The antivascular action of physiotherapy ultrasound on murine tumors.
This study was aimed at determining if physiotherapy ultrasound (US) affected the fragile and leaky angiogenic blood vessels in a tumor. In 22 C3HV/HeN mice, a subcutaneous melanoma (K1735(22)) was insonated (1, 2 or 3 min) with continuous 1-MHz low-intensity (spatial-average temporal-average = 2.28 W cm(-2)), physiotherapy US. Contrast-enhanced (0.1 mL Optison) power Doppler US observations were made and histogram analyses of the images were performed. Before insonation, all but 7% of the tumor was perfused. The avascular area in tumors receiving 3-min treatment increased to 82% (p < 0.001). A linear regression analysis showed that each min of insonation led to a 25% reduction in tumor vascularity; the antivascular activity persisted for 24 h. Histology demonstrated disruption of vascular walls and tumor cell death in areas of vascular congestion and thrombosis. Physiotherapy US particularly targeted the vascular structures, and the effects on tumor cells appeared to be secondary to the resultant ischemia.
Wood
Andrew K W
AK
Department Clinical Studies (Phila), School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA.
Ansaloni
Sara
S
Ziemer
Lisa S
LS
Lee
William M-F
WM
Feldman
Michael D
MD
Sehgal
Chandra M
CM
D000418:Albumins; D000818:Animals; D003287:Contrast Media; D005260:Female; D005466:Fluorocarbons; D006358:Hot Temperature; D007091:Image Processing, Computer-Assisted; D008546:Melanoma, Experimental / Q000098:blood supply* / Q000000981:diagnostic imaging / Q000628:therapy; D051379:Mice; D008809:Mice, Inbred C3H; D009389:Neovascularization, Pathologic / Q000000981:diagnostic imaging / Q000628:therapy*; D012878:Skin Neoplasms / Q000098:blood supply* / Q000000981:diagnostic imaging / Q000628:therapy; D013997:Time Factors; D014464:Ultrasonic Therapy / Q000009:adverse effects / Q000379:methods*; D018615:Ultrasonography, Doppler, Color
D000418:Albumins; D003287:Contrast Media; C099458:FS 069; D005466:Fluorocarbons