Risk evaluation of thermal injury to the cervical spine during intradiscal laser application in vitro.
OBJECTIVE
We aimed to investigate temperature distribution during laser and its possible thermal damage to the neurovascular structures.


BACKGROUND
Percutaneous laser disc decompression (PLDD) is now being performed as a minimally invasive intradiscal technique for the operative therapy of non-sequestered herniated cervical discs. As yet, no experimental basic research has been reported with regard to temperature rise and distribution in the cervical region during laser radiation.


METHODS
An in vitro laser procedure was performed on human cervical intervertebral discs under standardized conditions. A thermo-camera was used to monitor in real-time the zones sensitive to temperature increase.


RESULTS
Average intervertebral disc volume was 2000 mm3. With a total energy conduction of 600 Joules, a temperature increase of around 30 degrees C was shown with an initial temperature of 28 degrees C at the posterior longitudinal ligament lying immediately in front of the myelon. The defect volume was less than 1% of the total intervertebral disc volume.


CONCLUSIONS
If, during laser application, the total amount of conducted energy is too high, with an unfavorable position of the fibers in the intervertebral space, there is a risk of thermal damage to the spinal cord and nerve roots.
Schmolke
Stephan
S
Orthopedics Department, Hannover Medical School, Hannover, Germany. schmolke@annastift.de
Kirsch
Ludger
L
Gossé
Frank
F
Flamme
Christian
C
Bohnsack
Michael
M
Rühmann
Oliver
O
D002574:Cervical Vertebrae / Q000293:injuries*; D006801:Humans; D007834:Lasers; D013696:Temperature; D013817:Thermography