PURPOSE:To evaluate the frequency of retinal detachments following prophylactic transpupillary retinopexy (PTPRP). METHODS:The medical records of dogs that received a PTPRP between 2014 and 2022 were retrospectively analyzed for age, sex, breed, reason for retinopexy, laser power setting, number of retinal burns, follow-up duration, and outcome. Laser power settings were increased until retinal burns could be visualized and were made 360° in a double row in the peripheral retina. RESULTS:Fifty-seven cases (75 eyes), 28 males and 29 females, had PTPRP performed. The median age was 8 years (4 months-14 years) with Shih tzu (n = 12), Bichon (n = 5), Miniature Poodle (n = 5), and Yorkie (n = 4) being the most common breeds. PTPRP were performed due to severe vitreal degeneration (n = 66), retinal detachment in the contralateral eye (n = 25), capsular tear with escaped lens material during phacoemulsification (n = 6), intracapsular lens extraction (n = 2), and lens luxation during phacoemulsification (n = 3). The median power setting, number of retinal burns, and follow-up time were 300 mW (201-595 mW), 210 burns (35-921 burns), and 473 days (14-1862 days), respectively. Additionally, five patients had a barrier-pexy performed in the contralateral eye, due to partial detachment. Retinal detachment occurred in 3/75 (4.0%) of eyes that received a PTPRP at the final examination. Of the patients with a detachment in the contralateral eye (n = 25), no detachment was noted at the last follow-up examination. Two partial detachments that had barrier-pexies had progressed at the final examination. CONCLUSIONS:These results demonstrate that PTPRP may be beneficial in decreasing the risk of retinal detachment in selected cases.

A 4-year-old mixed-breed dog was presented for hyphema and glaucoma of the right eye. Enucleation of the right globe was carried out, and histopathology examination revealed an optic nerve glioma with incomplete surgical margins. At 8 wk after surgery, the dog had depressed mentation and a diminished pupillary light reflex of the left eye. Magnetic resonance imaging revealed an irregular, heterogeneously T2 hyperintense/T1 isointense mass in the region of the optic chiasm. Compression of the rostral thalamus was present, with effacement of the pituitary gland and involvement of the right orbit. The dog was euthanized 4.5 mo after initial presentation. An undefined glioma of the right optic nerve with extension to the diencephalon was diagnosed on necropsy. Key clinical message: Although rare, intraocular glioma is a differential diagnosis for hyphema, glaucoma, and retinal detachment. Magnetic resonance imaging should be considered in cases of intraocular neoplasia, notably in those with incomplete surgical margins of the optic nerve.

Purpose:Bibliometrically analyze the 100 most-cited

OBJECTIVE Evaluate the effects of corneoconjunctival transposition (CCT), posterior lamellar keratoplasty (PLK) and modified deep lamellar endothelial keratoplasty (DLEK) on streak retinoscopy in equine cadaver eyes. METHODS Intraocular pressure (IOP) was maintained at 25 ± 3 mmHg in 35 equine cadaver eyes. Streak retinoscopy was performed prior to (NO VISCO) and following (VISCO) intracameral injection of 1.0 ml of viscoelastic. Following optical coherence tomography (OCT), an axial CCT [n = 11] or PLK [n = 12], or peripheral DLEK [n = 12] was performed. Streak retinoscopy and OCT were repeated postoperatively. RESULTS Postsurgical net meridional and spherical refraction for CCT [Horizontal (H): 3.4 (95% CI 2.4-4.4) diopters (D), p < .001, Vertical (V): 3.5 (95% CI 2.7-4.4) D, p < .001, Spherical: 3.5 (95% CI 2.6-4.3) D, p < .001] and PLK [H: 3.2 (95% CI 2.2-4.1) D, p < .001, V: 2.8 (95% CI 2.0-3.6) D, p < .001, Spherical: 3.0 (95% CI 2.2-3.8) D, p < .001] were significantly increased from presurgical (VISCO) values. No difference between presurgical (VISCO) and postsurgical values were identified for the DLEK. Postoperative OCT revealed space between anterior and posterior corneal grafts and corneal undulation associated with suture placement. CONCLUSION Meridional and spherical refraction had a hyperopic shift following CCT and PLK, with a significantly higher value in the vertical meridian for the CCT. Pre- and postoperative refraction was not significantly different for the DLEK. This supports that the DLEK has a lesser effect on immediate postoperative refraction compared with CCT or PLK.

