RESUMO
Until recently intra- and extra-cranial vessels in dogs have been imaged using conventional X-ray or digital subtraction angiography. As both of these methods are surgically demanding and involve the use of complex equipment with potential risks for the animal, they are now mainly used in experimental work. In this study, a method for delineating the intra- and extra-cranial vessels of dogs using contrast-enhanced magnetic resonance angiography (CE-MRA) has been examined. The MR images were acquired on a 1.5-T scanner after a bolus injection of gadolinium contrast medium. CE-MRA showed most of the major intra- and extra-cranial arteries and veins as well as most venous sinuses and plexuses of the brain. Difficulties may arise in differentiating between minor arterial and venous vessels as well as in the measurement of vessel diameter. More frequent use of this diagnostic method in clinical cases will indicate whether MRA of the head and brain is of as much use in veterinary medicine as it has become in human medicine. There is certainly potential value in detecting rare conditions in animals such as aneurysms and vascular malformations, as well as in examining vessels feeding intracranial masses and the investigation of cerebrovascular accidents.