Discordance between dipyridamole stress technetium-99m tetrofosmin single photon emission computed tomography and coronary angiography in patients with Kawasaki disease

Kawasaki disease (KD) is an acute vasculitis syndrome of unknown etiology that mainly affects the coronary arteries. The purpose of this study was to assess the agreement between dipyridamole stress technetium-99m tetrofosmin (Tc-TF) myocardial perfusion single photon emission computed tomography (SPECT) and coronary angiography in these patients. Twenty-nine children with KD were included in this study. All of the 29 children also received dipyridamole stress Tc-TF myocardial perfusion SPECT within 1 month of their coronary angiographic studies. The results showed that (1) 89.7% of children had negative coronary angiographic findings without significant coronary stenoses, and 10.3% of children had positive coronary angiographic findings with significant coronary stenosis; (2) 44.8% of children had negative Tc-TF myocardial perfusion SPECT findings without abnormal myocardial perfusion, and 55.2% of children had positive Tc-TF myocardial perfusion SPECT findings with abnormal myocardial perfusion; (3) 44.8% of children had both normal coronary angiographic and Tc-TF myocardial perfusion SPECT findings, and 10.3% of children had both abnormal coronary angiographic and Tc-TF myocardial perfusion SPECT findings; and (4) There was no significant agreement between coronary angiographic and Tc-TF myocardial perfusion SPECT findings. We concluded that poor agreement exists between coronary angiographic and Tc-TF myocardial perfusion SPECT findings with coronary stenoses and abnormal myocardial perfusion in children with KD.     

Diagnostic accuracy of myocardial perfusion imaging with single photon emission computed tomography and positron emission tomography: a comparison with coronary angiography

Objective The aim of this study was to compare the diagnostic accuracy of myocardial perfusion imaging (MPI) by positron emission tomography (PET) with the diagnostic accuracy of MPI by single photon emission computed tomography (SPECT) in two comparable patient cohorts, using coronary angiography (CA) as the standard of reference. Methods A “SPECT-group” of 80 patients (15 female, 65 male; mean age 60 ± 9 years) and a “PET-group” of 70 patients (14 female, 56 male; mean age 57 ± 10 years) underwent a one day stress/rest examination either with attenuation-corrected ¹³N-ammonia PET or attenuation-corrected ²⁰¹TlCl SPECT or ^99mTc-hexakis-methoxy-isobutyl-isonitril (MIBI) SPECT. PET and SPECT results were semiquantitatively graded using a 6-segment heart model. All patients underwent CA, and stenoses were graded as a diameter reduction ≥50%. Results Coronary findings between both groups did not significantly differ at CA. For the SPECT-group overall sensitivity and specificity for localisation of stenoses was 77% and 84%. Respective values for the PET-group were 97% and 84%. The specificity of MPI by SPECT in the detection of ischemia was 74% and 91% for MPI by PET. The diagnostic accuracy of MPI improves when the individual coronary dominance and previous coronary revascularisations are taken into account. Conclusion MPI by ¹³N-ammonia PET is more sensitive in the detection and localisation of coronary stenoses, and more specific in the detection of ischemia than MPI by ²⁰¹TlCl/^99mMIBI SPECT.     

Left ventricular cavity-to-myocardium count ratio in exercise and resting technetium-99m-tetrofosmin SPECT: correlation with left ventricular function

The aim of this study was to assess the value of the cavity-to-myocardium count ratio (C/M ratio) calculated in exercise and resting technetium-99m (Tc-99m) tetrofosmin single photon emission computed tomography (SPECT) images to identify patients with depressed exercise and resting left ventricular ejection fraction (LVEF). We studied 60 patients with recent coronary artery diseases (CAD) undergoing first-pass ventriculography to calculate LVEF and myocardial perfusion SPECT imaging to calculate left ventricular C/M ratios. The group A of 30 CAD patients with higher LVEF (40%) had significant higher C/M ratios than the group B of 30 CAD patients with abnormal LVEF (<40%) during exercise and rest. However, C/M ratios between exercise and rest did not differ significantly in the both groups A and B. There is significant correlation between exercise/rest LVEF and exercise/rest C/M ratios. Tc-99m tetrofosmin C/M ratios calculated SPECT perfusion images are useful parameters in identifying patients with depressed LVEF in CAD patients.     

