PDF(Pubmed)
Abstract：
OBJECTIVE: Magnetic resonance (MR) imaging with secretin stimulation (MR-PFTs) is a non-invasive test for pancreatic exocrine function based on assessing the volume of secreted bowel fluid in vivo. Adoption of this methodology in clinical care and research is largely limited to qualitative assessment of secretion as current methods for secretory response quantification require manual thresholding and segmentation of MR images, which can be time-consuming and prone to interrater variability. We describe novel software (PFTquant) that preprocesses and thresholds MR images, performs heuristic detection of non-bowel fluid objects, and provides the user with intuitive semi-automated tools to segment and quantify bowel fluid in a fast and robust manner. We evaluate the performance of this software on a retrospective set of clinical MRIs.
METHODS: Twenty MRIs performed in children (< 18 years) were processed independently by two observers using a manual technique and using PFTquant. Interrater agreement in measured secreted fluid volume was compared using intraclass correlation coefficients, Bland-Altman difference analysis, and Dice similarity coefficients.
RESULTS: Interrater reliability of measured bowel fluid secretion using PFTquant was 0.90 (0.76-0.96 95% C.I.) with - 4.5 mL mean difference (-39.4-30.4 mL 95% limits of agreement) compared to 0.69 (0.36-0.86 95% C.I.) with - 0.9 mL mean difference (-77.3-75.5 mL 95% limits of agreement) for manual processing. Dice similarity coefficients were better using PFTquant (0.88 +/- 0.06) compared to manual processing (0.85 +/- 0.10) but not significantly (p = 0.11). Time to process was significantly (p < 0.001) faster using PFTquant (412 +/- 177 s) compared to manual processing (645 +/- 305 s).
CONCLUSIONS: Novel software provides fast, reliable quantification of secreted fluid volume in children undergoing MR-PFTs. Use of the novel software could facilitate wider adoption of quantitative MR-PFTs in clinical care and research.
METHODS: Twenty MRIs performed in children (< 18 years) were processed independently by two observers using a manual technique and using PFTquant. Interrater agreement in measured secreted fluid volume was compared using intraclass correlation coefficients, Bland-Altman difference analysis, and Dice similarity coefficients.
RESULTS: Interrater reliability of measured bowel fluid secretion using PFTquant was 0.90 (0.76-0.96 95% C.I.) with - 4.5 mL mean difference (-39.4-30.4 mL 95% limits of agreement) compared to 0.69 (0.36-0.86 95% C.I.) with - 0.9 mL mean difference (-77.3-75.5 mL 95% limits of agreement) for manual processing. Dice similarity coefficients were better using PFTquant (0.88 +/- 0.06) compared to manual processing (0.85 +/- 0.10) but not significantly (p = 0.11). Time to process was significantly (p < 0.001) faster using PFTquant (412 +/- 177 s) compared to manual processing (645 +/- 305 s).
CONCLUSIONS: Novel software provides fast, reliable quantification of secreted fluid volume in children undergoing MR-PFTs. Use of the novel software could facilitate wider adoption of quantitative MR-PFTs in clinical care and research.
摘要：
目的：促胰液素刺激磁共振（MR）成像（MR-PFTs）是一种基于体内分泌的肠液体积评估的胰腺外分泌功能的非侵入性测试。在临床护理和研究中采用这种方法在很大程度上仅限于对分泌物进行定性评估，因为当前的分泌反应量化方法需要对MR图像进行手动阈值和分割。这可能是耗时的，并且容易出现评分者之间的可变性。我们描述了对MR图像进行预处理和阈值的新颖软件（PFTquant），执行非肠液对象的启发式检测，并为用户提供直观的半自动工具，以快速和稳健的方式分割和量化肠液。我们评估了该软件在一组回顾性临床MRI上的性能。
方法：20例儿童（<18岁）的MRI由两名观察者使用手动技术和PFTquant独立处理。使用组内相关系数比较了测得的分泌液体体积的评分者之间的一致性，Bland-Altman差异分析,和骰子相似系数。
结果：使用PFTquant测量的肠液分泌的评估者间可靠性为0.90（0.76-0.9695％C.I.），平均差异为-4.5mL（-39.4-30.4mL95％一致界限），而手动处理为0.69（0.36-0.8695％C.I.），平均差异为-0.9mL（-77.3-75.5mL95％与手动处理(0.85+/-0.10)相比,使用PFTquant(0.88+/-0.06)的骰子相似性系数更好,但不显著(p=0.11)。与手动处理(645+/-305s)相比,使用PFTquant(412+/-177s)处理时间显著(p<0.001)更快。
结论：新颖的软件提供了快速，对接受MR-PFTs的儿童分泌的液体量进行可靠的定量。新软件的使用可以促进定量MR-PFTs在临床护理和研究中的更广泛采用。
方法：20例儿童（<18岁）的MRI由两名观察者使用手动技术和PFTquant独立处理。使用组内相关系数比较了测得的分泌液体体积的评分者之间的一致性，Bland-Altman差异分析,和骰子相似系数。
结果：使用PFTquant测量的肠液分泌的评估者间可靠性为0.90（0.76-0.9695％C.I.），平均差异为-4.5mL（-39.4-30.4mL95％一致界限），而手动处理为0.69（0.36-0.8695％C.I.），平均差异为-0.9mL（-77.3-75.5mL95％与手动处理(0.85+/-0.10)相比,使用PFTquant(0.88+/-0.06)的骰子相似性系数更好,但不显著(p=0.11)。与手动处理(645+/-305s)相比,使用PFTquant(412+/-177s)处理时间显著(p<0.001)更快。
结论：新颖的软件提供了快速，对接受MR-PFTs的儿童分泌的液体量进行可靠的定量。新软件的使用可以促进定量MR-PFTs在临床护理和研究中的更广泛采用。
