Effects of topical application of 0.4% oxybuprocaine hydrochloride ophthalmic solution and 1% ropivacaine hydrochloride on corneal sensitivity in rats.

The aim of the present study was to determine and compare the degree and duration of corneal anesthesia following topical application of 0.4% oxybuprocaine hydrochloride ophthalmic solution and 1% ropivacaine hydrochloride treatment in healthy rats. A randomized, blinded, crossover study was conducted on 20 healthy adult Wistar rats, following complete physical and ophthalmological examination. Baseline corneal touch threshold (CTT) was determined in the central corneal area of both eyes with a Cochet-Bonnet aesthesiometer, in mm filament length. Oxybuprocaine was randomly applied to one eye and 0.9% sterile sodium chloride solution was instilled into the contralateral eye. Subsequent CTT measurements were performed in both eyes 5 minutes after topical application and at 5-minute intervals thereafter for 75-minutes in the anesthetized eye. Following a 2-week washout period, this protocol was repeated with ropivacaine. Quantitative data were summarized as mean ± standard deviation, median and inter-quartile range (Q1-Q3). Repeated measures data were analyzed over time and between treatments using Friedman test and Wilcoxon signed-rank test with Bonferroni adjustment (p < 0.05). Baseline CTT values were 60 mm in all eyes. With oxybuprocaine, CTT values decreased significantly for 65 minutes (0-55 mm; p = 0.002) when compared with baseline; the maximal anesthetic effect (no blink response at 5 mm filament length) was maintained for up to 15 minutes (p < 0.0001). With ropivacaine, CTT values were significantly lower than baseline for 30 minutes (0-55 mm; p = 0.002), with a maximal anesthetic effect recorded at 5 minutes in 18 eyes (p < 0.0001). Oxybuprocaine induced a significantly lower CTT than ropivacaine (p = 0.002) from 10 to 65 minutes following topical application. Both anesthetic agents induced significant corneal anesthesia; however, oxybuprocaine provided a greater and longer anesthetic effect, making it more suitable for potentially painful ophthalmologic procedures

Gastric Smooth Muscle Hamartomas Mimicking Polyps in a Dog: A Case Description and a Review of the Literature

This report presents a case of two smooth muscle hamartomas of the stomach in a 10-year-old male Boxer. The clinical history of the animal was of chronic vomiting, weight loss, and intermittent gastric distension, and it died because of chronic and congestive heart failure. Gross, histology, and immunohistochemistry (IHC) exams were performed. On necropsy, in the pyloric region of the stomach, two closely related polypoid growths between 10 and 15 mm in diameter were identified. On the cut sections, both polyps presented white to gray color, with homogenous architecture and well-defined limits. The thickness of the submucosal layer was seen to be increased to 1 cm. No other gastric alterations were identified by the necropsy exam. Histologically, both masses growth consisted of hyperplastic glands lined by foveolar epithelium, arranged in a papillary or branching pattern, and supported by a core of well-vascularised and marked smooth muscle tissue interspersed between glands. No dysplastic cells and mitotic figures were observed in these lesions. Immunohistochemistry revealed a strong cytoplasm labelling for smooth muscle actin of the bundles around the mucosal glands. To our knowledge, this is the first report of smooth muscle hamartomas mimicking multiple gastric polyps in dogs