Adenosine myocardial perfusion single photon emission computed tomographic stress testing 24-72 h after uncomplicated myocardial infarction

Safety of performing adenosine myocardial perfusion stress testing as early as 24 h after acute uncomplicated myocardial infarction is not known. We evaluated 31 (14 females and 17 males, average age 72, range 46–89 years) consecutive patients with uncomplicated myocardial infarction, who underwent adenosine myocardial perfusion stress imaging, 24–72 h after infarction for risk stratification. Adenosine was infused at a rate of 140 g/kg/min for 6 min. Twenty patients were presented with non-ST-elevation myocardial infarction. Eleven patients were admitted with acute ST-elevation myocardial infarction. Patients were monitored for signs of complication during and immediately after the stress test. The average time from admission to performance of stress tests was 51 ± 19 h, ranging from the minimum of 24 h to maximum 72 h. No complications related to adenosine infusion were detected. In conclusion, our data suggest that a further large study of early adenosine myocardial perfusion SPECT imaging may be safe in a carefully selected group of patients after uncomplicated myocardial infarction.     

Cerebral hemodynamic patterns with technetium Tc 99m exametazime single photon emission computed tomography and transcranial Doppler sonography: a validation study using visual stimulation.

OBJECTIVE: To assess whether a correlation between perfusion changes to visual stimulus on the bilateral occipital areas and blood flow velocity changes to visual stimulus in both posterior cerebral arteries is present. METHODS: Nine right-handed healthy subjects (4 women and 5 men; mean +/- SD age, 58.0 +/- 5.6 years) were included in the study. Visual stimulation was performed in room light with the subject's eyes open and looking around versus eyes closed as the stimulus-off condition. The blood flow velocities were recorded using transcranial Doppler sonography, and the regional cerebral blood flow measurements were recorded with the use of technetium Tc 99m exametazime and a single photon emission computed tomographic gamma camera system. Individual reactivity was defined as a relative increase of blood flow velocity and perfusion, which were calculated as percentage changes of baseline values. RESULTS: Visual stimuli produced a marked increase of blood flow velocity in both posterior cerebral arteries (35.2 +/- 2.3 cm/s; P < .001) without a significant side-to-side difference in all subjects as well as a marked increase of perfusion on both occipital areas (24.9 +/- 4.8 cm/s; P < .01). Moreover, there was a positive correlation between blood flow velocity changes and perfusion changes on both sides (r = 0.833; P < .01). CONCLUSIONS: The use of bilateral simultaneous Doppler recordings by means of a flow velocity averaging algorithm to a specific stimulus allows quantitative assessment of blood flow responses, and simple visual stimuli can be applied for different disorders to assess the vasomotor regulation that may result in measurable abnormal cerebral flow regulation even when clinically stabilized.     

门控心肌显像在测定左心室射血分数中的应用

目的:应用单光子发射计算机体层摄影(SPECT)技术同时测定不同采集条件下左心室射血分数(LVEF)值,并与超声LVEF值比较,研究其一致性和相关性。方法:选择172例受试者,利用SPECT共行门控显像技术,用99mTc-MIBI作为示踪剂,同时将心动周期设定8和16等份,在一次采集中得到两种条件的LVEF值,并与1周时间所得超声LVEF值作比较,研究门控心肌显像在LVEF测定中的影响因素,以及与常规超声法有无相关性。结果:统计分析显示,心动周期分成8和16等份所得的LVEF值大小是不同的,后者LVEF值较大,但两种方法所得结果存在相关关系。另一方面,SPECT所得的LVEF值均较超声心动图(UCG)所得值大,但与UCG所得结果具有很好一致性。结论:门控心肌显像在心肌活力判断时,利用共行显像技术可同时得到LVEF等心功能参数,其LVEF大小与超声结果有很大相关性,但其值存在显著差异,其正常参考范围尚需进一步研究。     

