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Biomedical subjects

A Gaston

Publications and source records attributed to A Gaston.

At least 37 records · Page 2Linked to original sources
PubMed1996

Long-term outcome of unilaterally transplanted parkinsonian patients. I. Clinical approach.

Five patients with Parkinson's disease, unilaterally transplanted with foetal mesencephalic cells into putamen (n=1) or putamen and caudate (n=4), were followed throughout a period of 15-36 months after surgery, according to the recommendations of the core assessment programme for intracerebral transplantations (CAPIT). All these patients exhibited an increase in the fluorodopa uptake in the grafted putamen, which was most significant in the first and last patient of the series. Long-term bilateral improvement of skilled hand movements was observed, starting between the third and sixth month after grafting, and confirmed by the statistical analysis of CAPIT timed tests. A mild to moderate effect on the amount of 'off' time and 'on-off' fluctuations was observed, whereas, apart from one case, no other clear effect on gait, walking and speech was found. One patient included in the study, already suffering slight cognitive impairment, clearly exhibited progression of a dementia process after surgery. Daily living activities were clearly improved in only one of the other four patients. At the end of the study period, all patients needed L-dopa therapy at a similar or higher dose than before grafting, but, in most of them, other dopaminergic drugs were reduced or stopped. All patients exhibited bilateral dyskinesias before grafting that were greatly decreased in intensity a few months after surgery. Delayed asymmetrical dyskinesias, occurring on the side displaying the better motor improvement, i.e. contralateral to the graft, were observed in three patients. These results suggest that neural transplants may influence two central mechanisms involved in motor function and the onset of dyskinesias. These effects are likely to occur through complex interactions with the post-synaptic dopaminergic receptors. The occurrence of dyskinesias might simply reflect increased presynaptic storage and release of dopamine. Alternatively, it might, in part, represent some other long-term deleterious effect of the graft. Since PET-scan data indicate that the reinnervation obtained is sub-optimal, it will be of interest to obtain a larger and denser reinnervation of the host striatum and to try, thereafter, to reduce the dose of L-dopa.

Aged↗
PubMed1996

Ruptured fusiform aneurysm of the superior third of the basilar artery associated with the absence of the midbasilar artery. Case report.

A case involving the absence of the midthird portion of the basilar artery (BA) associated with a ruptured fusiform aneurysm of the superior third of the basilar artery discovered after a subarachnoid hemorrhage is reported. Surgical clipping was precluded by the anatomical conditions. The aneurysm was treated by occlusion (surgical clipping and balloon occlusion) of both posterior communicating arteries to decrease the hemodynamic stress on the aneurysm wall. The pericerebellar arterial network was allowed to supply the distal BA and its collateral vessels indirectly. This treatment proved to be efficient; angiography and magnetic resonance imaging demonstrated shrinkage of the aneurysm cavity. The absence of the midthird of the BA is usually associated with a persisting trigeminal artery (nonexistent in this case) or disclosed in cases of acute BA occlusion in dramatic clinical conditions. A similar anatomical feature has been described only once before. There may be a segmental maldevelopment of the longitudinal neural arteries during embryogenesis or a defect in fusion of these paired structures during the development of the BA itself.

Adult↗
PubMed1996

Efficacy and safety of iobitridol versus iohexol for contrast-enhanced CT of the head.

PURPOSE: The efficacy and adverse reactions of iobitridol versus iohexol in contrast-enhanced CT (CECT) of the head were investigated. MATERIAL AND METHODS: This double-blind randomized parallel study compared the clinical and biological safety of iobitridol and iohexol (350 mgI/ml), administered intravenously (1 ml/kg) to 276 patients undergoing CECT of the head. Vital signs were assessed just before after injection, and 24 hours after. A biologic examination was performed before and after injection. Both groups were comparable at inclusion. RESULTS AND CONCLUSION: The within-group variation for vital signs after injection and 24 hours after was not clinically relevant and no significant difference was evident between treatment groups. The incidence of adverse events was similar in both groups (11.0% for iobitridol and 7.1 % for iohexol), consisting most often of a sensation of warmth. Biologic parameters remained stable and did not differ significantly between groups. The quality of imaging was rated good or excellent in 70% of cases and a very high diagnostic discrimination was achieved (98%). Iobitridol compared favorably with iohexol for head CECT.

