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At least 1,387 records · Page 77Linked to original sources
PubMed2000

Visualization of fibrous cap thickness and rupture in human atherosclerotic carotid plaque in vivo with high-resolution magnetic resonance imaging.

BACKGROUND: The results of studies of advanced lesions of atherosclerosis suggest that the thickness of the fibrous cap that overlies the necrotic core distinguishes the stable lesion from one that is at high risk for rupture and thromboembolic events. We have developed a high-resolution MRI technique that can identify the fine structure of the lesion, including the fibrous cap, in vivo. The aim of the present study was to determine the agreement between in vivo MRI and lesion architecture as seen on histology and gross tissue examination to identify fibrous cap thickness and rupture. METHODS AND RESULTS: Twenty-two subjects who were scheduled for carotid endarterectomy underwent MRI with a 3-dimensional multiple overlapping thin slab angiography protocol. The appearance of the fibrous cap was categorized as (1) an intact, thick, (2) an intact, thin, or (3) a ruptured fibrous cap on MRI, gross, and histological sections. Thirty-six sites were available for comparison between MRI and histology. There was a high level of agreement between MRI and histological findings: 89% agreement, kappa (95% CI)=0.83 (0.67 to 1. 0), weighted kappa=0.87. Spearman's correlation coefficient was 0.88 (significant to the 0.01 level). CONCLUSIONS: These findings indicate that high-resolution MRI with a 3-dimensional multiple overlapping thin slab angiography protocol is capable of distinguishing intact, thick fibrous caps from intact thin and disrupted caps in atherosclerotic human carotid arteries in vivo. This noninvasive technique has the potential to permit studies that examine the relationship between fibrous cap changes and clinical outcome and to permit trials that evaluate therapy intended to "stabilize" the fibrous cap.

Carotid Arteries↗
PubMed2003

[Comparison of three-dimensional gradient echo, turbo spin echo and steady-state gradient echo sequences in axial MRI examination of the cervical spine].

PURPOSE: The aim of this study was to assess the detectability of the structures that are affected by cervical spondylosis by different 3D MRI sequences and compare the image quality of those sequences. MATERIALS AND METHODS: Twenty healthy volunteers were examined using a 1.5 T MR unit. T2* weighted 3D-gradient echo sequence with magnetization transfer saturation pulse (3D-FFE-MTC), T2 weighted 3D turbo spin echo (TSE) sequence with and without spectral presaturation inversion recovery pulse (T2-3D-TSE/SPIR+ and T2-3D-TSE/SPIR-) and balanced-FFE (b-FFE) sequences were compared. Spinal cord signal-to-noise ratio (SNR), cerebrospinal fluid (CSF) SNR, and CSF-spinal cord contrast-to-noise ratio (CNR) were calculated quantitatively. The detectability of neural foramina, spinal nerve roots, uncinate process and ligamentum flava were graded on a 5-point scale (0: minimum, 4: maximum) qualitatively. The presence of the artifacts and overall image quality were graded on a 4-point scale (0: minimum, 3: maximum). RESULTS: Balanced-FFE sequence yielded the best results for each of three quantitative evaluation. In terms of qualitative evaluation, for the uncinate process T2-3D-TSE/SPIR- sequence was superior to the other three sequences (p < 0.01). For the ligamentum flava T2-3D-TSE/SPIR- and b-FFE sequences were superior to the other two (p < 0.01). For the neural foramina b-FFE yielded the lowest score (3), however the other three sequences were not significantly different (3.2-3.5) (p > 0.05). Artifacts were most commonly seen using 3D-FFE-MTC. In terms of overall image quality T2-3D-TSE/SPIR- yielded the highest score, followed by b-FFE. CONCLUSION: 3D-FFE-MTC sequence is frequently preferred for cervical spinal MRI studies. However our study yielded best scores for T2-3D-TSE/SPIR, followed by b-FFE in the quantitative and qualitative evaluation of the structures affected by cervical spondylosis.

Adolescent↗
PubMed2005

Magnetic resonance imaging evidence for widespread orbital dysinnervation in congenital fibrosis of extraocular muscles due to mutations in KIF21A.

