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Introduction: Executive function impairments and high level of impulsivity may constitute heritable endophenotypes that confer predisposition for alcohol dependence. Brain volume abnormalities have also been reported in young, alcohol-naïve subjects at high risk (HR) for alcohol dependence, and linked to cognitive dysfunction., Methods: This paper presents a literature review of magnetic resonance imaging (MRI) studies that examined brain volumes in adolescent/young adult HR offspring from families with multiple cases of alcohol dependence compared to low risk controls with no family history of alcohol or drug misuse. In some of these studies, executive functioning and externalizing symptoms were also assessed., Results: In HR subjects, local white matter volume deficits were found in the corpus callosum and in the right orbito-frontal cortex, and lower fractional anisotropy in the left inferior longitudinal fasciculus and in the right optic radiation. Altered fronto-cerebellar connectivity has also been reported. Diminished gray matter volume of the cerebellar cortex was found in HR subjects, in the frontal, cyngulate and para-hippocampal gyri, and also in the amygdala, the thalamus and the cerebellum. These structural abnormalities have been associated with higher impulsivity level and executive function impairments, themselves markers of vulnerability to alcoholism. These premorbid cerebral abnormalities may increase the risk for developing an alcohol use disorder in HR subjects through atypical control processing., Conclusion: Brain abnormalities may potentially constitute an abnormal neural network that might underlie the risk towards alcohol dependence. These circuitry abnormalities might contribute to the reward deficiency, as well as impaired response inhibition that predict impulsive spectrum behavior, which are thought to represent the inherited vulnerability to alcohol dependence in HR individuals., (Copyright © 2013 L’Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.)

Glomerular Filtration Rate (GFR) is one of the cardinal indices of renal function and is used clinically as the gold standard of renal dysfunction. In the past decade, many studies using dynamic contrast-enhanced MRI (DCE MRI) to measure GFR have been published. The MRI evaluation of GFR centers on visualizing the passage of contrast material (Gadolinium chelates) through the kidney. MRI appears as a promising tool but still relatively difficult to implement in the assessment of GFR. A high heterogeneity of protocols (e.g., in acquisition mode, dose of contrast, postprocessing techniques) is noted in the literature, reflecting the number of technical challenges that should first be solved in order to reach a consensus, and the reported accuracy and reproducibility are insufficient for justifying their use in clinical practice now. This paper presents and discusses the different steps that can be used to quantify the GFR by MRI., (Copyright © 2011 Elsevier Masson SAS and Éditions françaises de radiologie. All rights reserved.)

The MR Breast Imaging Reporting and Data System (BI-RADS) lexicon of the American College of Radiology (ACR) includes a new lesion category defined as non-masslike enhancement. The purpose of this paper is to review the definition of this new entity, illustrate the main imaging features described in the BI-RADS lexicon and to propose a diagnostic approach based on data from the literature in order to achieve diagnosis and optimal patient management.

Prognosis for endometrial carcinoma is closely related to cell type and tumor grade but also to local staging using the FIGO classification. MRI, under specific technical conditions, allows excellent depiction of the degree of myometrial tumor extension. It also has an excellent specificity for the detection of cervical extension. In addition, it allows evaluation of regional nodes, but with sensitivity values that are not perfect. The purpose of this paper is to review the MR imaging features of endometrial carcinoma along with its limitations and pitfalls.

Unlabelled: Deep pelvic endometriosis is an invalidating disorder affecting the retrocervical region, rectosigmoid colon and urinary bladder generally requiring surgical management. MRI is the preoperative imaging modality of choice. The purpose of this paper is to describe the MR imaging features of deep pelvic endometriosis with laparoscopic correlation., Methods: Thirty-five patients with clinical suspicion of deep pelvic endometriosis underwent pelvic MRI. Results of MRI, including morphological and signal characteristics features of the lesions were compared to laparoscopic fidings., Results: Laparoscopy detected lesions of deep pelvic endometriosis of the uterosacral ligaments (n=10), torus uterinum (n=9), rectosigmoid (n=11), Douglas pouch (n=9), recto-vaginal septum (n=6), bladder (n=4) and posterior vaginal cul-de-sac (n=2). The sensitivity, specificity, positive predictive value and negative predictive value of MRI were assessed for each localization., Conclusion: MRI allows diagnosis of deep pelvic endometriosis of the bladder, rectosigmoid and Douglas pouch and with lower sensitivity for lesions of the uterosacral ligaments, posterior vaginal cul-de-sac and rectovaginal septum.

