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Yanyan Xu,1,2 Tsuneo Yamashiro,1,3 Hiroshi Moriya,3 Shun Muramatsu,3 Sadayuki Murayama1 1Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Okinawa, Japan; 2Department of Radiology, China-Japan Friendship Hospital, Beijing, People’s Republic of China; 3Department of Radiology, Ohara General Hospital, Fukushima, JapanCorrespondence: Tsuneo YamashiroDepartment of Radiology, Graduate School of Medical Science, University of the Ryukyus, 207 Uehara, Nishihara, Okinawa 903-0215, JapanTel +81-98-895-1162Fax +81-98-895-1420Email clatsune@yahoo.co.jpPurpose: To evaluate the advantages of ultra-high-resolution computed tomography (U-HRCT) scans for the quantitative measurement of emphysematous lesions over conventional HRCT scans.Materials and methods: This study included 32 smokers under routine clinical care who underwent chest CT performed by a U-HRCT scanner. Chronic obstructive pulmonary disease (COPD) was diagnosed in 13 of the 32 participants. Scan data were reconstructed by 2 different protocols: i) U-HRCT mode with a 1024×1024 matrix and 0.25-mm slice thickness and ii) conventional HRCT mode with a 512×512 matrix and 0.5-mm slice thickness. On both types of scans, lesions of emphysema were quantitatively assessed as percentage of low attenuation volume (LAV%,

Yanyan Xu,1,2 Tsuneo Yamashiro,1 Hiroshi Moriya,3 Maho Tsubakimoto,1 Yukihiro Nagatani,4 Shin Matsuoka,5 Sadayuki Murayama1 On behalf of ACTIve Study Group 1Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Nishihara, Okinawa, Japan; 2Department of Radiology, China-Japan Friendship Hospital, Beijing, Republic of China; 3Department of Radiology, Ohara General Hospital, Fukushima-City, Fukushima, Japan; 4Department of Radiology, Shiga University of Medical Science, Otsu, Shiga, Japan; 5Department of Radiology, St Marianna University School of Medicine, Kawasaki, Kanagawa, Japan Purpose: Strain measurement is frequently used to assess myocardial motion in cardiac imaging. This study aimed to apply strain measurement to pulmonary motion observed by four-dimensional dynamic-ventilation computed tomography (CT) and to clarify motion abnormality in COPD. Materials and methods: Thirty-two smokers, including ten with COPD, underwent dynamic-ventilation CT during spontaneous breathing. CT data were continuously reconstructed every 0.5 seconds. In the series of images obtained by dynamic-ventilation CT, five expiratory frames were identified starting from the peak inspiratory frame (first expiratory frame) and ending with the fifth expiratory frame. Strain measurement of the scanned lung was performed using research software that was originally developed for cardiac strain measurement and modified for assessing deformation of the lung. The measured strain values were divided by the change in mean lung density to adjust for the degree of expiration. Spearman’s rank correlation analysis was used to evaluate associations between the adjusted strain measurements and various spirometric values. Results: The adjusted strain measurement was negatively correlated with FEV1/FVC (ρ=-0.52, P

Yukihiro Nagatani,1 Masayuki Hashimoto,2 Norihisa Nitta,1 Yasuhiko Oshio,2 Tsuneo Yamashiro,3 Shigetaka Sato,1 Shinsuke Tsukagoshi,4 Hiroshi Moriya,5 Tatsuya Kimoto,6 Tomoyuki Igarashi,2 Noritoshi Ushio,1 Akinaga Sonoda,1 Hideji Otani,1 Jun Hanaoka,2 Kiyoshi Murata1On behalf of investigators of the ACTIve Study Group1Department of Radiology, Shiga University of Medical Science, Otsu, Shiga 520-2192, Japan; 2Department of Surgery, Division of General Thoracic Surgery, Shiga University of Medical Science, Otsu, Shiga 520-2192, Japan; 3Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Nishihara, Okinawa 903-0215, Japan; 4CT System Division, Canon Medical Systems, Otawara, Tochigi 324-8550, Japan; 5Department of Radiology, Ohara General Hospital, Fukushima, Fukushima 960-8611, Japan; 6Healthcare IT Development Center, Canon Medical Systems, Otawara, Tochigi 324-8550, JapanPurpose: The purpose of this study was to measure changes in lung density and airway dimension in smokers in the lateral position using four-dimensional dynamic-ventilation computed tomography (CT) during free breathing and to evaluate their correlations with spirometric values.Materials and methods: Preoperative pleural adhesion assessments included dynamic-ventilation CT of 42 smokers (including 22 patients with COPD) in the lateral position, with the unoperated lung beneath (dependent lung). The scanned lungs’ mean lung density (MLD) and the bilateral main bronchi’s luminal areas (Ai) were measured automatically (13–18 continuous image frames, 0.35 seconds/frame). Calculations included cross-correlation coefficients (CCCs) between the MLD and Ai time curves, and correlations between the quantitative measurements and spirometric values were evaluated by using Spearman’s rank coefficient.Results: The ΔMLD1.05 (from the peak inspiration frame to the third expiratory frame, 1.05 seconds later) in the nondependent lung negatively correlated with FEV1/FVC (r=-0.417, P

