Objective:To compare and choose the best method for measuring metabolic tumor volume (MTV) of nasal extranodal natural killer/T-cell lymphoma (ENKTL), evaluate the prognostic value of 18F-FDG PET/CT metabolic parameters and clinical staging/scoring systems for patients with nasal ENKTL, and explore the added value of the two combinations for prognostic prediction. Methods:From January 2016 to September 2022, 44 patients (26 males, 18 females; age (47.5±13.6) years) pathologically diagnosed with nasal ENKTL who underwent 18F-FDG PET/CT imaging before treatment in Union Hospital, Tongji Medical College, Huazhong University of Science and Technology were retrospectively collected. SUV 2.5, SUV 4.0 and 41%SUV max were used as thresholds to measure MTV and total lesion glycolysis (TLG), and the consistency was analyzed by Bland-Altman analysis. The ROC curve analysis was used to compare the prognostic efficiency of different methods and determine the best method. The prognostic values of different clinical factors and clinical staging/scoring systems between groups were evaluated by corrected χ2 test. The independent factors were screened by Cox-regression model, and the combined diagnosis model was constructed by logistic regression. Results:Of 44 patients, 6(13.6%) were dead, with the overall survival (OS) of 32.05(11.77, 64.43) months, and the 2-year and 5-year OS rates of 86.6% and 82.5%, respectively. The mortality of different groups in age (≥60 and <60 years), prognostic index of natural killer cell lymphoma (PINK) score (low- and high-risk), and international prognostic index (IPI) score (low- and high-risk) were significantly different ( χ2 values: 5.02, 4.12, 3.88, all P<0.05). The consistency of MTV measured by different thresholds was good. Among them, the MTV measured by threshold of SUV 2.5 had the highest predictive efficiency with the AUC of 0.737. Multivariate analysis showed that MTV (hazard ratio ( HR)=10.488, 95% CI: 1.864-59.026, P=0.008) was the independent influencing factor of OS. By removing other factors, minimization model was obtained, including MTV and PINK score ( P values: 0.006, 0.048). The prediction model of MTV combined with PINK score improved prognostic efficacy with the AUCs of MTV, PINK score and the combination model of 0.781, 0.741 and 0.912, respectively. Conclusions:MTV measured by threshold of SUV 2.5 has better prognostic predictive value. MTV is the independent prognostic factor for OS in nasal ENKTL patients. MTV combined with PINK score has better prognostic value.

Thyroid associated ophthalmopathy (TAO) is an organ-specific autoimmune disease. TAO is clinically classified into active and inactive stage, and the accurate judgment is the key point of treatment choice. Clinical activity score (CAS) is often used for the assessment of TAO activity, which is subjective to some extent. With the development of imaging techniques, ultrasonography, CT, MRI and radionuclide imaging have gradually been applied into the diagnosis and treatment of TAO. What′s more, the imaging is an important complement to CAS from the aspects of anatomical and functional metabolism, which can better assess the activity and the therapy response of TAO. The clinical value of medical imaging in activity and treatment efficacy evaluation of TAO is reviewed in this article.

Massive open online course (MOOC), as an online teaching mode, has attracted widespread attention in the education field. It realizes the integration of online teaching and learning in medical education and brings profound changes in concepts and methods of medical education. It has proposed a new development direction for modern medical education. The first Nuclear Medicine online MOOC resource is not only a supplement to direct face-to-face courses in a special period, but also a strong support for the realization of online and offline hybrid teaching, thereby promoting the " student-centered" undergraduates′ autonomous learning ability. The students can achieve the goal of the development of learning ability. Based on the results of applying the Nuclear Medicine MOOC to the teaching of undergraduates in multiple schools, this article further explains the obvious advantages of MOOC as an online teaching resource library for students′ knowledge internalization. The foundation of the new teaching method ensures the effective implementation of the above teaching methods and provides ideas for further deepening the reform of undergraduate medical education.

