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The field of cardiovascular MRI has evolved rapidly over the past decade, feeding new applications across a broad spectrum of clinical and research areas. Advances in magnet hardware technology, and key developments such as segmented k-space acquisitions, advanced motion encoding techniques, ultra-rapid perfusion imaging and delayed myocardial enhancement imaging have all contributed to a revolution in how patients with ischemic and non-ischemic heart disease are diagnosed and treated. Actually, cardiac MRI is a widely accepted method as the "gold standard" for detection and characterization of many forms of cardiac diseases. The aim of this review is to present an overview of cardiac MRI technology, advances in clinical applications, and future directions.

We report the case of a man presenting with a Pierre Marie-Bamberger syndrome. This paraneoplastic syndrome revealed an undifferentiated intracardiac sarcoma. This case emphasizes the need for multimodality imaging to characterize intracardiac tumor.

The purpose of this article is to present a brief theoretical review of the models characterizing delayed myocardial enhancement applicable to both MR and CT imaging, review the different characteristics of commercially available gadolinium-based and iodinated contrast materials, and summarize the literature on the potential value of dedicated MR imaging contrast currently in development for the diagnosis of myocardial viability. The intensity of myocardial enhancement following infarction is related to two factors: expansion of the interstitial volume (15+/-2% in normal myocardium and 80+/-3% within necrosis) secondary to cell necrosis and perfusion abnormalities due to the absence of revascularization or lesions to the microcirculation. A kinetic model of contrast material properties within myocardium could be constructed from Kety's equation with regards to enhancement within the different myocardial tissues (viable myocardium, necrotic myocardium, fibrosis, no-reflow zones, stunned or hibernating myocardium). This model can be applied to both CT and MR since clinically available contrast agents are extracellular, inert and kinetically comparable. The development of dedicated contrast agents for viability and necrosis or molecular contrast agents open new horizons for preclinical research.

It is becoming increasingly desirable to diagnose ankylosing spondyloarthropathy (AS) at its pre-radiographic stage (prior to the presence of sacro-iliitis on radiographs). MRI plays a key role for early diagnosis of AS, as illustrated by recently proposed international diagnostic criteria (ASAS). MRI of the SI joints is most helpful for early diagnosis; sequences using fat suppression and/or Gadolinium administration are necessary for the detection of inflammatory changes. However, the rate of false positive and false negative results of MR imaging of the SI joints, especially early in the course of the disease, is unknown and requires prudent interpretation of imaging findings. In patients with normal MRI examination of the SI joints and/or if symptoms are limited to the spine, MRI of the lumbar spine with STIR and/or Gadolinium administration may be helpful; again the positive and negative predictive values are unknown, especially early in the course of the disease. The demonstration of inflammatory changes on MRI, at the axial level, could be an indication for anti-TNF treatment, outside of WMA (national and international recommendations). The role of Doppler US, especially for peripheral entheses, remains hypothetical for early diagnosis. The role of MRI for structural evaluation is also being assessed even though radiographs remain the standard of reference. To date, no treatment, conventional or other, has been shown to have a structural effect (aside from limitations related to the methodology of available studies).

Ankylosing spondylitis is the most common spondyloarthropathy. It is characterized by enthesopathy (inflammation at the insertion of ligaments, tendons or fascia to bone). The os calcis is most frequently involved. Additional peripheral manifestations include synovitis and dactylitis. Unlike radiographs that demonstrate late manifestations of the disease, ultrasound and MRI demonstrate early inflammatory changes of bones and soft tissues. Multiple sites of involvement may also be detected on a single examination. Both imaging modalities facilitate early diagnosis, a crucial element for patient management. Both modalities may also monitor lesion regression during treatment.

