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Kunihiko Fukuda

Publications and source records attributed to Kunihiko Fukuda.

26 records · Page 2Linked to original sources

[The usefulness of MDCT in Crohn's disease].

The usefulness of multidetector-row CT (MDCT) was investigated in 27 patients with Crohn's disease. MDCT depicted characteristic lesions associated with Crohn's disease, including bowel wall thickening, strictures, bowel wall enhancement with contrast, opacity of fatty tissue and mesenteric lymph node enlargement. With respect to delineation of lesion sites, a 76% or higher correlation rate was observed between MDCT and other conventional diagnostic procedures such as colonoscopy, barium enema, small bowel examination, and gastrointestinal endoscopy. The patient were classified as either with active disease or in remission based on the Crohn's disease activity index (CDAI). We then compared MDCT findings in patients with active disease and in remission. A positive correlation (r = 0.70) between CDAI and bowel wall thickening was observed. A comparison of 13 patients with active disease versus 14 patients in remission revealed significant bowel wall thickening, mesenteric lymph node enlargement, and opacity of fatty tissue. MDCT accurately depicted lesions consistent with active Crohn's disease. MDCT is a minimally invasive procedure that is useful in the evaluation of acute active Crohn's disease.

Crohn Disease↗

Enhanced four-detector row computed tomography imaging of laryngeal and hypopharyngeal cancers.

PURPOSE: Four-detector row computed tomography (4D CT) enables imaging of the larynx and hypopharynx with high temporal resolution and rapid reformatting of coronal planes. The aim of our study was to assess the usefulness of postcontrast biphasic 4D CT in diagnosing tumor extent. METHODS: Forty-seven patients with laryngeal or hypopharyngeal cancer were investigated using 4D CT. Two radiologists retrospectively evaluated transverse and reformatted coronal images in both the early and late phases. RESULTS: Images in the late phase were superior to those in the early phase in the conspicuity of the depicted lesions. The coronal images facilitated assessment of the craniocaudal extension of tumors and obliteration of the paraglottic space. The maximal diameter of tumors tended to be larger on the coronal image than on the transverse image. CONCLUSIONS: Images in the late phase were more informative than images in the early phase to demonstrate tumor extension. Reformatted coronal imaging was useful in evaluating craniocaudal extension.

Adult↗

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

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 < or = 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.

Adult↗

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

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.

Adult↗

Informatics in Radiology (infoRAD): mobile wireless DICOM server system and PDA with high-resolution display: feasibility of group work for radiologists.

A novel mobile system has been developed for use by radiologists in managing Digital Imaging and Communications in Medicine (DICOM) image data. The system consists of a mobile DICOM server (MDS) and personal digital assistants (PDAs), including a Linux PDA with a video graphics array (VGA) display (307,200 pixels, 3.7 inches). The MDS weighs 410 g, has a 60-GB hard disk drive and a built-in wireless local area network (LAN) access point, and supports a DICOM server (Central Test Node). The Linux-based MDS can be accessed with personal computers (PCs) and PDAs by means of a wireless or wired LAN, and client-server communications can be established at any time. DICOM images can be displayed by using any PDA or PC by means of a Web browser. Simultaneous access to the MDS is possible for multiple authenticated users. With most PDAs, image compression is necessary for complete display of DICOM images; however, the VGA screen can display a 512 x 512-pixel DICOM image almost in its entirety. This wireless system allows efficient management of heavy loads of lossless DICOM image data and will be useful for collaborative work by radiologists in education, conferences, and research.

Computers, Handheld↗

Diagnosis of Tis/T1 breast cancer extent by multislice helical CT: a novel classification of tumor distribution.