Adolescent↗
PubMed1995

Arteriovenous fistulae complicating central venous catheterization: value of endovascular treatment based on a series of seven cases.

OBJECTIVES: To point out the usefulness and effication of endovascular treatment of arteriovenous fistulae complicating the insertion of central venous catheter. MATERIAL AND METHOD: Retrospective study of 7 cases treated between 1983 and 1993. The central venous catheterization had involved the right internal jugular vein in 5 cases and the right subclavian vein in 2 cases. RESULTS: Isolated endovascular therapy was performed in 5 cases. Surgery was necessary in 1 case to remove an hematoma. In another case, occlusion of a large AVF was performed during intraoperative endovascular temporary occlusion of the AVF. The choice of the occluding agent was primarily dictated by the hemodynamic and anatomical conditions (releasable balloons, coils). Vertebro-vertebral fistulae (3 cases) could be treated with patency of this vessel. No complications were encountered. CONCLUSION: Endovascular approach is a reliable and safe method to perform occlusion of post catheter AVF.

Adult↗
PubMed1995

[Imagery of human immunodeficiency virus (HIV) encephalitis].

The authors present the different aspects of HIV encephalitis in CT and MR in a series of 15 patients with anatomopathological proof. Atrophy was the most commonly found lesion (12 patients) and could rapidly be evolutive. White matter lesions (9 patients) were more of ten nodular than diffuse. They were better demonstrated by MRI and did not enhance after intra-venous injection of DOTA-gadolinium. A frequent association with opportunistic infections (toxoplasmosis: 10 patients, CMV:2 patients), lymphoma (4 patients), or PML (3 patients) was observed which emphasized the low specificity of brain imaging in patients with HIV encephalitis.

AIDS Dementia Complex↗
PubMed1995

[Intra-extracranial meningioma in the cranial vault].

Between 1982 and 1993, 11 cases of intra-extracranial vault meningiomas were treated in Créteil, by the same multidisciplinary team. The average age was 53.5 years and the Karnofsky rating was high (> 80 in 7 cases). Ten of the 11 cases had medial tumours with venous sinus thrombosis occurring in 9 of these. The location of the tumour was frontal in 6 and parietal in 4 patients. Of the medial tumours, 5 (half) were bilateral intracranial lesions. The average duration of symptoms was more than 10 years in four cases, between 1 and 3 years in five, and the diagnosis was made immediately in two patients. MRI coronal sections, after venous contrast injection, allowed diagnosis of the lesion and visualisation of the sinus thrombosis. Embolisation was performed pre-operatively in all cases scheduled to have surgery, resulting in safe excision of the tumour. Surgery was performed in 9 patients with complete tumour removal achieved in 8. Of those who did not undergo surgery, one received radiotherapy and the other died before treatment. The bony defect was covered with cadaveric bone, autogenous bone, coral and methyl-methacrylate in one, two, two and two patients respectively. Complications occurred in 2 cases: extradural secondary infection and CSF rhinorrhea treated with a lumbo-peritoneal shunt. The post-operative Karnofsky rating was greater than 90 in seven cases, 70 in one, and 50 in two cases. After an average follow-up of 4 years, 3 patients had tumor recurrence at 4, 7, and 8 years; the first having a locally malignant character, the second showing radiological recurrence in a case of subtotal removal, and the third a marginal recurrence. Two of the 3 patients underwent further surgery. The malignant case, received radiotherapy but unfortunately a new recurrence occurred 14 months later. As radiotherapy was used in only 3 cases, statistically significant conclusions concerning efficacy cannot be drawn.

Adult↗
PubMed1995

Detection of cerebrovascular disease in patients with sickle cell disease using transcranial Doppler sonography: correlation with MRI, MRA and conventional angiography.