PURPOSE: High-resolution orbital magnetic resonance imaging (MRI) was used to investigate the structural basis of ocular motility abnormalities in humans with congenital fibrosis of the extraocular muscles type 1 (CFEOM1) due to missense mutations in the developmental kinesin KIF21A. METHODS: Clinical ophthalmic and motility findings in 19 volunteers from six unrelated CFEOM1 pedigrees harboring four of the six reported KIF21A mutations and 23 normal control subjects were correlated with MRI studies demonstrating extraocular muscle (EOM) size, location, contractility, and innervation. RESULTS: Subjects with CFEOM1 had severe bilateral blepharoptosis, limited supraduction, and variable ophthalmoplegia. In affected subjects, MRI demonstrated atrophy of the levator palpebrae superioris and superior rectus EOMs and small or absent orbital motor nerves. The oculomotor nerve was most severely hypoplastic, but the abducens was also affected. EOMs exhibited variable atrophy and an abnormally bright T1 signal. Subjects with the R954W and R954Q substitutions frequently exhibited A-pattern strabismus, with misinnervation of the lateral rectus muscle by an oculomotor nerve branch. Rectus pulley locations were generally normal. Subjects with CFEOM1 exhibited subclinical but highly significant reduction from normal in mean optic nerve size (P < 0.001). Comparing clinical and MRI phenotypes did not reveal distinguishing features among KIF21A mutations. CONCLUSIONS: Orbital imaging in CFEOM1 due to various amino acid substitutions in the kinesin KIF21A demonstrates consistent abnormalities of motor and sensory innervation in the orbit. These findings suggest that neuronal disease is primary in CFEOM1, with myopathy arising secondary to abnormal innervation and minimal rectus pulley abnormality secondary to reduced EOM forces.

Adolescent↗
PubMed1989

[Clinical application of magnetic resonance imaging in gynecology].

Thirty-five women were examined with female pelvic magnetic resonance imaging (MRI). 5 cases demonstrated normal pelvis structures, 3 had physiological atrophic changes, and one had an underdeveloped uterus. The other 26 cases consisted of 8 leiomyoma of uterus, 11 ovarian benign tumor, 3 ovarian cancer, 2 cervical and 2 endometrial carcinoma. Images of normal uterus as well as those pathological conditions mentioned above were depicted, and compared with the operative findings. By means of MRI, we were able to demonstrate the origin of most of the pelvic masses, number, size and location of leiomyoma, myometrial penetration, parametrial extension and lymph node metastasis of endometrial carcinoma. Cervical malignancy could be accurately staged, and serous cyst was possibly distinguished from hemorrhagic cyst. However, one case of mucinous cystadenoma was misdiagnosed as dermoid cyst; one myoma, 1 cm in diameter, in same density as the uterine muscle was overlooked and one mesonephroma of 0.3 cm in diameter situated deep in the cervical fibrous tissue was not detected.

Adolescent↗
PubMedDate not supplied

[Assessment with magnetic resonance of reconstruction of the posterior cruciate ligament. Preliminary experience].

Posterior cruciate ligament (PCL) tears are definitely less common than anterior cruciate ligament (ACL) tears: their incidence in literature ranges 3-20% of all capsuloligamentous injuries versus 45-90% for ACL tears. Recent papers reported that if these injuries are not operated on, they evolve first into medial femorotibial and femoropatellar arthrosis and then into tricompartmental arthrosis. There are several MR studies dealing with ACL reconstruction, while MR studies on PCL reconstruction are lacking, both because the frequency of the latter injuries is lower and because they are difficult to demonstrate. We report our preliminary experience with PCL reconstruction studied with MRI in 12 patients submitted to arthroscopy. We used the ipsilateral patellar tendon (11 cases) or the contralateral one (1 case). The patients were submitted to MRI 4-16 months after surgery. Axial, coronal and sagittal images were acquired, together with oblique sagittal and coronal slices to show the graft completely. We also used SE, GE and fat suppression STIR MR sequences, trying to identify which of them are the most useful in patients with healing or exudative reaction in the intercondylar notch. MR exams were performed with a dedicated permanent magnet (0.2 T) and a permanent total body unit (0.3 T). The graft was clearly depicted on all images in 11 patients, while graft retear was shown in 1 patient. MRI did depict the whole graft in all patients, which finding is useful to study the signal intensity changes which indicate graft trophism. MRI also depicted correctly the femoral and tibial tunnel position and alignment, the presence of possible impingement with bone, the presence and extent of the healing reaction or of serum-hematic material in the intercondylar notch. The latter factor prevents the graft depiction, in which case the MR techniques providing the highest possible contrast in the different structures under examination are mandatory. Finally, MRI permitted to study possible associated capsuloligamentous or meniscal injuries and the state of femorotibial and femoropatellar chondral covering, the presence of articular synovia changes and the amount of possible joint effusion. We believe that MRI exhibited a high standard of sensitivity, versatility and diagnostic accuracy in the examination of surgical patients submitted to arthroscopic PCL reconstruction. Further studies and long-term follow-up will help define the use of MRI in these patients.

