Ken-ichi Tabata

Hereditary motor and sensory neuropathy associated with cerebellar atrophy (HMSNCA): Clinical and neuropathological features of a Japanese family

We report clinicopathological features of a Japanese family with hereditary motor and sensory neuropathy associated with cerebellar atrophy (HMSNCA). Four affected members from a single generation were examined. They shared common clinical features, including insidious onset in teenage, slowly progressive cerebellar ataxia, amyotrophy, sensory disturbance, and dementia. In addition, all the patients showed hypoalbuminemia and hyperlipidemia and a marked atrophy of the cerebellum on magnetic resonance images. Autopsy of the proband revealed a severe loss of Purkinje cells, degeneration of posterior columns and spinocerebellar tracts of the spinal cord, and a marked loss of myelinated and unmyelinated fibers in the peripheral nerves. We consider that HMSNCA is a distinct form of hereditary multisystem neuronal degeneration.

Withdrawal of levodopa and other risk factors for malignant syndrome in Parkinson's disease

A symptom complex identical to neuroleptic malignant syndrome (MS) is known to develop in patients with idiopathic Parkinsons disease (PD) or other forms of parkinsonism on long-term treatment with anti-parkinsonian drugs. In order to clarify the risk factors for parkinsonian MS, the authors retrospectively reviewed charts of consecutive inpatients with PD in the neurological departments at the three hospitals and found 16 episodes of parkinsonian MS in 14 patients. A survey of health status preceding MS disclosed that deterioration of parkinsonian symptoms alone may induce MS, while association of major risk factors, i.e. rapid discontinuation of anti-parkinsonian drugs, dehydration or infection may precipitate or exacerbate MS. Cerebral vascular disorders, mechanical brain injury or physiological stress could be other risk factors leading to MS.

Brain SPECT with 123I-IMP for the early diagnosis of Creutzfeldt–Jakob disease

We performed brain CT and single-photon emission computed tomography (SPECT) using N-isopropyl-p-[123I] iodoamphetamine (123I-IMP) as a tracer in the early stage of seven patients with Creutzfeldt-Jakob disease (CJD). In four of the patients, we determined absolute values of regional cerebral blood flow (rCBF) in the frontal, temporal, parietal and occipital lobes, thalamus and cerebellum using an autoradiographic method with a single blood sample. Brain CT demonstrated no abnormal findings other than a mild age-related atrophy in all patients except for one patient with a low-density area in the left cerebellar hemisphere due to an old hemorrhage, whereas SPECT revealed a decreased uptake of the tracer in various parts of the cerebral cortex of all patients, sometimes in an asymmetrical pattern. Absolute values of rCBF showed a significant decrease in all examined regions of the patients as against healthy controls (P<0.0001). In three patients, SPECT demonstrated a decreased uptake throughout the cerebral cortex on visual inspection, whereas absolute values of rCBF revealed an obvious decrease of the uptake also in the thalamus and cerebellum. These results suggest that SPECT with quantification of rCBF using 123I-IMP might be a sensitive and useful technique not only for detecting a focal metabolic dysfunction but also for diagnosis in the early stage of CJD.

Muscle CT scan findings in McLeod syndrome and chorea-acanthocytosis

Computed tomography (CT) scans of lower leg muscles reveal a selective pattern of fat infiltration in the posterior compartment with spared gracilis, semitendinosus, and the lateral head of the gastrocnemius in both McLeod syndrome and chorea‐acanthocytosis, which are disorders characterized by the presence of circulating acanthocytes. The selectivity of affected muscles indicates that late onset and slowly progressive muscular atrophy in both diseases could be a consequence of primary myopathy. Asymmetrical muscle involvement may be seen during the process of degeneration only in McLeod syndrome, however, and may be helpful in distinguishing this disease from chorea‐acanthocytosis.

Distinctive features of degenerating Purkinje cells in spinocerebellar ataxia type 31.

