PubMed HealthSearch

Biomedical subjects

G Gaist

Publications and source records attributed to G Gaist.

At least 19 recordsLinked to original sources

Spinal cavernous angioma: a rare cause of subarachnoid hemorrhage.

A case of cervical intrathecal extramedullary cavernous angioma is presented. The rarity of this lesion in comparison with the more frequent vertebral cavernous angiomas with secondary extension to the epidural space is emphasized. The special features of this case are noted: the acute clinical onset due to recurrent subarachnoid hemorrhages, the visualization only by means of magnetic resonance imaging, and the unusual cervical level. The most debated characteristics of these lesions and the relevant literature are summarized.

Female

Comparison of [3H]choline and D-[3H]aspartate efflux from guinea pig and human neocortex.

The outflow of [3H]choline ([3H]Ch) evoked by electrical field stimulation and the efflux of D-[3H]Asp induced by 35 mM KCl and 1-10 microM ouabain were studied in human and guinea pig cortical slices, kept under identical experimental conditions. [3H]Ch outflow was significantly lower whereas D-[3H]Asp efflux was significantly higher in humans than in guinea pigs. This suggests a different proportion of the two neuronal systems in these two species. Blockade of muscarinic autoreceptors with atropine increased, whereas stimulation of alpha 2 receptors with norepinephrine (NE) reduced, the evoked [3H]Ch outflow to the same extent in human and guinea pig cortical slices. Conversely, NE did not affect ouabain-induced D-[3H]Asp efflux, suggesting that an alpha 2-mediated control is not operative in the glutamatergic cortical structures. Desmethylimipramine, 2-5 microM, was able to increase [3H]Ch outflow through atropine-like mechanisms only in the human. This drug at 20-50 microM inhibited [3H]Ch and D-[3H]Asp efflux in both species, through mechanisms unrelated to its monoamine reuptake blocking properties. Thus, similarities and differences can be detected between humans and guinea pigs with regard to (a) the relative potency of the cholinergic and acidic amino acidergic signals and (b) the modulation of neurotransmitter outflow by drugs acting on auto- and the heteroreceptors.

Animals

Langerhans cell histiocytosis of the spine causing cord compression: case report.

A case of Langerhans cell histiocytosis of the spine causing myeloradiculopathy is reported. Almost complete regression of symptoms and signs was observed in the patient after surgical treatment and radiotherapy. The clinical and histological features of the disease are discussed. The literature dealing with the previously reported cases of spinal histiocytosis involving neural structures is reviewed.

Adult

Inhibitory effect of NMDA receptor activation on quisqualate-stimulated phosphatidylinositol turnover in the human cerebral cortex.

The effect of excitatory amino acids (EAA) on the phosphatidylinositol (PI) turnover in human cerebral cortical slices was investigated. Quisqualic acid (QA) and, to lesser extent, ibotenic acid (IBO) at 10(-5)-10(-3) M increased inositol phosphate (IP) accumulation. L-Glutamic acid (L-glu), kainic acid (KA), alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid and N-methyl-D-aspartic acid (NMDA) were ineffective. NMDA dose-dependently antagonized the QA facilitatory effect. Such inhibition was prevented by the NMDA receptor complex antagonists (+)-5-methyl-10,11-dihydro-5H-dibenzo[a, d]cyclohepten-5,10-imine (MK-801) and by 3[+/-)-2-carboxypiperazin-4-yl)propyl-1-phosphonic acid. The effect of IBO (but not that of QA) was greatly potentiated by MK-801. These data suggest that the EAA metabotropic receptor described in the rodent brain is also present in human cerebral cortex and is negatively modulated by the NMDA receptor.

Amino Acids

Benign arterial dissections of the posterior circulation.

Four young adults with spontaneous dissection of the vertebrobasilar system are reported. Clinically, two patients presented with subarachnoid hemorrhage and two with brain-stem ischemia. In two cases of ruptured arterial dissection of the posterior cerebral artery, angiography demonstrated fusiform and "sausage-like" dilatation of the involved vessel. In two cases of occlusive dissection of the basilar artery, angiography revealed the typical "string sign." All four patients were treated conservatively: three survive in good clinical condition and one remains disabled. Follow-up angiograms showed spontaneous healing of the lesion with return to an almost normal arterial configuration in two cases; residual narrowing corresponding to the dissection was the most notable finding in the other two. It is recommended that, in a subset of neurologically stable patients, angiographic monitoring is undertaken to assess the tendency for spontaneous repair before surgical intervention is planned.

Adult

Stereotactic mesencephalic tractotomy in the treatment of chronic cancer pain.

A report is given on indications and results of treatment of chronic cancer pain using stereotactic mesencephalic tractotomy (SMT), based on own experiences in 202 patients. Percutaneous cervical cordotomy for upper body pain syndromes has been abandoned and replaced by SMT. Operative mortality of SMT was less than 0.5%, and also its morbidity was low and usually transitory. Bilateral procedures may be performed with an interval of at least seven days. Early recurrences within one month (15%) are due to insufficient coagulation. Late pain recurrence occurred in 4% and may be due to either nervous system regeneration (sprouting) or transmission of pain by alternate secondary pathways.

Chronic Disease

Surgical treatment of syringomyelia: favorable results with syringosubarachnoid shunting.

The authors review the clinical course of 29 patients who underwent syringosubarachnoid shunting for syringomyelia. Twenty-two patients presented hindbrain-related syringomyelia; seven patients had non-hindbrain-related syringomyelia secondary to trauma (four cases) and to spinal arachnoiditis (three cases). The surgical technique is described in detail. All patients showed postoperative deflation or collapse of the syrinx at follow-up magnetic resonance imaging evaluation. Symptoms stabilized in 17 cases (59%); 9 cases (31%) showed improvement in the neurological function; 3 cases (10%) presented delayed neurological deterioration, probably owing to spinal cord ischemia.

