Hereditary spastic paraplegia with thin corpus callosum and cataract: a clinical description of two siblings

We report two siblings with autosomal recessive hereditary spastic paraplegia and thin corpus callosum. These patients had a similar history of progressive spastic gait, followed by mental impairment in the second decade. In addition to rigospasticity, ataxia, and foot deformity, both patients had congenital cataract on ophthalmologic examination. The association of cataract and thin corpus callosum suggests a distinct genetic disorder involving these structures in complicated spastic paraplegia.

Truncal and limb apraxia in corticobasal degeneration

We report a patient with probable corticobasal degeneration with prominent truncal apraxia, and review the literature.

Postencephalitic pure anomic aphasia: 2-year follow-up

We report a patient with pure anomic aphasia following encephalitis. Brain magnetic resonance imaging (MRI) revealed bilateral temporal lesions, and subsequent focal atrophy in the left anterior inferior temporal lobe. Over the course of a 2-year follow-up, the patient's naming difficulty persisted without other dysfunction of language or memory. These observations indicate a contribution of the left anterior inferior temporal region to object naming.

Comparison of brain perfusion in corticobasal degeneration and Alzheimer's disease

To compare brain perfusion between corticobasal degeneration (CBD) and Alzheimer's disease (AD), we measured regional cerebral blood flow (rCBF) semiquantitatively with single-photon emission computed tomography in 10 patients with CBD and 16 with AD. There was no significant difference in age or illness duration between the patients with CBD and AD. Mini-Mental State Examination scores were significantly lower in the AD patients than in the CBD patients. All CBD patients showed asymmetric akinetic-rigid syndrome and limb apraxia. Four CBD patients were demented, and 1 AD patient had parkinsonism. Compared with 12 age-matched control subjects, the average of the left and right rCBF values for the CBD patients was significantly reduced in the prefrontal, anterior cingulate (AC), medial premotor, sensorimotor (SM), posterior parietal (PP) and superior temporal (ST) cortices as well as in the basal ganglia (BG) and thalamus (Th), while the prefrontal, PP and ST cortices were significantly hypoperfused in the AD patients. In the CBD patients, rCBF was significantly less in the AC and SM cortices, and in the Th and BG, and significantly greater in the PP cortex than in the AD patients. Interhemispheric differences of rCBF in the inferior prefrontal and SM cortices were significantly greater in the CBD patients than the AD patients. It is concluded that rCBF comparison may aid in differentiating CBD from AD.

[Neuropsychological comparison between corticobasal degeneration and progressive supranuclear palsy]

We conducted a neuropsychological comparison among cases with corticobasal degeneration (CBD; n = 8), those with progressive supranuclear palsy (PSP; n = 5) and healthy control subjects (n = 12) using an extensive neuropsychological battery assessing memory and executive functions. There were no significant differences among three groups for age, education, scores on the Mini-Mental State Examination and Zung's self-rating depression scale. Both patient groups showed retrieval impairment without recognition difficulties, and a dysexecutive syndrome. Along with those similarities, we observed some differences between CBD and PSP patients. Memory impairments in CBD patients were more marked than PSP patients in Rey's complex figure test, while they were less prominent in Rey's auditory verbal learning test. Perseverative errors of Nelson in Wisconsin card sorting test (Keio version) were more marked in CBD patients than in PSP patients. These two diseases showed memory and executive dysfunctions probably due to subcortico-frontal dysfunction. Some neuropsychological differences may help to distinguish CBD clinically from PSP.

Cerebral blood flow correlates of higher brain dysfunctions in corticobasal degeneration

To investigate clinicoanatomic correlations of higher brain dysfunctions in corticobasal degeneration, regional cerebral blood flow (rCBF) was semiquantitatively measured with single-photon emission computed tomography in 9 patients with corticobasal degeneration and 12 age-matched control subjects. The patients showed significant reductions of relative tracer uptake in widespread cortical areas, as well as the basal ganglia and thalamus. Interhemispheric difference of hypoperfusion was significant in the sensorimotor and posterior parietal cortices. Asymmetric limb apraxia and cortical sensory disturbance corresponded to either sensorimotor cortical or posterior parietal cortical hypoperfusion or both. Compared with the patients without dementia, those with dementia showed significant reductions of relative rCBF in the inferior prefrontal region in the more affected hemisphere. The unique correlation of cortical signs with regional hypoperfusion may be useful in distinguishing between corticobasal degeneration and other neurodegenerative diseases.

