研究者詳細 - 田岡　俊昭

その他リンク： http://orcid.org/0000-0001-9227-0240

Displacement of the facial nerve course by vestibular schwannoma: preoperative visualization using diffusion tensor tractography. 国際誌 Open Access

Taoka T, Hirabayashi H, Nakagawa H, Sakamoto M, Myochin K, Hirohashi S, Iwasaki S, Sakaki T, Kichikawa K

Journal of magnetic resonance imaging : JMRI 24 巻 ( 5 ) 頁： 1005 - 10 2006年11月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Magnetic Resonance Imaging

Purpose: To preoperatively visualize the course of the facial nerve, which Is displaced by vestibular schwannoma, using diffusion tensor (DT) tractography, and to evaluate the agreement with surgical findings. Materials and Methods: The subjects were eight patients with vestibular schwannoma who had undergone removal surgery. DT MR images were obtained and tracts that were considered to represent the facial nerve were constructed. We assessed the success rate for tract construction and evaluated the agreement between tractography findings and surgery. Results: We obtained a tract that connected the internal auditory meatus and brainstem, and was considered to represent the facial nerve in seven of eight cases. The course of the constructed tract agreed with surgical findings in five of these seven cases. One exception was a case in which the tumor was too large to enable intraoperative observation of the facial nerve; however, the facial nerve appeared to be displaced anteriorly at intracapsular resection, in agreement with tractography. In the other case, the schwannoma was mostly cystic. Conclusion: Tractographs constructed using MR tensor images enabled us to identify tracts considered to represent facial nerves. We consider DT tractography to be a useful tool for preoperatively predicting facial nerve displacement in vestibular schwannoma. © 2006 Wiley-Liss, Inc.

DOI： 10.1002/jmri.20725

Global and region-specific analyses of apparent diffusion coefficient in dentatorubral-pallidoluysian atrophy.

Kin T, Hirano M, Taoka T, Furiya Y, Kataoka H, Kichikawa K, Ueno S

AJNR. American journal of neuroradiology 27 巻 ( 7 ) 頁： 1463 - 6 2006年8月

Global and region-specific analyses of apparent diffusion coefficient in dentatorubral-pallidoluysian atrophy 査読有り

T. Kin, M. Hirano, T. Taoka, Y. Furiya, H. Kataoka, K. Kichikawa, S. Ueno

AMERICAN JOURNAL OF NEURORADIOLOGY 27 巻 ( 7 ) 頁： 1463 - 1466 2006年8月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER SOC NEURORADIOLOGY

BACKGROUND AND PURPOSE: Dentatorubral-pallidoluysian atrophy (DRPLA) is an autosomal dominant spinocerebellar ataxia. Techniques for the quantitative assessment of neurodegenerative lesions remain to be established in this disease. We attempted to quantify global and region-specific neuro. degeneration in DRPLA using analysis of apparent diffusion coefficient (ADC) maps.
METHODS: Diffusion-weighted images (b = 1000 s/mm(2)) by echo-planar sequences were obtained with the use of a 1.5T clinical scanner. Whole-brain histogram and region of interest (ROI) analyses of ADC values as well as conventional MR imaging studies were performed in 6 patients with genetically confirmed DRPLA.
RESULTS: Histograms demonstrated significantly higher mean ADC values in the patients than in age- and sex-matched control subjects (P <.01). 1901 analysis revealed that the patients had significantly higher ADC values in the cerebellum and globus pallidus, preferentially affected regions (P <.05), but not in the thalamus, the region relatively spared in this disease. ADC values in the white matter were higher only in patients with adult-onset disease. Histogram analyses could more sensitively identify abnormalities than ROI analyses, because the former avoided errors associated with setting ROIs and thus had smaller P values on statistical analysis than the latter.
CONCLUSIONS: Histogram ADC analyses were more sensitive for the detection of neurodegeneration in DRPLA than ROI analyses, whereas ROI analyses revealed regional alterations reflecting the distribution of pathologic changes. Thus, histogram and ROI analyses complement each other and may permit the sensitive, quantitative evaluation of neurodegeneration in DRPLA, especially that involving the globus pallidus showing normal T2 signals.

Global and region-specific analyses of apparent diffusion coefficient in dentatorubral-pallidoluysian atrophy

Kin T., Hirano M., Taoka T., Furiya Y., Kataoka H., Kichikawa K., Ueno S.

