Search

Purpose: To assess the efficacy of 0.5% tropicamide applied after topical administration of 1.4% hydroxyethyl cellulose (HEC) or 1.2% hyaluronic acid (HA) at different time intervals. Methods: Eleven healthy Labrador retriever dogs were used. The study consisted of 7 trials in which pupil diameter (PD) was measured every 30 min for 7 h after drug administration. In trial 1, PD was measured after tropicamide application (control). In trials 2-7, PD was measured after treatment with tropicamide 10 s, 1 and 5 min after application of HEC or HA. Data were analyzed using analysis of variance and post hoc Holm-Sidak tests. Results: Maximal PD (mean ± standard deviation) was significantly greater (P < 0.001) in 5 of 6 experimental trials, with the greatest PD recorded when HEC was applied 1 min (12.2 ± 0.4 mm) and HA 10 s (12.3 ± 0.5 mm) before tropicamide, compared with 11.2 ± 0. 7 mm in control trial 1. PD >10 mm was maintained for 2.75-5 h in trials 2-7 and 2.25 h in trial 1 (P < 0.001). Area under the PD-time curve ranged from 61.9 to 71.3 ± 2.9 mm·hours in trials 2-7, significantly greater than 59.3 ± 1.8 mm·hours in control trial 1 (P ≤ 0.031). Conclusions: Tropicamide efficacy was enhanced by prior administration of a mucoadhesive polymer. Additional studies are needed to determine if HEC and HA of varying concentrations similarly extend and potentiate the effect of other topical ophthalmic drugs in canine eyes. [ABSTRACT FROM AUTHOR]

Purpose: Review octopus ocular anatomy and describe the histopathologic findings in three octopuses diagnosed with phakitis and retinitis. Animals: Two common octopuses (Octopus vulgaris) and one giant Pacific octopus (Enteroctopus dofleini) with a history of ophthalmic disease. Methods: A literature search was performed for the ocular anatomy section. Both eyes from all three octopuses, and two control eyes, were submitted for histopathologic evaluation. Hematoxylin and eosin stain was used for standard histopathologic evaluation; GMS stain was used to screen for fungi, gram stain for bacteria; and Fite's acid fast stain for acid fast bacteria. Results: Anatomically, the anterior chamber of the octopus has direct contact with ambient water due to an opening in the dorsal aspect of a pseudocornea. The octopus lens is divided into anterior and posterior segments. The anterior half is exposed to the environment through the opening into the anterior chamber. Neither part of the lens has a lens capsule. The retina is everted, unlike the inverted vertebrate retina, and consists of just two layers. Histopathology revealed inflammatory phakitis and retinitis of varying severity in all six eyes of the study animals. No intraocular infectious organisms were recognized but one common octopus eye had clusters of coccidian parasites, identified as Aggregata sp., in extraocular tissues and blood vessels. Conclusion: We describe inflammatory phakitis and retinitis in two species of octopuses. The underlying cause for the severe intraocular response may be direct intraocular infection, water quality, an ocular manifestation of a systemic disease, or natural senescence. [ABSTRACT FROM AUTHOR]

Purpose: To determine whether the order of intraocular pressure (IOP) measurement affects readings, regardless of which eye is measured first. Methods: Intraocular pressure was measured in 31 and 41 dogs using applanation and rebound tonometry, respectively. Initially, IOP was measured in the first (randomly chosen) eye (reading A), followed by measurement in the fellow eye (reading B), and a third (repeated) measurement in the first eye (reading C). After 15 minutes, measurements were repeated in reverse order (readings D ‐ F). Results: Applanation tonometry revealed significant differences between readings A & B (15.6 ± 2.3 and 14.8 ± 2.7 mm Hg, respectively, p =.02), A & C (15.6 ± 2.3 and 14.5 ± 2.4 mm Hg, respectively, p =.002), D & E (14.5 ± 2.3 and 13.7 ± 2.1 mm Hg, respectively, p =.02), D & F (14.5 ± 2.3 and 13.9 ± 1.9 mm Hg, respectively, p =.05), and A & E (15.6 ± 2.3 and 13.7 ± 2.1 mm Hg, respectively, p =.001). Rebound tonometry yielded similar results, with additional differences between B & C (19.1 ± 3.0 and 18.2 ± 2.4 mm Hg, respectively, p =.002) and E & F (18.7 ± 3.3 and 18.2 ± 3.3 mm Hg, respectively, p =.02). Conclusions: Intraocular pressure measured in the first eye, whether right or left, is higher than in the fellow eye. Repeated tonometry in the same visit could result in a significant IOP decrease, though the magnitude may not be clinically appreciable. [ABSTRACT FROM AUTHOR]

