Publications (337) View all
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Article: CT With Hepatic Arterioportography as a Pretreatment Examination for Hepatocellular Carcinoma Patients: A Randomized Controlled Trial.
Takamasa Ohki, Ryosuke Tateishi, Masaaki Akahane, Shintaro Mikami, Masaya Sato, Koji Uchino, Toru Arano, Kenichiro Enooku, Yuji Kondo, Noriyo Yamashiki, Tadashi Goto, Shuichiro Shiina, Haruhiko Yoshida, Yutaka Matsuyama, Masao Omata, Kuni Ohtomo, Kazuhiko Koike[show abstract] [hide abstract]
ABSTRACT: OBJECTIVES:The combination of computed tomography with hepatic arteriography and arterial portography (CTHA/CTAP) can detect additional hepatocellular carcinoma (HCC) nodules undetected by conventional dynamic CT.METHODS:In this single-center, randomized, open-label, controlled trial, we randomly assigned 280 patients who were diagnosed as having HCC by conventional dynamic CT, and eligible for radiofrequency ablation (RFA), to undergo CTHA/CTAP before treatment, or to the control group. Newly detected HCC nodules by CTHA/CTAP were intended to be ablated completely. The primary end point was recurrence-free survival and the key secondary end point was overall survival. The analysis was conducted on an intention-to-treat basis. Those with nonablated nodules were treated as for recurrence.RESULTS:A total of 75 nodules were newly diagnosed as HCC by CTHA/CTAP in 45 patients. Three patients (one in the CTHA/CTAP group and two in the control group) who refused treatment were excluded from all analyses. The cumulative recurrence-free survival rates at 1, 2, and 3 years were 60.1, 29.0, and 18.9% in the CTHA/CTAP group and 52.2, 29.7, and 23.1% in the control group, respectively (P=0.66 by log-rank test; hazard ratio, 0.94 for CTHA/CTAP vs. control; 95% confidence interval (CI), 0.73-1.22). The cumulative overall survival rates at 3 and 5 years were 79.7 and 56.4% in the CTHA/CTAP group and 86.8 and 60.1% in the control group, respectively (P=0.50; hazard ratio, 1.15, 95% CI, 0.77-1.71).CONCLUSIONS:CTHA/CTAP may detect recurrent lesions earlier. However, CTHA/CTAP before RFA did not improve cumulative recurrence-free survival or overall survival.Am J Gastroenterol advance online publication, 30 April 2013; doi:10.1038/ajg.2013.109.The American Journal of Gastroenterology 04/2013; · 7.28 Impact Factor -
Article: Santorinicele without pancreas divisum pathophysiology: Initial clinical and radiographic investigations.
Wataru Gonoi, Hiroyuki Akai, Kazuchika Hagiwara, Masaaki Akahane, Naoto Hayashi, Eriko Maeda, Takeharu Yoshikawa, Shigeru Kiryu, Minoru Tada, Kansei Uno, Naoki Okura, Kazuhiko Koike, Kuni Ohtomo[show abstract] [hide abstract]
ABSTRACT: BACKGROUND: Only one case of santorinicele without pancreas divisum pathophysiology (SWOPP) was previously reported. The purpose of the study was to determine the gross prevalence of SWOPP and santorinicele with pancreas divisum (SWPD) in community and patient populations, and investigate their clinical and radiographic features. METHODS: This cross-sectional study was performed at a tertiary referral centre. The Patient group comprised 2035 consecutive patients enrolled in the study who underwent magnetic resonance cholangiopancreatography (MRCP) studies. The Community group comprised 2905 consecutive subjects who participated in our whole-body medical check-up program that routinely includes MRCP studies. SWOPP was diagnosed when a saccular dilatation of the terminal portion of the dorsal pancreatic duct was observed unaccompanied by pancreas divisum or dominant dorsal duct. The prevalence of SWOPP and SWPD, and the clinical and radiological features were assessed in each group. RESULTS: Five cases of SWOPP were found in the Patient group (age range, 67--85 years; mean age, 73.6 years) (5/2035 = 0.25%; 95% confidence interval, 0.07--0.57); there were no cases of SWOPP in the Community group (0/2905 = 0.00%; 95% confidence interval, 0.00--0.10) (P = 0.01). Previous history of pancreatitis (4/5) and chronic pancreatitis (3/5) was more common in patients with SWOPP than in other subjects in the Patient or Community groups (both P < 0.05). Two cases of SWOPP were accompanied by reverse-Z type meandering main pancreatic duct. Six cases of SWPD were found. These cases were asymptomatic in 4/6, had a larger santorinicele (6.9 mm) than SWOPP patients (4.5 mm; P = 0.02), and were not associated with pancreatitis (0/6). CONCLUSIONS: The second to sixth reported cases of SWOPP were presented. SWOPP is a relatively rare condition found mostly in patients suffering pancreatitis, especially chronic pancreatitis, and may be an acquired condition. Santorinicele is not always accompanied by pancreas divisum.BMC Gastroenterology 04/2013; 13(1):62. · 2.42 Impact Factor -
Article: Effect of saline flush on enhancement of proximal and distal segments using 320-row coronary CT angiography.