Objective:To explore the significance of 99Tc m-sulfur colloid lymphoscintigraphy in the diagnosis of lower limb lymphedema after gynecological tumor surgery. Methods:The clinical data of patients with lower limb lymphedema after gynecological tumor surgery in Union Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology from May 2015 to October 2019 were retrospectively analyzed. 99Tc m-sulfur colloid lymphoscintigraphy was performed in all patients. The results of lymphatic vessel imaging, lymph node imaging and their combination in the diagnosis of lower limb lymphedema were analyzed. The diagnostic efficacy of lymphatic vessel imaging alone, lymph node imaging alone and their combination was evaluated by the receiver operating characteristic (ROC) curve and the area under the curve (AUC), and the Youden index, sensitivity and specificity were calculated. Results:Among the 100 lower limbs of 50 patients, 56 limbs had lymphedema and 44 limbs had no obvious edema. When diagnosis was based on abnormal lymphatic vessel imaging alone, among 56 lower limbs with lymphedema, lower limbs lymphatic vessel imaging was positive in 38 (67.9%) and negative in 18 (32.1%); among 44 lower limbs without obvious edema, lower limbs lymphatic vessel imaging was positive in 6 (13.6%) and negative in 38 (86.4%); the sensitivity was 67.9%, the specificity was 86.4%, and the Youden index was 0.543. When diagnosis was based on abnormal lymph node imaging alone, among 56 lower limbs with lymphedema, lower limbs lymph node imaging was positive in 42 (75.0%) and negative in 14 (25.0%); among 44 lower limbs without obvious edema, lower limbs lymph node imaging was positive in 13 (29.5%) and negative in 31 (70.5%); the sensitivity was 75.0%, the specificity was 70.5%, and the Youden index was 0.455. When diagnosis was based on the combination of lymphatic vessel imaging and lymph node imaging, among 56 lower limbs with lymphedema, lymphatic vessel imaging and lymph node imaging were positive in 48 (85.7%) and negative in 8 (14.3%); among 44 lower limbs without obvious edema, lymphatic vessel imaging and lymph node imaging were positive in 14 (31.8%) and negative in 30 (68.2%); the sensitivity was 85.7%, the specificity was 68.2%, and the Youden index was 0.539. The AUC for the combined diagnosis of lymphatic vessel imaging and lymph node imaging was 0.781, the AUC for the diagnosis of abnormal lymphatic vessel imaging was 0.771, and the AUC for the diagnosis of abnormal lymph node imaging was 0.739 (all P < 0.01). Conclusions:99Tc m-sulfur colloid lymphoscintigraphy is of great help in the diagnosis of lower limb lymphedema after operation of gynecological tumors. The combination of lymph node imaging and lymphatic vessel imaging is more effective in the diagnosis of lower limb lymphedema.

At the end of December 2019, acute respiratory infectious diseases caused by a new type of coronavirus were prevalent in Wuhan and other cities of China. Different from radiology examinations, the protocols of nuclear medical imaging examinations are complicated, in which more workplaces and staff are needed, resulting more complex management of patients and higher protection requirements. Combined with the characteristics of SPECT and PET imaging procedures, this paper puts forward some suggestions on the protective process of imaging examinations for patients with confirmed or suspected noval coronavirus infec- tion. The main purpose is to protect medical staff from virus infection, effectively reduce the risk of virus transmission during the examination process, and ensure the medical quality and safety.

At the end of December 2019, acute respiratory infectious diseases caused by a new type of coronavirus were prevalent in Wuhan and other cities of China. Different from radiology examinations, the protocols of nuclear medical imaging examinations are complicated, in which more workplaces and staff are needed, resulting more complex management of patients and higher protection requirements. Combined with the characteristics of SPECT and PET imaging procedures, this paper puts forward some suggestions on the protective process of imaging examinations for patients with confirmed or suspected novel coronavirus infection. The main purpose is to protect medical staff from virus infection, effectively reduce the risk of virus transmission during the examination process, and ensure the medical quality and safety.

Tumor microenvironment is different from the microenvironment formed by normal cells and surrounding tissues.It is composed of tumor cells,stromal cells,extracellular matrix (ECM),vasculature and various cytokines.Tumor microenvironment can promote the genesis,development,metastasis and resistance to therapy of tumor.Using PET molecular imaging to show tumor microenvironment can provide important biological information for early precise diagnosis and treatment intervention,as well as therapeutic effect evaluation and prognosis of tumor.In this paper,the main application categories and prospects of PET molecular imaging in tumor microenvironment are reviewed.

