Takeshi Wada

Nara Medical University, Kashihara, Nara, Japan

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Publications (38)39.54 Total impact

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    ABSTRACT: Hemorrhagic presentation of spinal epidural arteriovenous fistulas (AVFs) is rare in patients with cervical spinal vascular lesions. The present report describes a patient with cervical spine epidural AVFs associated with anterior spinal artery aneurysm at the same vertebral level presenting with subarachnoid hemorrhage. A 54-year-old man presented with sudden onset of headache. Computed tomography of the head showed subarachnoid hemorrhage. Diagnostic angiography revealed an epidural AVF located at the C1-2 level that was fed mainly by the dorsal somatic branches of the segmental arteries from the radicular artery and anterior spinal artery. This AVF drained only into the epidural veins without perimedullary venous reflux. Further, there was a 4-mm anterior spinal artery aneurysm in the vicinity of the fistula that was thought to be the cause of the hemorrhage. Endovascular transarterial fistulas embolization from the right radicular artery was performed to eliminate the AVF and to reduce hemodynamic stress on the aneurysm. No new symptoms developed after the treatment and discharged without neurological deficits. The aneurysm was noted to be reduced in size after the treatment and totally disappeared by 1 year later, according to follow-up angiography. Anterior spinal artery aneurysm from a separate vascular distribution may coexist with spinal epidural AVFs. In the setting of spinal subarachnoid hemorrhage, comprehensive imaging is indicated to rule out such lesions.
    Journal of stroke and cerebrovascular diseases: the official journal of National Stroke Association 10/2014;
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    ABSTRACT: The objective of this study was to determine long-term outcomes after stent placement for subclavian artery (SA) obstructive lesions assisted by intraoperative intravascular ultrasound (IVUS). The study included 25 lesions in 24 patients who underwent stent placement assisted by intraoperative IVUS for subclavian artery stenosis or obstruction at our hospital between January 2003 and August 2010. Outcome was evaluated based on the results within 30 postoperative days (technical success rate, improvement in upper extremity ischemia, steal syndrome, left-right blood pressure difference, and perioperative complications) and the results after 30 postoperative days (incidence of vertebrobasilar artery territory infarction and restenosis). Stent placement and vessel dilatation were successful in all patients, without perioperative complications. Upper extremity ischemia, steal syndrome, and left-right blood pressure difference disappeared in all cases. During follow-up observation (6-96 months; median 51 months), no restenosis occurred at the stent placement site in any patient. In one case, four years after initial treatment, stenosis was noted proximal to the stent placement site. Satisfactory long-term as well as short-term outcomes were achieved after stent placement for SA obstructive lesions assisted by intraoperative IVUS evaluation.
    The neuroradiology journal. 04/2014; 27(2):213-21.
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    ABSTRACT: Intracranial giant vertebral artery aneurysms are extremely rare in the pediatric population and are associated with significant morbidity and mortality. The present report describes a case of a pediatric patient with giant vertebral artery aneurysm who presented with intracranial mass effect. This patient was successfully treated with endovascular parent artery occlusion and coil embolization.
    Surgical Neurology International 01/2014; 5(Suppl 4):S143-7. · 1.18 Impact Factor
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    ABSTRACT: Periprocedural ischemic stroke is one problem associated with carotid artery stenting (CAS). This study was designed to assess whether preoperative statin therapy reduces the risk of periprocedural ischemic complications with CAS. In this prospective study at 11 centers, patients with carotid artery stenosis (symptomatic ≥50 %, asymptomatic ≥80 %) and a high risk of carotid endarterectomy but without previous statin treatments were divided into two groups by low-density lipoprotein cholesterol (LDL-C) levels. With LDL-C ≥120 mg/dl, the pitavastatin-treated (PS) group received pitavastatin at 4 mg/day. With LDL-C <120 mg/dl, the non-PS group received no statin therapy. After 4 weeks, both groups underwent CAS. Frequencies of new ipsilateral ischemic lesions on diffusion-weighted imaging within 72 h after CAS and cerebrovascular events (transient ischemic attack, stroke, or death) within 30 days were assessed. Among the 80 patients enrolled, 61 patients (PS group, n = 31; non-PS group, n = 30) fulfilled the inclusion criteria. New ipsilateral ischemic lesions were identified in 8 of 31 patients (25.8 %) in the PS group and 16 of 30 patients (53.3 %) in the non-PS group (P = 0.028). Cerebrovascular events occurred in 0 patients in the PS group and in 3 of 30 patients (10.0 %) in the non-PS group (P = 0.071). Multivariate analyses demonstrated the pitavastatin treatment (β = 0.74, 95 % confidence interval 0.070-1.48, P = 0.042) to be an independent factor for decreasing post-CAS ischemic lesions. Pretreatment with pitavastatin significantly reduced the frequency of periprocedural ischemic complications with CAS.
