Involvement of the basilar artery in diabetes mellitus: an MRI study of brainstem infarctions.

The relationships among diabetes mellitus (DM), brainstem infarctions (BSIs) and involvement of the basilar artery (BA) were investigated in 254 patients with acute cerebral infarctions detected on magnetic resonance (MR) imaging. Radiological findings included lesion topography and size (mm(2)) of BSIs on MR images, and the extent of BA stenosis measured by MR angiography. Adjusted logistic regression analyses showed that DM (OR 4.018; p = 0.0006) and BA stenosis (OR 1.003 per 1 mm; p < 0.0001) had an independent association with the incidence of BSIs, but the lesion size of the BSIs was only associated with BA stenosis (ß coefficient 0.280; p < 0.0001). Diabetic patients showed significantly more frequent isolated pontine infarctions and a lesser degree of BA stenosis (p < 0.005) compared to non-diabetic patients. Preferential involvement of the pons and smaller vessels may be characteristics of diabetic patients.

[Bulbar-onset amyotrophic lateral sclerosis (ALS) with isolated agraphia].

We reported the two cases with bulbar-onset ALS showing isolated agraphia without overt dementia and aphasia. Patient 1 was a 69-year-old man and patient 2 was an 81-year-old woman, and both were right-handed. Each patient developed dysarthria as an initial symptom followed by dysphagia, and neurological examinations showed atrophy and fasciculation of the tongue with upper and lower motor-neuron involvement of the extremities. These characteristic features with electromyographic evidence including widespread acute and chronic denervation led to a diagnosis of bulbar-onset ALS. Around 1 year after the onset of ALS, dysarthria was mild enough to allow oral communication enabling the determination that aphasia was absent with well preserved confrontation naming, repetition, reading and comprehension. The patients were polite without abnormal behavior or character change, and their general intelligence was also well preserved with excellent scores on the Mini Mental State Examination (30 and 27 points for patients 1 and 2, respectively) and Frontal Assessment Battery (16 points for each patient). However, spontaneous writing and dictation revealed abundant writing errors characterized by omission of kana letters and paragraphia of kana and kanji letters in both patients. Some syntactic errors were also observed in writing but in spoken language. A letter-number effect on writing errors was observed in patient 1. Copying of letters or words was intact and structure and orientation of written letters was well preserved, indicating the absence of constructional, apraxic or spatial feature of agraphia. Single photon emission computed tomography demonstrated reduced uptake in the bilateral frontotemporal lobes, predominantly in the left hemisphere, with less evident alternation in magnetic resonance imaging. Our results suggest that patients with bulbar-onset ALS may develop isolated agraphia as a single-domain cognitive impairment, preceding the clinical manifestation of aphasia or dementia. We speculate that the main responsible region might be the posterior part of the middle and inferior frontal gyri including Exner's writing center and Broca's area beyond the primary motor cortex.

Central pontine lesions observed with MRI in four diabetic patients.

We report four diabetic patients with a central pontine lesion on magnetic resonance imaging (MRI). All patients also had hypertension, diabetic neuropathy and nephropathy, and three had chronic hepatitis C. Their neurological symptoms were disproportionately mild compared with the MRI features, which were of high intensity on T2-weighted images, but were less prominent on T1- and diffusion-weighted images. A subclinical pontine lesion was found in two patients who had undergone MRI previously. We consider that diabetes mellitus is an important factor for developing a pontine lesion with or without symptoms, probably in association with hepato-renal problems and hypertension.

Agraphia in bulbar-onset amyotrophic lateral sclerosis: not merely a consequence of dementia or aphasia.

The clinical significance and characteristics of writing errors in bulbar-onset amyotrophic lateral sclerosis (ALS) are not clear. We retrospectively investigated writing samples in 19 patients with bulbar-onset ALS without preceding extra-motor symptoms. Co-development of dementia and/or aphasia was also explored and single photon emission computed tomography (SPECT) images of the brain were reviewed. As a result, a high prevalence of writing errors (15 of the 19 patients) was found. Of note were isolated writing errors with neither dementia nor aphasia verified in 2 patients whose dysarthria was mild enough to evaluate spoken language. The remaining 13 patients also showed agraphia, but either dysarthria was too severe to evaluate aphasia or frontotemporal dementia (FTD)-like features co-existed. Of these patients, one who initially lacked dementia subsequently developed FTD-like features. The frequent writing errors were omission or substitution of kana letters and syntactic errors. SPECT images showed bilateral or left-side dominant hypoperfusion in the frontotemporal lobes as a consistent feature. These results show that patients with bulbar-onset ALS frequently exhibit agraphic writing errors and that these are not merely consequences of dementia or aphasia. However, these writing errors may indicate the involvement of frontotemporal language-related areas beyond the primary motor cortex.

Do lesions involving the cortical cholinergic pathways help or hinder efficacy of donepezil in patients with Alzheimer's disease?

AIMS: To investigate the influences of vascular lesions detected by MRI, lesions involving the cortical cholinergic pathways and hippocampal thickness on therapeutic responsiveness to donepezil in patients with Alzheimer's disease (AD). METHODS: The study cohort contained 67 patients with probable AD. We used the revised Hasegawa Dementia Rating (HDS-R) and the Clock Drawing Test (CDT) to evaluate drug efficacy for 24 months. The Cholinergic Pathways Hyperintensities Scale (CHIPS), a newly developed visual scale, was used to semiquantify lesions on the cholinergic pathways. RESULTS: Over the 24-month period, the results of the CDT showed more apparent and constant association with white matter hyperintensities (WMH) and lesions on the cholinergic pathways than the HDS-R. WMH may enhance, while lesions on the cholinergic pathways may attenuate sensitivity to donepezil treatment when judged by the CDT. No apparent association between the thicknesses of hippocampi with baseline cognition or therapeutic responsiveness to donepezil was found. CONCLUSION: Donepezil may be more efficacious when further executive dysfunction caused by WMH is added to AD dementia and less so when cholinergic reserves are further impinged upon by lesions involving the cortical cholinergic pathways.

[Detection of micro mutation in dystrophin gene of DMD female carrier].

We attempted to identify a mutation in dystrophin gene in a female patient who was suspected a Duchenne muscular dystrophy (DMD) carrier with muscle weakness of upper limbs and congestive heart failure. We examined the mutation hot spots in DMD gene, exon 3, 6, 8, 13, 17, 19, 43, 44, 45, 47, 48, 49, 50, 52, 60 by multiplex PCR which had been a diagnostic screening strategy, and detected an extra band in exon 43 product. We also detected an extra band in exon 43 products by SSCP analysis for detection of small mutations which could not be detected by multiplex PCR. As a result of sequencing a PCR product of an exon 43, we confirmed an allele having the insertion of a 2 base of AT in Intron42, which is described for the first time. Although we can not conclude that this insertion is responsible for DMD, but it may cause abnormal splicing. In carrier detection of DMD without genetic information of proband, it is difficult to detect mutations by multiplex PCR solely. Therefore, SSCP of PCR products are recommended to detect mutation in DMD carrier.