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P Lasjaunias

Publications and source records attributed to P Lasjaunias.

At least 19 recordsLinked to original sources
PubMed2006

Multiple mirror-like intracranial aneurysms. Report of a case and review of the literature.

While multiple intracranial arterial aneurysms occur in 26.4% of patients with aneurysms, in our practice bilateral mirror-like aneurysms are encountered in 9.4% of patients. Multiple mirror aneurysms in the same patient are exceedingly rare. We report a case of mirror-like middle cerebral artery aneurysms associated with mirror-like posterior inferior cerebellar arteries aneurysms and discuss their significance. Although an exceptional finding, multiple mirror-like aneurysms may shed light on the vulnerability of different arterial segments to specific diseases.

Cerebellum↗
PubMed2006

[Diffusion tensor imaging and tractography of central pontine myelinolysis].

OBJECTIVES: To illustrate the value of diffusion tensor imaging and tractography in the diagnosis and follow-up of central pontine myelinolysis. CASE REPORT: We report a case of central pontine myelinolysis in a 29 year old woman, also anorexic, studied using MR Diffusion Tensor Imaging (DTI) and Fibre Tracking (FT) focused on the pons, and compared with the studies of 5 normal volunteers. Tractography showed a swollen aspect of the right corticospinal fiber tract correlating with mild left lower extremity deficit at clinical evaluation. The pontine fibers were posteriorly displaced but intact. The sensory tracts were also intact. Apparent Diffusion Coefficient values were increased and Fractional Anisotropy was decreased in the lesions. Follow up imaging showed persistent abnormal ADC and FA values in the pons although the left cortico-spinal tract returned to normal, consistent with the clinical outcome. CONCLUSION: Diffusion Tensor Imaging MR and Fiber tractography are a new method to analyse white matter tracts. It can be used to prospectively evaluate the location of white matter tract lesions at the acute phase of central pontine myelinolysis and follow up.

Adult↗
PubMed2006

MR diffusion tensor imaging and fiber tracking in 5 spinal cord astrocytomas.

Spinal cord astrocytomas are rare neoplasms that can result in alteration of the spinal cord structural integrity, which can be assessed by using diffusion tensor imaging methods. Our objective was to visualize the deformation of the posterior spinal cord lemniscal and corticospinal tracts in 5 patients with low-grade astrocytomas compared with 10 healthy volunteers by using 3D fiber-tracking reconstructions.

Adult↗
PubMed2006

Perfusion-weighted MR imaging studies in brain hypervascular diseases: comparison of arterial input function extractions for perfusion measurement.

BACKGROUND AND PURPOSE: Brain hypervascular diseases are complex and induce hemodynamic disturbances on brain parenchyma, which are difficult to accurately evaluate by using perfusion-weighted (PWI) MR imaging. Our purpose was to test and to assess the best AIF estimation method among 4 patients with brain hypervascular disease and healthy volunteers. METHODS: Thirty-three patients and 10 healthy volunteers underwent brain perfusion studies by using a 1.5T MR imaging scanner with gadolinium-chelate bolus injection. PWI was performed with the indicator dilution method. AIF estimation methods were performed with local, regional, regional scaled, and global estimated arterial input function (AIF), and PWI measurements (cerebral blood volume [CBV] and cerebral blood flow [CBF]) were performed with regions of interest drawn on the thalami and centrum semiovale in all subjects, remote from the brain hypervascular disease nidus. Abnormal PWI results were assessed by using Z Score, and evaluation of the best AIF estimation method was performed by using a no gold standard evaluation method. RESULTS: From 88% to 97% of patients had overall abnormal perfusion areas of hypo- (decreased CBV and CBF) and/or hyperperfusion (increased CBV and CBF) and/or venous congestion (increased CBV, normal or decreased CBF), depending on the AIF estimation method used for PWI computations. No gold standard evaluation of the 4 AIF estimates found the regional and the regional scaled methods to be the most accurate. CONCLUSION: Brain hypervascular disease induces remote brain perfusion abnormalities that can be better detected by using PWI with regional or regional scaled AIF estimation methods.

Adolescent↗
PubMed2006

MR diffusion tensor imaging and fiber tracking in inflammatory diseases of the spinal cord.

PURPOSE: Our aim was to study the fractional anisotropy (FA) variations and the fiber tracking (FT) patterns observed in patients with myelitis. MATERIAL AND METHODS: Fifteen patients with symptomatic myelitis and 11 healthy subjects were prospectively selected. We performed T2-weighted and diffusion tensor imaging on a 1.5T MR scanner. FA and apparent diffusion coefficient maps were computed in both healthy subjects and patients. In each patient, we performed FT to study pathologic aspects on this imaging method. FA data were analyzed by using z-scores. RESULTS: For the healthy subjects, averaged FA values ranged from 0.745 to 0.751. All abnormal areas seen on T2-weighted imaging had a significantly decreased FA value. In 9 patients (60%), FA maps showed decreased FA areas, whereas T2-weighted imaging findings were normal. These areas matched the neurologic deficit in 33%. Eighty percent of patients had multiple decreased FA areas. Five patients (33%) had increased FA values in normal T2-weighted areas. CONCLUSION: We observed specific FA and FT pattern variations in patients with myelitis.

