Sacrificing the internal carotid artery in infiltrating neck tumours: a study of four clinical cases.

Tumour infiltration of the carotid arteries, especially the common carotid artery (CCA) and the internal carotid artery (ICA), is a great challenge in maxillofacial surgery. Cases in which the malignant tumour and/or lymph node is stuck to the carotid artery, especially the ICA, have previously been considered inoperable. Four such cases, two with recurrent metastatic nodal neck masses encasing the ICA, one with aggressive fibromatosis, and one with a carotid body tumour, are described herein. Successful resection of the mass along with the ICA was performed in all cases after a positive balloon occlusion test. All patients made an uneventful recovery with no signs or symptoms of any neurological deficits. In addition, all of the patients were free of disease for the whole postoperative period of 18 months.

Submandibular approach for tracheal intubation in patients with panfacial fractures.

BACKGROUND: The oral route for tracheal intubation can interfere with some maxillofacial surgical procedures. At the same time, the nasal route can be contraindicated or impossible. Tracheostomy is the usual solution in these circumstances, but it carries a high incidence of complications. We tested the submandibular route for tracheal intubation as an alternative to tracheostomy in such situations. METHODS: The procedure was performed in 13 patients suffering from panfacial fractures associated with a fracture of skull base or a displaced nasal fracture, and in one patient with post-caustic burn scar affecting most of the face including the nose and requiring a full thickness skin flap surrounding the mouth. RESULTS: The technique was found easy and satisfactory for both the surgeon and the anaesthetist. It allowed uninterrupted surgical techniques and a secure airway. In six of the 13 patients, the submandibular tracheal tube was left in place for up to 44 h in the intensive care unit after the operation without complications or difficulties. Accidental dislodgement of the tube to the right main bronchus occurred in two patients while carrying out the procedure; it was rapidly detected and corrected. In another two patients, postoperative superficial infection occurred that responded well to local treatment. No other complications were encountered. CONCLUSIONS: Submandibular tracheal intubation is a simple and effective technique for upper airway management in some maxillofacial surgical patients when both oral and nasal tracheal intubations are not convenient.

Common mutations in the familial Mediterranean fever gene associate with rapid progression to disability in non-Ashkenazi Jewish multiple sclerosis patients.

Ancient founder mutations in the Mediterranean fever gene, MEFV, are associated with familial Mediterranean fever, a recessive, episodic, inflammatory disease. Since these mutations are reported to express with above normal levels of acute phase reactants in healthy heterozygotes we postulated that the heterozygous phenotype could aggravate the clinical expression of ongoing autoimmune diseases. This study evaluated progression to disability in relapsing-remitting multiple sclerosis (RR-MS) patients of non-Ashkenazi and Ashkenazi origin carrying an MEFV mutation, particularly the detrimental M694V, using the expanded disability status scale (EDSS). In the non-Ashkenazi patients group (n=48), carriers (n=17) presented with a two-fold higher fraction which reached EDSS=3.0 and 6.0 compared to noncarriers (n=31) despite a comparable mean of MS duration. The median time to reach EDSS=3.0 was 2 years in the carriers vs 10 years in noncarriers (P=0.007); The median time to reach EDSS=6.0 was 6 years vs 23 years, respectively (P=0.003). M694V heterozygous patients reached both EDSS milestones earlier than other patients. Progression to disability was not enhanced in Ashkenazi RR-MS carriers (n=12, noncarriers n=59). In conclusion, non-Asheknazi MS patients carrying one mutated MEFV gene, particularly M694V, expressed rapid progression to disability. The expressed mutation may increase inflammatory damage inflicted by autoimmune responses.

Strain differences in autotomy levels in mice: relation to spinal excitability.

The consequences of combined transection of the sciatic and femoral nerves were investigated in mice of the ICR and C3HEB strains. Whereas all the animals of the C3HEB strain showed very clear self mutilatory behavior of the denervated limb (autotomy) none of the ICR mice showed autotomy. Further tests, using the hot plate and tail flick methods, show that C3HEB mice were more sensitive to noxious thermal stimuli than ICR mice. Finally, spinalization at the lumbar level revealed a markedly higher level of spinal excitability in C3HEB mice as evident from a marked decrease in nociceptive thresholds in these animals. No such threshold decrease was observed in spinalized ICR mice. The results suggest that different levels of spinal excitability underlie the susceptibility for the emergence of autotomy in mice. It is proposed that such different levels of excitability may also underlie the susceptibility for the emergence of neuropathic pain.

The split rib bundle graft in mandibular reconstruction.

This article describes a modified technique for the use of free non-vascularized split ribs (bound together in the form of a tight bundle), to reconstruct different types of mandibular defects. Experience gained over the last 4 years in treating 38 patients with different pathological lesions is presented. The procedure, carried out simultaneously with bone resection proved to be highly effective in providing mesio-distal spanning of the defect, adequate mandibular height as well as bucco-lingual thickness. This technique utilizes the different theories of osteogenesis: (a) from the periosteal cells, (b) from the transplanted living osteocytes and from (c) stimulating host mesenchymal cells to form new bone by bone induction. The surgical technique, results and conclusions are presented in this report.

Specific modulation of sodium channels in mammalian nerve by monoclonal antibodies.

Monoclonal antibodies (mAbs) were generated against the sodium channels in the intact membrane of the eel electroplax. These antibodies bind to nodes of Ranvier, as indicated by immunofluorescence. When externally applied to rat nerve fibers one of these mAbs blocks impulse conduction. In voltage-clamp experiments, this mAb was found to attenuate sodium current amplitude without affecting the time course. The dose-response curve was very steep and had an ED50 of 133 nM. About half of the mAb effect was shown to be due to a shift, in the hyperpolarizing direction, of the steady-state sodium inactivation versus membrane potential curve. The remaining effect was voltage- and time-independent. This mAb had no effect on the potassium or leakage currents. The results indicate that on the external surface of the sodium channel, there are a number of antigenically similar determinants, which are functionally linked to specific elements of the sodium conductance system. These functionally related determinants were preserved through the course of evolution.

Monoclonal antibodies associated with sodium channel block nerve impulse and stain nodes of Ranvier.

Monoclonal antibodies were generated against native eel electroplax sodium channels in their natural membrane. These antibodies block nerve conduction in rat central (optic) and peripheral (sciatic) nerve. The antibody binding to eel electroplax membrane fragments and to rat brain synaptosomes can be modulated by neurotoxins. Thus it implies that active sites of the sodium channels are immunogenic in their natural membrane. Unlike the antibodies described in the past, our antibodies recognize antigenic determinants which are associated with the physiological activity of the channel and have been conserved through evolution.