Evaluer la faisabilité et les résultats de l’IRM squelette entier comparée à la scintigraphie osseuse en cancérologie. Soixante-dix patients suivis en oncologie pour douleur ou augmentation des marqueurs ont bénéficié d’une IRM squelette entier (séquences Tl et STIR avec composing, Siemens avanto) en 13 mois. Vingt patients ont eu une scintigraphie osseuse dans les 2 mois précédents. Nous avons évalué la faisabilité et les résultats préliminaires de l’IRM squelette entier par rapport à la scintigraphie osseuse. En moins de 30 minutes, 69/70 patients ont supporté l’examen complet. Dans 14 cas, il existe une bonne corrélation avec la scintigraphie même si l’IRM montrait plus de lésions dans 3 cas. Dans 2 cas, nous rapportons une discordance avec une scintigraphie normale et une IRM positive confirmée par l’évolution clinique. Dans 4 cas, l’IRM a permis de rectifier le diagnostic (1 paget, 1 PASH, 1 tassement bénin et 1 nécrose de hanche). Nous illustrons les pièges et les avantages de l’IRM : tout hypersignal STIR n’est pas une métastase. Découverte fortuite d’anomalies extra-osseuses (métastases cérébrales ou hépatiques.). l’IRM squelette entier est faisable en pratique cancéro-logique quotidienne en moins de 30 minutes et pourrait être une alternative à la scintigraphie osseuse.

Description des différents aspects des dissection des artères cervicales (DAC) en IRM et en angioscanner (AS). Apport et comparaison des deux techniques. A partir de notre expérience et des données de la littérature, nous rapportons l’intérêt de TAS (16 barrettes, Siemens) et de l’IRM (Séquence Tl avec saturation de graisse, ARM avec gadolinium (ARMG)) (1,5 T, Siemens) dans le diagnostic des DAC. La présentation comprend : a) une brève description de l’histoire naturelle des DAC, b) une illustration des différents aspects morphologiques dans les localisations carotidiennes et vertébrales, c) les difficultés diagnostiques rencontrées en IRM et en AS. D) une comparaison entre l’IRM et l’AS, e) les principaux diagnostics différentiels. Les accidents ischémiques du sujet de moins de 45 ans doivent faire rechercher systématiquement une DAC. Le principal avantage de l’IRM, outre l’évaluation parenchymateuse cérébrale, est la mise en évidence de l’hématome de la paroi vasculaire. En revanche les signes angiographiques sont mieux visualisés en AS.

We report the case of a 67 year old patient admitted at our institution for acute onset of left hemiplegia. MRI was done 2 h 30 after symptom onset. Diffusion weighted images showed a hyperintense lesion in the right basal ganglia region with restricted apparent diffusion coefficient (ADC=428. 10(-6) mm(2)/s), a 50% decrease in value compared to the normal left side, consistent with acute ischemia. The lesion was hyperintense and moderately heterogeneous at FLAIR imaging, best seen on echo planar T2W images, with hypointense rim consistent with magnetic susceptibility artifact. The appearance and location of the lesion suggested the possibility of hematoma, which was confirmed at CT. Interpretation of ADC values must be performed in correlation with results at imaging including sequences sensitive to magnetic susceptibility artifacts such as echo planar T2*W and T2W sequences in order to exclude the possibility of underlying hematoma.

PURPOSE To prospectively compare dynamic three-dimensional (3D) gadolinium-enhanced magnetic resonance (MR) angiography and digital subtraction angiography (DSA) for the detection of ostial stenosis of the craniocervical vessels. MATERIALS AND METHODS Thirty-three patients with carotid stenosis of more than 50% at sonography prospectively underwent both MR angiography and DSA. The overall quality of each DSA and MR angiographic study was analyzed. For each craniocervical vessel (brachiocephalic, common carotid, subclavian, and vertebral arteries) (n = 231), ostial stenosis was graded as follows: normal, mild (<50%), moderate to severe (>50%), or occlusion. MR angiographic and DSA results were compared by means of the Spearman rank correlation coefficient (Rs). RESULTS The overall diagnostic quality of MR angiography was excellent or adequate. Three studies were inadequate because of a poor signal-to-noise ratio (13 of 231 arteries) or a coverage error (five of 231 arteries). Findings at MR angiography and DSA agreed on the degree of stenosis (Rs = 0.82, P <.001). No cases of stenosis of more than 50% were missed at MR angiography. However, some discrepancies were noted between vertebral arteries and the other craniocervical vessels. The sensitivity and specificity for stenosis of more than 50% in other craniocervical vessels were 100% and 98%, respectively. The sensitivity and specificity for stenosis of more than 50% in the vertebral arteries were 100% and 85%, respectively. Findings at MR angiography tended to result in overestimation of the degree of ostial stenosis, especially in vertebral arteries (10 [15%] of 66 arteries). CONCLUSION MR angiography is useful to rule out ostial stenosis of the craniocervical vessels. MR angiography is an adequate diagnostic tool for ostial stenosis, except in the vertebral artery.

