Objective To investigate the optimal distance between upper and lower target volumes and their correlated planning parameters by analyzing the dose distribution in the abutment regions during total body irradiation ( TBI) using helical tomotherapy. Methods A total of 10 patients with acute leukemia and with a height around 120 cm were enrolled. All patients were scanned by a Siemens simulation computerized tomography (CT) at a slice thickness of 5 mm. A lead wire was placed 10. 0 cm above the patella as a marker of the separation boundary for the upper and lower target volumes. The delineations of target volumes and organs at risk ( OARs ) were performed in the Varian Eclipse 13. 5 workstation with targets shrunk beyond the separation boundary at different distances. After contours and CT images were transferred to HT workstation, treatment plans were designed with different field width (FW, 5. 0 cm/2. 5 cm/1. 0 cm) and pitch values (0. 430/0. 287) at a modulation factor of 1. 8. All the plans were optimized with a dose calculation grid of 0. 195 cm × 0. 195 cm and identical planning parameters. The correlation between treatment planning parameters and targets shrunk distances were investigated by analyzing the dose distributions in the abutment area. Results The study demonstrated that the dose distributions in the abutment area were influenced only by the field width parameters: when the gap distance between the upper and lower targets was 5. 0 cm, the optimal FW is 5. 0 cm;Similarly when the gap distances were 2. 0 cm and 1. 0 cm, and the optimal FW 2. 5 cm and 1. 0 cm, respectively. In another words, the dose distribution of the abutment region was optimal when the target gap distance was equal to FW. Pitch values did not affect the quality of dose distribution in the abutment region and the overall treatment time ratio. Overall treatment time was inversely related to the FW. Conclusions Consistent target distance and FW is helpful to improve the dose homogeneity in the abutment area during TBI with HT. Appropriate planning parameters is critical to balance the treatment efficacy and efficiency.

Objective To systematically explore the traditional Chinese medicine(TCM)common symptoms,syndrome elements,clinical syndrome differentiation,and medication rules of coronary microvascular disease(CMVD),and to provide a reference for quantitative criteria of clinical differentiation of CMVD,specification of the diagnosis and efficacy evaluation of TCM clinical syndrome,and guidance of clinical medication.Methods The databases including CNKI,Wanfang,VIP,and SinoMed were searched for research papers on the treatment of CMVD by TCM published from database inception to May 16,2023.Relevant information of the included literature was extracted and the database was established.Then,the frequency statistics of symptoms,syndrome elements,syndrome types and Chinese medicinals were carried out.Latent structural models were constructed using Latern 5.0 and Rstudio softwares respectively for comprehensive clustering and association rule analysis,so as to explore the symptom characteristics,syndrome elements distribution,common syndromes and medication rules for TCM treatment of CMVD.Results A total of 107 literature were included,involving 36 syndromes,17 syndrome elements,121 symptoms and 143 Chinese medicinals.It was speculated that the main syndrome element of CMVD was blood stasis,followed by qi deficiency,qi stagnation,phlegm turbidity,yin deficiency and yang deficiency.The main type of syndrome was qi deficiency and blood stasis,followed by heart blood stasis obstruction,qi stagnation and blood stasis,phlegm blended with stasis,qi-yin deficiency,etc..The main medicinals were Chuanxiong Rhizoma,Salviae Miltiorrhizae Radix et Rhizoma,Angelica Sinensis Radix and Astragali Radix.The medicinals used in the treatment of CMVD were classified as blood-activating and stasis-resolving drugs,deficiency-tonifying drugs,qi-regulating drugs in terms of their efficacy.Conclusion The location of CMVD is in heart,and related to liver and kidney.The syndrome of CMVD is deficiency in origin and excess in superficiality.Blood stasis runs through the development of the disease.The treatment is mainly to activate blood circulation and remove stasis,activate meridians and relieve pain,which should be supplemented with the therapies of tonifying and invigorating qi,soothing the liver and regulating qi,dispelling phlegm and dissipating masses according to the patients'syndromes.