短暂性全面遗忘症3例局部脑血流显像观察2年随访

目的探讨短暂性全面遗忘症(TGA)的发生与局部脑血流(rCBF)改变的关系。方法对3例临床诊断为TGA患者行单光子发射计算机体层摄影(SPECT)rCBF显像检查。结果2例患者SPECT显像示左海马区血流灌注减低,1例示双侧额叶血流灌注减少。3例患者随访24个月,均无再次遗忘发作,复查SPECT显像示血流灌注正常。结论TGA的发生可能与额叶及海马局部血流灌注减低有关。     

常规超声心动图、心电图、动态心电图及核素心肌灌注断层显像对冠心病诊断的对比研究

目的对比分析常规超声心动图(UCG)、心电图(ECG)、动态心电图(Holter)及核素心肌灌注断层显像(SPECT)对冠心病的诊断价值。方法回顾性分析120例冠心病患者的UCG、ECG、Holter及SPECT检查结果,并与冠状动脉造影(CAG)检查结果作对照。结果 120例患者中,CAG检查98例患者为冠心病,UCG显示82例患者室壁节段运动异常,ECG显示68例患者ST-T段改变,Holter显示74患者例呈阳性,SPECT显示90例患者显像异常。UCG、ECG、Holter及SPECT诊断冠状病的敏感性和特异性分别为79.59%、60.20%、65.31%、83.67%和81.82%、59.09%、54.54%、63.64%。结论 UCG的敏感性略低于SPECT,但特异性明显高于其他方法,对冠心病的诊断有较高的准确性,值得临床的广泛应用。     

~(99m)Tc-MIBI SPECT-CT显像在纵隔内异位甲状旁腺诊治中的应用价值

目的分析99mTc-甲氧基异丁基异腈(MIBI)单光子发射计算机断层显像(SPECT)-CT显像在纵隔内异位甲状旁腺诊治中的应用价值。方法以2013年8月至2014年2月北京世纪坛医院收治的100例继发性甲状旁腺功能亢进症(SHPT)患者为研究对象,所有患者均采用99mTc-MIBI双时相法显像、平面和断层显像及同机CT成像,分析纵隔内异常放射性浓聚灶融合图像,以及肿瘤与对侧正常组织(T/NT)放射性比值同全段甲状旁腺激素(iPTH)、手术病理结果的关系。结果 100例患者中出现纵隔内异位甲状旁腺2例(2.0%),其中1例于显像前给予甲状旁腺切除术,术后全段甲状旁腺激素(iPTH)再次升高;另1例给予药物治疗,2例患者术后SPECT-CT显像均显示异位甲状旁腺显像,定位于胸锁关节。平面和断层显像及同机CT成像显示,甲状旁腺的最高T/NT放射性比值与显像前iPTH水平呈正相关(r=0.419,P0.05);T/NT放射性比值的升高幅度与其对应手术切除的甲状旁腺体积呈正相关(r=0.376,P0.05)。采用CT及SPECT-CT显像时,异位甲状旁腺的敏感性优于常位甲状旁腺,而两者的阳性数、自由门静脉压(FPP)、假阳性数比较差异无统计学意义(P0.05)。结论99mTc-MIBI SPECT-CT显像能够有效地融合解剖图像和功能图像,对SHPT的诊断具备较高的特异性、灵敏性及准确性,同时可对病灶进行准确定位,提高手术效率,使手术达到令人满意的效果。     

Real-time perfusion adenosine stress echocardiography versus myocardial perfusion adenosine scintigraphy for the detection of myocardial ischaemia in patients with stable coronary artery disease