    CardioVascular and Interventional Radiology 12/2013; · 2.09 Impact Factor
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    ABSTRACT: PURPOSE Diffusion kurtosis is a statistical measure for quantifying the deviation of the water diffusion profile from a Gaussian distribution. The current study acessed the time course of diffusion kurtosis and evaluated the period of pseudo-normalization after cerebral infarctions. METHOD AND MATERIALS Subjects included 25 cases / 30 lesions of cerebral infarction. The duration between onset and imaging ranged from 1 day to 122 days. Diffusion kurtosis measurements were done with b values of 0, 1000, and 2000 sec/mm2 applied in 30 directions. Diffusion kurtosis images are generated, including axial kurtosis (Kax) and radial kurtosis (Krad) to the eigenvector. We also acquired T2 weighted image (T2WI), diffusion weighted image (DWI) and apparent diffusion coefficient (ADC) images. The time course of the relative values for T2WI, DWI, ADC, Krad, and Kax were evaluated and the period for pseudo-normalization was obtained. RESULTS The trend curve of relative Krad indicates that there was a trend for relative Krad to decrease according to the duration after infarction onset, and that lesions from 10 days to 2 weeks after infarction onset showed lower Krad values compared with the contralateral side. The trend curve of the relative Kax showed high values in cases within 10 days to 2 weeks after infarction onset. There was also a trend for relative Kax to decrease according to the duration after infarction onset, which represented the pseudo-normalization period. The days for pseudo-normalization were 45days, 21days, 14 days and 25 days for DWI, ADC, Krad and Kax respectively. CONCLUSION Diffusion kurtosis values showed increases in lesions early after infarction and showed decreases earlier than DWI. Krad showed pseudo-normalization earlier than that of ADC, and the pseudo-normalization of Kax was a little later than that of ADC. Because DKI can show different time courses after the onset of infarction compared with DWI or ADC, additional information for white matter tissue with infarction can be provided using this imaging technique. Specifically, information by DKI including Kax and Krad seems helpful in making detailed evaluation for the duration after onset of infarction in combination with T2WI, DWI and ADC. CLINICAL RELEVANCE/APPLICATION Since DKI can show different time courses, information by DKI including Kax and Krad seems helpful in making detailed evaluation for the duration after onset of infarction in addition to T2WI, DWI and
    Radiological Society of North America 2013 Scientific Assembly and Annual Meeting; 12/2013
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    ABSTRACT: Optimal platelet inhibition is an important therapeutic adjunct in patients with carotid artery stenosis undergoing carotid artery stenting (CAS). Clopidogrel resistance is associated with increased periprocedural thromboembolic complications from neurovascular stent placement procedures. The addition of cilostazol to dual antiplatelet therapy (DAT) has been reported to reduce platelet reactivity and to improve clinical outcomes after percutaneous coronary intervention. This study was undertaken to evaluate the impact of adjunctive cilostazol in patients with CAS. Platelet function was assessed by light transmittance aggregometry using the VerifyNow assay. Sixty-four consecutive patients who underwent CAS received standard DAT, clopidogrel (75 mg daily), and aspirin (100 mg daily) more than 4 weeks before the procedure. From 2010 to 2011 (period I), 28 patients underwent CAS under standard DAT. From 2011 to 2013 (period II), 36 patients prospectively had preoperative assessment of platelet function, and 13 patients with clopidogrel resistance received adjunctive cilostazol (200 mg daily) in addition to standard DAT. The incidence of new ipsilateral ischemic lesions on diffusion-weighted imaging a day after CAS and ischemic or hemorrhagic events within 30 days was assessed. Clopidogrel resistance was indentified in 12 patients (43%) in period I and 13 patients (36%) in period II (P = .615). In period II, the addition of cilostazol significantly decreased P2Y12 reaction units and % inhibition (P = .006 and P = .005, respectively), and there was a significant difference in P2Y12 reaction units between the two periods. New ipsilateral ischemic lesions were significantly decreased in period II (2/36 patients) compared with period I (7/28 patients; P = .034); however, there was no significant difference in hemorrhagic and thromboembolic events between the two periods. Adjunctive cilostazol (triple antiplatelet therapy) in clopidogrel-resistant patients reduces the rate of clopidogrel resistance and suppresses new ischemic lesions without hemorrhagic complications, as compared with standard DAT. Antiplatelet management based on the evaluation of antiplatelet resistance would be required for prevention of perioperative thromboembolic complications in CAS.
