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Dive into the research topics where Kunihiko Fukuda is active.

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Featured researches published by Kunihiko Fukuda.


American Journal of Roentgenology | 2006

High-Spatial-Resolution MRI of Non-Masslike Breast Lesions: Interpretation Model Based on BI-RADS MRI Descriptors

Mitsuhiro Tozaki; Kunihiko Fukuda

OBJECTIVE The purpose of this study was to assess an interpretation model based on BI-RADS MRI descriptors and high-spatial-resolution MR images in lesions showing non-masslike enhancement. MATERIALS AND METHODS Retrospective review was performed of 30 consecutive lesions showing non-masslike enhancement. MRI was performed on a 1.5-T scanner using the volumetric interpolated breath-hold examination sequence. The distribution patterns were classified into three categories: single quadrant/solitary lesion (linear), single quadrant/grouped lesion (focal, regional, segmental), and multiquadrant lesion (multiple regions, diffuse). The presence of a ductal pattern was assessed in the enhancing lesions after the tumor distribution had been decided. In addition to the BI-RADS MRI descriptors, the presence of clustered ring enhancement was also assessed in heterogeneous enhancing lesions. RESULTS The most frequent morphologic finding among the benign lesions was a linear pattern (50%) followed by homogeneous internal enhancement (42%), whereas a segmental pattern (56%) (p = 0.003), heterogeneous internal enhancement (44%), and clustered ring enhancement (44%) (p = 0.01) were the most frequent findings in malignant lesions. The features with the highest positive predictive value for carcinoma were a segmental distribution (100%), a clustered ring enhancement (100%), and a clumped internal architecture (88%). Using this interpretation model, the positive predictive value for carcinoma was 94%. CONCLUSION A combination of BI-RADS MRI descriptors and clustered ring enhancement criteria is useful for the differential diagnosis of lesions showing non-masslike enhancement.


Cardiovascular Diabetology | 2007

Genetic association of glutathione peroxidase-1 with coronary artery calcification in type 2 diabetes: a case control study with multi-slice computed tomography

Masami Nemoto; Rimei Nishimura; Takashi Sasaki; Yoshito Hiki; Yumi Miyashita; Makiko Nishioka; Kei Fujimoto; Toru Sakuma; Toya Ohashi; Kunihiko Fukuda; Yoshikatsu Eto; Naoko Tajima

BackgroundAlthough oxidative stress by accumulation of reactive oxygen species (ROS) in diabetes has become evident, it remains unclear what genes, involved in redox balance, would determine susceptibility for development of atherosclerosis in diabetes. This study evaluated the effect of genetic polymorphism of enzymes producing or responsible for reducing ROS on coronary artery calcification in type 2 diabetes (T2D).MethodsAn index for coronary-arteriosclerosis, coronary artery calcium score (CACS) was evaluated in 91 T2D patients using a multi-slice computed tomography. Patients were genotyped for ROS-scavenging enzymes, Glutathione peroxidase-1 (GPx-1), Catalase, Mn-SOD, Cu/Zn-SOD, as well as SNPs of NADPH oxidase as ROS-promoting elements, genes related to onset of T2D (CAPN10, ADRB3, PPAR gamma, FATP4). Age, blood pressure, BMI, HbA1c, lipid and duration of diabetes were evaluated for a multivariate regression analysis.ResultsCACS with Pro/Leu genotype of the GPx-1 gene was significantly higher than in those with Pro/Pro (744 ± 1,291 vs. 245 ± 399, respectively, p = 0.006). In addition, genotype frequency of Pro/Leu in those with CACS ≥ 1000 was significantly higher than in those with CACS < 1000 (45.5% vs. 18.8%; OR = 3.61, CI = 0.97–13.42; p = 0.045) when tested for deviation from Hardy-Weinbergs equilibrium. Multivariate regression analyses revealed that CACS significantly correlated with GPx-1 genotypes and age.ConclusionThe presence of Pro197Leu substitution of the GPx-1 gene may play a crucial role in determining genetic susceptibility to coronary-arteriosclerosis in T2D. The mechanism may be associated with a decreased ability to scavenge ROS with the variant GPx-1.