A prospective study of 58 patients with sickle cell disease (SCD) by transcranial Doppler sonography (TCD) included both MRI and MRA in patients over 7 years of age and those with abnormal TCD. Arteriography was performed in cases where a stenosis was suspected on TCD. Middle cerebral artery (MCA) and basilar artery (BA) velocities were significantly higher in the sickle cell hemoglobin SS group than in the hemoglobin SC group. Patients with a MCA mean velocity of over 1.90 m/s had stenoses found by arteriography. Patients with unilaterally undetectable MCA flow had experienced a stroke and MCA thrombosis was confirmed at MRA and arteriography. We concluded that TCD is valuable in detecting arterial stenosis in SCD and will lead to consideration of these patients for intensive therapy, such as bone marrow transplantation (BMT) or transfusion regimes.

Adolescent↗
PubMed1994

[Percutaneous vertebral biopsy].

CT-guided vertebral biopsy is a simple, non dangerous, and usually an effective method for the actiological diagnosis and the treatment of vertebral lesions. The authors detail the biopsy technique, the needles and the route used according to the anatomical distribution and the osteosclerotic or osteolytic aspect of the vertebral lesion. In 60% of ordinary infectious spondylodiscitis the biopsy is positive. Early diagnosis of tuberculous spondylodiscitis is usually possible only to anatomopathological examination on osteodiscal samples. In tumoral disease the association of biopsy and cytological specimens provides the best results, specially in osteolytic vertebral lesions.

Biopsy, Needle↗
PubMed1994

Randomised double blind trial of the safety and efficacy of two gadolinium complexes (Gd-DTPA and Gd-DOTA).

The main difference between macrocyclic Gd-DOTA and linear Gd-DTPA complexes is the greater stability of the former which theoretically might reduce biological interactions in man. To evaluate the clinical relevance of this property, 300 unselected neurological patients were included in a randomised double-blind comparison involving five European centres, focused mainly on the tolerance of these two contrast media. Clinical tolerance was assessed immediately after the procedure and 24 h later. Adverse events were found with a similar frequency in the two groups (17.3% for Gd-DOTA and 19.3% for Gd-DTPA). Minor neurological symptoms were the most frequent (48.6%) headache being the most common (29.2% of adverse events). No difference in efficacy was found.

Adult↗
PubMed1993

Concentric MR patterns in multiple sclerosis. Report of two cases.

We report two cases of multiple sclerosis with concentric patterns of demyelinated foci on MR images. These were compared with the pathological data of Balò's disease. The T2-weighted MR images displayed alternating high and low signal areas which probably corresponded to the concentric type of demyelination. Our two cases were characterized by their acute onset and their regression following corticosteroid therapy. This suggests that Balò's disease may be a transient disease and not always associated with a fatal course.

Adult↗
PubMed1993

[Psychotherapy, psychoanalysis and the therapeutic process].

The authors examine the transformation undergone by psychoanalytically-based theories in the context of therapeutic application and with regard to the concepts of health or mental disease, and in particular in relation to the consideration of each individuality and intersubjectivity derived from psychotherapeutic relations. The paper discusses works by some of the main supporters of this theory: W. Bion, D. Winnicott and M. Khan in the Freudian field; lastly, with regard to analytical psychology, Jung's idea of the practice of psychotherapy and his aims are fully discussed. The "hermeneutic" aspect of all psychotherapy is then emphasised and it is viewed as the intermingling and reciprocal involvement of three factors: theory, technique and interpersonal relations.

Female↗
PubMed1992

CT-guided percutaneous biopsy of the cervical spine: a series of 12 cases.

Twelve patients underwent biopsy of cervical vertebral bodies under CT guidance. An accurate diagnosis was obtained in 11. No complications were observed, except for a transitory recurrent laryngeal nerve palsy. Technical problems of the cervical spine biopsy are discussed and the utility of bone biopsy with a coaxial trephine system is emphasized.

Adult↗
PubMed1992

Trigeminal neuromas: assessment of MRI and CT.

We report four cases of trigeminal neuroma. One of the patients had von Recklinghausen's neurofibromatosis with plexiform neurofibromas of the branches of the trigeminal nerve. MRI provided more information than CT as regards the spread of tumour: extension to the mandibular and maxillary division of the trigeminal nerve was well demonstrated on sagittal and coronal sections. This examination yielded an accurate census of the intraocular plexiform neurofibromas and allowed a correct preoperative diagnosis to be obtained. With Gd-DOTA, better definition of the outline of the tumours and of cystic components was obtained. However, CT was better for demonstration of bone erosions.

Adult↗