Follicular conjunctivitis in dogs: A retrospective study (2007-2022).

OBJECTIVE: To evaluate the incidence, clinical features, treatment, and outcome of canine follicular conjunctivitis (CFC). PROCEDURE: Medical records of dogs diagnosed with CFC were reviewed. Data recorded included signalment, duration of clinical signs and treatment details prior to presentation, concurrent ocular/systemic diseases, ocular clinical signs, cytology, treatment, follow-up, and outcome. Blepharospasm, signs of self-trauma, hyperemia, chemosis, ocular discharge, and follicle location and severity (0.5-4) were retrospectively evaluated. Based on severity, treatment consisted of topical 0.1% diclofenac or 0.1% dexamethasone sodium eyedrops. Dogs were classified into young (YD < 18 months) and adult (AD ≥ 18 months). RESULTS: One hundred and fifty-three dogs (276 eyes) were included in the study: 83YD (54%) and 70AD (46%). Males and bilateral disease were over-represented in both groups. Severity was associated with young age (p = .032) and bilaterality (p = .025), and not with dermatological diseases (p > .05). No differences in follicular location were observed except for more frequent involvement of the nictitating membrane (MN) in YD (p = .02). Response to treatment was faster in AD (p = .001), with complete resolution in 80.6% of the eyes (100/124) at 1 month. YD treated with diclofenac showed faster resolution than those treated with 0.1% dexamethasone (p = .009). CONCLUSIONS: Although CFC is a bilateral ocular disease occurring at any age, the clinical presentation is influenced by age. Follicular conjunctivitis in adult dogs is less sever, less commonly affects the NM, and responds more quickly to topical treatment. One month of topical diclofenac may be adequate for mild cases, and 1 month of topical 0.1% dexamethasone is recommended as initial therapy for moderate to severely affected cases.

Topical 1% cyclosporine eyedrops for the treatment of crystalline corneal dystrophy in dogs.

Background: Crystalline corneal dystrophy (CCD) is the most common type of corneal lipidic deposition in dogs. CCD is a primary metabolic disorder of the corneal fibroblast featuring an accumulation of extracellular and intracellular lipid deposits. Corneal lipid deposits create a corneal opacity and modify the interfibrillar collagen distance, inducing light scattering. Corneal vascularization is not usually associated with the disease, but, in case of chronicity, cell death may produce inflammation, and new corneal vessels are developed. To the best of the authors' knowledge, this is the first report of a medical approach for CCD treatment in veterinary medicine. Aim: To evaluate the efficacy of topical 1% cyclosporine eyedrops (1% CsA) for the treatment of CCD in dogs. Methods: Medical records of dogs with CCD were retrospectively reviewed (2009-2020). Corneal opacification description (COD) [size (mm), depth, and opacification degree (0-3)] was evaluated at 0, 3, 6, 9, 12, and 15 months postinitial diagnosis. Dogs were classified into three groups: the control group (G0), the group receiving topical 1% CsA once per day (G1), and the group receiving topical 1% CsA twice daily (G2). Results: Ninety-two client-owned dogs (163 eyes) of different breeds, ages, and gender fulfilled the inclusion criteria. When compared to G0, where the eyes significantly increased COD (p < 0.001), G1 and G2 significantly decreased COD (p < 0.001). In fact, the probability of reducing COD was about three times higher in G2 than in G1, being nearly the same for the right [odds ratio (OR) = 2.94; 95% confidence interval (95% CI) = 0.55-15.78] and left eye (OR = 2.92; 95% CI = 0.49-17.26). In addition, for each additional month of treatment in G2, the probability of reducing COD increased significantly (OR = 1.12; 95%CI = 1.00-1.26 for the right eye and OR = 1.16; 95%CI = 1.02-1.32 for the left eye). Conclusion: Long-term treatment with topical 1% CsA eyedrops significantly improved CCD in dogs, being the probability of reducing COD higher when applying the treatment twice daily.

Diagnoses and key for the larvae of Progomphus Selys, 1854 from Argentina (Anisoptera: Gomphidae), with first larval descriptions for P. aberrans Belle, 1973 and P. kimminsi Belle, 1973.

