LONG-TERM INTRAVENOUS CALCITRIOL IN SECONDARY HYPERPARATHYROIDISM: THE ROLE OF TECHNETIUM-99M-MIBI SCINTIGRAPHY IN PREDICTING THE RESPONSE TO TREATMENT

Background: Despite the effectiveness of intravenous calcitriol in suppressing parathyroid hormone secretion in patients with uremic hyperparathyroidism, 50% of the patients remain refractory to this treatment. There are conflicting reports regarding the factors that can predict the response to treatment. Technetium-99m-MIBI scintigraphy was found to be correlated with functional activity of the parathyroid gland. Methods: We, retrospectively, evaluated 16 chronic hemodialysis patients, who were maintained on i.v. calcitriol for 36 months or longer, and who had MIBI scan either at the start of, or within the first 6 months of starting calcitriol. Nine patients had a positive uptake (+ve group), and 7 patients had a negative uptake (?ve group). All patients had an elevated iPTH (iPTH>300 pg/ml) at the start of treatment. Results: The percentage reduction of iPTH in the (?ve) and the (+ve) groups was 65% versus 45% at 12 months, and 65% versus 10% at 36 months respectively. In long-term follow-up of 36 months, all the patients in the (?ve) group responded to calcitriol; while 8 of the 9 patients (89%) in the (+ve) group didn’t respond. The difference in response between the 2 groups was statistically significant (p ≤ 0.001). Conclusion: We conclude that MIBI scan is a reliable technique in predicting the response to treatment with i.v. calcitriol in patients with secondary hyperparathyroidism.     

乳腺肿块99Tcm-MIBI双时相断层显像与X线钼靶对照研究

目的：分析比较99Tcm-甲氧基异丁基异腈（MIBI）双时相断层显像与钼靶X线摄影法对乳腺肿块的临床诊断价值。方法：对93例女性乳腺肿块患者术前1周行99Tcm-MIBI双时相断层和X线钼靶摄影检查，以术后病理结果为金标准，判断以上2种方法在乳腺癌早期诊断中的灵敏性、特异性、准确性、阳性预测值及阴性预测值。结果：①99Tcm-MIBI乳腺双时相断层显像示：良性病变早期和延迟相T/NT比值为2.08±2.85和1.69±3.05，两者有显著性差异（P<0.05）；乳腺癌早期和延迟相T/NT比值为5.00±4.34和6.79±11.94，两者无显著性差异（P>0.05）。②99Tcm-MIBI乳腺肿块双时相断层显像诊断乳腺癌的敏感性为97.1%，特异性为94.8%，准确性为95.7%，阳性预测值为91.9%，阴性预测值为98.2%；X线钼靶诊断乳腺癌的敏感性为82.9%，特异性为70.7%，准确性为75.3%，阳性预测值为63.0%，阴性预测值为87.2%；2种方法对乳腺癌的诊断效能有显著性差异（P<0.05）。结论：99Tcm-MIBI双时相断层显像对乳腺癌的诊断效能优于X线钼靶摄影法。99Tcm-MIBI乳腺双时相断层显像是一种高灵敏性和特异性的乳腺癌检查方法，对鉴别乳腺良恶性病变有较高的临床价值。     

99mTcN-NOET双时相SPECT探测肺癌纵隔淋巴结转移的临床价值

目的 探讨99mTcN-NOET双时相SPECT探测肺癌纵隔淋巴结转移(MLM)的价值.方法 29例经X线检查示肺部阴影疑肺癌的患者术前1周内进行99mTcN-NOET SPECT早期、延迟胸部断层显像和CT检查,所有病例检查前均未经放、化疗和手术治疗.根据术后病理结果分组,MLM组(G1)11例,共34处MLM;无MLM组(G2)18例.99mTcN-NOET图像根据纵隔内淋巴结区是否有异常浓聚,判断是否有淋巴结转移.半定量分析采用计算机感兴趣区(ROI)技术,计算肿瘤与正常组织(ROI1/ROI2)放射性比值即摄取比值(T/N).采用重复测量方差分析进行各组的ER、DR、RI%差异的分析,P<0.05 有统计学意义.结果 ①Gl中NOET早期阳性显像72.7%(8/11);G2中77.8%(14/18)的患者阴性显像.NOET延迟阳性显像45.4%(5/11);G2中88.9%(16/18)的患者阴性显像.而CT结果显示有54.5%(6/11)纵隔淋巴结转移.G2中83.3%(15/18)的患者显示阴性.99mTcmN-NOET早期显像诊断MLM的灵敏度、特异性和准确性分别为72.7%、77.8%、75.9%,延迟显像分别为45.5%、88.9%、72.7%;CT检查分别为54.5%、83.3%、72.4%.②G1的ER为1.26±0.11,DR为1.38±0.15;G2的ER为1.28±0.17,DR为1.43±0.22,两组DR均高于ER(P<0.001).两组ER、DR和RI%间的差别均无统计学意义(P>0.05).结论 99mTcN-NOET双时相SPECT可以用于探测肺癌纵隔淋巴结是否转移,其灵敏度及特异性与常规CT没有差别.肺癌患者进行99mTcN-NOET显像时的半定量指标与MLM无关,并且随着时间的延长,肺癌患者无论有无MLM,肿瘤清除NOET均较对侧正常肺组织缓慢.     

