Scalp and Thoracolumbar Area Recorded Somatosensory Potentials in Response to Tibial Nerve Stimulation in Cats
Ankara University Faculty of Veterinary Medicine Department of Surgery, Diskapi, Ankara Turkey
The purpose of the study was to define tibial somatosensory evoked potentials (SEPs) in 56 clinically normal adult cats.
The potentials recorded from the gastrocnemius muscle, sciatic nerve, L3-L4 and T12-T13 interarcuate ligament and the scalp were evaluated. Central conduction time was determined by the difference between scalp N1 and lumbar N1 latencies. Partly moving current source of the cord dorsum potentials that were small, brief and positive deflections, were recorded in different numbers for lumbar and thoracal area.
All three deflections representing moving current source were observed in lumbar area of 23 cats and thoracal area of 15 cats. The end point of the last positive potential (N3) was not clear. Amplitudes acquired from the muscle, sciatic nerve and scalp were conventional while the Ascendens Evoked Potential (AsEP) was similar to the cord dorsum potential. According to latency values, all of the recorded potentials showed homogenous dispersion except for lumbar P1 and thoracal P2 latency values. The latency values of lumbar and thoracal area was significantly different except for lumbar and thoracal inter-peak and P2 and P4 latency (P<0.05).
Somatosensory-evoked and spinal cord-evoked potentials can be used to assess the functional severity of the ascending tracts of the spinal cord accurately as well as sensory nerves, dorsal nerve roots and spinal cord dorsal horns in cats with suspected neuropathy.