D. Sirinelli

Prospective evaluation of time-of-flight MR angiography in the follow-up of intracranial saccular aneurysms treated with Guglielmi detachable coils

PURPOSE The purpose of our study was to prospectively evaluate 3D time-of-flight (TOF) MR angiography (MRA) in the follow-up of 27 intracranial aneurysms treated with Guglielmi detachable coils (GDCs). METHOD From February 1997 to June 1998, 26 patients with 27 aneurysms were included in this prospective study. Aneurysms were located in the anterior circulation in 23 cases and in the posterior circulation in 4 cases. All patients underwent 3D TOF MRA and digital subtraction angiography (DSA) in the same week within 4 months after aneurysmal treatment with GDCs. No clinical events occurred during the follow-up. We analyzed residual flow within the coil mass and within the aneurysmal neck and the patency of the parent and adjacent arteries on MRA and DSA. MRA analysis was based upon MIPPED and source images. DSA was our gold standard. RESULTS In all cases, the quality of MRA was good enough to be informative. In aneurysmal analysis, the sensitivity, specificity, positive predictive value, and negative predictive value of MRA were, respectively, 80, 100, 100, and 96% to diagnose residual flow within the coil mass (one false-negative case) and 83, 100, 100, and 95.5% to diagnose residual flow within the aneurysmal neck (one false-negative case). In arterial analysis, sensitivity and positive predictive value of MRA were 89 and 100% to diagnose patency of the parent artery (three false-negative cases) and 83 and 100% to diagnose patency of adjacent arteries (seven false-negative cases). CONCLUSION In the follow-up of intracranial aneurysms treated with GDCs, 3D TOF MRA could be used as a screening test to select patients that should undergo DSA and thus could improve patient follow-up in terms of risk-benefit.

Thalamo-Striatal T2-Weighted Hyperintensities (Unidentified Bright Objects) Correlate With Cognitive Impairments in Neurofibromatosis Type 1 During Childhood

Learning disabilities represent the main childhood complication in neurofibromatosis type 1 (NF1). Patients frequently exhibit T2-weighted hyperintensities called unidentified bright objects (UBOs) on brain magnetic resonance imaging (MRI), with unclear relationship to such cognitive disabilities. This study aimed to determine whether thalamo-striatal UBOs correlate with cognitive disturbances. Thirty-seven NF1 children were studied: 24 with UBOs (18 of which were thalamo-striatal UBOs), and 13 without UBOs. NF1 subjects carrying thalamo-striatal UBOs had significantly lower IQs and visuospatial performances than those without UBOs in this location. These results suggest that UBOs may contribute to NF1 cognitive impairments through thalamo-cortical dysfunction.

Malformations corticales et épilepsie: apport de l'IRM.

Objectifs Les malformations corticales sont de plus en plus reconnues comme d’importantes causes d’epilepsie, de retard mental et autres troubles neurologiques. Notre but est de presenter l’interet de l’IRM dans ces pathologies en y associant leurs aspects cliniques, genetiques et therapeutiques. Materiels et methodes La classification utilisee est celle proposee en 2001 par Barkovich et al. Cette classification est basee sur les trois evenements fondamentaux de la formation corticale : proliferation des neurones et de la glie dans la matrice germinale subventriculaire, migration des neurones post-mitotiques vers la peripherie, organisation corticale secondaire en 6 couches. Resultats L’IRM etudie tout particulierement l’epaisseur du manteau cortical, la morphologie du cortex et des sillons, la jonction SB-SG, recherche la presence de tissu gris en position ectopique. Ces informations, couplees avec l’histoire familiale, la semiologie des crises et les donnees genetiques doivent permettre une classification correcte des lesions. Conclusion L’IRM permet le depistage et la classification des malformations corticales. Son apport est fondamental pour decider de la possibilite d’une chirurgie en cas d’epilepsie refractaire au traitement medical. Une correcte classification de ces malformations devrait aider a fournir a la famille un conseil adapte a la fois en terme de genetique et de pronostic.

Repères échographiques de gyration cérébrale fœtale normale

Resume Objectifs Preciser les reperes de la gyration en echographie et leur chronologie d’apparition en les confrontant aux donnees de la maturation cerebrale disponibles en foeto-pathologie et IRM. Patients et methodes Grâce a une etude prospective, 158 cerveaux fœtaux normaux entre 21 et 34 semaines d’amenorrhee ont ete analyses de facon standardisee par echographie sus-pubienne sur onze coupes dans les plans axial, coronal et sagittal. Resultats Le developpement sequentiel des differents sillons et scissures du cortex cerebral a ete decrit en fonction de l’âge gestationnel. Cette chronologie etait en accord avec les references anatomo-pathologiques avec un retard moyen d’une semaine et en accord sans retard avec l’IRM. L’iconographie a pu etre presentee sur un site Internet: http://www.gyration-foetale.fr . Conclusion Cette etude echographique fournit des reperes et une iconographie precis de la gyration cerebrale fœtale normale. L’analyse et la connaissance de cette gyration contribuent a mieux apprehender la maturation du cortex cerebral et a suspecter une pathologie de l’encephale en cas d’anomalie.

