【作者】 崔厦；

【导师】 王峻；

【作者基本信息】 山西医科大学 ， 影像医学与核医学， 2012， 硕士

【摘要】 目的：探讨宝石CT对冠状动脉粥样硬化斑块的显示能力、检查的安全性及在临床应用中的价值。方法：对2011年6月—2011年11月期间在我院临床诊断为冠心病的56例患者，按临床症状分为稳定性心绞痛(stable angina pectoris, SAP)组和急性冠脉综合征(acutecoronary syndromes, ACS)组。此56例患者均行宝石CT冠状动脉造影，对于心率≤65次/min患者采用前瞻性心电门控扫描，对于心率>65次/min患者采用回顾性心电门控扫描。经心脏后处理工作站对所得冠脉图像进行后处理。对CTCA图像上每个节段（按美国心脏协会AHA15节段分法）进行斑块的类型和斑块重构特点的分析。斑块分为：钙化斑块（1型）、混合斑块（以钙化为主）（2型）、混合斑块（以软斑块为主）（3型）、和软斑块（4型）。斑块重构分为正性重构和负性重构。对两组患者冠状动脉的狭窄程度进行评价，狭窄程度分为轻度（<50%）、中度（50%～75%）、重度狭窄（75%～99%）、完全闭塞（>99%）四级。对两组患者的斑块类型、斑块重构情况、冠脉狭窄程度进行比较。对两组患者所接受的辐射剂量进行计算和分析。结果:1. 56例患者中，SAP组患者共24例,共检出斑块172个，其中钙化斑块133个、混合斑块（以钙化为主）20个、混合斑块（以软斑块为主）4个、软斑块15个；ACS组患者32例，共检出钙化斑块89个，混合斑块（以钙化为主）6个、混合斑块（以软斑块为主）21个、软斑块67个。SAP组以钙化斑块和混合斑块（以钙化为主）为主，ACS组以软斑块和混合斑块（以软斑块为主）为主。不同类型的冠心病患者斑块的构成比差异有统计学意义（P＜0.05）,软斑块和混合斑块（以软斑块为主）与冠心病危险性有相关性。2.两组患者斑块重构间差异有统计学意义（P<0.05），ACS组以正性重构为主，SAP组以负性重构为主。3.两组患者冠脉狭窄程度间差异无统计学意义（P>0.05）。4.在56例患者中，35例扫描时采用了前瞻性心电门控技术，患者所接受的平均有效剂量为4.15±0.43mSv；21例扫描时采用了回顾性心电门控，患者所接受的平均有效剂量为9.46±1.07mSv。两组差别有统计学意义（P<0.001），且前门控组较后门控组辐射剂量降低了56.13%。结论:宝石CT可通过测量斑块的CT值、分析斑块的重构情况等来区分软斑块和钙化斑块，以判别斑块的稳定性，从而指导临床治疗。同时宝石CT探测器等的更新使扫描时患者所接受的辐射剂量大大降低。可作为评价冠心病危险程度的一种便捷、无创性检查技术，用于指导冠心病的临床诊断及预后随访的评估。更多还原

【Abstract】 Objective: To explore the capability and clinical value of Gemstone Spectral CT coronaryangiography in inspecting plaque in coronary artery.Methods: 56 patients who diagnosed coronary artery disease from Jun 2011 to November2011 in our hospital were divided into 2 groups according to clinical symptoms：stable anginapectoris group(SAP) and acute coronary syndrome group(ACS). All patients undergoneGemstone Spectral CT coronary angiography examination. The patients whose heart rate wasslow were taken prospective ECG gating axial scan and the patients whose heart rate was toofast were taken retrospective ECG gating helical scan. Plaque types and remodeling wasanalyzed on CTCA images on a per-segment basis(15-segment AHA classification). Plaquetypes were classified as calcified (type1), mixed(predominantly calcified ) (type2),mixed(predominantly non-calcified ), (type3), and non-calcified (type4). Plaques remodeling isdivided into positive remodeling and negative remodeling. To evaluate the coronary arterystenosis degree of the two groups of patients ’.The coronary artery stenosis degree is dividedinto 4 levels: mild(<50%), medium(50%~75%), severe narrow(75%~99%)，and block>99%。Analyze and compare plaque types, plaque remodeling and the degree of coronary arterystenosis. Calculate and analyze the patients ’ radiation dose.Results:1. In the 56 patients, SAP group contains 24 patients, ACS group contains 32 patients. 172plaques were detected on CTA in SAP group, 141 were calcified plaques, 12 were mixedplaque(predominantly calcified)，3 were mixed plaques(predominantly non-calcified), and theother 16 were non-calcified Plaques. 183 plaques were detected on CTA in ACS group, 89 werecalcified plaques, 6 were mixed plaques(predominantly calcified), 21 were mixed plaques(predominantly non-calcified), and the other 67 were non-calcified Plaques. The calcifiedplaques and mixed plaques（predominantly calcified）predominated in SAP group, whereas thenon-calcified plaques and mixed plaques (predominantly non-calcified) predominated in ACSgroup. The difference of plaque types between SAP group and ACS group had statisticalsignificance (P<0.05). Non-calcified plaque and mixed plaque（predominantly non-calcified）andcoronary heart disease risk has a significant correlation(P＜0.05).2. The difference of plaque remodeling between two groups had statistical significance(P<0.05). Positive remodeling predominated in ACS group, whereas negative remodeling predominated in ACS group.3. There was no statistical significant difference of the degree of coronary artery stenosisbetween two groups (P<0.05).4. In the 56 patients, 35 patients were taken prospective ECG gating axial scan , the averageED was 4.15±0.43 mSv. The other 21 patients were taken retrospective ECG gating helical scan,the average ED was 9.46±1.07 mSv. ED decreased by 56.13% in research group compared withthat of control group.Conclusions: Gemstone Spectral CT can identify soft and hard plaque through measuringthe CT value of the plaques, analyzing the situation of plaque remodeling and calcificationfeature. It can determine plaque stability, and thus guide clinical treatment. Gemstone SpectralCT can reduces the radiation dose greatly. It’s an convenient, noninvasive test technology.更多还原