MRI of the hands in patients with rheumatoid arthritis is becoming routine. It is therefore necessary to develop simple standardized protocols providing fast imaging. It is best to image both hands simultaneously, from distal radioulnar to proximal interphalangeal joints, using a surface coil. Three imaging features are evaluated: synovitis, marrow edema and erosions. These can be quantified with the 'RAMRIS' score based on T1-weighted, fat-suppressed T2-weighted and fat-suppressed contrast material enhanced T1-weighted sequences in 2 planes (coronal and axial). Dynamic imaging provides improved evaluation of synovial inflammation.

To assess the accuracy and torerability of gadolinium-enhanced thoracic CTA using a 64 MDCT compared to a 16 MDCT. Because this study was started prior to the description of NSF, particular attention was paid to long-term follow-up of the patient population.The study protocol was approved by the ethics committee of our institution and informed consent was obtained from all patients. Fourteen patients (Group 1) (9 males and 5 females; mean age: 64.3 years) with contraindication to the administration of iodinated contrast material underwent thoracic CTA (collimation: 32 x 2 x 0.6 mm; pitch: 1.2) with gadolinium administration (0.5 mml/ml) at 0.4 mmol/kg injected at 6 ml/sec with evaluation of clinical and biological tolerability of the gadolinium based contrast agent. Results from this patient population were compared to results from a population of 31 patients (21 males; 10 females; mean age: 63.2 years) (Group 2) imaged on a 16 MDCT. All patients were folloowed-up for a mean time of 22.6 months.Using a mean contrast volume (standard deviation) that was not significantly different (Group 1: 54.8+/-11 ml; Group 2: 53.4+/-6.9 ml) (p=0.94), patients in Group 1 underwent complete thoracic CTA whereas patients in Group 2 underwent CTA of only the middle third of the thoracic region. All CTA examinations were diagnostic for Group 1 and Group 2 patients; however, evaluation of subsegmental vessels was possible in a significantly larger proportion of patients in Group 1 (10/14; 72%) compared to Group 2 (6/31; 19%) (p=0.003). Mean attenuation values within pulmonary arterial branches were similar for Groups 1 and 2 (central arteries: 194.5+/-51.3 HU vs 180.6+/-53.8 HU; p=0.38) (lobar arteries: 208.5+/-52.5 HU vs 189.9+/-60.1 HU; p=0.33) (segmental arteries: 220.4+/-50.4 HU vs 201.5+/-54.7 HU; p=0.42). Transient alteration of renal function was recorded in one patient from Group 1 with severe pre-existing chronic renal failure. No change in renal function was observed for Group 2 patients. No case of NSF was reported in patients with pre-existing renal failure at the time of enrollment.The use of gadolinium-based contrast agent for thoracic CTA using a 64 MDCT provides diagnostic quality examinations in all patients with improved image quality compared to a 16 MDCT. No complication other than transient alteration of renal function was observed. Because the likelihood of developing NSF may vary with the type of gadolinium-based contrast agent used, the least toxic agent should be used.

International audience; MR Urography (MRU) provides both morphologic and functional information without radiation exposure. It enables the assessment of split renal function, excretion, and quantification of obstruction. MRU is thus complementary to ultrasonography in the assessment of pre- and post-natal obstructive uropathies in children. If available, MRU should be definitely preferred to intravenous urography.