    Journal of vascular surgery: official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter 11/2013; · 3.52 Impact Factor
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    ABSTRACT: The present study aimed to identify the types of curved lesions that are difficult to place Carotid Wallstent (CWS). The study targeted 31 consecutive carotid artery (CA) stenosis underwent carotid artery stenting using CWS. CWS placement success rate, stenosis location, lesion tortuosity, and relationship with stent placement failures were investigated. Lesion tortuosity was defined as the angle formed by 2 tangential lines between internal CA and common CA from the inflection point (IP) was defined as the center of lesion curvature. Stenosed lesions were classified into type A or B. Type A was defined as if the distal end of the stenosis was located proximal to the IP at a distance ≥0.5 of a vertebral body based on the posterior height of the 3rd vertebral body, otherwise was type B. The stent placement success rate was 93.5% (29/31). The 2 unsuccessfully stented lesions, both lesions were significantly different from other lesions by having a lesion tortuosity less than 90° and by belonging to type B. Since CWS placement is difficult in patients with CA stenosis located close to the IP at a lesion tortuosity ≤90°, open-cell stents should be considered as an alternative.
    SpringerPlus 01/2013; 2:468.
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    ABSTRACT: PURPOSE In contrast enhanced (CE) CT in head and neck (HN) region, swelling of pharyngeal wall is sometimes observed after contrast agent (CA) administration compared to plain (P) CT (Figure). We made retrospective evaluation of clinical cases in order to assess the frequency and the relevance to anaphylactic reaction of the pharyngeal wall swelling. METHOD AND MATERIALS The subjects were 463 HN CE-CT (285 males and 178 females, average age 63.1) and 119 3D-CT angiography (CTA) examinations (93 males and 26 females, average age 71.3). In CE-CT, 100ml of 300mgI/ml CA was intravenously administrated with 1.0ml/sec, and 80ml of 370mgI/ml CA and 25ml of saline was administrated with 4.0ml/sec in 3D-CTA,. We defined the posterior hypopharyngeal wall as the reference region because the morphological change of the region was least in the volunteer scan. Two radiologists evaluated the CT images with agreement for the posterior hypopharyngeal wall swelling. The hypopharyngeal wall thickness (WT) was measured on CE and plain CT in the cases suspected the wall swelling and increase ratio {(WTCE - WTP) / WTP * 100} was calculated. The ratio over 30% was defined as significant wall swelling. The clinical information including anaphylactic reaction after CT was investigated. RESULTS Hypopharyngeal wall swelling was visually suspected in 41 cases (8.7%) in CE-CT and 16 (13.4%) in 3D-CTA and the significant hypopharyngeal wall swelling was found in 4 cases (0.9%) in CE-CT and 7 (5.9%) in 3D-CTA. The frequency of the hypopharyngeal wall swelling was significantly more in 3D-CTA than CE-CT by the Chi square test. No clinical symptom indicating the anaphylactic reaction was found in any cases during and after the CT examination. CONCLUSION The frequency of the hypopharyngeal wall swelling after the CA administration was higher in 3D-CTA than HN CE-CT, so the high blood concentration of CA was suspected to be related to the occurrence of the phenomenon. Although the hypopharyngeal wall swelling was suspected to be connected with the anaphylactic reaction, the finding was subclinical change in our evaluation. The symptomatic wall swelling related to anaphylactic reaction was supposed to have more severe morphological change and lower frequency. CLINICAL RELEVANCE/APPLICATION It should be known that the swelling of pharyngeal wall is sometimes observed in contrast enhanced CT in head and neck region but not always indicates an anaphylactic reaction.
