Endoscopic evaluation of food bolus formation and its relationship with the number of chewing cycles.

It is known that solid food is transported to the pharynx actively in parallel to it being crushed by chewing and mixed with saliva in the oral cavity. Therefore, food bolus formation should be considered to take place from the oral cavity to the pharynx. In previous studies, the chewed food was evaluated after the food had been removed from the oral cavity. However, it has been pointed out that spitting food out of the oral cavity interferes with natural food bolus formation. Therefore, we observed food boluses immediately before swallowing using an endoscope to establish a method to evaluate the food bolus-forming function, and simultaneously performed endoscopic evaluation of food bolus formation and its relationship with the number of chewing cycles. The subject was inserted the endoscope nasally and instructed to eat two coloured samples of boiled rice simultaneously in two ingestion conditions ('as usual' and 'chewing well'). The condition of the food bolus was graded into three categories for each item of grinding, mixing and aggregation and scored 2, 1 and 0. The score of aggregation was high under both ingestion conditions. The scores of grinding and mixing tended to be higher in subjects with a high number of chewing cycles, and the score of aggregation was high regardless of the number of chewing cycles. It was suggested that food has to be aggregated, even though the number of chewing cycles is low and the food is not ground or mixed for a food bolus to reach the swallowing threshold.

Cognitive impairments in multiple system atrophy: MSA-C vs MSA-P.

OBJECTIVE: We evaluated comprehensive neuropsychological tests and regional brain blood flow to compare cognitive dysfunction between two types of multiple system atrophy: predominant cerebellar ataxia (MSA-C) and predominant parkinsonism (MSA-P). METHODS: Twenty-one patients with MSA-C, 14 patients with MSA-P, and 21 age- and education-matched control subjects were subjected to neuropsychological tests and SPECT. The neuropsychological tests examined general cognition, verbal and visual memory, working memory, visuospatial and constructional ability, language, executive function, depression, and anxiety, while SPECT analysis examined brain perfusion. RESULTS: Patients with MSA-P showed severe involvement of visuospatial and constructional function, verbal fluency, and executive function compared with control subjects. Patients with MSA-C showed involvement only in visuospatial and constructional function compared with control subjects and a milder degree of involvement compared with patients with MSA-P. Patients with MSA-P tended toward a wide and severe impairment in cognitive function compared with patients with MSA-C. In addition, neuropsychological impairment in patients with MSA-P was significantly correlated with a decrease in prefrontal perfusion. This significant relation was not correlated to other factors such as age, education, and severity of cerebellar ataxia and parkinsonism, which are relevant factors associated with cognitive performance. CONCLUSIONS: Patients with multiple system atrophy-parkinsonism show more severe and more widespread cognitive dysfunctions than patients with multiple system atrophy-cerebellar ataxia. Our results also indicate that cognitive dysfunction in patients with multiple system atrophy-parkinsonism may be associated with prefrontal involvement.

Imaging of endolymphatic and perilymphatic fluid at 3T after intratympanic administration of gadolinium-diethylene-triamine pentaacetic acid.

By optimizing the inversion time of a 3D inversion-recovery turbo spin-echo sequence at 3T, we obtained separate images of endolymphatic and perilymphatic space 24 hours after intratympanic administration of gadolinium contrast material. In patients with Ménière disease, endolymphatic hydrops were detected not only in the cochlea but also in the vestibule. Fusion of the 2 types of images visualized the entire fluid space of the labyrinth and the spatial relationship of the 2 spaces.

Cognitive impairment in spinocerebellar ataxia type 6.