To determine whether quantitative dynamic contrast-enhanced MRI improves the performance of T2W-MRI for the localisation of non-palpable prostate cancer (PCa) and for the estimation of tumor volume.Twenty-three patients (PSA: 8.91+/-6.2ng/m) with a non-palpable cancer underwent endorectal MRI with T2W and dynamic contrast enhanced (DCE) imaging before radical prostatectomy. Each level of evaluation (apex, mid-portion, base) was divided in eight areas (24 areas per prostate and 552 areas for the 23 patients). Localisation and volume of tumor foci greater than 0,2cc present on the radical prostatectmoy specimens were retrospectively correlated to their MR appearance on the 552 evaluated areas. The dynamic parameters included capillary permeability (K(trans)), maximum concentration of gadolinium after 60s of perfusion ([Gd]) and wash-out (K(ep)). Uni- and multivariate analysis were performed to determine which parameters were predictive of PCa.Mean values of K(trans), K(ep) and [Gd] were significantly higher in the 58 tumor foci greater than 0,2 cm(3) of the PZ and the TZ (all p0.05). Logistic regression for each zone provides provided a value of the area under the ROC curve of 0.83 for the PZ and 0.81 for the TZ (0.7 and 0.75, respectively, for the T2W imaging), only significant for the PZ (p0.002). Sensitivity and specificity were 79 and 77% for the PZ, 62.5 and 94% for the TZ. Above 0,2 cm(3), tumor volume on dynamic MR showed a mean difference of 51+/-100% (range: -145 to +248%).Quantitative dynamic MRI is more accurate than T2W imaging for tumor localisation of non-palpable cancer greater than 0,2 cm(3), but the difference is only significant for the PZ. Above this volume, correlation between tumor volume measured on dynamic MRI and that on the specimen is poor.

Endometriosis is a frequent pathology of adult women. Clinical examination and US are poorly sensitive for detection of deep pelvic implants and MRI is superior for presurgical mapping of disease extent. This is important to optimize complete surgical excision, the only proven treatment to achieve symptomatic relief. The purpose of this pictorial essay is to describe the imaging features of deep pelvic endometriosis and the technical means to optimize its detection.

Nephrogenic systemic fibrosis, another problem for patients with chronic renal failure Nephrogenic systemic fibrosis is a rare but severe disease described in patients with kidney failure. High morbidity ant mortality are associated with this new condition. Epidemiological studies strongly suggest a link between nephrogenic systemic fibrosis and gadolinium administration for magnetic resonance imaging enhancement. The disease is primarily cutaneous, with oedema affecting the limbs, later evolving to fibrosis that leads to joints contractures. The lesions can spread to the trunk and involve systemic organs like the heart, lungs and muscles. Given the lack of proved efficient therapy, careful evaluation of the risks and benefits of gadolinium administration should be done in patients with kidney disease. If really needed, a highly stable contrast media should be used.

Nephrogenic fibrosing dermopathy is a cutaneous and systemic sclerosis affecting patients with renal failure.A 68-year-old man with renal insufficiency and on dialysis developed hardening of the skin and severe joint contractions. He had previously undergone angiography with gadolinium-containing contrast agents. A skin biopsy confirmed nephrogenic fibrosing dermopathy. The patient was treated by oral steroids followed by extracorporeal photopheresis. An improvement was seen after 12 cycles.Treatment of nephrogenic systemic fibrosis is not codified and is normally based on the methods used for other forms of systemic sclerosis. Six cases of patients showing improvement under extracorporeal photopheresis have been published. The physiopathology of the disease is unknown. Gadolinium could act as a triggering agent by attracting circulating fibrocytes in the dermis of patients. Medical authorities recommend avoidance of gadolinium in patients with advanced kidney failure unless strictly necessary.

Ewing's sarcoma is a relatively rare osseous malignant tumour. The age of onset is generally in the youth. Epidural localisation of the malignant osseous tumour Ewing's sarcoma is exceptional. Only 29 cases were reported in surgical literature including only one infected case.We report a case of a 24 years old patient who displayed a complete flaccid tétraplégia with T1 sensitive level. Spinal cord MRI documented a cervical posterior epidural process with peripheric gadolinium enhancement. Patient was operated in emergency. A C6 and C7 laminectomy allowed complete tumour resection with its purulent intratumoural collection revealed during the operation. A total tumour removal was performed. The immediate postsurgical evolution was remarkable, with a quasi complete recovery in the upper limbs.Firstly described by James Ewing in 1921, the spinal epidural locations of the Ewing's sarcoma are rare without specific clinical signs generally presenting as a radiculo-medullary compression. Our case is the second infected epidural Ewing sarcoma reported in the literature. However the cause remains unexplained. For this spinal epidural extraosseous tumour, X-ray radiography failed to show any osseous lesions. On MRI, the usually found aspect is a T1 and T2 isosignal with gadolinium enhancement.Through our observation, we underlined the scarcity of this pathology in the cervical epidural localization and the association with infection. We also emphasized on the complete removal, in order to give the best functional and vital outcome.

