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J Clarisse

Publications and source records attributed to J Clarisse.

At least 19 recordsLinked to original sources
PubMed1999

[Interventional MRI. Analysis of data and prospects].

In spite of its many advantages: 3D imaging, improved tissue characterization, and lack of ionizing radiation, interventional MRI remains seldom used. Several factors are involved. The purpose of this paper is to analyze the factors preventing or slowing the development of this technique based on a review of data from the literature, work presented at the second symposium on interventional MRI (Düsseldorf, 1997), and our own experimental data. The following elements will be discussed: difficulties related to image quality and open magnets, control of targeted image acquisitions, MR environment and problems related to asepsis, as well as advances of other techniques. Finally, short-term and mid-term perspectives will be presented. These are related to the goals of the technique: open or short bore closed magnets? MR unit installed in a radiology department? MR unit dedicated to interventional procedures only or mixed diagnostic-interventional unit? interventional MR unit placed in a neurosurgery operating room? interventional MR unit installed in a general surgery operating room?

Analgesia↗
PubMed1998

[Magnetic resonance imaging of the facial nerve in a case of Melkerson-Rosenthal syndrome].

A 35-year-old man treated for a Crohn's disease presented with a second facial palsy in a setting of recurrent labial edema known since childhood. The diagnosis of Melkerson-Rosenthal syndrome was established. MRI showed a small T1 gadolinium-enhanced lesion of the facial nerve suggesting an inflammatory process. Similarities of pathologic lesions found in Melkerson-Rosenthal syndrome, Crohn's disease and sarcoidosis raise the question of the relationships between these disorders.

Adult↗
PubMed1997

[Identification of the central sulcus using the scanner and MRI].

Methods to directly and indirectly identify the central sulcus are presented. In the axial plan, direct method is remarkable but obviously requires good visualization of the sulci in the central region. Sulci are readily visible in 90% of the cases on CT scans and in 50% of the cases on MRI. The method can also be applied when tumoral development erases the cerebral sulci by direct lecture of the controlateral rolandic region and right-left transfer. Within the precision limits of the method, it can be considered that the central sulci are symmetrical. The main signs are: the relative morphologies of the superior frontal sulcus and the precentral sulcus, the hook-shaped aspect of the middle part of the central sulcus, the internal end of the central sulcus projection anteriorly to the pars marginalis, the bifid nature of the internal end of the posterior central sulcus contouring the pars marginalis, and the lesser thickness of the posterior central gyrus compared with the precentral gyrus. The indirect method is less precise and is used when the direct method is unsuccessful. The central sulcus is identified on the sagittal images and, using the lateral view of the skull as a reference image, the topographic information is transferred to the axial images.

Brain↗
PubMed1996

Percutaneous vertebroplasty for osteolytic metastases and myeloma: effects of the percentage of lesion filling and the leakage of methyl methacrylate at clinical follow-up.

PURPOSE: To determine whether the percentage of vertebral lesion filling and the leakage of methyl methacrylate have any clinical significance at follow-up. MATERIALS AND METHODS: Forty percutaneous vertebroplasties were performed for metastases (30 cases) and myeloma (10 cases) in 37 patients. A computed tomographic scan was obtained 1-8 hours after methyl methacrylate injection and was used to assess the percentage of lesion filling by methyl methacrylate and the leakage of methyl methacrylate into the epidural tissues, neural foramina, intervertebral disks, venous plexus, and paravertebral tissue. The results were correlated with those obtained at clinical follow-up. RESULTS: Partial or complete pain relief was sustained in 36 of 37 patients. Pain relief was not proportional to the percentage of lesion filling. Clinical improvement was maintained in most patients. The 15 epidural leaks, eight intradiskal leaks, and two venous leaks of methyl methacrylate had no clinical importance. Two of eight foraminal leaks produced nerve root compression that required decompressive surgery. One of 21 paravertebral leaks produced transitory femoral neuropathy. CONCLUSION: Pain relief can occur despite insufficient lesion filling. In most patients, intradiskal and paravertebral leaks of cement had no clinical importance.

Bone Cements↗
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↗
PubMed1996

Preoperative percutaneous injection of methyl methacrylate and N-butyl cyanoacrylate in vertebral hemangiomas.

