.2%; PB=2), secondary to retinal degeneration (PB=1) and amaurosis (PB=1). Mean follow-up time was 7 weeks (range: 3 days–11 months). Most clinical signs had resolved by last examination. Conclusions Periocular symptoms were more commonly observed than ocular alterations, regardless of bite location. Appropriate supportive therapy should be instituted according to clinical signs.

Soft tissue often displays marked age-associated stiffening. This study aims to investigate how age affects scleral biomechanical properties in a canine glaucoma model with ADAMTS10 mutation, whose extracellular matrix is concomitantly influenced by the mutation and an increased mechanical load from an early age. Biomechanical data was acquired from ADAMTS10-mutant dogs (n = 10, 21 to 131 months) and normal dogs (n = 5, 69 to 113 months). Infusion testing was first performed in the whole globes to measure ocular rigidity. After infusion experiments, the corneas were immediately trephined to prepare scleral shells that were mounted on a pressurization chamber to measure strains in the posterior sclera using an inflation testing protocol. Dynamic viscoelastic mechanical testing was then performed on dissected posterior scleral strips and the data were combined with those reported earlier by our group from the same animal model (Palko et al, IOVS 2013). The association between age and scleral biomechanical properties was evaluated using multivariate linear regression. The relationships between scleral properties and the mean and last measured intraocular pressure (IOP) were also evaluated. Our results showed that age was positively associated with complex modulus (p

Objective To evaluate effects of Coherin™ on intraocular pressure (IOP), pupil size (PS), and heart rate (HR) in glaucomatous Beagles in single-dose studies in a pilot study. Materials and methods Intraocular pressure, PS, and HR were measured in eight glaucomatous Beagles. One randomly chosen eye received single 50 μL doses of differing concentrations of Coherin™ (treated eye) or vehicle (placebo-treated eye), and the fellow eye served as the untreated control. After the first measurements, a single dose of either Coherin™ or sterile water vehicle was instilled in the drug and placebo eyes, respectively. Results The mean ± SEM diurnal changes in IOP after 0.005%, 0.01%, 0.2%, 0.284%, 1%, 2%, and 4% topical Coherin™ once daily were 7.6 ± 3.2 mmHg, 15.5 ± 5.3 mmHg, 11.2 ± 4.4 mmHg, 11.8 ± 4.4 mmHg, 19.1 ± 3.8 mmHg, 5.0 ± 1.8 mmHg, and 8.8 ± 2.8 mmHg, respectively. The declines in IOP were significantly different (P

Objective To evaluate the changes in intraocular pressure (IOP) and pupil size in 12 Beagles with inherited glaucoma after instillations of 0.033, 0.0033, 0.001, 0.00033, and 0.0001% travoprost (Travatan®-Alcon Laboratories, Inc., Ft Worth, TX, USA) in multiple single-dose studies. Procedures Intraocular pressure and pupil diameter (PD) measurements were obtained at 9 am, 12 pm, 3 pm, and 9 am the following day (24 h) in two groups of six glaucoma dogs. After 7 days, the vehicle or concentration was repeated in the contralateral eye of the same animals. Results Concentrations of 0.00033, 0.001, and 0.0033% travoprost significantly lowered IOP and PD, but the 0.0001% concentration provided limited IOP changes, although PD changes were still significant. This suggests travoprost is effective in the dog to lower IOP and reduce pupil size at concentrations starting between 0.0001 and 0.00033%. Conclusions The dose response for travoprost in the glaucomatous Beagle indicates this model is highly sensitive to this group of drugs, even at concentrations as low as 0.00033% (1/12 the commercially available concentration).

