RESUMO
BACKGROUND: It has been proposed that sildenafil citrate can increase ocular blood flow, and that this property can be used to treat ocular disorders that involve reflex vasoconstriction. This study therefore proposes to ascertain the vasodilator effect of the drug on retrobulbar circulation in healthy rabbits. For this matter rabbits treated with sildenafil citrate or saline solution had their intraocular pressure (IOP), mean arterial pressure (MAP), ocular perfusion pressure (OPP) and color Doppler imaging of the external ophthalmic artery measured prior to treatment and on days one (moment M1), seven (when M2), fourteen (moment M3), twenty-one (moment M4), and thirty (moment M5) of treatment. RESULTS: The MAP and OPP values of treated group were lower than those of control group at all times, and the mean values differed statistically at moments M1 (S = 71.52 mmHg, C = 84.76 mmHg, p = 0.0356) and M5 (S = 71.38 mmHg, C = 85.52 mmHg, p = 0.0252). The IOP and color Doppler values of the external ophthalmic artery did not differ between tested groups. CONCLUSIONS: The dose of 10 mg of sildenafil citrate administered to healthy rabbits causes systemic vasodilation and consequently lower values of MAP and OPP. However, it does not induce changes in IOP and retrobulbar hemodynamics identifiable by color Doppler assessment of the external ophthalmic artery.
Assuntos
Pressão Intraocular/efeitos dos fármacos , Artéria Oftálmica/efeitos dos fármacos , Citrato de Sildenafila/farmacologia , Ultrassonografia Doppler em Cores , Vasodilatadores/farmacologia , Animais , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Artéria Oftálmica/anatomia & histologia , Artéria Oftálmica/fisiologia , Coelhos , Distribuição Aleatória , Resistência Vascular/efeitos dos fármacosRESUMO
A longitudinal study was conducted to identify the morphological development of eyes and head of Jersey cattle at different ages. A total of 48 healthy Jersey cattle, 1 to 58 months of age, were included in the study. Ophthalmologic examinations were performed to identify healthy cattle to form the age groups: GI (1- to 11-month-old), GII (16- to 24-month-old) and GIII (25- to 58-month-old). The animals were physically restrained and examined by transcorneal ultrasound of both eyes; the axial length (AxL), corneal thickness (CO), lenticular thickness (L), depth of the anterior (AC) and vitreous (VC) chambers were evaluated. The cranial measurements obtained included the total, cranial, and nasal lengths and widths. Subsequently, the cephalic index (CI) was calculated. The AxL (GI: 2.83 cm; GII: 3.16 cm; GIII: 3.24 cm), AC (GI: 0.44 cm; GII: 0.53 cm; GIII: 0.53 cm), L (GI: 0.88 cm; GII: 1.01 cm; GIII: 1.04 cm) and VC (GI: 1.44 cm; GII: 1.55 cm; GIII: 1.59 cm) increased (p ≤ .001) according to age, but the CO (GI: 0.07 cm; GII: 0.08 cm; GIII: 0.08 cm) (p > .05) did not. The total length (GI: 30.83 cm; GII: 43.29 cm; GIII: 44.15 cm), cranial length (GI: 18.11 cm; GII: 23.82 cm; GIII: 22.69 cm), nasal length (GI: 12.72 cm; GII: 19.47 cm; GIII: 21.46 cm) and nasal width (GI: 26.22 cm; GII: 33.82 cm; GIII: 34.00 cm) increased (p < .001), and the CI (GI: 85.66 cm; GII: 78.15 cm; GIII: 77.02 cm) decreased (p < .001). The AxL correlated positively (p < .001) with the cranial length and width and negatively with the CI (p > .05). The ocular biometry of Jersey cattle correlates with their cranial measurements at different ages. With increasing age, the eyes and the head grow, establishing growth curves similar to those of other mammals.
Assuntos
Bovinos , Cefalometria , Animais , Estudos LongitudinaisRESUMO
O hemangiossarcoma é a neoplasia maligna originária do endotélio vascular. Os sítios primários mais comuns são baço, fígado, coração e pele, sendo considerado raro o acometimento da pálpebra e demais componentes oculares. Neste relato, descreve-se o caso de uma cadela da raça Boxer, de dez anos de idade, que apresentou aumento de volume, na borda livre da terceira pálpebra, de cor vermelho escuro. O tratamento de escolha foi a remoção cirúrgica e o diagnóstico de hemangiossarcoma foi confirmado ao exame histopatológico.(AU)
Hemangiosarcoma is malignant neoplasm originating from the vascular endothelium. The most common primary sites of this neoplasia are the spleen, liver, heart and skin. The involvement of the eyelid and other ocular components is unusual. In this report, we describe the case of a 10-year-old Boxer bitch who presented an increase in volume, at the free edge of the third eyelid, a deep red color. The mass was surgically removed and the diagnosis of hemangiossarcoma was confirmed by histopathological exam.(AU)
El hemangiosarcoma es una neoplasia maligna originada en el endotelio vascular, encontrado principalmente en el bazo, hígado, corazón y piel. Su presencia en párpados y otros componentes oculares es poco común. En este relato se describe el caso de una perra de la raza Boxer, de diez años, que presentó aumento de volumen, en el borde libre del tercer párpado, de color rojo oscuro. El tratamiento escogido fue la remoción quirúrgica y el diagnóstico de hemangiosarcoma fue confirmado por examen histopatológico.(AU)