Adult↗
PubMed2005

Brain MR diffusion tensor imaging and fibre tracking to differentiate between two diffuse axonal injuries.

We report here two cases of diffuse axonal injury (DAI) studied by MR diffusion tensor imaging (DTI) and fibre tracking (FT) focused on the corpus callosum. In one case, DTI and FT pattern matched the diagnosis of broken white matter tracts. In the other case there was a discrepancy between DTI and FT data that showed unaltered white matter tracts with the presence of intra-cellular oedema. These data suggested that DTI and FT are able to differentiate between traumatic cytotoxic oedema and broken fibres in the case of DAI.

Adult↗
PubMed2005

Pial arteriovenous fistulas: dilemmas in prenatal diagnosis, counseling and postnatal treatment. Report of three cases.

We report three cases of the antenatal appearance of a pial arteriovenous fistula (AVF). In Case 1, the diagnosis of pial AVF was made by ultrasound examination at 32 + 3 weeks of gestation and confirmed by magnetic resonance imaging (MRI) at 34 + 3 weeks of gestation. After birth, the neonate had cardiac insufficiency and an embolization was performed 8 days postpartum which was followed by extended cerebral ischemia and death. In Cases 2 and 3 pial fistulae were diagnosed at birth. In Case 2, the patient was referred following the diagnosis of an aneurysmal malformation of the vein of Galen at 38 weeks of gestation. Owing to immediate delivery following her transfer, no ultrasound examination was performed and the diagnosis of pial AVF was established on the first postnatal day. An embolization was performed and the child is doing well. Case 3 presented with cardiomegaly at 30 weeks of gestation and cerebral ischemic lesions after birth. These cases highlight the difficulties encountered in the prenatal diagnosis of pial AVFs. The diagnosis should be considered in cases of unexplained cardiomegaly and it is also important to make sure that AVFs draining into the vein of Galen are not misdiagnosed as aneurysmal malformations of this vein. The complications of pial AVFs are cardiac failure and cerebral ischemia. Embolization is the treatment of choice; however it is a risky procedure in neonates.

Adult↗
PubMed2005

Supratentorial cerebral arteriovenous fistulas (AVFs) in children: review of 41 cases with 63 non choroidal single-hole AVFs.

PURPOSE: In this article we explore the various aspects of the supratentorial Single-Hole AVFs (ST AVFs) in children, focusing on their clinical features, angio-architecture, treatment indications and the role and results of endovascular management. MATERIALS AND METHODS: Among 1565 cases of brain AVMs seen at our neurovascular center, 620 cases were seen in the pediatric age group (<or= to 15 year-old) and 303/620 were non-Galenic brain AVMs. Among 52 brain AVFs found in children, we reviewed 41 pediatric patients with supratentorial single-hole cerebral AVFs (M/F=28/13) with a total of 63 AVFs. Mean age at presentation was 24 months. Four cases had their lesion diagnosed in utero without particular prognostic significance. 17 cases were multifocal with a total of 39 AVFs. The most common clinical presentation leading to diagnosis was cardiac sufficiency in (31.7%), epilepsy (24.4%), macrocrania (14.6%). Venous ectasia (87.8%) and pial venous stenosis (41.5%) were the most frequent angiographic features. There were 11 cases of Hemorrhagic Heriditary Telangiectasia (HHT1) (including two suspicious cases) among the 41 patients (26.8%) and among those 4 cases had single AVFs and 7 cases had multiple AVFs. RESULTS: Thirty-five children were treated in our institution: 34/35 by embolization alone, 1/35 by a combination of embolization and radiosurgery. 32/35 patients were treated with glue alone, 3/35 with coils (2/3 with glue also). A total of 57 separate lesions were treated. On clinical follow up (from 1985-2002, mean 4.2 years), 88.6% of patients proved to be either asymptomatic, improved from previous clinical symptoms or stabilized. 40% of patients had their lesion(s) already completely excluded. Post operative mortality was 5.6% (2/35), permanent neurological morbidity 3% (1/33). Twenty-six of these 33 patients (78.6%) were neurologically normal. 5/33 patients continue to have neurological symptoms or retardation. 2/33 patients died during follow up (1 ischemic stroke from Pulmonary AVF, 1 death despite partial embolisation). CONCLUSION: Cerebral arteriovenous fistulae are a rare disease, but not infrequently seen in neonates and infants with AVMs. In one fourth of these patients HHT is suspected to be present. The AVFs are always superficial and fed by pial (cortical) arteries. They seldom reveal a hemorrhagic event. They are similar to those encountered in the posterior fossa or spinal cord. Endovascular treatment using NBCA was the treatment modality chosen resulting in a high rate of success and allowing children to grow up normally with no hemorrhages on follow up and no new symptom other than those already present on admission.