Ten species of Progomphus Selys, 1854 are known to occur in Argentina. The larval stages of only four of them are described. We here add the larval descriptions of two species: P. aberrans Belle, 1973 and P. kimminsi Belle, 1973, and diagnose and illustrate important characters for the remaining species known at the larval stage in Argentina: P. complicatus Selys, 1854, P. joergenseni Ris, 1908, P. lepidus Ris, 1911 and P. phyllochromus Ris, 1918. New geographical records for these species are presented, including new records for P. kimminsi in Bolivia, and new provincial records in Argentina: P. aberrans and P. joergenseni in San Luis, and P. kimminsi in Santiago del Estero. A key to distinguish the larval stage of Argentinean species is proposed.

Prevalence of ocular findings and their association with glycemia in dogs with diabetes mellitus: A 10-year clinical study (2009-2019).

Background: Although ocular findings in diabetic patients are well described, prevalence data for those is unknown. Aim: To describe the prevalence of ocular findings and their association with glycemia in dogs with diabetes mellitus. Methods: Medical records from diabetic dogs assessed by the ophthalmology and the internal medicine services at the Veterinary Teaching Hospital of the Autonomous University of Barcelona were reviewed (2009-2019). Results: Seventy-five dogs (150 eyes) of both genders (51/75 females; 68% and 24/75 males; 32%) and a mean age of 9.37 ± 2.43 years, were included. The most common ocular findings were cataracts (146/150; 97.3%), vitreous degeneration (45/98; 45.9%), anterior uveitis (47/150; 31.3%), aqueous deficiency dry eye (ADDE) (33/150; 22%), diffuse corneal edema (31/150; 20.7%), non-proliferative retinopathy (13/98; 13.3%), and lipid keratopathy (9/150; 6%). The most prevalent type of cataracts observed (78/146; 53.4%) was intumescent, which was commonly accompanied by non-proliferative retinopathy (p = 0.003). Among the diabetic dogs, blood glucose levels were statistically higher in dogs with non-proliferative retinopathy or anterior uveitis (p < 0.005). Conclusions: Ocular complications of diabetes mellitus in dogs are numerous, being the most frequent intumescent cataracts, vitreous degeneration, anterior uveitis, ADDE, diffuse corneal edema, and non-proliferative retinopathy. This high prevalence warrants a more detailed ophthalmic evaluation in diabetic dogs especially for those undergoing cataract surgery. Furthermore, a predisposition for anterior segment inflammation and non-proliferative retinopathy is suggested when fasting plasma glucose is higher than 600 mg/dl..

Urrets-Zavalia syndrome following cataract surgery in dogs: A case series.

Background: In human medicine, Urrets-Zavalia syndrome (UZS) is a well-recognized but uncommon postoperative complication characterized by a fixed dilated pupil, accompanied by iris atrophy and glaucoma. Although it was originally reported in 1963 after penetrating keratoplasty surgery for keratoconus, it has been associated with various ophthalmic procedures such as cataract surgery. The condition has not been previously published in the veterinary literature. Case Description: Three client-owned diabetic dogs that developed UZS´s triad after cataract surgery are described. Despite uneventful phacoemulsification in the six eyes, five developed moderate-to-severe postoperative ocular hypertension. Although intraocular pressure (IOP) spikes were initially controlled, fixed dilated pupils accompanied by iris atrophy and chronic ocular hypertension were seen in the five affected eyes. Aggressive medical and surgical management maintained vision in three of those eyes. In one eye, uncontrolled IOP led to blindness. Conclusion: This is the first published description of UZS in dogs, occurring after phacoemulsification. Although no exact, demonstrable causative element could be determined, we believe that should be considered a triggering condition for this syndrome, as it directly affects the ocular blood flow autoregulation and intrinsic uveal tissue integrity. Until the contrary is proved, diabetes mellitus might be considered as a risk factor for developing this syndrome after cataract surgery in dogs.

Safety and efficacy of unilateral topical application of rocuronium bromide in healthy scops owls (Otus scops).