American Journal of Roentgenology | 2006

Breast MRI Using the VIBE Sequence: Clustered Ring Enhancement in the Differential Diagnosis of Lesions Showing Non-Masslike Enhancement

Mitsuhiro Tozaki; Takao Igarashi; Kunihiko Fukuda

OBJECTIVE The purpose of this study was to assess the frequency of a finding in which minute ring enhancements are clustered (defined as clustered ring enhancement) in lesions showing non-masslike enhancement and to evaluate the clinical usefulness of this sign, in addition to that of the BI-RADS MRI descriptors, in the differentiation between benign and malignant lesions. MATERIALS AND METHODS Retrospective review was performed of 61 consecutive lesions showing non-masslike enhancement. MRI was performed on a 1.5-T system using the volumetric interpolated breath-hold examination (VIBE) sequence. The kinetic parameter was visually assessed as follows: washout, plateau, and persistent. RESULTS The most frequent morphologic finding among the malignant lesions was heterogeneous internal enhancement (69%) (p = 0.003), followed in frequency by segmental distribution (54%) (p < 0.001); whereas, stippled internal enhancement was the most frequent finding in benign lesions (50%) (p < 0.001). The presence of clustered ring enhancement was found in 63% of the malignant lesions and only 4% of the benign lesions (p < 0.001). The features with the highest positive predictive value for malignancy were a segmental distribution (100%), clustered ring enhancement (96%), and a washout pattern (94%). The specificity of clustered ring enhancement was 96% (25/26). In cases showing focal and regional enhancement, the combination of clumped internal architecture and clustered ring enhancement showed a statistically significant association with malignant lesions (p < 0.001). CONCLUSION Clustered ring enhancement is thought to be a useful sign to differentiate between benign and malignant lesions, in addition to the BI-RADS MRI descriptors.


The Journal of Rheumatology | 2010

Clinical Significance of Serum Levels of Vascular Endothelial Growth Factor, Angiopoietin-1, and Angiopoietin-2 in Patients with Rheumatoid Arthritis

Daitaro Kurosaka; Kenichiro Hirai; Makiko Nishioka; Yukio Miyamoto; Ken Yoshida; Kentaro Noda; Maimi Yanagimachi; Kazuhiro Furuya; Eigo Takahashi; Isamu Kingetsu; Kunihiko Fukuda; Akio Yamada

Objective. To evaluate the clinical significance of serum levels of vascular endothelial growth factor (VEGF), angiopoietin-1 (Ang-1), and angiopoietin-2 (Ang-2) in patients with rheumatoid arthritis (RA). Methods. The subjects were 70 patients with RA. Serum VEGF, Ang-1, and Ang-2 levels were determined by ELISA. As indices of disease activity, serum levels of C-reactive protein (CRP) and matrix metalloprotease (MMP)-3 were examined, and the 28-joint count Disease Activity Score (DAS28)-CRP was calculated. Power Doppler ultrasonography was performed in the bilateral wrists, elbows, shoulders, knees and ankles. The synovial blood flow signals were scored using a 3-grade scale (0–2), and the total of the scores in the 10 joints was regarded as the total signal score (TSS). Results. Serum VEGF level showed significant correlations with serum CRP and MMP-3 levels, DAS28-CRP, and TSS. Serum Ang-1 level showed significant correlations with serum MMP-3 level and DAS28-CRP. Serum Ang-2 level showed significant correlations with serum CRP level and TSS. Conclusion. The serum VEGF level is important as an index of the activity of RA based on angiogenesis and a prognostic factor regarding joint destruction. Serum Ang-1 level may be useful as an index of sustained arthritis based on the maintenance of newly formed vessels. Serum Ang-2 level may reflect a state of marked angiogenesis.


Skeletal Radiology | 1999

Peritumoral edema in osteoid osteoma on magnetic resonance imaging

Shigeru Ehara; Daniel I. Rosenthal; Jun Aoki; Kunihiko Fukuda; Hideharu Sugimoto; Hirokazu Mizutani; Kyoji Okada; Masahito Hatori; Masataka Abe

Abstract Objective.To determine whether there is a relationship between the peritumoral edema caused by osteoid osteoma seen on magnetic resonance (MR) imaging and the patient’s age, duration of symptoms, or location of the lesion. Design and patients. All histologically proven osteoid osteomas seen in our institutions during a 5-year period in patients with known age, gender, duration of symptoms, and available radiological and MR imaging examinations were included in this study. The extent of the edema in the bone marrow and extraosseous soft tissue around the nidus of osteoid osteoma on T2-weighted MR imaging were graded from 1 (nonexistent) to 4 (extensive) by two masked observers. The relationships between the patient’s age, duration of symptoms, and location of lesions were evaluated by Pearson’s correlation coefficient and analysis of variance. Results.Twenty-seven cases met the inclusion criteria. The observer agreement on grading was good. Patients of 15 years of age or younger had significantly higher grades than patients older than 15 years. There was a moderate negative linear correlation between the patient’s age and peritumoral edema. No significant relationship was identified between edema and the duration of symptoms or the location of lesions. Conclusion. Osteoid osteomas in younger patients tend to be associated with more extensive peritumoral edema.