OBJECTIVE: The aim of this study was to evaluate cognitive impairment in patients with spinocerebellar ataxia type 6 (SCA6) and to verify the role of cerebellar involvement in intellectual abilities. METHODS: Cognitive function was examined in 18 patients with genetically confirmed SCA6 and in 21 age and education matched controls using a test battery for attention, verbal and visuospatial memory, as well as executive function. RESULTS: Verbal fluency and immediate visual memory task were markedly impaired in SCA6 compared with the control group (p = 0.007, 0.004 and 0.014, respectively). The results of the Rule Shift Cards Test was reduced in patients with SCA6, but the reduction was not significant. These cognitive dysfunctions did not correlated with CAG repeat length, age at onset, ataxic motor dysfunctional scale or depression. CONCLUSIONS: Our results demonstrate that specific cognitive deficits occur in patients with SCA6, independent of ataxic motor dysfunction. These deficits may reflect disruption of cortico-cerebellar circuits.

Clinical characteristics of synchronous colorectal cancer are different according to tumour location.

AIMS: The purpose of this study was to investigate the clinical characteristics of synchronous cancer patients, with particular attention given to variations in tumour location. METHODS: A retrospective evaluation of 249 synchronous cancer cases out of 3061 consecutive colorectal cancer patients. RESULTS: Multivariate analysis of risk factors for synchronous cancer according to tumour location revealed that male gender was a significant risk for synchronous lesions in the left colon only (odds ratio=2.05, 95% confidence interval 1.34-3.13). Meanwhile, aging was a risk factor for synchronous cancer in the right colon only (odds ratio=1.05, 95% confidence interval 1.02-1.08), and in both sides of the colon (odds ratio=1.03, 95% confidence interval 1.01-1.05), but not in the left colon only (odds ratio=0.98, 95% confidence interval 0.97-1.00). In addition, patients with synchronous lesions in the right colon only tended to have adenomas in the right colon, while those with synchronous lesions in the left colon only tended to have adenomas in the left colon (each P value <0.05). CONCLUSION: The risk factors and status of concurrent adenomas of synchronous cancer cases varied according to tumour location, suggesting that the colonic site susceptible to neoplasia varies according to patient characteristics.

Transient encephalopathy with reversible white matter lesions in children.

We report on two children with acute encephalopathy showing mild clinical manifestations and reversible white matter lesions. In both patients, MRI revealed high intensities on T (2)-weighted imaging and marked reductions of water diffusion in the white matter of the bilateral centrum semiovale and the corpus callosum. These abnormalities disappeared along with the neurological symptoms within a week in both patients. These children represent a characteristic group of patients among childhood acute encephalopathy.

Parry-Romberg syndrome with a clinically silent white matter lesion.

We performed a detailed neuroimaging study in a patient with Parry-Romberg syndrome. Proton MR spectroscopy demonstrated normal spectral patterns, though conventional MR imaging revealed high-intensity areas in the entire white matter in the left hemisphere. Single-photon emission tomography showed increased perfusion in the cortex of the affected hemisphere. Pyramidal tracts and optic radiations were preserved on diffusion tensor tractography. We will correlate these neuroimaging findings with normal psychomotor development in our patient.

Thyroid lesions and dioxin accumulation in the livers of jungle crows (Corvus macrorhynchos) in urban and suburban Tokyo.

Wild jungle crows (Corvus macrorhynchos) captured from three different areas of Tokyo were examined to evaluate environmental contamination of dioxins. In addition to the pathologic examination of their whole body, accumulation of dioxins, mRNA expression of the aryl hydrocarbon receptor (AhR), and pentoxyresorufin-O-depenthylase (PROD) activity in the liver were determined. Marked histopathologic changes were observed in the thyroid glands, especially in the crows from the urban downtown area. Levels of dioxins and their toxic equivalents (TEQs) and AhR mRNA expression in the livers of the crows from the urban area were higher than those from the suburban area. There was a high correlation between the levels of TEQs and PROD activity. The results of the present study demonstrated that jungle crows possess AhR-mediated toxicologic pathways similar to those of mammals and suggest the possibility that the thyroidal changes observed in the adult crows from the urban areas are one of the toxic manifestations resulting from exposure to dioxins and other environmental chemicals.