99m Tc-Sestamibi SPECT is a Useful Technique for Viability Detection. Results of a Comparison with NH 3 /FDG PET

Objective - Assessment of myocardial viability by 99m Tc-Sestamibi Single Photon Emission Computerized Tomography (SPECT) has been suggested as a more readily available and cheaper alternative to Positron Emission Tomography (PET) with 13 N-ammonia (NH 3 ) and 18 F-fluoro-deoxy-glucose (FDG). We hypothesized that a semi-quantitative evaluation by SPECT could delineate myocardial viability with an acceptable concordance to PET. Design - Fifty patients (age 57 &#45 7 years; ejection fraction 28 &#45 8%), with ischemic cardiomyopathy, underwent SPECT and PET imaging in random order. Viability by SPECT was defined as a defect size <50% of the segment area, or a defect representing &#83 50% of the segment but with a mean activity &#83 50% of peak activity. PET viability was defined as a perfusion score >2 and FDG score &#104 2 (five-point scale, 0 = normal, 4 = absent activity). Results - By segmental comparison to PET, SPECT yielded a sensitivity and specificity of 87% and 82% for detection of viable myocardium. The positive and negative predictive values were 96% and 58%, respectively. Conclusion - In patients with severe ischemic cardiomyopathy 99m Tc-Sestamibi SPECT can delineate viable myocardium with an acceptable segmental concordance to NH 3 /FDG PET.     

Usefulness of color doppler sonography and 99m Tc-RBC scintigraphy for preoperative diagnosis of a venous malformation of the small intestine in a 2-year-old child

Venous malformations of the small intestine are rare in children, and the preoperative diagnosis of a venous malformation in the small bowel can be very difficult. We report the case of a 2-year-old girl with a solitary cavernous venous malformation of the small intestine that caused gastrointestinal bleeding and anemia and review the usefulness of the combination of color Doppler sonography and 99m Tc-RBC scintigraphy for the diagnosis of venous malformation of the small intestine.     

Efficient lung scintigraphy

Lung scintigraphy is a first‐choice method to diagnose lung embolism. The clinical routine in most centres is a perfusion study complemented with a ventilation study when judged necessary. We describe a routine with ventilation scintigraphy preceding perfusion scintigraphy, which is completed within one hour. Furthermore, the data acquired allow the determination of lung clearance of the tracer ^99mTc‐DTPA (diethylene triamine penta‐acetate) used for the ventilation scintigraphy. An aerosol generator charged once a day with ^99mTc‐DTPA solution is used for all inhalations during the day. Inhalation is monitored with a counter and interrupted when the count rate corresponds to about 20 MBq. The ventilation imaging starts and ends with posterior projections. This allows calculation of lung clearance of ^99mTc‐DTPA. Perfusion scintigraphy is performed in a standard fashion with 100 MBq of ^99mTc‐MAA (macro‐aggregated albumin). The ventilation study was considered to give some diagnostic information in the majority of the patients. The clearance determination allows detection of inflammatory lung disease. The background activity caused by the ventilation study comprised only 13% of the activity in the perfusion scintigraphy and did not significantly interfere with interpretation of the perfusion scan. The cost for the investigation is low because of the rational system for aerosol administration and the short time for a complete study.     