BACKGROUND: Real-time perfusion (RTP) contrast echocardiography using low mechanical index power modulation technique allows for simultaneous myocardial perfusion and wall motion analysis. RTP-adenosine stress echocardiography (ASE) could be an alternative to dobutamine-atropine stress echocardiography; more tolerable for the patients and possibly similarly accurate. We aimed to evaluate RTP-ASE for the detection of myocardial ischaemia, compared to 99mTc-sestamibi single-photon emission computed tomography (SPECT). METHODS: Patients with suspected coronary artery disease, admitted to SPECT evaluation, were prospectively invited to participate. Patients underwent RTP imaging (SONOS 5500) using infusion of Sonovue (Bracco, Milano, Italy) before and during ASE. Two separate readers performed off-line analysis of myocardial perfusion and wall motion by RTP-ASE. A perfusion defect was the principal marker of ischaemia. Wall motion assessment was used to evaluate ischaemia in segments with perfusion artefacts. Each segment was attributed to one of the three main coronary vessel areas of interest: the left anterior descending (LAD); the left circumflex (LCx) and the right posterior descending (RPD). Normal SPECT at stress was judged normal at rest. RESULTS: In 33 patients, 99 coronary territories were analysed by SPECT and RTP-ASE. SPECT showed evidence of ischaemia in 9 of 33 patients. For the detection of ischaemia, the overall level of agreement between RTP-ASE and SPECT was 92% in all segments. The level of agreement was 88% in LAD, 97% in LCx and 91% in RPD segments. CONCLUSION: Real-time perfusion-adenosine stress echocardiography using power modulation could be an accurate and feasible tool for evaluation of ischaemia in patients with suspected coronary artery disease. The results from this study need confirmation by a study of a larger patient sample.     

Bone mineral density and single photon emission computed tomography changes after total knee arthroplasty: a 2-year follow-up study

Dual X-ray absorptionmetry (DXA) provides a highly reproducible method for quantitative analysis and monitoring periprosthetic bone mineral density (BMD) after total knee arthroplasty (TKA). Single photon emission computed tomography (SPECT) with bone avid radiopharmaceuticals reflects bone metabolic activity and circulation. We combined information from DXA and SPECT to assess the evaluation of the dynamic balance between BMD and bone turnover. Sixteen patients underwent serial DXA (Lunar Expert XL) and 99mTc-methylene diphosphonate SPECT measurements until 2 years after TKA. A rapid bone loss, up to 25.5%, was detected in femur during the first six postoperative months. However, tibial periprosthetic BMD remained close to baseline. There was a significant correlation between 12-month SPECT uptake and preceding BMD change in medial tibia (r = 0.5, P = 0.044). At 12 months, SPECT uptakes in the operated knee were notably higher compared with those of the control knee. SPECT uptakes showed statistically significant decreases from 12 months to 24 months, while SPECT uptake in the control knee remained stable. In tibia, the results are more complex; referring that increased bone remodelling is continuing below the tibial tray. Furthermore, femoral diaphyseal uptake remained elevated, while corresponding tibial uptake had levelled off at 2 years. Increased SPECT uptake during the first 2 years after uncomplicated TKA results most likely from normal postoperative bone remodelling. Levelling of SPECT uptake may indicate a new balance between bone loss and regain.     

Feasibility of continuous venous infusion of SonoVue for qualitative assessment of reversible coronary perfusion defects in stress myocardial contrast echocardiography

OBJECTIVE: To study the feasibility of continuous intravenous SonoVue contrast echocardiography for qualitative assessment of reversible myocardial perfusion in dipyridamole stress tests. METHODS: Eleven patients (10 male and 1 female, mean age 66 years) with a history of chest pain and a clinical indication for stress sestamibi single photon emission computed tomography (SPECT) underwent concurrent SonoVue 99mTc myocardial contrast echocardiography (MCE). RESULTS: Of the total 176 segments obtained, 53 (30%) were regarded as indeterminate, 39 (22%) as discordant, and 84 (48%) as concordant between MCE and SPECT imaging. Two patients had abnormal SPECT results. The overall feasibility and specificity of MCE were 70 and 74%, respectively. The concordant (p = 0.59) and discordant (p = 0.55) segments were comparable with either MCE technique. However, continuous low-mechanical-index imaging produced fewer indeterminate segments (17 segments, 32%) than intermittent harmonic B-mode imaging (36 segments, 68%) (p = 0.04). Significantly more indeterminate segments were found in the left anterior descending artery territory. However, the overall concordance was similar (p = 0.5) in all three coronary artery territories. The concordance and discordance rates at different left ventricular levels (i.e., basal, mid, and apical) were similar (p = 0.50 and 0.08, respectively). CONCLUSION: Continuous-infusion SonoVue contrast echocardiography is feasible, with high specificity, for detecting myocardial perfusion defects as assessed by dipyridamole SPECT.     