OBJECTIVE To compare image quality and acquisition time of corneal and retinal spectral domain optical coherence tomography (SD-OCT) under 3 different sedation-anesthesia conditions in horses. ANIMALS 6 middle-aged geldings free of ocular disease. PROCEDURES 1 randomly selected eye of each horse was evaluated via SD-OCT under the following 3 conditions: standing sedation without retrobulbar anesthetic block (RB), standing sedation with RB, and general anesthesia with RB. Five regions of interest were evaluated in the cornea (axial and 12, 3, 6, and 9 o’clock positions) and fundus (optic nerve head). Three diagnostic scans of predetermined quality were obtained per anatomical region. Image acquisition times and total scans per site were recorded. Corneal and retinal SD-OCT image quality was graded on a subjective scale from 0 (nondiagnostic) to 4 (excellent). RESULTS Mean values for the standing sedation without RB, standing sedation with RB, and general anesthesia conditions were 24, 23, and 17, respectively, for total cornea scan attempts; 23, 19, and 19 for total retina-scan attempts; 14.6, 13.2, and 9.2 minutes for total cornea scan time; 19.1, 9.2, and 13.0 for total retina scan time; 2.0, 2.3, and 2.5 for cornea grade; and 2.7, 2.9, and 2.5 for retina grade. CONCLUSIONS AND CLINICAL RELEVANCE The RB facilitated globe akinesia and improved the percentage of scans in frame and region of interest accuracy for retinal imaging via OCT in horses. Retrobulbar blocks improved clinical image acquisition while minimizing motion artifact.

OBJECTIVE Investigate histopathology and spectral-domain optical coherence tomography (OCT) imaging of wild owls with chorioretinitis and identify any potential correlation with an infectious etiology. MATERIALS AND METHODS Ophthalmic examination and retinal OCT imaging were performed on fifteen great horned (Strix varia) and barred (Bubo virginianus) owls (30 eyes) with chorioretinitis and five owls with normal eyes (10 eyes). Testing to investigate the presence of potential infectious diseases included a complete blood count, biochemistry, protein electrophoresis, West Nile virus (WNV) plaque reduction neutralization test, Toxoplasma gondii modified direct agglutination test, WNV RT-PCR, and Avian Influenza RT-PCR. A necropsy was performed on all owls, including ocular histopathology. RESULTS Fundus lesions included retinal detachment (7/15 owls), depigmented lesions (12/15), pigment clumping (8/15), and retinal tear (4/15). All birds were negative for WNV and Avian Influenza on RT-PCR. Of the owls with chorioretinitis, 3/15 were seropositive for WNV and 7/15 for T. gondii. Optical coherence tomography of 25/30 affected eyes revealed outer retinal lesions (19/25 eyes), retinal detachment (16/25), and retinal tears (3/25). Histopathological examination revealed outer nuclear layer atrophy (19/30 eyes), retinal detachment (18/30), retinal tears (7/30), suprachoroidal hemorrhage (12/30), scleral rupture (3/30), and ossicle fracture (3/30). CONCLUSIONS Although 20% of birds were seropositive for WNV and 46.6% for T. gondii, histopathologic findings supported that the posterior segment lesions in the study group were likely due to blunt ocular trauma rather than an infectious etiology. The results of OCT imaging and histopathology documented retinal changes most consistent with blunt ocular trauma.

OBJECTIVE:To report the surgical excision of an iridociliary adenoma and iridal melanocytoma using a postero-anterior cyclo-iridectomy in two dogs.PROCEDURE:A 7 year old neutered male English springer spaniel (case 1) and a 7 year old neutered male Labrador mix (case 2) were presented for evaluation of an intrairidal mass OS.RESULTS:Complete ophthalmic examination revealed a large, dorsonasal, well-demarcated, intrairidal mass OS. A tan to pink intrairidal mass extending into the iridocorneal angle (case 1) and a pigmented intrairidal mass (case 2) were present. B-mode ultrasonography showed a focal, soft tissue, homogenous mass within the uvea adjacent to and contacting the lens. Neither pars plana involvement nor vitreal extension was present. A postero-anterior cyclo-iridectomy was performed through a polyhedral scleral flap. Thermocautery was used to complete the cyclo-iridectomy (case 1) and partial iridectomy (case 2) to excise the mass en bloc. Histopathology revealed a completely excised iridociliary adenoma (case 1) and iris melanocytoma (case 2). The surgery sites healed without complication. Mild uveitis (cases 1 and 2), scant vitreal hemorrhage (case 1), and mild hyphema (case 2) were present three days postoperatively but had resolved ten days postoperatively. The patients remain visual twenty-two months (case 1) and seven months (case 2) postoperatively with a normal intraocular examination other than an iridal defect and mild dorsonasal lens capsular opacities.CONCLUSIONS:The surgical approach described in these cases is utilized in physician-based medicine. This approach and the use of thermocautery provide a viable surgical option for excision of large iridociliary tumors in dogs.

