A feasibility study of two dimensional (2D) nerve root retractor is presented. Reasons for 2D measurements of retraction force during lumbar discectomy are discussed. Design details of 2D retractor, based on simulation results from finite element analysis software ANSYS are shown. Evolutionary phase of 2D retractor design and fabrication is described and characterization results on finished device are reported. As a result of this characterization, basic properties of 2D medical retractor, such as sensitivity and output voltage response are presented and analyzed.
COBISS.SI-ID: 7254868
H-reflex and spinal nerve root potentials were realized for the first time for evaluation of mechanical load to spinal nerve root during necessary and mostly unavoidable surgical manipulation of the root in removal of herniated lumbar disc. Decrement or loss of the signal informed a surgeon of a dangerous mechanical load to the root in on-line manner and prevented permanent injury of the root. Piezoresistive retractor will enable determination of the critical mechanical load to the root.
COBISS.SI-ID: 516191257
Design, fabrication, characteristics and lab test results of the prototype of nerve root retractor are presented at the international conference
COBISS.SI-ID: 6642772
Measurement setup and data acquisition method for simultaneous recording of retractor output response and video signal is introduced and tested in real environment. Based on obtained results, random errors such as noise, hum, distortions and crosstalk in retractor response were analyzed and discussed. Using retractor prototype with calculated sensitivity of 15,8 µV/V/g, resolution of the proposed measurement setup in the value of 1,7g was determined.
COBISS.SI-ID: 7934292
The reflex muscle evoked potential from the soleus muscle (H-wave), P1-wave (ascendant) and P2-wave (descendant volley) paralleled the surgical manipulation. The amplitude of the H-wave significantly decreased (p<0.001) and the degree of positivity of P1-wave (computed offline in 8 of 12 patients) significantly increased (p<0.0473) after mobilization of the root with a dissector and in the late phase of intervertebral disc evacuation, indicating conduction dysfunction related to surgical manipulation of the root.
COBISS.SI-ID: 26194137