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Purpose: A satisfactory clinical outcome in dental implant treatment relies on primary stability for immediate load bearing. While the geometric design of an implant contributes to mechanical stability, the nature of the implant surface itself is also critically important. Biomechanical and microcomputerized tomographic evaluation of implant osseointegration was performed to compare alternative structural, chemical and biochemical, and/or pharmaceutical surface treatments applied to an identical established implant design. Materials and Methods: Dental implants with the same geometry but with 6 different surface treatments were tested in vivo in a sheep model (pelvis). Peri-implant bone density and removal torque were compared at2, 4, and 8 weeks after implantation. Implant surfaces tested were: sandblasted and acid-etched titanium (Ti), sandblasted and etched zirconia, Ti coated with calcium phosphate (CaP), Ti modified via anodic plasma-chemical treatment (APC), bisphosphonatecoated Ti (Ti + Bisphos), and Ti coated with collagen containing chondroitin sulfate (CS). Results: All dental implants were well integrated at the time of sacrifice. There were no significant differences observed in peri-implant bone density between implant groups. After 8 weeks of healing, removal torque values for Ti, Ti + Cap, Ti + Bisphos, and Ti + collagen + CS were significantly higher than those for zirconia and Ti +APC. Conclusions: Whereas the sandblasted/acid-etched Ti implant can still be considered the reference standard surface for dental implants, functional surface modifications such as bisphosphonate or collagen coating seem to enhance early peri-implant bone formation and should be studied further. [ABSTRACT FROM AUTHOR]

In order to overcome the common local treatment failure of canine sinonasal tumours, integrated boost techniques were tried in the cobalt/orthovoltage era, but dismissed because of unacceptable early (acute) toxicity. Intriguingly, a recent calculation study of a simultaneously integrated boost (SIB) technique for sinonasal irradiation using intensity‐modulated radiation therapy (IMRT) predicted theoretical feasibility. In this prospective pilot study we applied a commonly used protocol of 10 × 4.2 Gy to the planning target volume (PTV) with a 20%‐SIB dose to the gross tumour volume (GTV). Our hypothesis expected this dose escalation to be clinically tolerable if applied with image‐guided IMRT. We included 9 dogs diagnosed with sinonasal tumours without local/distant metastases. For treatment planning, organs at risk were contoured according to strict anatomical guidelines. Planning volume extensions (GTV/CTV/PTV) were standardized to minimize interplanner variability. Treatments were applied with rigid patient positioning and verified daily with image guidance. After radiation therapy, we set focus on early ophthalmologic complications as well as mucosal and cutaneous toxicity. Early toxicity was evaluated at week 1, 2, 3, 8 and 12 after radiotherapy. Only mild ophthalmologic complications were found. Three patients (33%) had self‐limiting moderate to severe early toxicity (grade 3 mucositis) which was managed medically. No patient developed ulcerations/haemorrhage/necrosis of skin/mucosa. The SIB protocol applied with image‐guided IMRT to treat canine sinonasal tumours led to clinically acceptable side effects. The suspected increased tumour control probability and the risk of late toxicity with the used dose escalation of 20% has to be further investigated. [ABSTRACT FROM AUTHOR]

Introduction: The study aimed to describe clinical indications for eye enucleation and exenteration, the occurrence of complications and long-term outcome in cattle, and examine owners' attitude towards enucleation and exenteration and their satisfaction with the surgical outcome. Medical records from the two veterinary teaching hospitals in Switzerland were reviewed to identify cattle that underwent unilateral enucleation or exenteration between January 2013 and December 2020. Data extracted included medical history, ocular examination, clinical diagnosis, surgical procedure including anesthesia, suture material and pattern used, complications, and treatment thereof. Long-term follow-up was evaluated via national animal database inquiries to determine survival time and via owners' interviews with the use of a standardized questionnaire that included questions regarding the occurrence of complications and reason for culling, production performances and perceived quality of life after surgery, concerns, factors affecting the decision to proceed with surgery, and general satisfaction with the outcome. Descriptive statistics, Fisher's exact tests and unpaired t-test were used to summarize the data and assess association between variables. Association was considered significant if p < 0,05. Thirty-eight cases were identified, with a median age of 5 years. More than half of the cases (55,3 %) were diagnosed with non-neoplastic ocular lesions represented by severe trauma with loss of globe content, globe rupture with history of infectious keratoconjunctivitis or hypopyon, or congenital malformations. The remaining cases were diagnosed with neoplastic lesions, including ocular squamous cell carcinoma (OSCC), melanoma, or sarcoma. Complications following surgery were reported in 29 % of cases and included postoperative infection and recurrence of OSCC. There was no significant association between ocular diagnosis and the occurrence of postoperative complications or survival time. Surgery did not seem to influence the animals' postoperative production performance or the perceived quality of life. Most owners (92 %) were satisfied with the surgical outcome. The occurrence of postoperative complications leading to increased overall costs and culling was the main reason for lower owner satisfaction.