PURPOSE: To evaluate the clinical usefulness of multislice helical CT (MSCT) for assessing breast cancer extent. MATERIALS AND METHODS: MSCT was performed in 70 patients with Tis/T1 breast cancer [12 ductal carcinoma in situ (DCIS) and 58 invasive carcinoma]. The distribution pattern of contrast enhancement (CE) was classified into five categories: solitary lesion (localized area of CE), grouped lesion (satellite: localized CE with linear and/or spotty enhancement; crowded: clustered spotty enhancement), separated lesion (multifocal foci of CE), mixed lesion (grouped lesion with multifocal foci), and diffuse lesion (diffuse CE). RESULTS: Solitary lesion was seen in five cases of DCIS, 27 invasive carcinomas without intraductal spread (IDS), six invasive carcinomas with IDS, and one multicentric cancer. Grouped lesion was seen in six DCIS and 15 invasive carcinomas with IDS. Separated lesion was seen in one case of invasive carcinoma and fibroadenoma, and three multifocal/multicentric cancers. Mixed lesion was seen in two multicentric cancers. Diffuse lesion was seen in one case of DCIS and three invasive carcinomas. The coincident rate between MSCT pattern and histologic distribution was 85.7% (60/70). In solitary and grouped lesions, accuracy for the detection of tumor extent with a deviation of less than 2 cm in length was 91.7% (55/60). CONCLUSION: MSCT is extremely accurate in the diagnosis of IDS and the multicentricity of breast cancer.

Adult↗

Histologic breast cancer extent after neoadjuvant chemotherapy: comparison with multidetector-row CT and dynamic MRI.

PURPOSE: To evaluate the efficacy of dynamic multidetector-row CT (MDCT) in assessing residual cancer extent after neoadjuvant chemotherapy (NAC), and to compare MDCT results with those derived from dynamic three-dimensional MRI using the volumetric interpolated breath-hold examination (VIBE) sequence. MATERIALS AND METHODS: MDCT before and after NAC was performed in 19 consecutive patients with breast cancer. MRI was also performed before surgery. The early phase of MDCT and MRI was started 60 sec after commencing contrast injection. The late phase was started at a 4-min delay from the injection. The injection rate was 3 mL/sec. The distribution pattern of contrast enhancement (CE) by CT before NAC was classified into two groups: replaced lesion (diffuse CE in whole quadrants) and non-replaced lesion (localized CE). RESULTS: Pathological complete response (pCR) was obtained in one case. In replaced lesions, accuracy for the detection of tumor extent with a deviation of less than 2 cm in length was 0% (0/7) with early-phase CT/MRI and 100% (7/7) with late-phase CT/MRI. In non-replaced lesions, accuracy was 55% (6/11) with early-phase CT/MRI and 82% (9/11) with late-phase CT/MRI. One case of ductal carcinoma in situ (DCIS) could be detected only with late phase MRI. CONCLUSION: Late-phase images obtained by MDCT and MRI may be accurate in the diagnosis of residual cancer extent after NAC. The tumor distribution determined by MDCT before NAC is thought to be useful in the evaluation of shrinkage pattern following NAC.

Adult↗

MR-guided transvaginal cryotherapy of uterine fibroids with a horizontal open MRI system: initial experience.

PURPOSE: We evaluated the feasibility of MR-guided transvaginal cryotherapy for treating intramural, submucosal, and sub-serosal uterine fibroids with a horizontal open MRI system. MATERIALS AND METHODS: Using an MR-compatible cryotherapy system and a horizontal magnetic open-configuration MR scanner, we performed transvaginal cryotherapies using a Cusco speculum on eight uterine fibroids whose longest diameter ranged from 2.9 to 10.0 cm. We assessed the ratio of pre-treatment to post-treatment volume of the uterine fibroids as well as the patients' symptoms (anemia, abdominal pain, dysfunctional uterine bleeding, etc.). RESULTS: All procedures were carried out safely and accurately without any complications that required surgical treatment. MRI enabled clear visualization of the cryoneedle and freezing area as band-like and ellipsoid-like signal losses, respectively. The mean ratio of reduction in uterine fibroid volume was 31.0% at 9-12 months (0-75.0%). Symptoms caused by uterine fibroids improved in seven cases. CONCLUSION: This is the first report on a transvaginal approach to cryotherapy for uterine fibroids. MR-guided transvaginal cryotherapy appears to be feasible and promising as a minimally invasive therapy for symptomatic uterine fibroids.

Abdominal Pain↗