    Radiological Society of North America 2012 Scientific Assembly and Annual Meeting; 11/2012
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    ABSTRACT: PURPOSE We examined the signal intensities of structures in the newborn brain on T1 weighted image (T1WI) and evaluate correlation between the signal intensities and the postnatal age or the gestational age at the examination. METHOD AND MATERIALS We evaluated the T1WI of consecutive 79 newborns who showed normal development after two years follow up. The gestational age ranged from 35 weeks 3 days to 46 weeks 6 days, and the postnatal age ranged from 8 days to 119 days. We performed qualitative grading for signal intensities of the structures including vermis, dentate nuclei, subthalamic nuclei, globus pallidus, fornix, splenium, pyramidal tracts in the precentral gyri, corona radiata, and internal capsule. Grading of the signal intensities on T1WI were as follows; Grade 1: higher than the cortex and close to the signal of fat, Grade 2: higher than the cortex, Grade 3: between the cortex and the surrounding structures, and Grade 4: indistinguishable from the surrounding structures. We correlated the signal grades with their gestational age and with the postnatal age at examination by using Kruskal-Wallis test. RESULTS There were statistically significant (p<0.01) positive correlations found between signal intensity and the gestational age at examination in the pyramidal tracts in the precentral gyri, corona radiata and internal capsule. In contrast, there were statistically significant (p<0.01) negative correlations found between signal intensity and the gestational age at examination in the cerebellar vermis, subthalamic nuclei, globus pallidus and fornix. CONCLUSION Maturation of the brain according to gestational age is associated with shortening of T1 relaxation time which is thought to be largely the result of myelination. The positive correlation between the gestational age and the signal of pyramidal tracts in the current study also support the effect of myelination. However, there were some structures which do not shows positive correlation to the gestational age but shows negative correlation to the postnatal age. Mechanism other than myelination may play role for the signal changes of the newborn brain in the structures such as subthalamic nuclei. CLINICAL RELEVANCE/APPLICATION On the T1WI of the newborn brain, there are structures showing high signal shortly after the birth such as subthalamic nucleus. It is important to know these structures for image interpretation.