Yanyan Xu,1,2 Tsuneo Yamashiro,1 Hiroshi Moriya,3 Maho Tsubakimoto,1 Nanae Tsuchiya,1 Yukihiro Nagatani,4 Shin Matsuoka,5 Sadayuki Murayama1 On behalf of the ACTIve Study Group 1Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Nishihara, Japan; 2Department of Radiology, China-Japan Friendship Hospital, Beijing, People’s Republic of China; 3Department of Radiology, Ohara General Hospital, Fukushima, Japan; 4Department of Radiology, Shiga University of Medical Science, Otsu, Japan; 5Department of Radiology, St Marianna University School of Medicine, Kawasaki, Japan Purpose: The aims of this study were to evaluate dynamic changes in heart size during the respiratory cycle using four-dimensional computed tomography (CT) and to understand the relationship of these changes to airflow limitation in smokers.Materials and methods: A total of 31 smokers, including 13 with COPD, underwent four-dimensional dynamic-ventilation CT during regular breathing. CT data were continuously reconstructed every 0.5 s, including maximum cross-sectional area (CSA) of the heart and mean lung density (MLD). Concordance between the cardiac CSA and MLD time curves was expressed by cross-correlation coefficients. The CT-based cardiothoracic ratio at inspiration and expiration was also calculated. Comparisons of the CT indices between COPD patients and non-COPD smokers were made using the Mann–Whitney test. Spearman rank correlation analysis was used to evaluate associations between CT indices and the forced expiratory volume in 1 s (FEV1.0) relative to the forced vital capacity (FVC).Results: Cardiac CSA at both inspiration and expiration was significantly smaller in COPD patients than in non-COPD smokers (P

Tsuneo Yamashiro,1 Hiroshi Moriya,2 Shin Matsuoka,3 Yukihiro Nagatani,4 Maho Tsubakimoto,1 Nanae Tsuchiya,1 Sadayuki Murayama1 On behalf of the ACTIve Study Group 1Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Nishihara, Okinawa, Japan; 2Department of Radiology, Ohara General Hospital, Fukushima-City, Fukushima, Japan; 3Department of Radiology, St Marianna University School of Medicine, Kawasaki, Kanagawa, Japan; 4Department of Radiology, Shiga University of Medical Science, Otsu, Shiga, Japan Purpose: Four-dimensional dynamic-ventilation CT imaging demonstrates continuous movement of the lung. The aim of this study was to assess the correlation between interlobar synchrony in lung density and spirometric values in COPD patients and smokers, by measuring the continuous changes in lung density during respiration on the dynamic-ventilation CT. Materials and methods: Thirty-two smokers, including ten with COPD, underwent dynamic-ventilation CT during free breathing. CT data were continuously reconstructed every 0.5 sec. Mean lung density (MLD) of the five lobes (right upper [RU], right middle [RM], right lower [RL], left upper [LU], and left lower [LL]) was continuously measured by commercially available software using a fixed volume of volume of interest which was placed and tracked on a single designated point in each lobe. Concordance between the MLD time curves of six pairs of lung lobes (RU-RL, RU-RM, RM-RL, LU-LL, RU-LU, and RL-LL lobes) was expressed by cross-correlation coefficients. The relationship between these cross-correlation coefficients and the forced expiratory volume in one second/forced vital capacity (FEV1.0/FVC) values was assessed by Spearman rank correlation analysis. Results: In all six pairs of the pulmonary lobes, the cross-correlation coefficients of the two MLD curves were significantly positively correlated with FEV1.0/FVC (ρ =0.60–0.73, P

