Biomedical subjects

R Anxionnat

Publications and source records attributed to R Anxionnat.

At least 37 records · Page 2Linked to original sources

PubMed2000

[Thrombosis of deep cerebral veins in form adults: clinical features and diagnostic approach].

Thrombosis of deep cerebral veins is a rare condition, and is associated with a poor prognosis. We report four new cases observed between 1994 and 1997. All four cases were women, aged less than 45 years. Initial symptoms associated alteration of consciousness, change in mental status, progressive headache and vomiting. We observed also uni or bilateral signs of long tract injury. In three cases, diagnosis initially suspected by CT scan was confirmed with encephalic MRI. For the last patient, conventional angiography was needed. Thrombosis affected straight sinus, vein of Galien and internal cerebral veins in all patients. Basilar veins were also affected in one patient, without dural sinuses extension. Lateral sinus was involved in two others cases, and superior sagittal in the last patient. Etiology remains undetermined in one patient, associated with post-partum, use of oral contraceptive pill, and familial protein S deficiency, one case each. Outcome was favorable in all four cases with anticoagulation therapy. Precocity of diagnosis is determinant and MRI is usefull in this issue. These observations show that evolution of deep veins thrombosis can be favorable, without needing fibrinolytic therapy.

Adult↗

PubMed1999

[Paraneoplastic opsoclonus-myoclonus syndrome revealing T-cell lymphoma].

BACKGROUND: Nonrhythmic involuntary ocular oscillations and axial and segmentary myoclonia are associated in the opsoclonus-myoclonus syndrome. In adults, a paraneoplastic origin is generally found. We report the first of opsoclonus-myoclonus associated with non-Hodgkin's lymphoma. CASE REPORT: A 66-year-old woman rapidly developed a typical opsoclonus-myoclonus syndrome within a few hours, presenting vertigo, cerebellous ataxia, multidirectional involuntary ocular movements and non-rhythmic axial and segmentary myoclonia. Brain computed tomography and magnetic resonance imaging demonstrated discrete diffuse anomalies of the white substance predominating in the pons. The cerebrospinal fluid showed discrete lymphocytosis. Antineuron antibodies were negative. No cause could be identified until the development 11 months later of pleomorphic T-cell mediastino-cervical lymphoma. The patient responded moderately to a CHOP regimen which had no effect on the opsoclonus-myoclonus syndrome. Death occurred after a 16-month course due to pulmonary complications. DISCUSSION: Neuroblastoma and infectious causes predominate in opsoclonus-myoclonus syndromes observed in children; in adults, the predominant cause is cancer. Antineuron, anti-Ri and anti-Hu antibodies can be evidenced in some cases, arguing in favor of a paraneoplastic mechanism. Recent reports have evidenced MRI anomalies in the pons and the cerebellum, anatomically well correlated with the opsoclonus-myoclonus syndrome. Besides small-cell bronchogenic anaplastic cancer, the possibility of cancer of the breast and uterus, and both non-Hodgkin and Hodgkin lymphoma should be explored, knowing the cancer develops several month after the opsoclonus-myoclonus syndrome.

Aged↗

PubMed1999

[Endovascular treatment of vasospasm].

Cerebral vasospasm remains a leading cause of heightened morbidity and mortality rates following aneurysmal subarachnoid hemorrhage despite the apparent benefit of recent medical therapeutics. Successful resolution of medically refractory angiographically demonstrated vasospasm with concomitant reversal of delayed neurological deficit has been observed after balloon angioplasty. Subsequent reports confirmed these encouraging results but also emphasized the limitations of the technique and the risks of complications. Intraarterial papaverine infusion has been performed for the treatment of diffuse cerebral vasospasm with controversial results and has also been combined with angioplasty either to facilitate balloon navigation or to treat arteries inaccessible to balloon catheterization. All these different endovascular approaches explain the confusion existing about the indications, timing and efficacy of the endovascular treatments. This article reviews several clinical and experimental studies dealing with these questions.

Angioplasty, Balloon↗

PubMed1999

[Diffusion imaging in asymptomatic focal vasospasm. Apropos of a case].

We report a case of an asymptomatic vasospasm with a focal, reversible apparent diffusion coefficient (ADC) decrease after a middle cerebral artery aneurysm rupture. This isolated decrease of ADC has not yet been reported in this pathological situation. It could be interesting to predict the risk of ischemic delayed complications of vasospasm.