Cerebral blood flow in corticobasal degeneration and progressive supranuclear palsy

To compare brain perfusion between corticobasal degeneration (CBD) and progressive supranuclear palsy (PSP), we investigated regional cerebral blood flow (rCBF) semiquantitatively with single-photon emission computed tomography and [123I]iodoamphetamine in six patients with CBD and five with PSP. Compared with 12 age-matched control subjects, the average of the left and right rCBF values for the CBD patients was significantly reduced in the inferior prefrontal, anterior cingulate, medial premotor, sensorimotor, posterior parietal, and superior temporal cortices as well as in the basal ganglia and thalamus, whereas only the medial premotor cortex was significantly hypoperfused in the PSP patients. Compared with the PSP patients, the CBD patients showed significantly decreased rCBF in the inferior prefrontal, sensorimotor, and posterior parietal cortices, but not in the subcortical regions. Compared with the controls, interhemispheric differences of rCBF were significant in the inferior prefrontal, sensorimotor, and posterior parietal cortices of the CBD patients but in only the medial prefrontal cortex of the PSP patients. These results indicate that rCBF reductions are more extensive and asymmetric in CBD than in PSP, although the two diseases share medial frontal involvement.

Corneomandibular reflex in ALS

To clarify the diagnostic value of corneomandibular reflex (CMR) in ALS, the authors examined the prevalence of CMR and other pathologic reflexes in 42 patients with ALS and 110 patients with stroke. A total of 30 of 42 ALS patients had positive CMR. Compared with the patients with hemiparesis or pseudobulbar palsy after stroke, the ALS patients showed a significantly higher frequency of CMR but no other pathologic reflexes. CMR is a sensitive indicator of upper motor neuron involvement in ALS.

Pure anomic aphasia caused by a subcortical hemorrhage in the left temporo-parieto-occipital lobe

There have been few case reports of pure anomic aphasia and the underlying mechanism remains to be clarified. We report a patient in whom pure anomic aphasia was caused by subcortical hemorrhage in the left temporo-parieto-occipital lobe. Based on magnetic resonance images and cerebral blood flow imaging, the structural lesion underlying the pure anomic aphasia was thought to be located at the left temporo-occipital junction.

Cerebral blood flow in pure dysarthria: role of frontal cortical hypoperfusion

BACKGROUND AND PURPOSE

Isolated dysarthria, termed pure dysarthria, develops rarely after stroke, and its pathophysiology remains unclear. To clarify the underlying mechanism of pure dysarthria, we investigated lesion sites and cerebral blood flow in patients with pure dysarthria.

METHODS

We examined 12 patients with pure dysarthria who underwent MRI and cerebral blood flow study. To visualize cortical blood flow, a three-dimensional display was generated from single-photon emission computed tomography (SPECT). Regional cerebral blood flow of the patients was semiquantitatively measured with SPECT and N-isopropyl-p[123I]iodoamphetamine as a tracer and compared with that of 11 control subjects.

RESULTS

On MRI, multiple lacunar infarctions were noted bilaterally in 11 patients, all of whom had lesions involving the internal capsule or corona radiata. The other patient had a unilateral internal capsule-corona radiata infarction. Three-dimensional display showed frontal cortical hypoperfusion in 8 patients. Since interhemispheric differences of blood flow were not significant in any region of the 12 patients, the mean of left and right cortical blood flow was analyzed. Compared with the control subjects, cortical perfusion was significantly reduced in the patients' frontal regions, sparing the sensorimotor, temporal, and parietal cortices and the cerebellum. Reductions of perfusion were rather pronounced in the anterior opercular, medial prefrontal and premotor, and anterior cingulate regions.

CONCLUSIONS

Pure dysarthria results mainly from multiple lacunar infarctions, which induce frontal cortical hypoperfusion, probably due to interruption of corticosubcortical networks. We conclude that frontal cortical hypoperfusion, particularly in the anterior opercular and medial frontal regions, plays an important role in the development of pure dysarthria.

