Search

Background: There has not been a thoroughly reported study of the comparison between spectral domain-optical coherence tomography (SD-OCT) with both ultrasound biomicroscopy (UBM) and gonioscopy on the evaluation of the iridocorneal angle (ICA) in dogs. Objectives: To investigate the diagnostic value of SD-OCT for the early detection of narrowing ICA by comparing and assessing inter-device agreement in anterior chamber angle (ACA) measurements obtained by SD-OCT and UBM, and ICA evaluations by gonioscopy. Methods: A total of 28 eyes from 28 client-owned dogs with normal intraocular pressure were included for examination. The ACA and angle opening distance (AOD) were measured from the SD-OCT and UBM images, and gonioscopy images were analyzed using the ICA grade and ZibWest angle index. Results: The mean ACA and AOD for SD-OCT were 28.31° ± 5.37° and 658.42 ± 219.90 µm, and for UBM, 28.34° ± 5.82° and 859.29 ± 221.80 µm, respectively. The mean difference in ACA between the average values of SD-OCT and UBM measurements was 0.03° with a 95% limit of agreement (LoA) span of 16.2°, indicating positive agreement; that in AOD was 200.85 µm with a 95% LoA span of 1,110.95 µm, indicating poor agreement. The Pearson correlation coefficient of the ACA of SD-OCT and ZibWest indices of gonioscopy was 0.624, indicating strong agreement; that of UBM and gonioscopy was 0.43, indicating moderate agreement. Conclusions: SD-OCT is well tolerated by canine patients due to its non-contact method and might be an alternative option for early screening of ICA narrowing in clinical settings. [ABSTRACT FROM AUTHOR]

Two Shih-Tzu dogs with atopic dermatitis presented with delayed periocular dermatitis (PD) following the instillation of dorzolamide and dorzolamide/timolol combination eyedrops; the development of dermatologic signs took 94 and 104 d in cases 1 and 2, respectively. Hypersensitivity to anti-glaucoma eyedrops was highly suspected, and treatment was discontinued. Delayed PD was significantly relieved in cases 1 and 2, at days 155 and 64 after discontinuation, respectively. In this study, the clinical characteristics and progression of delayed PD were described to inform clinicians who may encounter this rare side effect. [ABSTRACT FROM AUTHOR]

This study was aimed to evaluate the prophylactic anti-glaucoma effect of topical 5% betaxolol (BTX) and 2% dorzolamide (DRZ) on the second eye in dogs with unilateral primary angle closure glaucoma (PACG). Medical records of 60 dogs with unilateral PACG who received prophylactic anti-glaucoma eyedrops in the second eye, from 2016 to 2021, were reviewed. The prophylactic effects of BTX were maintained on 28/60 (46.7%) eyes until last visit and BTX failure was observed on median 510 (range, 53-1,927) days in 32/60 (53.3%) eyes. After DRZ instillation in BTX failure eyes, the prophylactic effects were extended at median 610 (range, 157-2,270) days in 21/32 (65.6%) eyes. DRZ failure eyes (17/21, 81.0%) eyes required chemical ablation or surgical intervention due to uncontrolled intraocular pressure. The duration of prophylactic effects was decreased with aging (R2 = 0.334, p = 0.006). The predominant breeds were Shih-Tzu (41.9%) and American Cocker Spaniel (30.6%) with no significant differences in survival curves (p = 0.210). The average prophylactic effects of BTX persisted more than 1.5 year and could be selected the first prophylactic eye drop in unilateral PACG. Also, early surgical intervention should be considered in prophylactic medications failure cases. [ABSTRACT FROM AUTHOR]

Background: Dry eye disease (DED) cannot be diagnosed by a single test because it is a multifactorial disorder of the ocular surface. Although studies on various dry eye tests (DETs) in dogs have been reported, standard criteria have not been established except for the Schirmer tear test 1 (STT-1). Objectives: To establish reference values for DETs in dogs with normal STT-1 values (≥ 15 mm/min) and to analyze the correlation between DETs. Methods: The STT-1 was performed in 10 healthy Beagle dogs (20 eyes). After 20 min, interferometry (IF) for estimating the lipid layer thickness (LLT) of the tear film, tear meniscus height (TMH), non-invasive tear breakup time (NIBUT), and meibomian gland loss rate of the upper eyelid (MGLRU) and lower eyelid (MGLRL), were measured using an ocular surface analyzer. Results: Mean values for STT-1, TMH, and NIBUT were as follows: 21.7 ± 3.4 mm/min, 0.41 ± 0.21 mm, and 19.1 ± 9.5 sec, respectively. The most frequent LLT range, measured by IF, was 30-80 nm (11 eyes), followed by 80 nm (5 eyes) and 80-140 nm (4 eyes). MGLRU ≤ 25% was measured in 11 eyes and 26%-50% in 9 eyes; MGLRL ≤ 25% in 8 eyes and 26%-50% in 12 eyes. Besides positive correlation between TMH and NIBUT ( P = 0.038), there were no significant associations between DETs. Conclusions: Data obtained in this study provided normative references that could be useful for diagnosing DED and for further research into correlation between DETs in dogs with DED. [ABSTRACT FROM AUTHOR]

The purpose of this study was to develop effective dental hygiene chews for cats based on the anatomical features of the dentition and patterns of chewing motion. All cats were volunteered for dental prophylaxis followed by dental impressions using yellow stone and alginate under general anesthesia. Twenty parameters related to dentition were defined in order to compare dental impressions using digital caliper. For the chewing motion study, patterns of chewing motion were identified based on recordings made with a digital camera. Ten cats (4 domestic shorthairs, 2 Russian blues, 1 American shorthair, 1 Persian, 1 Turkish Angora, and 1 Devon Rex) were recruited for the study. The parameters related to teeth and oral size were similar among the studied cats. Chewing motion can be described as more of a guillotine-like motion rather than a crushing motion, with cats chewing 3-7 times before swallowing. The chewing pattern of cats involves shearing for a short period of time followed by immediate swallowing. Therefore, the overall size of the dental hygiene chew could be determined based on the measurement of the oral size for inducing chewing. The surface details of the dental hygiene chew could be designed for prevention and removal of dental calculus and plaque in cats considering the anatomical teeth parameters. Dental hygiene chews customized for cats considering the different anatomical features of their teeth might be effective for oral care. [ABSTRACT FROM AUTHOR]