ObjectiveTo summarize the modern minimally invasive surgical treatment of hemorrhoids and related clinical research progress.MethodLiteratures on minimally invasive surgery for hemorrhoids at home and abroad in recent years were collected and reviewed.ResultsThe modern minimally invasive operation of hemorrhoids can be divided into three types. One was for bleeding symptoms to reduce blood supply of hemorrhoids artery for blood vessel block operation; the second one was for prolapse symptoms to restore anal pad anatomical position based on the mucosal resection; the third one was for pain itch symptoms to remove the proliferation of tissue mass based hemorrhoidectomy. All kinds of operations extended to different modified or combined operations. Under the premise of reasonable selection of patients, minimally invasive surgery for hemorrhoids was safe and effective.ConclusionsWith the rapid development of modern minimally invasive surgery technology and surgical instruments, the surgical treatment of hemorrhoids has been constantly innovated. Any kind of minimally invasive surgery for hemorrhoids has its specific indications and limitations. Therefore, we should pay attention to symptomatic treatment and comprehensive treatment, in order to better play the advantages of minimally invasive surgery for hemorrhoids.
Patient-specific volumetric modulated arc therapy (VMAT) quality assurance (QA) process is an important component of the implementation process of clinical radiotherapy. The tolerance limit and action limit of discrepancies between the calculated dose and the delivered radiation dose are the key parts of the VMAT QA processes as recognized by the AAPM TG-218 report, however, there is no unified standard for these two values among radiotherapy centers. In this study, based on the operational recommendations given in the AAPM TG-218 report, treatment site-specific tolerance limits and action limits of gamma pass rate in VMAT QA processes when using ArcCHECK for dose verification were established by statistical process control (SPC) methodology. The tolerance limit and action limit were calculated based on the first 25 in-control VMAT QA for each site. The individual control charts were drawn to continuously monitor the VMAT QA process with 287 VMAT plans and analyze the causes of VMAT QA out of control. The tolerance limits for brain, head and neck, abdomen and pelvic VMAT QA processes were 94.56%, 94.68%, 94.34%, and 92.97%, respectively, and the action limits were 93.82%, 92.54%, 93.23%, and 90.29%, respectively. Except for pelvic, the tolerance limits for the brain, head and neck, and abdomen were close to the universal tolerance limit of TG-218 (95%), and the action limits for all sites were higher than the universal action limit of TG-218 (90%). The out-of-control VMAT QAs were detected by the individual control chart, including one case of head and neck, two of the abdomen and two of the pelvic site. Four of them were affected by the setup error, and one was affected by the calibration of ArcCHECK. The results show that the SPC methodology can effectively monitor the IMRT/VMAT QA processes. Setting treatment site-specific tolerance limits is helpful to investigate the cause of out-of-control VMAT QA.