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Kunihiko Fukuda

Publications and source records attributed to Kunihiko Fukuda.

16 recordsLinked to original sources
PubMed2005

Supine MR mammography using VIBE with parallel acquisition technique for the planning of breast-conserving surgery: clinical feasibility.

Volumetric interpolated breath-hold examination (VIBE), which provides both high-spatial and high-temporal resolution images, is a useful sequence for determining the extent of breast cancer. The VIBE sequence in combination with the parallel acquisition technique allows for a single breath-hold evaluation of the breast. We evaluated the clinical feasibility of MR mammography in the supine oblique position (supine MRM) using this technique for planning breast conservation surgery. The accuracy of determination of the tumor extent with a deviation of less than 2 cm in length was 90% (36/40). Two cases showed a positive surgical margin (7.4%). Supine MRM is feasible for the planning of breast-conserving surgery.

Adult↗
PubMed2005

New diagnostic technique in multi-slice computed tomography for in-stent restenosis: pixel count method.

OBJECTIVES: A diagnostic technique to objectively determine coronary in-stent stenosis was developed with multi(16)-slice computed tomography (MSCT), and it was compared with coronary angiography (CAG) in clinical cases. BACKGROUND: MSCT is expected to replace coronary angiography as a new non-invasive examination. Evaluation of highly calcified or in-stent lesions with CT is generally thought to be difficult. METHODS: Twenty lesions among 16 consecutive patients that were implanted with coronary stents were examined with both MSCT and CAG at follow-up. The minor axis cross sections of the stents were reconstructed at intervals of 1.5 mm with multiplanar reformation (MPR). The pixel with a higher CT value than the lowest CT value in the standard cross section at the proximal site out of stent was counted to determine the presence/absence of a stenotic lesion. RESULTS: Among 20 lesions, one case was not able to be evaluated with MSCT. MSCT correctly detected 3 of 4 cases with in-stent stenosis (sensitivity 75%), and 14 of 16 cases with no in-stent stenosis (specificity 88%, negative predictive value 93%, positive predictive value 75%). If analysis was made per-artery, sensitivity and specificity were 100% (3 of 3) and 87% (13 of 15), respectively, for detection of in-stent stenosis. CONCLUSIONS: This study was performed to examine a unique diagnostic technique: pixel count method, for coronary in-stent stenosis with MSCT. It showed that the coronary in-stent stenosis could be determined when stent struts were clearly imaged. Further examination is required with various stents, especially those with a diameter of 3.0 mm or smaller.

Adult↗
PubMed2005

High-spatial-resolution MR imaging of focal breast masses: interpretation model based on kinetic and morphological parameters.

PURPOSE: To assess a new interpretation model combining kinetic pattern and morphologic characteristics using high-spatial-resolution MR imaging. MATERIALS AND METHODS: Breast MR imaging was performed in 58 patients with 63 pathologically proved focal breast masses (49 malignant and 14 benign). MR imaging was performed on a 1.5-Tesla system using the volumetric interpolated breath-hold examination (VIBE) sequence. Morphological parameters were lesion shape, mass margin, rim enhancement (RE), enhancing internal septations, and internal signal on T2-weighted images. Lesion shape/margin was classified into four categories as follows: smooth (smooth/round or smooth/oval), lobulated (lobular shape), irregular (irregular margin or irregular shape), and spiculated (spiculated margin). RE was sub-classified as early RE at 60 sec and delayed RE at 4 min. Strongly high signal and the presence of internal black septations were evaluated over the entire lesion on T2-weighted images. The kinetic parameter was visually assessed as follows: washout, plateau, and progressive. RESULTS: The most frequent types of lesion shape/margin in the malignant lesions were irregular (47%) and spiculated (43%), whereas 13 of the benign lesions had smooth or lobular margins (93%). The most frequent characteristics in breast cancers with lobulated configuration were washout pattern (80%), whereas 78% of the lobulated benign lesions were negative for visual washout. The positive predictive value (PPV) was 98% (49/50). CONCLUSION: "Washout with enhancing septations" is thought be specific for carcinoma with a lobulated configuration (80%). A combination of morphological criteria (including lesion shape/margins, strongly high signal on T2-weighted images) and visual washout is useful for differentiating between benign and malignant lesions.

Adult↗
PubMed2005

[Transcatheter arterial embolization of unresectable hepatocellular carcinoma: does selective treatment improve outcome?].

