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Yuya Onodera

Publications and source records attributed to Yuya Onodera.

15 recordsLinked to original sources
PubMed2007

Virtual bronchoscopic navigation system shortens the examination time--feasibility study of virtual bronchoscopic navigation system.

Computed tomography (CT)-guided transbronchial biopsy (TBB) using an ultrathin bronchoscope with simulation by virtual bronchoscopy (VB) is effective for diagnosing small peripheral pulmonary lesions. However, we occasionally lose the proper bronchi to the lesion when a bronchoscope is inserted into peripheral bronchi with severe rotation. To overcome this problem, the virtual bronchoscopic navigation system that can display real-time VB images during TBB procedures in comparison with actual bronchi has been developed. We evaluated the usefulness of the virtual bronchoscopic navigation system for CT-guided TBB using an ultrathin bronchoscope (navigation method) to diagnose small peripheral pulmonary lesions, and compared the results to those with previous method that uses VB images in a simulation (simulation method). We performed CT-guided TBB using an ultrathin bronchoscope for 69 patients with 71 small peripheral pulmonary lesions (mean diameter, 13.7 mm) between November 2002 and November 2005 with the navigation method. CT-guided TBB with the navigation method was performed safely without any serious complications for all patients. Mean time to the initial scan, time to the first biopsy and total examination time were 5.3, 8.5 and 24.5 min, respectively. Fifty lesions (70%) were diagnosed by this procedure. Compared to simulation method, diagnostic sensitivity was higher in the navigation method, but the difference was not significant. However, the time to the first biopsy and total examination time were significantly shorter in the navigation method than in the simulation method (p<0.05). In summary, the virtual bronchoscopic navigation system was safely used, effective for diagnosing small peripheral pulmonary lesions, and useful for shortening the examination time of CT-guided TBB using an ultrathin bronchoscope.

Aged↗
PubMed2006

Separate analysis of asialoglycoprotein receptors in the right and left hepatic lobes using (99m)Tc-GSA SPECT in patients with acute hepatic damage.

The asialoglycoprotein receptor (ASGPR) is abundantly expressed on the sinusoidal surfaces of hepatocytes. However, regional expression and clinical significance of the ASGPR in acute hepatic damage is presently unknown. Our aim was to clarify the clinical significance of the regional expression of ASGPR in human livers with acute hepatitis (AH) and fulminant hepatic failure (FHF). Eighteen volunteers, 42 patients with AH and 10 with FHF were studied using a newly developed, conventional (99m)Tc-GSA SPECT analysis. Using Cantlie's line as a guide, ASGPR expression was analyzed separately in the right and left hepatic lobes, as well as in the whole liver, using novel indices (the liver uptake ratio [LUR] and liver uptake density [LUD], which reflect the amount and density of ASGPRs in the liver, respectively). Mean LUR and LUD values for the whole liver and the right and left lobes decreased in accordance with the severity of acute hepatic damage. In the FHF group, the reduction in LUR and LUD values in the right lobes was more significant than in the left lobes. The LUR and LUD values for the whole liver correlated well with hepatic functional reserve and total bilirubin levels. The right LUR and LUD values in particular correlated well with these parameters. A time-course observation of 13 patients with either AH or FHF revealed that the expression of ASGPRs in the right lobe recovered faster than in the left. We first evaluated the regional expression of AGSPRs by (99m)Tc-GSA SPECT analysis in both AH and FHF patients, which is a clinically useful and reliable indicator for assessing the severity of regional hepatic damage and evaluating regional liver regeneration.

Journal Article↗
PubMed2006

Airflow limitation and airway dimensions in chronic obstructive pulmonary disease.

RATIONALE: Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation caused by emphysema and/or airway narrowing. Computed tomography has been widely used to assess emphysema severity, but less attention has been paid to the assessment of airway disease using computed tomography. OBJECTIVES: To obtain longitudinal images and accurately analyze short axis images of airways with an inner diameter>or=2 mm located anywhere in the lung with new software for measuring airway dimensions using curved multiplanar reconstruction. METHODS: In 52 patients with clinically stable COPD (stage I, 14; stage II, 22; stage III, 14; stage IV, 2), we used the software to analyze the relationship of the airflow limitation index (FEV1, % predicted) with the airway dimensions from the third to the sixth generations of the apical bronchus (B1) of the right upper lobe and the anterior basal bronchus (B8) of the right lower lobe. MEASUREMENTS AND MAIN RESULTS: Airway luminal area (Ai) and wall area percent (WA%) were significantly correlated with FEV1 (% predicted). More importantly, the correlation coefficients (r) improved as the airways became smaller in size from the third (segmental) to sixth generations in both bronchi (Ai: r=0.26, 0.37, 0.58, and 0.64 for B1; r=0.60, 0.65, 0.63, and 0.73 for B8). CONCLUSIONS: We are the first to use three-dimensional computed tomography to demonstrate that airflow limitation in COPD is more closely related to the dimensions of the distal (small) airways than proximal (large) airways.