Spinocerebellar ataxia type 31 (SCA31) is an autosomal dominant form of pure cerebellar ataxia that is caused by a disease‐specific insertion containing penta‐nucleotide repeats (TGGAA)n. Neuropathologically, cerebellar Purkinje cells are preferentially affected and reduced in number in SCA31, and they are often surrounded by halo‐like amorphous materials. In the present study, we performed neuropathological analyses on two SCA31 brains, and discussed the serial morphological changes of Purkinje cells in SCA31.We found that bent, elongated, often folded nuclei were observed frequently in degenerating Purkinje cells with the halo‐like structure. Conversely, Purkinje cells without this structure developed marked atrophy with severely slender and condensed nuclei. On the basis of these pathological findings, we propose two different processes for Purkinje cell degeneration in SCA31, namely, shrinkage of Purkinje cells with or without the halo‐like amorphous materials. The former, but not the latter, was considered to be specific to SCA31. Correspondingly, fragmentation of the Golgi apparatus was observed more frequently in Purkinje cells with the halo‐like structure than in those without this structure. We consider that the profound nuclear deformity and fragmentation of the Golgi apparatus are closely linked with the formation of the halo‐like structure in SCA31.

Multiple sclerosis with secondary syringomyelia. An autopsy report.

We report an elderly woman with multiple sclerosis who showed an extensive cavity formation in the midthoracic cord in addition to multiple abnormal intensity signals in the central nervous system on magnetic resonance imaging (MRI). The cavity decreased in size in response to corticosteroid therapy with an improvement in neurological symptoms. The autopsy demonstrated a slit-like cavity lined with no ependymal cells on the luminal surface in the lower cervical to midthoracic cord, with circumferentially distributed demyelinative lesions, leading to the pathological diagnosis of secondary syringomyelia. In this patient a limited necrosis formed in the spinal cord might have developed into a cavity formation with edematous fluid leading to subsequent episodes of neurological exacerbation.

Coexistence of hemidystonia and hemiballism in a diabetic patient with striatal hyperintensity on T1-weighted MRI

Sirs: Hemiballism or hemichorea associated with hyperglycemia and contralateral striatal hyperintensity on T1-weighted MRI has been recognized as a clinicoradiological syndrome. We report the case of an elderly diabetic patient showing hemidystonia as a manifestation of this disorder. A 76-year-old woman with a ten-year history of diabetes mellitus abruptly showed ballistic involuntary movement in the left upper and lower extremities, with fasting blood glucose at 264 mg/dl and glycosylated hemoglobin A1 c at 8.2 %; there was no ketonuria. Brain CT demonstrated a slight high-density area mainly in the posterior part of the right putamen (Fig. 1A), while MRI showed high intensity on T1-weighted images in the central and anterior part of the right lentiform nucleus and in the head of the right caudate nucleus (Fig. 1B, C). Two months later the patient complained of gait difficulties because of a dystonic posture involving shoulder overflexion, elbow extension, wrist and finger flexion, and knee extension on the left side when standing, in addition to mild ballistic movement. Surface electromyograms demonstrated tonic muscle activities in the left arm and repetitive bursts with regular intervals at a frequency of 0.5–1.5 Hz in the left upper and lower extremities in the supine position at rest (Fig. 2A). In the standing position, tonic muscle activities were increased in the left lower and upper extremities in association with dystonic posture (Fig. 2B). Brain CT and MRI demonstrated no new lesions beyond those found before the development of the dystonic posture. The choreoballistic movement and dystonic posture gradually improved without any anti-dopaminergic medication, and disappeared seven months and thirty months after the onset of disease, respectively. The abnormal lesions on CT and MRI gradually decreased and disappeared seven months after the onset of disease. The pathology of the striatum responsible for hyperintensity on T1-weighted MRI in this disorder remains unknown, but a vascular event is regarded as a possible cause of the striatal lesions based on the sudden onset and radiological features [1, 2]. Although hemorrhages, demyelination, calcium deposition or accumulations of unknown metabolites have been regarded as possible causes of the radiological changes [1, 2, 5, 7, 11, 14], examination of biopsy specimens have failed to demonstrate the corresponding pathological changes [11]. A peculiar feature in this patient is hemidystonia coexisting with hemiballism. Although the delayed onset of hemidystonia might have suggested another vasLETTER TO THE EDITORS