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Neuroblastoma is the most common extracranial solid tumor in children. The prognosis of different stages varies greatly, and its risk staging system is completely based on imaging. Radionuclide imaging plays an important role in the diagnosis and staging of various tumors, and it is also of great significance in the early diagnosis and staging of neuroblastoma. At present, imaging agents used for neuroblastoma mainly include catecholamine receptor, glucose metabolism, somatostatin receptor, etc. This article mainly discusses the application value and research progress of these imaging agents in the diagnosis of neuroblastoma.
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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.
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The radiotheranostics allows for precise diagnosis and treatment of differentiated thyroid cancer,neuroendocrine tumors,prostate cancer and other malignant diseases through providing solutions for personalized medicine.The development of radiotheranostics owns opportunities but also confronts challenges,including developing novel radiopharmaceuticals with new targets,clinical translation,radiometry and safety assessment.The challenges and opportunities of radiotheranostics were looked in this article.
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Combining with molecular imaging,nuclear medicine gradually utilized radiopharmaceuticals with targeted radionuclide therapy for accurate diagnosis and individualized treatment of diseases,hence advancing the progresses of theranostics.The clinical research progresses of radiotheranostics in diagnosis and therapy of diseases were reviewed in this article.
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Objective:To explore the impact of different segmentation methods on differential diagnostic efficiency of 18F-FDG PET/MR radiomics to distinguish Parkinson′s disease (PD) from multiple system atrophy (MSA). Methods:From December 2017 to June 2019, 90 patients (60 with PD and 30 with MSA; 37 males, 53 females; age (55.8±9.5) years) who underwent 18F-FDG PET/MR in Union Hospital, Tongji Medical College, Huazhong University of Science and Technology were retrospectively collected. Patients were randomized to training set and validation set in a ratio of 7∶3. The bilateral putamina and caudate nuclei, as the ROIs, were segmented by automatic segmentation of brain regions based on anatomical automatic labeling (AAL) template and manual segmentation using ITK-SNAP software. A total of 1 172 radiomics features were extracted from T 1 weighted imaging (WI) and 18F-FDG PET images. The minimal redundancy maximal relevance (mRMR) and least absolute shrinkage and selection operator (LASSO) algorithm were used for features selection and radiomics signatures (Radscore) construction, with 10-fold cross-validation for preventing overfitting. The diagnostic performance of the models was assessed by ROC curve analysis, and the differences between models were calculated by Delong test. Results:There were 63 cases in training set (42 PD, 21 MSA) and 27 cases in validation set (18 PD, 9 MSA). The Radscore values were significantly different between the PD group and the MSA group in all training set and validation set of radiomics models ( 18F-FDG_Radscore and T 1WI_Radscore) based on automatic or manual segmentation methods ( z values: from -5.15 to -2.83, all P<0.05). ROC curve analysis showed that AUCs of 18F-FDG_Radscore and T 1WI_Radscore based on automatic segmentation in training and validation sets were 0.848, 0.840 and 0.892, 0.877, while AUCs were 0.900, 0.883 and 0.895, 0.870 based on manual segmentation. There were no significant differences in training and validation sets between Radiomics models based on different segmentation methods ( z values: 0.04-0.77, all P>0.05). Conclusions:The 18F-FDG PET/MR radiomics models based on different segmentation methods achieve promising diagnostic efficacy for distinguishing PD from MSA. The radiomics analysis based on automatic segmentation shows greater potential and practical value in the differential diagnosis of PD and MSA in view of the advantages including time-saving, labor-saving, and high repeatability.
