Takeyuki Watadani

The University of Tokyo, Edo, Tōkyō, Japan

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Publications (22)35.48 Total impact

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    ABSTRACT: We present a case of a 69-year-old man with primary hepatic carcinosarcoma who underwent computed tomography that revealed a hypervascular hepatic tumor with local dense calcification. Gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging revealed hyperintense lesions in the hepatobiliary phase that indicated hepatocellular carcinoma with bile production. The patient underwent right lobectomy, and the presence of a sarcoma component within the tumor on histopathology confirmed liver carcinosarcoma that included hepatocellular carcinoma. In cases with atypical images that resemble this case, the hyperintensity of a lesion in the hepatobiliary phase aids differential diagnosis.
    Magnetic Resonance in Medical Sciences 04/2014; · 0.75 Impact Factor
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    ABSTRACT: Honeycombing on CT is the clue for the diagnosis of usual interstitial pneumonia (UIP) and its hallmark. According to the ATS-ERS-JRS-ALAT 2010 guideline, the patients with honeycombing on CT can be diagnosed as UIP without surgical biopsy. On CT scans, it is defined as clustered cystic airspaces, typically of comparable diameters of the order of 3-10mm, which are usually subpleural and have well-defined walls. Pathologically, honeycombing consists of both collapsing of multiple fibrotic alveoli and dilation of alveolar duct and lumen Although the definition of honeycombing seems to be strict, recognition of honeycombing on CT is various among each observer Because typical honeycombing is frequently observed in the patients with UIP, we should judge clustered cysts as honeycombing when a diagnosis of UIP is suspected.
    European journal of radiology 06/2013; · 2.65 Impact Factor
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    ABSTRACT: Purpose:To quantify observer agreement and analyze causes of disagreement in identifying honeycombing at chest computed tomography (CT).Materials and Methods:The institutional review board approved this multiinstitutional HIPAA-compliant retrospective study, and informed patient consent was not required. Five core study members scored 80 CT images with a five-point scale (5 = definitely yes to 1 = definitely no) to establish a reference standard for the identification of honeycombing. Forty-three observers from various subspecialties and geographic regions scored the CT images by using the same scoring system. Weighted κ values of honeycombing scores compared with the reference standard were analyzed to investigate intergroup differences. Images were divided into four groups to allow analysis of imaging features of cases in which there was disagreement: agreement on the presence of honeycombing, agreement on the absence of honeycombing, disagreement on the presence of honeycombing, and other (none of the preceding three groups applied).Results:Agreement of scores of honeycombing presence by 43 observers with the reference standard was moderate (Cohen weighted κ values: 0.40-0.58). There were no significant differences in κ values among groups defined by either subspecialty or geographic region (Tukey-Kramer test, P = .38 to >.99). In 29% of cases, there was disagreement on identification of honeycombing. These cases included honeycombing mixed with traction bronchiectasis, large cysts, and superimposed pulmonary emphysema.Conclusion:Identification of honeycombing at CT is subjective, and disagreement is largely caused by conditions that mimic honeycombing.© RSNA, 2012.
    Radiology 12/2012; · 6.34 Impact Factor
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    ABSTRACT: Patients with hepatocellular carcinoma (HCC) complicated by portal vein tumor thrombus (PVTT) have an extremely poor prognosis. It is important to select adequate therapeutic options based on reliable prognostic factors using imaging studies and clinical data. Prognostic factors were analyzed in patients with HCC with PVTT in the first branch or main trunk of the portal vein. From 2000 to 2007, 107 consecutive patients with HCC with PVTT in the major portal vein were reviewed, and diagnostic images and clinical characteristics were retrospectively observed. Thirty-eight possible prognostic factors for survival were analyzed by the log-rank test and multivariate analysis using Cox's proportional hazards model. Median overall survival was 14 months following PVTT diagnosis. Survival rates at 6 months, 1, 2, and 3 years were 72.1%, 52.6%, 32.6%, and 29.6%, respectively. Independent prognostic factors for longer survival included:patient age < 65 years, Child-Pugh classification A/B, PVTT treatment, accumulation of Lipiodol in the PVTT after TACE, initial radical treatment for HCC, HCC located in a single lobe of the liver, and no invasion of HCC to the hepatic vein or bile duct. Survival was associated with liver function, tumor extension, and treatment for HCC and PVTT.