The role of MRI for presurgical local staging of breast cancers amenable to conservative treatment has been the subject of multiple publications and tends to become a "validated" indication in routine practice. The purpose of the paper is to review the advantages and limitations of this imaging modality that is part of a comprehensive management that must be validated by clinical data especially with regards to local recurrence and survival. Knowledge of these elements combined with more precise indications should result in improved patient management while avoiding overtreatment or unnecessary anxiety-producing examinations.

This paper describes MRI aspects of a leukodystrophy due to the Mitochondrial Neurogastrointestinal Encephalomyopathy syndrome in an adolescent girl investigated for nocturnal recurrent emesis leading to major cachexia.

CNS tuberculosis remains relatively frequent in endemic regions. Both CT and MRI are valuable for diagnosis. Even though non-specific, MRI including diffusion-weighted imaging and proton spectroscopy is more sensitive than CT for detection of some lesions. The purpose of this paper is to illustrate the imaging features of CNS tuberculosis.

In this paper, the imaging features of traumatic injuries of the spine in an emergency department will be reviewed. Three themes are discussed. 1) Review of current indications for additional imaging work-up. Conventional radiographs are not always mandatory, especially at the cervical level since validated criteria are available from the literature. The low sensitivity of conventional radiographs often requires additional imaging by CT (bone lesions) or MRI (disk and ligamentous lesions). The degree of urgency in scheduling these different examinations will be defined by the clinical setting and risk level (low/intermediate/high) of the injury. 2) Review of imaging features associated with stable and unstable lesions. The analysis of conventional radiographs is based on biomechanical concepts. The features of the main lesions will be illustrated by clinical cases and diagrams. 3) Review of key points that must urgently be transmitted to clinicians. The preliminary radiology report is an essential document for the management of patients with traumatic injury to the spine. It will have an impact on the type of immediate management (medical, orthopedic or surgical). A final report validating the initial interpretation should, of course, soon follow.

Chronic otitis media (COM) can be divided into two subtypes: COM with cholesteatoma (including precholesteatomatous states) is an aggressive form of otitis. Surgical treatment is mandatory because of the risk for labyrinthine or cerebromeningeal complications. CT is very important in the preoperative work-up (extension of cholesteatoma, anatomic variants). In patients who have undergone middle ear surgery, CT and presently MRI play an increasing role in the detection of recurrent or relapsing cholesteatoma. COM without cholesteatoma does not have an osteolytic potential, but may leave auditive sequelae that in selected cases may warrant surgical treatment to improve hearing. CT is useful in the etiological work-up of patients with severe hypoacusis. CT also plays an important role in cases of surgical failure, to detect a dislocation of the ossiculoplasty or impairment of the middle ear caused by fluid effusion. The objective of this paper is to specify the indications, the results and the limits of pre- and postoperative imaging in COM.

The number of structural neuroimaging studies of bipolar disorder have increased during recent years, expanding the literature on the nature of cerebral abnormalities underlying this disorder. The purpose of this paper is to provide a selective review on the main issues concerning this literature. Consistent findings are higher rate of periventricular and deep subcortical white matter hyperintensites seen on MRI. Although there is strong evidence for links between hyper-intense lesions and age or cardio-vascular risk factors, some authors have observed the presence of these abnormalities early in the course of the illness. There are also frequent reports on ventricular enlargement, which has been described as mild and predominant in the right lateral ventricle. Total cerebral volume appears to be preserved. Whereas changes in total grey matter volume are uncertain, evidence suggests that reduced white matter volume reflects genetic factors predisposing to the disorder. Recent studies have reported volume changes in several cortical areas including the subgenual cingular, frontal and temporal cortices. Additionally, a number of reports described morphometric abnormalities in various subcortical structures, such as amygdala, basal ganglia and thalamus. Part of the variability in the morphometric abnormalities might be attributable to differences in clinical status and demographic characteristics of patient groups. Despite some inconsistencies across the studies, it emerges that abnormalities are asymmetrically distributed throughout the two cerebral hemispheres. When increase in volume is reported, it is preferentially localised in the left cerebral hemi-sphere and more specifically in prefrontal and temporal cortices and in amygdala. By contrast, when structural abnormalities concern the right cerebral hemisphere, they are identified as deficits. These latter results are in direct line with those of studies of mania following brain injuries, which report that these secondary mania result mainly from right cerebral lesions. It is also important to notice that most of the abnormalities concern both the cortical and subcortical level, ie frontal, striatal, thalamic and limbic regions. These abnormalities highlight the role in the pathophysiology of bipolar disorder of the loops involved in emotional information processing. The particular role of fronto-limbic loops in the phenomenology of bipolar disorder have been emphasised by recent data from functional neuroimaging studies.