局部动态法核素显像诊断下肢深静脉血栓的临床研究

目的：探讨局部动态法放射性核素显像（rdRNV)诊断下肢深静脉血栓的价值。方法：利用SPECT对297例可疑下肢深静脉血栓患者进行^99mTc-MAA rdRNV检查。检查：rdRNV诊断中央型下肢深静脉血栓及周围型下肢深静脉血栓的灵敏度分别为97．1％、87．5％，特异性分别为95．0％、89．3％。结论：rdRNV简便、无创、短期内可重复进行，是一种可靠的诊断下肢深静脉血栓方法。     

运动心肌灌注显像对可疑或确诊冠心病患者预后的判断价值

目的探讨运动心肌灌注显像对可疑或确诊冠心病患者预后的判断价值。方法对116例可疑或确诊冠心病患者行运动试验和心肌灌注显像,并进行心脏事件随访。结果得到随访资料106例,平均随访(25±8)个月,共发生心脏事件11例,单因素分析显示,年龄、陈旧性心肌梗死史、运动高峰心率、从静息到运动高峰的心率变化、运动高峰收缩压、从静息到运动高峰的收缩压变化、异常心肌显像、心肌灌注缺损数目和缺血容积率(IVR)的大小是预测心脏事件发生的有价值的危险因素。多因素逐步Lo-gistic回归分析显示,IVR的大小是心脏事件发生的最有价值的预测因子,IVR≥25%时心脏事件发生的危险性明显升高(相对危险度5.9,P<0.005);尤其当心肌灌注显像正常时,IVR<25%发生心脏事件的危险性极低。结论运动心肌灌注显像可作为预测可疑或确诊冠心病患者发生心脏事件的无创性检查方法;根据心肌灌注显像时IVR的大小可有效区分高危和低危患者。     

(99m)Tc-EC与(99m)Tc-DTPA肾显像特征的比较

目的探讨~(99m)Tc-EC与~(99m)Tc-DTPA肾显像结果的差异。方法共分为3组,即肾功能正常组(15人)、肾功能轻～中度受损组(37人,53侧病变肾)和肾功能重～极重度受损组(27,41侧病变肾)。用常规剂量的~(99m)Tc-EC和99mTc-DTPA分次进行肾显像,得出肾血流功能图像、肾图,并求出肾放射性摄取高峰时间(Tmax)、半排时间(T1/2)、相对肾脏指数(RI)、有效肾血浆流量(ERPF)和肾小球滤过率(GFR)。结果①在正常组中,99mTc-DTPA的T1/2要大于99mTc-EC,差异显著(P<0.0001),Tmax和RI差异不显著。②在肾功能轻～中度受损组中,99mTc-DTPA的Tmax要小于99mTc-EC,差异显著(P<0.05),T1/2和RI差异不显著。③在肾功能重～极重度受损组中,99mTc-DTPA的RI要小于99mTc-EC,差异显著(P<0.0001),Tmax差异不显著。④肾功能受损时,99mTc-DTPA的功能图像和肾图差于99mTc-EC,肾功能受损越重,差别越明显。结论①在同一生理或病理情况下99mTc-EC和99mTc-DTPA的肾显像结果有差异,99mTc-EC肾显像的图像质量优于99mTc-DTPA。②肾显像时,如不要求得出GFR,肾显像剂99mTc-EC为优选。     

MR imaging of cervical carcinoma: comparison among T2-weighted,dynamic, and postcontrast T1-weighted images with histopathological correlation

Background: To identify the reasons for misdiagnosis of the degree of stromal invasion by uterine cervical cancer with various magnetic resonance sequences. Methods: T2-weighted, dynamic, and postcontrast T1-weighted images were obtained in the sagittal plane in 20 patients with uterine cervical cancer. After evaluating these sequences for the degree of stromal invasion, histologic specimens were directly correlated with these images. Results: The degree of stromal invasion was correctly diagnosed in 15 of the 20 cases on T2-weighted images, in 12 on dynamic images, and in eight on postcontrast T1-weighted images. All misdiagnoses were due to overestimation. Histologically, peritumoral stroma showed inflammation or edema in two patients, whereas no histological abnormality was found in the other patients. A hyperintense rim, i.e., a peritumoral enhanced ring-shaped structure, was observed on the enhanced images of five patients. The hyperintense rim corresponded to the periphery of the tumor in three patients and to the cervical stroma in two patients. Conclusion: T2-weighted images permitted the most accurate evaluation of stromal invasion by uterine tumors. Overdiagnosis may be due to an abnormal intensity of the cervical stroma, which was observed more frequently on dynamic and postcontrast T1-weighted images than on T2-weighted images. Received: 10 November 1995/Accepted after revision: 13 March 1996