[A comparison of ventilation/perfusion single photon emission CT and CT pulmonary angiography for diagnosis of pulmonary embolism].

OBJECTIVE: To assess the diagnostic accuracy of ventilation/perfusion (V/Q) single photon emission CT (SPECT) as compared to computed tomographic pulmonary angiography (CTPA) for pulmonary embolism (PE). METHODS: In this prospective multicenter study, 111 patients in whom acute or sub-acute PE was clinically confirmed or suspected were enrolled. The patients underwent one-day method V/Q lung scan (including SPECT and planar imaging) within 3 days before and after completion of CTPA. The European Association of Nuclear Medicine (EANM) guidelines for ventilation/perfusion scintigraphy (2009) reference was used as the evaluation criteria of V/Q SPECT imaging. The refined modified prospective investigation of pulmonary embolism diagnosis (RM-PIOPED) criteria was used for evaluation of planar imaging. According to the direct and indirect signs of PE, the imaging of CTPA was evaluated. All patients were followed for at least 6 months. A diagnosis was finally made by consensus of respiratory physicians, radiologists and nuclear medicine physicians based on the clinical data, laboratory tests, imaging features and follow-up results. The difference among diagnostic methods was evaluated for significance using chi-square test. The receiver operator characteristic (ROC) curve was drawn according to the results of the 3 diagnostic tests. The area under ROC curve (AUC) was calculated and compared. P < 0.05 was considered statistically significant. RESULTS: Among the 111 patients, PE was confirmed in 80, and excluded in 31. The diagnostic sensitivity/specificity/accuracy of V/Q SPECT, planar imaging, and CTPA were 85.9%/93.5%/88.1%, 75.7%/92.9%/81.4%, and 85.5%/90.0%/86.8%, respectively. By ROC curve analysis, the AUC values of V/Q SPECT, planar imaging and CTPA were 0.898, 0.838, and 0.877, respectively; with 95% confidence intervals [CI] 0.831 to 0.966, 0.759 to 0.917, and 0.801 to 0.954, respectively. The area of the fitted smooth ROC curve was statistically significant (P < 0.05) as compared with the area under the reference line. CONCLUSION: The results indicate that SPECT V/Q imaging is superior to V/Q planar scan and CTPA in the diagnosis of PE.

Chinese multi-center study of lung scintigraphy and CT pulmonary angiography for the diagnosis of pulmonary embolism.

To evaluate diagnostic value of the PISA-PED and PIOPED II criteria for lung scintigraphy and compare it with CT pulmonary angiography (CTPA) for the detection of pulmonary embolism (PE). Five hundred and forty-four consecutive patients with suspected PE were enrolled. All patients underwent lung ventilation/perfusion (V/P) scan, chest radiography, and CTPA. Two readers used the PIOPED II criteria, and 2 used the PISA-PED criteria for the interpretation of lung scintigraphy. CTPA scans were interpreted by two experienced radiologists. Lung scintigraphy and CTPA were categorized as PE present, absent or non-diagnostic. PE was present in 321 of 544 patients. Using PIOPED II criteria, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 85.1, 82.5, 88.1, and 78.4% respectively for V/P scan. Using PISA-PED criteria, sensitivity, specificity, PPV, and NPV were 86.0, 81.2, 86.8, and 80.1% respectively, and none was non-diagnostic. Sensitivity, specificity, PPV, and NPV were 81.7, 93.4, 94.9, and 77.3%, respectively for CTPA. PISA-PED interpretation has similar diagnostic accuracy to PIOPED II interpretation, does not have non-diagnostic scan, with lower cost and radiation, thus should be considered as a choice for patients with suspected PE.

Application of 99mTc-pertechnetate scintigraphy to microvascular autologous transplantation of the submandibular gland in patients with severe keratoconjunctivitis sicca.

UNLABELLED: Our objective was to evaluate the role of (99m)Tc-pertechnetate scintigraphy on microvascular autologous transplantation of the submandibular gland in patients with severe keratoconjunctivitis sicca (KCS). METHODS: (99m)Tc-Pertechnetate scintigraphy was performed on 106 patients with severe KCS. The patients were examined before surgery and at 1 wk and 3 mo afterward using a standardized protocol that included static scintigrams, time-activity curves, and delayed scintigrams to check the function and secretion of the major salivary glands. The scintigraphic findings were assessed visually. When possible, the scintigraphic findings were compared with the clinical appearance of the transplanted gland. RESULTS: The function of all 4 major salivary glands was almost completely lost in 10 patients, indicating that these patients were not suitable for transplantation. The other 96 patients were treated by autologous transplantation of the submandibular gland. In 14 patients, the function of the major salivary glands was below normal. One patient's scintigram, obtained on the second day after surgery, showed no uptake of (99m)Tc-pertechnetate in the transplanted gland. Surgical exploration showed embolism of the artery of the transplanted gland. Scintigraphy was performed 1 wk after surgery in 90 patients. There was no uptake of (99m)Tc-pertechnetate in the temporal region in 8 patients, indicating that the glands were not revascularized. Scintigraphy showed obvious uptake of (99m)Tc-pertechnetate in the temporal region of the other 82 patients, indicating that the transplanted glands were viable. At more than 3 mo after surgery, scintigraphy was again performed on 30 patients. Scintigraphy after a 120-min delay showed that (99m)Tc-pertechnetate drained into the orbit through the duct of the transplanted gland in 26 patients. However, no secretion into the orbit was found in 4 patients, indicating obstruction of the duct. CONCLUSION: Scintigraphy plays an important role in microvascular autologous transplantation of the submandibular gland in patients with severe KCS. Scintigraphy can be used to select patients and donor glands, to evaluate the viability of the graft, and to check the patency of Wharton's duct of the transplanted gland.

[Diagnostic value of adenosine (99m)Tc-MIBI myocardial perfusion imaging for detecting coronary artery disease].

OBJECTIVE: The aim of this study was to assess the accuracy of adenosine (99m)Tc-MIBI myocardial perfusion SPECT for the diagnosis of coronary artery disease. METHODS: A total of 89 patients [mean age (57 +/- 9) years,62 men, 27 women] were included in this study. Adenosine was infused intravenously at a rate of 140 microg.kg(-1).min(-1) for 6 minutes. At the end of 3 minute of adenosine infusion, 925MBq of (99m)Tc-MIBI was injected intravenously. SPECT myocardial imaging acquisition was obtained 1 hour after adenosine infusion. Coronary angiography was performed in all patients. RESULTS: Thirty-one patients had significant coronary artery stenosis and 58 had normal coronary angiography. Adenosine myocardial perfusion imaging was abnormal in twenty-two out of the 31 patients with significant coronary artery stenosis (sensitivity, 71%). Fifty-three out of the 58 patients with normal angiography had a normal adenosine myocardial perfusion imaging (specificity, 91%). The positive predictive value and negative predictive value of adenosine (99m)Tc-MIBI myocardial perfusion imaging for detection of coronary artery disease was 81% and 84% respectively. CONCLUSION: Adenosine myocardial perfusion imaging is probably an accurate method for detecting coronary artery disease.