Journal of Ultrasound in Medicine | 2001

Color/Power Doppler Sonographic Differential Diagnosis of Superficial Lymphadenopathy Metastasis, Malignant Lymphoma, and Benign Process

Takako Shirakawa; Yukio Miyamoto; Jiro Yamagishi; Kunihiko Fukuda; Shimpei Tada

Differentiation of lymph nodes as metastasis, malignant lymphoma, and benign lesions by gray scale and color/power Doppler ultrasonography has been reported. In this study we sought to determine patterns of abnormal vascularity, the relationship between diagnostic criteria and node size, and which vessel in the node was best suited for Doppler spectral analysis. Extrahilar vessels, defined as vessels entering through the lymphatic surface and not through the hilus, were also investigated.


American Journal of Roentgenology | 2006

Breast-conserving surgery after chemotherapy: value of MDCT for determining tumor distribution and shrinkage pattern.

Mitsuhiro Tozaki; Tadashi Kobayashi; Shinji Uno; Keisuke Aiba; Hiroshi Takeyama; Hisashi Shioya; Isao Tabei; Yasuo Toriumi; Masafumi Suzuki; Kunihiko Fukuda

OBJECTIVE For this study, we investigated the usefulness of MDCT in assessing the extent of residual breast cancer after neoadjuvant chemotherapy. To ensure the success of breast-conserving surgery, we evaluated the usefulness of determining the tumor distribution before neoadjuvant chemotherapy and the shrinkage pattern after neoadjuvant chemotherapy. SUBJECTS AND METHODS MDCT before and after neoadjuvant chemotherapy was performed in 46 consecutive patients with 47 locally advanced breast cancers. The distribution pattern of contrast enhancement on MDCT before neoadjuvant chemotherapy was classified into five categories: solitary lesion, grouped lesion (localized lesion with linear, spotty, or linear and spotty enhancement), separated lesion (multiple foci of contrast enhancement), mixed lesion (grouped lesion with multiple foci), and replaced lesion (diffuse contrast enhancement in whole quadrants). RESULTS There was agreement between the MDCT assessment and pathologic findings in 44 (94%) of the 47 tumors. In the partial response group with nonreplaced lesions, MDCT revealed three shrinkage patterns: pattern 1a, concentric shrinkage without surrounding lesions; pattern 1b, concentric shrinkage with surrounding lesions; and pattern 2, shrinkage with residual multinodular lesions. Breast-conserving surgery was performed successfully in 14 patients including complete response cases that were detected on the basis of MDCT findings and partial response cases that were detected on the basis of observation of pattern 1 shrinkage. In all five patients with pattern 2 shrinkage, CT underestimated the residual tumor extent by more than 2 cm. CONCLUSION MDCT classification of tumor distribution before neoadjuvant chemotherapy and of shrinkage patterns after neoadjuvant chemotherapy is important in the preoperative evaluation of patients undergoing breast-conserving surgery.


Arthritis & Rheumatism | 2010

Fasciitis as a common lesion of dermatomyositis, demonstrated early after disease onset by en bloc biopsy combined with magnetic resonance imaging.

Ken Yoshida; Daitaro Kurosaka; Kensuke Joh; Satoshi Matsushima; Eigo Takahashi; Kenichiro Hirai; Kentaro Noda; Kazuhiro Furuya; Maimi Yanagimachi; Isamu Kingetsu; Kunihiko Fukuda; Akio Yamada

OBJECTIVE To investigate whether fasciitis is histopathologically demonstrable in patients with dermatomyositis (DM), and to analyze the process of inflammatory progression in myopathy accompanying DM. METHODS STIR or fat-suppressed T2-weighted magnetic resonance imaging (MRI) and en bloc biopsy were performed in 14 patients with newly diagnosed adult-onset DM. The severity of inflammatory cell infiltration around the fascial and intramuscular small blood vessels was evaluated using the total vascular inflammation score (TVIS). RESULTS In all patients, MRI revealed abnormal hyperintensity in the fascia and in marginal sites of the muscle, predominantly over central sites. En bloc biopsy revealed the presence of fasciitis in most of the patients, as shown by inflammatory infiltrates around the fascial small blood vessels. In those patients who underwent en bloc biopsy earlier than 2 months after the appearance of muscle symptoms, the TVIS of the fascia was significantly higher than the TVIS of the muscle. In contrast, in those patients who underwent en bloc biopsy >2 months after muscle symptom onset, the TVIS of the fascia did not differ significantly from the TVIS of the muscle. CONCLUSION Fasciitis was histopathologically demonstrated in patients with newly diagnosed adult-onset DM as early as 2 months after the onset of muscle symptoms. These results indicate that fasciitis is a common lesion of DM and suggest that the fascial microvasculature is the primary site of inflammatory cell infiltration in DM. Fasciitis may contribute to muscle symptoms in patients with DM without myositis.