Relationship between exercise-induced ST segmental depression and myocardial ischemia assessed by technetium-99m tetrofosmin SPECT imaging in patients with inferior Q wave myocardial infarction

Background: ST segment depression (STD) is a standard electrocardiographic sign of myocardial ischemia. Although STD may represent reciprocal changes in patients with previous myocardial infarction, studies of reciprocal changes during exercise testing are scarce. Methods: From December 1999 to December 2000, 160 patients (119 males, 41 females, mean age 54 ± 8 years), undergoing maximal or symptom-limited exercise treadmill test (Bruce-protocol), myocardial perfusion scintigraphy using technetium-99m tetrofosmin single photon emission computed tomography (SPECT) imaging, within 30 days of an uncomplicated inferior Q wave myocardial infarction. The location of STD at the electrocardiogram (ECG) was defined as anterior (V1-4), high lateral (I, aVL), and lateral (V5-6). Ischemia was defined as reversible perfusion abnormalities. Results: STD occurred in anterior leads in 29 patients (18.1%), in the lateral leads in 41 patients (25.6%), in the high lateral leads in 20 patients (12.5%). In 70 patients (43.8%) no significant STD occurred during the exercise test. ST segment elevation occurred in 28 patients (17.5%) in inferior leads. High lateral STD was associated with inferior ST elevation in 16 patients (80%), whereas only eight patients (19.5%) with lateral STD and nine patients (31%) with anterior STD were associated with inferior ST elevation. Ischemia was detected in 63 of 90 patients (70%) with and in 10 of 70 patients (14.3%) without STD (p < 0.0001). Patients with high lateral STD had a higher prevalence of fixed perfusion defects in the inferior wall (95 vs. 27.8%) and in posterolateral wall (75 vs. 18.9%) compared with other patients (p = 0.003 and 0.002, respectively). Ischemia was more prevalent in patients with lateral STD than without ( 87.8 vs. 14.3%, p < 0.0001). Conclusion: In patients with inferior Q wave, the presence of exercise-induced STD in lateral and anterior leads appears to be a sign of myocardial ischemia, and may require invasive evaluation; on the other hand, the presence of STD in high lateral leads should be recognized as a reciprocal change for ST elevation in the inferior leads, and may not be an indication for invasive evaluation.     

Single photon emission computed tomography (SPECT) with 99mTc-HMPAO (hexamethyl propylenamino oxime) in chronic paroxysmal hemicrania-a case report

The case of a 69-year-old woman with chronic paroxysmal hemicrania (CPH) is presented in whom cerebral perfusion was investigated using the flow tracer 99mTc-hexamethyl propylenamino oxime (HMPAO) and single photon emission tomography (SPECT). There was a bilateral hypoperfusion in the fronto-parietal region between attacks--without medication as well as under effective treatment with verapamil. During an attack, however, SPECT investigation showed a normal cerebral perfusion. Further investigation is required to find out whether these SPECT findings are due to primary alterations of brain perfusion in CPH or are only of epiphenomenological nature. The observed effectiveness of verapamil in the prophylactic treatment of CPH should be verified in a greater number of patients.     