The aim of this work is to evaluate the relationship between improvement of regional myocardial function and visual analysis of contrast-enhanced (CE) MRI in patients after acute myocardial infarction. MRI was performed on 19 patients 1 and 11 weeks after a reperfused acute myocardial infarction. Perfusion data (first-pass images [FPI] and delayed CE images) were acquired after an intravenous bolus of gadolinium-DTPA and visually analyzed using a 17 segment model. Each segment was then classified in 3 groups, according to the presence or absence of FPI and CE patterns at baseline study: group 0: normal-appearing segments; group 1: segments with delayed hyper-enhancement but no early hypo-enhancement; group 2: segments with early hypoenhancement. Relative Wall thickening (RWT) was analyzed in each segment and its improvement evaluated in each group. Between first MRI and follow-up study, a significant improvement of RWT occurred in group 1 (mean +/- SD) [from 43.43 +/- 26.59% to 76.71 +/- 47.38%; p = 0.001] but not in group 2 (from 32.73 +/- 25.58% to 39.57 +/- 30.57%; p = NS). In group 0, RWT despite normal value at baseline study exhibited a significant improvement at follow-up (from 65.23 +/- 46.52% to 79.73 +/- 48.46%; p = 0.0015). In conclusion, the combined analysis of early and delayed perfusion abnormalities in MRI in the week following myocardial infarction can predict myocardial viability and allows in the future an evaluation of the efficacy of perfusion therapy.

Feasibility study of contrast enhanced MR enterography without enteroclysis as a new diagnostic tool for children with known or suspected Crohn's disease.We prospectively included 15 children, 8-18 years old, with clinical suspicion of Crohn's disease. MR enterography without enteroclysis was performed on a 1,5 T clinical MR system. A total of 1000 ml of mannitol 5% was orally administered 60 minutes prior to MRI. Coronal and axial breath-hold sequences were acquired. The following sequences were obtained: True-FISP, FLASH T1 2D/3D with Fat saturation before and after gadolinium injection. Two radiologists, blinded to patient information, independently reviewed all examinations to record image quality, the degree of distension of the distal ileum, the presence of abnormal bowel segments and the presence of extra-intestinal complications. MRI findings were correlated to sonographic, endoscopic and biological results (sensitivity, specificity, Kappa test).The examinations were considered of satisfactory diagnostic quality in 93.3% of patients. Respiratory artifacts were present in one case. The entire GI tract could be identified on all sequences. Distention of the distal ileum was recorded as good to excellent in 89% of healthy subjects. Five MR examinations were considered abnormal with isolated ileal involvement in 2 cases, ileocolic involvement in 2 cases, and isolated colonic involvement in 1 case. The sensitivity and specificity of MR for the positive diagnosis of Crohn's disease were 100% and 83% respectively. Three extra-intestinal complications were detected: one case of ileo-ileal fistula, not identified on ultrasonography, an asymptomatic anal fistula and a symptomatic inflammatory stricture.MR enterography without enteroclysis is a well tolerated, effective non invasive method in the evaluation of known or suspected Crohn's disease. Because of the absence of ionizing radiation, MR enterography should become the gold standard in pediatric patients.

To compare the assessment of infarct size using MRI and peak CK value.16 patients presenting with a first MI and seriall measurement of CK underwent gadolinium-enhanced MRI.A significant correlation was observed between both estimates of infarct size (r=0.56, p=0.0025). In addition, an inverse correlation was found between residual viability and peak CK (r=-0.51; p=0.043).After a first episode of MI, infarct size estimate by MRI correlates with that determined by peak CK measurement.