OBJECTIVE: To evaluate the safety and efficacy of unilateral topical application of rocuronium bromide in scops owls. ANIMALS STUDIED: Ten healthy adult scops owls. PROCEDURES: Birds weighting between 82-111 g were enrolled. Complete physical and ophthalmic examinations were performed. Each animal received a single dose of 0.15 mg of rocuronium bromide (30 µL) in a randomly selected eye. Static pupillometric evaluations were performed before and after drug instillation at 0, 30, 60, 90, and 120 minutes, in a room with fixed light intensity. Physical and ophthalmic examinations were carried out to evaluate possible adverse effects. RESULTS: Median pupil (95% CI) size at t0 was 7.10 mm (5.51-7.41) for placebo eyes and 7.22 mm (6.93-7.48) for treated eyes, showing no statistical differences (P > .05). When compared to the placebo eye, significant mydriasis was achieved at t30 [8.18 mm (7.22-9.00)] (P = .014) and lasting until t90 [7.35 mm (6.20-9.52)] (P = .004). Maximal mydriasis was obtained at t60 [8.63 mm (7.72-9.81)] (P = .001). During this period, the treated eye no longer responded to direct light stimulation. Complete mydriasis was observed in 5/10 birds (mean weight 97.4 g). Pupil size at t90 and t120 did not differ from baseline (P > .05) in treated eyes. No adverse effects were seen during the study period. CONCLUSION: Single-dose topical rocuronium bromide (0.15 mg) is a safe and effective medium duration mydriatic agent in scops owls. Further studies are needed to evaluate bilateral topical application and standardize the mydriatic protocol.

Intracanalicular injection of N-acetylcysteine as adjunctive treatment for sialoceles in dogs: 25 cases (2000-2017).

OBJECTIVE: To describe intracanalicular injection of 10% N-acetylcysteine (IINAC) as adjunctive treatment for sialoceles in dogs. ANIMALS: 25 client-owned dogs. PROCEDURES: Hard copy medical records at 2 veterinary ophthalmology practices were searched to identify dogs that underwent IINAC for treatment of sialoceles from January 2000 to December 2017. Signalment, affected salivary gland, clinical signs, duration of signs, other treatments administered, diagnostic tests performed, anesthetic approach, N-acetylcysteine volume administered, complications, follow-up time, and recurrence of sialoceles were recorded. Descriptive statistics were reported. RESULTS: Boxers and mixed-breed dogs were most commonly represented. Subjectively decreased globe retropulsion and conjunctival or periorbital swelling (23/25 [92%] dogs each) were the most common clinical signs, with no vision deficits in any patient. The zygomatic gland was mainly affected (23/25 [92%] dogs), followed by parotid and mandibular glands (1 [4%] dog each). The condition was unilateral in 22 (88%) dogs. Ultrasonography (19/25 [76%] dogs), MRI (14 [56%]), fine-needle aspiration (20 [80%]), and biopsy (4 [16%]) were performed; however, the condition was deemed idiopathic in 22 (88%) dogs. Most IINACs were performed with local anesthesia (median volume, 5 mL/gland; range, 1.5 to 9 mL). No complications were identified. Other treatments included antimicrobials and anti-inflammatories. Mean follow-up time was 18.8 months. All recurrences (5/23 [22%] dogs) were controlled with medical management. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested noninvasive IINAC may be a useful adjunctive treatment for sialoceles in dogs. The procedure was easily and safely performed with local anesthesia (or general anesthesia with concurrent diagnostic imaging) in these dogs.

Effects of topical 1% cyclopentolate hydrochloride on quantitative pupillometry measurements, tear production and intraocular pressure in healthy horses.

OBJECTIVE: To evaluate the effect of topical cyclopentolate hydrochloride (CH) on quantitative pupillometric readings (PR), tear production (TP), and intraocular pressure (IOP) in healthy horses. ANIMALS STUDIED: Fourteen client-owned horses. PROCEDURES: In a two-phase design study, each animal received 1% CH ophthalmic solution in the left eye [treated] and 0.9% NaCl in the right eye [control] (0.2 mL each). In the first phase (n = 7), TP, IOP, and PR assessment was performed by Schirmer tear test I, rebound tonometry and static pupillometry, at 1, 8, 24, 48, 72, 96, 120, 148, 172, and 196-hours post-instillation. In the second phase (n = 7), plateau mydriasis was evaluated by assessing PR hourly for 8 hours post-instillation. For PR assessment, pupil area (PA), vertical diameter (VPD), and horizontal diameter (HPD) were recorded. All pupillometries were obtained in a room with fixed light intensity (45-60 lux). Statistical analysis was performed by generalized estimating equations method for the effect on parameters over time. RESULTS: After topical CH, significant differences in pupil dilation were seen from 1 to 172 hours for VPD and from 8 to 24 hours for PA, without significant differences on HPD over time. In the second phase, plateau PA and VPD were reached at 3 hours, while plateau HPD at 2 hours. No significant effects were detected on TP and IOP in both eyes at any time, nor on PR of the nontreated eyes. CONCLUSIONS: Topical 1% cyclopentolate hydrochloride could be considered an effective and safe option when a mydriatic/cycloplegic drug is needed in horses.

