[Cranial nerve functional neurosurgery: evaluation of surgical practice]. / La neurochirurgie fonctionnelle des nerfs crâniens Evaluation de l'activité

We report the results of an investigation carried out on the activity of functional neurosurgery of the cranial nerves in the French-speaking countries, based on the analysis of a questionnaire addressed to all the members of the SNCLF. Eighteen centers responded to this questionnaire, which showed that activities and indications varied greatly from one unit to another. The results appear homogeneous and comparable with those reported in the literature. The questionnaire sought to provide a global perspective, open to the comments and questions of all responders on the various techniques raised, with the objective of establishing a common decisional tree for these pathologies and providing if possible to a consensus for better dissemination of these therapies.

Anatomy of the orbit and its surgical approach.

A micro anatomical and surgical study of the orbit was conducted on cadaver specimens. First of all we reviewed the anatomy of the orbit with special emphasis on microanatomical structures. Three neurosurgical approches are then described with all structures encountered along these routes. The superior approach which provides a good access to the superior part of the orbit is the only route which can explore all parts of the optic nerve even in the optic canal. The lateral compartment of the orbit could be exposed by the lateral approach above or below the lateral rectus muscle. It is the only route that could give access to the inferior part of the orbit. The supero lateral approach is the largest route and has advantages of the two preceding routes. It gives access to the superior part of the orbit but not the optic canal and gives also a good exposition to the lateral part of the orbit but less than the lateral route in the inferior part. These approaches could be used to remove all intra orbital lesions apart from those located in the infero medial part of the orbit.

Surgical anatomy of calvarial skin and bones--with particular reference to neurosurgical approaches.

This chapter on surgical anatomy is addressed to young neurosurgeons and could be used as an introduction to basic neurosurgical technique. It aims to cover the basic anatomy relevant to making incisions in the scalp and creating bone flaps, an essential preliminary to any form of intracranial surgery. We will examine the anatomy of the scalp, its arterial and venous supply and its nervous system, as well as providing some technical points related to the cranial vault and the base of the skull. It will be explained how a well-grounded knowledge of the anatomical details makes it possible to execute correctly two of the most common approaches in neurosurgical practice, namely the pterional approach and an approach around the sinuso-jugular axis.

[Spinal repair of ventral root avulsions after brachial plexus injuries: Towards new surgical strategies?]. / Réparation médullaire des avulsions radiculaires du plexus brachial: vers de nouvelles stratégies chirurgicales?

BACKGROUND AND PURPOSE: Avulsion of nerve roots associated with the brachial plexus results in dramatic lesions with a prognosis which remains poor to this day. These lesions are considered as involving the central nervous system and therefore not amenable to surgical repair. However, the results of many experiments in animals have shown that if continuity can be re-established between the cervical cord and a denervated muscle or the distal end of its nerve, spinal motor neurons can regrow into a peripheral nerve graft, ultimately leading to the restoration of functional contraction. A preliminary experiment was attempted in humans but the outcomes were modest. In light of all the controversy raised by these preliminary results, we sought to demonstrate that axons can indeed regrow after intra-spinal re-implantation of an avulsed nerve root, that such re-growth can lead to the recovery of function, and that the phenomenon should be focused upon for the development of new surgical modalities to correct this serious condition. METHODS: We first studied the anatomy of the intradural compartment and developed a posterior approach to the brachial plexus for implantation in the ventrolateral aspect of the spinal cord. The fact that the white matter of the central nervous system is not propitious for axon re-growth led us to investigate the advantages of directly implanting the graft in the ventrolateral sulcus of the spinal cord in order that it might reach the anterior horn of the gray matter. In order to do this, we developed in the laboratory a direct surgical approach to the anterior horn, an approach which we subsequently used in patients with avulsion of multiple nerve roots at different levels. RESULTS AND CONCLUSIONS: Intraspinal re-implantation did not induce any neurological complications and co-contraction of different muscles was not observed in any of the patients. Partial re-innervation was obtained of the triceps, biceps and deltoid muscles, the exact pattern depending on the type of lesion and the type of graft. Treatment with neurotrophic factors represents a parallel line of research which might well help improve outcomes in spinal surgery to repair nerve root avulsion.

Anatomical basis of an original pedal approach to the great saphenous vein for surgery.

Varicose vein repair often necessitates a distal approach to the great saphenous vein (GSV). The classic method involves a medial pre-malleolar approach. We propose a more distal approach via the medial surface of the foot where there is a cutaneous landmark, which can be used to locate the GSV in a simple, reliable and reproducible fashion. In 20 cadaveric feet, we dissected out the GSV exploiting the above-mentioned cutaneous landmark. We then extended the dissection up as far as the medial pre-malleolar region (from where the GSV is classically approached) in order to be able to compare the diameter of the vein at the two different points (in the foot and in the pre-malleolar region). We also compared the cutaneous landmark with ultrasonographic location of the GSV in 22 feet of healthy subjects. Both dissections and ultrasound examinations demonstrated the reliability of the cutaneous landmark. Moreover, no significant difference was detected in the diameter of the GSV at the two different approach points. This original distal approach to the GSV requires only minor modifications of current practice for varicose veins surgical treatment.