FIRST EXPERIENCES WITH LAPAROSCOPIC INTRA OPERATIVE ULTRASOUND

Preoperative ultrasound as well as intraoperative laparoscopic diagnos is have both their limits, a fact that might be significant for laparo scopic surgical management. In particular, since in this surgical doma in, where almost everything has become technically feasible, the opera tor must decide what is to the benefit of the patient. A possible solu tion could be laparoscopic ultrasound, i.e. ultrasound diagnosis per l aparoscopy at the very site of the lesion. The advantages are evident. Due to the closeness to the organ to be examined, the frequency of th e scan head can be extremely high, resulting in better resolution. Als o, structures could be visualized by ultrasound which e.g., due to adh esions cannot be seen with the laparoscope. Moreover, ultrasound offer s a view into the structures which can be seen only from the exterior with the laparoscope, To perform these examinations we used a speciall y designed scanhead (Toshiba): Instead of the optical system a crystal array was inserted into a conventional gastroscope. The result was a high resolution 7.5 MHz linear array at the distal end of a freely mov able gastroscope. Colour doppler sonography is feasible with this scan head, We examined 19 patients, 16 of them with ovarian tumours, and at tempted visualization of the uterine myometrium/endometrium as well as of the liver. In six cases of ovarian tumours in which only cystic st ructures were found by preoperative transvaginal sonography, laparosco pic ultrasound additionally revealed solid inner structures. In 5 case s direct laparoscopic view of the ovarian lesions was impossible due t o severe adhesions. They were, however easily detected by intraoperati ve ultrasound, Colour representation of the blood flow was very well s uited to avoid considerable blood loss during surgery, since blood sup ply of the structures could be monitored during the entire procedure. The same is valid in cases of uterine surgery. Examinations of the liv er revealed in 1 case a metastasis which had not been detected by tran sabdominal sonography. Intraoperative ultrasound thus presents clear a dvantages for laparoscopic surgery: a direct view into and behind stru ctures becomes feasible, and by visualizing blood sup,ly of the operat ion site it may act as a ''guide'' to the laparoscopic surgeon, adding to the security of the procedure. More detailed information can be ob tained by laparoscopic ultrasound than by conventional sonographic exa mination; even structures can be detected that were inaccessible to co nventional ultrasound procedures. Improvements in diagnosis and stagin g of tumours will be the benefit of this new technique.