Sporadic occurrence of inherited eye disorders has been reported in cattle but so far pathogenic variants were found only for rare forms of cataract but not for retinopathies. The aim of this study was to characterize the phenotype and the genetic aetiology of a recessive form of congenital day-blindness observed in several cases of purebred Original Braunvieh cattle. Electroretinography in an affected calf revealed absent cone-mediated function, whereas the rods continue to function normally. Brain areas involved in vision were morphologically normal. When targeting cones by immunofluorescence, a decrease in cone number and an accumulation of beta subunits of cone cyclic-nucleotide gated channel (CNGB3) in the outer plexiform layer of affected animals was obvious. Achromatopsia is a monogenic Mendelian disease characterized by the loss of cone photoreceptor function resulting in day-blindness, total color-blindness, and decreased central visual acuity. After SNP genotyping and subsequent homozygosity mapping with twelve affected cattle, we performed whole-genome sequencing and variant calling of three cases. We identified a single missense variant in the bovine CNGB3 gene situated in a ~2.5 Mb homozygous genome region on chromosome 14 shared between all cases. All affected cattle were homozygous carriers of the p.Asp251Asn mutation that was predicted to be deleterious, affecting an evolutionary conserved residue. In conclusion, we have evidence for the occurrence of a breed-specific novel CNGB3 -related form of recessively inherited achromatopsia in Original Braunvieh cattle which we have designated OH1 showing an allele frequency of the deleterious allele of ~8%. The identification of carriers will enable selection against this inherited disorder. The studied cattle might serve as an animal model to further elucidate the function of CNGB3 in mammals.

Background: Equine sport agencies list steroids as prohibited substances for competing horses., Objectives: The objective of this study was to investigate if the controlled substances dexamethasone and prednisolone are detectable in equine serum and urine samples during and after treatment with eye drops and if this can generate a positive doping test., Study Design: Prospective cohort study., Methods: The study cohort included 11 horses. One eye of the horses was treated with either dexamethasone (Maxitrol ® 0.1%, n = 5 eyes) or prednisolone (Pred forte ® 1%, n = 6 eyes) eye drops 3 times daily for 14 days. Dexamethasone and prednisolone concentrations were determined in serum and urine at day 0 (negative control), 1, 7, 14, 15, 17 and 21 using liquid chromatography-tandem mass spectrometry. Blood samples were collected within 2 hours post application. Urine samples were collected during spontaneous urination., Results: All serum samples (range: 0.7-43 ng/mL, mean 2.1 ng/mL) and urine samples (range 1.2-5 ng/mL, mean 0.8 ng/mL) showed measurable amounts of dexamethasone during the course of treatment. Concentrations in both serum and urine samples were below limit of detection (LOD) 24 hours after the last dexamethasone treatment (day 15). All serum samples (range 1.1-32.5 ng/mL, mean 6.4 ng/mL) and urine samples (range 3.7-19 ng/mL, mean 4.6 ng/mL) were positive for prednisolone during treatment. Urine samples were below LOD on day 15; serum samples on day 21., Conclusions: Dexamethasone and prednisolone eye drops can induce detectable drug levels in serum and urine samples of horses after a 14-day treatment plan. This can lead to a positive doping result. All samples tested negative (below LOD of the analytical method) for dexamethasone one day and for prednisolone one week after treatment cessation., (© 2021 EVJ Ltd.)