Technetium-99m-labelled HL91 and technetium-99m-labelled MIBI SPECT imaging for the detection of ischaemic viable myocardium: a preliminary study

Purpose: The assessment of myocardial viability has become an important aspect of the diagnostic and prognostic work‐up of patients with coronary artery disease. Technetium‐99m labelled sestamibi (^99mTc‐MIBI) myocardial perfusion imaging may underestimate the viability of ischaemic myocardium. Technetium‐99m labelled 4,9‐diaza‐3,3,10,10‐tetramethyldodecan‐2,11‐dione dioxime (^99mTc‐HL91) is a hypoxia‐avid agent which can identify acutely ischaemic viable myocardium in a canine model using a standard gamma camera. The aim of this study was to evaluate uptake character of ischaemic viable myocardium and diagnostic performance of single‐photon emission computed tomography (SPECT) imaging by ^99mTc‐HL91 and ^99mTc‐MIBI in detecting ischaemic viable myocardium in coronary heart disease. Methods: A total of 41 patients with coronary artery disease were recruited from March 2008 to May 2009. For detecting ischaemic viable myocardium, SPECT imaging by ^99mTc‐HL91 and ^99mTc‐MIBI were performed in all patients before coronary revascularization. Six patients with single ischaemic myocardial segment received a 2‐day SEPCT/CT imaging protocol and the uptake of ^99mTc‐HL91 in ischaemic myocardium was quantitatively analysed. The remaining 35 patients received a 1‐day ^99mTc‐HL91 and ^99mTc‐MIBI SPECT imaging protocol. Resting ^99mTc‐MIBI myocardial perfusion imaging in 3–18 months after revascularization was used as the standard methodology to evaluate the myocardial viability. Results: In 41 patients, 66 ischaemic myocardial segments were proven to be viable and 12 to be necrotic by resting ^99mTc‐MIBI myocardial perfusion imaging after coronary revascularization. Furthermore, 60 viable segments with negative uptake of ^99mTc‐MIBI showed positive uptake of ^99mTc‐HL91. The remaining six viable segments and 12 necrotic segments showed both negative uptake of ^99mTc‐HL91 and ^99mTc‐MIBI. The sensitivity, specificity, accuracy, Younden Index, positive predictive value and negative predictive value for evaluating ischaemic viable myocardium were 90·9%, 100%, 92·3%, 90·9%, 100% and 66·7%, respectively. Ischaemic viable myocardium had the negative ^99mTc‐MIBI uptake and positive ^99mTc‐HL91 uptake, which demonstrated a mismatched uptake character. Quantitative analysis indicated the uptake of ^99mTc‐HL91 in viable myocardium was increasing in the first 1–3 h and remained stable at the 3–4 h after injection. Conclusion: Functional SPECT imaging with ^99mTc‐HL91 and ^99mTc‐MIBI can be used to detect the seriously ischaemic but viable myocardium with a mismatched uptake character. The uptake of ^99mTc‐HL91 in the viable myocardium reached a stable level at 3–4 h after injection.     

强迫症与抑郁症脑单光子发射计算机断层扫描对照研究

目的 探讨强迫症(OCD)、抑郁症局部脑血流量(regional eerebral blood flow,rCBF)特点.方法 应用单光子发射计算机断层扫描(single photon emission computed tomography,SPECT)技术,对首发且未经治疗的22例OCD患者、20例抑郁症患者和19例正常人于静息状态下行脑血流显像.以小脑皮质的放射性计数值为参考,对局部脑血流进行半定量分析.结果 0cD组脑灌注值(radioactivity rate,RAR)在双侧前额叶、前颞叶均高于正常组,分别为:强迫症组94.4±6.4,99.8±6.6,91.6±6.1,92.6±6.6;正常组88.1±7.3,86.9±8.9,84.0±7.2,83.4±7.2;差异均有统计学意义(均P＜0.01).抑郁症组灌注值在两侧前额叶、枕叶、扣带回及右侧前颞叶、顶叶分别为79.4±7.1,77.9± 6.3,89.5±9.7,89.2±10.2;85.1±6.4,84.3±6.3;75.4±7.5;84.1±7.5;低于正常组的灌注值:88.1±7.3,86.9±8.9;97.7±11.2,96.2±8.4,95.4±8.7;83.4±7.2;92.4±9.4;差异均有统计学意义(P＜0.01或P＜0.05).结论 与正常对照组比,0CD组的前额叶及前颞叶呈高灌注改变;抑郁症组脑血流普遍低灌注;SPECT技术可望作为二者鉴别诊断的客观依据之一.     