American Journal of Neuroradiology 27 巻 ( 7 ) 頁： 1463 - 1466 2006年8月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：American Journal of Neuroradiology

BACKGROUND AND PURPOSE: Dentatorubral-pallidoluysian atrophy (DRPLA) is an autosomal dominant spinocerebellar ataxia. Techniques for the quantitative assessment of neurodegenerative lesions remain to be established in this disease. We attempted to quantify global and region-specific neurodegeneration in DRPLA using analysis of apparent diffusion coefficient (ADC) maps. METHODS: Diffusion-weighted images (b = 1000 s/mm2) by echo-planar sequences were obtained with the use of a 1.5T clinical scanner. Whole-brain histogram and region of interest (ROI) analyses of ADC values as well as conventional MR imaging studies were performed in 6 patients with genetically confirmed DRPLA. RESULTS: Histograms demonstrated significantly higher mean ADC values in the patients than in age-and sex-matched control subjects (P < .01). ROI analysis revealed that the patients had significantly higher ADC values in the cerebellum and globus pallidus, preferentially affected regions (P < .05), but not in the thalamus, the region relatively spared in this disease. ADC values in the white matter were higher only in patients with adult-onset disease. Histogram analyses could more sensitively identify abnormalities than ROI analyses, because the former avoided errors associated with setting ROIs and thus had smaller P values on statistical analysis than the latter. CONCLUSIONS: Histogram ADC analyses were more sensitive for the detection of neurodegeneration in DRPLA than ROI analyses, whereas ROI analyses revealed regional alterations reflecting the distribution of pathologic changes. Thus, histogram and ROI analyses complement each other and may permit the sensitive, quantitative evaluation of neurodegeneration in DRPLA, especially that involving the globus pallidus showing normal T2 signals.

Evaluation of arteriosclerotic changes in the intracranial carotid artery using the calcium score obtained on plain cranial computed tomography scan: Correlation with angiographic changes and clinical outcome. 国際誌

Taoka T, Iwasaki S, Nakagawa H, Sakamoto M, Fukusumi A, Takayama K, Wada T, Myochin K, Hirohashi S, Kichikawa K

Journal of computer assisted tomography 30 巻 ( 4 ) 頁： 624 - 8 2006年7月

White matter T2 hyperintensity development and clinical deterioration after status epilepticus in a patient with dentatorubral-pallidoluysian atrophy. 国際誌

Takamure M, Hirano M, Taoka T, Ueno S

Clinical neurology and neurosurgery 108 巻 ( 5 ) 頁： 482 - 5 2006年7月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Clinical Neurology and Neurosurgery

Serial T2-weighted magnetic resonance imaging in a 29-year-old woman with juvenile type dentatorubral-pallidoluysian atrophy (DRPLA) demonstrated that a cerebral white matter hyperintensity appeared within 2 months after status epilepticus and persisted for more than 20 months. The patient had rapidly progressive mental regression and became akinetic after status epilepticus. The chronological relationship between the signal changes and the clinical deterioration suggested that the epilepsy, at least in part, contributed to the progression of white matter degeneration, the hallmark of DRPLA. © 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.clineuro.2005.01.011

Serial therapy-induced changes in tumor shape in cervical cancer and their impact on assessing tumor volume and treatment response 査読有り

NA Mayr, WTC Yuh, T Taoka, JZ Wang, DH Wu, JF Montebello, SL Meeks, AC Paulino, VA Magnotta, M Adli, JI Sorosky, MV Knopp, JM Buatti

AMERICAN JOURNAL OF ROENTGENOLOGY 187 巻 ( 1 ) 頁： 65 - 72 2006年7月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER ROENTGEN RAY SOC

OBJECTIVE. The purpose of this study was to evaluate the patterns and distribution of tumor shape and its temporal change during radiation therapy (RT) in cervical cancer and the effect of tumor configuration changes on the correlation between region of interest (ROI)-based and diameter-based MRI tumor measurement.
MATERIALS AND METHODS. Serial MRI examinations (T1-weighted and T2-weighted images) were performed in 60 patients (age range, 29-75 years; mean, 53.3 years) with advanced cervical cancer (stages IB2-IVB/recurrent) who were treated with RT at four time points: start of RT, during RT (at 2-2.5 and at 4-5 weeks of RT), and post-RT. Tumor configuration was classified qualitatively into oval, lobulated, and complex based on MR film review. Two methods of tumor volume measurement were compared: ellipsoid computation of three orthogonal diameters (diameter based) and ROI volumetry by delineating the entire tumor volume on the MR workstation (ROI based). Temporal changes of tumor shape and the respective tumor volumes measured by the two methods were analyzed using linear regression analysis.
RESULTS. Most tumors (70%) had a non-oval (lobulated and complex) shape before RT and became increasingly irregular during and after RT 84% at 2-2.5 weeks of RT (p = 0.037), 86% (p = 0.025) at 4-5 weeks, and 96% post-RT (p = 0.010), compared with 70% pre-RT. Diameter-based and ROI-based measurement correlated well before RT (r = 0.89) but not during RT (r = 0.68 at 2-2.5 weeks, r = 0.67 at 4-5 weeks of RT).
CONCLUSION. Most cervical cancers are not oval in shape pretherapy, and they become increasingly irregular during and after therapy because of nonconcentric tumor shrinkage. ROI-based volumetry, which can optimally measure irregular volumes, may provide better response assessment during treatment than diameter-based measurement.