Asymmetric changes in somatosensory evoked potentials correlate with limb apraxia in corticobasal degeneration

To clarify the underlying mechanism of limb apraxia in corticobasal degeneration (CBD), we investigated somatosensory evoked potentials in 5 patients with CBD, as compared with 12 age-matched control subjects. All patients presented with asymmetric limb apraxia, particularly of limb-kinetic type. N20 latencies were significantly prolonged following median nerve stimulation on the more apraxic side, but not on the less apraxic side. These results suggest that limb apraxia in CBD may, at least in part, be due to a disorder of somatosensory information processing involving the parietal cortex.

Electrophysiological comparison between corticobasal degeneration and progressive supranuclear palsy

Multimodal evoked potentials were recorded in four patients with corticobasal degeneration (CBD), four patients with progressive supranuclear palsy (PSP) and 15 normal control subjects. CBD and PSP patients showed significant prolongation of the N200 and P300 latencies of auditory event-related potentials compared with controls. Patients with CBD showed significant prolongation of interpeak latencies between N13 and N20 of short-latency somatosensory evoked potentials compared with the controls and patients with PSP. The present results show that the two diseases have different electrophysiologic features.

Parkinsonism after acute cadmium poisoning

A 64-year-old man suffered from acute exposure to cadmium, followed by multiple organ failure. Three months after exposure, the patient developed parkinsonian features. The case suggests that cadmium intoxication may damage the basal ganglia, resulting in parkinsonism.

Early morphological changes in the thalamocortical projection onto the parietal cortex following ablation of the motor cortex in the cat

Following a previous report that the cerebellar-induced cerebral response in the parietal cortex changes acutely after ablation of the frontal motor cortex, the present experiments tested whether morphological changes of the thalamo-parietal projection occur after ablation of the motor cortex. Anterograde and retrograde tracing with wheat germ agglutinin conjugated with horseradish peroxidase was used in intact and lesioned cats. The thalamocortical projection was labeled anterogradely by tracer injection into the thalamic ventral anterior and ventral lateral (VA-VL) nuclear complex that mainly relays the cerebello-cerebral projection, and thalamic neurons were labeled retrogradely by injection of the tracer into the parietal cortex. The labeled terminals in the parietal cortex of the intact animals were distributed densely in layer I and sparsely in layers III-IV, whereas those of the lesioned animals were distributed densely in layers I and III-IV. The distribution of the retrogradely labeled neurons after multiple tracer injections in layers III-IV of the parietal cortex was different in the intact and lesioned cats. In the intact animals, the labeled neurons were distributed sparsely in the central lateral nucleus and in the lateral posterior and pulvinar nuclear complex. In contrast, after ablation of the frontal cortex, the labeled neurons were also observed in the VA-VL nuclear complex. These differences between the intact and lesioned animals were detectable within 48 h after the lesion.

Motor neuron disease following generalized fasciculations and cramps

We report a case of motor neuron disease in which fasciculations and cramps progressed generally before the development of muscle wasting. After involvement of the upper and lower motor neurons became clinically manifest, widespread fasciculations and cramps persisted and accompanied pseudotetany. The present case suggests that spinal cord pathology of motor neuron disease can cause the abnormal excitability of the motor neurons, resulting in the development of generalized fasciculations and cramps.

Transient worsening of Parkinson's disease after cigarette smoking

We report a patient with probable Parkinson's disease who experienced a temporary worsening of his symptoms and signs after cigarette smoking. Deterioration of tremor, rigidity, and writing disturbance began soon after the inhalation of cigarette smoke and persisted for 15 minutes. Chewing nicotine gum also induced a brief worsening of the patient's symptoms. Aggravation of parkinsonian symptoms after cigarette smoking appeared to be caused by nicotine alone, although the mechanism for this effect remains unclear.

[A case of allergic granulomatous angitis with beneficial effects of plasma exchange]

A 54-year-old man had suffered from bronchial asthma, followed by numbness and muscle weakness of the extremities. He was admitted to our department in July, 1994, because of progression of the symptoms. On admission, neurological examination revealed muscle weakness with atrophy and sensory disturbance of multiple mononeuritic type. Blood tests revealed eosinophilia and an increase in rheumatoid factor, IgE levels and P-ANCA. A sural nerve biopsy showed necrotizing vasculitis and inflammation with eosinophil infiltration. The patient was diagnosed as having allergic granulomatous angitis,and treated with steroid pulse therapy without beneficial effect. Plasma exchange was performed twice, which resulted in remarkable improvement in motor and sensory disturbance. The present case suggests that plasma exchange has beneficial effects on severe cases with allergic granulomatous angitis.