    Acta medica Okayama 04/2012; 66(2):131-41. · 0.65 Impact Factor
  • Akira Uchino, Naoko Saito, Takeyuki Watadani
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    ABSTRACT: We present what we believe is the first report of external carotid-internal carotid artery anastomosis, which forms a large arterial ring at the proximal cervical internal carotid artery (ICA). If the small channel of the proximal cervical ICA is occluded, the remaining large channel of the external carotid artery may be diagnosed as a nonbifurcating cervical carotid artery.
    Journal of neuroimaging: official journal of the American Society of Neuroimaging 06/2011; · 3.36 Impact Factor
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    ABSTRACT: A nonbifurcating cervical carotid artery is a branching anomaly in which the ECA has no proximal main trunk. We report its incidence and characteristic features on MRA. We retrospectively reviewed MRAs of 2866 patients obtained by using a standard noncontrast MRA protocol and two 1.5T MR imaging units and reviewed the English language literature to assess the occurrence and features of this nonbifurcating artery. We diagnosed 6 cases, indicating an incidence of 0.21%, and found 11 cases reported in the literature. Analysis of all 17 cases demonstrated no laterality or sex predominance. The most prevalent pattern of branching order from proximal to distal was the F-L trunk, the distal trunk of the ECA, and the OA. A nonbifurcating cervical carotid artery is rare but not as extremely rare as previously considered, and its correct diagnosis is necessary to avoid complications during interventional radiologic procedures or head and neck surgeries.
    American Journal of Neuroradiology 06/2011; 32(6):1119-22. · 3.17 Impact Factor
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    ABSTRACT: The craniovertebral junction is clinically important. The vertebral artery (VA) in its several variations runs within this area. We report the prevalence of these VA variations on magnetic resonance angiography (MRA). We retrospectively reviewed MRA images, obtained using two 1.5-T imagers, of 2,739 patients, and paid special attention to the course and branching of the VA at the level of the C1-2 vertebral bodies. There were three types of VA variation at the C1-2 level: (1) persistent first intersegmental artery (FIA), (2) VA fenestration, and (3) posterior inferior cerebellar artery (PICA) originating from the C1/2 level. The overall prevalence of these three variations was 5.0%. There was no laterality in frequency, but we found female predominance (P < 0.05). We most frequently observed the persistent FIA (3.2%), which was sometimes bilateral. We found VA fenestration (0.9%) and PICA of C1/2 origin (1.1%) with almost equal frequency. Two PICAs of C1/2 origin had no normal VA branch. We frequently observed VA variations at the C1-2 level and with female predominance. The persistent FIA was most prevalent and sometimes seen bilaterally. Preoperative identification of these variations in VA is necessary to avoid complications during surgery at the craniovertebral junction.
    Neuroradiology 02/2011; 54(1):19-23. · 2.70 Impact Factor
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    ABSTRACT: PURPOSE Honeycomb lung (Hc) is one of the most important findings in the evaluation of interstitial pneumonia (IP). Purposes of the study are to investigate interobserver difference of Hc diagnosis and investigate the causes of the discordance. METHOD AND MATERIALS Eighty HRCT images (single image per one patient) of Hc and mimickers (without pathological confirmation) were collected from 30 chest radiologists and chest physicians. Hc and UIP diagnosis was determined by the consensus of 5 experienced chest radiologists. Forty-two observers (18 domestic and overseas expert chest radiologists in IP, 10 board-certified chest radiologists, 5 non-chest board-certified radiologists and 9 chest physicians majoring in IP) scored five points scale (5 = definite, 4 = probable, 3 = possible 2 = probably not, 1 = definite not ) to evaluate the probability of Hc and usual interstitial pneumonia (UIP) pattern. Concordance of Hc diagnosis among observers and groups, concordance of Hc and UIP diagnosis were investigated. RESULTS In general, concordance of Hc diagnosis is not so good (k values range from 0.47 to 0.56) among expert radiologists, board-certified chest radiologists and chest physicians, while, concordance in non-chest radiologists is relatively low (k= 0.4). Worldwide interregional concordance of expert radiologists were approximately same (k ranges 0.52 to 0. 56), except relatively low concordance rate of North America (k=0.47), however: not statistically significant. Wide range of concordance rate was observed within each observer group and between observers in same regions. The cases showing discordant Hc diagnosis included IP with emphysema, cluster of very large cyst, cluster of traction bronchiectasis, single layered alignment of cysts, small areas of multilayer constellation of cysts. Kappa value of Hc and UIP score in each observer varies widely (0.2 to 0.9). CONCLUSION Concordance rate of atypical Hc is not so high even among experienced chest radiologists. The different score of Hc is seen in cases with small extent of multicystic shadow, single layered alignment of cyst, and prominent destructive change with cluster of large cysts or severe emphysema. CLINICAL RELEVANCE/APPLICATION It should be remained that relatively wide variation in Hc diagnosis. Attention must be paid to use the term of “honeycomb lung”.