DOI： 10.2214/AJR.05.0039

Taoka T., Iwasaki S., Nakagawa H., Sakamoto M., Fukusumi A., Takayama K., Wada T., Myochin K., Hirohashi S., Kichikawa K.

Journal of Computer Assisted Tomography 30 巻 ( 4 ) 頁： 624 - 628 2006年7月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Computer Assisted Tomography

PURPOSE:: This study evaluated the correlation between quantified calcification of the carotid siphon and arteriosclerotic changes on angiography as well as clinical outcome. We used the calcium score obtained from intracranial carotid arteries viewed on plain CT. METHOD/MATERIALS:: We examined carotid siphons of 72 consecutive patients who had undergone both plain CT and angiography of the brain. We calculated calcium scores of the carotid siphon. Arteriosclerotic changes on angiography were categorized as "smooth," "irregular," or "stenosis." We assessed the correlation between the scores and arteriosclerotic changes both in the carotid siphon and the bifurcation. We reviewed clinical records approximately 2 years after examination and evaluated the scores of patients who did and did not experience cerebral strokes. RESULTS:: In the evaluation between angiographic findings of siphon and calcium score of the siphon, there were statistically significant differences between the "smooth" and "irregular", "irregular" and "stenosis" and the "smooth" and "stenosis". In the evaluation between angiographic findings of bifurcation and the score of the siphon, a statistically significant difference was only seen between "smooth" and "stenosis". No significant differences in calcium scores were observed between patients groups who did or did not experience a cerebral stroke. CONCLUSIONS:: There were a positive correlation between calcium scores on CT and angiographic changes of arteriosclerosis in the siphon as well as bifurcation, indicating angiographic changes can be predicted using calcium scores. However, the degree of calcification in the siphon cannot be used to predict the possibility of a future cerebral stroke. Copyright © 2006 by Lippincott Williams & Wilkins.

DOI： 10.1097/00004728-200607000-00012

Pituitary stalk compression by the dorsum sellae: possible cause for late childhood onset growth disorders. 国際誌

Taoka T, Iwasaki S, Okamoto S, Sakamoto M, Nakagawa H, Otake S, Fujioka M, Hirohashi S, Kichikawa K

Magnetic resonance imaging 24 巻 ( 5 ) 頁： 651 - 6 2006年6月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Magnetic Resonance Imaging

Purpose: The purpose of this study was to evaluate the relationship between pituitary stalk compression by the dorsum sellae and clinical or laboratory findings in short stature children. Materials and Methods: We retrospectively reviewed magnetic resonance images of the pituitary gland and pituitary stalk for 34 short stature children with growth hormone (GH) deficiency and 24 age-matched control cases. We evaluated the degree of pituitary stalk compression caused by the dorsum sellae. Body height, GH level, pituitary height and onset age of the short stature were statistically compared between cases of pituitary stalk compression with associated stalk deformity and cases without compression. Results: Compression of the pituitary stalk with associated stalk deformity was seen in nine cases within the short stature group. There were no cases observed in the control group. There were no significant differences found for body height, GH level and pituitary height between the cases of pituitary stalk compression with associated stalk deformity and cases without compression. However, a significant difference was seen in the onset age between cases with and without stalk compression. Conclusion: Pituitary stalk compression with stalk deformity caused by the dorsum sellae was significantly correlated with late childhood onset of short stature. © 2006 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.mri.2005.12.015

Diffusion anisotropy and diffusivity of white matter tracts within the temporal stem in Alzheimer disease: evaluation of the "tract of interest" by diffusion tensor tractography.

Taoka T, Iwasaki S, Sakamoto M, Nakagawa H, Fukusumi A, Myochin K, Hirohashi S, Hoshida T, Kichikawa K

AJNR. American journal of neuroradiology 27 巻 ( 5 ) 頁： 1040 - 5 2006年5月

Diffusion anisotropy and diffusivity of white matter tracts within the temporal stem in Alzheimer disease: Evaluation of the "tract of interest" by diffusion tensor tractography

Taoka T., Iwasaki S., Sakamoto M., Nakagawa H., Fukusumi A., Myochin K., Hirohashi S., Hoshida T., Kichikawa K.