Mitochondrial encephalomyopathy with elderly onset of stroke-like episodes

A 52-year-old woman with a history of a hearing disturbance since age 20 experienced visual hallucinations and convulsions, followed by right hemiparesis and aphasia. On the basis of a muscle biopsy and mitochondrial DNA analysis, she was diagnosed as mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS). This case is unique in that the stroke-like episodes occurred 30 years after disease onset.

Visual form agnosia in multiple sclerosis

We report a case of multiple sclerosis with visual form agnosia and callosal syndromes. Initially, the patient's visual recognition of object form was severely disturbed at the perceptual stage, in association with left-sided ideomotor apraxia and agraphia. Magnetic resonance imaging showed large white matter lesions in the bilateral frontal and occipital lobes, the latter extending to the occipitotemporal junction, and widespread corpus callosum lesions. Over the course of one year follow-up, neuropsychological examinations indicated that the patient's visual recognition defects occurred not only at the early substage of form perception, but also at the stage of reproducing the shape of objects from visual memory store. The present case suggests that neural connections between the striate cortex and occipitotemporal visual areas are crucial for both the perceptual and associative stages of visual object recognition.

Visual and somatosensory evoked potentials in Parkinson's and Binswanger's disease

To compare subcortical involvement of Parkinson's disease (PD) with that of Binswanger's disease (BD), we examined visual evoked potentials (VEPs) and somatosensory evoked potentials (SEPs) in 29 patients with PD and 7 patients with BD and 11 control subjects. The patients with PD were divided into two groups: PD without dementia (nD-PD: n = 18) and PD with dementia (D-PD: n = 11). The D-PD patients showed significantly longer P100 latencies in VEPs compared with the nD-PD patients or controls. The P100 latencies were negatively correlated with Mini-Mental State Examination (MMSE) score in the PD patients. The BD patients showed significantly longer central conduction time (CCT) in SEPs (interpeak latency between N13 and N20 responses) compared with the nD-PD patients or controls. There was no correlation between CCT and MMSE score in the BD patients. These results suggest that PD has a predilection for sensory system involvement distinct from that of BD. In D-PD, the visual system seems more vulnerable than the somatosensory system, but almost the reverse is true of BD.

Multimodal evoked potentials in Alzheimer's disease and Binswanger's disease

Somatosensory evoked potentials (SEPs), brainstem auditory evoked potentials (BAEPs), visual evoked potentials (VEPs), and auditory event-related potentials (ERPs) were studied in 15 patients with Alzheimer's disease (AD), eight patients with Binswanger's disease (BD), and 15 normal subjects. Patients with BD showed significant prolongation of the interpeak latency between N13 and N20 (N13-N20) and N20-P40 of SEPs as compared with the normal controls, whereas patients with AD only demonstrated significant prolongation of N20-P40. The interpeak latency between waves I and V of BAEPs in patients with both AD and BD was significantly longer than that of controls. There were no significant differences in P100 latency of VEPs among these three groups. Both groups with dementia showed significant prolongation of N200 and P300 latencies of ERPs compared with normal controls. In addition, patients with AD showed significant prolongation of P200 latency. We conclude that these two dementing diseases have different electrophysiologic features that may be related to their underlying pathogenetic mechanisms. Furthermore, the measurement of multimodal evoked potentials may be helpful in the differential diagnosis of AD and BD.

Focal cortical hypoperfusion in corticobasal degeneration demonstrated by three-dimensional surface display with 123I-IMP: a possible cause of apraxia

To clarify cortical lesions responsible for apraxia in cortico-basal degeneration (CBD), we reconstructed three-dimensional surface images from single-photon emission computed tomography (SPECT) data with N-isopropyl-p[I-123]-iodoamphetamine in two patients with CBD. Both had limb-kinetic apraxia (LKA) and one also had constructional apraxia (CA). Both showed asymmetrical cortical hypoperfusion in the perirolandic area. The patient with CA had unilateral hypoperfusion in the posterior parietal area. Thus, cortical hypoperfusion in the perirolandic area corresponded to LKA, and that in the posterior parietal area to CA.