    Radiological Society of North America 2010 Scientific Assembly and Annual Meeting; 11/2010
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    ABSTRACT: We report three cases with a rare anatomic variation, in which the common hepatic artery (CHA) arose from the left gastric artery. Fewer than ten cases with this anatomic variation have been published in the literature consulted. In each patient, multidetector-row CT image with 3D reformation demonstrated that the hepatic artery arises from the left gastric artery and runs through the lesser omentum. The left, middle, and right hepatic arteries derived from this artery, and no other arterial supply to the liver was seen. The course of the gastroduodenal artery was variable; it derived from the CHA, the splenic artery, or both. No variation was noted in the splenic artery and the superior mesenteric artery.
    Anatomia Clinica 04/2010; 32(7):703-5. · 0.93 Impact Factor
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    ABSTRACT: Late-onset noninfectious pulmonary complications (LONIPCs) are life threatening for allogeneic hematopoietic SCT (allo-HSCT) recipients. However, the impact of LONIPCs on survival has not been properly evaluated and little is known about treatment efficacy. We retrospectively investigated 290 allo-HSCT recipients in our institute and reviewed the clinical aspects of 44 patients who had been diagnosed with LONIPCs. LONIPCs were significantly associated with higher rates of chronic GVHD (P<0001) and nonrelapse mortality (P=0.013), and lower rates of relapse (P=0.009). As a result of these effects, OS was significantly worse in those with LONIPCs (P=0.003). This result differs from a previous report. We then assessed short-term treatment response and final outcome. These results were defined by radiological findings, subjective symptoms, oxygen requirement and survival. Use of inhaled and systemic steroids did not affect either short-term response or final outcomes. However, administration of systemic corticosteroids earlier than at 21 days (median interval of time from onset of symptoms to systemic corticosteroids administration) was associated with a better outcome (P=0.054 for short-term response, and 0.016 for final outcome). Our study indicates that LONIPCs reduce OS, and early intervention with systemic corticosteroids may be effective.
    Bone marrow transplantation 03/2010; 45(12):1719-27. · 3.00 Impact Factor
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    ABSTRACT: The uncinate fasciculus (UF) consists of core fibers connecting the frontal and temporal lobes and is considered to be related to cognitive/behavioral function. Using diffusion tensor tractography, we quantitatively evaluated changes in fractional anisotropy (FA) and the apparent diffusion coefficient (ADC) of the UF by tract-specific analysis to evaluate the damage of the UF in patients with amyotrophic lateral sclerosis (ALS). We obtained diffusion tensor images of 15 patients with ALS and 9 age-matched volunteers. Patients with ALS showed significantly lower mean FA (P = 0.029) compared with controls. No significant difference was seen in mean ADC. The results suggest that damage of the UF in patients with ALS can be quantitatively evaluated with FA.
    Neuroradiology 02/2010; 52(8):729-33. · 2.70 Impact Factor
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    ABSTRACT: Imaging findings of low-grade fibromyxoid sarcoma (LGFMS) are reported in three thoracic cases, two in the mediastinum and one in the chest wall. The multinodular intralesional structure with strongly enhancing components in the periphery and components with abrupt transition may be suggestive of LGFMS. Strongly enhancing areas correlated with the hypercellular zone, and weakly enhancing areas correlated with the myxoid zone with less cellularity, or hyalinization. No differences in vasculature densities between the myxoid and fibrous zones were demonstrated.
