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M Dichgans

Publications and source records attributed to M Dichgans.

At least 37 records · Page 2Linked to original sources
PubMed1999

Quantitative MRI in CADASIL: correlation with disability and cognitive performance.

OBJECTIVE: To study correlations between total lesion load on brain MRI and clinical features, and to evaluate the influence of demographic variables on quantitative MRI variables in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). BACKGROUND: CADASIL is a hereditary form of small-vessel disease caused by mutations within the Notch3 gene. MRI abnormalities have been found both in asymptomatic and symptomatic CADASIL individuals. METHODS: Quantitative measurements on cerebral MRI were performed in 64 CADASIL individuals. MRI lesions were quantified using a semi-automated segmentation technique based on local thresholds. RESULTS: MRI total lesion volume correlated significantly with disability (Rankin Scale) on both T1- and proton density (PD)-weighted images. There was a significant inverse correlation between total lesion volume and overall cognitive performance as determined by the Mini-Mental State Examination. Age but not sex was correlated with lesion load both on T1- and PD-weighted images. There was no detectable influence of the Notch3 genotype on quantitative MRI variables. CONCLUSIONS: This study demonstrates correlations between MRI lesion volume and clinical characteristics in CADASIL. Longitudinal studies are now warranted to investigate whether quantitative MRI could be used as an adjunct outcome measure in future therapeutic trials in CADASIL.

Adult↗
PubMed1999

Bacterial meningitis in adults: demonstration of inner ear involvement using high-resolution MRI.

OBJECTIVE: To visualize the sites involved in audiovestibular dysfunction during bacterial meningitis in adults and to relate these findings to the extent of hearing impairment and vestibular dysfunction. BACKGROUND: Hearing impairment is among the most frequent complications of bacterial meningitis. METHODS: High-resolution MRI (HR-MRI) of the inner ear was performed in seven adult patients with hearing loss as a complication of bacterial meningitis. RESULTS: Five patients had unilateral (n = 1) or bilateral (n = 4) contrast enhancement of vestibulocochlear structures. The structures most frequently involved were the cochlear nerve (n = 9), the first cochlear turn (n = 9), the vestibulum (n = 9), and the semicircular canals (n = 7). There was a significant correlation between clinical and MRI findings: all nine ears with cochlear enhancement were deaf (hearing loss >90 dB), whereas none of the five ears with normal MRI findings had hearing losses of more than 90 dB (range, 30 to 70 dB; p = 0.0005). Vestibular dysfunction as revealed clinically and by quantitative vestibular function testing was found in six of seven patients (11 of 14 ears). Five of these patients (nine ears) also demonstrated enhancement of the vestibular organ on high-resolution MRI of the inner ear. CONCLUSIONS: High-resolution MRI can visualize the involvement of vestibulocochlear structures in bacterial meningitis in both cooperative and consciously impaired patients. These findings suggest a correlation between abnormalities on MRI and the extent of cochlear dysfunction.

Adolescent↗
PubMed1999

Spinocerebellar ataxia type 6: evidence for a strong founder effect among German families.

The authors found a strong geographic cluster of spinocerebellar ataxia type 6 (SCA6) families in the Northrhine-Westfalia area, suggesting a founder effect in the German SCA6 population. Genotyping with DNA markers linked to the CACNL1A4 gene on chromosome 19p13 revealed a common haplotype and shared allelic characteristics in the majority of German families. The observed founder effect may be related to the relative meiotic stability of CAG repeats in this type of autosomal dominant cerebellar ataxia.

Alleles↗
PubMed1999

Muscle and skin biopsies are a sensitive diagnostic tool in the diagnosis of CADASIL.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a microangiopathic syndrome. Although the defective gene has been identified, genetic analysis may be effort some due to its large size and various mutations. Providing a reliable diagnostic marker would therefore be helpful. Electron microscopy has revealed characteristic electron-dense granular deposits in the basal lamina of vessels of patients with CADASIL. We investigated the sensitivity of skin and muscle biopsies for diagnosing CADASIL. We examined 30 family members of three unrelated German families affected by CADASIL. In 14 of the 21 affected individuals we performed skin and muscle biopsies; two patients were clinically asymptomatic. Under electron microscopy all muscle and skin biopsy specimens showed patches of granular and electron-dense material in the basal layer of both arterioles and capillaries. These findings confirm that general microangiopathy is a typical feature of this syndrome and is present in the early phase of the disease with or without clinical manifestation. Thus, as electron microscopy of skin biopsy specimens can establish the diagnosis of CADASIL with high certainty, it may be considered the method of first choice.