Adolescent↗
PubMed2001

Magnetic resonance imaging of the chest.

Thoracic magnetic resonance imaging (MRI) has recently undergone important advances, and newer applications could expand the role of thoracic MRI. Existing and developing MRI techniques are described and compared to other imaging techniques with regard to imaging various thoracic regions, structures, and diseases. After an initial discussion of MRI techniques, the role of thoracic MRI in evaluation of the thoracic arteries and veins is described. The next section focuses on specific anatomic regions; namely, the lung, mediastinum, pleural space, thoracic inlet, and diaphragm. The final section reviews some novel techniques that may improve our ability to visualize the pulmonary parenchyma and mediastinum.

Aortic Diseases↗
PubMed1991

Corpus callosum morphology in attention deficit-hyperactivity disorder: morphometric analysis of MRI.

Although behavioral evidence provides support for the notion that attention deficit-hyperactivity disorder (ADHD) is related to central nervous system dysfunction, there is little direct evidence to reveal which neurometabolic systems or brain structures are involved. Recent magnetic resonance imaging (MRI) studies suggest that, compared to nondisabled controls, ADHD children may have a smaller right frontal region. Morphometric analysis of MRI scans was used in this exploratory study to determine whether correlated regional variation might exist in the corpus callosum of children with ADHD. While all MRI scans were judged to be clinically normal, morphometric analysis revealed that, compared to nondisabled controls, ADHD children had a smaller corpus callosum, particularly in the region of the genu and splenium, and in the area just anterior to the splenium. Interhemispheric fibers in these regions interconnect the left and right frontal, occipital, parietal, and posterior temporal regions. These results suggest that subtle differences may exist in the brains of children with ADHD and that deviations in normal corticogenesis may underlie the behavioral manifestations of this disorder.

Attention Deficit Disorder with Hyperactivity↗
PubMed2004

Magnetic resonance imaging and computed tomography in assessment of atherosclerotic plaque.

The two most promising noninvasive imaging modalities for the study of atherosclerosis are magnetic resonance imaging (MRI) and computed tomography (CT). Both have been shown to be capable of imaging vessel wall structures and differentiating various stages of atherosclerotic wall changes. MRI has been applied in various in vivo human studies to image atherosclerotic plaques in coronary arteries, carotid arteries, and aorta. The latest generation of multidetector row computed tomography (MDCT) systems allows for the noninvasive characterization of different plaque components in various vascular structures. MDCT allows evaluation of the whole arterial vasculature. In addition, MDCT has the ability to visualize the vessel wall and to give a quantitative measurement of calcified and noncalcified plaque. Using either technique, the repeatable, noninvasive study of atherosclerotic disease during its natural history and after therapeutic intervention will enhance our understanding of disease progression and regression. MDCT and MRI, therefore, may help in selecting appropriate treatments.

Carotid Artery Diseases↗
PubMed2005

Application of the OMERACT filter to scoring methods for magnetic resonance imaging of the sacroiliac joints and the spine. Recommendations for a research agenda at OMERACT 7.

Magnetic resolution imaging (MRI) is a promising tool in the assessment of inflammation and structural damage in clinical trials in ankylosing spondylitis (AS). The ASAS/OMERACT MRI in AS working group, a collaborative initiative of rheumatologists and musculoskeletal radiologists with a special interest in this field, collected data on all available scoring methods for both sacroiliac (SI) joints and spine, and tested them with respect to the OMERACT filter. These data were presented together with the technical specifications of all methods at the OMERACT 7 conference. In addition, the results of 2 separate experiments on the inter-reader reliability of scoring methods to assess activity in SI joints, and on the comparison of STIR sequence versus T1 post-gadolinium (Gd) sequence for the spine, were presented. Thereafter, 8 groups discussed these data and proposed a research agenda, each on a different topic. This information was reported back to all participants and a prioritized research agenda was compiled by voting. Research on scoring methods for assessing disease activity, in both the spine and SI joints, was considered most important. Research on assessing structural damage was considered less important. The specific process and results of this initiative are discussed.