    Radiological Society of North America 2012 Scientific Assembly and Annual Meeting; 11/2012
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    ABSTRACT: PURPOSE Diffusion kurtosis is a dimensionless statistical measure to quantifying the deviation of the water diffusion profile from Gaussian distribution. The purpose of the current study is to evaluate the changes in diffusion kurtosis in the cases with early cerebral infarction. METHOD AND MATERIALS The subjects of this study consist of the 15 cases with cerebral infarction. The duration between the onset and the imaging ranged from 3 hours to 5 weeks. Diffusion kurtosis image were acquired by using 3.0T clinical scanner (Siemens Magnetom Verio). An echo-planar diffusion weighted imaging sequence was used to acquire the diffusion kurtosis imaging data with b values of 1000 and 2000 sec/mm2 applied in distributed 30 directions. Diffusion kurtosis images are generated on the console of the imager (Siemens, work in progress), including axial (parallel) kurtosis to the eigenvector (Kax images) and radial kurtosis to the eigenvector (Krad images). We also evaluated diffusion weighted trace images (Dtrace images) generated from the same set of images. RESULTS In the population of the current study, there were 8 lesions of cerebral infarction within one week. In which, all 8 lesions showed high signal on Kax images, 3 lesion showed high signal on Krad images and all 8 lesions showed high signal on Dtrace images. Among the 5 lesions between one to 3 weeks, 2 lesions showed high signal on Kax images, no lesion showed high signal on Krad images and 5 lesions showed high signal on Dtrace images. Two lesions after 4 weeks of onset did not show high signal on three images. CONCLUSION Diffusion kurtosis value which is axial to the eigenvector showed increase in the lesions of the early infarction and showed earlier decrease compared to the diffusion weighted images. The results suggest large alteration in the intra-axonal diffusivity in the tissue of early infarction. Additional information for the tissue with very early infarction will be provided by diffusion kurtosis imaging. CLINICAL RELEVANCE/APPLICATION In the cases with early infarction, findings by diffusion kurtosis images made different behavior from the diffusivity. Additional information for the early infarction will be provided by this method.
    Radiological Society of North America 2012 Scientific Assembly and Annual Meeting; 11/2012
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    ABSTRACT: PURPOSE/AIM Movement disorder in elderly population is caused by various conditions. Neurodegenerative disease is one of the major causes among them. The purpose of this exhibit is to describe the role of imaging in the diagnosis of movement disorders and to illustrate this role with case-based presentations. CONTENT ORGANIZATION 1. Overview 2. Classification by the symptoms a) Parkinsonism and extra-pyramidal symptoms b) Involuntary movement c) Ataxia d) Motor weakness. 3. Classification by the causing substances a) Tauopathy b) Synucleinopathy c) TDP-43 proteinopathy 4. Role of imaging. Conventional and advanced techniques a) Conventional MRI b) MRS c) Diffusion imaging d) Susceptibility weighted imaging 5. Case-based presentations MSAs, SCAs, ALS etc. 6. Conclusion SUMMARY The diagnosis of movement disorders is a clinical challenge both for neurologist and neuroradiolgist. Conventional neuroimages still plays an important role in the diagnosis and management of these groups of entities as well as advanced images.
    Radiological Society of North America 2012 Scientific Assembly and Annual Meeting; 11/2012
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    ABSTRACT: BACKGROUND:: Retrograde leptomeningeal venous drainage (RLVD) in dural arteriovenous fistulas (DAVFs) is associated with intracerebral hemorrhage and nonhemorrhagic neurological deficits or death. Angiographic evidence of RLVD is a definite indication for treatment, but less-invasive methods of identifying RLVD are required. OBJECTIVE:: To evaluate the efficacy of susceptibility-weighted magnetic resonance imaging (SWI) in detecting RLVD in DAVFs. METHODS:: We retrospectively identified 17 DAVF patients who had angiographic evidence of RLVD and received treatment. Conventional angiography and SWI were assessed at pre- and post-treatment time points. The presence of RLVD on SWI was defined as cortical venous hyperintensity, and the presence of venous congestion on SWI venograms was defined as increased caliber of cortical or medullary veins. RESULTS:: Cortical venous hyperintensity was identified in pre-treatment SWI of 15 patients. Cortical venous hyperintensity was absent in early post-treatment SWI, consistent with the absence of RLVD in post-treatment angiography, in all but one of these patients. In two patients, cortical venous hyperintensity was identified during follow-up, indicating recurrence of RLVD. Cortical venous hyperintensity was not identified in pre-treatment SWI of two patients, despite angiographic evidence of RLVD. Venous congestion was identified in pre-treatment SWI venograms of 11 patients, and was of similar appearance to that identified from angiography. Venous congestive signs improved over the follow-up period. CONCLUSION:: The presence of SWI hyperintensity within the venous structure could be a useful indicator of RLVD in DAVF patients. SWI offers a noninvasive alternative to angiography for identification of RLVD in pre- and post-treated DAVF patients.