Adult↗
PubMed1999

Familial hemiplegic migraine with cerebellar ataxia and paroxysmal psychosis.

Familial hemiplegic migraine is a rare autosomal dominant disorder associated with stereotypic neurologic aura phenomena including hemiparesis. So far two chromosomal loci have been identified. Families linked to the chromosome 19 locus display missense mutations within the CACNL1A4 gene. Here we report on a family with familial hemiplegic migraine and cerebellar ataxia with recurrent episodes of acute paranoid psychosis with anxiety and visual hallucinations associated with migraine attacks. Based on the clinical and haplotype evidence indicating linkage to chromosome 19 in this family, we hypothesize that a dysfunction of the mutated calcium channel may be involved not only in the development of hemiplegic migraine but also in the acute psychotic episodes observed in these patients.

Adolescent↗
PubMed1999

Characteristic MR lesion pattern and correlation of T1 and T2 lesion volume with neurologic and neuropsychological findings in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL).

BACKGROUND AND PURPOSE: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an arteriopathy related to a genetic defect of the notch 3 gene on chromosome 19. The purpose of this study was to evaluate lesion distribution and volume using MR imaging and to correlate the lesion volume with the neurologic and neuropsychological findings. METHODS: Twenty members of two families (14 with CADASIL as determined by linkage analysis, six healthy) were studied with MR imaging. Two observers evaluated the MR findings semiquantitatively and quantitatively. MR results were then correlated with neurologic and neuropsychological findings. RESULTS: A typical pattern of lesion distribution in patients with CADASIL was found: the frontal lobe was the site with the highest lesion load, followed by the temporal lobe and the insula. The total lesion volume on T1-weighted MR images correlated significantly with the degree of disability and the degree of impairment in neuropsychological functions (including attention, memory, and conceptual and visuospatial functions). CONCLUSION: In CADASIL patients, a common pattern of cerebral lesion distribution is found. The total T1 lesion volume is an important parameter to correlate with disability, as it may prove to be helpful in predicting the natural history of the disease.

Adult↗
PubMed1998

Genomic sequences of aldolase C (Zebrin II) direct lacZ expression exclusively in non-neuronal cells of transgenic mice.

Aldolase C is regarded as the brain-specific form of fructose-1, 6-bisphosphate aldolase whereas aldolase A is regarded as muscle-specific. In situ hybridization of mouse central nervous system using isozyme-specific probes revealed that aldolase A and C are expressed in complementary cell types. With the exception of cerebellar Purkinje cells, aldolase A mRNA is found in neurons; aldolase C message is detected in astrocytes, some cells of the pia mater, and Purkinje cells. We isolated aldolase C genomic clones that span the entire protein coding region from 1.5 kb 5' to the transcription start site to 0.5 kb 3' to the end of the last exon. The bacterial gene, lacZ, was inserted in two different locations and the constructs tested in transgenic mice. When the protein coding sequences were replaced with lacZ, three of five transgenic lines expressed beta-galactosidase only in cells of the pia mater; one line also expressed in astrocyte-like cells. When lacZ was inserted into the final exon (and all structural gene sequences were retained) transgene expression was observed in astrocytes in all regions of the central nervous system as well as in pial cells. Thus, with the exception of Purkinje cell expression, the behavior of the full-length transgene mimics the endogenous aldolase C gene. The results with the shorter transgene suggest that additional enhancer elements exist within the intragenic sequences. The absence of Purkinje cell staining suggests that the cis elements required for this expression must be located outside of the sequences used in this study.

Animals↗
PubMed1998

The phenotypic spectrum of CADASIL: clinical findings in 102 cases.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an increasingly recognized autosomal dominant disorder that leads to cerebrovascular manifestations in early adulthood. This study delineates the phenotypic spectrum and the natural history of the disease in 102 affected individuals from 29 families with biopsy-proven CADASIL. Recurrent ischemic episodes (transient ischemic attack [TIA] or stroke) were the most frequent presentation found in 71% of the cases (mean age at onset, 46.1 years; range, 30-66 years; SD, 9.0 years). Forty-eight percent of the cases had developed cognitive deficits. Dementia (28%) was frequently accompanied by gait disturbance (90%), urinary incontinence (86%), and pseudobulbar palsy (52%). Thirty-nine patients (38%) had a history of migraine (mean age at onset, 26.0 years; SD, 8.2 years), which was classified as migraine with aura in 87% of the cases. Psychiatric disturbances were present in 30% of the cases, with adjustment disorder (24%) being the most frequent diagnosis. Ten patients (10%) had a history of epileptic seizures. To delineate the functional consequences of ischemic deficits, we studied the extent of disability in different age groups. The full spectrum of disability was seen in all groups older than age 45. Fifty-five percent of the patients older than age 60 were unable to walk without assistance. However, 14% in this age group exhibited no disability at all. Kaplan-Meier analysis disclosed median survival times of 64 years (males) and 69 years (females). An investigation of the 18 multiplex families revealed marked intrafamilial variations.