Biomedical Research↗
PubMed2005

Object working memory deficits predicted by early brain injury and development in the preterm infant.

Children born preterm and of very low birth weight are at increased risk of learning difficulties and educational under-achievement. However, little is known about the specific neuropsychological problems facing these children or their neurological basis. Using prospective longitudinal data from a regional cohort of 92 preterm and 103 full-term children, this study examined relations between term MRI measures of cerebral injury and structural brain development and children's subsequent performance on an object working memory task at the age of 2 years. Results revealed clear between-group differences, with preterm children having greater difficulty encoding new information in working memory than term control children. Within the preterm group, task performance at the age of 2 years was related to both qualitative MRI measures of white matter (WM) injury and quantitative measures of total and regional brain volumes assessed at term equivalent. Bilateral reductions in total tissue volumes (%region) of the following cerebral regions were specifically related to subsequent working memory performance: dorsolateral prefrontal cortex, sensorimotor, parietooccipital and premotor. Associations between total cerebral tissue volumes at term (adjusted and unadjusted for intracranial volume) persisted even after the effects of WM injury were taken into account. This suggests that early disturbance in cerebral development may have an independent adverse impact on later working memory function in the preterm infant. These findings add to our understanding of the neuropathological pathways associated with later executive dysfunction in the very preterm infant.

Brain↗
PubMed2001

Magnetic resonance imaging findings of vascular malformations of the lower extremity.

Vascular malformations are congenital lesions resulting from a defect during embryogenesis. Magnetic resonance imaging (MRI) is a very effective method for demonstrating detailed information regarding involved structures, extent, and flow characteristics of vascular malformations. In previous MRI studies, most of the emphasis is laid on the difference between high- and low-flow lesions, whereas little detailed information is available about the extent of local tissue involvement. These additional characteristics may influence the approach in treating these malformations and improve understanding of the pathogenesis. We retrospectively reviewed MRI scans of 40 patients with vascular malformations of the lower extremity. Thirty-four patients had low-flow lesions, and six had high-flow lesions. Of the low-flow lesions, 23 patients (67.6 percent) had muscle infiltration, with four of the six high-flow lesions having muscle infiltration. Nine of the 11 male patients (81.8 percent) with low-flow lesions had associated muscle infiltration, in comparison with 14 of the 23 female patients (60.9 percent) with low-flow lesions (p = 0.206). Eighty percent of the vascular malformations located on the thigh with muscle involvement had involvement of the anterior muscle group, whereas 86.6 percent of the patients with a vascular malformation located on the leg and with associated muscle involvement had at least the posterior muscle group involved (p = 0.0049). Ten patients (25 percent) of the whole group had bone infiltration. Low-flow lesions often had multifocal lesions (20.6 percent), whereas associated muscle atrophy was visible in 10 low-flow lesions and in two high-flow lesions. In low-flow lesions with muscle infiltration (n = 23), 43 percent (n = 10) had associated surrounding muscle atrophy (p = 0.009). Hypertrophy of the subcutaneous tissue was visible in 11 low-flow patients (32.4 percent). The high amount of muscle and bone involvement in vascular malformations of the lower extremity is emphasized with this study. Of particular interest was the difference in affected muscle groups. The angiosome concept is used to explain this preponderance, and we feel the angiosome concept could also be used when assessing possible intervention. The surrounding muscle atrophy and multifocal nature of these anomalies are further important considerations when assessing the possibility of intervention.

Adolescent↗
PubMed1999

Depression in Parkinson's disease: brainstem midline alteration on transcranial sonography and magnetic resonance imaging.

