Naslov
Real time transfer of live video image in parallel with volume 3D-models of the surgical field in Tele-3D-computer assisted surgery: two different approaches

Autori
Klapan Ivica

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, stručni

Izvornik
Abstract Book: 5th European Copngress of Otorhinolaryngology Head and Neck Surgery, Rodos, Greece / - Rodos, 2004

Skup
5th European Copngress of Otorhinolaryngology Head and Neck Surgery, Rodos, Greece

Mjesto i datum
Rodos, Grčka, 11.09.2004. - 16.09.2004

Vrsta sudjelovanja
Pozvano predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Real time; video image; volume rendering; 3D-models; surgical field; Tele-3D; computer assisted surgery

Sažetak
During the telesurgery, the computer with its operative field image allows the surgeon, by means of up-to-date technologies, to connect the operative instrumentarium to spatial digitalizers connected to the computer. Upon the completion of the tele-operation, the surgeon compares the preoperative and postoperative images and models of the operative field, and studies video records of the procedure itself. Using intraoperative records, animated images of the real tele-procedure performed can be designed. By means of computer records labeled coordinate shifts of 3D digitalizer during the surgery, an animated image of the course of operation in the form of journey, i.e. operative field fly-through in the real patient, can be designed. Beside otorhinolaryngology, this has also been used in other fields. The more so, in addition to educational applications, VS offers the possibility of preoperative planning in sinus surgery, and has become a very important segment in surgical training and planning of each individual surgical or telesurgical intervention, not only in the reigon of paranasal sinuses. The complex software systems allow tele-visualization of CT or MRI section in its natural course (the course of examination performed), or in an imaginary, arbitrary course. Particular images can be transferred, processed and deleted, or can be presented in animated images, as it was done during our 1st TS. Multiple series of images can be simultaneously observed in different color tables and at various magnification, with various grades of transparency, observing them as a unique 3D model system. The work with such models allows different views, shifts, cuts, separations, labeling, and animation. The series of images can be changed, or images can be generated in different projections through the volume recorded, as we have showed in our OR. Before the development of 3D spatial model, each individual image or the whole series of images have to be segmented, in order to single out the image parts of interest. Thus, separate models of bones, healthy tissue, affected tissue, and all significant anatomic entities of the operative field are developed. The complete tele-procedure planned can be developed on computer models and a series of animations describing the procedure can be produced. It has become a routine mode of action in a number of centers worldwide when necessary. Comparative analysis of 3D anatomic models with intraoperative finding, in any kind of telesurgery, shows the 3D volume rendering image to be very good, actually a visualization standard that allows imaging likewise the real intraoperative anatomy. Computer communications and collaboration in our Tele-3D-C-FESS based on CT images and 3D models between two locations worked well, but the video image quality was inadequate for telesurgery procedures because images of 320x240 pixels with only 5 frames per second were transferred. The basic video image as a standard record of the operation was only used as a standard record of the course of operation. The use of minimally invasive surgical methods such as FESS and Tele-FESS has imposed the need of as reliable as possible preoperative imaging of the spatial anatomic relationship in the respective region. In the region of paranasal sinuses, such an image is of paramount importance for the surgeon or tele-expert-surgeon because of the proximity of intracranial structures and limited operative field layout hampering spatial orientation during the operative procedure. During our pilot projects, 3D-C-FESS and Tele-3D.-C-FESS, we used several standards to encode live video signals in telesurgery, such as M-JPEG, MPEG1 and MPEG2. It has been definitely concluded that MPEG2 streams, without audio, have the best picture quality for the operating field/endo camera. For conferencing/consultation cameras used between two or more connected sites during the surgery, we used JPEG and MPEG1 stream with audio. Operating rooms were connected using several computer network technologies with different bandwidths, from T1, E1 and multiple E1 to ATM-OC3 (from 1Mb/s to 155Mb/s). For computer communications using X-protocol for image/3D-models manipulations, we needed an additional 4Mb/s of bandwidth, instead of the 1Mb/s when we used our own communication tools for the transfer of surgical instrument movements. The bandwidth for the transfer in one direction of one MPEG2 stream without audio and one MPEG1 with audio was about 10MB/s.

Izvorni jezik
Engleski

Znanstvena područja
Kliničke medicinske znanosti

POVEZANOST RADA