Proton MR spectroscopic imaging of basal ganglia and thalamus in neurofibromatosis type 1: correlation with T2 hyperintensities

IntroductionNeurofibromatosis type 1 (NF1) is frequently associated with hyperintense lesions on T2-weighted images called “unidentified bright objects” (UBO). To better characterize the functional significance of UBO, we investigate the basal ganglia and thalamus using spectroscopic imaging in children with NF1 and compare the results to anomalies observed on T2-weighted images.MethodsMagnetic resonance (MR) data of 25 children with NF1 were analyzed. On the basis of T2-weighted images analysis, two groups were identified: one with normal MR imaging (UBO− group; n = 10) and one with UBO (UBO+ group; n = 15). Within the UBO+ group, a subpopulation of patients (n = 5) only had lesions of the basal ganglia. We analyzed herein seven regions of interest (ROIs) for each side: caudate nucleus, capsulo-lenticular region, lateral and posterior thalamus, thalamus (lateral and posterior voxels combined), putamen, and striatum. For each ROI, a spectrum of the metabolites and their ratio was obtained.ResultsPatients with abnormalities on T2-weighted images had significantly lower NAA/Cr, NAA/Cho, and NAA/mI ratios in the lateral right thalamus compared with patients with normal T2. These abnormal spectroscopic findings were not observed in capsulo-lenticular regions that had UBO but in the thalamus region that was devoid of UBO.ConclusionMultivoxel spectroscopic imaging using short-time echo showed spectroscopic abnormalities in the right thalamus of NF1 patients harboring UBO, which were mainly located in the basal ganglia. This finding could reflect the anatomical and functional interactions of these regions.

Efficacy and safety of embolization in arteriovenous malformations of the extremities and head and neck: a retrospective study of 32 cases

BackgroundDefinitive treatment of arteriovenous malformations (AVMs) consists of complete surgical excision. When not possible, embolization may be performed.ObjectivesWe aimed to evaluate the efficacy and safety of embolization forAVMs of the extremities and head and neck.Materials and methodsThis retrospective study included all patients undergoing embolization for AVMs of skin and soft tissues on the limbs, head and neck, in the University Hospital Center of Tours between January 1996 and December 2009. The main outcome was efficacy, assessed by two independent assessors, as the percentage of AVM devascularized at the end of embolization. Secondary outcomes were patient satisfaction, evolution of symptoms and safety of embolization.ResultsWe included 32 AVMs in 31 patients, for 66 embolizations evaluated. In 18 AVMs (56.3%), devascularization was greater than 75% of the initial vascularization. Efficacy was lower for AVMs of the upper limbs than other body parts (p = 0.003). For 18 patients who could be contacted by telephone, the mean global satisfaction was 6.0 ± 2.7 on a scale of 0 to 10, and 13 (72.2%) reported an improvement of the symptoms linked to the AVM. Severe adverse events were reported after 4 embolizations, all located on the head and neck.ConclusionEmbolization can lead to good devascularization and improve symptoms linked to AVMs, especially in lower limbs. Minor complications are frequent, and severe adverse events may occur, especially after procedures on the head and neck.

Imagerie des malformations anorectales en période néonatale

Imaging of anorectal malformations in the neonatal period Purpose. The classification of anorectal malformations (ARM) as high or low is based on clinical and anatomical characteristics. It has an impact on the surgical management but also on the functional prognosis. In the absence of consensus, our goal was to determine the value of imaging in the neonatal period for diagnosis and management of infants with ARM. Materials and methods. Retrospective study of 43 infants imaged over a 9 year period. The different imaging studies (abdominal and pelvic ultrasound, radiographs, percutaneous opacifications and fistulograms) performed for each infant were collected and analyzed then correlated to clinical and surgical findings. Results. Clinical evaluation could classify 30 ARM as low and 4 ARM as high while 9 ARM without fistula remained indeterminate. Imaging findings were mixed: on ultrasound, the rectal cul-de-sac to perineum distance did not appear to be determinant, contrary to published data. Pelvimetry showed limitations, irrespective of the technique. Morphological evaluation provided the following data: presence of fistula, sphincter anatomy, rectal cul-de-sac to perineum distance. Conclusion. Classification relies on clinical evaluation in most cases. Opacification techniques and ultrasound remain useful in some cases. MRI could become the preferred imaging modality.