Objective To evaluate the role of calcineurin ( CaN)/nuclear factor of activated T cell cytoplasmic 4 protein ( NFATc4) signaling pathway in inflammatory responses in lung tissues of rats with ventilator-induced lung injury ( VILI) . Methods Twenty-four clean-grade healthy male Wistar rats, aged 5-8 weeks, weighing 220-250 g, were divided into 3 groups ( n=8 each) using a random number table method: control C (group C), VILI group and cyclosporine A plus VILI group (group CsA+VILI). The animals were anesthetized with pentobarbital and tracheostomized. The rats were mechanically ventilated for 6 h with the tidal volume set at 40 ml/kg and respiratory rate at 40 breaths/min to establish the model of VI-LI. The rats kept spontaneous breathing in group C. CaN specific inhibitor cyclosporine A 10 mg/kg was in-traperitoneally injected at 1 h before ventilation in group CsA+VILI. Rats were sacrificed immediately after ventilation, lung tissues were obtained and stained with hematoxylin and eosin to evaluate lung injury, broncho-alveolar lavage fluid was collected for determination of tumor necrosis factor-alpha ( TNF-α) , inter-leukin-1beta ( IL-1β) and IL-6 concentrations by enzyme-linked immunosorbent assay, and the lungs were removed for determination of the wet to dry weight ratio ( W/D ratio) , expression of intercellular adhesion molecule-1 ( ICAM-1) and vascular cell adhesion molecule-1 ( VCAM-1) ( by real-time polymerase chain reaction) , and expression of calcineurin and NFATc4 in lung tissues ( using Western blot ) . Results Compared with group C, the W/D ratio, lung injury scores and concentrations of IL-1β, IL-6 and TNF-αin BALF were significantly increased, and the expression of CaN, NFATc4, ICAM-1 mRNA and VCAM-1 mRNA was up-regulated in group VILI ( P＜0. 05) . Compared with group VILI, the W/D ratio, lung injury scores and concentrations of IL-1β, IL-6 and TNF-αin BALF were significantly decreased, and the expres-sion of CaN, NFATc4, ICAM-1 mRNA and VCAM-1 mRNA was down-regulated in group CsA+VILI ( P＜0. 05) . Conclusion CaN/NFATc4 signaling pathway mediates inflammatory responses in lung tissues of rats with VILI.

Objective To evaluate the influences of FBP and OSEM (with different iteration numbers or subset numbers) on cardiac function parameters with MPI,and to identify a suitable clinical method.Methods The MPI of 66 patients (33 males,33 females,age range: 18-77 years) from January 2012 to December 2014 were retrospectively analyzed.The imaging data was reconstructed with FBP and 5 different OSEM (4-16 subsets and 2-4 iterations) in order to evaluate if there was any difference of cardiac function parameters calculated by QGS between the different image processing methods.In addition,the results were compared with those of cardiac ultrasonography.One-way analysis of variance was used for data analysis.Results The statistical differences of LVEF,EDV,and ESV(F values: 10.73,4.89 and 5.97,all P<0.05) were found among 6 reconstructed methods.The values of LVEF were (66.14±11.12)％,(75.05±12.10)％,(70.09±11.27)％,(66.88±10.38)％,(64.97±10.25)％,and (62.58±9.84)％.Those of EDV were (77.32±27.58),(67.97±27.56),(75.10±27.89),(81.03±28.11),(84.94±29.07),and (89.98±29.71) ml,and the ESV values were (28.71±10.04),(19.71±16.51),(25.13±17.66),(29.01±18.47),(32.10±19.63),and (35.83±20.41) ml respectively.The cardiac function parameters measured by OSEM (with 2 iterations,12 subsets) were much similar to that measured by cardiac ultrasonography.Conclusion Compared with other 5 processing methods of MPI,the OSEM (with 2 iterations,12 subsets) method may be more suitable for practical clinical application.