Adolescent↗
PubMed2005

[Varicella, acute postinfectious arteriopathy and cerebral arterial thrombosis in childhood: a unique clinical and etiologic framework to be fully acknowledged].

Acute arteriopathies are the etiological factor of 25% of all the cerebral arterial thrombosis cases in childhood; they give way to ischemic strokes which have specific clinical and radiological features; varicella is the etiologic factor in 60% of the cases; favorable outcome is the rule; physiopathology and treatment remain under discussion.

Acute Disease↗
PubMed2004

Posterior cranial fossa single-hole arteriovenous fistulae in children: 14 consecutive cases.

We report 14 consecutive children with 23 posterior cranial fossa arteriovenous fistula (AVF); six had multifocal lesions, involving the supratentorial brain in three and the spinal cord in one. There were two boys and four girls with a family history compatible with hereditary haemorrhagic telangiectasia. The diagnosis was made in infancy in eight cases and in a further six before the age of 12 years; mean age at diagnosis was 3.5 years. The male-to-female ratio was 1.8:1. Presenting features were macrocrania in four cases, haemorrhage or headache in three and nonhaemorrhagic neurological deficits or and cardiac overload in two. Dominant supply to the symptomatic fistula arose from the posterior inferior cerebellar artery in five cases, anterior inferior cerebellar artery in two and the upper basilar artery system in seven. All children were primarily treated by transarterial embolisation. We treated thirteen children (93%) by transarterial embolisation alone; one older child with a history of haemorrhage also underwent radiosurgery. We obtained 100% exclusion of the fistula(e) in six children, 95-80% in five, 80-50% in one and <50% in one. Of the incompletely treated cases, three had conservative management, and two with 80% and one with 60% reduction of their lesion are scheduled for elective treatment; two partially treated case died. There was no morbidity due to the endovascular procedures. Follow-up since referral is 6 months-10 years (mean 4.5 years). Ten children are neurologically normal, two have persistent (pre-existing) neurological deficits and two are dead.

Arteriovenous Fistula↗
PubMed2004

Bilateral segmental regression of the carotid and vertebral arteries with rete compensation in a Western patient.

We report a case of symptomatic symmetrical, bilateral absence of the cavernous internal carotid (ICA) and transdural vertebral artery (VA) segments with formation of a rete mirabile. There have been similar reports in Asian patients; ours is the first in the Western population. A 29- year-old woman presented with recurrent temporary blindness and an episode of minor subarachnoid haemorrhage. Angiography demonstrated absence of the C5 and C6 segments of the ICA and the C1/2 segments of the VA bilaterally, with typical carotid rete mirabile formation to reconstitute the distal flow. Comparative anatomy and embryology show retia in several species and point to their secondary origin. The anomalies of the ICA cannot be called agenesis but rather absence since they are likely to result from perinatal disappearance of the artery rather its failure to develop.

Adult↗
PubMed2004

Angio-architecture of spinal cord arteriovenous shunts at presentation. Clinical correlations in adults and children. The Bicêtre experience on 155 consecutive patients seen between 1981-1999.

OBJECTIVE: To analyse possible relationships between the symptoms and signs created by intradural spinal cord arteriovenous shunts (SCAVSs) and their angio-architecture. METHODS: The clinical and radiological files of 155 patients, both adults and children, seen between 1981 and 1999 with a SCAVS were retrospectively reviewed. SCAVSs were divided into nidus type (small superficial or large intramedullary), and fistulas (micro (mAVFs)- or macrofistulas (MAVFs)). The angio-architectural points studied were arterial stenosis, proximal arterial aneurysm, distal arterial aneurysm, arteriovenous fistulas, pial venous drainage and/or reflux, venous ectasias, venous stenosis, venous thrombosis, false aneurysms. Correlations between architecture, location, age groups and symptoms and signs were made. FINDINGS: A male predominance was noted in both adults and children. Most of the lesions were located at the thoracic level, but hemorrhage occurred as the presenting event predominantly in cervical localizations. 30 patients (20 AVMs; 4 mAVFs, 6 MAVFs) were children. 5 of the 6 MAVFs found in children were associated with Hereditary Hemorrhagic Telengiectasia (HHT1). Twenty one children (70%) had bled. Spontaneous total or subtotal recovery was the rule in 15 of those who had bled (72%) but early recurrent hemorrhages occurred in 2. Among 125 adults 56 presented with hemorrhage (45%). The proportions of those who recovered spontaneously (71%) or rebled (3,6%) in the same year after the initial episode were very similar to children. All other adults presented with acute or progressive non-hemorrhagic episodes. There was no significant difference in the angio-architecture between hemorrhagic and non hemorrhagic SCAVS, except for that occurrence of pseudo-aneurysms. Hemorrhage in SCAVSs may not be exclusively due to haemodynamic factors. Venous congestion was responsible for progressive symptoms. Acute deficits unrelated to bleeds were due to intralesional thrombosis or hemodynamic changes. INTERPRETATION: The short term prognosis of hemorrhagic SCAVSs is good, and there is no need for emergency treatment. MRI delineates the cord and makes the diagnosis of the lesion but angiography remains the gold standard for analysis of the vasculature. The angio-architecture reflects the ageing of the lesion but there is not a precise correlation between angio-architecture and clinical symptoms, except for pseudoaneurysms which relate to the hemorrhagic portion of the lesion.

