Tethered cord syndrome.

AIM: Tethered cord syndrome (TCS) is a stretch-induced disorder of the spinal cord. Tethering is due to an inelastic structure anchoring the caudal end of the spinal cord as a short and thick filum terminale. Spinal dysraphism is occasionally associated,but the etiological relationship between these disorders remain unclear. Other anomalies may be concurrently found as hydromielia and Arnold-Chiari malformation. METHODS: The authors analysed neuroradiological findings in 5 children and 9 patients of 20-24 years of age; there were four male and ten female. The criteria for inclusion were neurological disturbances (disorders!) localizable to the level of the conus and evidence for spinal dysraphism. The purpose of this study was to make the precise diagnosis and make also precise planning for therapy, conservative or surgical treatment. RESULTS: The age of diagnosis of TCS varies from under 1 year to 14 years and is very rarely as late as adulthood. TCS can present late and insidiously with progressive gait disturbances, atrophy of various muscle groups or the entire limb, loss of reflexes,loss of sensation in the sacral dermatomes, sphincter disturbances, gait abnormality and pain in the gluteal, perianal and other pelvic areas. The diagnosis involves standard X-RAY examination, CT and CT-Mielography but MRI is now a diagnostic method of choice. Surgical untethering of the cord is recommended. The associated pain responds best to surgical treatment; ambulation and bladder function may improve as well. CONCLUSIONS: However sphincter dysfunction often remains a permanent problem. Given the potential for rapid deterioration with incomplete neurological recovery, even prophilactic surgery seems advisable. The patient need to be followed up, if not operated upon.

2-thiouracil is a selective inhibitor of neuronal nitric oxide synthase antagonising tetrahydrobiopterin-dependent enzyme activation and dimerisation.

2-thiouracil (TU), an established antithyroid drug and melanoma-seeker, was found to selectively inhibit neuronal nitric oxide synthase (nNOS) in a competitive manner (K(i)=20 microM), being inactive on the other NOS isoforms. The drug apparently interfered with the substrate- and tetrahydrobiopterin (BH(4))-binding to the enzyme. It caused a 60% inhibition of H(2)O(2) production in the absence of L-arginine and BH(4), and antagonised BH(4)-induced dimerisation of nNOS, but did not affect cytochrome c reduction. These results open new perspectives in the understanding of the antithyroid action of TU and provide a new lead structure for the development of selective nNOS inhibitors to elucidate the interdependence of the substrate and pteridine sites and to modulate pathologically aberrant NO formation.

Small arterial anastomoses: experimental models applicable to microneurosurgical practice.

Four main models of vascular microsurgical anastomoses in rabbits are described with reference to revascularization procedures in man. Some technical expedients designed to improve the patency rate, are outlined. This preliminary report emphasizes the value of laboratory training to achieve successful results with microneurosurgical treatment of cerebral ischemia.

Kinking and coiling of the internal carotid artery: Clinical-statistical observations and surgical perspectives.

The incidence of kinking and coiling of the internal carotid artery in an unselected series of 1,010 angiographies is reported. The angiographies of patients with cerebrovascular insufficiency and those of patients with other brain diseases were separately reviewed. On the basis of a statistical comparison, the finding of kinks and coils appears significantly higher in "vascular" than in "non-vascular" patients. The greater difference concerns age subgroups up to 50 years. These data give support to the assumption that both kinking and coiling of the internal carotid artery may play a role in determining cerebral ischemic attacks. Surgical experience concerns a series of 19 patients operated by various corrective procedures, including resection of the internal carotid artery and end-to-end anastomosis. It is felt that surgery, performed in appropriately selected cases, can afford significant benefits to cerebrovascular patients, especially those presenting recurrent ischemic episodes.

Cerebral pan-angiography in rabbit. Technical note.

An open technique of cerebral four-vessel angiography via femoral artery "in vivo" of the rabbit is described. This method allows a good visualization of extracranial and intracranial circulation without direct damage to the cerebral vessels.

Ceftazidime in the treatment of infective complications of spinal cord lesions.

The use and the abuse of the antibiotics are certainly a subject of great concern, particularly for the increasing incidence of multiresistant bacteria. Since these resistant organisms may be sensitive to cephalosporin, we have tested the effectiveness of a new cephalosporin, ceftazidime, in the treatment of resistant infection in spinal cord injured patients. A randomized study of ceftazidime versus amikacin was carried out on twenty patients. The preliminary results are presented.

Valuation of some biological parameters in acute spinal cord trauma: experimental study in rabbits.