Feline leishmaniosis: diagnosis, treatment and outcome in 16 cats.

OBJECTIVES: Leishmaniosis is a vector-borne disease and in European countries is caused by Leishmania infantum. Cats are considered secondary reservoirs of the infection in endemic areas. The objective of this retrospective study is to describe the clinical findings, diagnosis, treatment and outcome of feline leishmaniosis (FeL) in 16 cats in Spain. METHODS: Medical records of cats diagnosed with leishmaniosis were retrospectively reviewed for cases that met the following inclusion criteria: identification of Leishmania organisms and/or DNA on cytological and/or histological specimens and/or a high anti-Leishmania antibody titre, compatible clinical findings and pathological abnormalities. RESULTS: Sixteen cats met the inclusion criteria, all of which were living in areas endemic for canine leishmaniosis. Systemic signs were present in 11 cases (68.8%). The most common clinical signs on presentation included cutaneous lesions in 12 cats (75%), ocular disease in six cats (37.5%) and anorexia in six cats (37.5%). A polyclonal gammopathy was noted in 12 cats (85.7%). Non-regenerative anaemia and renal abnormalities were present in six (37.5%) and five patients (31.3%), respectively. In nine cats (56.3%), immunosuppressive conditions/comorbidities were identified. The diagnosis was made in eight of the cats (50%) by cytology, but a combination of diagnostic tests was needed for definitive diagnosis in the remaining patients. Twelve cats (75%) were treated specifically for leishmaniosis. Five of the 12 cats (41.7%) did not improve with treatment. The median survival time in the group of patients treated specifically for leishmaniosis was 17 months. Median survival of patients treated with concomitant diseases was 13 months vs 41 months in those without, although this was not statistically significant (P = 0.557). CONCLUSIONS AND RELEVANCE: Presentation of FeL appears to be similar to canine leishmaniosis but with some specific features: ulcerative and nodular skin lesions are the predominant cutaneous signs; cats with immunosuppressive conditions or coexisting diseases were more commonly present than typically seen in dogs (mainly feline immunodeficiency virus). A combination of diagnostic tests may be needed for definitive diagnosis.

Corneoconjunctival transposition for the treatment of deep stromal to full-thickness corneal defects in dogs: A multicentric retrospective study of 100 cases (2012-2018).

OBJECTIVE: To describe and evaluate the use of corneoconjunctival transposition (CTT) as a surgical treatment for canine deep stromal ulcers, descemetoceles, and full-thickness corneal defects and to determine its efficacy in preserving corneal graft transparency and vision. ANIMALS STUDIED: One hundred client-owned dogs with deep stromal ulcers, descemetoceles, or full-thickness corneal defects. METHODS: Medical records of canine patients that underwent CCT, from 2012 to 2018, were reviewed. Only, patients with preoperative positive consensual pupillary light and dazzle reflexes were included. RESULTS: There were 59 males and 41 females, from 0.3 to 17 years. Brachycephalic breeds were overrepresented (65%). All patients were unilaterally affected, with 16 deep stromal ulcers, 33 descemetoceles, and 51 corneal perforations, of a median (range) size of 4 (2-8) mm. The central cornea was affected in the majority of cases (57%), and euryblepharon and keratoconjunctivitis sicca were the most common concurrent ocular diseases (42% and 40%, respectively). The graft was most frequently harvested from dorsal (67%), and 9/0 absorbable suture material was used. Intraoperative and postoperative complications were seen in 7 and 21 cases, respectively. Mean follow-up time was 107.8 days. Vision was preserved in 96% patients, with 62% showing faint to mild opacification. Among the statistically analyzed variables, euryblepharon and pigmentary keratitis were found to be significantly associated with greater corneal graft opacification (P = .040 and P = .028, respectively). CONCLUSIONS: Corneoconjunctival transposition is an effective surgical treatment for deep stromal, descemetocele, and full-thickness corneal defects in dogs, achieving a highly satisfactory degree of corneal graft transparency and preserving vision.

A multicenter retrospective study on cryopreserved amniotic membrane transplantation for the treatment of complicated corneal ulcers in the dog.