Tsuneo Yamashiro,1 Hiroshi Moriya,2 Maho Tsubakimoto,1 Shin Matsuoka,3 Sadayuki Murayama1 On behalf of ACTIve Study Group 1Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Nishihara, Okinawa, 2Department of Radiology, Ohara General Hospital, Fukushima-shi, Fukushima, 3Department of Radiology, St Marianna University School of Medicine, Kawasaki, Kanagawa, Japan Purpose: Four-dimensional dynamic-ventilation computed tomography (CT) imaging demonstrates continuous movement of the airways and lungs, which cannot be depicted with conventional CT. We aimed to investigate continuous changes in lung density and airway dimensions and to assess the correlation with spirometric values in smokers.Materials and methods: This retrospective study was approved by the Institutional Review Board, and informed consent was waived. Twenty-one smokers including six patients with COPD underwent four-dimensional dynamic-ventilation CT during free breathing (160 mm in length). The mean lung density (MLD) of the scanned lung and luminal areas (Ai) of fixed points in the trachea and the right proximal bronchi (main bronchus, upper bronchus, bronchus intermedius, and lower bronchus) were continuously measured. Concordance between the time curve of the MLD and that of the airway Ai values was expressed by cross-correlation coefficients. The associations between these quantitative measurements and the forced expiratory volume in 1 second/forced vital capacity (FEV1/FVC) values were assessed by Spearman’s rank correlation analysis.Results: On the time curve for the MLD, the Δ-MLD1.05 values between the peak inspiratory frame to the later third frame (1.05 seconds later) were strongly correlated with the FEV1/FVC (ρ=0.76, P

Tsuneo Yamashiro,1 Maho Tsubakimoto,1 Yukihiro Nagatani,2 Hiroshi Moriya,3 Kotaro Sakuma,3 Shinsuke Tsukagoshi,4 Hiroyasu Inokawa,5 Tatsuya Kimoto,5 Ryuichi Teramoto,6 Sadayuki Murayama1 1Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Nishihara, Okinawa; 2Department of Radiology, Shiga University of Medical Science, Otsu; 3Department of Radiology, Ohara General Hospital, Fukushima; 4CT Systems Division, 5Center for Medical Research and Development, Toshiba Medical Systems Corporation, Otawara; 6Corporate Manufacturing Engineering Center, Toshiba Corporation, Yokohama, Japan Background: The purpose of this study was to evaluate the feasibility of continuous quantitative measurement of the proximal airways, using dynamic ventilation computed tomography (CT) and our research software. Methods: A porcine lung that was removed during meat processing was ventilated inside a chest phantom by a negative pressure cylinder (eight times per minute). This chest phantom with imitated respiratory movement was scanned by a 320-row area-detector CT scanner for approximately 9 seconds as dynamic ventilatory scanning. Obtained volume data were reconstructed every 0.35 seconds (total 8.4 seconds with 24 frames) as three-dimensional images and stored in our research software. The software automatically traced a designated airway point in all frames and measured the cross-sectional luminal area and wall area percent (WA%). The cross-sectional luminal area and WA% of the trachea and right main bronchus (RMB) were measured for this study. Two radiologists evaluated the traceability of all measurable airway points of the trachea and RMB using a three-point scale. Results: It was judged that the software satisfactorily traced airway points throughout the dynamic ventilation CT (mean score, 2.64 at the trachea and 2.84 at the RMB). From the maximum inspiratory frame to the maximum expiratory frame, the cross-sectional luminal area of the trachea decreased 17.7% and that of the RMB 29.0%, whereas the WA% of the trachea increased 6.6% and that of the RMB 11.1%. Conclusion: It is feasible to measure airway dimensions automatically at designated points on dynamic ventilation CT using research software. This technique can be applied to various airway and obstructive diseases. Keywords: computed tomography, dynamic ventilation CT, airway, luminal area, wall area percent, COPD

We investigate geometric configurations of α ( 4 He nucleus) clusters in the second J π = 2 + state of 12 C, which has been discussed as a rotational band member of the second 0 + state, the Hoyle state. The ground and excited 0 + and 2 + states are described by a three- α cluster model. The three-body Schrödinger equation with orthogonality conditions is accurately solved by the stochastic variational method with correlated Gaussian basis functions. To analyse the structure of these resonant states in a convenient form, we introduce a confining potential. The two-body density distributions together with the spectroscopic information clarify the structure of these states. We find that main configurations of both the second 0 + and 2 + states are acute-angled triangle shapes originating from the 8 Be( 0 + ) + α configuration. However, the 8 Be + α components in the second 2 + state become approximately 2/3 because the 8 Be subsystem is hard to excite, indicating that the state is not an ideal rigid rotational band member of the Hoyle state. [ABSTRACT FROM AUTHOR]