Objective: This prospective pilot study was conducted to evaluate the outcome of a commercially available corneal stroma substitute, Acellular Porcine Corneal Stroma (APCS), in dogs undergoing penetrating keratoplasty (PK) to restore corneal integrity after having deep ulcers., Method: Five dogs (1 eye in each dog) underwent a PK using APCS (BioCorneaVet™) as a graft. The surgical procedure and peri- and postoperative treatment were standardized. All cases required a minimum 6 months follow-up. Ease of keratoprosthetic tissue handling, graft survival, anterior chamber stability, corneal opacity, neovascularization and re-epithelialization were noted. Presence of secondary uveitis was investigated., Results: BioCorneaVet™ was easy to handle and, at all-time points, provided adequate tectonic support. Graft survival was achieved in all 5 cases. A minimum follow-up period of 10 months was available for the five eyes (22 months maximum). Degree and area of corneal graft opacity progressively improved resulting in minimal to moderate loss of transparency in all cases but one, where it was severe. Neovascularization degree was most severe 0.5-1 month after surgery and fully resolved 4-6 months post-surgery. Re-epithelialization was complete in the majority of grafts in 1 month. Secondary uveitis was not detected at any time in 4 of 5 dogs., Conclusion: BioCorneaVet™ seems to be an effective graft for PK in the dog. In this case series, APCS was convenient to handle during surgery and provided excellent tectonic support. The material showed good tissue biocompatibility and resulted in the majority of cases in minimal to moderate graft opacity, that ameliorates with time., (© 2021 American College of Veterinary Ophthalmologists.)

Objective: Intraocular fibrin clots caused by severe uveitis can be a sight-threatening condition that needs to be resolved quickly and reliably. Intracameral injection of tissue-plasminogen activator (tPA) is commonly used to resolve intraocular fibrin. However, the drug does not reach fibrinolytic concentrations after topical application. Desmoteplase (DSPA) is a structurally similar but smaller fibrinolytic agent with a higher fibrin selectivity, a longer half-life, and better biocompatibility compared with tPA. This study was designed to evaluate the corneal and scleral permeability of DSPA in rabbits, pigs, dogs, horses, and humans ex vivo., Procedures: Corneal and scleral tissues (n = 5 per group) were inserted into Franz-type diffusion chambers and exposed to 1.4 mg/mL DSPA for 30 minutes. Drug concentrations on the receiver side were determined by liquid chromatography-tandem mass spectrometry., Results: Concentrations of DSPA after corneal and scleral permeation through fresh tissues ranged from 0.0 to 16.3 µg/mL and 0.0 to 11.4 µg/mL (rabbits), 0.3 to 5.6 µg/mL and 3.1 to 9.2 µg/mL (dogs), 2.1 to 14.9 µg/mL and 4 to 8.7 µg/mL (horses), and 0.6 to 3 µg/mL and 2.9 to 18.1 µg/mL (pigs), respectively. A concentration of 0.07-12.9 µg/mL DSPA was detectable after diffusion through tissue culture preserved human donor bank corneas (Table 1)., Conclusions: Desmoteplase has the ability to permeate both cornea and sclera ex vivo in all species tested. Implications of the ex vivo permeability of DSPA suggest that in vivo permeability may be possible, and if so, it could lead to a novel topical application for lysing fibrin., (© 2020 American College of Veterinary Ophthalmologists.)

