Soft tissue dissection with an ultrasonic snare and the quantification of thermal spread

Soft tissue dissection with an ultrasonic snare and the quantification of thermal spread

Van de Berg, N.J.

Dankelman, J. (mentor)
Van den Dobbelsteen, J.J. (mentor)

Mechanical, Maritime and Materials Engineering

BioMechanical Engineering

BME

2011-12-16

Thermal spread is the extend of lateral damage resulting from soft tissue dissection by means of an energetic surgical instrument. Both a true definition of this factor, and a consistent means to quantify it, are still lacking. This study attempts to standardize thermal spread by 1) listing the relevant medical, technical, and statistical parameters, 2) selecting a soft tissue substitute to reduce biological influences, and 3) testing the protocol by determining the thermal spread of the Lotus grasper. Thermal spread was measured in a meat replacement product (quorn) by means of eight thermocouples. Spread of heat was determined as the distance between the instrument shaft and the 7:5_C isotherm. It was measured at 5 mm depth in the left (3:09 _ 0:637 mm), and right flank (2:70 _ 0:966 mm). In addition, two more depth levels were measured in the left flank, 2:5 mm (2:11_ 0:732 mm), and 7:5 mm (2:95_0:959 mm). The thermal distribution of the Lotus obtained by this measuring technique was comprehensible and educative. The use of thermocouples seemed adequate, as spread could be measured in the deep direction, and sufficiently precise. The selected test material (quorn) was sub- optimal from a mechanical viewpoint. This may have led to experimental uncertainties and an increased measurement variance.

ultrasonic
snare cutting
laparoscopy

http://resolver.tudelft.nl/uuid:26a8184d-5810-4825-917c-31b4e262a4c1

2013-01-01

Student theses

master thesis

(c) 2011 Van de Berg, N.J.