OBJECTIVE: To describe the surgical technique and outcome of amniotic membrane transplantation (AMT) for treatment of complicated corneal ulcers in dogs. ANIMALS STUDIED: One hundred and eleven dogs. PROCEDURE: Medical records (2010-2017) were reviewed to identify canine patients that underwent AMT for the treatment of complicated corneal ulcers. Quantitative and ordinal variables were analyzed using Mann-Whitney U test and Fisher's Exact test. RESULTS: Brachycephalic breeds were overrepresented (74/111; 66.6%). Three dogs were bilaterally affected. Fifty-one had melting ulcers (51/114; 44.7%), 33 stromal ulcers (33/63; 52.4%), 17 descemetoceles (17/63; 27%), and 13 perforations (13/63;20.6%). Mean defect size was 6.2 mm (2-18 mm). Human (32/114; 28.1%) or bovine (82/114; 71.9%) (AmnioVet(R)) cryopreserved amniotic membranes were used. Monolayer (31/114; 27.2%), bilayer (44/114; 38.6%) or multilayer technique (39/114; 34.2%) was performed, being anchored to the limbus (52/114; 45.6%), to the defect (48/114; 42.1%) or both (14/114; 12.3%). Mean epithelial healing and follow-up times were 25.6 days (15-45) and 98.7 days (21-400), respectively. Most common postsurgical complications included pigmentation (10/114; 8.8%) and graft failure (5/114; 4.4%). Depth and size of corneal lesions, human amniotic membrane (AM) and concurrent ocular diseases were associated with more complications (P < 0.05). Good cosmetic and visual outcomes were achieved in 99.1% (113/114) and 97.4% (111/114) of cases, respectively. Zero to low graft opacity was seen in 23.9% of the eyes (27/113), mild to moderate in 64.6% (73/113) and complete in 11.5% (13/113). CONCLUSIONS: Cryopreserved AMT is an effective surgical technique for the treatment of complicated corneal ulcers in the dog, with highly satisfactory visual and cosmetic outcomes.

Ophthalmologic findings associated with Rhodococcus equi bronchopneumonia in foals.

OBJECTIVE: To describe ocular findings associated with Rhodococcus equi bronchopneumonia in foals, and to determine whether severity of the ocular lesions is related with outcome. ANIMALS STUDIED: Foals diagnosed with R equi infection at the VTH-UAB from January 2002 to December 2017. PROCEDURE: Rhodococcus equi infection was diagnosed by means of clinical signs, radiographic/ultrasonographic findings, and/or positive culture. In all the foals, a complete ophthalmic examination by a boarded ophthalmologist was performed and ocular signs were recorded and graded (0-4). RESULTS: Thirty-nine foals were included in the study, from which 12 showed signs of bilateral anterior uveitis (30.8%). Among these, three foals were classified as mildly uveitis-affected (MUA:7.7%) and nine as severely uveitis-affected (SUA:23.1%). Five SUA foals showed green aqueous flare (5/9;55.5%). Despite the systemic treatment, 9/39 sick foals died (23.1%), the fatality rate being different between groups: SUA (4/9;44.4%), MUA (0/3; 0%) and nonuveitis-affected foals (5/27;18.5%). Among SUA foals, only one with green aqueous flare died (1/5;20%). CONCLUSION: Bilateral anterior uveitis is highly prevalent in foals with R equi pneumonia (30.8%). The severity of anterior uveitis might be considered a nonsurvival prognostic factor and, until proven otherwise, green aqueous flare could be taken as a strongly suggestive ocular sign of the disease. Findings of this study remark the clinical relevance of performing a complete ophthalmic examination in sick foals, in order to help in the diagnosis and prognosis of uveal diseases, as well as to guaranteeing visual soundness.

Cryopreservation (-20°C) of equine corneoscleral tissue: Microbiological, histological, and ultrastructural study.