PURPOSE: To investigate the usefulness of preoperative percutaneous injections in vertebral hemangiomas. METHODS: Four patients presented with complicated vertebral hemangioma (spinal cord compression in three cases, intermittent spinal claudiction in one case). A three-part treatment was performed: initially, arterial embolization in three cases; 1 day later, percutaneous injections of methyl methacrylate into the vertebral body to strengthen it and of N-butyl cyanoacrylate into the posterior arch to optimize hemostasis during surgery; finally, the day after percutaneous injections, decompressive laminectomy and epidural hemangioma excision (when present). RESULTS: Laminectomy was performed with minimal blood loss. The epidural component present in three cases was excised without any difficulty. The follow-up (average, 20 months) showed no evidence of vertebral collapse. CONCLUSION: Percutaneous injections of methyl methacrylate and N-butyl cyanoacrylate might be useful before surgery for vertebral hemangiomas.

Aged↗
PubMed1994

Marchiafava-Bignami disease: use of contrast media in CT and MRI.

We report two cases of Marchiafava-Bignami disease studied by CT and MRI. Both patients displayed persistent confusion and a disconnection syndrome but had a favourable outcome. In both cases, CT with intravenous contrast medium revealed enhancement of the corpus callosum in the early stage. MRI showed gadolinium uptake in both the genu and splenium of the corpus callosum in one case, 8 days after the onset. Three weeks after admission, cystic lesions appeared in the corpus callosum on MRI T1-weighted sagittal images in both cases. Contrast medium uptake may be useful in the diagnosis of Marchiafava-Bignami disease.

Adult↗
PubMed1994

Antenatal differentiation of the human intervertebral disc.

To study the antenatal differentiation of the human intervertebral disc, the columns of forty eight embryos and fetuses were examined histologically. The primitive disc is composed of two structures: the notochord which shows a progressive expansion into the disc, and the fibro-cartilaginous perinotochordal disc. No histological sign of interaction between notochordal and perinotochordal cells, which may explain the notochordal expansion into the discs, was seen. On the other hand, the notochordal intervention in the cartilaginous differentiation of the inner zone is probable.

Gestational Age↗
PubMed1994

Pituitary microadenomas: experience with Gd-DOTA-enhanced MR imaging at 0.5 Telsa.

PURPOSE: We report our experience with magnetic resonance imaging at 0.5 Tesla in the radiological diagnosis of pituitary adenomas. METHODS: Over 2 years we performed a prospective study in 38 patients with pituitary microadenomas to assess the potential additional benefit of gadolinium in the detection of small intrasellar lesions. The protocol included three coronal T1-weighted sequences: precontrast, early postcontrast (obtained less than 2 min after injection) and late postcontrast (obtained 5 min after injection). For each sequence lesions were classified according to their visibility into three categories: definite lesion, probable lesion or absent lesion. RESULTS: Lesions were classified as well-defined in 55% of patients on the precontrast study, 89.5% on the early postcontrast study and 60.5% on the late postcontrast study. Of nine microadenomas not detected on the precontrast scans, all were clearly seen on the early post contrast scans; only four were well-defined on the late postcontrast study. Only one lesion was not seen on the early postcontrast study but was well-defined on precontrast study as a spontaneous high-intensity focal area: it was a hemorrhagic microadenoma. CONCLUSION: Our results suggest that the early postcontrast study is the most useful sequence for the detection of microadenomas. Precontrast image is necessary to detect hemorrhagic lesions; the late postcontrast sequence has a low additional diagnostic yield and seems unnecessary unless the other sequences are inconclusive.

Adenoma↗
PubMed1994

Causes of dislocation of total hip arthroplasty. CT study of component alignment.

We reviewed radiographs and CT scans of 38 total hip arthroplasties which had dislocated (36 posteriorly; 2 anteriorly) and compared the alignment of the prosthetic components with those of 14 uncomplicated arthroplasties. No difference was found between the alignment of the prosthetic components in the two groups. In the seven patients who had reoperations, the cause of dislocation diagnosed by CT was confirmed in only two cases (one retroversion of the cup and one protruding osteophyte). Muscular imbalance rather than malposition of the components was the major factor determining dislocation. CT allows accurate measurement of cup and neck anteversion but contributes little to preoperative planning.

