Search

Background: Familial hemophagocytic lymphohistiocytosis (FHL) is a rare multisystem congenital disorder characterized by uncontrolled proliferation and infiltration of activated lymphocytes and histiocytes, secreting high amounts of inflammatory cytokines; this may affect multiple organs including liver, spleen, lymph nodes, bone marrow, and central nervous system (CNS; Janka, Eur J Pediatr 166:95-109, 1)., Objective: The objective of this study is to describe the characteristics of the encephalopathy and to correlate the neuroradiological findings with the clinical symptoms and the treatment response in a child with FHL type 3 studied by total body computed tomography and by brain magnetic resonance (MR) and MR spectroscopy., Results: VF, a 14-month-old female, developed a full-blown FHL, with facial nerve palsy as the only CNS complication. Brain MR imaging showed several focal areas of pathological signal in the subcortical and periventricular white matter, left thalamus, cerebellum, and brain stem. Proton MR spectroscopy also demonstrated no elevated peak of Cho, no lactate peak, and elevated glutamine/glutamate complex. Moreover, an elevated N-acetyl aspartate (NAA) peak was detected. The follow-up MR study after hematopoietic stem cells transplantation showed a dramatic reduction of the lesions and normalization of the metabolic pattern at spectroscopy., Conclusion: Brain lesions and metabolic alterations documented by MR and spectroscopy during active FHL reverted during disease control achieved by therapy. more...

Objective: To evaluate, by using quantitative MRI metrics, subtle cortical changes in brains of patients with the adult form of myotonic dystrophy type I (DM1) who showed no or minimal abnormalities on MRI., Background: DM1 is an autosomal dominant multisystem disorder caused by the expansion of CTG repeats in the myotonic dystrophy-protein kinase gene. Mild to severe involvement of the CNS can be part of the clinical features of the disease. Several MRI studies have demonstrated that both focal white matter (WM) lesions and diffuse grey matter atrophy can be found in the brains of DM1 patients. However, whether these two processes are related or may occur independently is not clear., Design/methods: Ten genetically-proven DM1 patients who showed no or minimal abnormalities on MRI underwent a new brain MRI examination to obtain computerized measures of total and regional brain volumes normalized to head size and regional measurements of the magnetization transfer ratio (MTr)., Results: Normalized brain volumes (NBV) were significantly (p < 0.0001) lower in DM1 subjects than in a group of age- and sex-matched normal controls. Normalized cortical volumes (NCV) also were lower (p = 0.003) in DM1 subjects than in normal controls, whereas normalized WM volumes were not different between the two groups (p = 0.3). In agreement with this, values of MTr in the neocortex (cortical-MTr) were significantly (p = 0.006) lower in DM1 patients than in normal controls and this difference was not found in the WM tissue (p = 0.8)., Conclusions: Neocortical damage seems to be evident in the absence of visible WM lesions suggesting that a neocortical pathology, unrelated to WM lesion formation, occurs in DM1 brains. more...

Objectives: To assess structural and metabolic brain changes in subjects affected by Fabry disease (FD) or carrying the disease mutation., Background: FD is an X-linked metabolic disorder due to alpha-galactosidase A deficiency, which leads to storage of glycosphingolipids in many tissues and organs. Previous MR studies have shown structural and metabolic brain abnormalities in FD patients. It is not clear, however, whether tissue damage can be seen in both the brains of hemizygous and heterozygous and whether quantitative MR metrics are useful to monitor disease evolution., Design/methods: We studied 4 males and 4 females with FD. Each subject underwent brain proton MRI/MR spectroscopic imaging (MRSI) examinations to obtain measures of total brain volumes, total brain lesion volumes, magnetization transfer ratios (MTr) in WM and central brain levels of N-acetylaspartate (NAA) to creatine (Cr). A second MR examination was performed in five subjects after 2 years., Results: Focal WM lesions were found in 2 males and 1 female. The MTr values were always low in the WM lesions of FD subjects (p < 0.001) and also were low in the normal-appearing WM of 2 affected males. Total brain volumes were never decreased in FD subjects. Brain NAA/Cr values were significantly (p = 0.005) lower in FD subjects than in normal controls and correlated closely with Rankin scale measures (r = -0.79). On follow-up examinations, no significant MR changes were found. However, the small changes in NAA/Cr correlated closely with changes in Rankin scores (r = -0.86)., Conclusions: Subtle structural and metabolic tissue damage can extend beyond WM lesions in FD subjects. Diffuse brain NAA/Cr decrease can be found in FD subjects in relation to the degree of their CNS involvement and its evolution over time. more...