Over the last years, technical advances in neuroimaging have allowed drastic improvements in the assessment of acute ischemic cerebral events. Beyond conventional morphological analysis, diffusion-weighted and perfusion-weighted MRI now enable routine functional assessment of brain tissue; spectroscopy and diffusion tensor imaging still remains in the domain of clinical research. During acute ischemia events, diffusion-weighted MRI can detect the movements of water molecules and cytotoxic edema related to cell injury enabling rapid diagnosis and early assessment of cerebral ischemia. In conjunction with perfusion imaging, which detects hypoperfusion areas, diffusion-weighted MRI provides a means to identify areas of penumbra ischemia. More recent multislice computed tomographic (CT) scans with multimodal analysis are also very competitive for assessment of cerebral ischemia (non-enhanced CT, CT angiography and perfusion CT). The purpose of this paper is to describe the CT and MRI patterns during the different stages of cerebral infarcts.

The purpose of this paper is to report the clinical, imaging (sonographic, mammographic and MRI) and pathological features of breast angiosarcoma, a rare but aggressive tumor, based on a review of two cases.

Primary retroperitoneal tumors are rare and most of the time malignant. Because of the large space in which they grow, they are often discovered lately as they are large. CT and MR are the imaging techniques of choice for the primary diagnosis and the follow up of these tumors. Multiplanar reconstructions , signal and density resolution help for the nature diagnosis. The examinations allowed to find associated signs that helps also for the right diagnosis. The purpose of this paper is to answer a serie of questions: Is the mass in the retroperitoneal space? Are they imaging signs that helps for the diagnosis of nature? Are they associated signs that helps for the diagnosis of nature? What are the most common diagnosis? Is there any place for percutaneous biopsies? What is the role of imaging in the follow up? Are there any other processes that can mimic retroperitoneal tumors?

Ventriculomegaly constitutes the major indication of fetal brain MRI. MRI is therefore of utmost importance to look for a cause through the depiction of criteria of malformations and through the definition of criteria of destructive lesions. Malformations and destructive lesions are the most common causes of ventricular dilatation. Some challenging points are worth mentioning in term of mechanism with the challenge of hydrocephalus (in term of increased in intracranial pressure) and of isolated ventriculomegaly. The image itself is also challenging since a similar image may be of different origin. In term of natural history of fetal brain injury an irregular, nodular aspect of the ventricular wall and/or the germinal matrix is often the only pathologic MRI finding that is known to be of clastic origin. In term of prognosis the challenge is represented by the isolated mild ventriculomegaly, the literature being quite confusing. The purpose of this review paper is to highlight the underlying mechanisms and pathophysiology of ventricular dilatation based on results from the literature as well as from personal experience.

Neonatal brain disorders consist of a wide chapter including brain malformations, hypoxic-ischemic encephalopathy, intracranial infections, perinatal trauma and metabolic encephalopathies. The aim of this review paper is to describe the main imaging modalities (ultrasonography, CT, MRI) that are used extensively for the diagnosis of neonatal brain disorders, with their respective advantages and limitations, to illustrate and describe the main brain lesions encountered in the neonatal period, particularly with MRI since its role has increased over the recent years. We will focus on hypoxic-ischemic encephalopathy, materno-fetal infections, metabolic encephalopathies and stroke, those four conditions being the most frequent so far. Imaging modalities, especially MRI, by showing the extent of brain damage, are part of the prognostic factors in cases of infective causes and of hypoxic-ischemic origin. MRI is also very efficient in showing brain damage as atrophy and white matter abnormalities suggestive of an underlying abnormal brain of metabolic origin.

Indications for sialography have became rare and radiologists are less and less experienced for salivary gland cannulation. MR Sialography allows opacification of salivary ducts without any cannulation and could replace residual indications for sialography. The purpose of this paper is to review the principle of the technique, the normal and pathologic aspects of MR Sialography and to emphasize advantages and limitations compared to other techniques.