Adult↗
PubMed1997

CADASIL: skin biopsy allows diagnosis in early stages.

OBJECTIVES: Our aim was to investigate the diagnostic impact of skin biopsies in CADASIL patients. MATERIALS AND METHODS: Eight consenting CADASIL patients belonging to a German-Caucasian kindred were assessed clinically, genetically, by MRI and skin biopsy. Skin biopsy results were compared to 5 patients suffering from sporadic leucoencephalopathies (control group). RESULTS: Six CADASIL patients presented with symptoms ranging from migraine to severe tetraparesis with dementia. Two clinically unaffected patients had abnormal MRIs. On MRI 7 patients showed various degrees of leucoencephalopathy. One 22-year-old woman with migraine had a normal MRI. Granular, electron dense, osmiophilic material (GEM) was found in skin biopsies of all 8 patients including the 22-year-old woman with migraine and a normal MRI. As shown by genetic linkage analysis she was carrying the disease haplotype. GEM was not found in the control group. CONCLUSION: Our findings substantiate the impact of skin biopsies in defining the carrier status in CADASIL families.

Adult↗
PubMed1996

Identification of a key recombinant narrows the CADASIL gene region to 8 cM and argues against allelism of CADASIL and familial hemiplegic migraine.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CA-DASIL) is a nonarteriosclerotic, nonamyloid angiopathy characterized by recurrent subcortical ischemic strokes starting in midadulthood and frequently leading to pseudobulbar palsy and dementia. The disease locus has recently been mapped to chromosome 19q12. We have identified a chromosomal crossover in a clinically affected family member, which refines the localization of the CADASIL disease locus. Multipoint linkage analysis established the best estimate for the gene locus within an 8-cM interval bracketed by D19S226 and D19S222. This estimate strongly argues against allelism of CADASIL and familial hemiplegic migraine.

Alleles↗
PubMed1995

[Hereditary CADASIL cerebral arteriopathy. Report of a family].

We describe two members of a German family with cerebral autosomal dominant arteriopathy (CADASIL), which is characterized by recurrent subcortical ischemic strokes, mild dementia and leukoencephalopathy. The clinical features of the disease are suggestive of Binswanger's subcortical arteriosclerotic encephalopathy. However, it differs by the lack of hypertension and familial aggregation with autosomal dominant inheritance. Magnetic resonance imaging (MRI) of the brain shows subcortical ischemic infarcts affecting the periventricular white matter, the basal ganglia and the brain stem. On T2-weighted imaging, areas of hyperintensity were found in the white matter of both cerebral hemispheres with preponderance of frontal and anterotemporal regions. We assume that the underlying disease in this family is CADASIL with subcortical infarcts and leukoencephalopathy. The recently assigned disease locus on chromosome 19 was confirmed in this family. A treatment trial with acetylsalicylate was started in the affected members of the family.

Adult↗
PubMed1994

[Variants of Todd's paralysis: postictal apraxia and prolonged postictal hemineglect].

Todd's post-epileptic paralysis is a well-known complication after focal or generalized epileptic seizures. The underlying pathophysiology, however, is still unknown. Commonly, it is associated with a hemiparesis, usually lasting minutes or hours, rarely as long as two days, with subsequent complete remission. We report 2 patients with unusual and variant post-epileptic syndromes which have not been previously described in the literature: first, an ideomotor limb apraxia, and second, a severe hemineglect syndrome. Each syndrome lasted up to 70 hours after the seizure and was completely reversible.

Adult↗
PubMed1980

[Treatment and late results of 33 fractures of the pilon tibialis (author's transl)].

Report about 33 patients with fractures of the pilon tibialis. Most of the fractures were treated surgically. In half of all cases severe destructions of the joint were found, the bone was broken into pieces. In eight patients compound fractures were seen; twelve fractures were observed in polytraumatized patients. In 18 patients a follow-up could be done. Only in seven cases the results were good. In six cases the outcome was satisfying, in five cases the results were bad. The reasons for unsatisfying late results are discussed.

Adolescent↗