    Neurosurgery 10/2012; · 2.53 Impact Factor
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    ABSTRACT: INTRODUCTION: The presence of adhesions between the brain and the meningioma is an important factor that determines the success of total surgical removal. Brain surface motion imaging enables assessment of the dynamics of brain surface motion. A subtraction image of pulse-gated heavily T2-weighted images in different phases of the cardiac cycle provides a stripe pattern on the surface of the pulsating brain. Thus, the lack of a stripe pattern on the surface of extraaxial tumor indicates the presence of tumor-brain adhesion. The purpose of the present experiment was to evaluate the accuracy of predicting tumor-brain adhesion using the original double acquisition method and the improved single acquisition method. METHODS: The subjects were 67 meningioma cases patients who were surgically treated after brain surface motion imaging. Thirty-three cases were evaluated using the double acquisition method and 34 cases were evaluated with the single acquisition method. In the double acquisition method, the two sets of images are acquired as two independent scans, and in the single acquisition method, the images are acquired serially as a single scan. RESULTS: The findings for the double acquisition method agreed with the surgical findings in 23 cases (69.7 %), while findings from the single acquisition method agreed with the surgical findings in 26 cases (76.5 %). CONCLUSION: Pre-surgical evaluation for tumor-brain adhesion by brain surface motion imaging provides helpful information for meningioma surgery, especially when using the single acquisition method.
    Neuroradiology 06/2012; · 2.70 Impact Factor
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    ABSTRACT: INTRODUCTION: The current study evaluated the signal characteristics of susceptibility weighted imaging (SWI) of arteriovenous malformation (AVM), especially for draining veins. For this purpose, we identified the draining veins of the AVM on angiography and evaluated the signal on magnitude image for SWI (SWI-mag) and minimum intensity projection image (SWI-minIP). METHODS: Subjects were 14 cases with angiographically proven AVM. SWI-mag, SWI-minIP, and time-of-flight (TOF) magnetic resonance angiography were acquired. For the draining veins of the AVM identified on angiography, we analyzed signal intensity on the images listed above, and classified it into hyperintensity (hyper), mixed intensity (mixed), hypointensity (hypo), and no visualization. RESULTS: On the analysis of 27 angiographically proven draining veins, 19 draining veins were classified as hyper, 3 as mixed, 0 as hypo, and 6 as no visualization on SWI-mag. On TOF images, 21 draining veins were classified as hyper, 2 as mixed, 0 as hypo, and 4 as no visualization, while 6 draining veins did not show hyperintensity on TOF, and SWI-mag visualized 3 of these 6 veins as hyper. CONCLUSION: SWI-mag depicted most draining veins of AVM as hyperintensity. We speculate that this is mainly due to the higher concentration of oxygenated hemoglobin (oxy-Hb) and inflow effect of the draining vein. SWI-mag seems to be useful in the analysis and follow-up for AVM as the signal on the image may reflect physiological status.
    Neuroradiology 05/2012; · 2.70 Impact Factor
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    ABSTRACT: Intravascular treatment of cavernous dural arteriovenous fistula (dAVF) is usually safe and effective. However, we describe a patient with a rare brainstem hemorrhage during transvenous embolization (TVE). A 79-year-old woman suffered from left chemosis and diplopia. Cerebral angiography revealed a left cavernous dAVF with cortical venous drainage. The patient underwent TVE of the cavernous sinus (CS) via the left inferior petrosal sinus. Superior petrosal sinus (SPS) outflow occlusion was performed to avoid venous congestion, followed by superficial middle cerebral vein outflow occlusion, selective shunt occlusion of the middle meningeal artery, and superior orbital vein outflow occlusion. The patient's condition suddenly deteriorated during CS packing. A CT scan revealed a massive brainstem hemorrhage. Cerebral angiography did not show SPS reopening or redistributed drainage to the posterior fossa. Thus, TVE for cavernous dAVF can result in life-threatening vascular complications. Well-planned treatment strategies could avert this rare complication.