Objective: . Involvement of the central nervous system (CNS) in systemic sclerosis (SSc) is rare. Proton magnetic resonance spectroscopy (1H-MRS) assesses in vivo cerebral metabolites. We investigated the biochemical modifications of the CNS in SSc., Methods: N-acetylaspartate/creatine ratio (NAA/Cr) and choline/creatine ratio (Cho/Cr) at right centrum semiovale (RCS) and at right basal ganglia (RBG) were evaluated by 1H-MRS in 12 patients with limited (lSSc) and 8 patients with diffuse SSc (dSSc) and 20 control subjects., Results: With 1H-MRS, a significant reduction of NAA/Cr ratio at RBG (p < 0.02) and at RCS (p < 0.002) was detected in SSc patients. Cho/Cr ratio was increased (p < 0.02) in the RCS, but not in RBG. In patients with lSSc, a significant reduction of NAA/Cr was detected in RCS but not in RBG., Conclusion: Evidence of neuroaxonal damage strongly suggests the existence of CNS involvement in SSc. more...

Background: Recent clinical and imaging studies have raised the hypothesis that patients with multiple sclerosis (MS) and the apolipoprotein E (ApoE) epsilon4 allele may have a more severe disease course than those without the ApoE epsilon4 allele. This seems to be related to more extensive tissue destruction and less efficient neuronal maintenance and repair in ApoE epsilon4 carriers., Objective: To evaluate the influence of different ApoE genotypes on brain tissue integrity in patients with relapsing-remitting MS (RRMS)., Design: We determined the ApoE genotype in 76 RRMS patients. Conventional T1-, T2-, and proton density-weighted magnetic resonance (MR) images were obtained for each patient and in a group of demographically matched healthy control subjects. On conventional T1-weighted MR images, an automated analysis tool was used to obtain total brain volumes normalized for head size (NBVs). Total brain lesion load was estimated on proton density- and T2-weighted MR images., Results: From the whole group of RRMS patients, we identified 18 with and 58 without the epsilon4 allele. Both patient groups were not significantly different in age, age of disease onset, clinical disability, and disease duration. Carriers of the epsilon4 allele showed significantly (P =.01) lower NBVs than controls and non-epsilon4 allele carriers. When a similar analysis was performed on only those patients with both very short disease duration and absence of clinical disability, NBV values were still significantly lower in RRMS patients with the epsilon4 allele than in those without it (P =.02) and in controls (P =.007). In contrast, RRMS patients with different ApoE genotypes did not show significant differences in values of total brain T2-weighted lesion volumes., Conclusions: The presence of significant NBV decreases only in the group of RRMS patients with the ApoE epsilon4 genotype provides new evidence that links ApoE epsilon4-related impaired mechanisms of cell repair and severe tissue destruction in MS. Results of the present study suggest that this negative influence of the ApoE epsilon4 genotype might be active from the earliest disease stages. more...

Objective: To assess CNS abnormalities in patients with Werner's syndrome (WS) using MR metrics specific for tissue damage., Background: WS is a rare autosomal recessive disorder that causes premature aging. The CNS involvement in this disease is still debated., Methods: Two siblings who showed signs of neurological involvement underwent MR spectroscopic imaging (MRSI) and magnetization transfer (MT) imaging. Also, on conventional T1-weighted MR images, measurements of total brain volume were performed., Results: Conventional MR images of both WS patients did not show abnormalities on visual inspection. However, both WS patients showed significantly lower values of normalized total brain volume and MT ratio in the white matter than age-matched normal controls. Also, proton MRSI showed significantly lower values of central brain NAA/Cr in WS patients than in normal controls., Conclusions: Our findings suggest that, despite normal appearance on conventional MRI, diffuse structural and metabolic tissue damage can be demonstrated in WS brains by means of sensitive MR methods even in patients with moderate or subclinical CNS involvement. more...