Adolescent↗
PubMed2004

MR perfusion imaging in proliferative angiopathy.

Seizures, which may be the main expression of cerebral arteriovenous malformations (CAVM) can be difficult to control medically. Our goal was to use perfusion-weighted imaging (PWI) in correlation with clinical data to detect abnormal areas of the cerebrum related to a particular type of CAVM (proliferative angiopathy) and to study the pathophysiology. We use PWI, with a bolus injection of contrast medium, to investigate seven patients with proliferative angiopathy and fits producing language disturbance. Perfusion parameters were calculated using the first-pass moment theory. Five patients had perimalformative and/or contralateral abnormal areas with relative hyperperfusion (cerebral blood volume +20.7+/-16.2%, blood flow 92.5+/-68.8 ml/min/100 g). Areas of hypoperfusion and venous congestion were detected in two patients. One patient who underwent MRI after a severe focal deficit had no significant haemodynamic abnormality.

Adolescent↗
PubMed2004

Acute epiglottitis: MRI.

We report the MRI findings in an adult with epiglottitis. There was thickening of the epiglottis and left aryepiglottic fold. Management of this life-threatening condition requires imaging only when the diagnosis is uncertain or when an abscess or other complication is suspected.

Abscess↗
PubMed2004

[Lung separation after reintubation with airway exchange catheter in multiple trauma patient with massive haemoptysis].

A 24-year-old man fell from the third floor. He developed an unilateral pulmonary parenchymal injury and a significant haemoptysis following blunt thoracic trauma. Because of its abundance, it was not possible to obtain adequat oxygenation. To protect controlateral lung from inhalation and to achieve adequat oxygenation, we used double lumen endotracheal tube, lung separation and one lung ventilation. To solve potential airway management difficulties (haemorrhage, trauma, cervical immobilization), we used airway exchange catheter (Cook) to place the double lumen endotracheal tube. Haemoptysis has been controlled by embolization of the right bronchial artery.

Accidental Falls↗
PubMed2004

[Neonatal thrombosis of the jugular veins: long-term repercussions on cerebral development (two cases)].

Bilateral obstruction of the internal jugular veins is rare in the neonatal period and no long-term follow-up has been reported yet. We report two cases. The first developped an extensive thrombosis of superior veina cava related to a central veinous line, the second an unilateral thrombosis of the transverse-sigmoid sinus associated to a constitutional hypoplasia of the contralateral jugular vein. In the latter case, no cause or risk factor was noticeable, except for a forceps delivery. In both cases the clinical course was dominated by the development of a prominent collateral network of cervico-facial veins and by a progressive macrocrania. According to MRImaging, the latter was not related to a dilation of CSF spaces, but to a macro-encephaly, either by inflation of the vascular veinous compartment inside the parenchyma or by genuine brain's overgrowth. Long-term follow-up showed a grossly normal course, both from the neurological and the scholar point of view. However, slight neuropsychological anomalies were noticed, bringing some shade on the prognosis.

Brain↗
PubMed2004

[Diffusion, perfusion and activation functional MRI studies of brain arteriovenous malformations].

The management of Brain Arteriovenous Malformations continues to be challenged by a lack of understanding and control of pathophysiological processes implied in the clinical symptoms. New data from functional MRI with diffusion-weighted, perfusion-weighted and neuronal activation highlight abnormal brain areas near or remote to the AVM nidus. Moreover, these techniques are able to show hemodynamic and neuronal adaptative phenomena involved in brain plasticity. They reflect the instantaneous hemodynamic brain conditions that may help to correlate the clinical symptoms with the anatomical and functional substratum and to influence any invasive therapy.

Brain↗