Objective The gene (myocilin: MYOC) has been attributed to be involved in over 6% of inherited types of human glaucoma, the highest correlation for any gene to date. This study determines myocilin protein levels in the aqueous humor (AH) of normal laboratory quality, genetic carrier (offspring of normal laboratory quality and POAG Beagles), and primary open angle glaucoma (POAG) Beagles. Materials and methods Eighteen dogs were used and classified as either normal, carrier or having mild, moderate or advanced POAG. A 0.1-mL sample of AH was drawn from the anterior chamber of each dog in the study and frozen on dry ice. A modified Coomassie stain and Western blot, using a polyclonal rabbit antihuman myocilin antibody (Santa Cruz Biotechnologies, Santa Cruz, CA), was run on each sample to compare the myocilin levels. A purified human trabecular meshwork excreted myocilin protein sample was used as a control (Alcon Research Laboratories, Fort Worth, TX) and its band/densitometry measurement was defined as one unit of myocilin for comparisons. Results Comparisons of AH myocilin levels differed among normal laboratory quality, genetic carrier, and POAG Beagles at different stages of the disease. In the normal laboratory, Beagles the AH myocilin measured 0.817 ± 0.075 units (mean ± SEM); in the carrier Beagles the AH myocilin was 3.117 ± 0.290 units. As POAG progressed, myocilin protein levels also increased to 6.097 ± 0.810, 8.844 ± 1.079, and 17.228 ± 1.198 units in the early, moderate, and advanced forms, respectively. Overall comparisons between normal, carrier and all POAG Beagles combined showed significant differences (P

Objective To evaluate the visual outcome of three techniques of corneal transplantation surgery in treating severe inflammatory keratopathies in the horse. Design Retrospective medical records study. Animals studied Medical records of 206 horses that received corneal transplantation surgery at the University of Florida Veterinary Medical Center from 1993 to 2007 were reviewed. Procedure Data collected from the medical records included signalment, types of ocular lesions, type of transplant surgery performed, length of follow-up, complications, and visual outcomes. Results Full thickness penetrating keratoplasty (PK) was performed in 86 horses for melting ulcers, iris prolapse/descemetoceles, and medically nonresponsive full thickness stromal abscesses (SA). Posterior lamellar keratoplasty (PLK) and deep lamellar endothelial keratoplasty (DLEK) are split thickness penetrating keratoplasties that were utilized for medically nonresponsive deep stromal abscesses (DSA) in 54 and 66 eyes, respectively. The most common postoperative surgical complication was graft rejection and varying degrees of graft opacification. Wound dehiscence and aqueous humor leakage was also a common postoperative problem. A positive visual outcome was achieved for PK, PLK, and DLEK in 77.9%, 98.1%, and 89.4%, respectively. Conclusions Corneal transplantation is a tectonically viable surgery in the horse with an overall success rate of 88.5% in maintaining vision when treating vascularized and infected corneal disease in the horse.