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Objective:To investigate the predictive values of 18F-FDG PET/CT image feature and metabolic parameters for the malignant potential of gastrointestinal stromal tumor (GIST). Methods:From March 2014 to June 2020, the 18F-FDG PET/CT imaging and surgical pathological data of 35 patients with GIST (27 males, 8 females; age 44-84 years) from Union Hospital, Tongji Medical College, Huazhong University of Science and Technology and Zhongnan Hospital of Wuhan University were analyzed retrospectively. Patients were divided into ring-shaped uptake group and other uptake patterns group according to 18F-FDG PET/CT image feature. Fisher′s exact test was used to analyze the differences of tumor necrosis and National Institutes of Health (NIH) risk classification (short for NIH classification) between different image feature groups. Mann-Whitney U test was used to analyze the differences of SUV max , metabolic parameters at different thresholds (2.5, 40%, 50%) of SUV max (metabolic tumor volume (MTV; MTV 2.5, MTV 40%, MTV 50%) and total lesion glycolysis (TLG; TLG 2.5, TLG 40%, TLG 50%)) between different clinicopathological features (lesion location, tumor diameter, mitotic count, Ki-67, necrosis, image feature, NIH classification) groups. Spearman rank correlation analysis was used to explore the correlation between clinicopathological features and metabolic parameters. ROC curve analysis was used to distinguish NIH classification of different metabolic parameters. Delong test was used to compared differences between different AUCs. Results:Of 35 GIST patients, 11(31.4%) were ring-shaped uptake and 24(68.6%) were other uptake patterns, and the differences of necrosis (7/11 vs 12.5%(3/24); P=0.004) and NIH classification (11/11 vs 25.0%(6/24); P<0.001) between the two groups were significant. There were significant differences of metabolic parameters between different groups of tumor diameter, mitotic count, necrosis, image feature, NIH classification ( z values: from -4.70 to -2.09, all P<0.05), while there were no significant differences of Ki-67 ( z values: from -0.83 to -0.71, all P>0.05). Metabolic parameters were correlated with mitotic count, tumor diameter, necrosis, image feature and NIH classification ( rs values: 0.36-0.81, all P<0.05), while was not correlated with Ki-67 ( rs values: 0.12-0.14, all P>0.05). The differences of AUCs between SUV max and MTV 2.5, TLG 2.5, TLG 40%, TLG 50%were significant (0.752, 0.856, 0.856, 0.882, 0.886; z values: 1.96-2.12, all P<0.05). Conclusions:The NIH classification of GIST with ring-shaped uptake on 18F-FDG PET/CT is higher and more prone to necrosis. The 18F-FDG PET/CT metabolic parameters based on different thresholds of SUV max have certain significance for the prediction of NIH classification of GIST, and may be superior to SUV max.
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Presynaptic dopaminergic PET imaging is a useful method for the diagnosis of parkinsonism. Based on the expert consensus on operation and clinical application of dopamine transporter brain PET imaging technology published in 2020, this paper further recommends the relevant elements of result interpretation of presynaptic dopaminergic PET imaging.
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Objective:To investigate the diagnostic and prognostic value of 68Ga-fibroblast activation protein inhibitor (FAPI) PET for hepatobiliary malignancies. Methods:From July 2020 to February 2023, 33 patients (23 males, 10 females; age (55.4±13.5) years) with suspected or confirmed liver or biliary tract malignancies who underwent 68Ga-FAPI PET in Union Hospital, Tongji Medical College, Huazhong University of Science and Technology were retrospectively analyzed. PET images were evaluated by 3 experienced nuclear medicine physicians, and the results of biopsy or postoperative pathology, clinical and imaging follow-up were used as the gold standard. One-way analysis of variance and least significant difference t test were used to compare the differences among groups. Survival analysis was performed using Kaplan-Meier curves and the log-rank test. Results:Of 33 patients, 14 performed PET for initial diagnosis and staging, and 19 for restaging. There were 14 patients with hepatocellular carcinoma (HCC), 13 patients with cholangiocarcinoma (CCA), and 6 patients with gallbladder carcinoma (GBC). The primary tumor of HCC, CCA and GBC all showed significant 68Ga-FAPI uptake, with no statistically significant difference in SUV max among groups ( F=1.58, P=0.250). The sensitivities of 68Ga-FAPI PET for initial diagnosis and restaging of hepatobiliary malignancies were 14/14 and 15/15, respectively. Compared with conventional imaging, 68Ga-FAPI PET changed the diagnosis and staging in 29.2%(7/24) patients. The treatment strategy was changed in 30.3%(10/33) patients with malignant tumors due to 68Ga-FAPI PET findings. Follow-up showed 22 cases survived and 11 cases died, with the overall survival of 355.56(80.00, 516.97) d, and 1- and 2-year survival rates were 68.2% and 57.9%, respectively. Semi-quantitative 68Ga-FAPI PET parameters such as SUV max, target-liver ratio (TLR), and target-blood ratio (TBR) had no significant prognostic value, but the prognosis of the group without distant metastases diagnosed by 68Ga-FAPI PET was significantly better than that of the group with distant metastasis ( P=0.032). Conclusion:68Ga-FAPI PET has high sensitivity for the diagnosis of hepatobiliary malignancies, which can help guide treatment decisions and prognosis evaluation.