High thoracic neurinoma mimicking femoral neuralgia

We report a case of spinal neurinoma at a high thoracic level, whose main presentation was intractable pain in a body part innervated by the right femoral nerve. Sensations of pain and temperature were impaired in the right thigh, but usual symptoms of myelopathy were undetectable. In conjunction with the other reports, this case suggests that spinal tumors at high thoracic levels can produce remote symptoms mimicking peripheral neuropathy such as femoral or sciatic neuralgia.

The role of the left somatosensory cortex in human hand movement

Hemispheric dominance for motor control in the human brain is still unclear. Here we propose asymmetric sensorimotor integration during human hand movements. We investigated the dexterity of hand movements and related sensory functions in four right-handed patients with cerebrovascular lesions in the postcentral gyrus. To clarify the distributions of cortical damage, semiquantitative analysis of regional cerebral blood flow (rCBF) was performed using single photon emission computed tomography (SPECT), and a three-dimensional surface display was generated from SPECT. Scores on motor and sensory tasks and rCBF values in the patients were compared with those in control subjects. All patients presented with asymmetric clumsiness of complex finger movements, in association with impairments of combined sensations such as stereognosis. These findings were indicative of a disorder of sensory information processing necessary to guide the movements. Two patients with left hemispheric damage showed bilateral clumsy hands, predominating on the right side, while the other two patients with right hemispheric damage showed only a left clumsy hand. In agreement with asymmetric clumsiness, measurement of rCBF along with a three-dimensional surface display revealed cortical hypoperfused areas, mainly in the perirolandic cortices, comprising the primary motor and somatosensory cortices. Perirolandic cortical hypoperfusion was bilateral in the two patients with bilateral clumsy hands, but only on the right side in the other two patients with left clumsy hands. These results suggest a dominant role of the left somatosensory cortex in sensorimotor integration for complex finger movements of humans.

Visual evoked potentials (VEPs) in Parkinson's disease: correlation of pattern VEPs abnormality with dementia

There has been some debate about abnormalities in visual evoked potentials (VEP) in Parkinson's disease (PD). To elucidate the mechanism underlying abnormal VEPs, we investigated the relationship between pattern-reversal VEPs elicited by large checks and mental functions in PD patients (n = 32), as compared with VEPs of age-matched control subjects (n = 22). The PD patients were divided into two groups: PD without dementia (nD-PD; n = 21) and PD with dementia (D-PD; n = 11). All patients but five of the nD-PD patients were being treated with anti-parkinsonian drugs. The D-PD patients showed significantly prolonged P100 latencies compared with both the nD-PD patients and controls (p < 0.01 and p < 0.01, respectively). The PD patients treated with levodopa had significantly longer P100 latencies than the other PD patients. In PD patients, the P100 latency correlated significantly with illness duration (p < 0.05). There was also a significant negative correlation with P100 latency and Mini-Mental State Examination (MMSE) score (p < 0.05). The MMSE score did not correlate with illness duration in PD patients. These findings suggest that the VEPs abnormality elicited by large checks is related to dementia independent of progression of the illness, and that a nondopaminergic neurotransmitter system may play a role in the development of VEPs delay elicited by large checks.

The nature of apraxia in corticobasal degeneration

Images

[A case with clinical features of progressive supranuclear palsy with apraxia--corticobasal degeneration?]

We report a 65-year-old female who have suffered from progressive gait disturbance for 3 years, followed by disorientation and forgetfulness. Neurological examination revealed dementia, constructional disability, limb kinetic apraxia, supranuclear gaze palsy, especially on downward gaze, symmetrical muscle rigidity and bradykinesia. Involuntary movements were undetectable. Brain MRI showed significant brain atrophy in the left fronto-parietal lobe. The three-dimensional surface display with 131I-IMP demonstrated decreased cerebral blood flow in the left frontoparietal cortex. The diagnosis of this case is discussed with regard to either progressive supranuclear palsy or corticobasal degeneration or both.

Corticosteroid-responsive parkinsonism associated with primary Sjögren's syndrome

A 74-year-old woman with primary Sjögren's syndrome confirmed by salivary gland biopsy presented with parkinsonism. Magnetic resonance imaging (MRI) of the brain revealed multiple small high intensity lesions in the deep white matter, basal ganglia and pons on T2-weighted images. Treatment with L-dopa failed to improve the parkinsonian features. After the initiation of prednisolone 30 mg/day, the parkinsonian signs and symptoms significantly improved. Some lesions on MRI were decreased in size after corticosteroid therapy. These findings suggest that parkinsonism associated with primary Sjögren's syndrome is at least in part attributable to small vessel vasculopathy such as focal inflammation or edema.