Déformation de Madelung de l’enfant liée à la présence d’un ligament radio-lunaire anormal : à propos de 4 cas

Resume Objectif Preciser l’apport du scanner et de l’IRM du poignet dans la mise en evidence d’un ligament radiolunaire anormal qui participerait a la deformation de Madelung et souligner l’interet de l’analyse radiographique initiale qui evoque la presence de ce ligament. Observations et resultats Les auteurs rapportent les cas de quatre adolescentes qui ont consulte pour des douleurs uni ou bilaterales des poignets. Les radiographies standards ont montre une deformation de Madelung, isolee, avec une incurvation excessive radiocubitale inferieure et un aspect triangulaire des epiphyses avec fermeture de l’angle radiocarpien. Chaque adolescente a beneficie soit d’une tomodensitometrie helicoidale sans injection, soit d’un arthroscanner ou d’une imagerie par resonance magnetique. Toutes ces techniques identifierent un ligament radiolunaire anormal dont l’insertion radiale se fait au sein d’une gouttiere osseuse. A posteriori cette gouttiere radiale apparaissait sur les radiographies standards. Dans deux cas, l’exerese de ce ligament a permis une diminution de la deformation et de la symptomatologie, sans recourir a l’osteotomie classique. Conclusion Dans le cadre de la deformation de Madelung, une imagerie par tomodensitometrie ou mieux par IRM, non irradiant et sans injection detecte la presence d’un ligament radiolunaire anormal au sein d’une gouttiere radiale. La visualisation de cette gouttiere par la radiographie standard suggere indirectement la presence de ce ligament, dont l’exerese precoce semble limiter la deformation du poignet, ameliorer sa mobilite et soulager la douleur.

Un torticolis spasmodique lié à la prise de métoclopramide: une cause rare de pseudoluxation rotatoire C1-C2 chez l’enfant

Resume Tout torticolis de l’enfant doit faire rechercher une origine traumatique. D’autres etiologies peuvent etre en cause. Les auteurs rapportent un cas de pseudoluxation rotatoire atloido-axoidienne (PRAA) medicamenteuse chez un enfant. L’anamnese retrouvait la notion d’une chute avec traumatisme crânien le matin meme suivie de cephalees. La clinique notait une rotation cervicale droite irreductible douloureuse, une hyperreflexie osteotendineuse. Un aspect de « luxation » C1-C2 sans lesion traumatique etait revelait par la tomodensitometrie du rachis cervical. En quelques heures, le torticolis s’est reduit spontanement puis est reapparu a gauche. Cette fluctuation clinique associee a la prise de metoclopramide (Primperan®) initiee plus tot pour une gastroenterite aigue faisait porter le diagnostic de PRAA. Cette entite, confirmee par une evolution clinicoradiologique favorable, est favorisee par l’hyperlaxite ligamentaire de la jonction crâniorachidienne de l’enfant. L’analyse de l’imagerie et la recherche systematique de causes toxiques ont permis d’en faire le diagnostic.

Diagnosis of Sjögren-Larsson syndrome by magnetic resonance spectroscopy.

A 25-month-old girl had been born, after an uneventful pregnancy, at 36 weeks of gestation. Her weight was low for her gestational age (2025 g). She was the first child of unrelated and healthy parents. She presented with marked congenital ichthyosis. Motor retardation was later observed (i.e., stable sitting and walking at ages 12 and 22 months, respectively). Her speech was also delayed. Her first clinical evaluation at age 25 months revealed hyperkeratotic ichthyosis, especially at the main flexor folds, with mild facial involvement. The girl manifested severe pruritus. Her hair, nails, and teeth were normal. No organomegaly was evident. A neurologic examination indicated spastic quadriplegia with axial hypotonia and a left convergent strabismus. Cranial magnetic resonance imaging and proton magnetic resonance spectroscopy were performed with a 1.5 T Signa HDXt scanner (General Electric Medical Systems, Milwaukee, WI) (echo times, 35 ms and 144 ms; repetition time, 1500 ms; volume of interest, 8 mL). Cranial magnetic resonance imaging indicated abnormal, hyperintense signals on T2-weighted sequences in the subcortical white matter, predominantly in periventricular areas (Fig 1A). Magnetic resonance spectra were analyzed in the parietal subcortical white matter (Fig 1B), and at various echo times indicated two abnormal peaks compatible with lipid content: one broad and small peak at 0.9 parts per million corresponding to CH3 lipids of the methyl group, and one high and sharp peak at 1.3 parts per million corresponding to (CH2)n lipids of the methylene group (Fig 1C,D). The remaining peaks for N-acetyl aspartate, creatine, choline, and myoinositol appeared normal in shape and relative proportions. The association of congenital ichthyosis with pruritus, spastic tetraplegia, mental retardation, and white-matter hyperintensities on magnetic resonance imaging was highly suggestive of Sjogren-Larsson syndrome. Fibroblast fatty aldehyde/NADþ oxidoreductase activity was not detectable, confirming our diagnosis of Sjogren-Larsson syndrome.