Adolescent

Stereotactic biopsy and treatment of brain stem lesions: combined study of 33 cases (Bologna-Marseille).

Intraaxial brain stem tumours are rarely treated by open surgical technique. In Bologna and Marseille, 23 and 10 stereotactic biopsies respectively were performed in patients with brain stem mass lesions. The mortality due to biopsy was 3% (1 pat.); while the morbidity was temporary in 6 cases (18%) and permanent in one patient (3%). The approach to the brain stem was via a frontal burr hole. 7 times, after biopsy and histological diagnosis, radioisotope implant of the neoplasm was performed with 125I (iodine). From the histological diagnoses of the lesions the following was found: only 40% of the young patients had highly malignant tumours; 83% of the adults had neoplasms (not all of the malignant type), while 17% of the verified lesions were non-neoplastic. Since a diagnosis of the lesion nature is impossible with current neuroradiological means, the authors noting a variety of masses found in their experience, emphasize the importance of stereotactic biopsy, as a scarcely invasive method to give a precise diagnosis and a possible treatment.

Adolescent

Arachnoid cysts of the middle cranial fossa: experience with 77 cases treated surgically.

Arachnoid cysts of the middle cranial fossa (Sylvian cysts), represent the most common type of intracranial leptomeningeal malformation. Among the 102 intracranial arachnoid cysts operated on at the authors' institution from January 1970 to August 1986, the 77 cases (75%) located in the middle cranial fossa are reviewed. The higher incidence in the first two decades of life (51 cases) as well as the marked predilection for the male sex (60 cases) and the left hemisphere (55 cases) are confirmed in the authors' experience. As for clinical presentation cranial deformities, symptoms of raised intracranial pressure and epilepsy constituted the most frequent features. In 13 patients a complicating lesion was associated: subdural or intracystic haematomas in 7 cases, subdural hygromas in 4 cases and, extradural haematomas in 2 cases. Based on the appearance at CT scan and the results at CT cisternography the authors proposed a classification into three basic types of increasing severity and different pathophysiologic conditions. All the patients underwent craniotomy, excision of the cyst walls and perforation into the basal cisterns. There was one postoperative death (mortality rate of 1.3%) due to meningitis. The remaining clinical results were gratifying in all three types of lesion; on follow-up CT scans the cysts of type I. and II. exhibited a steady tendency to reduction or obliteration while cerebral reexpansion seemed less evident in the third, most severe, type. The authors compare and discuss the options of radical open surgery versus shunting procedures.

Adolescent

A prospective clinical and epidemiological study of head injuries in northern Italy: the Comune of Ravenna.

An analysis of all the head injuries occurring during one year within a well-defined geographical area was conducted in the region served by the Ravenna City Hospital in Northern Italy. This hospital does not have a neurosurgical service, so that patients suspected of having neurosurgical problems are transferred to the neurosurgical unit in Bologna, a distance of 65 Km (40 mi.). Of the 1468 head-injured patients seen in the emergency room, 644 (44%) were hospitalized, with an incidence of 372/10(5) pop/year) and were subjected to X-ray study of the skull (83%), EEG (64%), and CT scan (7.5%). 9 patients were transferred to the neurosurgical unit as emergencies on a clinical basis only, all were found to harbor cerebral lesions, and 7 were operated on. Of the patients hospitalized and subjected to CT scan in Ravenna, only one (0.17%) was found to have a lesion necessitating surgery. Mortality was 7.2% with 83% of these patients dying before admission. Three-month follow-up examination revealed the persistence of some symptoms in 20% of the 379 patients examined, but 91% had already returned to their previous occupation. Analysis of the risk factors present in the patients admitted to a non-specialized hospital seems to show that the presence of skull fracture, abnormal EEG, and alteration of the clinical condition constitute the indications for a CT scan, in order to detect the presence of intracranial lesions.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent

Skull fracture as a risk factor of intracranial complications in minor head injuries: a prospective CT study in a series of 98 adult patients.

Ninety eight patients admitted to hospital after a minor head injury were studied by CT. Forty seven patients had a skull fracture and 51 did not. Significantly more intracranial lesions were found in those with a fracture (16) that those without (3) (p less than 0.01). Nine of the patients with a skull fracture and positive CT were transferred to a neurosurgical department, where six underwent operation. Operation was not required in patients without a skull fracture. Head injured patients with a skull fracture should undergo CT scanning to enable early detection of an intracranial haematoma.

Adolescent

Distal ulnar neuropathy from carpal ganglia: a clinical and electrophysiological study.

The clinical and electrophysiological observations in two cases of distal ulnar neuropathy from carpal ganglia are reported. In the first case, the ganglion was compressing the ulnar nerve just proximal to its division; in the second case, the ganglion was compressing the deep branch of the ulnar nerve just at its origin. In both cases, both axonal degeneration and segmental demyelination were present. A clinical classification of the compression syndromes of the deep ulnar branch is proposed.

Adult

Stereotaxis and abnormal movements.

A series is presented of 106 patients with extrapyramidal syndromes treated by stereotaxy. The importance of preoperative screening to assure favorable results is stressed. Surgical contraindications are elderly patients with dementia and akinesia. Axial dystonia and spasmodic torticollis respond poorly to stereotaxy; and bilateral interventions should be avoided.

Humans