Latex agglutination test negative cryptococcal meningitis in an immuno-competent individual: a case report

We report a case with progressive mental deterioration and persistent low grade fever, who was diagnosed to have cryptococcal meningitis. This case is unique in that the cryptococcal latex agglutination antigen test was consecutively negative. The diagnosis was made by sequential CSF culture.

Cerebral blood flow in subcortical global aphasia. Perisylvian cortical hypoperfusion as a crucial role

BACKGROUND AND PURPOSE

Global aphasia after subcortical stroke is very rare, and its pathophysiology remains unsolved. To clarify the mechanism underlying subcortical global aphasia, we investigated lesion sites and cerebral blood flow in patients with subcortical global aphasia and nonaphasic patients with subcortical stroke.

METHODS

We examined four patients with global aphasia and four nonaphasic patients. Language testing was performed more than 4 weeks after the onset. Measurement of cerebral blood flow was done between 35 and 75 days after stroke by using single-photon emission computed tomography (SPECT) with N-isopropyl-p[123I]iodoamphetamine as a tracer and three-dimensional surface display generated from SPECT.

RESULTS

All aphasic patients had subcortical lesions in the putamen, posterior internal capsule, temporal isthmus, and periventricular white matter in the left hemisphere. No cortical lesions were found on either magnetic resonance imaging or computed tomographic scanning. The nonaphasic patients had smaller periventricular white matter lesions and no temporal isthmus lesions. All aphasic patients showed cortical hypoperfusion mainly in the perisylvian areas, including Broca's and Wernicke's areas. In contrast, cortical cerebral blood flow of the nonaphasic patients was decreased in smaller areas and spared the perisylvian language areas.

CONCLUSIONS

These results suggest that cortical hypoperfusion in the perisylvian language areas, presumably due to undercutting of the white matter, is crucial for the development of subcortical global aphasia.

[Beneficial effect of steroid pulse therapy on Wernicke-Korsakoff syndrome due to hyperemesis gravidarum]

A 25-year-old woman suffered from hyperemesis gravidarum when she was seven weeks pregnant. Since her vomiting continued, she received intravenous dextrose and electrolytes without thiamine in a hospital. One month later, she developed gait disturbance, followed by confusion and dysarthria. On admission to our department, she was confusional and had ataxic dysarthria. Spontaneous and gaze evoked nystagmus was present. Limb coordination was bilaterally ataxic. Based on her clinical course and symptoms, she was diagnosed as having Wernicke's encephalopathy. From the admission day, intravenous infusion of vitamin B1 (600 mg/day) was started. A few days later, her consciousness and limb ataxia began to improve. However, truncal ataxia and polyneuropathy became evident. Eight weeks after onset, she developed Korsakoff's psychosis such as anterograde and retrograde amnesia, disorientation and confabulation. We administered large amounts of corticosteroid (methylprednisolone 500 mg/day) in order to reduce brain edema or stabilize the impaired blood-brain barrier. Soon after, her psychosis began to improve gradually. She recovered remarkably from the psychosis, but she was left with persistent nystagmus, mild ataxic gait and polyneuropathy. The present case suggests that corticosteroid may have the beneficial effect on Wernicke-Korsakoff syndrome.

Cerebello-thalamo-cerebral projection from the dentate nucleus onto the frontal eye field in the cat

To elucidate the role of the cerebellar dentate nucleus in oculomotor system, we investigated the dentato-cerebral projection onto the frontal cortex around the fundus of the presylvian sulcus corresponding to a subregion of the frontal eye field (FEF) in the cat. Stimulation of the dentate nucleus induced laminar field potentials consisting of mainly a surface positive-depth negative wave and a subsequent depth positive wave with or without a surface negative wave in the contralateral FEF. Thalamic relay neurones, identified by collision test, were mainly distributed in the dorsal part of the ventromedial (VM) nucleus. Injection of wheat germ agglutinin conjugated horseradish peroxidase into the thalamic VM nucleus anterogradely labelled afferent terminals in layers I and III of the FEF and retrogradely labelled somata of cerebello-thalamic neurones in the contralateral dentate nucleus. Both electrophysiological and morphological results consistently revealed cerebello-thalamo-cerebral projection onto the FEF which may be implicated in eye-limb coordination control.