Recent studies using transcranial sonography (TCS) have provided evidence of alterations in the mesencephalic midline structures in patients with unipolar depression and depression in Parkinson's disease (PD), suggesting an involvement of the basal limbic system in primary and secondary mood disorders. This study tested the hypothesis of brainstem midline abnormality in depression and investigated 31 PD patients by magnetic resonance imaging (MRI) and TCS. Signal intensity of the pontine and mesencephalic brainstem midline was rated on T2-weighted images and measured by relaxometry. In addition, two blinded investigators assessed the echogenicity of the brainstem midline by TCS. The severity of motor symptoms and depression were graded independently using standard research scales. Rating of signal intensity and T2 relaxometry of the pontomesencephalic midline structures revealed significant difference between depressed and nondepressed PD patients (P < 0.05). This corresponded to a significant reduction in mesencephalic midline echogenicity of depressed PD patients on TCS images. No correlation was found between raphe signal intensity, T2 relaxation times, or TCS echogenicity and the severity of motor symptoms or depression. This study is the first to show changes in signal intensity and T2 relaxation time of the pontomesencephalic midline structures on MRI in depressed PD patients confirming previous TCS findings. As these midline structures comprise fiber tracts and nuclei of the basal limbic system, the findings may support the hypothesis of an alteration in the basal limbic system in mood disorders.

Aged↗
PubMed2000

Frequency of cochlear enhancement on magnetic resonance imaging in patients with autoimmune sensorineural hearing loss.

OBJECTIVE: To evaluate magnetic resonance imaging (MRI) scans for enhancement of inner ear structures of patients with sensorineural hearing loss and documented antibodies to the 68-kd inner ear antigen. STUDY DESIGN: Retrospective case review with reexamination of MRI scans. SETTING: Outpatient office. PATIENTS: Thirty-five patients with autoimmune sensorineural hearing loss defined by audiograms documenting a sensorineural hearing deficit in one or both ears and the presence of an anti-inner ear antibody (68-kd band) in serum samples who underwent precontrast and postcontrast T1-weighted axial and coronal MRI scans of the inner ear, which were performed concurrently with the hearing loss. INTERVENTIONS: Diagnostic. MAIN OUTCOME MEASURES: Frequency and intensity of cochlear enhancement on MRI scans. RESULTS: One patient demonstrated +2 cochlear enhancement. However, that finding was thought to represent postoperative inflammatory change. CONCLUSION: No correlation was found between the presence of antibodies to inner ear antigen in patients with hearing loss and cochlear enhancement on MRI scans.

Autoantibodies↗
PubMed2003

[Prognostic value of MRI and 1H MRS in patients with temporal lobe epilepsy].

OBJECTIVE: To evaluate the prognostic value of hippocampal MRI scan, MRI volumetry and 1H MRS in patients with temporal lobe epilepsy (TLE). METHODS: 50 intractable TLE patients operated in Huashan hospital were studied. Before surgery, traditional MRI scans were used to exclude tumor and vascular malformation of the brain. All patients were examined by tilted coronal images which were perpendicular to the long axis of the hippocampus, using T1-weighted, T2-weighted and FLAIR sequence. MRI volumetric measurement of both hippocampal formation were performed. 38 patients also took 1H MRS scan. Unilateral anterior temporal lobectomy was performed in all patients and pathology showed different degrees of hippocampal sclerosis. The prognosis was categorized into three grades with grade I being assigned to the group of good outcome, and grade II and III being assigned to the bad outcome group. Correlative analysis between the results of several examinations and the prognosis were performed respectively. RESULTS: MRI-positive cases with hippocampal scans were about 84% of the 50 cases. Hippocampal atrophy, increase of signal intensity or the loss of internal morphological structure were detected. 98% of the MRI-positive patients had good outcome, and 38% of the MRI-negative patients had good outcome. The prognosis between MRI-positive group and MRI-negative group had significant difference (chi(2) = 23.00, P = 0.000). Among the right-side operated cases, the average hippocampal volume on the operated side of the bad outcome group was larger than that of the good outcome group. While among the left-side operated cases, the hippocampal volume on the non-operated side of the bad outcome group was smaller than that of the good outcome group. Significant differences were found in statistics respectively. In both groups, prognosis was found to be statistically related to the DHF value (difference of bilateral hippocampal volume). The DHF value of the good outcome group was larger than that of the bad outcome group. 38 patients took 1H MRS examination. The average NAA/(Cr + Cho) ratio on the operated side of the patients in the bad outcome group was greater than that of the good outcome group. The average NAA/(Cr + Cho) ratio on the contralateral side of the patients in the bad outcome group was lower than that of the good outcome group. But no significant differences were found in statistics respectively. 90% cases of MRS unilateral abnormalities had good outcome, while 77% cases of MRS bilateral abnormalities had good outcome. But no statistically significant difference was found among different groups (chi(2) = 0.493, P = 0.781). CONCLUSION: Hippocampal MRI scan, MRI volumetry and 1H MRS may be used as prognostic tools in TLE patients before surgery. The combination of several noninvasive methods before surgery can help choose suitable patients for surgery, and, as a result, improve surgical outcome.