    Journal of Clinical Neuroscience 04/2012; 19(4):589-92. · 1.25 Impact Factor
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    ABSTRACT: We hypothesized that the pattern of branching of the lenticulostriate arteries (LSAs) is involved in the variation of the distribution of the infarction within the LSA region. Our purpose was to evaluate the visibility of LSAs in 3D time-of-flight (TOF) MR angiography (MRA) with a 3.0 T scanner and to investigate the branching patterns of LSAs. We performed 3D TOF MRA at 3.0 T for 100 healthy subjects. We assessed the number of LSAs and the number of branches arising from each LSA by evaluating MRA source images. In 200 hemispheres, 330 LSAs were visualized (mean = 1.65/hemisphere). In 3.5% of all hemispheres, no LSA was depicted; one LSA was depicted in 39%, two in 46.5%, and three in 11%. The maximum number of depicted LSA branches was five in 2% of all subjects, four in 7%, three in 26%, and two in 49% (mean = 2.3/subject). A large LSA trunk with three or more branches was found in 35% of subjects. Visualization of LSAs was possible in 96.5% of subjects by use of 3.0 T MRA. LSA branching patterns were variable, and a large LSA trunk with three or more branches was common.
    Japanese journal of radiology 02/2012; 30(4):331-5. · 0.73 Impact Factor
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    ABSTRACT: PURPOSE Brain surface motion image enables assessment of the dynamics of brain surface motion. A subtraction image of pulse gated heavily T2 weighted images of different phases of cardiac cycle provides stripe pattern on the surface of the pulsating brain. Thus, lack of stripe pattern on the surface of extraaxial tumor means tumor-brain adhesion. We compared double acquisition method and single acquisition method for brain surface motion image, and evaluated the accuracy for tumor-brain adhesion in meningioma cases. METHOD AND MATERIALS The subjects were 35 meningioma cases who were surgically treated after pre-surgical evaluation by brain surface motion imaging. Imaging consists of two sets of pulse-gated 3D fast spin echo scan with variable flip angle. In double acquisition method, the two sets of images acquired as two independent scan, and in single acquisition method, the images acquired serially as single scan. In both methods, images of systolic and diastolic phase were obtained, and subtraction was made. The double acquisition method was applied to 18 cases, and the single acquisition method was applied to 17 cases. We analyzed the presence of stripe pattern surrounding meningioma and judged degree of tumor-brain adhesion as “total (Figure; lower column)”, “partial” and “no (Figure; upper column)”, and correlated with the degree of adhesion on surgical findings. RESULTS The findings of double acquisition method agreed with surgical findings in 14 cases (77.8%), including 5 “total”, 6 “partial” and 3 “no” adhesion. While, the findings of single acquisition method agreed with surgical findings in 14 cases (82.4%), including 4 “total”, 3 “partial” and 7 “no” adhesion. CONCLUSION Prediction for brain/meningioma adhesion by brain surface motion imaging agreed with surgical findings in 77.8 to 82.4% of the cases, and the single acquisition methods provided presurgical information of higher accuracy about tumor-brain adhesion for meningioma. Pre-surgical evaluation for tumor-brain adhesion by brain surface motion image will provide helpful information in meningioma surgery. CLINICAL RELEVANCE/APPLICATION Brain surface motion image enables assessment of the dynamics of brain surface motion, and pre-surgical evaluation for tumor-brain adhesion by this image will provide helpful information in meningioma
    Radiological Society of North America 2011 Scientific Assembly and Annual Meeting; 12/2011
