Minor cerebral alterations observed by magnetic resonance imaging in syndromic children with mental retardation.

OBJECTIVE: To evaluate the anomalies of the central nervous system (CNS) by magnetic resonance imaging (MRI) in normal subjects and in syndromic patients. METHODS AND MATERIAL: Seventy-three normal subjects and 50 different syndromic patients with mental retardation (from 3 months to 16 years) were studied utilizing several morphometric parameters (degree of myelination of the white matter, evaluation of liquoral spaces, septo-caudate distance, Evans index, Aboulezz method, and length, width and angles of corpus callosum). RESULTS: A high frequency of anomalies of the corpus callosum, the Chiari anomaly and alterations either of the white matter or of the ventricular and periencephalic system have been observed. CONCLUSION: The authors point out the importance of cerebral MRI in the study of CNS in patients with malformation syndromes. The present research, carried out on a large number of both normal subjects and patients with malformation syndromes, represents one of the first systematic studies in this field.

Cerebral magnetic resonance imaging: normal parameters of central nervous system in the pediatric age.

Normal standards are required in order to evaluate minimal morphological changes in CNS disorders in childhood. We therefore investigated several morphometric parameters (white matter evaluation, ventricular and periencephalic liquoral spaces, septocaudate distance, Evans index, morphological evaluation of corpus callosum, Chamberlain line) in 52 non-neurological subjects by cerebral MRI.

Brain involvement in myotonic dystrophy: MRI features and their relationship to clinical and cognitive conditions.

A prospective, case-control study was carried out on 25 patients with myotonic dystrophy (MyD) and 25 healthy subjects using brain magnetic resonance imaging (MRI). The frequency and severity of white matter hyperintense lesions (WMHL) and brain atrophy in MyD patients were compared with their clinical features and cognitive impairment using an extensive neuropsychological battery. Eighty-four per cent of MyD patients showed WMHL, compared with 16% of controls (p < 0.0001). These lesions involved all cerebral lobes, without hemispheric prevalence. Twenty-eight per cent of MyD patients also showed particular WMHL at their temporal poles. Myotonic patients had significantly more cortical atrophy than controls. No relationship between atrophy and WMHL was found on the MRI scans. The extent of brain abnormalities (WMHL or atrophy) was not correlated to age, disease duration, physical disability or severity of neuropsychological impairment. Central nervous system abnormalities revealed by MRI appear to be an almost constant feature of MyD, but they are not found to be related to clinical or cognitive parameters. Their nature is still unclear: some of them, located at the temporal poles, seem to be characteristic of the disease, while others small, diffuse WMHLs, similar to the age related alterations revealed by MRI occurring during young and adult age in MyD patients.

MRI and pathological examination of post-mortem brains: the problem of white matter high signal areas.

We examined 21 brains from individuals more than 65 years of age by MRI and neuropathological methods to study the frequency and morphology of white matter changes. There were 16 brains from neurologically normal subjects (Group 1) while the remaining 5 (Group 2) had neurological disturbances. In Group 1 MRI showed high signal areas in the periventricular white matter in 12 brains and in the deep white matter in 9. All had focal areas, with confluent zones in 4; 3 cystic infarcts were also detected. Neuropathology in this Group showed periventricular changes of variable extent in all cases, vacuolated myelin around the perivascular spaces in 14 and degenerate myelin in 4. Macroscopic inspection showed 3 cystic lacunar infarcts, while areas of recent infarction were present on histology in 2. Four of the Group 2 brains had periventricular MRI changes; high signal areas in deep white matter were focal in 2 and confluent in 1. Cystic infarcts were detected in 3 cases. Neuropathology showed periventricular changes in all the brains; in 4 myelin around the perivascular spaces was vacuolated while degenerate myelin was demonstrated in 1. There were also old (1) and recent (2) lacunar infarcts. High signal areas in the white matter thus have different histological backgrounds but only in a minority of cases do they seem to be of pathological significance and, as a rule, they are not related to the presence of neurological disturbances. Correlative MRI-neuropathological studies are helpful for characterising abnormalities detected by techniques, like MRI, which are sensitive but not very specific.

[The current role of neuroradiology in evaluating malformation syndromes]. / Ruolo attuale della neuroradiologia nelle valutazioni delle sindromi malformative.

CT and MRI play complementary roles in the study of malformation syndromes in pediatric age: CT in particular is indispensable for adequately assessing the skeletal picture in subjects suffering from cranio-facial malformations, while MRI allows a morphological study and supplies informations on the maturation state of the white matter.

Acute monophasic focal demyelinating diseases of the central nervous system: longitudinal clinico-neuroradiological study of two patients.

We report the clinical features and laboratory-instrumental findings in two patients with acute monophasic demyelinating disease with focal clinical expression: one case of incomplete cervical transverse myelitis and one of focal supratentorial encephalitis. We describe the clinical course and evolution of the neuroradiological findings (CT and MRI) and discuss their pathological meaning and diagnostic value.

Cerebral MRI in two brothers with mucopolysaccharidosis type I and different clinical phenotypes.

We describe a cerebral MRI study of two brothers with mucopolysaccharidosis type I. They are of similar physical appearance, but the younger is severely mentally retarded while the elder is of normal intelligence. MRI shows characteristic abnormalities in the CNS, but it is not yet possible to establish a correlation between them and the mental retardation.

Haemodynamic changes following carotid occlusion: MRI angiography and transcranial Doppler patterns.

To see the signal changes in MR angiography (MRA) when occlusions or severe stenoses of carotid arteries occur and to relate these data with the velocity values provided by transcranial Doppler sonography (TCD), 20 patients showing symptomatic or asymptomatic unilateral carotid obstructions underwent both MRA and TCD after digital angiography investigation. No MRA signal was recorded immediately downstream from the carotid occlusion. Low flow velocity values in the carotid siphon and middle cerebral artery (MCA) ipsilateral to the carotid obstruction were associated with altered MRA signals corresponding to the same vessels. Turbulence phenomena induced by reversed flow in the anterior cerebral artery induced MRA signal impairments. In carotid occlusions, there may be a relationship between the MRA patterns and the flow velocity variations detected by TCD, but the two approaches have to be applied together since they provide complementary information.