To determine the MR imaging features of immature hemangiomas. To discuss the value of MR imaging compared to Doppler ultrasonography (US).We performed a retrospective study of clinical, Doppler US and MRI data of 12 immature hemangiomas in 11 children. The mean age was 2 months and 21 days. The mean clinical follow up was 22 months and 7 days.MRI was performed for non-diagnosed lesions (4 cases) or to further define lesion extension (8 cases). The lesions either involved the head and neck (8 cases) or the extremities (4 cases). At MR imaging, all immature hemangiomas corresponded to well defined homogeneous T2W hyperintense masses. On T1-weighted images, 11 immature hemangiomas were isointense with intense homogeneous enhancement. Eleven tumors contained linear low signal intensity flow voids. Ten lesions had superficial cutaneous and/or subcutaneous extension whereas 2 lesions had intra-muscular extension. At Doppler US, immature hemangiomas were highly vascularized masses, with well defined margins, often compressibles, homogeneous isoechoic or heterogeneous with nodular hypoechoic foci, relative to subcutaneous fat. A diagnosis of immature hemangioma was confirmed either by pathology (2 cases) or clinical follow up (10 cases).In our study, the MR imaging features of immature hemangiomas were reproducible and similar to reports from the literature. MRI is a useful tool to better define the extent of immature hemangiomas, which can be difficult to assess at US. The sensitivity and specificity of MR imaging for this pathology remain to be defined.

We report the case of a 26-old-year man hospitalized for first partial complex epileptic seizure. Brain MRI showed an asymptomatic pseudo-tumor lesion in the brainstem. Diabetes insipidus, hypophyseal gonadotropic deficiency and osteosclerosis of long bones strongly suggested Erdheim-Chester disease, a rare histiocytosis, confirmed after tibial biopsy. Six months later, the patient remained stable. A persistent, and even increased, enhancement with Gd-DTPA on brain MR images was noted as previously described. The review of the literature collected 64 cases, and only 7 cases of cerebral "tumor".

A case of bulky abdomino-pelvic leiomyoma of the round ligament is reported with the CT (computed tomography) and MRI (magnetic resonance imaging) findings. Leiomyoma appeared as encapsulated heterogeneous tumor on the spontaneous contrast CT images and on post-gadolinium contrast MRI. Lack of specificity hinders diagnosis before surgery. Leiomyoma of the round ligament is the most frequent histological type among round ligament tumors. Leiomyoma of the round ligament must be retained as a possible etiology of inguinal mass or pelvic tumor.

Magnetic resonance imaging allows an accurate calculation of the left ventricular ejection fraction and left ventricular volumes. Additionally, it makes possible to assess myocardial perfusion after gadolinium chelate injection. Late after the injection, the presence of a myocardial hyper-enhancement can be visualized. The present study has used the 17 segment standardized nomenclature for tomographic imaging of the heart as recommended for all cardiac imaging modalities. Sixty nine patients were studied after a revascularised myocardial infarction. All patients had Timi grade 3 flow in the infarct-related artery after therapy. Regional and global function was studied using cine MR short axis slices. The gadolinium chelate first pass was scored using a 5 level scale reflecting the transmural extent of the segmental myocardial enhancement. The delayed enhancement due to gadolinium accumulation in the myocardium 10 min post injection was scored in the same manner. Left ventricular ejection fraction was 51 +/- 13%. Segmental thickening parameters (systolic thickness, absolute thickening and relative thickening) appeared statistically related to the hypoperfusion and delayed enhancement scores. Absolute myocardial thickening varied from 4.8 +/- 2.7 mm in the myocardial segments free of any delayed enhancement to 2.4 +/- 2.1 mm in segments presenting with a transmural extent of the delayed hyper-enhancement. Scores obtained after gadolinium injection were also well correlated with the global left ventricular function (r = 0.65, p0.01 for late enhancement). Magnetic resonance imaging of the heart allows a precise characterisation of revascularised myocardium which makes this technique very attractive for evaluating the treatments designed to improve myocardial microperfusion.

