New method for measuring right–left shunt fraction by quantitative analysis using SPECT/CT images

IF 2.5 Q2 RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING

Radiography Pub Date : 2025-05-09 DOI:10.1016/j.radi.2025.102973

Y. Nojima , Y. Yamazaki , S. Sato

{"title":"New method for measuring right–left shunt fraction by quantitative analysis using SPECT/CT images","authors":"Y. Nojima , Y. Yamazaki , S. Sato","doi":"10.1016/j.radi.2025.102973","DOIUrl":null,"url":null,"abstract":"<div><h3>Introduction</h3><div>We devised a quantitative method for measuring the right–left shunt fraction using SPECT/CT images.</div></div><div><h3>Methods</h3><div>In this study, 43 patients at our hospital underwent pulmonary perfusion scintigraphy with <sup>99m</sup>Tc-macroaggregated albumin. The lung radioactivity dose was calculated via quantitative analysis, and the lung uptake proportion (%) of the total dose was calculated. The right–left shunt fraction was calculated by subtracting the lung uptake proportion from the total dose (100 %), and the results was evaluated by comparing the right–left shunt fraction measured using the quantitative method with the results obtained using whole-body planar imaging (W.B.).</div></div><div><h3>Results</h3><div>In cases without a shunt, no significant difference in measurement results was observed between the two methods (<em>p</em> = 0.55). Conversely, when a shunt was present, the shunt fraction was 19.0 % ± 6.0 % for the W.B. method and 29.1 % ± 10.2 % for the quantitative method, with the difference being statistically significant (<em>p</em> < 0.05). Moreover, the quantitative method demonstrated an area under the receiver operating characteristic curve of 0.948 and an accuracy of 93.0 % when employing a threshold of 19 %–22 %.</div></div><div><h3>Conclusion</h3><div>When shunts were present, the quantitative method showed a significantly higher shunt fraction than the W.B. method. However, an accuracy of >90 % could be obtained by setting the threshold range to 19 %–22 %, indicating that the quantitative method is useful for diagnosis.</div></div><div><h3>Implications for practice</h3><div>Improving the accuracy of shunt fraction measurement using quantitative methods, it will be possible to assess the severity of right-to-left shunts and evaluate treatment outcomes. In addition, this method can be used to evaluate a right-left shunt even when it is difficult to obtain a whole-body image and is expected to be applied clinically.</div></div>","PeriodicalId":47416,"journal":{"name":"Radiography","volume":"31 4","pages":"Article 102973"},"PeriodicalIF":2.5000,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Radiography","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1078817425001178","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING","Score":null,"Total":0}

引用次数: 0

Abstract

Introduction

We devised a quantitative method for measuring the right–left shunt fraction using SPECT/CT images.

Methods

In this study, 43 patients at our hospital underwent pulmonary perfusion scintigraphy with ^99mTc-macroaggregated albumin. The lung radioactivity dose was calculated via quantitative analysis, and the lung uptake proportion (%) of the total dose was calculated. The right–left shunt fraction was calculated by subtracting the lung uptake proportion from the total dose (100 %), and the results was evaluated by comparing the right–left shunt fraction measured using the quantitative method with the results obtained using whole-body planar imaging (W.B.).

Results

In cases without a shunt, no significant difference in measurement results was observed between the two methods (p = 0.55). Conversely, when a shunt was present, the shunt fraction was 19.0 % ± 6.0 % for the W.B. method and 29.1 % ± 10.2 % for the quantitative method, with the difference being statistically significant (p < 0.05). Moreover, the quantitative method demonstrated an area under the receiver operating characteristic curve of 0.948 and an accuracy of 93.0 % when employing a threshold of 19 %–22 %.

Conclusion

When shunts were present, the quantitative method showed a significantly higher shunt fraction than the W.B. method. However, an accuracy of >90 % could be obtained by setting the threshold range to 19 %–22 %, indicating that the quantitative method is useful for diagnosis.

Implications for practice

Improving the accuracy of shunt fraction measurement using quantitative methods, it will be possible to assess the severity of right-to-left shunts and evaluate treatment outcomes. In addition, this method can be used to evaluate a right-left shunt even when it is difficult to obtain a whole-body image and is expected to be applied clinically.

查看原文本刊更多论文

利用SPECT/CT图像定量分析测量左右分流分数的新方法

我们设计了一种利用SPECT/CT图像定量测量左右分流分数的方法。方法对我院43例患者行99mtc大聚集白蛋白肺灌注显像。通过定量分析计算肺放射性剂量，并计算总剂量的肺吸收比例（%）。用总剂量（100%）减去肺摄取比例计算左右分流分数，并将定量方法测得的左右分流分数与全身平面成像（W.B.）结果进行比较，评价结果。结果在未分流的情况下，两种方法的测量结果无显著差异（p = 0.55）。相反，当存在分流器时，W.B.法的分流率为19.0%±6.0%，定量法的分流率为29.1%±10.2%，差异有统计学意义(p <；0.05)。此外，当阈值为19% ~ 22%时，该方法在受试者工作特征曲线下的面积为0.948，准确度为93.0%。结论当有分流管存在时，定量法的分流率明显高于常规法。然而，通过将阈值范围设置为19% - 22%，可以获得>； 90%的准确度，表明定量方法对诊断是有用的。实践意义使用定量方法提高分流分数测量的准确性，将有可能评估右至左分流的严重程度和评估治疗结果。此外，即使难以获得全身图像，该方法也可用于评估右-左分流，有望在临床上应用。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Radiography RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING-

CiteScore

4.70

自引率

34.60%

发文量

169

审稿时长

63 days

期刊介绍： Radiography is an International, English language, peer-reviewed journal of diagnostic imaging and radiation therapy. Radiography is the official professional journal of the College of Radiographers and is published quarterly. Radiography aims to publish the highest quality material, both clinical and scientific, on all aspects of diagnostic imaging and radiation therapy and oncology.