Objective: To evaluate leptospiral antibody prevalence in 65 horses with ERU and compare outcome in 36 surgically treated eyes (2010-2015)., Procedures: Retrospective data analysis of horses with ERU (n = 65). C-value calculation with microagglutination assay titer (MAT) results for Leptospira spp. Evaluation of follow-up data after pars plana vitrectomy (PPV, n = 21 eyes) and suprachoroidal cyclosporine device implantation (SCDI, n = 15 eyes). Differences between groups were statistically analyzed using Fishers exact test, significance set at P < .05., Results: Positive leptospiral titers were found in 28/65 blood, 31/65 aqueous humor (AH), and 19/20 vitreal (post-PPV) samples. The most common intraocular serovars were Leptospira interrogans grippotyphosa, pomona, and bratislava. Intraocular antibody production was suspected in samples of 22 horses (c-values > 1). Mean follow-up of surgical cases was 3.8 years (PPV) and 3.4 years (SCDI). PPV was performed in 21 eyes with positive, SCDI in 15 eyes with negative leptospiral test results. Uveitis recurred less often after PPV (2/21) compared to SCDI (6/15, P = .04). Retinal detachment occurred after PPV only (5/21, SCDI 0/15, P = .06), whereas only SCDI-treated eyes were enucleated (PPV 0/21, SCDI 3/15, P = .06). Blindness or visual impairment was equally likely to occur in both treatment groups after surgery (PPV 7/21, SCDI 7/15, P = .5)., Conclusions: Leptospiral antibody prevalence is high in horses with ERU in Switzerland. Recurrence of uveitis is uncommon following PPV in the present study; an increased risk of retinal detachment exists. Enucleation is more often warranted in horses after SCDI in this study due to a higher uveitis recurrence., (© 2020 American College of Veterinary Ophthalmologists.)

Objective: To analyze D-dimer concentrations in aqueous humor (AH) of rabbit eyes under physiological conditions, after induction of fibrin clots, and following fibrinolytic therapy., Animals Studied: Prospective study measuring D-dimers in aqueous humor of rabbit eyes with induced fibrin clots (n = 44)., Procedures: Rabbits were purchased in two groups, which led to two temporally separated experimentation groups. Different treatment protocols were compared for their efficacy in fibrin reduction (slit-lamp examination, high-resolution ultrasound). AH was taken from left eyes before clot induction (baseline, day 1), 24 hours later after clot establishment/prior to drug administration (post-induction, day 2) and 48 hours after clot induction (post-treatment, day 3). An enzyme-linked immunosorbent assay (ELISA) was performed to measure intraocular D-dimer concentrations RESULTS: D-dimer concentrations were measurable in all samples. There were no differences in D-dimer levels across time points or treatments within the arrival groups. However, a significant difference in mean D-dimer levels was observed between the two arrival groups (group 1:3.1 µg/mL; group 2:6.1 µg/mL; P < .0001), which made a direct comparison of treatment groups impossible. Clinically, all eyes displayed fibrin clots in the anterior chamber and different treatment types led to significant differences in clot resolution (clot size reduction after intracameral treatment: 98%, topical treatment: 60%, no treatment: 40%)., Conclusion: D-dimers were identified in all AH samples of rabbits with large variability between samples. D-dimer levels were neither predictive for differences in induced fibrin formation nor for drug efficacy., (© 2019 American College of Veterinary Ophthalmologists.)

Corneal cross-linking should be considered as treatment option in Friesian horses with infectious keratitis and corneal dystrophy. Optical coherence tomography, giving information of corneal structure, can help for diagnosis and monitoring., Competing Interests: None declared., (© 2020 The Authors. Clinical Case Reports published by John Wiley & Sons Ltd.)

Purpose: Healthcare-associated infection (HAI) is a well-known problem in human medicine. The contamination of medical devices with pathogenic organisms is less studied in veterinary medicine. The purpose of this multicenter study was to evaluate the bacterial contamination of slit lamps throughout Europe and part of the United States. The efficacy of standard cleaning was additionally investigated., Methods: Samples from adjustment wheels of slit lamps were taken by different veterinary ophthalmologists and submitted for culture (n = 29). The efficacy of cleaning protocols was evaluated by taking a second sample after routine cleaning (n = 29). Sensitivity testing was performed for pathogenic bacteria using the minimum inhibitory concentration (MIC) or disc diffusion (Kirby-Bauer) method. Statistical analysis was performed using Fisher's exact test., Results: Seventeen of 29 slit lamps were contaminated before cleaning. The most frequently cultured bacteria were Staphylococcus spp. and coliform bacteria. Twelve of 29 slit lamps showed no bacterial growth before and after cleaning. There was a significant difference before and after cleaning (P = 0.0008), with only 4/29 contaminated samples after cleaning., Conclusion: Contamination with pathogenic bacterial species is frequent in slit lamps used by veterinary ophthalmologists. A risk of cross-contamination in clinical patients has to be considered. Routine cleaning reduces bacterial contamination significantly., (© 2019 American College of Veterinary Ophthalmologists.)

