Alberts Ian L, Xue Song, Sari Hasan, Cavinato Lara, Prenosil George, Afshar-Oromieh Ali, Mingels Clemens, Shi Kuangyu, Caobelli Federico, Rahmim Arman, Pyka Thomas, Rominger Axel
Molecular Imaging and Therapy, BC Cancer - Vancouver, 600 West 10th Ave, Vancouver, BC, V5Z 1H5, Canada.
Department of Nuclear Medicine, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland.
Eur J Nucl Med Mol Imaging. 2025 Feb;52(3):1004-1016. doi: 10.1007/s00259-024-06921-5. Epub 2024 Oct 31.
To assess the influence of long-axial field-of-view (LAFOV) PET/CT systems on radiomics feature reliability, to assess the suitability for short-duration or low-activity acquisitions for textural feature analysis and to investigate the influence of acceptance angle.
34 patients were analysed: twelve patients underwent oncological 2-[18F]-FDG PET/CT, fourteen [18F]PSMA-1007 and eight [68Ga]Ga-DOTATOC. Data were obtained using a 106 cm LAFOV system for 10 min. Sinograms were generated from list-mode data corresponding to scan durations of 2, 5, 10, 20, 30, 60, 120, 240, 360 and 600s using both standard (minimum ring difference MRD 85 crystals) and maximum acceptance angles (MRD 322). Target lesions were segmented and radiomics features were calculated. To assess feature correlation, Pearson's product-moment correlation coefficient (PPMCC) was calculated with respect to the full duration acquisition for MRD 85 and 322 respectively. The number of features with excellent (r > 0.9), moderate (r > 0.7 and < 0.9) and poor (r ≤ 0.7) correlation was compared as a measure of feature stability. Intra-class heterogeneity was assessed by means of the quartile coefficient of dispersion.
As expected, PPMCC improved with acquisition time for all features. By 240s almost all features showed at least moderate agreement with the full count (C100%) data, and by 360s almost all showed excellent agreement. Compared to standard-axial field of view (SAFOV) equivalent scans, fewer features showed moderate or poor agreement, and this was most pronounced for [68Ga]Ga-DOTATOC. Data obtained at C100% at MRD 322 were better able to capture between-patient heterogeneities.
The improved feature reliability at longer acquisition times and higher MRD demonstrate the advantages of high sensitivity LAFOV systems for reproducible and low-noise data. High fidelity between MRD 85 and MRD 322 was seen at all scan durations > 2s. When contrasted with data comparable to a simulated SAFOV acquisition, full-count and full-MRD data were better able to capture underlying feature heterogeneities.
评估长轴视野（LAFOV）PET/CT系统对影像组学特征可靠性的影响，评估其对短时间或低活度采集用于纹理特征分析的适用性，并研究接受角的影响。
对34例患者进行分析：12例患者接受肿瘤学2-[18F]-FDG PET/CT检查，14例接受[18F]PSMA-1007检查，8例接受[68Ga]Ga-DOTATOC检查。使用106 cm LAFOV系统采集10分钟的数据。利用列表模式数据生成对应于2、5、10、20、30、60、120、240、360和600秒扫描时长的正弦图，采用标准（最小环差MRD 85晶体）和最大接受角（MRD 322）。对靶病变进行分割并计算影像组学特征。为评估特征相关性，分别针对MRD 85和MRD 322相对于全时长采集计算Pearson积矩相关系数（PPMCC）。比较具有优秀（r＞0.9）、中等（r＞0.7且＜0.9）和较差（r≤0.7）相关性的特征数量，以此作为特征稳定性的衡量指标。通过四分位离散系数评估类内异质性。
正如预期，所有特征的PPMCC均随采集时间而改善。到240秒时，几乎所有特征与全计数（C100%）数据至少具有中等一致性，到360秒时几乎所有特征都具有优秀一致性。与标准轴视野（SAFOV）等效扫描相比，表现出中等或较差一致性的特征较少，这在[68Ga]Ga-DOTATOC检查中最为明显。在MRD 322时C100%获取的数据更能捕捉患者间的异质性。
较长采集时间和较高MRD时特征可靠性的提高证明了高灵敏度LAFOV系统在获取可重复和低噪声数据方面的优势。在所有扫描时长＞2秒时，MRD 85和MRD 322之间均呈现高保真度。与模拟SAFOV采集的可比数据相比，全计数和全MRD数据更能捕捉潜在的特征异质性。
