ABSTRACT
Magnetic resonance imaging (MRI) of two pig brains was realized. The animals were placed in the stereotaxic conditions currently used in experiments. To allow the positioning of the animal in the MRI instrument, landmarks were previously traced on the snout of the pig. To avoid movements, animals were deeply anesthetized. MRI were taken in frontal, horizontal and sagittal directions. Afterwards, the brains of the pigs were frozen and cut into sections, frontal for one animal and sagittal for the other. Histologic and MR images were compared. The usefulness of this technique is discussed.
Subject(s)
Brain/anatomy & histology , Swine/anatomy & histology , Animals , Magnetic Resonance Imaging/methods , Stereotaxic TechniquesABSTRACT
An apparatus has been developed derived from the Horsley-Clarke principle. Specific requirement was to use large breeds of pigs from weaning to adult age (5 to 120 kg). The pig auditory canals are oblique; the measurement of the corresponding angles was achieved by means of two interconnected barrels, used afterwards to fix the ear-bars. The wide variability of the skull morphology led to the systematic use of ventriculography with a liquid of contrast. Consequently the pieces allowing the head fixation in the stereotaxic apparatus were designed to avoid any shadow on the brain area. As it was not always possible to localize the commissura anterior, the anterior border of the recessus preopticus was chosen to determine, together with the commissura posterior, the reference horizontal plane. The antero-posterior coordinates were counted from the anterior border of the commissura posterior. The methodology, which has been tested in a wide range of pigs, is discussed in relation with the methods used for other animal species.