A 3-year-old French bulldog was presented to the ophthalmology service of the Vetsuisse Faculty, University of Zurich with a 3-day history of conjunctival swelling of the left eye (OS). Ophthalmologic examination revealed a moderate conjunctival hyperemia and chemosis. A migrating foreign body having entered the conjunctival fornix behind the nictitating membrane was suspected. Within the first 24 hours of medical management, OS developed a panuveitis and a scleral perforation was highly suspected. Ocular and orbital ultrasound as well as conventional magnetic resonance imaging (MRI) examinations failed to confirm the presence of a perforating foreign body. A High-Resolution MRI (HR-MRI) using a microscopy coil was then performed with findings consistent with a perforating and migrating foreign body. A grass awn of 12 mm length was surgically retrieved "ab externo" from its' point of entry into the sclera. To the best of our knowledge, HR-MRI has not yet been used to examine canine eyes. This case report supports the idea that orbital imaging can be greatly enhanced with the introduction of HR-MRI using microscopy coils with clinically relevant implications., (© 2019 American College of Veterinary Ophthalmologists.)

Objective: To screen a closed herd of the Old Kladruber Horses (OKH) for the prevalence of ocular disorders and report normal ocular variations., Animals Studied: Two hundred and sixty-one horses, 122 Old Kladruber Gray Horses, and 139 Old Kladruber Black Horses owned by the National Stud Farm Kladruby nad Labem, Czech Republic, were included in the study with signalment and pedigree information recorded., Procedures: Bilateral ocular examination of manually restrained horses was performed in a darkened environment by a single examiner (RA), using a portable slit-lamp biomicroscope, direct ophthalmoscope, and monocular indirect ophthalmoscopy using a Finnoff transilluminator and 20 D condensing lens. Fluorescein testing was performed when indicated., Results: The animal ages ranged from 3 months to 27 years (mean 7.82 years, median 6 years). The gender ratio (males:females) was 109:152. Ophthalmological abnormalities were found in 133 (50.96%) horses; with right and left eyes affected equally. The most common abnormalities were cataract formation (35 horses), iris hyperpigmentation (29 horses), alterations in corpora nigra size (26 horses), nonsenile vitreal degeneration (24 horses), linear keratopathy (11 horses), corneal stromal haze (nine horses) and corneal subepithelial punctate opacities (nine horses). The most frequent variations of normal ocular anatomy were posterior lenticular suture lines (222 horses), tapetal hypoplasia (95 horses) resulting in a multi-colored tapetal fundus (31 horses), nuclear sclerosis (48 horses), and senile vitreal degeneration (30 horses)., Conclusions: Ocular disorders were relatively common in OKH, but typically not vision threatening and not interfering with the quality of life., (© 2018 American College of Veterinary Ophthalmologists.)

Purpose: Desmoteplase (DSPA) was evaluated and compared with tissue plasminogen activator (t-PA) for its intraocular fibrinolytic effect and short-term toxicity in an in vivo study using rabbit eyes., Methods: Fibrin clots were induced in the anterior chamber of 44 rabbit eyes, and drug efficacy was measured by clot size reduction over 24 h. Topical DSPA eye drops (1.4 and 2 mg/mL) were compared with vehicle solution in a multiple-drop regimen in 8 animals per group. Intracameral injections of 0.6 μg DSPA (n = 14) and 25 μg t-PA (n = 14) were evaluated for their fibrinolytic efficacy. Animals were euthanized 24 h after drug application., Results: No significant differences were seen between topically treated DSPA and vehicle-treated animals. Intracameral t-PA had a higher fibrinolytic efficacy than DSPA at early time points, but no significant difference was seen between both groups at 24-h postapplication. Animals with t-PA treatment demonstrated significantly more side effects compared with DSPA-treated animals. DSPA showed no-to-mild side effects after topical and intracameral treatment. Histologically, no toxic effects were observed in any globe., Conclusions: DSPA is a promising drug with fewer side effects and similar fibrinolytic efficacy compared with t-PA 24 h after intracameral application in rabbit eyes at the tested concentration. Drug efficacy might be improved by increasing intracameral DSPA doses.