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ABSTRACT: OBJECTIVE: To investigate the effect of saline flush on coronary CT angiography of proximal, middle, and distal coronary artery segments, using 320-row CT, and to compare two injection duration protocols as to amount of contrast in the right heart chambers. METHODS: This retrospective study was approved by the local ethics committee, and the requirement for informed consent to participate in this study was waived. The final study group included 108 patients who underwent coronary CT angiography. The first 36 patients received contrast medium without saline flush (group 1); the next 36 patients received contrast medium for 14s and saline flush (group 2); the last 36 patients received contrast medium for 12s and saline flush (group 3). The CT number, noise, contrast-to-noise ratio (CNR), and number of segments with a CT number greater than 325 Hounsfield units (HU) were recorded for proximal, middle, and distal segments. RESULTS: The CT numbers and the CNR in groups 2 and 3 were significantly higher than that in group 1 (p<0.005); the difference between groups 2 and 3 was not significant. The proportion of segments greater than 325HU improved with saline flush (p<0.05), with a larger improvement in the distal segments. CONCLUSIONS: Saline flush improves enhancement and CNR of coronary arteries, particularly of distal segments, in coronary CT angiography using 320-row CT. An average contrast medium injection of 44mL was feasible using a saline flush.European journal of radiology 04/2013; · 2.65 Impact Factor -
Article: Verification of Planning Target Volume Settings in Volumetric Modulated Arc Therapy for Stereotactic Body Radiation Therapy by Using In-Treatment 4-Dimensional Cone Beam Computed Tomography.
Wataru Takahashi, Hideomi Yamashita, Satoshi Kida, Yoshitaka Masutani, Akira Sakumi, Kuni Ohtomo, Keiichi Nakagawa, Akihiro Haga[show abstract] [hide abstract]
ABSTRACT: PURPOSE: To evaluate setup error and tumor motion during beam delivery by using 4-dimensional cone beam computed tomography (4D CBCT) and to assess the adequacy of the planning target volume (PTV) margin for lung cancer patients undergoing volumetric modulated arc therapy for stereotactic body radiation therapy (VMAT-SBRT). METHODS AND MATERIALS: Fifteen lung cancer patients treated by single-arc VMAT-SBRT were selected in this analysis. All patients were treated with an abdominal compressor. The gross tumor volumes were contoured on maximum inspiration and maximum expiration CT datasets from 4D CT respiratory sorting and merged into internal target volumes (ITVs). The PTV margin was isotropically taken as 5 mm. Registration was automatically performed using "pre-3D" CBCT. Treatment was performed with a D95 prescription of 50 Gy delivered in 4 fractions. The 4D tumor locations during beam delivery were determined using in-treatment 4D CBCT images acquired in each fraction. Then, the discrepancy between the actual tumor location and the ITV was evaluated in the lateral, vertical, and longitudinal directions. RESULTS: Overall, 55 4D CBCT sets during VMAT-SBRT were successfully obtained. The amplitude of tumor motion was less than 10 mm in all directions. The average displacements between ITV and actual tumor location during treatment were 0.41 ± 0.93 mm, 0.15 ± 0.58 mm, and 0.60 ± 0.99 mm for the craniocaudal, left-right, and anteroposterior directions, respectively. The discrepancy in each phase did not exceed 5 mm in any direction. CONCLUSIONS: With in-treatment 4D CBCT, we confirmed the required PTV margins when the registration for moving target was performed using pre-3D CBCT. In-treatment 4D CBCT is a direct method for quantitatively assessing the intrafractional location of a moving target.International journal of radiation oncology, biology, physics 04/2013; · 4.59 Impact Factor -
Article: Dose verification of volumetric modulated arc therapy (VMAT) by use of in-treatment linac parameters.
Akihiro Haga, Akira Sakumi, Yukari Okano, Saori Itoh, Naoya Saotome, Satoshi Kida, Hiroshi Igaki, Kenshiro Shiraishi, Hideomi Yamashita, Kuni Ohtomo, Keiichi Nakagawa[show abstract] [hide abstract]
ABSTRACT: Linac parameters such as the multi-leaf collimator (MLC) position and jaw position, cumulative monitor units (MUs), and the corresponding gantry angle were recorded during the clinical delivery of volumetric modulated arc therapy for prostate, lung, and head/neck cancer patients. Then, linac parameters were converted into the beam-data format used in the treatment planning system, and the dose distribution was reconstructed. The dose-volume histogram and the dose difference (DD) were compared with the corresponding values in the treatment plan. A reproducible error of in-treatment linac parameters was observed when a sudden change of beam intensity or MLC/jaw speed occurred. The maximum cumulative MU error was more than 4 MU for lung cancer cases, and the maximum MLC position exceeded 5 mm for prostate and head/neck cancer patients. However, these errors were quickly compensated for at the next control point. All treatments analyzed in the present study were delivered within 0.4 % accuracy at the planning target volume. The cumulative dose agreed with that of the plan within 3 % of the prescribed dose. The 1 % DD was 93.9, 99.9, and 93.4 % of the prescription dose for prostate, lung, and head/neck cancer patients, respectively.Radiological Physics and Technology 03/2013;