Primary lateral sclerosis presenting parkinsonian symptoms without nigrostriatal involvement.

We encountered three patients with primary lateral sclerosis (PLS) showing bradykinesia, frozen gait, and severe postural instability, as well as slowly progressive spinobulbar spasticity. Cranial magnetic resonance (MR) imaging showed precentral gyrus atrophy. Central motor conduction was markedly prolonged or failed to evoke a response. Positron emission tomography (PET) showed significant reduction of [18F]fluoro-2-deoxy-D-glucose uptake in the area of the precentral gyrus extending to the prefrontal, medial frontal, and cingulate areas. No abnormalities were seen in the nigrostriatal system with PET using [18F]fluorodopa or [11C]raclopride or with proton MR spectroscopy. Thus, widespread prefrontal, medial, and cingulate frontal lobe involvement can be associated with the parkinsonian symptoms in PLS.

Multiple regional 1H-MR spectroscopy in multiple system atrophy: NAA/Cr reduction in pontine base as a valuable diagnostic marker.

OBJECTIVE: We performed (1)H-MR spectroscopy ((1)H-MRS) on multiple brain regions to determine the metabolite pattern and diagnostic utility of (1)H-MRS in multiple system atrophy (MSA). METHODS: Examining single voxels at 3.0 T, we studied metabolic findings of the putamen, pontine base, and cerebral white matter in 24 MSA patients (predominant cerebellar ataxia (MSA-C), n = 13), parkinsonism (MSA-P), n = 11), in 11 age and duration matched Parkinson's disease patients (PD) and in 18 age matched control subjects. RESULTS: The N-acetylaspartate to creatine ratio (NAA/Cr) in MSA patients showed a significant reduction in the pontine base (p<0.0001) and putamen (p = 0.02) compared with controls. NAA/Cr in cerebral white matter also tended to decline in long standing cases. NAA/Cr reduction in the pontine base was prominent in both MSA-P (p<0.0001) and MSA-C (p<0.0001), and putaminal NAA/Cr reduction was significant in MSA-P (p = 0.009). It was also significant in patients who were in an early phase of their disease, and in those who showed no ataxic symptoms or parkinsonism, or did not show any MRI abnormality of the "hot cross bun" sign or hyperintense putaminal rims. NAA/Cr in MSA-P patients was significantly reduced in the pontine base (p = 0.001) and putamen (p = 0.002) compared with PD patients. The combined (1)H-MRS in the putamen and pontine base served to distinguish patients with MSA-P from PD more clearly. CONCLUSIONS: (1)H-MRS showed widespread neuronal and axonal involvement in MSA. The NAA/Cr reduction in the pontine base proved highly informative in the early diagnosis of MSA prior to MRI changes and even before any clinical manifestation of symptoms.

Contrast enhancement of the cochlear aqueduct in MR imaging: its frequency and clinical significance.

There have been no previous reports on contrast enhancement of the cochlear aqueduct in magnetic resonance imaging. The purpose of the present study was to evaluate the frequency and significance of this finding. Thirty-one patients (15 men and 16 women; age range 18-81 years) with otologic symptoms (sudden sensorineural hearing loss, vertigo, or tinnitus) were examined using contrast-enhanced imaging on a 1.5-T MR scanner. The normal ear served as the control. Two radiologists evaluated contrast enhancement in the area of the cochlear aqueduct. Forty-eight of 62 ears (77.4%) showed contrast enhancement of the cochlear aqueduct, but no significant differences in the frequency of contrast enhancement were observed between patients with and patients without vertigo, tinnitus, sensorineural hearing loss, cerebellopontine angle tumors, or a high-riding jugular bulb. In addition, no gender- or age-related differences were noted. Contrast enhancement of the cochlear aqueduct was frequently observed, but the frequency of enhancement in symptomatic ears was not significantly higher than in control ears. The results of this study may prove helpful in avoiding unnecessary examinations and potential diagnostic confusion.