RESUMO
OBJECTIVE: To measure blood velocity parameters of the main detectable branch of the pectinis oculi artery and compare with values found in other arteries in other species to form a hypothesis of the function of the pecten oculi in birds. METHODS: Eleven American pekin ducks (Anas platyrhynchos domestica) without ocular diseases were examined with ocular Doppler ultrasonography. The pectinate artery resistive index (RI) and pulsatility index (PI) were calculated. RESULTS: The mean of RI and PI values resulted, respectively, in: left eye (0.43 ± 0.07; 0.58 ± 0.13), right eye (0.37 ± 0.09; 0.47 ± 0.14), and both eyes (0.40 ± 0.08; 0.53 ± 0.14). DISCUSSION: The low RI and PI values found in the main branch of the pectinis oculi artery compared with other arteries in other tissues suggest a high metabolic activity in the pecten oculi, and it could indicate a nutritional function and/or intraocular pressure regulation.
Assuntos
Artérias/fisiologia , Patos/fisiologia , Olho/irrigação sanguínea , Resistência Vascular/fisiologia , Animais , Velocidade do Fluxo Sanguíneo/fisiologia , Velocidade do Fluxo Sanguíneo/veterinária , Hemodinâmica/fisiologia , Pressão Intraocular/fisiologia , Estados UnidosRESUMO
OBJECTIVE: To evaluate endodontic paper point tear test (PPTT) in rabbits and compare changes in corneal touch threshold (CTT) induced by Schirmer tear test (STT) and PPTT. Normal corneal sensitivity recovery time after both tear tests was also measured. Also, mean PPTT and STT values were obtained. METHODS: Tear production of 20 eyes, from 10 rabbits, was evaluated using STT and the PPTT. Central corneal touch threshold was measured by a Cochet-Bonnet esthesiometer before any tear test was performed (zero time), immediately after the test (1 min), and consecutively at 6, 11, 16, and 26 min. Tests were conducted on three consecutive days: Day 1 - control condition, no tear tests performed only the CTT; Day 2 - CTT before and after PPTT; and Day 3 - CTT before and after STT. CTT values were compared using repeated measures ANOVA. RESULTS: Corneal touch threshold was significantly increased for at least 16 min after STT, indicating STT causes corneal discomfort. No difference was found between CTT following PPTT and controls, indicating PPTT caused minimal corneal discomfort. The mean (±SD) value for STT was 5.2 ± 1.0 mm/min and for PPTT was 13.8 ± 1.5 mm/min. DISCUSSION: The aqueous fraction of rabbit's tears can be successfully measured by PPTT. This report established reference values for PPTT in rabbits. Additionally, the absence of a significant difference in CTT after PPTT compared with controls shows that PPTT is well tolerated by rabbits. Considering the improved comfort (compared with STT), accuracy, and low cost, PPTT is a bona fide method of measuring aqueous tear production in rabbits.
Assuntos
Córnea/fisiologia , Técnicas de Diagnóstico Oftalmológico/veterinária , Coelhos/fisiologia , Lágrimas/fisiologia , Animais , Corantes , Aparelho Lacrimal/metabolismo , Fenolsulfonaftaleína , Fitas ReagentesRESUMO
PURPOSE: To perform a descriptive investigation of the red-eared slider turtle (Trachemys scripta elegans) eye, performing selected ophthalmic diagnostic tests with the aim of establishing normal reference values for this species. METHOD: Thirty adult healthy red-eared slider turtles were used to establish normal ophthalmic test values in this investigation. Selected ophthalmic tests included: collection of material for bacterial culture analysis, esthesiometry, intraocular pressure (IOP), A- and B-mode ultrasonic biometry, fundus photography, and central corneal thickness (CCT). RESULTS AND DISCUSSION: Normal parameters found for the ocular diagnostic tests were: esthesiometry: 5.84 ± 0.48 cm; IOP: 5.42 ± 1.70 mmHg; CCT: 154.5 ± 0.14 µm; palpebral fissure length: 9.71 ± 0.55 mm; modified Schirmer tear test: 2.55 ± 3.4 mm; globe axial length: 7.60 ± 0.23 mm; anterior chamber depth: 0.76 ± 0.23 mm; lens axial length: 2.45 ± 0.28 mm; vitreous chamber depth: 4.31 ± 0.42 mm. An avascular retinal pattern with nerve fibers radiating from the small white circular optic disk was observed. None of the animals had a conus papillaris. The most frequent bacteria found were Bacillus spp. (33.33%) followed by Proteus vulgaris (20.69%) and Staphylococcus aureus (18.39%). No significant differences between left and right eyes or genders were found for any of the results. Reference data and morphologic observations obtained in this investigation might help veterinary ophthalmologists to diagnose ocular diseases in the red-eared slider turtle.
Assuntos
Técnicas de Diagnóstico Oftalmológico/veterinária , Olho/anatomia & histologia , Tartarugas/anatomia & histologia , Animais , Feminino , Masculino , Valores de ReferênciaRESUMO
OBJECTIVE: This investigation characterizes the occurrence of oculocardiac reflex (OCR) in conscious rabbits and dogs by observing the effect of an ocular compression stimulus on heart rate (HR). ANIMALS STUDIED: Thirty-four clinically healthy adult rabbits and 15 clinically healthy adult Beagle dogs were studied. PROCEDURES: An electrocardiogram was used to record the heart rhythm and HR continuously. Digital pressure was exerted over the eyelid on right eye, left eye and both eyes together for 1 min, with one-minute intervals between each compression. Variations in HR were observed in each minute by counting complexes on the electrocardiographs. RESULTS: There were no differences in HR between stages without ocular compressions both in dogs and in rabbits. HR reduction caused by ocular compression was statistically significant in rabbits only when both eyes were compressed in contrast with all stages without compression. In dogs, a statistically significant reduction in HR was seen during compression of just the right eye or the left eye compared with the baseline HR, and when both the right and left eyes were compressed together compared with baseline or after compression of the right eye. In dogs, compression of individual eyes produced a change similar to that seen during compression of both eyes. CONCLUSIONS: This study shows that OCR can occur during experimental ocular compression in conscious rabbits and Beagle dogs and characterizes the reduction in HR. Knowledge of this physiological response is important for veterinary anesthetists and ophthalmologists during ophthalmic surgery or eye manipulations.