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Nasopharyngeal carcinoma (NPC) is one of the most common malignant tumors of the head and neck. In clinical practice, imaging examination plays an important role in the diagnosis, staging and risk assessment of NPC. However, it is difficult to distinguish the heterogeneity within the tumor, so the ability to classify and predict NPC is limited. Radiomics can extract a large amount of data from medical images for quantitative analysis, which further improves the ability of imaging features to diagnose and predict tumors. The purpose of this review is to introduce the application value of radiomics of different imaging modality such as CT, MRI and PET in differential diagnosis, predictions of treatment response, prognosis and radiotherapy complications of NPC.
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The treatment of persistent/recurrent and metastatic thyroid cancer and medullary thyroid cancer has made significant progress through the use of molecule-targeted therapy. While this approach has shown promise in improving patient outcomes and clinical symptoms, it also carries potential risks. The primary focus and challenge of targeted therapy is to optimize benefits while managing risks within predetermined thresholds. This review examines current targeted treatment practices in thyroid cancer and investigates the correlation between the timing of targeted therapy initiation and the patient benefits, aiming to lay the groundwork for subsequent research.
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Objective:To study whether Bayesian penalized likelihood (BPL) and its optimized reconstruction algorithm can improve the reconstructed image quality of low count total-body PET.Methods:Eight patients (5 males, 3 females, age (67.2±6.3) years) who underwent hybrid 18F-FDG PET/MR total-body scans at Department of Nuclear Medicine in Union Hospital, Tongji Medical College, Huazhong University of Science and Technology were collected retrospectively from January to June in 2023. Total-body PET/MR images of them were included and list-mode data were reconstructed with four methods, namely 25% counts conventional reconstruction (group 1), 100% counts conventional reconstruction (group 2), 25% counts BPL reconstruction (group 3), and 25% counts optimized BPL reconstruction (group 4). At last, 32 total-body PET images were obtained. SUV max and SUV mean in different ROIs and tumor metabolic volume (MTV) were measured. Total lesion glycolysis (TLG) and parameters of image quality including the ratio of lesion to background (L/B) and image signal-to-noise ratio (SNR) were calculated. Then the differences in all the parameters among the four groups were analyzed by repeated measures analysis of variance and Friedman test. Quantitative differences between BPL reconstruction and optimized BPL with the 100% counts conventional reconstruction were compared respectively by using the Bland-Altman (BA) plot. Results:For the inter-group comparison, except for SUV mean in the muscle ( F=0.38, P=0.767), SUV max and SUV mean in other ROIs were statistically different ( F values: 8.15-36.08, χ2=18.15, all P<0.01), as well as MTV and L/B ( χ2 values: 10.65, 13.35, P values: 0.014, 0.004), but not for TLG ( χ2=4.95, P=0.175) or SNR ( F=2.64, P=0.076). For the pairwise comparison, the differences between group 2 and group 3 were the most significant (all P<0.05). Compared with group 2, there were no significant differences for SUV max and SUV mean of the cerebellar cortex and lesions in group 4 (all P>0.05), as well as MTV and L/B (both P>0.05). In addition, compared with group 1, SUV max of liver and muscle in group 2 were decreased (both P<0.05), while there were no significant differences in group 4 (all P>0.05). BA plots showed that the differences of SUV, MTV, and TLG between group 4 and group 2 were smaller obviously than those between group 3 and group 2. Conclusion:BPL reconstruction can improve low focus detection sensitivity induced by low counts, but it will cause significant changes for PET quantification, which can be solved by optimized BPL reconstruction.
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Fibroblast activation protein(FAP)can overexpress in activated fibroblasts.In recent years,radiolabeled FAP inhibitor(FAPI)had become important new positron imaging agents in nuclear medicine following 18F-FDG,and increasingly used for non-malignant diseases.The research progresses of FAPI PET imaging for diagnosis of non-malignant diseases were reviewed in this article.
