Comparison of a rebound and an applanation tonometer for measuring intraocular pressure in normal rabbits.

OBJECTIVE: To compare intraocular pressure (IOP) measurements made on healthy adult rabbits without the effect of tranquilizers using the new applanation tonometer, Tono-Pen Avia(®), and the rebound tonometer Tonovet(®). METHODS: Intraocular pressure was measured throughout the day (6:00, 9:00, 12:00, 15:00, and 18:00 h) in 38 adult New Zealand White rabbits (76 eyes). The animals were 20 males and 18 females, with a mean weight of 3.5 kg and an average age of 6 months. A complete ocular exam (including Schirmer tear test, fluorescein staining, slit-lamp biomicroscopy, and direct ophthalmoscopy) was performed on all animals at the beginning of the trial. Rebound tonometry was performed, and after 10 min, anesthetic drops were instilled and applanation tonometry was carried out. IOP values obtained using the two techniques were analyzed statistically. RESULTS: The mean IOP was 9.51 ± 2.62 mmHg with Tonovet(®), and 15.44 ± 2.16 mmHg with the Tono-Pen Avia(®). Significant differences between measurements with the two tonometers were observed (P < 0.001). The linear regression equation describing the relationship between the two tonometers was y = 0.4923x + 10.754 (y = Tonovet(®) and x = Tono-Pen Avia(®)). High IOPs were recorded in the early measurements (6:00), but the average IOPs from both devices were statistically similar throughout the day (P = 0.086). The correlation coefficient was r(2) = 0.357. No significant difference in IOP regarding gender was observed. CONCLUSION: The Tono-Pen Avia(®) recorded higher levels of IOP compared with the Tonovet(®). Early in the day, the IOP of rabbits was higher than later in the day, regardless of the tonometer used.

Mionecrose aguda por Clostridium septicum em equinos / Acute myonecrosis by Clostridium septicum in horses

Descrevem-se dois casos de miosite necrosante causada por Clostridium septicum em equinos. Os dois equinos apresentavam aumento de volume no membro pélvico direito e que se estendia para a região abdominal ventral. Ao corte, essa área era formada por edema sanguinolento e bolhas de gás. Os músculos esqueléticos da região caudal da coxa apresentavam áreas vermelho-escuras, crepitantes, com edema sanguinolento e, ao corte, as áreas mais profundas da musculatura tinham aspecto seco. As principais alterações histopatológicas observadas foram tumefação, vacuolização, necrose hialina e necrose flocular de fibras musculares esqueléticas. Entre as fibras, havia hemorragia, edema e grande quantidade de bacilos com tamanho de 3-6μm. Na coloração de Gram, os bacilos se apresentavam roxos (gram-positivos); quando impregnados pela prata (Warthin-Starry), se mostraram enegrecidos. Nos dois casos, C. septicum foi isolado, em ambiente anaeróbio, do líquido de edema das lesões musculares.

Two cases of acute necrotizing myositis caused by Clostridium septicum in horses are described. Both horses presented swelling of the right pelvic limb extending to the ventral abdominal region. The cut surface of the affected area revealed blood-stained edema and gas bubbles. The skeletal muscles of the caudal region of the thigh of the affect limbs had dark red discolored areas of blood-stained edema and crepitation; the deep musculature was dry. The main histopathological findings were swelling, vacuolation and hyaline and floccular necrosis of skeletal myofibers; in between myofibers there were hemorrhage, edema and large amounts of bacilli. In both cases, C. septicum was isolated from the edema fluid of muscular lesions.