Adult↗
PubMed2006

Preoperative evaluation of hepatic vasculature by three-dimensional computed tomography in patients undergoing hepatectomy.

BACKGROUND: Hepatectomy is particularly difficult when the tumor is large, close to the inferior vena cava or the main trunk of the hepatic or portal vein, or in the caudate lobe, as well as when the operation is a re-hepatectomy, because two-dimensional computed tomography (CT) often does not clearly show tumor location relative to blood vessels. STUDY DESIGN: To evaluate the efficacy of three-dimensional computed tomography (3D-CT), reconstructed from multidetector-row computed tomography (MD-CT) with contrast, MD-CT was performed in 17 patients before hepatectomy. RESULTS: The third-order branches of the hepatic artery and the portal vein were clearly shown in all cases. Both the hepatic vein, which drained the same segment that the portal vein fed, and the portal vein were also clearly shown. These vessels could be visualized from any perspective. In 2 patients who underwent hemihepatectomy, large tumors (23.0 and 17.0 cm) displaced the vasculature, but the positions of tumor and vessels could be precisely evaluated by 3D-CT. In patients who required replacement of the vena cava with synthetic grafts, the distance and direction of pressure to IVC by tumor was accurately estimated by 3D-CT. In patients who were limited to segmentectomy or partial hepatectomy because of prior hepatectomy or tumor position, evaluation of the glissons was facilitated by 3D-CT. CONCLUSIONS: Three-dimensional-CT was extremely useful for preoperative simulation because it provided important information that could not be obtained with 2D-CT.

Adolescent↗
PubMed2006

Multiple mesenteric teratomas: usefulness of spiral computed tomography with 3-dimensional reconstruction.

A very rare case of mesenteric teratoma is reported. Complete tumor resection is the main prognostic factor for survival in such cases. Therefore, an important factor for successful surgery is the exact preoperative visualization of the extent of the tumor, including visualization of the abdominal arteries. This report describes the use of spiral computed tomography with 3-dimensional reconstruction for visualization of the extent of multiple mesenteric teratomas.

Child↗
PubMed2005

Transbronchial biopsy using endobronchial ultrasonography with a guide sheath and virtual bronchoscopic navigation.

STUDY OBJECTIVES: We evaluated the feasibility, safety, and efficacy of transbronchial biopsy (TBB) using endobronchial ultrasonography with a guide sheath (EBUS-GS) and virtual bronchoscopy (VB) navigation for small peripheral pulmonary lesions < or = 30 mm in diameter. DESIGN: Pilot study. SETTING: A national university hospital. PATIENTS: We performed TBB using EBUS-GS with VB navigation for 29 patients with 30 small peripheral pulmonary lesions (average diameter, 18.6 mm) between January 1, 2004, and August 31, 2004. INTERVENTIONS: VB images were reconstructed from helical CT data. TBB was then performed using EBUS-GS with VB navigation. RESULTS: In all patients, TBB was performed safely with no complications. Bronchi seen on VB imaging were highly consistent with the actual structures confirmed using fiberoptic bronchoscopy. Following VB navigation, the endobronchial ultrasonography (EBUS) probe was inserted into third- to sixth-generation bronchi. Twenty-four lesions (80%) were visualized on EBUS images. Average durations of the initial EBUS examination of lesions, first biopsy, and the total procedure were 9.56 min, 11.99 min, and 25.72 min, respectively. Nineteen lesions (63.3%) were diagnosed from histopathologic or cytologic examination. Diagnostic sensitivities were 44.4% (8 of 18) for lesions < 20 mm in mean diameter and 91.7% (11 of 12) for lesions 20 to 30 mm in mean diameter. CONCLUSIONS: In summary, TBB using EBUS-GS with VB navigation was safely performed and was effective in diagnosing small peripheral pulmonary lesions.

Adult↗
PubMed2004

CT-guided transbronchial biopsy using an ultrathin bronchoscope with virtual bronchoscopic navigation.