Adolescent↗
PubMed1993

[Searching for prolactin microadenoma: scanner or MRI?].

Thirty three hyperprolactinemic women, aged 16-46 years, have been investigated by pituitary CT and MRI scans, searching for a microadenoma. The MRI scan with Gadolinium injection (MRI G+) appeared more efficient than the CT scan to detect a picture highly suggestive of a microprolactinoma (30/33 positive scans vs 21/33, respectively, p = 0.06). However, when the CT scan was performed optimaly (i.e. thin cuts, sequential imaging after iode injection, no artefact), its diagnostic potenty was close to the one of MRI G+, missing only 17.6% of lesions. All these were less than 5 mm in diameter. The indirect signs of microadenoma (focal convexity of the superior surface of pituitary, tilting of pituitary stalk, focal sella floor erosion or destruction) had a minimal value. Their sensitivity was 66.6% and 63.3 for convexity, and 63.3 and 46.6% for tilting of pituitary stalk, by MRI and CT scans, respectively. Therefore, they did not afford any help in our experience. Considering the cost and the limited accessibility of MRI, at least in our country, we advise to use CT scan as the primary morphologic means to detect a microadenoma.

Adolescent↗
PubMed1992

Parkinson's disease and basal ganglia calcifications: prevalence and clinico-radiological correlations.

We reviewed computerized tomograms (CT) for basal ganglia and dentate nucleus calcifications in 79 patients with Parkinson's disease (PD), 54 patients with Alzheimer's disease (AD) and 109 controls aged 50 or more. When it was determined, no patient had disturbances in calcium metabolism. We found: (1) 30 subjects out of 242 (12.3%) with calcification located within the lenticular nucleus in 28. (2) Calcifications were unilateral in 11 and asymmetric in 11. (3) The prevalence of calcifications was 21.5% in PD, 9.2% in AD and 7.3% in controls and were significantly more severe in PD than in C and AD (P less than 0.02). (4) PD patients with calcifications were clinically indistinguishable from those without calcification. (5) Calcifications within the basal ganglia were not associated with a levodopa-resistance. We suggest the basal ganglia calcifications are more frequent in PD, but we cannot explain why, since post-synaptic lesions have never been showed in PD.

Aged↗
PubMed1991

The stereotactic approach to brain stem lesions: a follow-up of 29 cases.

Stereotactic biopsy is the safest and most reliable method for the histological diagnosis of intraaxial brain stem lesions. The definitive pathological diagnosis permits the selection of adequate therapy. No operative and/or adjuvant therapy must be proposed without a previous histological diagnosis. This approach avoids the complication of inappropriate therapy and provides valuable prognostic information.

Adolescent↗
PubMed1991

Could Wallerian degeneration contribute to "leuko-araiosis" in subjects free of any vascular disorder?

To determine the possible role of Wallerian degeneration secondary to the grey matter neuronal loss in the pathogenesis of "leuko-araiosis", computerised tomography (CT) of the brain was studied in 98 normotensive and non diabetic subjects free of cardiac diseases: 32 with Alzheimer's disease, 36 with Parkinson's disease, eight with progressive supranuclear palsy, and 22 controls. In Alzheimer's disease, leuko-araiosis scores were greater than in control subjects. Leuko-araiosis was more prominent in anterior periventricular areas in Parkinson's disease and progressive supranuclear palsy, and in posterior periventricular areas in Alzheimer's disease. In two patients with Alzheimer's disease and leuko-araiosis, necropsy revealed diffuse white matter pallor, mild fibrillary astrocytosis, and in one patient limited hyaline thickening of small white matter vessels, without any infarction or hypertensive change. Changes were more severe in white matter close to cortical areas with a great density of neurofibrillary tangles. Leuko-araiosis was more severe or more widespread in Alzheimer's disease than in Parkinson's disease, progressive supranuclear palsy and normal ageing. Differences in the location of leuko-araiosis between the four groups might be due to differences in the location of the grey matter disorder and Wallerian degeneration rather than amyloid in Alzheimer's disease, Parkinson's disease, progressive supranuclear palsy and normal ageing. Wallerian degeneration might be another cause of leuko-araiosis in neuro-degenerative disorders beside previously reported extra-cerebral predisposing factors and amyloid angiopathy.

Aged↗