New Cavitron system (CUSA/CEM): its application for kidney surgery

Partial nephrectomy driven by cavitron ultrasonic surgical aspirator under zero ischemia: a pilot study

PURPOSE

To investigate the efficacy and technical applicability of cavitron ultrasonic surgical aspirator (CUSA)-driven zero-ischemia open partial nephrectomy in patients with renal tumors.

MATERIALS AND METHODS

We prospectively collected data of 13 consecutive patients, who underwent open partial nephrectomy under non-ischemic conditions. Tumor resection was done using an ultrasonic device (CUSA/SONOCA 300). Demographic and laboratory data, tumor characteristics, perioperative, and postoperative variables were evaluated.

RESULTS

The median age was 60.0 years (range 40-76); body mass index 28.0 kg/m(2) (range 22.9-43.3); tumor size 37.0 mm (range 11-110 mm). Patient were stratified according to the PADUA score into low- (score 6-7; n - 4), intermediate- (score 8-9; n - 5), and high-risk (score of >10; n - 4) groups, and the median score was 9.0 (range 6-13; SD +2.3). The vast majority of kidney tumors were diagnosed incidentally (n - 11; 84.6 %). Median operative time was 175 min (55-270 min); median time of tumor extirpation was 12 min (6-25 min); and median blood loss was 250 ml. Serum creatinine, glomerular filtration rate, and hemoglobin were nearly unaltered before and after surgery in 11 cases (84.6 %). Three patients received a blood transfusion (Clavien-Dindo Grade II); one had Grade IIIa complication (insertion of double J stent without general anesthesia); and three had Grade IIIb complications (insertion of double J under general anesthesia).

CONCLUSIONS

The ultrasonic device demonstrated acceptable hemostatic and resection properties during open partial nephrectomy without ischemia. Our series showed promising perioperative and postoperative outcomes that may help in maximizing preservation of renal function in partial nephrectomy candidates.

Low-power transverse ultrasonic treatment of portal vein thrombosis in an animal model

PURPOSE

The authors have recently developed a small-diameter, thin, flexible ultrasonic catheter device that permits the removal of thrombus by low-power transverse ultrasonic cavitation energy. In this study, the authors sought to determine whether this device could be used to eliminate portal vein thrombosis in an animal model.

MATERIALS AND METHODS

In five anesthetized pigs, a total of six occlusions of the left portal vein were achieved with use of autologous clot with (n = 2) or without (n = 4) thrombin injection (250 U) introduced via a 7-F transhepatic catheter/sheath system. Angiographic examination documented complete occlusion of this vessel. The 75-cm-long, 21-gauge ultrasonic catheter (Resolution) was introduced into the clot under angiographic guidance via the transhepatic sheath. Transverse-wave ultrasonic energy was then delivered from the distal 5 cm of the probe at 3.5 W +/- 10% power for up to 6 minutes. Repeat angiographic studies were performed to document patency. After the procedure, gross and histopathologic examinations were performed.

RESULTS

Restoration of patency of the main left portal vein was documented in all cases at angiography, with no evidence of residual clot fragments in the major branches. However, side branches demonstrated small thrombotic plugs on pathologic examination. No complications such as perforation of the vessel adjacent to the active ultrasonic tip were encountered. Virtually all thrombolysis was documented to occur within the first minute of energy application. At gross pathologic examination, there was no evidence of damage to the portal vein, and histopathologic examination demonstrated minimal intimal disruption without damage to the media.

CONCLUSIONS

This preliminary animal study suggests the feasibility of a percutaneous transhepatic approach to the treatment of portal vein thrombosis with use of low-power ultrasonic cavitation energy. With further study, this method may have potential for the treatment of thrombotic disease, thereby offering novel therapy to patients with thrombotic vascular occlusions.

Water-jet dissection in renal surgery: experimental study of a new device in the pig

The pig model was used for experiments with a new type of water-jet dissector, which produces high-pressure water by application of a gas and maintains the water fully sterile in a single-use delivery apparatus. The experiment was conducted ex vivo (14 kidneys) and in vivo to compare electric cautery section with water-jet dissection (5 vs 11 partial nephrectomies). Ex vivo study confirmed sparing of blood vessels and pelvicaliceal system. In vivo study did not show significant differences in blood loss but, the water-jet allowed precise dissection and tight closure of the excretory system. More frequent haemorrhages were noted on histological examination of the WJ group, but no coagulation necrosis. These are preliminary findings and further studies of long-term results may confirm the benefits of the absence of parenchymal necrosis and the definite advantage of precise closure of the pelvicaliceal system, as morbidity of partial nephrectomy is often related to secondary haemorrhages and urinary fistulae.