This paper will review the diagnostic imaging work-up of disc-related nerve root impingement including the role and technique of CT and MRI. Clinical and anatomical elements will be reviewed along with considerations regarding the radiology report, including a review of the proper descriptive terminology. Finally, clinical and imaging pitfalls will be discussed. In addition to specific features related to thoracic and lumbar segments, clinical and imaging differential diagnoses are reviewed: non-disc related radicular pain (intradural or extra-spinal), differential diagnosis of "enlarged" nerve roots (free disc fragment, cyst of a nerve root sleeve, tumors, normal variants.).

Since the description of cortical deafness, it has been known that the superior temporal cortex is bilaterally involved in the initial stages of language auditory perception but the precise anatomical limits and the function of this area remain debated. Here we reviewed more than 40 recent papers of positron emission tomography and functional magnetic resonance imaging related to language auditory perception, and we performed a meta-analysis of the localization of the peaks of activation in the Talairach's space. We found 8 studies reporting word versus non-word listening contrasts with 54 activation peaks in the temporal lobes. These peaks clustered in a bilateral and well-limited area of the temporal superior cortex, which is here operationally defined as the speech sensitive auditory cortex. This area is more than 4cm long, located in the superior temporal gyrus and the superior temporal sulcus, both anterior and posterior to Heschl's gyrus. It do not include the primary auditory cortex nor the ascending part of the planum temporale. The speech sensitive auditory cortex is not activated by pure tones, environmental sounds, or attention directed toward elementary components of a sound such as intensity, pitch, or duration, and thus has some specificity for speech signals. The specificity is not perfect, since we found a number of non-speech auditory stimuli activating the speech sensitive auditory cortex. Yet the latter studies always involve auditory perception mechanisms which are also relevant to speech perception either at the level of primitive auditory scene analysis processes, or at the level of specific schema-based recognition processes. The dorsal part of the speech sensitive auditory cortex may be involved in primitive scene analysis processes, whereas distributed activation of this area may contribute to the emergence of a broad class of "voice" schemas and of more specific "speech schemas/phonetic modules" related to different languages. In addition, this area is activated by language-related lip movement, suggesting that a multimodal integration of the auditory and the visual information relevant in speech perception occurs at this level. Finally, there is a task-related top-down modulation of the pattern of activation of the speech sensitive auditory cortex which may reflect the fact that the different parts of this structure are connected to different down-stream cortical regions involved in the neural processing of different types of tasks.

The bone marrow is a complex organ that contains fat and nonfat cells, the proportion of which varies greatly with age and in the different bones of the skeleton. Magnetic resonance imaging provides information on the composition of the medullary cavity of any given bone and on the distribution of red and yellow marrow in the skeleton. The wide spectrum of appearances of the normal bone marrow at MR imaging will be reviewed. The purpose of this paper is to determine the MR appearance of the bone marrow, to illustrate the phenomenon of marrow conversion and to familiarize the readers with the complex parameters that interfere with the MR appearance of normal bone marrow.

In spite of its many advantages: 3D imaging, improved tissue characterization, and lack of ionizing radiation, interventional MRI remains seldom used. Several factors are involved. The purpose of this paper is to analyze the factors preventing or slowing the development of this technique based on a review of data from the literature, work presented at the second symposium on interventional MRI (Düsseldorf, 1997), and our own experimental data. The following elements will be discussed: difficulties related to image quality and open magnets, control of targeted image acquisitions, MR environment and problems related to asepsis, as well as advances of other techniques. Finally, short-term and mid-term perspectives will be presented. These are related to the goals of the technique: open or short bore closed magnets? MR unit installed in a radiology department? MR unit dedicated to interventional procedures only or mixed diagnostic-interventional unit? interventional MR unit placed in a neurosurgery operating room? interventional MR unit installed in a general surgery operating room?

A good knowledge of the brain anatomy is necessary for all physicists interested in neurologic pathology, and especially for the radiologists. The aim of this paper is to summarize the important data in morphological but also in functional brain anatomy. The main neurologic pathways are represented on MR standard slices for practical application. The international anatomica nomenclatura (french terms) is used.

