Department of Radiology, Bichat Claude-Bernard Hospital, APHP, 46 rue Henri Huchard, F-75018, Paris, France.
Department of Nuclear Medicine, Institut Gustave Roussy, 114 rue Edouard Vaillant, 94805, Villejuif Cédex, France.
Eur Radiol. 2021 Oct;31(10):7332-7341. doi: 10.1007/s00330-021-07862-5. Epub 2021 Apr 15.
The wide-volume mode, available on wide-area detector row CTs, has the advantage of reducing exposure time and radiation dose. It is infrequently used for lung diseases. The purpose of this study is to compare image quality and radiation dose of wide-volume chest CT to those of standard helical CT in the setting of interstitial lung diseases.
Retrospective monocentric study including 50 consecutive patients referred for follow-up or screening of interstitial lung diseases, requiring prone scan, acquired with the wide-volume mode, in addition to the routine supine scan, acquired with the helical mode. The optimal collimation in wide-volume mode (320 × 0.5mm or 240 × 0.5mm) was chosen according to the length of the thorax. Wide-volume acquisitions were compared to helical acquisitions for radiation dose (CTDI, DLP) and image quality, including analysis of normal structures, lesions, overall image quality, and artifacts (Wilcoxon signed-rank test).
Median CTDI and DLP with wide volumes (3.1 mGy and 94.6 mGy·cm) were significantly reduced (p < 0.0001) as compared to helical mode (3.7mGy and 122.1 mGy·cm), leading to a median 21% and 32% relative reduction of CTDI and DLP, respectively. Image noise and quality were not significantly different between the two modes. Misalignment artifact at the junction of two volumes was occasionally seen in the wide-volume scans and, when present, did not impair the diagnostic quality in the majority of cases.
Wide-volume mode allows 32% radiation dose reduction compared to the standard helical mode and could be used routinely for diagnosis and follow-up of interstitial lung diseases.
• Retrospective monocentric study showed that wide-volume scan mode reduces radiation dose by 32% in comparison to helical mode for chest CT in the setting of interstitial lung diseases. • Mild misalignment may be observed at the junction between volumes with the wide-volume mode, without decrease of image quality in the majority of cases and without impairing diagnostic quality. • Wide-volume mode could be used routinely for the diagnosis and follow-up of interstitial lung diseases.
宽体模式可用于宽探测器 CT ，具有减少曝光时间和辐射剂量的优势。但在肺部疾病中很少使用。本研究旨在比较间质性肺疾病患者中宽体容积 CT 与标准螺旋 CT 的图像质量和辐射剂量。
回顾性单中心研究纳入 50 例连续患者，因间质性肺疾病随访或筛查需要俯卧位扫描，采用宽体模式，此外还采用螺旋模式进行常规仰卧位扫描。根据胸部长度选择宽体模式（320×0.5mm 或 240×0.5mm）的最佳准直。将宽体采集与螺旋采集进行比较，比较内容包括辐射剂量（CTDI、DLP）和图像质量，包括正常结构、病变、整体图像质量和伪影的分析（Wilcoxon 符号秩检验）。
与螺旋模式（3.7mGy 和 122.1 mGy·cm）相比，宽体积（3.1 mGy 和 94.6 mGy·cm）的 CTDI 和 DLP 显著降低（p<0.0001），导致 CTDI 和 DLP 分别降低 21%和 32%的相对减少。两种模式的图像噪声和质量没有显著差异。在宽体积扫描中偶尔会在两个体积的交界处看到错位伪影，但在大多数情况下，这并不会影响诊断质量。
与标准螺旋模式相比，宽体积模式可将辐射剂量减少 32%，可常规用于间质性肺疾病的诊断和随访。
回顾性单中心研究表明，与螺旋模式相比，宽体扫描模式可将间质性肺疾病患者的胸部 CT 辐射剂量降低 32%。
宽体模式在体积交界处可能会出现轻度错位，但在大多数情况下不会降低图像质量，也不会影响诊断质量。
宽体模式可常规用于间质性肺疾病的诊断和随访。