Adult↗

PubMed1998

3D angiography. Clinical interest. First applications in interventional neuroradiology.

3D angiography is a true technical revolution that allows improvement in the quality and safety of diagnostic and endovascular treatment procedures. 3D angiography images are obtained by reconstruction of a rotational angiography acquisition done on a C-arm (GE Medical Systems) spinning at 40 degrees per second. The carotid or vertebral selective injection of a total of 15 ml of non-ionic contrast media at 3 ml/sec over 5 seconds allows the selection of the "arterial phase". Four hundred sixty 3D angiographic studies were performed from December 1996 to September 1998 on 260 patients and have been analyzed in MIP (Maximum Intensity Projection) and SSD (Shaded Surface Display) views. The exploration of intracranial aneurysms is simplified and only requires, for each vascular axis, a biplane PA and Lateral run followed by a single rotational angiography run. The 3D angiography image is available on the workstation's screen (Advantage Workstation 3.1, GE Medical Systems) in less than 10 minutes after the acquisition of the rotational run. It therefore allows one to analyze, during the intervention, the aneurysm's angioarchitecture, in particular the neck, and select the best therapeutic technique. When endovascular treatment is the best indication, 3D angiography allows one to define the optimal angle of view and accurately select the microcoils dimensions. 3D angiography replaces the multiple oblique views that used to be required to analyze the complex aneurysms and therefore allows a reduction of the total contrast medium quantity, the patient X-ray dose and the length of the intervention time which is a safety factor. Also, in particular for complex cases, it brings additional elements complementing the results of standard 2D DSA and rotational angiograms. In the cervical vascular pathology, 3D angiography allows for a better assessment of the stenosis level and of dissection lesions. Our current research activities focus on the matching without stereotactic frame between 3D X-ray angiography and volumetric MR acquisition, which should allow us to improve the treatment of intracerebral arterio-venous malformations (AVMs).

Aortic Dissection↗

PubMed1998

[MRI aspects of spinal cord abscesses. Report of 5 cases and review of the literature].

The spinal canal is an uncommon site for abscess formation resulting from bloodstream disseminated infection. Prognosis is often unfavorable. Rapid treatment is essential for satisfactory neurological recovery. Abscesses within the spinal canal are thus diagnostic and therapeutic emergencies. The neuro-infectious and inflammatory manifestations and laboratory findings vary considerably and are insufficient for diagnosis. MRI plays a decisive role. The most commonly reported signs are the presence of an intramedullary collection giving a low-intensity signal on T1-weighted images and a high-intensity signal on T2-weighted images with peripheral contrast uptake and generally extended adjacent medullary edema. We report here five cases of spinal canal abscesses diagnoses with MRI at different stages of development (pre-suppurative myelitis in two cases, constituted abscess in three cases). For each case we reviewed the clinical course and describe the details of the imaging findings. In our series, the collected abscesses presented as round lesions within the canal with contrast uptake. It is noteworthy that the periependymal gray matter adjacent to the lesion also took up the contrast agent in all patients with a collected abscess. This sign has not been described previously and appears to be a going argument orienting the diagnosis towards an infectious rather than tumoral formation.

Abscess↗

PubMed1997

Intravenous angiography in brain death: report of 140 patients.

We present our experience and discuss the value of cerebral intravenous digital subtraction angiography (IV DSA) in the diagnosis of brain death. A total of 140 patients presenting with clinical signs of brain death were studied by IV DSA. According to the angiographic appearance of the vertebrobasilar system, the patients were divided into four groups. Cessation of blood flow within the internal carotid arteries and their branches was consistently found. Attention is focused on 9 patients with persistent blood flow within the posterior fossa. In sedated patients in whom EEG and evoked brain-stem responses are non-diagnostic, or in order to shorten the observation time, transcranial Doppler should be performed to determine the appropriate moment for IV DSA, which is a reliable method of confirming brain death.

Adolescent↗

PubMed1997

Stroke related to a dermoid cyst: case report.

OBJECTIVE AND IMPORTANCE: We report the case of a woman presenting with sudden neurological deficit, revealing a parasellar dermoid cyst. To our knowledge, this clinicopathological finding is the first reported in the literature. CLINICAL PRESENTATION: A neurological examination of the patient revealed a left hemiparesis, including central facial palsy, which hampered her speech. The well-documented neuroradiological work-up (including computed tomography, magnetic resonance imaging, and magnetic resonance angiography) demonstrated right frontorolandic ischemia caused by a right supra- and parasellar dermoid cyst leading to middle and anterior cerebral arterial stenoses. INTERVENTION: Surgical intervention, using a right subfrontopterional approach, was successful. Complete dermoid cyst removal was achieved. The mechanism of the arterial stenoses is extensively discussed and is thought to result from an inflammatory reaction of the basal vessels. CONCLUSION: The patient recovered fully. Nevertheless, postoperative magnetic resonance imaging confirmed cerebral infarction.

