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The concept of a topographical map of the corpus callosum (CC) has emerged from lesion studies in humans and from anatomical tracing investigations in other mammals. We conducted the first in vivo study aimed at outlining the topographical organization of the normal human CC, using non-invasive functional magnetic resonance imaging (fMRI). We tested cortical and callosal activation by the BOLD effect during simple sensory stimulation (tactile, gustatory and visual) and simple motor tasks in 38 volunteers. The axonal organization of callosal white matter was also studied in 16/38 subjects, using diffusion tensor imaging (DTI) and diffusion tensor tractography (DTT). Activation foci evoked by taste stimuli were detected in most subjects in the anterior part of the CC, those elicited by motor tasks lay in the central portion of the body of the CC, and those elicited by tactile stimulation of different body regions lay in the posterior part of the body. Activation foci evoked by visual stimulation were seen in the splenium of the CC. Callosal fibers interconnecting the primary cortical areas activated by taste stimulation, motor tasks, and tactile and visual stimuli were shown by DTT. Anatomical correlates of the BOLD activation foci were demonstrated in the CC, with fibers crossing it at the level of the genu, anterior and posterior body, and splenium, respectively. This study demonstrates for the first time that the functional topographical organization of the human CC can be explored by fMRI in vivo. Our findings may have clinical implications, especially for neurosurgical planning.

The purpose of this study was to evaluate the interest of MRI of excised human brains before traditional pathological examination. MRI was performed on 40 formalin fixed brain specimen; the brains were placed on tap water in a plastic box, and submitted to standard MRI, 3D FT volume acquisition and multislice SE T1, PD and T2 weighted. The results of 3D FT volume acquisition were used for multiplanar reconstruction of planes according to the direction of anatomical structures. Our experience demonstrate that preliminary MRI of excised brains is possible because it does not alternate the results of following standard pathological examinations; the dissection may be focused on the MRI demonstrated pathology. MRI allows to correlate the results of the pathological examination of a slice with the state of the whole brain. An interesting option is the use of this method for medico-legal purpose.

Several cases of intrasinus bony densities above pathological dental areas are reported. Common radiological features are outlined (pediculate implantation on the sinusal floor, cortical limits, acute or chronic dental infection). In one case, an histological examination performed at the opportunity of a sinusal operation pointed out osteomatous tissues.

Thirty-two subjects affected by various types of epilepsy have been studied as follows: 1) from the clinical point of view with careful case history or by direct observation of the seizures; 2) from the EEG point of view by means of prolonged recordings during wakefulness and nocturnal sleep or with pharmacological activations; 3) from a radiological point of view with standard skull radiography, air-encephalography (PNX), brain scanning and, when necessary, with cerebral angiography, mono or bilateral. Furthermore, all the patients underwent a CAT at least once; in the majority of cases this examination was repeated after administration of contrast medium. The following results were obtained by comparing the various examinations: 1) anatomo-elector-clinical correlation was present only in some cases; 2) only in patients with cerebral neoplasms was there proof of an agreement in site between EEG, CAT and PNX; 3) it was not possible to detect in a definite manner epileptic glial lesions with CAT; 4) the EEG analysis, when repeated several times with different methods of investigations, whoed epileptic foci in a higher number compared to the anatomical focal lesions proved by CAT; 5) compared with air-encephalography and morphological brain scanning, CAT usually pointed out a higher number of focal and/or diffused cerebral lesions with a higher degree of precision; viceversa cerebral angiography proved to be irreplaceable in cases where it was necessary to study possible circulatory alterations.