To report the experience of using various Gadolinium chelates as contrast media in digital subtraction angiography in patients with relative or absolute contraindications for iodinated contrast agents.and Methods. Forty-two arteriograms were performed in 39 consecutive patients using Gadolinium chelates (gadoteridol, gadodiamide, and gadopentetate dimeglumine). The vasculature of the brain, of the upper and lower limbs and the renal arteries were examined. Among these 39 patients, 17 were treated by various endovascular procedures.In 40 examinations out of 42, the angiographic result was satisfactory, allowing either a diagnostic evaluation or an endovascular therapeutic procedure. Clinical tolerance was excellent. In one case of renal failure that was reported after angiography, the patient had received both iodine and gadolinum-based contrast agents.Gadolinium appears to be an interesting alternative for arteriography in patients with absolute or relative contraindication to iodinated contrast agents, and also seems to demonstrate efficacy during endovascular therapeutic procedures.

Iodine-induced renal failure is a major concern when considering angiography in patients with renal insufficiency. Previous studies have shown that gadolinium can perform well as a radiographic contrast agent and is not nephrotoxic at dosesor = 0.4 mmol/kg. We report high-quality images of the inferior vena cava, obtained by digital subtracted venography using power-injected gadodiamide through the common femoral vein. This technique, in combination with ultrasound, appears as a good alternative for insertion of vena cava filters in patients with renal failure or those with prior episodes of contrast induced renal failure or allergy.

We report a case of an immunocompetent man who developed primary spinal intramedullary malignant lymphoma. This condition occurs in about 0.9 p. 100 of primary central nervous system non-Hodgkin lymphomas in non-AIDS patients. Magnetic resonance imaging was nonspecific but suggestive. Like the brain localization, prognosis is poor. Because of the high frequency of recurrence, usually confined to the central nervous system with neuraxis dissemination, treatment must be delivered to the entire neuraxis. But more effective treatment strategies with radiotherapy-chemotherapy combinations will be needed. Feasibility and toxicity patterns remain to be determined.

Placenta accreta results from an abnormal attachment of the placenta to the uterine myometrium. The reported incidence in literature is variable, with an average of 1/7000 pregnancies. This condition is associated with a significant risk of bleeding at the time of delivery, usually requiring hysterectomy. Sonography associated with color Doppler is useful for diagnosis, but MRI can be used successfully to evaluate the degree of placental tissue invading into the myometrium, the serosa, and for follow-up after conservative management. To our knowledge, only two cases of placenta accreta evaluated with MR and six cases of placenta accreta treated by embolization have been reported in the literature. The authors report one case of placenta accreta treated successfully by embolization, and followed-up by MRI.

Epidermoid cysts are rare intradural extramedullary tumors. There are two types of lesions: congenital spinal cysts frequently associated with other bone or skin malformations (spina bifida aperta, dermal sinus ...) and iatrogenic spinal cysts resulting from lumbar puncture. In both situations, clinical and the radiologic findings are similar. We describe an epidermoid cyst in a 52-year-old female affected with a lumbar pain and recent urinary disorders. Symptoms were slow to appear and dependent on the location of the cyst. Epidermoid cyst contained keratin, cholesterol crystals and desquamed epithelial cells. On CT, epidermoid cyst was a hypodense lesion on MR. On T1 weighted images the tumor was hypointense. The signal appeared heterogeneous. There was no enhancement after Gadolinium DTPA injection. Differential diagnosis included: ependymoma, hemangioblastoma, neurinoma, meningioma and metastasis, but all these lesions are enhanced by contrast injection.