Adult↗

PubMed1997

X-ray angiography in stereotactic conditions: techniques and interest for interventional neuroradiology.

This paper reports work in progress on X-ray angiography acquired under stereotactic conditions. The objective is to be able to match multimodality images (typically MRI and X-ray) without a stereotactic frame but with stereotactic precision. We have identified potential problems and have studied them in detail. We conclude that, although the overall application is feasible, much work remains to be done on the estimation of the X-ray system conic projection and on automatic matching based on vascular structures.

Angiography, Digital Subtraction↗

PubMed1996

Endovascular occlusion of intracranial aneurysms of the posterior circulation: comparison of balloons, free coils and detachable coils in 38 patients.

We treated 38 patients with 39 aneurysms of the posterior circulation by an endovascular technique using balloons, free coils or Guglielmi detachable coils (GDC) from 1986 to May 1993. The patients ranged in age from 10 to 71 years. Subarachnoid haemorrhage was the most frequent presentation (29 patients), followed by mass effect (5 patients) and epilepsy (2 patients). Treatment consisted of embolisation of the aneurysm with preservation of the parent vessel (in 29) or occlusion of the parent vessel (in 5). Multiple procedures were performed in 12 patients (32%, maximum 3 embolisations, total 17 treatments), because of incomplete initial aneurysm occlusion (in 8 cases) or re-opening of the aneurysm (in 9). Treatment could not be achieved in 5 patients. Good to excellent aneurysm occlusion was obtained in 28 patients (72%). Little or no neurological impairment occurred in 31 patients (82%). Complications related to treatment (11 patients, 29%) included 4 cases of transient cerebral ischaemia, 7 of stroke resulting in minimal neurological impairment (in 5), severe impairment (in 1) and one death. There were 6 patients who died, of rebleeding from the same aneurysm (2), basilar stroke (1) and unrelated causes (3). Comparison of the different occlusion techniques showed that the best angiographic results were obtained with balloons (good to excellent aneurysm occlusion was obtained in 17 of 22 patients treated) and the GDC (12 of 13 patients), and that less good results were given by free coils (4 of 9 patients). Complications related to treatment were fewest in patients treated with GDC (1 of 16 treatments, including multiple procedures) or free coils (2 of 12 treatments) and were more frequent with balloons (6 of 27 treatments). All five treatment failures occurred with balloon embolisation, whereas treatment was possible in all cases treated with free coils or GDC.

Adolescent↗

PubMed1996

The veins of the medulla oblongata: MRI cross-sectional anatomy.

Magnetic resonance imaging (MRI) has progressively become the major or even the only imaging procedure for displaying the vascular relationships of the brainstem in the context of infra-tentorial lesions. In order to assess the MR sectional anatomy of the bulbar vv. 40 normal patients were examined in the MR axial, frontal and sagittal planes after gadolinium i.v. injection. The bulbar venous networks were inconstantly visualised: anterior vv. (16%). posterior (3%), lateral (8%). The vein of the lateral recess of the fourth ventricle was constant in the three planes; the inferior petrosal sinus could be seen in 82% of cases. Their relation with the posterior fossa structures are emphasised and discussed.

Contrast Media↗

PubMed1996

[Endovascular treatment of intracranial aneurysms].