Objective Procedures Results Conclusions Investigate the tolerance, stability, and efficacy of topical 0.1% and 1% atropine in cats.Six cats underwent two trials separated by a 2‐week washout period. One drop of artificial tears was placed in one randomly selected eye (control), and one drop of either 0.1% atropine (Trial I) or 1% atropine (Trial II) was placed in the other eye. Immediate adverse effects were recorded for severity (0–3) and duration (seconds). Horizontal pupil diameter (HPD), pupillary light reflexes (PLRs), intraocular pressure (IOP), Schirmer tear test‐1 (STT‐1), and heart rate (HR) were monitored at baseline then 8 h post‐administration. PLRs were assessed for a total of 72 h. Stability was assessed weekly for 1 month in room temperature and refrigerated conditions, evaluating solution clarity, pH, and drug concentrations.Adverse effects had a significantly lower severity score and shorter duration with 0.1% versus 1% atropine (severity 1.2 ± 0.4 vs. 2.5 ± 0.5, p = .010; duration 107.5 ± 53.3 vs. 293.3 ± 106.5 s, p = .009). HPD was significantly greater than baseline measurements as early as 40 min for both atropine formulations. Pupils were non‐responsive for a significantly shorter duration with 0.1% versus 1% atropine (median 7 h vs. 47.5 h, p = .031). Compared with control eyes, IOP was significantly elevated by 1% atropine (p = .021) but not 0.1% atropine (p = .502). No significant differences were noted in STT‐1 and HR measurements. Both solutions were stable in room temperature and refrigerated conditions for 1 month.Diluted 0.1% atropine was stable and better tolerated by cats, offering a potential alternative to feline patients that experience adverse effects from topical 1% atropine. [ABSTRACT FROM AUTHOR]

Purpose: Review octopus ocular anatomy and describe the histopathologic findings in three octopuses diagnosed with phakitis and retinitis., Animals: Two common octopuses (Octopus vulgaris) and one giant Pacific octopus (Enteroctopus dofleini) with a history of ophthalmic disease., Methods: A literature search was performed for the ocular anatomy section. Both eyes from all three octopuses, and two control eyes, were submitted for histopathologic evaluation. Hematoxylin and eosin stain was used for standard histopathologic evaluation; GMS stain was used to screen for fungi, gram stain for bacteria; and Fite's acid fast stain for acid fast bacteria., Results: Anatomically, the anterior chamber of the octopus has direct contact with ambient water due to an opening in the dorsal aspect of a pseudocornea. The octopus lens is divided into anterior and posterior segments. The anterior half is exposed to the environment through the opening into the anterior chamber. Neither part of the lens has a lens capsule. The retina is everted, unlike the inverted vertebrate retina, and consists of just two layers. Histopathology revealed inflammatory phakitis and retinitis of varying severity in all six eyes of the study animals. No intraocular infectious organisms were recognized but one common octopus eye had clusters of coccidian parasites, identified as Aggregata sp., in extraocular tissues and blood vessels., Conclusion: We describe inflammatory phakitis and retinitis in two species of octopuses. The underlying cause for the severe intraocular response may be direct intraocular infection, water quality, an ocular manifestation of a systemic disease, or natural senescence., (© 2021 American College of Veterinary Ophthalmologists.)