Adolescent↗
PubMed1996

The snapping hip: clinical and imaging findings in transient subluxation of the iliopsoas tendon.

OBJECTIVE: To define the clinical, ultrasonographic and magnetic resonance imaging (MRI) findings in patients with painful snapping of the hip secondary to transient subluxation of the iliopsoas tendon. PATIENTS AND METHODS: Seven patients, ranging in age from 17 to 30 years, with a total of eight painful snapping hips were examined with static and dynamic ultrasonography and MRI during hip motion producing the painful snapping. The duration of symptoms, the level of disability and the response to therapy were recorded. RESULTS: Static ultrasonography showed thickening of the iliopsoas tendon (tendinitis) in two cases and a peritendinous fluid collection in two cases. In all cases dynamic ultrasonography of the iliopsoas tendon during hip motion showed distinct abnormal motion of the tendon corresponding temporally to the painful palpable and audible sensation. MRI showed normal intra-articular structures in all cases, tendinitis in two cases and iliopsoas bursitis in one case. Clinically, subluxation of the iliopsoas tendon is a chronic (mean duration of symptoms in this series, 23 months) disabling condition that may be relieved by surgical tendon release. CONCLUSIONS: Dynamic ultrasonography is useful for detecting transient subluxation of the iliopsoas tendon in patients with a painful snapping hip. MRI is useful for excluding intra-articular abnormalities in patients with this condition.

Adolescent↗
PubMed2002

MR imaging of soft-tissue masses of the foot.

As with other parts of the musculoskeletal system, the soft tissues of the foot can be affected by a wide variety of pathologic entities including trauma, congenital abnormalities, infections, and neoplastic disorders. While plain radiographs are usually the initial examination for evaluation of pathology, magnetic resonance imaging (MRI) is critical to evaluate for abnormalities within the ligaments, tendons, and other nonosseous structures within the foot. The constellation of clinical and MRI findings often allows a relatively specific diagnosis to be rendered. This article discusses both benign and malignant processes within the soft tissues of the foot and presents their characteristic imaging findings with MRI.

Connective Tissue↗
PubMed1989

[Space-occupying lesions of the pineal region in magnetic resonance tomography].

Preoperative CT and MRI studies of 24 patients with space-occupying lesions of the pineal region were analysed. MRI demonstrated all 24 lesions, whereas CT could detect only 20 out of 24. MRI was superior to CT in assessment of size, localisation and relation to adjacent structures. No significant difference was found between CT and MRI in preoperative prediction of tumour histology.

Brain Neoplasms↗
PubMed1998

Cerebral activation in malformations of cortical development.

Malformations of cortical development (MCD) are an important aetiology of localization-related epilepsy. Previous MRI and [11C]flumazenil PET studies have demonstrated widespread structural and neuroreceptor abnormalities beyond the region of MCD that is visually apparent on MRI. We investigated the ability of brain regions affected by MCD to participate in normal cognitive and motor tasks and compared the responses seen in such patients with those in normal subjects. We studied five patients known to have MCD affecting the occipital region and seven normal subjects using H2 (15)O PET whilst they were performing a visual attention task. We also studied five right-handed patients known to have MCD affecting the left frontal lobe and seven right-handed normal subjects, using H2 (15)O PET whilst they were performing a motor learning task with the right hand. The patient and normal control data were examined using statistical parametric mapping to determine the ability of the brain region affected by MCD to participate in the task and also to detect evidence for atypical organization of cortical function in association with the MCD. Eight of the ten patients with MCD showed significant alteration of relative regional cerebral blood flow during the task compared with 'rest' in the affected brain region. These regions included focally dysgenetic cortex, the cortex lining schizencephalic clefts, heterotopic bands, subependymal grey matter heterotopia, and the cortex overlying band and subependymal heterotopia. In addition there was a significant alteration in the overall activation pattern in five patients compared with the normal control groups; in all five patients this atypical organization involved regions of cortex that appeared entirely normal on MRI. We conclude that regions of MCD may participate in normal cognitive functions but widespread cortical atypical organization may be seen. These findings have implications for surgical planning in any such patients.

Adolescent↗