Major improvements have been achieved in endovascular treatment of intracranial aneurysms during the last twenty years. Initial techniques of selective balloon occlusion were progressively replaced by the packing of the aneurysmal pouch with very small and soft metallic devices, named coils, with controlled detachment. In some rare cases, balloon occlusion is still used in order to occlude the parent vessel or to reverse the flow, especially in the vertebro-basilar system. Essential aims for the anaesthesiologist include: complete immobility of the patient throughout the endovascular procedure, systemic anticoagulation in order to avoid any thromboembolic complication during and after treatment, prevention and/or treatment of vasospasm, precise evaluation of fluid balance during the procedure. Our experience is based on 145 aneurysms in 135 patients, treated by endovascular route; 91 (63%) of them were revealed by a subarachnoid haemorrhage (SAH). Their main locations were: the carotid siphon (33.1%), the anterior communicating artery (19.3%), the basilar artery (17.2%) and the middle cerebral artery (17.2%). Thirty-seven of these aneurysms (25.5%) were very small in size with a diameter less than 4 mm. Total or sub-total (more than 90%) occlusion was achieved in 141 aneurysms (90.3%). Thromboembolic complications occurred in eight patients (5.9%), neurological sequelae in one. Other treatment-related complications included the migration of a coil outside the aneurysm in six cases (4.4%) without neurological deficit in one and five ruptures of the aneurysm (3.7%) during the procedure with one lethal issue due to the spontaneous bleeding of a controlateral arterio-venous malformation. Thirteen patients died (9.6%). The cause of the death was related on the initial SAH in 11 of them. The two others were both due to rupture: of a second untreated aneurysm in one case and of an associated arteriovenous malformation in the second one. At present the main indications of endovascular treatment are poor or non indications for neurosurgery. Due to the quality of results, endovascular therapy will be more and more used in case of ruptured or non ruptured aneurysms.

Cerebral Angiography↗

PubMed1996

[Endovascular treatment of vasospasm].

Various therapeutic strategies have been recently proposed to prevent the vasospasm after subarachnoid haemorrhage, and to avoid its clinical consequences. Despite these progresses, mortality and morbidity of delayed ischaemic consequences of vasospasm remain important. Two endovascular treatments have been proposed. The successful use of transluminal angioplasty for vasospasm was first reported by Zubkov in 1984. Transluminal angioplasty is very effective with clinical improvement when the treatment is undertaken without delay after the onset of symptoms. Limitations of this technique are the inaccessibility of distal arteries and the risks (vascular rupture or occlusion). More recently, to overcome these limitations, a selective intraarterial infusion of papaverine has been proposed. These infusions are less risky and can be employed in distal vasospasm. However, clinical results seem to be less favourable and often transient. These two techniques are still used with slightly different indications. According to our experience, it seems reasonable to reserve transluminal angioplasty for symptomatic vasospasm, associated with papaverine or not, and to use papaverine alone in all other cases.

Angioplasty, Balloon↗

PubMed1995

[Venous angiography: importance in the diagnosis of brain death. 125 cases].

According to many ethical and humanitarian arguments, the diagnosis of "brain death" is more and more an emergency. The forensic criteria include abolition of consciousness, abolition of brain stem reflexes, abolition of spontaneous breathing joined to electrocerebral silence. However using EEG criteria of electrical silence may be unreliable because of technical artefacts or depressed electrical activity due to drug intoxication and hypothermia. Venous angiography was used in 125 cases: our experience proves reliability and efficiency of angiographic criteria for diagnosis of brain death. For organ transplant, it is better to be as fast as possible: transplanted organ will be better and it reduces the cost of a long useless intensive care. When it is necessary, we suggest to allow the choice between EEG and angiography.

Brain Death↗

PubMed1995

[The anatomy and the MRI anatomy of the interhemispheric cerebral commissures].

Correlation of myelin-stained or cryotomic sections of human brain with inversion-recovery MR images can display the cerebral commissures as white-matter tracts (in hypersignal on MRI), crossing the mid-line. MRI shows routinely in three orthogonal planes a) the corpus callosum stretched above the supra-tentorial ventricles, it's four portions (rostrum, genu, body and splenium) and connections with the Deep Grey Nuclei b) the fornix, intralimbic commissure joining anteriorly the mammillary bodies (through it's columns) to the alveus posteriorly and inferiorly (via it's two crura), arcing around the thalamus and lying over the hippocampus and the dentate gyrus as shown on the frontal sections c) the anterior commissure, white-matter tract connecting the two temporal lobes. In axial view, the anterior commissure has the shape of bicycle handlebars, coursing posteriorly, inferiorly and laterally behind the head of the caudate nucleus and passes into the lateral nucleus of the globus pallidus into the inferior and middle temporal gyri. Because the anterior commissure is easily recognisable in all planes, it's appears to be a important landmark for identification of the lateral and medial nuclei of the globus pallidus on axial and sagittal planes d) at least, the posterior commissure, anterior margin of the pineal region, closely related to the superior colliculi, acquire a major importance in the AC-PC line delineation becoming a reference landmark for stereotatical procedures.