A patient with right-sided L5 sciatica and low back pain experienced a symptom recurrence 3 weeks after surgical removal of a right-sided L4-L5 disk herniation. Magnetic resonance imaging (MRI) was suggestive of recurrent disk herniation and showed enhancement of the right L5 root. This case emphasizes the difficulties met in interpreting imaging studies done too early after surgery.

PURPOSE:To prospectively compare gadolinium-enhanced magnetic resonance (MR) angiography and computed tomographic (CT) angiography with digital subtraction angiography (DSA) for use in detecting atheromatous stenosis and plaque morphology at the carotid bifurcation.MATERIALS AND METHODS:Forty-four carotid arteries (in 22 patients) were analyzed by using CT angiography, enhanced MR angiography, and DSA. CT and enhanced MR angiograms were reconstructed with maximum intensity projection and multiplanar volume reconstruction. The following four features were analyzed: degree of stenosis on the basis of North American Symptomatic Carotid Endarterectomy Trial criteria, length of stenosis, luminal surface, and presence of ulcers.RESULTS:There was significant correlation between CT angiography, enhanced MR angiography, and DSA for degree and length of stenosis. With enhanced MR angiography and CT angiography, degree of stenosis was underestimated in two of 44 cases. No case of overestimation with CT angiography was found. Severe internal carotid artery stenoses were detected with high sensitivity and specificity: 100% and 100%, respectively, with CT angiography; 93% and 100%, respectively, with enhanced MR angiography. Luminal surface irregularities were most frequently seen at CT angiography. With CT angiography and enhanced MR angiography, more ulceration was detected than with DSA.CONCLUSION:There was a significant correlation between CT angiography, enhanced MR angiography, and DSA in evaluation of carotid artery stenosis. Enhanced MR angiography or CT angiography can be used to adequately evaluate carotid stenosis.

Nous rapportons l’observation d’un patient présentant une lombosciatalgie L5 droite récidivant trois semaines après la cure chirurgicale d’une hernie discale L4–L5 droite. L’imagerie par résonance magnétique (IRM) a révélé un aspect évocateur de récidive de hernie discale, avec prise de contraste de la racine L5 droite. Cette observation permet de discuter ces deux aspects et de rappeler les pièges d’une imagerie trop précoce après intervention.

Ostial stenosis of the craniocervical vessels are frequently associated with carotid stenosis. Consequently, exploration of the aortic arch is necessary prior to carotid endarterectomy. Contrast-enhanced MR angiography, (gRMA) could replace digital substraction angiography (DSA). The goal of this work was to evaluate gRMA for the detection of ostial stenosis of the craniocervical vessels. Twenty two patients with carotid stenosis > 50 % oil sonography examination prospectively underwent gRMA and DSA. We analyzed the overall quality of each gRMA and the degree of ostial stenosis of the craniocervical vessels (innominate, left carotid, subclavian and vertebral arteries). Thirteen gRMA examination was considered as good quality and 8 as adequate for diagnosis. There was significant correlation between gRMA and DSA for degree of stenosis (k = 0,82, p < 0,0001). gRMA tends to overestimate degree of ostial stenosis, especially for vertebral arteries. We conclude that gRMA is a promising tool but cannot yet be used as a stand-alone procedure for the evaluation of ostial stenosis of the cranlocervical vessels.

Ostial stenosis of the craniocervical vessels are frequently associated with carotid stenosis. Consequently, exploration of the aortic arch is necessary prior to carotid endarterectomy. Contrast-enhanced MR angiography (gRMA) could replace digital substraction angiography (DSA). The goal of this work was to evaluate gRMA for the detection of ostial stenosis of the craniocervical vessels. Twenty two patients with carotid stenosis > 50% on sonography examination prospectively underwent gRMA and DSA. We analyzed the overall quality of each gRMA and the degree of ostial stenosis of the craniocervical vessels (innominate, left carotid, subclavian and vertebral arteries). Thirteen gRMA examination was considered as good quality and 8 as adequate for diagnosis. There was significant correlation between gRMA and DSA for degree of stenosis (k = 0.82, p < 0.0001). gRMA tends to overestimate degree of ostial stenosis, especially for vertebral arteries. We conclude that gRMA is a promising tool but cannot yet be used as a stand-alone procedure for the evaluation of ostial stenosis of the craniocervical vessels.