The purpose of this paper is to present a pictorial display of osseous and articular lesions of the anterior chest wall. The role of CT and MR imaging in such disorders is emphasized. Imaging of the anterior thoracic wall by plain films is particularly difficult. However numerous disorders may be encountered. They include inflammatory hyperostosis and sclerosis of the clavicle and the sternum, condensing osteitis and post-traumatic osteolysis of the clavicle, radiation osteitis of the sternum and the ribs, septic arthritis of the sternoclavicular joint, primary and secondary tumors of the sternum and the ribs. We illustrate a spectrum of such lesions in which CT and MR imaging provides acute evaluation of both soft tissue and bone details.

We describe in this paper how the STEAM sequence can be an efficient tool to obtain images free of flow artifacts in anatomical situation where the spin echo failed. The simplest way to eliminate flow artifacts is to exploit the dephasing induced by motion in magnetic field gradients and to reduce to zero the signal from moving tissues. This can be achieve by increasing the time elapsed between the spin excitation and the signal observed. Because of T2 relaxation, such an increase results in a signal decrease when the spin echo sequence is used. The STEAM sequence has the unique property that the time elapsed between observation and excitation can be increased without change in T2 value and so allows a good suppression of signals from the moving spins with short TE. Our results demonstrate that, although the stimulated echo intensity is only half that of a spin echo taken at the same read out time, the advantages of STEAM imaging can compensate for this partial loss in signal to noise in some particular clinical situations. The influence of mixing time on contrast has been evaluated using thoracic spine imaging and it has been shown that contrast between spine and CSF can be significantly improved (+ 60%) when TM is increased (from 17 ms to 50 ms). In the same time, the contrast between spine and fat issue decreases (40%). This last effect facilitates the adjustment of contrast window. Suppression of motion artifacts has first been evaluated with thoracic spine imaging, using a whole body coil. Suppression of artifacts was better than that obtained with a flow compensated spin echo sequence, especially in the case of kyphotic patients when a presaturation band was inefficient. In a second step suppression of motion artifacts has been evaluated from posterior fossa examination after injection of a paramagnetic contrast agent. The images obtained with the stimulated echo sequence show a dramatic reduction of signal from blood in the lateral sinus, and therefore an increase of quality by elimination of motion artifacts.

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.

MRI is the standard exploration of intramedullary tumours. Following up the patients is of prime importance to detect and treat possible recurrences at an early stage. The purpose of this paper is to specify the postoperative MRI semiology of intraspinal gliomas. During the 1986-1992 period, 47 patients operated upon in the Bicêtre hospital for primary intraspinal tumours were followed up with high-field MR (1.5 Tesla, Signa, G.E.). The retrospective visual study was carried out by two neuro-radiologists. The patients' group consisted of 24 women and 23 men aged from 15 to 67 years (mean 38 years). The tumours treated were 29 ependymomas and 18 astrocytomas. Eighty-five MRI examinations were analysed. Most of them comprised at least two planes in T1 and T2-weighted spin echo sequences with gadolinium injection, then only T1-weighted spin echo sequences after gadolinium injection (0.1 mmol/kg). The mean postoperative follow up period in the 47 patients was 32 months (range 7 to 84 months). Contrast enhancement of the spinal cord was observed in 20 cases. In the 6 patients with recurrence (5 astrocytomas, 1 malignant ependymoma) there was a segmental increase of spinal cord volume with contrast enhancement after gadolinium injection. In 3 out of these 6 patients clinical deterioration appeared later than MRI semiology. In clinically stable patients neither enhancement nor increase in spinal cord size was found in 27 cases, and enhancement alone was noted in 12 cases. There was no reliable criterion in the analysis of post gadolinium signal enhancement that could be used to differentiate recurrence from cicatricial contrast enhancement.(ABSTRACT TRUNCATED AT 250 WORDS)

The non neoplastic diseases of the nasopharynx are uncommon especially in adults. Cyst of pharyngeal bursa or Thornwald cyst are located in the supero-posterior nasopharynx, in the location of the normal pharyngeal bursa which open into the pharyngeal mucosa. When it persists, a cyst can develop if the orifice becomes occluded. The have a characteristic and distinctive C.T. and N.M.R. aspects, as presented in this paper, well circumscribed round midline mass, sparing muscles lateral as well as posterior, with an high signal in T1 and T2 N.M.R. sequences. No discussion with other pathologic conditions is useful because carcinoma, adenoid and pharyngeal polyp, or Killian's polyps haven't this configuration.