This presentation on comparative and veterinary ophthalmology is divided into three sections : (1) ophthalmology in its infancy up until 1900, and founding period from 1901 to 1960 ; (2) ophthalmology as we know it today evolved from 1961 to 1980, and became a premier specialty in veterinary medicine (1981-now) ; and (3) the future in ophthalmology. Technology has had a profound effect on the development of ophthalmology with the discovery of the microscope and later on of the ophthalmoscope. Most of the early developments in veterinary ophthalmology occurred in Europe where schools of veterinary medicine had been established for decades. America was slow to recognize the specialty of veterinary ophthalmology, due to a lack of resources, time, and faculty devoted to clinics in the veterinary schools, and to additional constraints in small animal medicine and surgery. Veterinary ophthalmic pathology developed simultaneously and played a key role in clinical advances, resulting in the publication of significant textbooks on veterinary ophthalmology. Between 1960 and now, the majority of veterinary ophthalmologists have continued to contribute actively to this discipline. Significant advances during this period include : (1) the creation of veterinary ophthalmology societies or associations ; 2) the creation of certifying veterinary ophthalmology boards (colleges) ; 3) the introduction of veterinary ophthalmology programs in academia ; 4) the creation of clinical residencies for board certification ; 5) the rapid emergence of private referral practices in ophthalmology ; and 6) the advancement of veterinary ophthalmology research worldwide. With half a century of experience and significant progress, veterinary ophthalmology is facing a bright future with opportunities, along with potential difficulties. Our academic programs seem to have stalled in size while the number of private veterinary ophthalmology practices has exploded. Our capacities in clinical diagnosis and management of animal patients were greatly helped by the introduction of non-invasive imaging of the outer and deeper eye, as well as by the continuous development of new drugs. Human and veterinary ophthalmology are expected to benefit from further advances in both medical and surgical treatments. However, we need more research in breed-specific eye diseases, especially in dogs which appear second to man in the number of inherited eye diseases., L’ophtalmologie vétérinaire : passé, présent et futur Cet article sur l’ophtalmologie comparative et vétérinaire est divisé en trois périodes. (1) Avant 1900, avec les prémices de l’ophtalmologie, et de 1901 à 1960 quand ont été développées les bases fondatrices ; (2) l’ophtalmologie a acquis sa forme actuelle de 1961 à 1980 et est devenue une spécialité phare en médecine vétérinaire dès 1981 ; et (3) l’avenir de l’ophtalmologie. Les progrès en médecine humaine et vétérinaire dépendent au moins en partie de l’évolution de la société et de l’économie, associée aux progrès technologiques. Les progrès technologiques ont contribué de façon importante au développement de l’ophtalmologie, avec l’invention du microscope et ensuite de l’ophtalmoscope (Hermann von Helmholtz, 1850). Les premières avancées en ophtalmologie vétérinaire ont eu lieu en Europe où les écoles de médecine vétérinaire existaient déjà depuis des décennies. En France, Eugène Nicolas, vétérinaire de l’armée, a écrit trois livres sur l’ophtalmologie vétérinaire et comparative en 1898, 1914 et 1928. En Allemagne, l’ophtalmologie vétérinaire a pris son essor entre 1875 et 1910, à partir des écoles vétérinaires de Berlin, Stuttgart, Munich, et Vienne. Rudolf Berlin (1833-1897), ophtalmologue humain, a co-édité avec Oscar Eversbush (Munich) la première revue sur l’ophtalmologie vétérinaire (Zeitschrift für vergleichende Augenheilkunde) publiée de 1882 à 1893. Après avoir terminé ses études de médecine, Josef Bayer (1847-1925) est devenu vétérinaire en 1874 et ensuite professeur à la Faculté Vétérinaire de Vienne. Bayer est surtout connu pour son ouvrage pionnier et exhaustif sur l’ophtalmologie vétérinaire, Augenheilkunde, publié en 1900, et réédité en 1906, 1910, et 1914. Aux Pays-Bas, Jakob est surtout connu pour ses deux livres, Tierärztliche Augenheilkunde (1920) et Pathologische Anatomie des Auges der Tiere (1927). Henry Gray (1865-1939), un des premiers praticiens de petits animaux à Londres (1887), a traduit en anglais la deuxième édition du livre de Nicolas Ophtalmologie Vétérinaire et Comparée, le premier ouvrage sur l’ophtalmologie du début du XXe siècle ! Les États-Unis ont tardé à reconnaître l’ophtalmologie en tant que spécialité vétérinaire, à cause d’un manque de ressources, de temps et d’enseignants alloués aux cliniques dans les écoles vétérinaires, et des contraintes supplémentaires existant en médecine et en chirurgie des petits animaux. W. N. Sharp, médecin au Indiana Veterinary College et Indianapolis City Hospital, a écrit un petit livre intitulé Ophthalmology for Veterinarians. L’anatomie pathologique en ophtalmologie vétérinaire s’est développée en même temps et a fourni des bases essentielles au développement de l’ophtalmologie vétérinaire clinique. Parmi les ouvrages significatifs, on note Pathologische Anatomie des Auges der Tier (Jakob 1927), et Lehrbuch der Pathologischen Anatomie der Haustiere (Kitt 1901, deuxième édition). De 1960 à nos jours, la majorité des ophtalmologues vétérinaires ont continué de contribuer activement à cette discipline. Des progrès significatifs ont été accomplis durant cette période, tels que 1) la création de sociétés ou associations d’ophtalmologie vétérinaire ; 2) la création de certificats de spécialité en ophtalmologie vétérinaire ; 3) l’instauration de programmes d’ophtalmologie vétérinaire dans les études ; 4) la création de postes d’interne des cliniques pour l’obtention d’un diplôme en ophtalmologie ; 5) l’émergence rapide des cabinets privés spécialisés en ophtalmologie ; et 6) la promotion de la recherche en ophtalmologie vétérinaire dans le monde entier. L’ophtalmologie vétérinaire entame le XXIe siècle avec un demi-siècle d’expérience et de progrès significatifs derrière elle. Forte de ses bases solides, l’ophtalmologie vétérinaire peut se réjouir d’un avenir brillant, riche d’opportunités mais aussi de difficultés potentielles. L’expansion de nos programmes académiques semble s’être arrêtée, tandis que la création de cabinets vétérinaires privés spécialisés en ophtalmologie a explosé. Le développement actuel de l’imagerie non invasive des structures externes et internes de l’oeil, depuis l’échographie (y compris Doppler) jusqu’à l’imagerie au laser, a largement contribué aux progrès réalisés dans le diagnostic clinique et la prise en charge des pathologies oculaires chez l’animal. L’ophtalmologie humaine et vétérinaire peut encore s’attendre à de nouvelles avancées dans la thérapeutique médicale et chirurgicale, notamment avec l’arrivée de nouveaux médicaments. Ainsi, les prostaglandines topiques (PGF) ont apporté des bénéfices significatifs dans le traitement du glaucome chez le chien. Il faut poursuivre la recherche sur les maladies oculaires spécifiques de certaines races, particulièrement chez le chien qui occupe la deuxième position après l’homme pour le nombre de maladies héréditaires oculaires., Gelatt Kirk N. Veterinary ophthalmology: our past, present and future. In: Bulletin de l'Académie Vétérinaire de France tome 161 n°4, 2008. pp. 299-306.