Objective: The aim of the present study was to assess and monitor brain damage in patients with pediatric onset systemic lupus erythematosus (SLE) using non-invasive techniques such as magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy (H-MRS)., Methods: Twenty-four SLE patients, both symptomatic or asymptomatic for central nervous system (CNS) involvement, and 20 controls were examined. Each individual underwent a diagnostic MRI using a 1.5 T Philips ACS-NT scanner including transverse T2-weighted (T2W) spin echo, transverse FLuid Attenuated Inversion Recovery (FLAIR), and sagittal T2W turbo spin echo 5 mm slices. In addition, single voxel proton MR spectroscopy localized on the supraventricular region was performed in all patients and controls. Patients were re-examined after one year., Results: 75% of SLE patients had clinical CNS involvement; 46% showed abnormal MRI (3 of them, in the absence of neurologic signs); 4 SLE patients showed N-acetylaspartate/Creatine (NAA/Cr) ratios significantly lower than the controls. Among 5 SLE patients examined at the onset of the disease, 1 had MRI alterations and another showed a decrease of NAA/Cr values. Three patients with relapses showed a correlation between the course of the disease and the NAA/Cr ratios., Conclusion: MRI and H-MRS are non-invasive techniques that might be useful, in some cases, in detecting CNS involvement in SLE patients and monitoring the disease course and efficacy of pharmacological treatment. more...

Cerebrotendinous xanthomatosis (CTX) is a rare disorder due to an inherited defect in the metabolic pathway of cholesterol. Early diagnosis of the disease is particularly important as patients benefit from therapy with chenodeoxycholic acid. Although the disease is clinically characterized by the concomitant presence of tendon xanthomas, juvenile cataracts and progressive neurological impairment, clinical features may vary greatly. Neuroradiological studies have suggested that the bilateral abnormality of the dentate nuclei could be typical of this disease. However, this finding has been seen inconsistently on conventional MRI. The dynamic of the CNS pathology in CTX is complex, and whether demyelination or axonopathy has primary importance in the pathogenesis of CTX pathology is not known. To clarify both neuroradiological and pathological issues, we performed combined brain MRI and spectroscopy examinations on 12 CTX patients. On conventional MRIs, bilateral hyperintensities of the dentate nuclei were clearly seen in nine out of 12 patients on T(2) -weighted MRIs, but were evident in all patients using a FLAIR sequence. On proton magnetic resonance (MR) spectroscopy, significant decreases in N: -acetylaspartate resonance intensities (P: <0.0001) and increases in lactate MR signals (P<0.05) were found in the group of CTX patients in large volumes of interest localized above the lateral brain ventricles and in the cerebellar hemispheres. Cerebral values of N -acetylaspartate resonance intensities showed a close correlation with patients' disability (Spearman rank correlation = -0.78, P<0.005). These results suggest that MR abnormalities in the dentate nuclei may be evident consistently in patients with CTX. Proton MR spectroscopy data demonstrated widespread axonal damage (as shown by the decrease in N -acetylaspartate) and diffuse brain mitochondrial dysfunction (as shown by the increase in brain parenchymal lactate) in patients with CTX. The close correlation seen between values of the putative axonal marker N-acetylaspartate and patients' disability scores suggests that proton MR spectroscopy can provide a useful measure of disease outcome in CTX. more...

Proton magnetic resonance spectroscopy (MRS) allows accurate and noninvasive biochemical assay of living tissues. In vivo measurements provided by MRS have greatly enhanced our understanding of the pathophysiology of dementia. Increases in choline and myo-inositol (markers of membrane turnover) have been demonstrated in several studies on patients with Alzheimer's disease (AD), suggesting the presence of a significant cellular membrane (and glial) pathology in this disorder. Large decreases in brain N-acetylaspartate (NAA) (a marker of neuroaxonal integrity) are commonly seen in AD as well as in other forms of dementia in cerebral gray and white matter, indicating the presence of significant axonal damage. Since greater NAA decreases have been demonstrated in brains of patients with clinically more severe disease, NAA could provide an index relevant to patients' clinical status. Brain metabolic changes can be independent of abnormalities detected by conventional magnetic resonance imaging (MRI), since proton MRS may show a normal metabolic pattern in patients with mild neurological impairment and severe MRI abnormalities. However, quantitative measurements of regional brain volumes can be useful in the diagnosis of dementia. Thus, proton MRS, alone or combined with new quantitative magnetic resonance techniques, can provide sensitive indices able to monitor disease progresson or effects of drug therapy. more...