    Japanese journal of radiology 11/2009; 27(9):375-80. · 0.73 Impact Factor
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    ABSTRACT: Hepatic transarterial interventional therapies such as chemoembolization and radiation embolization are important treatment options for hepatocellular carcinoma. Understanding the anatomy of individual arterial branches and hepatic segments is critical for selecting the correct embolization technique for treatment and to avoid complications. The authors describe the morphologic characteristics of hepatic arterial branches (and their mimickers) and hepatic segments on conventional angiograms. These vessels and segments include the celiac artery, the common and proper hepatic arteries, the left and right hepatic arteries and branches, the caudate lobe, and the portal vein and branches. Mimickers of hepatic arteries include the cystic, accessory left gastric, and right gastric arteries, as well as branches of the left gastric artery that resemble segmental branches of the replaced left hepatic artery. The authors describe how each segmental branch of the hepatic artery and the area it supplies correlates at computed tomography (CT) and angiography. Finally, the authors demonstrate how the vascular anatomy changes with the respiratory cycle by creating a virtual movie from calculations with dynamic CT data, in which the arterial and venous phases are acquired at end expiration and inspiration, respectively. Each segmental branch of the hepatic artery has morphologic characteristics that help distinguish it from mimickers. The location of each hepatic segment can be estimated if the artery supplying the segment can be correctly identified on angiograms. Notably, morphologic differences in the hepatic artery system caused by respiration should be recognized.
    Radiographics 10/2009; 29(7):1-22. · 2.79 Impact Factor
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    ABSTRACT: Our aim was to investigate the diagnostic reliability of multidetector-row computed tomography (MDCT) for preoperative assessment of local tumoral spread in hilar cholangiocarcinoma. MATEIRALS AND METHODS: Thirteen of 30 consecutive patients with hilar cholangiocarcinoma who underwent surgery, excluding 17 patients who underwent biliary drainage or preoperative portal embolization, were retrospectively evaluated. Using MDCT systems of 4 detector rows or 16 detector rows, plain and dynamic contrast-enhanced images of three phases were obtained. Extent of tumor spread and lymph node metastasis were assessed with MDCT and compared with histopathological findings. The Bismuth-Corlette classification of hilar cholangiocarcinoma with MDCT were type I, 1 patient; type IIIa, 3 patients; type IIIb, 4 patients; and type IV, 5 patients; those with histopathological findings were type I, 1 patient; type IIIa, 2 patients; type IIIb, 4 patients; and type IV, 6 patients. One patient diagnosed as type IIIa with MDCT was pathologically diagnosed as type IV. Accuracy of MDCT in tumoral spread was 92.3%, although that of lymph node metastasis was 54%. MDCT is likely to play an important role in evaluation of focal lesion spread especially in intrapancreatic tumor invasion, although a greater number of cohort cases are necessary to clearly define its role.
    Radiation Medicine 09/2008; 26(7):402-7.
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    ABSTRACT: Hepatic hemangiomatosis is a rare condition characterized by diffuse replacement of liver parenchyma with tissue similar to that of cavernous hemangioma. The purpose of this report is to illustrate two adult cases of hepatic hemangiomatosis and to review the pathological, radiological and clinical issues of this condition. The first case is that of a 47-year-old woman with extensive involvement of the entire liver. The right lobe was almost totally replaced, and only a limited amount of residual hepatic parenchyma was present in the left lobe. The second case is that of a 31-year-old woman with less extensive involvement. The right lobe was almost totally involved, and was accompanied with a large hematoma. The left lobe was relatively unaffected. Both cases were complicated by consumption coagulopathy (Kasabach–Merritt syndrome). The patients were successfully managed surgically, with living donor liver transplantation in the first case and extensive right lobectomy in the second case. The condition described by the term hepatic hemangiomatosis includes a wide clinical spectrum, with some cases asymptomatic, some accompanied with shunting, and some resulting in rupture or life-threatening hepatic failure. The disease has a good overall prognosis, with surgery and arterial embolization as effective treatment options.
    European Journal of Radiology Extra. 01/2007;
  • European Radiology 01/2006; 15(12):2528-31. · 4.34 Impact Factor
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    ABSTRACT: Septal penetration of high energy photons may degrade 123I images obtained with a low energy collimator. We evaluated the physical characteristics of a low energy, high resolution (LEHR) collimator, special LEHR (SLEHR) collimator, and medium energy collimator for 123I studies. The cross-talk of 99mTc and 123I into the 201Tl window was also examined. Sensitivity and spatial resolution were measured with each collimator. Point sources of 99mTc and 123I were imaged at various source-collimator distances using multiple energy windows, and the effects of collimator choice on energy spectrum and spatial distribution of photopeak counts were assessed. For 99mTc, both sensitivity and resolution were similar with the low energy collimators, and higher sensitivity and lower resolution were observed with the medium energy collimator. For 123I, the full width at tenth maximum was larger for 123I than for 99mTc when using the LEHR collimator. Acquisitions with multiple energy windows revealed severe degradation due to septal penetration in imaging 123I with the LEHR collimator, especially at short distances. The degradation was reduced with the SLEHR collimator and further with the medium energy collimator. In both 99mTc and 123I imaging, cross-talk into the 201Tl window was larger at shorter distances and the largest with the LEHR collimator. In conclusion, variation in collimator geometry causes differences in the effect of septal penetration on 123I images and in cross-talk into the 201Tl window. The SLEHR collimator may be suitable for use in high resolution 123I imaging and simultaneous 99mTc/201Tl imaging. Use of the medium energy collimator appears to be preferable in quantitative 123I studies.
