0000000000732748
AUTHOR
Andrés López
showing 5 related works from this author
Blocs nerveux périphériques, paresthésies et injections intraneurales
2010
Resume Les fibres nerveuses, myelinisees ou non, sont disposees en faisceaux et entourees de plusieurs membranes l’endonerve, l’epinerve et la perinerve. La transmission de l’influx nerveux se fait de facon saltatoire d’un noeud de Ranvier a l’autre sur les fibres myelinisees et de facon continue sur les fibres non myelinisees. La compression ou le traumatisme d’un nerf produit une rafale de potentiels d’action que le patient interprete comme une paresthesie. Ce phenomene persiste tant que dure la lesion axonale. Les aiguilles a biseau court penetrent moins souvent la perinerve mais donne des lesions plus importantes dans ce cas. L’echoguidage montre que des injections intraneurales interfa…
Ultrastructure of Dural Lesions Produced in Lumbar Punctures
2014
During lumbar puncture, the insertion of a single-use, short-beveled spinal needle produces a “tent-like” effect. The dura-arachnoid lesions produced by this Quincke type of needles show a “crescent moon” shape resembling the letter “U” or “V” (similar to the lid of a can), with clean-cut edges. As the needle tip advances, the cut fragment is folded inwards, while all dural and arachnoid layers are entirely severed and the edges of the lesion are displaced inwardly. As soon as the spinal needle is withdrawn, the edges of the lesion tend to retract, owing to the viscoelastic properties of the affected dura mater.
Ultrastructure of Spinal Dura Mater
2014
Pia mater is the innermost of the three meningeal membranes, closely surrounding the brain, the spinal cord, and the portion of spinal nerve roots extending towards their exit across the dura mater. A cellular layer and a subpial compartment shape the structure of the pia mater. The cellular layer is made up of flat, overlapping pial cells with amorphous, fundamental substance interposed among them. The surface of the cellular plane appears smooth and bright under scanning electron microscopy (SEM). Transmission electron microscopy shows that the cellular component is about three to five pial cells thick at the medullary level and two to three cells thick at the level of the nerve roots. Th…
Catheters in Regional Anesthesia
2014
Anesthesiologists use different types of catheters in the performance of continuous regional anesthetic techniques such as epidural, subarachnoid, and paravertebral blocks, as well as peripheral nerve blocks.
Ultrastructure of Human Spinal Trabecular Arachnoid
2014
The arachnoid trabecular layer, located internally to the arachnoid layer, is composed of fibers that form the spider web–like trabecular structure found in the subarachnoid space and in the adventitial layer of blood vessels. The arachnoid trabeculae give shape to tubular structures (arachnoid sheaths) for each nerve root and for the spinal cord. Some of these arachnoid trabeculae extend to the pia mater. The trabecular arachnoid is an extremely fragile structure, which can easily be damaged. Because of its fragility, this membrane may be destroyed during dissection and manipulation, so that it is not frequently seen or systematically described. Trabecular arachnoid limits nerve root movem…