Purpose To document differences in the levels of the endothelin-1 peptide, nitric oxide, and glutamate in aqueous humor and vitreous in the dog eye with spontaneous glaucoma compared to the normal dog eye. Methods Samples of aqueous humor and vitreous from enucleated normal eyes (n = 21) of 14 dogs and glaucomatous eyes (n = 8) of eight dogs were collected. Levels of endothelin-1, nitric oxide, and glutamate were measured by enzyme immunoassay. Results Endothelin-1 aqueous humor levels (mean +/- SD) increased significantly from 3.05 (+/- 1.66) pg/mL for the normal eyes to 6.22 (+/- 2.83) pg/mL for the glaucomatous eyes (P = 0.0054). The increase in vitreous from 1.83 (+/- 1.66) pg/mL for the normal eyes to 2.86 (+/- 1.31) pg/mL for the glaucomatous eyes was not significant (P = 0.0840). Nitric oxide levels (mean +/- SD) increased significantly in aqueous humor from 4.12 (+/- 2.64) microM for the normal eyes to 12.95 (+/- 14.42) microM for the glaucomatous eyes (P = 0.0141). The vitreous levels increased from 4.86 (+/- 3.92) microM for the normal eyes to 15.33 (+/- 16.22) microM for the glaucomatous eyes (P = 0.0179). Glutamate levels (mean +/- SD) decreased nonsignificantly in aqueous humor from 2.35 (+/- 3.84) microM for the normal eyes to 1.61 (+/- 0.74) microM for the glaucomatous eyes (P = 0.9377) and in vitreous from 1.37 (+/- 1.89) microM for the normal eyes to 1.02 (+/- 1.11) microM for the glaucomatous eyes (P = 0.3303). Conclusion Endothelin-1 and nitric oxide increased in aqueous humor and vitreous of dogs with spontaneous glaucoma while the changes in glutamate varied.

Maintenance and repair of corneal stromal extracellular matrix (ECM) requires a tightly coordinated balance of ECM synthesis, degradation and remodeling in which proteolytic enzymes (proteinases) perform important functions. There are natural proteinase inhibitors present in preocular tear film (PTF) and cornea simultaneously with proteinases that prevent excessive degradation of normal healthy tissue. Disorders occur when there is an imbalance between proteinases and proteinase inhibitors in favor of the proteinases, causing pathologic degradation of stromal collagen and proteoglycans in the cornea. Two matrix metalloproteinases (MMPs), MMP-2 and MMP-9, are of major importance in terms of remodeling and degradation of the corneal stromal collagen. Immunohistochemical studies have shown different origins of MMP-2 and -9. MMP-2 is synthesized by corneal keratocytes and performs a surveillance function in the normal cornea, becoming locally activated to degrade collagen molecules that occasionally become damaged. Alternatively, MMP-9 may be produced by epithelial cells and polymorphonuclear neutrophils following corneal wounding. Because the cornea is in close contact with the preocular tear film (PTF), proteinases have been evaluated in the PTF. In damaged corneas, total proteolytic activity in the tear fluid was found to be significantly increased compared to normal eyes and contralateral eyes. Studies analyzing the proteolytic activity in serial PTF samples during corneal healing led to the following conclusions: ulcerative keratitis in animals is associated with initially high levels of tear film proteolytic activity, which decrease as ulcers heal; proteinase levels in melting ulcers remain elevated leading to rapid progression of the ulcers. The success of medical and surgical treatment of the corneal ulcers is reflected by the proteolytic activity in tears. In animals, successful treatment leads to a rapid reduction in tear film proteolytic activity that corresponds with the improvement in the clinical signs of corneal ulceration. The in vitro effects of various compounds on proteolytic activity in the tear fluid of animals with ulcerative keratitis have been evaluated and their important inhibitory effects have been confirmed. Because these various compounds utilize different mechanisms to inhibit various families of proteinases, a combination of these proteinase inhibitors may be beneficial.