BACKGROUND AND PURPOSE:The natural history of aneurysmal forms of cervical artery dissection (CAD) is ill defined. The aims of this study were to assess (1) clinical and anatomic outcome of aneurysmal forms of extracranial internal carotid artery (ICA) and vertebral artery (VA) dissections and (2) factors associated with aneurysmal forms of CAD.METHODS:Seventy-one consecutive patients with CAD were reviewed. Aneurysmal forms of CAD were identified from all available angiograms by 2 neuroradiologists. The frequency of arterial risk factors, of multiple vessel dissections, and of artery redundancies was compared in patients with and without aneurysm. Patients with aneurysm were invited by mail to undergo a final clinical and radiological evaluation.RESULTS:Of the 71 patients, 35 (49.3%) had a total of 42 aneurysms. Thirty aneurysms were located on a symptomatic artery (ICA, 23; VA, 7) and 12 on an asymptomatic artery (ICA, 10; VA, 2). Patients with aneurysm had multiple dissections of cervical vessels (18/35 versus 7/36; P:=0.005) and arterial redundancies (20/35 versus 11/36; P:=0.02) more frequently than patients without aneurysm. They were also more often migrainous (odds ratio=2.7 [95% CI, 0.8 to 8.5]) and tobacco users (odds ratio=2.2 [95% CI, 0.7 to 6.3]). Clinical and anatomic follow-up information was available for 35 (100%) and 33 patients (94%), respectively. During a mean follow-up of >3 years, no patient had signs of cerebral ischemia, local compression, or rupture. At follow-up, 46% of the aneurysms involving symptomatic ICA were unchanged, 36% had disappeared, and 18% had decreased in size. Resolution was more common for VA than for ICA aneurysms (83% versus 36%). None of the aneurysms located on an asymptomatic ICA had disappeared.CONCLUSIONS:Although aneurysms due to CAD frequently persist, patients carry a very low risk of clinical complications. This favorable clinical outcome should be kept in mind before potential harmful treatment is contemplated.

We report a case of 54 year old patient harboring a solitary painless mass of the calvarium. There was a well-defined biparietal lytic lesion on plain skull radiographics. Computed tomography showed a large hyperdense lesion. This lesion was extraaxial and nearly isointense with gray matter on T1 and T2-weighted MR images, and diffusely enhanced after gadolinium injection Angiography showed hyperovascularity supplied by middle meningeal and superficial temporal arteries. Imaging study bore some similarities to meningioma. A large extra-axial mass with an important lytic lesion should have led to the diagnosis of plasmocytoma.

We report a case of 54 year old patient harboring a solitary painless mass of the calvarium. There was a well-defined biparietal lytic lesion on plain skull radiographics. Computed tomography showed a large hyperdense lesion. This lesion was extraaxial and nearly isointense with gray matter on T1 and T2-weighted MR images, and diffusely enhanced after gadolinium injection. Angiography showed hyperovascularity supplied by middle meningeal and superficial temporal arteries. Imaging study bore some similarities to meningioma. A large extra-axial mass with an important lytic lesion should have led to the diagnosis of plasmocytoma.

We report an interesting transparency study using a volume-rendering technique applied to CT angiography in a patient with a sylvian aneurysm. On a single view, all the information required for the aneurysmal treatment could be analyzed. Comparison with maximum intensity projection and virtual endoscopy reconstructions was performed.

PURPOSE:Motion artifacts of the ascending aorta may impair image quality and simulate an intimal flap or a false channel. The purpose of this study is to evaluate the prevalence, amplitude, and extent of motion artifacts of the aorta in spiral CT and to specify the effects of acquisition and reconstruction parameters on these artifacts.METHOD:One hundred seventy-one thoracic spiral CT examinations were retrospectively analyzed by two reviewers. The analysis sought to determine the presence, location, amplitude, and extent of artifacts of the ascending aorta.RESULTS:Aortic artifacts were detected on spiral CT in 57% of cases. The mean amplitude and mean extent were 4+/-4 and 6+/-7 mm, respectively. Artifacts in the ascending aorta were significantly higher with the 360 degrees linear interpolation (LI) algorithm than with the 180 degrees LI algorithm.CONCLUSION:The prevalence of motion artifacts on spiral CT is higher in this study than the reported prevalence in incremental CT. However, this higher prevalence is significantly reduced when the 180 degrees LI algorithm is used.