EVOLUTION OF VIEWS ON THE DEVELOPMENT AND IMPLEMENTATION OF MODERN SURGICAL MAGNETIC INSTRUMENTS ON THE CASE OF INFLAMMATORY PENETRATING INJURIES OF THE BREAST

Summary. The arms — to analyze the evolution of the development of modern surgical instruments in gunshot wounds chest. Materials and methods. 80 cases of using a modern magnetic surgical instrument for penetrating gunshot wounds of the chest were analyzed. Intraoperatively used: a magnetic multifunctional tool for the diagnosis and removal of metallic ferromagnetic foreign bodies, a flexible device for removing ferromagnetic foreign bodies, a magnetic tool for endovideoscopic diagnosis and removal of metallic ferromagnetic foreign bodies from the abdominal and pleural cavities, a magnetic nozzle for video endoscopic surgical interventions. When removing metal foreign bodies, the following methods were used: a method for preliminary determination of the material and properties of a foreign body, a method for video endoscopic laser visualization of the internal organs of the abdominal and pleural cavities. Results. Foreign bodies of the pleural cavity were diagnosed in 80 (100 %) wounded according to СT. Ferromagnetic metal foreign bodies of a gunshot origin of the pleural cavity were removed both during thoracotomy or minithoracotomy, and during thoracoscopic surgical interventions using the method of video endoscopic laser visualization of the internal organs of the abdominal and pleural cavities. The most convenient tool was the endoscopic magnetic tool for removing foreign bodies from the pleural or abdominal cavities. A magnetic nozzle for video endoscopic surgical interventions allows navigation both in the pleural cavity and along the wound channel. Conclusions. 1. The development of a surgical magnetic instrument was phased and began with the improvement of a surgical magnetic instrument to remove ferromagnetic foreign bodies of soft tissues. 2. The improvement of the tool took place as the restrictions on the use of the existing tool were established, which was a prerequisite for the development of a new tool. 3. It is advisable to create a special set of surgical magnetic instruments for video endoscopic surgery.

Temperature-insensitive cable tension monitoring during the construction of a cable-stayed bridge with a custom-developed pulse elasto-magnetic instrument

Pulse elasto-magnetic method has numerous applications for monitoring cable tension force in cable-stayed bridges. In conventional pulse elasto-magnetic measurements, the feature parameters in frequency domain are seldom discussed. In this study, attempts are made to seek new parameters in frequency domain which are mainly influenced by cable tension force and less sensitive to temperature. A custom-developed pulse elasto-magnetic instrument is employed to conduct cable tension monitoring in the construction stage of a cable-stayed bridge. The field testing results show that only after temperature compensation, the monitoring results of the feature parameters extracted from the magnetic characteristic curve can reflect the stepped changes of cable tension force. Surprisingly, a new frequency-domain parameter, the summation of spectra amplitudes in a carefully selected frequency range, is found to be insensitive to temperature and can well reflect the stepped change behavior of cable tension force. The feasibility of this temperature-insensitive parameter for cable force measurements was verified by field test in two stay cables. The averaged value of the new parameter at each stage linearly depends on cable tension force. The findings about the new frequency-domain parameter may facilitate temperature-insensitive cable tension monitoring in cable-stayed bridge with a pulse elasto-magnetic instrument.