Journal of Computer Assisted Tomography | 2002

Dynamic multislice helical CT of ameloblastoma and odontogenic keratocyst: Correlation between contrast enhancement and angiogenesis

Katsuhiko Hayashi; Mitsuhiro Tozaki; Masashi Sugisaki; Nahoko Yoshida; Kunihiko Fukuda; Haruyasu Tanabe

Purpose The purpose of this study was to assess whether the enhancement characteristics of dynamic multislice helical CT (MS-CT) could help in the differential diagnosis of ameloblastomas and odontogenic keratocysts. The correlation between enhancement characteristics and immunohistochemical findings, especially with regard to angiogenesis, was also evaluated. Method Dynamic MS-CT was performed in 13 consecutive patients (8 ameloblastoma cases and 5 odontogenic keratocyst cases). The percentage of density increase (Enh%) was measured in dynamic MS-CT images taken during the arterial phase, and microvessel density (MVD) was analyzed using immunohistochemical study with anti-CD31 antibody. The Mann–Whitney U test was used to evaluate the significance of the Enh% or the MVD values between lesion subtypes, and the Spearman correlation coefficient was used to evaluate the correlation between the Enh% and the MVD in ameloblastomas and odontogenic keratocysts. Results The Enh% in ameloblastomas was significantly higher than that of odontogenic keratocysts (P < 0.005). The MVD of ameloblastomas was also significantly higher than that of odontogenic keratocysts (P < 0.005). The Enh% values for ameloblastomas and odontogenic keratocysts were positively correlated with the respective MVD values (r = 0.92, P ≤ 0.000). Conclusion Dynamic MS-CT is useful tool for differentiating between ameloblastomas and odontogenic keratocysts on the basis of the contrast enhancement values of intratumoral vascularities during the arterial phase. Furthermore, the Enh% obtained by dynamic MS-CT is correlated with the MVD in ameloblastomas and odontogenic keratocysts.


Journal of Computer Assisted Tomography | 2005

Dynamic magnetic resonance imaging of solitary pulmonary nodules : utility of kinetic patterns in differential diagnosis

Mitsuhiro Tozaki; Noriatsu Ichiba; Kunihiko Fukuda

Objective: The aim of this study was to evaluate the clinical feasibility of dynamic magnetic resonance (MR) imaging with a 3-dimensional (3D) gradient recalled echo (GRE) volumetric interpolated breath-hold examination (VIBE) sequence to differentiate between benign and malignant solitary pulmonary nodules (SPNs). Methods: Dynamic 3D GRE VIBE was performed in 45 patients with SPNs. For each lesion, the morphologic parameters, including the edge configuration, presence of peripheral enhancement (PE), and an internal signal on T2-weighted images, and the kinetic enhancement parameters were evaluated. Results: All 29 of the malignant SPNs had internal enhancement, whereas 13 (81%) of the benign SPNs did not exhibit internal enhancement. A washout pattern was only observed in the malignant SPNs. The presence of PE was found in 56% of the benign SPNs and in 50% of the malignant SPNs. The lesion size was significantly different between malignant SPNs with PE and those without PE (P < 0.01). The positive predictive value for malignancy was 91% (29 of 32 malignant SPNs). The negative predictive value was 100% (13 of 13 benign SPNs). Conclusions: A combination of morphologic criteria and kinetic information is useful for differentiating between benign and malignant SPNs. In particular, internal enhancement with PE and positive visual washout is thought be a useful tool.

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Mitsuhiro Tozaki

Jikei University School of Medicine

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Norio Nakata

Jikei University School of Medicine

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Toru Sakuma

Jikei University School of Medicine

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Yukio Miyamoto

Jikei University School of Medicine

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Shimpei Tada

Jikei University School of Medicine

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Junta Harada

Jikei University School of Medicine

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Daichi Hayashi

Jikei University School of Medicine

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Takao Igarashi

Jikei University School of Medicine

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Takenori Yonenaga

Jikei University School of Medicine

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