A 17-week-old crossbred finishing pig was presented for lameness of approximately one week. Clinical evaluation, including ophthalmologic examination, revealed ataxia, partial flaccid paresis of the pelvic limbs, skin lesions at feet and claws, and severely reduced vision/blindness. Both eyes had multiple persistent pupillary membranes (iris-to-iris and iris-to-lens) and hypermature cataracts. Histopathological examination of the eyes revealed microphthalmia, microphakia with cataract formation, myovascularised membrane in the vitreous, retinal detachment, and retinal dysplasia. Microscopic examination of tissues collected postmortem demonstrated nonsuppurative polioencephalomyelitis with the most prominent inflammatory lesions in the lumbar spinal cord. Subsequently, presumed Teschen/Talfan disease was confirmed by porcine teschovirus identification in the spinal cord using the reverse transcription-polymerase chain reaction (RT-PCR). To the authors' knowledge, this is the first case report describing in detail histopathological changes in the porcine congenital microphthalmic syndrome.

Objective: To evaluate the most common bacterial pathogens associated with septic keratitis in veterinary patients from Switzerland. The second objective was to analyze antibiotic susceptibility test results of the identified bacterial pathogens. The third objective was to evaluate potential breed predispositions to septic keratitis., Procedures: Two hundred and fifty-five cultures and antibiotic susceptibility reports from dogs, cats, and horses with septic keratitis that were presented to the University of Zurich Veterinary Medical Teaching Hospital between 2009 and 2013 were reviewed. Odds ratios for the risk of having a septic keratitis were estimated for all dog and cat breeds compared to the general nonbrachycephalic hospital population., Results: Ninety-six, 29, and 31 positive cultures were obtained from 89 canine, 28 feline, and 29 equine eyes, respectively. Repeat sampling accounted for the differences in numbers. Negative culture results were obtained in 50, 31, and 18 cases. Staphylococci and streptococci accounted for 66% of the isolates in dogs and 80% of the isolates in cats and horses. Staphylococcus spp. had a higher percentage of fluoroquinolone-resistant isolates compared to previous reports. Brachycephalic breeds had elevated odds ratios for the presence of septic keratitis., Conclusion: Identified bacterial pathogens and their prevalence as well as the elevated odds ratios for septic keratitis in brachycephalics are roughly consistent with previous studies. Based on systemic breakpoint data, resistance to commonly used topical antibiotics, including the second-generation fluoroquinolones, was found., (© 2017 American College of Veterinary Ophthalmologists.)

Objective: To compare the localization and distribution of two different anesthetic fluid volumes around equine cadaver eyes to determine an appropriate volume for a single sub-Tenon's injection in horses., Procedure: A single sub-Tenon's injection of 2% lidocaine was performed in 10 equine cadaver heads (20 eyes) using two different volumes (7 mL on one side and 10 mL on the opposite side). The posterior circular distribution of the anesthetic was quantified in sagittal, dorsal, and transverse MRI (T2W-TSE) sequences and evaluated independently by three board-certified radiologists. The distribution of the two fluid volumes was compared via a paired Student's t-test. The interobserver reliability was evaluated via a Kruskal-Wallis test., Results: Extension of the injection fluid was observed along the dorsal and temporal quadrants of the globe within the subconjunctival space, the anterior and posterior sub-Tenon's space, and into the muscle sheaths along the extraocular muscles. Accumulation of anesthetic fluid directly surrounding the optic nerve was detected in three of 20 cadaver eyes. Circular distribution of the 7 and 10 mL anesthetic volumes was not significantly different (P = 0.849). More retrograde leakage of the anesthetic was observed using the 10 mL volume. Evaluation of interobserver reliability revealed no significant differences between observers (P = 0.21-0.92)., Conclusions: Sub-Tenon's anesthesia can have potential as an alternative to retrobulbar anesthesia for ophthalmic surgeries in equines. A 7- to 10-mL injection volume should be appropriate based on the results of this study. The distribution of the anesthetic solution in live tissues, the clinical effects, and the potential for complications will have to be evaluated in vivo., (© 2016 American College of Veterinary Ophthalmologists.)