实时心肌超声造影多指标联合应用对冠心病诊断的临床价值

目的 探讨实时心肌超声造影(RT-MCE)多指标联合应用对冠心病诊断的临床价值.方法 人选35例患者均行常规超声心动图检查和经静脉RT-MCE,并于RT-MCE检查后2-4 d行门控单光子发射计算机断层显像(gated-SPECT)检查,所有患者均于RT-MCE检查后1周内行冠状动脉造影(CAG)检查.以CAG为金标准分为冠心病组和非冠心病组.采用Qlab软件对造影图像微泡再充盈曲线进行定量分析,求出各节段的最大微泡数量(A)、造影剂充填速度(β)及其乘积A×β值;与CAG结果对比,采用受试者曲线寻求A值、β值及A×β值对冠心病的诊断截断点;对22例冠心病患者行Gensini评分,与A值、β值及A×β值行相关分析.②Gated-SPECT图像中所有节段采用4分计分方法,计算其诊断冠心病的敏感性和特异性.③分析RT-MCE多指标联合应用观察对冠心病的诊断价值.结果 ①A值、β值及A×β值在冠心病组与非冠心病组间差异有统计学意义(P<0.05);RT-MCE定量指标A值、β值及A×β值分别以4.58、0.64及2.73为截断点,其诊断冠心病的敏感性分别为86.O%、80.2%和88.9%,特异性分别为84.1%、64.6%和79.9%;A值、β值及A×β值与Gensini评分间的相关系数分别为-0.79、-0.51和-O.76.②Gated-SPECT诊断冠心病的敏感性和特异性分别为84.8%和82.7%.③A与β、A与A×β及β与A×β联合诊断的敏感性增加,分别为89.1%,90.4%及96.3%.结论 RT-MCE多指标联合应用优于gated-SPECT,可提高诊断冠心病的准确性和评价冠状动脉狭窄的严重程度.     

心肌灌注显像在女性冠心病诊断中价值

目的评价心肌灌注显像对女性冠心病患者的诊断价值。方法 344例有胸痛、胸闷症状女性患者,行静息+药物负荷心肌灌注显像检测,并与冠状动脉造影结果进行对比分析。结果冠状动脉狭窄178例患者中心肌灌注显示异常者130例;冠状动脉造影无异常或不规则166例中心肌灌注显像异常50例,无异常116例;以冠状动脉造影结果为标准,心肌灌注显像对女性冠心病诊断的敏感度、特异度、阳性预测值、阴性预测值分别为73.0%,69.9%,72.2%,70.7%。结论心肌灌注显像对女性冠心病患者的诊断及是否进一步行冠状动脉造影的筛选有一定价值。     

Regional V˙A/Q˙ ratios in man using 133Xe and single photon emission computed tomography (SPECT) corrected for attenuation

We describe a technique to obtain non-invasively regional pulmonary ventilation–perfusion ratios (V˙_A/Q˙) using single photon emission computed tomography (SPECT) and continuous infusion of ¹³³Xe. Single photon transmission tomography was used for attenuation correction, for delineation of the lungs and for V˙_A/Q˙ calculations. Data are presented for six normal subjects and compared to those for two patients with moderate chronic obstructive pulmonary disease (COPD). The mean V˙_A/Q˙ for the whole lung of the normal subjects ranged from 0·49 to 0·65, group mean 0·56 ± 0·07 (1 SD), and there was no significant difference between the right and left lung. The consistently too low V˙_A/Q˙ values are related to the inability to measure regional blood volume and the low resolution of the scintillation camera, giving an under-estimation of tracer input. For the normal subjects, the dispersion of V˙_A/Q˙, as defined by the standard deviation of the individual distribution functions, ranged from 0·12 to 0·19. One of the patients was characterized by a low mean V˙_A/Q˙ of 0·35, and the other patient had a wide dispersion (SD) of V˙_A/Q˙ of 0·37. In the normal subjects, a consistent V˙_A/Q˙ gradient was found only in the ventrodorsal direction. ¹³³Xe and SPECT can be used to obtain meaningful biological information regarding ventilation/perfusion relationships of potential clinical value.