Journal of Ultrasound in Medicine, Vol 17, Issue 9 571-576, Copyright © 1998 by American Institute of Ultrasound in Medicine
Intraoperative ultrasonographically guided cryoablation of renal masses: initial experience
H. G. Zegel, G. A. Holland, S. B. Jennings, W. K. Chong and J. K. Cohen
Department of Radiologic Imaging, Allegheny University Hospitals-Medical College of Pennsylvania, Philadelphia 19129, USA.
The purpose of this study was to evaluate the feasibility of intraoperative
ultrasonography to guide cryoablation of renal masses. Renal cryoablation
was performed on six patients with solid renal tumors. Under
ultrasonographic guidance, cryoprobes measuring 3 mm in diameter were
placed into the renal tumor parenchyma or into surrounding normal
parenchyma. Intraoperative ultrasonography accurately delineated tumor
size, cryoprobe placement, and depth of freezing. An echogenic interface
was generated by the marked impedance differences at the junction of the
normal renal parenchyma and frozen tissue. In addition, intraoperative
ultrasonography identified a total of nine additional lesions in three
patients that were not detected by preoperative imaging. These lesions also
were treated cryosurgically during the same operation. There were no
deaths. The patients have been followed with clinical and laboratory
assessments as well as with MR imaging or CT scanning, and all have
remained tumor free 3 to 22 months postoperatively. Ultrasonographically
guided renal cryoablation is a feasible technique for treating malignant
renal tumors while preserving renal parenchyma. Long-term follow-up studies
in a larger series of patients are required to determine the true efficacy
and safety of this procedure.
