R. Wolfram-Gabel

The parapharyngeal adipose corpus : morphologic study

The parapharyngeal adipose corpus is a well limited adipose structure lying deep in the prestylian space, close to the lateral wall of the upper part of the pharynx. Macroscopic and microscopic anatomic sections were made and compared with CT and MR sectional imaging. The walls and contents of the parapharyngeal adipose corpus are described on the basis of anatomic sections and are symmetrically visualized by sectional imaging in the axial and coronal planes. A knowledge of its relations explains its role in imaging as an early marker of invasive tumoral processes. It is in continuity with the upper part of the buccal fat pad and presents the same functional characteristics of a gliding structure.

Investigation of the human bridging veins structure using optical microscopy

In this paper, we investigated the brain–sinus junction and especially the bridging veins linking these two organs. Two types of optical microscopy were used: conventional optical microscopy and digital microscopy. We used thin histological sections prepared from a human brain, and stained with Masson’s trichrome, hemalun and orcein. Finally we observed the path of the bridging vein inside the brain–skull interface. At smaller scales, wavy collagen fiber bundles were found and characterized inside the vein walls. Taking into account the orientations of the different sections with reference to frontal planes, we found that the bridging vein has a very complex geometry, which increases the difficulty to determine fiber orientations in its walls. Nevertheless, we found that collagen fiber bundles are mainly circumferentially oriented in the superior sagittal sinus walls. In this paper, we were able to characterize precisely the path of the bridging vein from the brain to the sinus, with different magnifications.

New findings on intermetacarpal fat pads: anatomy and imaging

Many studies have focused on the functional importance of the gliding structures of the hand. These structures are clinically important in reconstructive surgery and mechanically essential for an efficient hand grasp. The aims of this study were to first review the intermetacarpal space and then focus on its fatty tissue, the intermetacarpal fat pad. This study used dissections and histological analysis of fetal and adult hands and CT scans of adult hands. The intermetacarpal fat pads are well-defined adipose structures located between the heads of the second, third, fourth and fifth metacarpal bones. They are located in spaces defined by the palmar fascia and its deep expansions. These spaces are closed distally but open proximally into the tunnels surrounding the flexor tendons (Legueu and Juvara canals). The pads are composed of non-mobilizable fat; they protect the neurovascular pedicles of the fingers. They may act with the palmar skin to mitigate compressive and shear forces during gripping. Finally they may be involved in neurological symptoms if their size is increased by any trauma or inflammatory process.

Espaces rachidiens intracanalaires : de l’anatomie radiologique au diagnostic étiologique

The spinal canal is divided into epidural, subdural and subarachnoid spaces. Intraspinal processes should be correctly placed into their space of origin. MRI is the best imaging modality to achieve this task. Accurate determination of the space of origin routinely requires the acquisition of two different pulse sequences, typically T1W and T2W images, in two orthogonal planes, usually axial and sagittal. Simple imaging features can assist in determining the site of origin: changes to the epidural fat, compression or widening of subarachnoid spaces. The epidural space, bordered medially by dura, contains fat and vascular structures. The subdural space is a virtual space in between the dura and arachnoid membrane. The subarachnoid space is home to the CSF, spinal cord and nerve rootlets. An epidural process replaces the epidural fat, displaces the dura and narrows the subarachnoid space. A subarachnoid process widens the subarachnoid space and spares the epidural fat. Epidural processes usually are infectious or tumoral, either primary or secondary to spinal involvement. Subarachnoid processes include primary tumors, leptomeningeal metastases, arachnoiditis and hemorrhage. Nerve sheath tumors and meningiomas are the most frequent intradural extramedullary tumors.

NR-WP-66 Imagerie du nerf peripherique, de la morphologie a la fonction

Objectifs Rappeler l’aspect normal des nerfs peripheriques en echo-graphie et en IRM. Connaitre les nouvelles techniques d’exploration des nerfs peripheriques que sont la neurographie par IRM, l’imagerie en tenseur de diffusion, la tractographie et l’IRM apres injection de produit de contraste specifique (USPIO). Savoir reconnaitre une atteinte musculaire d’origine neurogene. Points cles Importants progres de l’imagerie des nerfs peripheriques venant completer la clinique et l’electrophysiologie. Mise en evidence d’anomalies de signal precoces du nerf lese en cas de degenerescence wallerienne sous la forme d’un hypersignal en neurographie T2, d’une modification de la fraction d’anisotropie et d’une prise de contraste. Interet de ces techniques d’imagerie dans le futur pour detecter de maniere non invasive les lesions du systeme nerveux peripherique.