STUDY OBJECTIVES: We evaluated the feasibility, safety, and efficacy of CT-guided transbronchial biopsy (TBB) using an ultrathin bronchoscope with navigation by virtual bronchoscopy (VB) for small peripheral pulmonary lesions of < 20 mm in diameter. DESIGN: A pilot study. SETTING: A national university hospital. PATIENTS: We performed CT-guided TBB after VB navigation for 25 patients with 26 small peripheral pulmonary lesions (average diameter, 13.2 mm) between June 1, 2001, and October 31, 2002. Of the 26 lesions, 10 were in the right upper lobe, 2 were in the right middle lobe, 6 were in the right lower lobe, and 8 were in the left upper lobe. Nineteen lesions were not detected on chest radiographs. INTERVENTIONS: VB images were reconstructed from helical CT scans. CT-guided TBB was performed using an ultrathin bronchoscope after studying the VB image. RESULTS: CT-guided TBB was performed safely without any complications for all patients. The bronchi seen under VB imaging were highly consistent with the actual bronchi confirmed using an ultrathin bronchoscope. The ultrathin bronchoscope was inserted between the fifth and eighth generation bronchi. The average durations of the initial scan, the first biopsy, and the total examination were 5.46, 12.96, and 29.27 min, respectively. Seventeen lesions (65.4%) were diagnosed from pathology examinations (primary lung cancers, 13; atypical adenomatous hyperplasia, 1; metastatic cancer, 1; sarcoidosis, 1; and nontuberculous mycobacteriosis, 1). Diagnoses were not obtained for the remaining lesions due to an insufficient number of specimens (six specimens) or to the inability to reach the lesions even using the ultrathin bronchoscope (three specimens). CONCLUSIONS: In summary, CT-guided TBB using an ultrathin bronchoscope with VB navigation was safely performed and was effective for diagnosing small peripheral pulmonary lesions.

Aged↗
PubMed2004

Peripheral anatomic evaluation using 3D CT hepatic venography in donors: significance of peripheral venous visualization in living-donor liver transplantation.

OBJECTIVE: The purpose of this study was to determine clinical roles for 3D CT hepatic venography in the evaluation of peripheral hepatic venous anatomy during living-donor liver transplantation. MATERIALS AND METHODS: Subjects comprised 54 donors (age range, 20-60 years) who had undergone surgery to donate a liver for transplantation. Visualization of each hepatic venous branch and total visualization using 3D CT hepatic venography were evaluated. Maximum venous branch order visualized was graded as nil, first branch, second branch, or third branch or more. The distance between the hepatic surface and the tip of each hepatic venous branch was classified as 0-5 mm, 6-10 mm, 11-15 mm, 16-20 mm, or 21-25 mm. Quality of total 3D CT hepatic venography was evaluated subjectively as poor, good, fair, or excellent. Dominance of large hepatic veins in the right lobe, peripheral branching pattern of the middle hepatic vein, and branching pattern of the vein draining segment IVb were also assessed. RESULTS: Most hepatic venous branches (96.2% [275/286]) were visualized up to at least the second-order branches, and 93.7% (268/286) of branches were within 10 mm of the hepatic surface. As for total visualization, 98% (53/54) of cases were regarded as excellent. The dominant vein in the right lobe was the right hepatic vein in 27 cases, inferior hepatic vein in 25, and middle hepatic vein in one. The branching pattern of the middle hepatic vein was type 1 in 36 cases, type 2 in nine, and type 3 in eight. Segment IVb vein branched from the middle hepatic vein in 20 patients, and from the left hepatic vein in 34. CONCLUSION: Because 3D CT hepatic venography visualizes peripheral hepatic venous branches in detail, the technique is useful for determining operative indications in living-donor liver transplantation.

Adult↗
PubMed2004

Enhanced virtual bronchoscopy using the pulmonary artery: improvement in route mapping for ultraselective transbronchial lung biopsy.