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    ABSTRACT: PURPOSE The purpose of this study is to investigate the morphological change of superior cerebellar peduncle (SCP) and middle cerebellar peduncle (MCP) in spinocerebellar degeneration (SCD) cases by observing “quarter notes” on the coronal image. The “quarter notes” stand for the shape of SCP and MCP on coronal images at the base of the fourth ventricle. We also made diffusion tensor analysis for evaluating the degree of degeneration in the MCP. METHOD AND MATERIALS We examined 19 cases of SCD cases and 24 controls. We measured SCP angle (angle between bilateral SCP on coronal plane at level of middle point of the base and top of fourth ventricle: Figure) by observing “quarter notes”. We also measured sectional area of MCP on coronal plane and thickness of MCP on axial plane. We obtained diffusion tensor images and measured apparent diffusion coefficient (ADC) and fractional anisotropy (FA) along MCP. We assessed the relationship among SCP angle, sectional area, thickness, ADC and FA of MCP. We also compared them between SCD cases and controls. RESULTS There was statistically significant correlation between SCP angle and sectional area of MCP on coronal plane. The SCP angle showed statistically significant correlation to ADC and FA of MCP. There was no statistically significant correlation between thickness of MCP on axial plane and ADC or FA of MCP. There were statistically significant decrease in sectional area of MCP and FA of MCP in SCD group, and statistically significant increase ADC of MCP in SCD group. The SCP angle showed statistically significant larger value in SCD group than controls. CONCLUSION The larger SCP angle tended to be seen in the case with more severe degeneration of MCP. The SCP angle by observing “quarter notes” on coronal plane may be a simple and convenient index to evaluate the degree of degeneration of MCP. CLINICAL RELEVANCE/APPLICATION In the clinical practice, the SCP angle by observing “quarter notes” may be a simple and convenient index to evaluate the degree of degeneration of MCP in SCD cases.
    Radiological Society of North America 2011 Scientific Assembly and Annual Meeting; 11/2011
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    ABSTRACT: Hemifacial spasm is usually caused by compression of the facial nerve at the root exit zone (REZ), whereas fusiform aneurysmal compression is extremely rare. The authors describe symptomatic hemifacial spasm caused by a contralateral fusiform aneurysm of the vertebral artery (VA) that was treated by endovascular coil embolization. A 55-year-old woman developed left hemifacial spasm that had gradually worsened over a period of 2 years before admission to our hospital. Cerebral angiography showed an elongated right VA fusiform aneurysm near the VA union that inclined toward the left side. The cause of the facial spasm was considered to be compression of the left facial nerve REZ by the aneurysm. Endovascular parent artery embolization including the aneurysm was performed. The hemifacial spasm disappeared within 3 months. Hemifacial spasm caused by contralateral VA fusiform aneurysm can be treated by intravascular parent artery occlusion with coil embolization.
    Neurosurgery 09/2011; 69(3):E768-71; discussion E771-2. · 2.53 Impact Factor
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    ABSTRACT: The Carotid WALLSTENT (CWS) and Filter-Wire EZ (FWEZ) embolic protection devices for use in carotid arterial stenting (CAS) were newly approved for national health insurance coverage in Japan in April 2010. This article describes our initial experience of CAS using the CWS and FWEZ. A group of 14 patients (12 men, 2 women; mean age 70.1 years, range 59-83 years) with 15 carotid artery stenoses at high risk for carotid endarterectomy were treated by CAS using the CWS and FWEZ. Of these stenoses, 5 were symptomatic with ≥50% stenosis of the common or internal carotid artery (ICA), and 10 were asymptomatic with ≥80% stenosis. The rates of technical success, ICA flow impairment during filter protection, periprocedural ischemic stroke, 30-day major adverse events (MAEs) (stroke, death, myocardial infarction), and development of new ischemic lesions on diffusion-weighted imaging (DWI) were assessed. CAS was successful in all cases. There was no ICA flow impairment, periprocedural ischemic stroke, or MAEs. DWI showed new ipsilateral ischemic lesions in only one patient (6.7%). Our initial clinical experience using the CWS and FEWZ for CAS was generally excellent, and the incidence of postprocedural ischemic lesions was low.
    Japanese journal of radiology 01/2011; 29(1):51-8. · 0.73 Impact Factor

Publication Stats

87 Citations
39.54 Total Impact Points

Institutions

  • 2001–2014
    • Nara Medical University
      • • Department of Radiology
      • • Department of Neurosurgery
      Kashihara, Nara, Japan
  • 2007–2011
    • Numazu City Hospital
      Sizuoka, Shizuoka, Japan