The development of new non-ionic magnetic resonance (MR) contrast media as gadodiamide injection increased the choice of paramagnetic contrast agents available in MR of the central nervous system (CNS). The purpose of our paper was to compare at the dose of 0.1 mmol/kg b.w. the safety of gadodiamide (Gd-DTPA-BMA) to gadopentetate dimeglumine (Gd-DTPA) and to gadoterate meglumine (Gd-DOTA) in two multicentric double-blind studies. A total of 551 patients were enrolled with 143 patients in the Gd-DTPA group, 132 patients in the Gd-DOTA group and 276 patients in the Gd-DTPA-BMA group. Safety was assessed by recording the adverse events up to 24 hours after the injection. One or more adverse events were recorded in 14% of the Gd-DTPA patients, in 15.1% of the Gd-DOTA patients and in 11.6% of the Gd-DTPA-BMA patients. These reactions were related to the contrast media in 9.1%, 13.6% and 8.7% of the cases respectively. Their intensity was defined as mild in 8.4% of the patients in the Gd-DTPA group, in 13.6% of the patients in the Gd-DOTA group and in 8.3% of the patients in the Gd-DTPA-BMA group. No severe reaction or death were recorded. An injection-site reaction (heat, coldness, pain) has been observed in 43% of the cases although an adverse event other than local reactions (headache, dizziness, nausea) has been noticed in 57% of the cases. No significant statistical difference was observed between the groups. Gadodiamide is a safe and effective contrast agent in MRI of the CNS in comparison with Gd-DTPA and Gd-DOTA currently in routine use.

Gadodiamide injection (Gd-DTPA-BMA) is a new non-ionic paramagnetic contrast agent for which the safety at the dose 0.1 mmol/kg was evaluated during a European multicentre study on a large population of adult patients who had an MR examination of the central nervous system with contrast medium. The safety analysis was performed on 2,102 patients by recording the adverse events observed during injection and up to 24 hours after the injection. Adverse events due or probably due to gadodiamide injection were observed in 102 patients (4.4%) with injection-site associated discomfort (heat, coldness, pain at the injection site) in 37 patients (1.8%) and adverse events other than discomfort (headache, nausea, vomiting) in 35 patients (3.1%). No adverse events of severe intensity or death were reported during the trial. Gadodiamide injection was shown to be safe and well tolerated and represents a non-ionic alternative to the current products in the field of MR imaging of the central nervous system.

We report one case of histologically proved Lhermitte-Duclos disease. Suspected on the basis of CT and angiography, the pre-operative diagnosis has been confirmed by the characteristic features of the lesion on MRI: a unilateral posterior fossa mass, hyperintense on proton density and T2-weighted images, hypointense on T1-weighted images, non enhancing after Gd administration. The gyral pattern was preserved, but a specific thickening of cerebellar folia was demonstrated. Despite a good post-operative short term prognosis, recurrence may occur. With a better depiction of lesion limits, MRI could improve the surgical approach and reduce the risk of subtotal excision.

A patient with subacute transverse myelitis (TM) had MRI studies, including scans after Gd-DTPA administration. The enhancement, with its intensity and persistence, seems to herald residual cord deficits. TM remains a clinical diagnosis of exclusion whereas MRI plays a valuable role in the assessment of the different abnormalities which may produce this syndrome and also defines accurately the location and extent of the intramedullary pathology.

Thirty intracranial tumours were explored by MRI, using T1- and T2-weighted sequences, before and after intravenous injection of Gd-DTPA. Two-thirds of the intra-axial tumours were accurately detected on one section plane by MRI without Gd-DTPA, but in one quarter of the cases Gd-DTPA only delineated precisely the tumour. On the other hand, Gd-DTPA failed to detect certain tumours (benign gliomas) or showed only a small part of them (mixed grade gliomas), while they were detected by MRI without contrast injection. However, in such cases Gd-DTPA was useful for the stereotaxic biopsy of the tumour. Gd-DTPA appears of lesser interest in extra-axial tumours. Gd-DTPA is thus valuable for the neuroradiological diagnosis of brain tumours, particularly to evaluate the grade of gliomas and to confirm the diagnosis of recurrent growths.