Immune function of HIFU treatment

About immune function, who observed the tumor regressed at the same time, the distant metastasis also subsided that HIFU treatment can improve the body's specific and non-specific immunity to tumors. The killing effect of tumor cells can indirectly promote the development and maturation of helper lymphocytes,piezo ceramics activate the cytotoxic effect of cytotoxic lymphocytes (CTL) on tumor cells, and promote the production of cytokines by lymphocytes. Madersbacher et al.who analyzed the prostatic specimens after HIFU treatment who found that the expression of heat shock protein in the basal secretory epithelial cells.whose surrounding of the coagulative necrotic area was significantly increased, which may be one of the important factors inducing the body's immune response. It has been found that breast cancer cells highly expressed can stimulate the proliferation of peripheral blood lymphocytes and enhance the lysis of B cells and T cells on tumor cells. 

The exact mechanism and clinical efficacy of HIFU to improve the immune function of the body remains to be further studied; (3) It can be used as part of comprehensive treatment of tumors. Hyperthermia has a sensitizing effect on radiotherapy, mainly because hyperthermia is more likely to cause heat accumulation in bloodless, hypoxic tumor cells and S-phase cells with poor blood supply, thereby destroying the effect of radiotherapy and improving the effect of radiotherapy.which reduce the dose of radiotherapy. Many chemotherapeutic drugs are insensitive to tissue cells with low blood supply and metabolic quiescent period. Hyperthermia makes up for the lack of chemotherapy, so that more tumor cells enter the proliferative cycle, ultrasound piezoelectric ceramic disc is beneficial to the better efficacy of chemotherapy drugs. other applications of HIFU combined with lipiodol arterial embolization found that the ultrasound treatment dose can be significantly reduced.

Concept of treatment area and therapeutic dose: HIFU piezoceramic transducer mainly uses the transmission of ultrasound to focus the lower energy ultrasound in vitro on deep tumor lesions in the body, killing tumor cells by transient high temperature effect and cavitation effect generated by high energy ultrasound in the focal zone. Different dose parameters can cause different degenerative necrosis of tissue, and the range of degeneration and necrosis is also called the treatment area. first found that the size and shape of coagulative necrotic tissue caused by H IFU was related to the therapeutic dose while ensuring that other physical parameters were unchanged. Ter Haar et al reported that when the irradiation time is constant, the volume of the treatment area becomes larger as the intensity of the sound increases; when the sound intensity is constant, the volume of the treatment area increases as the irradiation time increases. As the sound intensity and irradiation time increase, the more the acoustic energy absorbed by the target tissue, the more obvious the heat conduction. After measuring and comparing the volume of fresh isolated bovine liver injury,it is believed that the volume of the treatment area decreases with the increasing treatment depth (exponentially decreasing). When the treatment time of HIFU piezoceramic transducer is the same, the shape gradually changes from cone to shape. It is an ellipsoid.