Objective The purpose of this study was to evaluate the effectiveness of postoperative beta-irradiation with strontium-90 as an adjunctive treatment to superficial keratectomy and permanent bulbar conjunctival graft for removal of equine corneolimbal squamous cell carcinoma (SCC), in decreasing recurrence rate. Study The retrospective case study included 38 horses diagnosed and treated for SCC of the eye that involved the limbus and/or cornea. The patients were treated between 1990 and 2002, with strontium-90 irradiation immediately after corneal and conjunctival graft surgery. Recurrence was defined as the postoperative and postirradiation regrowth of SCC in the same site and globe that was previously treated. Results The Appaloosa was the most commonly represented breed and horses that had more than one base coat color represented the majority of the cases (53%). The coat colors of white, chestnut/sorrel and gray were the most commonly represented colors of the horses treated. Eight horses (21%) could not be assessed for tumor recurrence due to lack of two or more post-treatment examinations, and another horse was enucleated 6 days postoperatively due to progressive corneal ulceration. Twenty-four horses (63% of the entire study population; 83% of the followed cases) had a mean ± SD of 1754 ± 1319 days without tumor recurrence, ranging from 14 days to 5110 days. Five horses (13% of the entire study population; 17% of the assessed horses) had tumor recurrence at a mean ± SD of 449 ± 339 days with a range of 29 days to 900 days. For the five recurrences, treatment included local excision (n = 1), enucleation (n = 2), and additional strontium-90 therapy (n = 3). Conclusions The combination of superficial keratectomy, β-irradiation and permanent bulbar conjunctival grafts for limbal, corneal or corneolimbal SCC in horses is effective in at least 83% of the horses. Recurrence occurred in about 17% of the horses. Multiple biannual re-examinations are recommended to observe for tumor recurrence.

Objective To determine whether the combination multiple-dose dorzolamide–timolol administered topically has any greater effects on the reduction of intraocular pressure, pupil size, and heart rate in dogs with glaucoma than do either timolol or dorzolamide alone. Procedure Applanation tonometry, pupil size, and heart rate measurements were made at 7 a.m., 1 p.m., and 7 p.m. daily of 12 laboratory Beagles with inherited primary open-angle glaucoma during each active phase of this study. Timolol 0.5% was administered first twice daily for 4 consecutive days. Dorzolamide 2.0% was administered next three times daily for 4 consecutive days. The fixed combination of the two (timolol 0.5% and dorzolamide 2.0%) was administered twice daily for 4 consecutive days during the final week of the study. Between administration of each drug, a withdrawal period of at least 10 days was instituted. Statistical comparisons between the effects of the three drugs were performed. Results Intraocular pressure (IOP) was decreased with the administration of all three drugs: timolol alone, dorzolamide alone, and the combination of the two decreased IOP after 1 day of treatment 2.83 ± 0.70 mmHg, 6.47 ± 0.32 mmHg, and 6.56 ± 0.37 mmHg, respectively. After 4 days of treatment, the IOP decreased even further: timolol alone, dorzolamide alone, and the combination of the two decreased IOP 3.75 ± 0.88 mmHg, 7.50 ± 0.29 mmHg, and 8.42 ± 0.58 mmHg, respectively. Heart rate was significantly decreased with timolol (−11.9 ± 2.0 bpm) and the combination preparation (−8.6 + 2.4 bpm), but not with dorzolamide (−3.7 ± 1.8 bpm) alone. Pupil size was significantly decreased with timolol (−1.42 + 0.40 mm) and the combination preparation (−1.3 + 0.33 mm), but not with dorzolamide (0.97 ± 0.36 mm) alone. Conclusions The combination dorzolamide–timolol appears to be more effective at reducing intraocular pressure in glaucomatous dogs than is either timolol or dorzolamide alone.