OBJECTIVE: To evaluate microbiological, histological, and ultrastructural characteristics of short-term cryopreserved (STC) equine corneoscleral tissue (<1 year), and to compare it with long-term cryopreserved (LTC) tissue (>7 years). ANIMALS STUDIED: Thirty-four healthy equine globes. PROCEDURE: After a decontamination protocol, globes were enucleated and stored at -20°C in broad-spectrum antibiotics. Corneoscleral tissue was evaluated at different storage periods: 1 month-1 year (20 eyes) and 7-9 years (12 eyes). Two eyes were used as controls. Microbiologic study included direct (blood, McConkey, and Sabouraud agars) and enrichment (brain-heart infusion broth) cultures. Cryopreservation artifacts were evaluated by hematoxylin-eosin. Corneoscleral collagen organization and number of normal and dead keratocytes were established by transmission electron microscopy. RESULTS: All microbiologic direct cultures were negative. Enrichment cultures were positive in 12.5% of corneal and 59.4% of scleral tissues (pcornea  = 0.136; psclera  = 1.000). Cryopreservation artifacts were most commonly observed in LTC tissues (P = 0.002). Normal keratocytes were predominant in STC corneas (STC 60% and LTC 0%) and apoptotic ones in LTC (STC 40% and LTC 90%), whereas necrotic keratocytes were only seen in LTC (LTC 10%) (P = 0.001). No structural differences were detected in collagen organization between STC and LTC (pcornea  = 1.000; psclera  = 0.703). CONCLUSIONS: Cryopreservation of equine corneoscleral tissue did not yield direct bacterial contamination. Apoptosis is the main cause of death of cryopreserved equine keratocytes. Based on the lack of significant structural differences between STC and LTC samples, these cryopreserved tissues could potentially be used for tectonic support for at least 9 years without structural or microbiological impediment.

Endothelial cell density and characterization of corneal endothelial cells in the Tawny Owl (Strix aluco) using specular microscopy.

OBJECTIVE: To determine endothelial cell density (ECD) and morphology and morphometry of corneal endothelial cells in the tawny owl (Strix aluco), as well as to report the effects of aging on these parameters. ANIMAL STUDY AND PROCEDURES: Twenty tawny owls were included in the study and classified into 2 groups according to their age: fledglings (<1 year old) and adults (>1 year old). Central corneal endothelium was studied by means of noncontact specular microscopy (Specular Microscope SP-2000P; Topcon, Tokyo, Japan), and results for ECD (cells/mm2 ), mean cell area ((MCA (µm2 )), polymegathism (CV), and pleomorphism (% hexagonal cells) were obtained. Results are described by median, interquartile range (25th, 75th percentiles), and absolute range for ECD, MCA, pleomorphism, and polymegathism. In addition, inferential analyses by Mann-Whitney U test were also performed. A two-tailed Type I error of 5% was established. RESULTS: Results in fledglings were as follows: ECD = 2864 cells/mm2 , MCA = 348 µm2 , % hexagonal cells = 72.75%, and CV = 21. Results in adults were as follows: ECD = 2602 cells/mm2 , MCA = 384 µm2 , % hexagonal cells = 78.83%, and CV = 16. No significant differences in ECD and MCA were seen between the groups (P > .05), although there were significant differences in % hexagonal cells and CV (P < .05). CONCLUSIONS: Tawny owls present a uniform endothelium in cell size and shape, although ECD and MCA differ greatly from other bird species. Differences in ECD and MCA could not be found between fledglings and adults probably because of the youth of adult specimens, although there were differences in pleomorphism and polymegathism.

Corneal thickness, endothelial cell density, and morphological and morphometric features of corneal endothelial cells in goats.

OBJECTIVE To determine corneal thickness (CT), endothelial cell density (ECD), and morphological and morphometric features of caprine eyes and to assess effects of aging on these variables. SAMPLE 27 healthy eyes of 19 Murciano-Granadina goats. PROCEDURES Goats were classified into 2 age groups (kids, 14 months old [14 eyes]; and adults, 7 to 10 years old [13 eyes]). The ECD and CT were calculated in the central cornea and 4 peripheral quadrants. Mean cell area (MCA), pleomorphism (percentage of hexagonal cells), and polymegathism were evaluated in the central cornea. RESULTS Median values for kids were determined for ECD (3,831 cells/mm2; inter-quartile [25th to 75th percentile] range [IQR], 3,669 to 4,011 cells/mm2), CT (608 µm; IQR, 573 to 655 µm), MCA (255 µm2; IQR, 243 to 272 µm2), pleomorphism (80.53%; IQR, 78.83% to 83.30%), and polymegathism (19; IQR, 18 to 22). Median values for adults were determined for ECD (2,101 cells/mm2; IQR, 1,966 to 2,251 cells/mm2), CT (706 µm; IQR, 670 to 730 µm), MCA (466 µm2; IQR, 425 to 507 µm2), pleomorphism (67.80%; IQR, 65.50% to 70.00%), and polymegathism (21; IQR, 15 to 26). Values differed significantly between the 2 groups for all variables, except polymegathism. For both groups, the dorsal and temporal quadrants were the thickest and thinnest, respectively. Ventral ECD was the lowest for both groups. CONCLUSIONS AND CLINICAL RELEVANCE ECD decreased with age, whereas MCA, pleomorphism, and CT increased. Moreover, differences among regions of the cornea indicated that the central cornea should not be considered as representative of the entire cornea.

