The mechanisms of blood vessel closure in humans by the application of ultrasonic energy.
BACKGROUND
The use of the ultrasonically activated scalpel (UAS) for vessel closure has attained widespread acceptance in many surgical fields. The aim of our study was to investigate the electron microscopic changes to the blood vessels after the application of UAS.


METHODS
We collected 10 arterial and 10 venous segments from vessels that had previously been closed by UAS during abdominal operations. The samples were then prepared for ultramicroscopic analysis. Pathological changes in the lumen and the three wall layers of the blood vessel were examined under scanning and transmission electron microscopy.


RESULTS
All of the vessel segments showed similar changes: the presence of a blood clot, endothelial cell condensation, coagulative necrosis of the wall, and charring of the vessel at its tip. The edge of the cut vessel were closed by the coagulation bond, which was tied up by collagen fibrils escaped from denaturation.


CONCLUSIONS
When ultrasonic energy is applied to tissues, it changes their structure so as to make a new extracellular matrix.
Foschi
D
D
First Department of Surgery, Institute of Biomedical Sciences Luigi Sacco, Luigi Sacco Hospital, University of Milan, via G.B. Grassi 74, 20157 Milan, Italy. diego.foschi@unimi.it
Cellerino
P
P
Corsi
F
F
Taidelli
T
T
Morandi
E
E
Rizzi
A
A
Trabucchi
E
E
D003549:Cystic Duct / Q000098:blood supply / Q000000981:diagnostic imaging / Q000601:surgery / Q000648:ultrastructure; D004564:Electrocoagulation / Q000379:methods*; D006484:Hemorrhoids / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D006801:Humans; D008854:Microscopy, Electron / Q000379:methods; D008855:Microscopy, Electron, Scanning / Q000379:methods; D009336:Necrosis; D009852:Omentum / Q000098:blood supply / Q000000981:diagnostic imaging / Q000648:ultrastructure; D013270:Stomach / Q000098:blood supply / Q000000981:diagnostic imaging / Q000648:ultrastructure; D014464:Ultrasonic Therapy / Q000379:methods*; D014463:Ultrasonography; D014656:Vascular Surgical Procedures / Q000379:methods*