OBJECTIVE: We evaluated a new simulation method for ultraselective transbronchial lung biopsy using the pulmonary artery. MATERIALS AND METHODS: A new method for enhanced virtual bronchoscopy using the pulmonary artery was developed for ultraselective transbronchial lung biopsy. In a volunteer study of healthy adults, three radiologists with different levels of experience independently reconstructed conventional virtual bronchoscopy and enhanced virtual bronchoscopy using the pulmonary artery until reaching the farthest point of the bronchus and pulmonary artery. The bronchovascular branch order and the minimum luminal diameter (e.g., for bronchus and artery) for reconstruction were compared. In a clinical study, virtual bronchoscopy and enhanced virtual bronchoscopy using the pulmonary artery were compared with regard to accessibility to target lesions in 40 patients with small pulmonary nodules or ground-glass opacities. A comparison between the simulated bronchial route reconstructions and actual bronchoscopic routes on biopsy was made to determine the efficacy of each reconstruction method. RESULTS: In the volunteer study, quality of enhanced virtual bronchoscopy using the pulmonary artery was not significantly affected by the experience levels of the radiologists. In the clinical study, bronchial reconstruction was successful in guiding to a bronchoscopic tumor in 35 (87.5%) of 40 cases. The maximum bronchial order on reconstruction was the sixth for the virtual bronchoscopy group and the eighth for the group with enhanced virtual bronchoscopy using the pulmonary artery (p < 0.001, Wilcoxon's signed rank test). The bronchial route reconstructed on enhanced virtual bronchoscopy using the pulmonary artery agreed with the actual biopsy routes in 30 cases (85.7%), but those reconstructed on virtual bronchoscopy alone agreed in only eight cases (22.9%) (p < 0.001, chi-square test). CONCLUSION: Enhanced virtual bronchoscopy using the pulmonary artery is feasible and helpful for ultraselective transbronchial lung biopsy of small nodules in the lung.

Aged↗
PubMed2003

Clinical assessment of hepatic functional reserve using 99mTc DTPA galactosyl human serum albumin SPECT to prognosticate chronic hepatic diseases--validation of the use of SPECT and a new indicator.

RATIONALE: It is generally known that scintigraphy of 99mTc diethylenetriamine pentaacetic acid-galactosyl human serum albumin (99mTc-GSA) is useful for assessing hepatic functional reserve. For hepatic functional indicators, the index of the calculated planar image has been used in previous studies. However, there have been few reports that suggest that the indicators calculated from static SPECT data would be useful for the assessment of hepatic function. The aims of this study were to establish a simple method for assessing hepatic functional reserve using the liver SPECT of 99mTc-GSA and to apply this method for rich stratification in patients with chronic hepatic diseases. METHODS: A liver phantom (a 50% concentration of 99mTc solution) was used to compare the planar and SPECT methods. According to the definition of the new indicator, the liver SPECT of 99mTc-GSA was divided by a syringe SPECT of 99mTc-GSA and was called the liver uptake ratio (LUR). We correlated the LUR and the liver uptake ratio calculated according to the blood-sampling method. 99mTc-GSA SPECT was performed in 137 patients with hepatic diseases, including chronic hepatic diseases, and 20 healthy volunteers. The LUR was correlated between the formed subtypes for all subjects. RESULTS: The acquired phantom-count ratio calculated by the SPECT method was more accurate than that acquired by the planar method. A good correlation was obtained between the LUR and the blood-sampling method (r = 0.971). The LUR was significantly lower in subjects with severe cirrhosis than in healthy subjects or those with chronic hepatitis and mild cirrhosis, and it was significantly lower in subjects with chronic hepatitis and mild cirrhosis than in healthy subjects. The LUR was significantly correlated with other hepatic function tests. Based on LUR, the chronic hepatic diseases were divided into two groups: Group A, with LURs 30% and higher, and Group B, with LURs below 30%. An LUR of 30% marked the 25th percentile of the mild-cirrhosis group. The cumulative survival rates were lower in Group B than in Group A. CONCLUSION: The SPECT method was superior to the planar method for assessing LURs. LUR was a suitable indicator of 99mTc-GSA clearance from the blood pool and of binding to the asialo-glycoprotein receptor. LUR is a simple and clinically useful indicator for the assessment of hepatic functional reserve in chronic hepatic diseases.

Chronic Disease↗
PubMed2003

Separate analysis of asialoglycoprotein receptors in the right and left hepatic lobes using Tc-GSA SPECT.

The asialoglycoprotein receptor (ASGPR) is abundantly expressed on the sinusoidal surfaces of hepatocytes. We aimed to clarify the clinical significance of the regional distribution of ASGPRs in the human liver, especially in chronic viral hepatitis. Eighteen volunteers, 34 patients with chronic hepatitis, and 33 patients with cirrhosis (11/Child-Pugh A, 11/Child-Pugh B, 11/Child-Pugh C) were studied using a newly developed, conventional technetium-99m-diethylenetriaminepentaacetic acid-galactosyl human serum albumin ((99m)Tc-GSA), single photon emission computed tomography (SPECT) method. Using Cantlie's line as a guide, ASGPR dynamics were analyzed separately in the right and left lobes, as well as in the whole liver, using novel indices (the liver uptake ratio [LUR] and the liver uptake density [LUD], which reflect the amount and density of ASGPRs in the liver, respectively). Mean LUR and LUD values for the whole liver and the right and left lobes decreased with increasing progression of chronic viral hepatitis. The LUR for the whole liver correlated well with parameters measuring the hepatic functional reserve and the platelet count. The right LUR correlated particularly well with conventional liver function tests, and comparison of the right LUD with histologic findings showed that it was a good indicator of periportal and/or bridging necrosis and fibrosis. In conclusion, our (99m)Tc-GSA SPECT method was clinically useful in evaluating regional hepatic function and the progression of chronic viral hepatitis using dynamic changes in ASGPRs.

