Biomedical subjects

S Shimon

Publications and source records attributed to S Shimon.

2 recordsLinked to original sources

PubMed1991

Effects of compression and devascularisation on ulnar nerve function. A quantitative study of regional blood flow and nerve conduction in monkeys.

This study investigated the effects of compression, devascularisation and ischaemia with compression on blood flow and function of the ulnar nerve in monkeys. The hydrogen washout technique assessed blood flow; nerve conduction tests determined nerve function. 100 g of external compression produced a significant but incomplete reduction of intraneural blood flow, when conduction velocity decreased significantly and response amplitude deteriorated to zero 28 minutes after the onset of compression. Short-segment devascularisation stopped blood flow but did not influence response latency or velocity. Amplitude was diminished significantly 44 minutes after devascularisation. Tourniquet ischaemia followed by compression produced temporary variability in latency and velocity, while amplitude was diminished only during the compression phase following ischaemia. The overall results suggested that compression and ischaemia influence the nerve conduction response differently and that the effects of compression are potentiated by previous ischaemia, even if this was of short duration.

Animals↗

PubMed1988

Sensitivity and specificity of somatosensory and neurogenic-motor evoked potentials in animals and humans.

The purpose of this study was to report the effects of spinal cord compression, ischemia, and distraction on clinical status, and somatosensory (SEP) and neurogenic-motor evoked potentials (NMEPs) in animals. The authors also reported their clinical experience with NMEPs elicited from humans undergoing surgery for spinal deformities. Results from the animal studies indicate that NMEPs are more sensitive and specific to the effects from spinal cord compression, ischemia, and distraction than SEPs. In every situation, NMEPs always correlated with the animal's post-surgical clinical status, while SEPs demonstrated an unacceptable false positive and false negative rate. In the 111 clinical cases in which NMEPs were administered, reliable NMEPs were easily elicited in more than 90% of the cases. In the remaining cases, no reliable NMEPs could be recorded because of procedural errors, which have been resolved. The results from this study suggest that the use of NMEPs should be considered as an adjunct to SEPs when monitoring spinal cord function during surgery.

Animals↗