Objective To compare complication rates and visual outcomes following phacoemulsification in Pugs versus dogs of other breeds. Animals studied Thirty-two pure-bred Pugs (55 eyes) and 32 dogs of other breeds (56 eyes) undergoing phacoemulsification. Procedures Multi-institutional retrospective medical record review of perioperative factors, postoperative complications, and visual outcomes. The reference population of dogs of varying breeds included surgical cases following each Pug case at the same institutions. Perioperative risk factors and postoperative complication rates were compared between the two populations. Results Pigmentary keratitis and diabetes mellitus were the most common preoperative comorbidities, found in 75% (P < .001) and 72% (P = .12) of Pugs, respectively. No perioperative factors were significantly associated with postoperative complications in Pugs. Postoperative complication rates were similar between groups; however, the most common complication in Pugs was corneal ulceration (15% of operated eyes), whereas glaucoma was most common in the reference population (13% of operated eyes). Three months postoperatively, vision was preserved in 91% of eyes of Pugs (50/55) and 95% of the reference population (53/56). One year postoperatively, 80% (32/40) of Pug eyes and 82% (28/34) of eyes in the reference population remained sighted. Conclusions Comorbidities and complications of cataract surgery in Pugs of this study demonstrate a predisposition for corneal disease. This highlights the importance of preoperative evaluation of factors associated with PK and corneal clarity, and postoperative monitoring for corneal ulceration in this breed.

OBJECTIVE To document a case series using corneoconjunctival transposition (CCT) surgery with and without bioscaffolding matrix (ACell® ) to repair deep corneal ulcers and perforations in dogs. ANIMALS STUDIED Eighteen dogs of various breeds that presented with deep or perforating corneal ulcers. PROCEDURES Corneoconjunctival transposition grafts with or without ACell® were sutured using a simple interrupted 8-0 or 9-0 polyglactin 910 pattern. RESULTS A total of eighteen dogs (19 eyes) were diagnosed with deep corneal ulcers (n = 7) and perforating corneal ulcers (n = 12). A CCT was performed in all eyes, with ten of them additionally receiving an ACell® graft. The majority of lesions were located axially in 14/19 (81%) eyes. Grafts were harvested from dorsal (n = 8), temporal (n = 5), ventral (n = 4), or nasal (n = 2) quadrants. Brachycephalic breeds (13/18) were over-represented. Keratoconjunctivitis sicca was present in 10/19 eyes (52.6%). Bacterial isolates were cultured from 8/19 eyes. Post-operative therapy included topical antibiotics, plasma, cycloplegics, oral antibiotics, and oral nonsteroidal anti-inflammatory drugs. CCT integration with and without ACell® occurred at a median of 20 days (range 7-38 days) post-operatively with no significant difference between groups. Median follow-up time was 188 days. Short-term post-operative complications included granulation tissue formation (19/19), corneal edema (4/19), graft retraction (4/19), and anterior synechia (1/19). Long-term complications in 14 eyes with follow-up >30 days included superficial corneal pigmentation (6/14) and epithelial inclusion cysts (5/14). Two eyes were nonvisual at last follow-up due to cataract formation. CONCLUSIONS Corneoconjunctival transposition with ACell® can be utilized for corneal ulcer repair in dogs.

Objective To describe and evaluate a modified penetrating keratoplasty technique utilizing ACell((R)) for management of equine deep stromal or full-thickness corneal stromal abscesses (SA).Methods Cases presenting to the University of Georgia Ophthalmology service for surgical management of SA necessitating penetrating keratoplasty (PK) were included in the study population. Surgery entailed the use of an ACell((R)) disk sutured within the deep level of a stepped full-thickness corneal incision with an overlying conjunctival pedicle flap placed in the superficial step incision. Patients were evaluated for success as defined by a comfortable, visual outcome.Results Surgery was performed in seven horses. Conjunctival flap incorporation and globe retention occurred in all patients. Functional vision was maintained in six of seven eyes (85.7%) at last follow-up examination (mean of 87.6 days [range 41-251 days]). Mean size of ACell((R)) implant was six millimeters (range 4-8 mm). Postoperative complications included moderate to severe anterior uveitis (n = 2), diffuse keratitis (n = 1), incipient cataract formation (n = 3), and anterior and posterior synechiae (n = 1).Conclusions This technique is a viable option for treatment of equine SA requiring PK. The use of bioscaffold implant is an alternative to frozen and fresh donor cornea transplantation.