Adult↗
PubMed2003

[A case of Mycobacterium avium pulmonary disease detected as multiple small nodular shadows and diagnosed by CT guided transbronchial biopsy with ultrathin bronchoscopy].

A 65-year-old man was admitted to our hospital because multiple small nodular shadows measuring five to 12 mm in diameter in both lung fields were noticed on chest radiographs and CT scans during a regular checkup for pulmonary emphysema. The levels of ESR and CRP were within normal limits, but those of CEA and CYFRA were slightly elevated. Mycobacterium avium (M. avium) was detected in sputum cultures and in a sputum examination using PCR. Non-necrotizing granulomas were detected in the specimens obtained from a lesion of the right S6b by CT-guided transbronchial biopsy using an ultrathin bronchoscope after navigation with virtual bronchoscopy. On the basis of these findings, M. avium pulmonary disease was diagnosed. The patient is being followed up, but because he has no symptoms, without medication. To our knowledge, there have been no previous reports of M. avium-intracellulare complex pulmonary disease, which is characterized by multiple small nodular shadows. It is speculated that multiple centrilobular lesions developed simultaneously without extension to the bronchial walls, leading in this case to multiple small nodules in both lung fields.

Aged↗
PubMedDate not supplied

Mediastinal lymph node staging by FDG-PET in patients with non-small cell lung cancer: analysis of false-positive FDG-PET findings.

BACKGROUND: Accurate staging of mediastinal and hilar lymph nodes is a critical factor determining operability in patients with non-small cell lung cancer (NSCLC). Positron emission tomography with 2-[18F] fluoro-2-deoxy-D-glucose as a tracer (FDG-PET) has recently been reported to be more effective in detecting tumor involvement in mediastinal and hilar lymph nodes than computed tomography (CT). OBJECTIVE: In this study, we analyzed the accuracy of FDG-PET in mediastinal and hilar lymph node staging in patients with NSCLC and the factors associated with false-positive or false-negative FDG-PET findings in mediastinal and hilar lymph node staging. METHODS: Fifty-four patients with NSCLC who underwent preoperative analysis including chest CT and whole-body FDG-PET were evaluated retrospectively. Using FDG-PET, lesions were considered to be positive if a definite, localized area of higher uptake, excluding physiologic uptake, than in surrounding normal tissue was present. On CT findings, lymph nodes were considered to be positive if they were >10 mm in short-axis diameter, except subcarinal lymph nodes (#7), which were considered to be positive if they were >15 mm in short-axis diameter. All patients underwent surgical resection of primary tumors and mediastinal and hilar lymph nodes between 1999 and 2001 in our institute. Resected lymph nodes were histologically examined for the existence of tumor cells. RESULTS: A total of 306 lymph nodes were resected and used for analysis. The sensitivity, specificity, positive predictive value and negative predictive value of FDG-PET were 73, 98, 70 and 98%, while those of CT were 55, 96, 55 and 96%, respectively. When pre-operative nodal staging was compared with post-operative histopathological staging, 44 patients (81%) were correctly staged, 7 (13%) were overstaged and 3 (6%) were understaged by FDG-PET, while 39 patients (72%) were correctly staged, 8 (15%) were overstaged and 7 (13%) were understaged by CT. All 7 overstaged patients by FDG-PET had other pulmonary complications, including interstitial pneumonitis (n = 2), previous pulmonary tuberculosis (n = 3), silicosis (n = 1) and emphysema (n = 1), although they were not in the active stage. In 3 understaged patients by FDG-PET, lymph nodes were also undetectable by CT. CONCLUSION: FDG-PET is superior to CT in mediastinal and hilar lymph node staging of patients with NSCLC. However, care should be taken in lymph node staging for patients who have other pulmonary complications, including interstitial pneumonitis, previous pulmonary tuberculosis and silicosis.

Adenocarcinoma↗