Brain↗

PubMed1994

Present status of computerized tomography and angiography in the diagnosis of cerebral thrombophlebitis cavernous sinus thrombosis excluded.

In order to evaluate the contribution of computerized tomography (CT) to the diagnosis of cerebral thrombophlebitis, a series of 28 cases was reviewed and compared with data from the literature. In an examination carried out 4 to 5 days of its constitution the thrombus may be directly visualized as a spontaneous hyperdensity. This early but very transient sign, called "cord sign", can easily be overlooked, which explains why it was found in only 5 of our 28 cases and in 2% of the largest series of the literature. The thrombus thereafter becomes hypodense and can be intensified by peripheral contrast enhancement which produces the classical "delta sign". This sign is more frequent: 13/28 in our series and 16 to 30% in published cases. It is usually found in the superior sagittal sinus and must be distinguished from anatomical variations which are common at that level. These two direct signs acquire a greater value when associated with such indirect signs as diffuse or localized cerebral oedema (12 to 52%) and venous ischaemia (22 to 59%). Venous ischaemia is characterized by its strong bleeding potential (more than 50% of the cases) and by its usually favourable course; these two elements and its site differentiate it from arterial ischaemia. Finally, venous stasis is responsible, in 5 to 19% of the cases, for intense enhancement of the tentorium cerebelli; this sign is not specific but easy to evidence and of great value when associated with a direct sign. Dilatation of cortical veins, found in 4 of our 28 cases, also seems to be an interesting sign which, to our knowledge, has not yet been mentioned in the literature. Since in 3.6 to 26% of the cerebral thrombophlebitis the CT scan is normal, a negative CT examination does not rule out this disease, and in many cases the exploration must be rapidly completed by angiography or MRI. Because it is non-invasive and very sensitive to flows, MRI has become the key examination to assert the diagnosis. Angiography is now restricted to those cases where cases where MRI cannot be performed promptly or to certain, purely cortical thrombophlebitis which might pass unnoticed at MRI. When carried out and interpreted cautiously, angiography always shows the venous thrombosis, its exact size and its suppletive network. The results of this study show that MRI alone can diagnose cerebral thrombophlebitis in most patients, that CT well done and interpreted often provides useful but seldom sufficient indices, and that angiography should be reserved for difficult cases.

Cavernous Sinus↗

PubMed1994

MRI in cerebral venous thrombosis.

Fifty-three patients with cerebral venous thrombosis (CVT) were explored by MRI. Three types of signal abnormalities were observed in thrombosed sinuses: 1) isosignal on T1-weighted sequence and low-intensity signal on T2-weighted sequence (early stage); 2) high-intensity signal on T1-and T2-weighted sequences (intermediate stage); 3) isosignal on T1-weighted sequence and high-intensity signal on T2-weighted sequence (late stage). Signal abnormalities in dural sinuses enabling CVT to be diagnosed were absent in 2 out of 53 cases. Twenty-six out of 53 patients had venous infarction. These lesions were haemorrhagic in 20 cases. MRI made it possible to follow the course of CVT in 15 cases, showing partial or complete recanalization of the occluded sinuses in 14 cases. Our study confirmed that MRI is an excellent non-invasive method to explore CVT. It diagnoses the venous thrombosis, studies parenchymal lesions and follows the course of CVT under treatment. However, MRI is less sensitive than arteriography, particularly in cases of CVT involving only the cortical veins.

Adolescent↗

PubMed1994

Dissection of intracranial vertebral arteries revealed by subarachnoidal haemorrhage. Report of seven cases.

Between April 1986 and April 1991, seven cases of meningeal haemorrhage consecutive to dissection of the 4th segment of a vertebral artery were observed at the Neuroradiology Department of the Nancy University Hospital. Four of the 7 patients were men, and 3 were women; mean age varied from 45 to 61 years. The clinical presentation was not suggestive, except in one case where the haemorrhagic episode was associated with Wallenberg's syndrome, pointing to the aetiological diagnosis. The outcome was variable. Two patients died of early complications of the haemorrhage which occurred before treatment could be given. In 2 others patients treated with antiplatelet agents the outcome was favourable; however, at angiography the lesions regressed in one of these two patients, but they progressed in the other with formation of a false aneurysm. The remaining 3 patients were treated by endovascular occlusion of the lesion-bearing vessel: one died of complications of a haemorrhage-induced vasospasm; the other two are symptomless after a 2 to 6 months follow-up.

Aortic Dissection↗