Thirty dairy bull calves with normal ophthalmic examinations and culture-negative for Moraxella bovis were randomly assigned to 3 groups for a single eye block, randomized, blinded challenge study. Calves were housed in an accredited isolation facility. In calves assigned to Groups 1 and 2, a 0.6 cm corneal lesion was made on the left central cornea utilizing n-heptanol, and immediately inoculated topically with 1.0 x 107 of M. bovis (strain Epp63-300; origin: NADC). The left eye of calves in Group 3 was inoculated topically with M. bovis, but nothing further. In Group 1,2 mL of 0.009% hypochlorous acid (Vetericyn Plus™ Pinkeye Spray) was sprayed topically onto each calf's cornea twice daily for 10 days. In Group 2, 2 mL of 0.9% saline was administered topically to each calf’s cornea twice daily for 10 days. Each animal was scored for ocular pain twice daily. Samples from all eyes were collected for culture on days -7, 0,1,4, and 10. Eyes of all calves were stained daily with fluorescein, and digital photographs were taken of the lesion to assess healing of the cornea. Additionally, serum and plasma samples were collected from all calves on days 0,1,10,11, and 17, and changes in sodium and chloride levels were evaluated. Urine samples and liver, muscle, and fat biopsies were collected from all calves on days 0,11, and 17 and evaluated for chlorine utilizing the N,N-diethyl- p-phenylenediamine (DPD) colorimetric method. Only calves in Group 2 were culture-positive for M. bovis during the study period. The average pain score and days to cure for Group 1 was lower than Group 2 (P < 0.05 and P < 0.02, respectively). Corneal lesion circumference of calves in Groups 1 and Group 2 differed (P < 0.04), and the difference between days was significantly different (P < 0.0001). There was no difference in Na or Cl levels in the plasma and serum samples among the 3 treatment groups at any sampling time points (P< 0.0001), and no difference between pre- (day 0) and post-treatment (day 11 and 17) in chlorine levels in muscle, liver, fat, and urine at any time point. Results of this study suggest that hypochlorous acid spray can be utilized as alternative therapy to reduce pain, infection, and healing time of corneal lesions in calves experimentally infected with M. bovis.

OBJECTIVE To report and compare the success rate of a conjunctival pedicle flap (CPF) alone vs. a CPF with an underlying acellular submucosa implant for the repair of deep or perforating corneal wounds in dogs. PROCEDURES Records of 69 dogs (73 eyes) receiving a CPF with or without an acellular submucosa implant between 2004 and 2012 were reviewed. Successful outcome was defined as a comfortable eye with vision at the last post-operative evaluation. Age, breed, underlying corneal disease, surgical time, lesion characteristics, topical therapies, and postoperative complications were investigated. RESULTS Groups consisted of dogs that had a CPF alone (n = 37) and dogs that had a CPF plus an acellular submucosa implant (n = 36). Age, lesion size, surgical time, and time to discontinuation of topical anti-proteolytic medications was not significant between groups. Topical antibiotic use was terminated 13 days sooner (P ≤ 0.01) in dogs with an acellular submucosa implant. The combined success rate of all corneal wounds was 93% with success rate of corneal perforations, descemetoceles, and deep stromal wounds being 89%, 95%, and 100%, respectively. There was no difference in overall success rate between groups. Increasing age was associated with a negative outcome (P ≤ 0.01). Lesion size, presence of a corneal perforation, and concurrent keratoconjunctivitis sicca was not associated with a negative outcome. CONCLUSIONS A comparable success rate is achieved for deep or perforating corneal wounds stabilized with a CPF alone vs. a CPF plus acellular submucosa. Glaucoma, persistent uveitis, and cataract formation were not reported as post-operative complications in this study population.

