Feasibility of Respiratory-gated High-pitch Spiral CT:: Free-breathing Inspiratory Image Quality

详细信息    查看全文

• 作者：Michael M. Lell ; MD^a ; ^b ; Michael Scharf ; MD^a ; Achim Eller ; MD^a ; Wolfgang Wuest ; MD^a ; Thomas Allmendinger ; PhD^c ; Florian Fuchs ; MD^d ; Stephan Achenbach ; MD^e ; Michael Uder ; MD^a ; ^b ; Matthias S. May ; MD^a ; ^b ; ^{matthias.may@uk-erlangen.de" class="auth_mail" title="E-mail the corresponding author}
• 关键词：CT ; thorax ; lung ; adults ; artifacts
• 刊名：Academic Radiology
• 出版年：2016
• 出版时间：April 2016
• 年：2016
• 卷：23
• 期：4
• 页码：406-412
• 全文大小：1560 K

文摘

This study aimed to develop and implement a respiratory-gated setup for dual-source computed tomography (CT) at high pitch to examine patients in a reproducible inspiratory phase.

Materials and Methods

Twenty-one patients underwent free-breathing respiratory-gated chest CT using a high-pitch scan mode no more than 6 months after inspiratory breath-held nongated CT, which serves as reference. Scan parameters were as follows: pitch = 3.4, 128 × 0.6 mm collimation, 0.28 s gantry rotation time, and 150 ref.mAs per tube at 120 kV. The examinations were triggered using the tidal wave provided by a respiratory-gating system as input signal. Image quality was assessed focusing on artifacts and delineation of the anatomical and pathological structures. Lung volumes were measured on both free-breathing and reference examinations.

Results

All examinations were performed without complications. Image quality was high with both protocols. Significantly less motion artifacts were recorded with the high-pitch mode compared to the reference (P = 0.02). Most of the artifacts were located in the peripheral parts of the lower lobes for the study group and in the central part of the left lower lobe for the reference. Average total lung volume was 4.5 ± 1.5 L in respiratory-gated examinations and 5.8 ± 0.9 L in examinations with breath-hold in inspiration.

Conclusions

High-pitch chest CT scanning during free breathing minimizes motion artifacts, improving image quality in patients with limited breath-holding abilities. To assure scanning in an inspiratory phase, data acquisition should be triggered with a respiratory-gating system.