Objective　To synthesize and label a tumor positive imaging agent 18F-fluorouracil (FU) and the animal study on the product was also undertaken. Methods　18F-FU was synthesized and labeled. Its biodistribution analysis was done on normal and tumor bearing nude mice. PET imaging was performed on normal and tumor bearing rabbits. Results　HPLC analysis and other quality control test results guaranteed the possibility of animal study and clinical usage of 18F-FU. Biodistribution analysis and PET imaging also demonstrated a high accumulation of the tracer in tumor tissue. Conclusion　18F-FU is a kind of potential tumor positive imaging agents which can be used to assess the effects of chemotherapy.

Objective To investigate the application value of free plasma metanephrines metanephrine(MN) and normetanephrine (NM) measured with enzyme immunoassay (EIA), NM in diagnosis of pheochromocytoma. Methods Histologically confirmed pheochromocytomas (n=30) and control patients with hypertension (n=51) were enrolled in the study. Blood tests for free plasma metanephrines(MN and NM) were performed with a commercially available EIA kit and the results were compared with [3] I-metaiedobenzyl guanidine (MIBG) whole body scan findings. Results The whole body scan was positive in all pheochromocytoma patients and negative in 15 control patients with 100% accuracy. The median values in the 2 groups were 59.3 ng/L and 33.7 ng/L (Z=-2. 440, P<0.05) for MN, 652.0 ng/L and 36. 3 ng/L (Z=-6.699, P<0.001) for NM, with 96. 7% (29/30) sensitivity, 86. 3% (44/51)specificity and 90.1% (73/81) accuracy for their combination ( either or both positive). There was no significantly statistical difference when compared with 13I-MIBG whole body scan findings (100. 0% ,P >0. 05). Conclusion The results show that the EIA method may be eligible as an alternative to HPLC for plasma metanephrines determination in the identification of pheochromocytoma.

Objective:To investigate the diagnostic efficacy and clinical application value of 99Tc m-diethylene triamine pentaacetic acid (DTPA) SPECT/CT imaging in cerebrospinal fluid leakage (CSFL). Methods:A total of 23 patients (11 males, 12 females; age (44.2±15.1) years) who underwent endoscopic repair surgery for suspected CSFL in Shanghai Jiao Tong University Affiliated Sixth People′s Hospital between April 2018 and January 2020 were retrospectively reviewed. All patients performed 99Tc m-DTPA SPECT/CT imaging, paranasal sinus high resolution CT (HRCT) and MRI before surgery. The diagnostic efficacies of 3 imaging techniques were calculated according to the result of surgery regarded as the golden standard. χ2 test was used to compare the qualitative and localized diagnostic efficacies of 3 imaging techniques for CSFL. Results:Of 23 patients, 21 were finally confirmed with CSFL and 24 leak locations were identified according to the results of surgery; the other 2 patients had no obvious CSFL and no leak location was found during the operation. The sensitivity and accuracy of 99Tc m-DTPA SPECT/CT, MRI and HRCT for the diagnosis of CSFL were 100%(21/21) and 95.7%(22/23), 85.7%(18/21) and 82.6%(19/23), 76.2%(16/21) and 69.6%(16/23), respectively. The accuracy of 99Tc m-DTPA SPECT/CT, MRI and HRCT for the diagnosis of leak location was 79.2%(19/24), 50.0%(12/24) and 45.8%(11/24), respectively. There was no statistically significant difference of diagnostic efficacies for CSFL among 3 imaging techniques ( χ2 values: 0.451-3.453, all P>0.05). For leak location, the diagnostic efficacy of 99Tc m-DTPA SPECT/CT was significantly better than that of MRI and HRCT ( χ2 values: 4.463, 5.689, both P<0.05). Conclusion:99Tc m-DTPA SPECT/CT imaging shows an excellent diagnosis efficacy not only for CSFL but also for leak location, which is helpful for guiding surgery.

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