Automatic 3D camera positioning in cardiac computed tomography: A phantom study

IF 2.5 Q2 RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING

Radiography Pub Date : 2025-05-15 DOI:10.1016/j.radi.2025.102981

Y.H. Hadi , A. Legoff , N. Moore , M.-J. Murphy , L. Sweetman , H. Precht , A. England , M. McEntee

{"title":"Automatic 3D camera positioning in cardiac computed tomography: A phantom study","authors":"Y.H. Hadi , A. Legoff , N. Moore , M.-J. Murphy , L. Sweetman , H. Precht , A. England , M. McEntee","doi":"10.1016/j.radi.2025.102981","DOIUrl":null,"url":null,"abstract":"<div><h3>Introduction</h3><div>Cardiac computed tomography angiography (CCTA) is essential for diagnosing coronary artery disease, with accurate positioning critical for optimising image quality (IQ) and radiation exposure. Vertical misalignment can degrade IQ and increase radiation dose. Automatic 3D camera positioning systems claim to improve accuracy and reduce errors, though research on their effectiveness in CCTA remains limited. This study evaluates positioning accuracy, radiation dose, and IQ when using automatic 3D camera positioning in CCTA across scenarios.</div></div><div><h3>Methods</h3><div>This prospective phantom study utilised the Multipurpose Chest N1 Phantom (Kyoto Kagaku, Japan) across three body sizes. Positioning variations included supine versus prone, head-first versus feet-first orientations, and various body surface coverings. CT scans were undertaken on a GE Revolution Apex Elite (GE Healthcare, USA) scanner. Vertical offsets from the isocentre were measured using DoseWatch software (GE Healthcare), while radiation dose was quantified through dose-length product (DLP) and Computed Tomography Dose Index (CTDI<sub>vol</sub>). IQ was assessed by calculating the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and conspicuity index.</div></div><div><h3>Results</h3><div>Automatic 3D camera positioning achieved a mean (standard deviation) vertical offset of −1.0 (1.5) mm. Larger phantom sizes were significantly associated with increased off-centring, as indicated by Fisher's exact test (p = 0.004), and greater offsets correlated with higher radiation doses (r = 0.45, p < 0.05). IQ metrics, including SNR and CNR, decreased with increased offsets; SNR dropped from 71. to 50.9, and CNR from 0.2 to −0.6.</div></div><div><h3>Conclusion</h3><div>This study demonstrates that automated 3D camera positioning in CCTA supports radiographers by enhancing positioning accuracy, lowering radiation exposure and improving IQ. Further work should examine the impact of automatic 3D camera positioning within clinical practice.</div></div><div><h3>Implication for practice</h3><div>Automatic 3D camera positioning in CCTA will likely improve patient care and safety.</div></div>","PeriodicalId":47416,"journal":{"name":"Radiography","volume":"31 4","pages":"Article 102981"},"PeriodicalIF":2.5000,"publicationDate":"2025-05-15","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/S1078817425001257","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

Cardiac computed tomography angiography (CCTA) is essential for diagnosing coronary artery disease, with accurate positioning critical for optimising image quality (IQ) and radiation exposure. Vertical misalignment can degrade IQ and increase radiation dose. Automatic 3D camera positioning systems claim to improve accuracy and reduce errors, though research on their effectiveness in CCTA remains limited. This study evaluates positioning accuracy, radiation dose, and IQ when using automatic 3D camera positioning in CCTA across scenarios.

Methods

This prospective phantom study utilised the Multipurpose Chest N1 Phantom (Kyoto Kagaku, Japan) across three body sizes. Positioning variations included supine versus prone, head-first versus feet-first orientations, and various body surface coverings. CT scans were undertaken on a GE Revolution Apex Elite (GE Healthcare, USA) scanner. Vertical offsets from the isocentre were measured using DoseWatch software (GE Healthcare), while radiation dose was quantified through dose-length product (DLP) and Computed Tomography Dose Index (CTDI_vol). IQ was assessed by calculating the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and conspicuity index.

Results

Automatic 3D camera positioning achieved a mean (standard deviation) vertical offset of −1.0 (1.5) mm. Larger phantom sizes were significantly associated with increased off-centring, as indicated by Fisher's exact test (p = 0.004), and greater offsets correlated with higher radiation doses (r = 0.45, p < 0.05). IQ metrics, including SNR and CNR, decreased with increased offsets; SNR dropped from 71. to 50.9, and CNR from 0.2 to −0.6.

Conclusion

This study demonstrates that automated 3D camera positioning in CCTA supports radiographers by enhancing positioning accuracy, lowering radiation exposure and improving IQ. Further work should examine the impact of automatic 3D camera positioning within clinical practice.

Implication for practice

Automatic 3D camera positioning in CCTA will likely improve patient care and safety.

查看原文本刊更多论文

心脏计算机断层扫描中的自动3D相机定位：一项幻象研究

心脏计算机断层血管造影（CCTA）对于诊断冠状动脉疾病至关重要，准确定位对于优化图像质量（IQ）和辐射暴露至关重要。垂直不对准会降低智商，增加辐射剂量。自动3D相机定位系统声称可以提高精度并减少误差，尽管对其在CCTA中的有效性的研究仍然有限。本研究评估了在CCTA中使用自动3D相机定位时的定位精度、辐射剂量和IQ。方法：这项前瞻性假体研究使用了多用途胸部N1假体（Kyoto Kagaku, Japan），适用于三种体型。体位变化包括仰卧与俯卧，头先与脚先，以及不同的体表覆盖物。CT扫描在GE Revolution Apex Elite （GE Healthcare， USA）扫描仪上进行。使用DoseWatch软件（GE Healthcare）测量离等心的垂直偏移量，同时通过剂量长度积（DLP）和计算机断层扫描剂量指数（CTDIvol）量化辐射剂量。通过计算信噪比（SNR）、噪声对比比（CNR）和显著性指数来评估智商。结果自动3D相机定位的平均（标准偏差）垂直偏移为- 1.0 (1.5)mm。Fisher精确检验（p = 0.004）表明，较大的幻影尺寸与偏离中心的增加显著相关，较大的偏移与较高的辐射剂量相关(r = 0.45, p <；0.05)。IQ指标，包括SNR和CNR，随着偏移量的增加而降低；信噪比从71下降。至50.9，CNR从0.2至- 0.6。结论本研究表明，CCTA中的自动3D摄像机定位通过提高定位精度、降低辐射暴露和提高智商来支持放射技师。进一步的工作应该检查自动3D相机定位在临床实践中的影响。在CCTA中自动3D相机定位可能会改善患者的护理和安全性。

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.