PURPOSE: To evaluate whether selective transcatheter arterial embolization (TAE) contributes to preservation of liver function and improves local control and survival in patients with hepatocellular carcinoma. MATERIALS AND METHODS: One hundred patients with hepatocellular carcinoma who underwent single or multiple TAE were retrospectively analyzed. The incidence of deterioration of liver function caused by TAE was compared between patients with Child class A disease and those having Child B/C disease. The correlation between extent of embolization and incidence of deterioration of liver function was analyzed. In addition, factors affecting deterioration of liver function after TAE were determined. Recurrence-free and overall survival rate were calculated using the Kaplan-Meier method. A Cox proportional hazard model was used to analyze prognostic factors affecting recurrence-free and overall survival. RESULTS: The incidence of deterioration of liver function in the Child B/C group (47%) was significantly higher than that in the Child A group (21%). Pretreatment Child-Pugh classification and extent of embolization were significant factors in the deterioration of liver function after TAE. Recurrence-free survival rates at 1, 2, and 3 years were 38%, 19%, and 8%, respectively. Overall survival rates at 1, 3, 5, and 7 years were 89%, 59%, 22%, and 22%, respectively. Findings of multivariate analyses of prognostic factors showed that tumor size and selectivity of TAE were significant for recurrence-free survival and the initial Child-Pugh classification was the most important factor for overall survival. CONCLUSION: Selective TAE improves local control and avoids damage to nontumorous liver tissue. The selective technique appears to be associated with a favorable outcome.

Aged↗
PubMed2004

[Urologic area].

In this review, the clinical experience of a three-dimensional(3D) image at urologic area are described. There are some methods for reconstructive 3D image of Multi-slice CT. Maximum intensity projection (MIP) is usefulness for detection of vascular anatomy. Multi-planar reconstruction (MPR) is usefulness for relation with circumference organs. Therefore the opportunities of angiography decreased. It seems that an applied range of a 3D image spreads more in future.

Female Urogenital Diseases↗
PubMed2003

MR-guided percutaneous cryotherapy of malignant liver tumor under horizontal-magnetic open system: initial experience.

BACKGROUND/PURPOSE: We describe the feasibility and accuracy of magnetic resonance (MR)-guided cryotherapy for malignant liver tumor, using a horizontal-magnetic open system. METHODS: Using an MR-compatible cryotherapy system and horizontal-magnetic open-configuration MR scanner, we performed percutaneous cryotherapy for four malignant liver tumors. RESULTS: All procedures were carried out safely and accurately without any serious complication. Residual tumor was observed in one patient with metastatic liver tumor located directly under the diaphragm. CONCLUSIONS: MR-guided cryotherapy appears to be ideal and desirable as a minimally invasive therapy for liver tumor.

Aged↗
PubMed2003

[Multi-section magnetic susceptibility perfusion echo-planar imaging of the breast].

PURPOSE: To examine the diagnostic value of multi-section magnetic susceptibility perfusion echo-planar imaging (perfusion EPI) in patients with breast tumors prior to T1-weighted dynamic MRI. MATERIALS AND METHODS: MR imaging was performed in 75 patients with pathologically proved breast tumors using a 1.5 Tesla MR unit (MAGNETOM Symphony, Siemens Medical Solutions, Erlangen, Germany). Perfusion EPI was carried out before, during, and after the bolus injection of 0.1 mmol Gd-DTPA/kg. Two patients had two carcinomas in the same breast, one patient had both a benign and a malignant lesion in the same breast, and two patients had lesions in both breasts. Histopathological diagnosis was non-invasive ductal carcinoma in 9, invasive carcinoma in 49, and benign lesion in 22. The first-pass signal intensity loss of the lesions was calculated by perfusion EPI. RESULTS: Fifty-one of 58 carcinomas but only 4 of 22 benign lesions had a signal intensity loss of 20% or more during the first pass, for a sensitivity of 88% and specificity of 82% CONCLUSION: Perfusion EPI can be used as a useful diagnostic tool for differentiation between benign and malignant lesions. It is also thought to be a promising method for diagnosing multifocal breast lesions.

Adult↗
PubMed2002

[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↗
PubMedDate not supplied

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↗
PubMedDate not supplied

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↗
PubMedDate not supplied

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↗
PubMedDate not supplied

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↗
PubMedDate not supplied

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↗
PubMedDate not supplied

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↗
PubMedDate not supplied

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↗