American Journal of Neuroradiology 27 巻 ( 5 ) 頁： 1040 - 1045 2006年5月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：American Journal of Neuroradiology

PURPOSE: Our aim was to determine whether diffusion anisotropy and diffusivity of white matter tracts of the temporal stem in patients with Alzheimer (AD) can be evaluated independently by using diffusion tensor tractography. MATERIALS AND METHODS: Subjects included 15 patients with AD (11 women and 4 men; mean age, 74 years) and 15 age-matched control subjects (11 women and 4 men; mean age, 72 years). Diffusion tensor images were acquired by using echo-planar imaging. We drew tractographies of the uncinate fasciculus, inferior occipitofrontal fasciculus, and Meyer's loop, with diffusion tensor analysis software. We measured diffusion anisotropy, diffusivity, and the number of voxels along the "tracts of interest" and used the Student t test to compare results between patients with AD and controls. RESULTS: Values of diffusion anisotropy of the bilateral uncinate fasciculus and left inferior occipitofrontal fasciculus were significantly lower for patients with AD than for controls. Also, values of diffusivity in the bilateral uncinate fasciculus were significantly greater for patients with AD than for controls. There was no significant difference in diffusion anisotropy or diffusivity along Meyer's loop between the 2 groups. There was no significant difference in the number of voxels included in all constructed tracts between patients with AD and controls. CONCLUSION: White matter tracts of the temporal stem can be evaluated independently by using diffusion tensor tractography, which appears to be a promising technique for determining changes in white matter in degenerative diseases.

Diffusion tensor imaging in cases with visual field defect after anterior temporal lobectomy

Apparent diffusion coefficient in dentatorubral-pallidoluysian atrophy 査読有り

Tesseki Kin, Makito Hirano, Toshiaki Taoka, Hiroshi Kataoka, Foshiko Furiya, Hirohide Asai, Kimihiko Kichikawa, Satoshi Ueno

ANNALS OF NEUROLOGY 60 巻頁： S53 - S53 2006年

Taoka T., Sakamoto M., Iwasaki S., Nakagawa H., Fukusumi A., Hirohashi S., Taoka K., Kichikawa K., Hoshida T., Sakaki T.

American Journal of Neuroradiology 26 巻 ( 4 ) 頁： 797 - 803 2005年12月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：American Journal of Neuroradiology

BACKGROUND AND PURPOSE: Visual defect due to optic radiation injury is a complication of temporal lobectomy for temporal epilepsy. To investigate whether diffusion tensor imaging can delineate the changes in optic radiations after lobectomy, we evaluated parameters on tensor images for optic radiations and correlated them with visual defect. METHODS: We examined 14 cases after temporal lobectomy. Durations after surgeries ranged from 3 weeks to 9 years. The cases were classified into three groups on the basis of the severity of visual field defect (A-C, with group C the most severe). We evaluated signals on T2-weighted images and parameters of tensor images, including fractional anisotropy (FA) and apparent diffusion coefficient (ADC), for the optic radiation in both the operated and intact side. RESULTS: On T2-weighted images, high signals in optic radiations were seen in four cases, occurring more than 4 weeks after surgery. The mean operated-to-intact side FA ratio in the optic radiation decreased according to severity of visual defect (group A, 0.88; group B, 0.89; group C, 0.73). The mean operated-to-intact side ADC ratio showed no significant difference in the overall cases. The ratio for ADC, however, tended to increase according to visual defect in cases after 10 weeks postsurgery. CONCLUSION: Optic radiation showed a decreased FA value in cases after temporal lobectomy. In later stages, ADC values tended to increase and high signal intensities on T2-weighted images were observed. The FA value can be used for evaluating Wallerian degeneration of optic radiation even in the early stages after surgery. © American Society of Neuroradiology.

Proton MR spectroscopy of adult-onset dentatorubral-pallidoluysian atrophy Open Access

Kin T., Hirano M., Taoka T., Takamure M., Furiya Y., Kichikawa K., Ueno S.

Magnetic Resonance in Medical Sciences 4 巻 ( 3 ) 頁： 123 - 127 2005年12月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Magnetic Resonance in Medical Sciences

Purpose: To quantify impairment of the basal ganglia (globus pallidus and thalamus) in adult-onset dentatorubral-pallidoluysian atrophy (DRPLA). Methods: Five patients with genetically definite adult-onset DRPLA (aged 51 to 65 years, mean 55.6 years) and 5 age- and sex-matched healthy controls underwent conventional magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy (MRS) of the brain in the voxels predominantly containing the globus pallidus or the thalamus. Results: Conventional MRI studies showed apparently normal intensities in the globus pallidus and thalamus. MRS showed that the choline (Cho)/creatine (Cr) ratio for the patients' globus pallidus, the region preferentially affected in DRPLA, was significantly higher than that in the controls (p<0.05). The N-acetylaspartate (NAA)/Cr ratio for the globus pallidus and the Cho/Cr and NAA/Cr ratios for the thalamus, the region relatively spared in this disease, did not differ significantly between the patients and controls. Conclusions: MRS may sensitively and specifically detect biochemical alterations in susceptible regions of patients with adult-onset DRPLA.

DOI： 10.2463/mrms.4.123

Open Access