The authors investigated the formation of edema consequent to Spinal Cord Injury in rabbits. The goal of this project was to study the accumulation of Water, Sodium, Potassium and Ferrum in traumatized cords in the early time after the acute injury. To this aim a spinal cord trauma was induced in forty unselected animals using the weight-drop method; Water content was measured by wet and dry weight method; Sodium, Potassium and Ferrum content were measured by atomic absorbance spectrophotometry. These parameters were recorded at various time from the cord trauma (30 minutes up to 14 days). The results are presented and discussed with a particular view to the relationships between biological variation and time from the injury.

Spinal ossifying arachnoiditis. Case report.

A case of low dorsal spinal cord compression, due to ossifying arachnoiditis, is reported. Its relationship with a venous malformation overlying the dorsal surface of the spinal cord is mentioned. The literature is reviewed and possible etiopathogenetic factors favouring this rare condition are discussed in the light of few similar reports. The value of surgical treatment is stressed.

Giant serpentine aneurysms: a separate entity.

Giant intracranial aneurysms containing a tortuous vascular channel appear, to some extent, different from other giant aneurysms. Their particular features are outlined in the present report which concerns a case of a small fusiform aneurysm of the posterior temporal branch of the middle cerebral artery evolving over five years into a giant serpentine aneurysm. Successful and complete removal of this lesion was achieved.

Arteriovenous shunts between dural branches of the carotid artery and the cavernous sinus.

Three cases with dural arteriovenous shunts of the cavernous sinus are reported. The clinical signs usually were mild and included frontal headache, dilated conjunctival veins, exophthalmos, bruit, and oculomotor nerve palsy. Arterial contributions to the fistulae arose from meningeal branches of the internal and external carotid arteries. The precise diagnosis was made by selective angiography supplemented by subtraction and magnification techniques. The distal occlusion of the feeding arteries close to the shunt offers advantages when compared with conventional vessel ligation because of a more effective exclusion of vascular abnormalities from the circulation.

Pontine hematomas.

Pontine hematomas are very rare lesions that in the past were found at postmortem examination rather than diagnosed from the clinical presentation. The advent of computed tomography allowed more frequent identification of those lesions which has shown a more favorable prognosis than formerly thought. Three patients suffering from intrapontine hematomas, revealed by computed tomography, are discussed. The etiopathogenesis, location, and clinical features of this lesion are discussed in an attempt to establish general criteria from adequate management. All 3 patients (2 treated conservatively and 1 by surgical evacuation) had a successful outcome. Repeat CT scans gave evidence of resolution of this lesion in all patients.

Giant intracavernous carotid aneurysm treated by combined trapping and extra- intra-cranial bypass.

A case of a giant intracavernous carotid aneurysm, surgically treated by combined procedure of trapping and extra- intra-cranial arterial bypass, is reported. The authors reviewed the literature concerning the risks of immediate, early and late ischaemic complications related to carotid surgical occlusion. In agreement with other authors, the usefulness of extra- intra-cranial anastomosis in preventing cerebral ischaemia, in patients requiring surgical occlusion of main cerebral arteries, is suggested.

Computerized tomography in a calcified postoperative extradural cyst.

Extradural cysts resulting from dural/arachnoidal tears are unusual postoperative complications. A case of a calcified cyst is reported, emphasising its mechanism of formation, clinical significance and radiographic features. It is quite surprising today that the question should still arise as to whether computerized tomography is able to enrich the process of diagnosis, and if so in what circumstances.

Fibromuscular dysplasia of the basilar artery. Report of a case.

A case of fibromuscular dysplasia (FMD), mostly involving the basilar artery, associated with an intracranial aneurysm, is presented. Although the patient was symptomatic, the typical angiographic pattern is felt to be in this case an incidental finding. However the potential for FMD to produce severe neurological impairment is emphasized. The case is used as a basis for discussing shortly the incidence, the characteristic radiological appearance, the relationship with the presence of intracranial aneurysms and the therapeutic problems of FMD.

Transient "cerebellar" mutism in lesions of the mesencephalic-cerebellar region.

Four patients aged from 20 to 48 years with transient mutism are presented: 3 patients underwent surgery for midline tumours of the mesencephalic-cerebellar region (medulloblastoma in two cases and pinealoblastoma in one), at times attached to one or both lateral recesses of the IV ventricle. One patient was hospitalized and treated for brain-stem ischemia. All patients developed mutism 48 to 72 hours after surgery; in the patient with brain-stem softening mutism appeared 72 hours after admission. All the patients had unimpaired consciousness and no deficits of lower cranial nerves. Speech, always normal in the first hours after surgery, was regained after a period of 6-16 weeks. Various hypotheses for this speech disorder are analyzed.