Trigeminal sensory neuropathy with abnormal taste following acute sinusitis

We report a case of isolated trigeminal sensory neuropathy associated with impairment of taste sensation following acute sinusitis. Sensory disturbance was distributed mainly in the ophthalmic division, and partly in the maxillary and mandibular divisions. No other cranial nerves were involved. An otological procedure resulted in complete recovery. The unique combination of trigeminal neuropathy and abnormal taste seemed to be caused by the infectious process involving the gasserian ganglion of the trigeminal nerve.

Three-dimensional surface display using 123I-IMP in a case of motor neuron disease with dementia

A case of motor neuron disease with dementia is presented. A brain CT showed atrophic changes mainly in the left frontal cortex, and 123I-IMP SPECT disclosed a decrease in 123I-IMP uptake in the frontal regions. To distinguish a subregion related to dementia from that related to motor system disorders, a three-dimensional surface display with 123I-IMP was reconstructed. The imaging method clearly demonstrated cortical hypoperfusion in the inferomedial frontal cortex and the motor-sensory cortex. These findings suggest that dementia may be due to the former lesion and motor system disorders due to the latter lesion, respectively.

[Two cases of hepatic encephalopathy associated with a high-intensity area in the basal ganglia on T1-weighted MR images]

The authors report two cases of hepatic encephalopathy with chronic hepatic failure. Case 1 was a 78-year-old woman with liver cirrhosis, admitted because of general fatigue and loss of appetite. Her electroencephalogram showed frequent slow waves in the theta range with intermittent triphasic waves T1-weighted MR images showed increased signal intensity in the globus pallidus and the putamen. Case 2 was a 71-year-old woman with chronic hepatitis, admitted because of depression. Her electroencephalogram showed frequent slow wave activities in the theta-delta range with intermittent trisphasic waves. Her serum ammonia level was 84 micrograms/dl (normal 12-54 micrograms/dl). T1-weighted MR images showed increased signal intensity in the globus pallidus, the putamen and the hypothalamus. On the basis of these findings, both patients were diagnosed as having hepatic encephalopathy, although disturbance of consciousness was not obvious. The observed MR image abnormalities might be due to the metabolic and pathological changes of chronic hepatic failure. Such MRI findings may be useful for the diagnosis of hepatic encephalopathy.

[Event-related potential and visual evoked potential in patients with Parkinson's disease]

The event-related potential (ERP) and visual evoked potential (VEP) were recorded in 28 patients with Parkinson's disease (PD) and 28 normal subjects. Nine of the PD patients had dementia and 19 did not. Dementia was evaluated according to the criteria for dementia assigned by the DSM III-R, and mental faculties were estimated using the Mini-Mental State Examination (MMSE). ERP was recorded during auditory discriminative tasks. The latencies of N100, P200, N200 and P300 from the Pz region were measured. VEP was recorded during pattern reversal stimulation. The latency of P100 was measured for each eye stimulated. PD patients with dementia showed significant prolongation of the N200 and P300 latencies of ERP and of the P100 latency of VEP compared with the values in normal subjects and in PD patients without dementia. There was a significant correlation between the N200 latency of ERP and the P100 latency of VEP in PD patients with dementia. The findings indicate that the N200 and P300 latencies of ERP are related to cognitive information processing and also suggest that dysfunction in the central visual system plays a role in abnormal pattern VEP in patients with dementia. Furthermore, the disturbance of early sensory processing in response to visual stimuli may roughly parallel the impairment of cognitive information processing in terms of ERP in PD patients with dementia.

Slowly progressive limb-kinetic apraxia with a decrease in unilateral cerebral blood flow

We report two patients with slowly progressive motor disorders, whose principal manifestations were asymmetric limb-kinetic apraxia and muscle rigidity. In both patients MRI revealed no responsible lesion, whereas single photon emission computed tomography (SPECT) showed a decrease in cerebral blood flow (CBF) in the unilateral hemisphere. One patient with mainly right-sided apraxia had a decreased CBF in the left central region between the frontal and parietal cortices, and the other patient with left-sided apraxia in the right parietal cortex. In agreement with asymmetric clinical symptoms, the regional CBF decrease in the unilateral cortical areas including the frontal and parietal cortices may suggest a degenerative disease, presumably diagnosed as having cortico-basal degeneration.