A dose-escalation ex vivo study on the effects of intracameral benzalkonium chloride in rabbits.

BACKGROUND: Rabbits are currently not a good model for studying diseases of the corneal endothelium because their corneal endothelial cells (CECs) maintain a high proliferative capacity throughout almost all their life. Addressing this particular feature might allow the use of this species for such a purpose. The aim of this study was to evaluate the corneal endothelial injury after intracameral benzalkonium chloride (BAC) injection into rabbit eyes ex vivo, and to establish the most suitable starting dose for an in vivo study aimed at developing an animal model of corneal endothelial disease. RESULTS: Forty rabbit eyes obtained postmortem by transconjunctival enucleation were divided into 8 groups according to the injected compound: Control (no injection), BSS, and increasing BAC concentrations (0.005%, 0.01%, 0.025%, 0.05%, 0.1% and 0.2%). At 0, 6, 24 and 48 h, ophthalmologic examination of the anterior segment, pachymetry and specular microscopy were performed, and corneas were finally vital-stained and observed under the light microscope to assess the CECs morphology and mortality rate. When compared to BSS, CECs density started to decrease significantly at 0.025% BAC concentration, while mean cell area, corneal edema and corneal thickness began to increase significantly at 0.05%, 0.005% and 0.1% BAC concentrations, respectively. Concentrations of 0.05% BAC and above caused significant increases in CECs pleomorphism (decreased hexagonality) and mortality, compared to control and BSS. CONCLUSIONS: Ex vivo intracameral BAC injection induces corneal endothelial toxicity in rabbits. However, confirmatory in vivo studies are required to develop the desired model, with 0.05% BAC being a suggested starting point.

Modified brow suspension technique for the treatment of pseudoptosis due to redundant frontal skin in the dog: a retrospective study of 25 cases.

PURPOSE: To describe the outcome of modified brow suspension technique for the treatment of upper eyelid pseudoptosis in canine patients with redundant frontal skin folds. METHODS: Medical records from 1999 to 2015 were retrospectively reviewed. Only dogs that underwent modified brow suspension for treating bilateral pseudoptosis were included in the study. Recorded data included breed, age, gender, main ophthalmic complaint, ocular findings, suture material used for brow suspension, number of slings placed, postoperative treatment, complications, follow-up time, and outcome. RESULTS: Twenty-five adult dogs of different gender and breed fulfilled the inclusion criteria, with the Shar-Pei being overrepresented (19/25;76%). The main complaint at first presentation was mucopurulent discharge (10/25;40%) and blepharospasm (10/25;40%). Concurrent corneal disease was diagnosed in 47 eyes (47/50;94%). Monofilament polyamide was the most frequently used suture material (46/50;92%). Number of slings placed varied, with one in two eyes (4%), two in 28 eyes (56%), three in 17 eyes (34%), and four in three eyes (6%). Complications were seen in three eyes (6%): suture rupture (one eye; 2%) and skin abscess (two eyes; 4%). Mean follow-up time was 17.6 months (1-84 months), with no cases of fold dermatitis or dermatologic disease observed within this period. Good esthetic and functional outcomes were obtained in 47 eyes at first intervention (97%) and in all patients after re-intervention. CONCLUSIONS: The modified brow suspension technique described offers a surgical alternative for dogs with pseudoptosis secondary to redundant frontal skin folds that potentially reduces anesthetic time and facial changes.

Cryopreservation (-20 °C) of canine corneoscleral tissue: histological, microbiological, and ultrastructural study.