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Objective:To explore the feasibility of pretargeting technique for immunoPET with epidermal growth factor receptor (EGFR) monoclonal antibody in EGFR positive/negative tumor bearing mice.Methods:Cetuximab- Trans-cyclooctene (TCO)was obtained by modifying Cetuximab with TCO- N-hydroxysuccinimide (NHS). 2, 2′-((6-amino-1-(4, 7-bis-(carboxymethyl)-1, 4, 7-triazonan-1-yl)hexan-2-yl)azanediyl)-diacetic acid (L-NETA)was used as a chelating agent to prepare the radioligand 68Ga-L-NETA-tetrazine (Tz), then the labeling rate and in vitro stability of the product were determined. Human basal breast cancer cells MDA-MB-468 (EGFR+ ) and MDA-MB-231 (EGFR-) were cultured in vitro. In vitro experiments were performed to explore the specificity of the probe and the feasibility of pretargeting technique. Nude mice (Balb/c-nu) bearing xenografts of the above two cell lines were established. Cetuximab-TCO (50 μg) was injected into the tumor-bearing mice in advance, then 68Ga-L-NETA-Tz was injected at different time points (48, 36, 24 and 12 h), and pretargeting was realized through " click chemistry" . Small-animal PET imaging and biodistribution were performed to evaluate pharmacokinetic properties and specificity of the probe. The one-way analysis of variance was used to compare the data. Results:The 68Ga-L-NETA-Tz molecular probe was successfully prepared with the labeling yield >95%, and the radiochemical purity was >95% after 2 h. Cetuximab-TCO and 68Ga-L-NETA-Tz were added to MDA-MB-468 cells successively, and the cell uptake rate reached (0.69±0.04)% at 1 h, which demonstrated the feasibility of the pretargeting technique. PET imaging and biodistribution results showed that the best imaging results were obtained in 36 h pre-injection group, in which the tumor uptake was the highest ((0.77±0.05) percentage activity of injection dose per gram of tissue (%ID/g), 1 h) and the tumor/muscle ratio was optimal (4.67±0.46); the tumor uptake in the blocking group, the group without injecting Cetuximab-TCO, and the MDA-MB-231 group were significantly lower ((0.35±0.01), (0.39±0.05), (0.45±0.10) %ID/g; F=15.50, P=0.002). Conclusions:EGFR targeted immunoPET imaging is successfully performed in mouse models of breast cancer by injecting Cetuximab-TCO and 68Ga-L-NETA-Tz successively. It provides an effective method for immunoPET imaging of monoclonal antibodies.
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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.
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Epidermal growth factor receptor (EGFR) plays an important role in the development and occurrence of a variety of malignant tumors. Molecular targeted therapy for EGFR is in the ascendant. Molecular imaging can reveal the expression of EGFR and its mutations in vivo. The molecular probes labeled with 89Zr, 11C and 18F are used for imaging and the main research is about tyrosine kinase inhibitors labeled with 11C. PET is used to visualize EGFR expression and mutations in vivo, which can noninvasively screen patients suitable for targeting treatment and evaluate efficacy. This paper reviews the clinical researches and trials of these probes, and summarizes the clinical value of imaging methods, hoping to provide the evidence for clinical translation and application in the future.
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Multi-centre clinical trials on PET/CT brain imaging are complex to organize and require careful co-ordination and management. This article describes considerations, which are necessary when designing and starting a multi-centre clinical trial on PET/CT brain imaging, based on guidelines and multi-center clinical brain imaging studies, providing references for further studies.
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Due to the availability of 18F-FDG in PET centers, this article aims to advocate and promote the standardization of 18F-FDG PET brain imaging in dementia in order to improve the reliability, repeatability and comparison of the imaging process and results. It is also provided to guide the PET imaging operation standard and to give suggestions on image interpretation.
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PET plays an important role in diagnosis, staging, treatment response assessment, recurrence surveillance, follow-up and treatment guidance for the malignancy. Artificial intelligence is the scientific fields using computer and other advanced technologies to simulate human intelligent behaviors and critical thinking, among which machine learning and deep learning are most widely used in medicine. Available big data, the progress of computer science and computational capabilities facilitate the application of artificial intelligence in image analysis. This article reviews the current clinical application research of artificial intelligence in PET/CT imaging used for prognosis and prediction of malignant tumors, and puts forward current challenges and prospects for the future.
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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.
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Parkinson′s disease (PD) is a common neurodegenerative disease, but due to the lack of reliable biomarkers, the clinical diagnosis of PD is challenging. Molecular imaging technology is a new technology which combines molecular biology technology with modern medical imaging. In recent years, the role of molecular imaging technology in the diagnosis and differential diagnosis of PD has been supported by more and more evidences, which can provide an important basis for the early diagnosis and differential diagnosis of PD. Although the research results of molecular imaging in the diagnosis and differential diagnosis of PD are increasing, the clinical application is still insufficient. Therefore, it is necessary to understand the research status of molecular imaging technology, and explore the future development direction, in order to make more rational use of this technology and better serve the clinical practice.