OBJECTIVETo determine whether cortisol is present in equine tears at rest and during simulated stress and compare tear cortisol to serum free and total cortisol.MATERIALS AND METHODSFourteen healthy adult horses were included. Paired tear total cortisol and serum total and free cortisol concentrations were measured with ELISA, chemiluminescent immunoassay, and ultrafiltration methodology, respectively, in 10 horses at rest once daily for five consecutive days. In an additional four horses, paired tear and serum samples were collected for cortisol measurement before and after adrenocorticotropic hormone (ACTH) stimulation (cosyntropin, 1 μg/kg IV).RESULTSCortisol was detectable in equine tears at rest. Following ACTH stimulation, tear cortisol increased significantly from baseline at 60-120 min (P ≤ 0.001). Serum total and free cortisol also increased significantly at 30-180 min after ACTH stimulation (P ≤ 0.001). Both serum and tear cortisol returned to baseline concentrations by 360 min. Changes in tear cortisol were similarly associated with changes in serum total and free cortisol, although high tear cortisol concentrations suggest a portion of tear cortisol may be protein-bound.DISCUSSIONCortisol is present in equine tears and increases in concert with serum cortisol following ACTH stimulation. Further study is needed to determine whether endogenous cortisol in tears contributes to ocular pathology.

Fibropapillomatosis (FP), a transmissible neoplastic disease of marine turtles characterized by a likely herpesviral primary etiology, has emerged as an important disease in green sea turtles ( Chelonia mydas ) over the past three decades. The objectives of this study were to determine the suitability of three different chelonid fibropapilloma-associated herpesvirus (CFPHV) gene targets in polymerase chain reaction (PCR) assays of affected tissues; to explore the presence of CFPHV in non-affected skin from turtles with and without tumors; and to better understand tissue localization of the CFPHV genome in a tumor-free turtle by evaluating CFPHV presence in microanatomic tissue sites. Two aggregations of green sea turtles ( Chelonia mydas ) in Puerto Rico were evaluated, with six sampling intervals over the three-year period 2004–2007. Primary and nested PCR for three different herpesviral gene targets- DNA polymerase, capsid maturation protease, and membrane glycoprotein B- were performed on 201 skin biopsies taken from 126 turtles with and without external tumors. Laser capture microdissection and nested PCR were used to identify tissue localizations of CFPHV in skin from a normal turtle. Of the turtles sampled in Manglar Bay, 30.5% had tumors; at the relatively more pristine Culebrita, 5.3% of turtles sampled had tumors. All three PCR primer combinations successfully amplified CFPHV from tumors, and from normal skin of both tumored and tumor-free turtles. Via nested PCR, the polymerase gene target proved superior to the other two gene targets in the positive detection of CFPHV DNA. CFPHV infection may be common relative to disease incidence, supporting the idea that extrinsic and/or host factors could play a transforming role in tumor expression. Laser capture microdissection revealed CFPHV in skin from a tumor-free turtle, harbored in both epidermal and dermal tissues. Identification of CFPHV harbored in a non-epidermal site (dermis) of a tumor-free turtle indicates that virus is latent in a non-tumored host.

OBJECTIVEEquine recurrent uveitis (ERU) is a spontaneous disease that is the most common cause of blindness in horses, affecting up to 15% of the horse population. Th17 cells are a major cell population driving the pathogenesis in several mouse models of autoimmune inflammation, including experimental autoimmune uveitis. The purpose of this study is to investigate the role a Th17 cell-mediated response plays in the pathogenesis of ERU.PROCEDUREBanked, Davidson's-fixed equine globes histopathologically diagnosed with ERU (n = 7) were compared immunohistochemically with healthy control globes (n = 7). Immunohistochemical staining was performed using a pan-Leptospira antibody and antibodies against IL-6, IL-17, and IL-23. Additionally, immunostaining was performed for T-cell (CD3) and B-cell (CD79α) markers. Specificity of immunoreactivity was confirmed by western blot analysis.RESULTSImmunohistochemical staining was positive for IL-6, IL-17, and IL-23 within the cytoplasm of nonpigmented ciliary epithelial cells and mononuclear inflammatory cells infiltrating the iris, and ciliary body of ERU horses (n = 7) but negative in controls (n = 7). ERU-affected eyes were CD3 positive (n = 7) and CD79α negative (n = 7). Staining for Leptospira was negative in all ERU and control globes.CONCLUSIONSStrong immunoreactivity for IL-6, IL-17, and IL-23, in conjunction with the fact that T lymphocytes are the predominating inflammatory cells present in ERU, suggests that IL-17-secreting helper T-cells play a role in the pathogenesis of ERU. These findings suggest that horses with ERU may serve as a naturally occurring animal model for autoimmune uveitis.