OBJECTIVE: To evaluate microbiological, histological, and ultrastructural characteristics of short-term cryopreserved (STC) canine corneoscleral tissue (<1 year) and to compare it with long-term cryopreserved (LTC) tissue (>6 years). ANIMALS STUDIED: Thirty-six healthy canine globes. PROCEDURE: After a decontamination protocol, globes were enucleated and stored at -20 °C. Corneoscleral tissue was evaluated at different periods: <1 year (20 eyes) and >6 years (12 eyes). Four eyes were used as controls. Microbiologic study included direct (blood, McConkey and Sabouraud agars) and enrichment (brain-heart infusion broth) cultures. Cryopreservation artifacts were evaluated by hematoxylin-eosin. Corneoscleral collagen organization and number of normal and dead keratocytes were established by transmission electron microscopy (TEM). Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) was also used for keratocyte characterization. RESULTS: Corneal microbial growth was observed in 25% of the direct STC cultures, and in 47.4% and 16.7% of the enriched STC and LTC cultures, respectively. Scleral STC direct cultures were 30% positive, while enrichment cultures were positive in 66.7% and 16.7% of the STC and LTC, respectively (P = 0.011). Cryopreservation artifacts were higher in LTC tissues (P < 0.001). Apoptotic keratocytes were predominant by TEM and TUNEL, in both STC and LTC. Minimal structural differences were detected in collagen organization between STC and LTC. CONCLUSIONS: Cryopreservation of canine corneoscleral tissue seems to reduce bacterial contamination over time. Apoptosis is the main way of death of cryopreserved canine keratocytes. Based on the lack of significant structural differences between STC and LTC samples, these cryopreserved tissues could potentially be used for tectonic support for at least 8 years without structural or microbiological impediment.

Corneal grafting for the treatment of full-thickness corneal defects in dogs: a review of 50 cases.

OBJECTIVE: To describe corneal grafting for the treatment of full-thickness corneal defects in dogs and to determine its effectiveness in preserving vision. METHODS: A review of the medical records of dogs that underwent corneal grafting following corneal perforations (≥3 mm) at the VTH-UAB from 2002 to 2012 was carried out. RESULTS: Fifty dogs of different breed, age and gender were included. Brachycephalic breeds were overrepresented (37/50;74%). All cases were unilateral, with euryblepharon being the most common concurrent ocular abnormality (20/50;40%). Full-thickness penetrating keratoplasties (FTPK) were performed in 21/50 eyes (42%) and lamellar keratoplasties (LK) in 29/50 eyes (58%). Frozen grafts (FroG) were used in 43/50 eyes (86%) and fresh homologous grafts (FreHoG) in 7/50 (14%). Of the former group, 26 were homologous (FroHoG:60%) and 17 heterologous (FroHeG:40%). A combination of topical medication (antibiotics, corticosteroids, cycloplegics, and 0.2% cyclosporine A) and systemic mycophenolate mofetil was administered. Median follow-up time was 200 days. Postsurgical complications included wound dehiscence (6/50;12%) and glaucoma (4/50;8%). Clinical signs of graft rejection were diagnosed as follows: FroHoG (13/26;50%), FroHeG (11/17;65%), FreHoG (4/7;57%), FTPK (12/21;57%), and LK (16/29;55%). Medical treatment successfully controlled graft rejection in 11/28 eyes (39%). Good anatomical outcome was achieved in 86% (43/50), of which 95% (41/43) were visual at last examination, with moderate opacification to complete transparency of the graft present in 48.2%. CONCLUSIONS: Corneal grafting is an effective surgical treatment for full-thickness corneal defects in dogs. If graft rejection is present, additional medical or surgical therapy may be necessary, achieving a highly satisfactory visual outcome.

A Swine Model of Selective Geographic Atrophy of Outer Retinal Layers Mimicking Atrophic AMD: A Phase I Escalating Dose of Subretinal Sodium Iodate.

PURPOSE: To establish the dose of subretinal sodium iodate (NaIO3) in order to create a toxin-induced large animal model of selective circumscribed atrophy of outer retinal layers, the retinal pigment epithelium (RPE), and photoreceptors, by spectral-domain optical coherence tomography (SD-OCT) and immunocytochemistry. METHODS: Fifteen male and female healthy Yorkshire pigs received unilateral subretinal escalating doses of NaIO3 under general anesthesia. In all the animals, volumes of 0.1 to 0.2 mL NaIO3 were injected into the subretinal space of the area centralis through a 23/38-gauge subretinal cannula. Control SD-OCTs were performed 1 and 2 months after the surgery, at which time pigs were euthanized and eyes enucleated. Globes were routinely processed for histologic and immunohistochemical evaluation. RESULTS: Spectral-domain OCT and immunohistochemistry revealed circumscribed and well-demarcated funduscopic lesions, limited to the outer retinal layers in pigs treated with 0.01 mg/mL subretinal sodium iodate. CONCLUSIONS: The swine model of a controlled area of circumscribed retinal damage, with well-delimited borders, and selectively of the outer layers of the retina presented herein shows several clinical and histologic features of geographic atrophy in AMD. Therefore, it may represent a valuable tool in the investigation of new emerging regenerative therapies that aim to restore visual function, such as stem cell transplantation or optogenetics.