    Nuclear Medicine Communications 11/2003; 24(11):1195-202. · 1.38 Impact Factor
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    ABSTRACT: PURPOSE/AIM The purpose of this exhibit is to expose interventional radiologists to a series of mimickers and pitfalls in order to avoid technical failure and serious complications. CONTENT ORGANIZATION * Tumor stain or not? - Gastric mucosa - Adrenal gland - Renal parenchyma - Pleura - Lymph node - Misregistration - Arterioportal shunt * Feeding artery or not? - Accessory left gastric artery - Inferior phrenic artery - Epicholedochal plexus - Cystic artery - Renal capsular artery - Hepatic falciform ligament artery * Patent of not? - Occlusion of the branch of right lobe concealed by hypertrophic left lobe - Altered blood flow due to the stenotic celiac axis SUMMARY 1. Interventional radiologists should be familiar with mimickers of the tumor stain in order to avoid unnecessary and harmful chemoembolization. 2. Some of the feeding arteries from outside of the liver may be chemoembolized safely, and some may not. 3. Hepatic artery and portal vein should be examined in comparison with each other to detect occlusion and aberrancy.
    Radiological Society of North America 2006 Scientific Assembly and Annual Meeting;
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    ABSTRACT: PURPOSE/AIM Frequency of systemic CT scan for detecting the cause of "fever of unknown origin" is recently increasing. However, distinctive imaging findings could not always be pointed out. In this education exhibit, faint or uncommon but important CT findings to approaching the causes of undiagnosed inflammatory processes are presented in case-based quiz format. CONTENT ORGANIZATION * Autoimmune disease - Systemic lupus erythematosus - Takayasu arteritis - Behcet's disease - Polyarteritis nodosa - Relapsing polychondritis - IgG4-related sclerosing disease * Infection - Tuberculosis - Infectious endocarditis - Spondylodiskitis * Other - Multicentric Castleman's disease - Sarcoidosis - SAPHO syndrome - Familial mediterranean fever - Erdheim-Chester disease SUMMARY Even though the cause is common disease, it is often difficult to identify the origin of fever in systemic CT scan. However, less common or faint findings in routine imaging can be the important clues to reaching correct diagnosis. In addition, knowledges of relatively rare inflammatory diseases help radiologists to contribute solving clinical problems.
    Radiological Society of North America 2012 Scientific Assembly and Annual Meeting;
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    ABSTRACT: PURPOSE/AIM The purpose of this education exhibit is to inform radiation oncologists and diagnostic radiologists about imaging findings of complications after radiotherapy to utilize them for better treatment planning and posttreatment management. CONTENT ORGANIZATION * Central Nervous System - radiation necrosis - leukoencephalopathy - radiation induced hemangioma / vascular malformation - myelitis * Lung - radiation pneumonitis * Gastrointestinal system - esophagitis / enteritis / colitis - fistula formation - liver dysfunction * Genitouninary system - renal dysfunction - cystitis * Bone - osteoporosis - insufficient fracture - bone marrow dysfunction - radiation induced multiple exostoses * Other - seed migration after brachytherapy SUMMARY Radiotherapy is absolutely imperative therapeutic approach in clinical oncology, however, various side effects and complications after radiotherapy is recognized including acute, subacute and chronic onset. Radiologists and radiation oncologists should know imaging findings of these complications.
    Radiological Society of North America 2009 Scientific Assembly and Annual Meeting;

Publication Stats

82 Citations
35.48 Total Impact Points

Institutions

  • 2006–2013
    • The University of Tokyo
      • • Department of Radiology
      • • Faculty & Graduate School of Medicine
      Edo, Tōkyō, Japan
  • 2009
    • Tokyo Medical University
      • Division of Radiology
      Edo, Tōkyō, Japan