Patent CA-2709670-A1 (CA)
Inventor: ROSS DAVID B
IPC: A61B5/00
Filed: 2010-08-12
Abstract: This document describes a method for evaluating abnormal sensations in humans. Many conditions and injuries cause abnormal sensations in humans.  These include conditions affecting the nervous system directly and indirectly. In general, these abnormal sensations can be grouped into two categories - negative and positive phenomena. Negative phenomena include anesthesia, analgesia, proprioceptive loss and others. Positive phenomena include dysethesias, hyperpathia and others.  These subjective complaints are usually reported by the subject to a healthcare provider who diagnoses their root causes and severity. These sensory complaints are complex and are comprised of multiple different influences; including (a) the tissue injury itself usually peripheral nerve or nerve root; (b) central nervous system adaptations; (c) emotional components; [d] perceptual determinants and [e] depictive constituents.  The current method precisely combines several components: (a) new concept of external stimulation called the Aganaktic Recognition Level [ARL]; (b) the simultaneous measurement of an external sensory stimulatus with recording of verbal and non-verbal patient responses; (c) these non-verbal responses involve somatic and autonomic outputs that are ubiquitously evoked by an aganaktic stimulation; (d) recording these autonomic responses before, during, and after the ARL application to assess emotional components of the patient's experience; [e] comparing responses sequentially at matched control and test sites such that the person serves as his/her own control; and (f) routinely using multiple test sites and stimulation techniques to comprehensively evaluate the full extent of the subject's full sensory experience [including positive and negative phenomena]. One half of a sample trial run can be described as follows: (a) Electrodes are attached the subject to monitor autonomic responses (including skin conductance, heart rate, blood volume pulse, and others); (b) four surface EMG electrodes are applied to selected surface muscles; (c) once the electrodes are placed the patient is allowed to rest and enter a baseline state of relative relaxation; (d) at the specifically selected control site, a desired stimulation modality is gradually applied; (e) when the stimulus intensity reaches the Aganaktic Recognition Level, the patient depresses a button denoting that a level of sensory irritation has been reached; (f) this level of stimulus is maintained for several seconds and released; (g) the patient is allowed to rest;  autonomic and electromuscular responses are recorded before, during, and after ARL  application; (h) this process is repeated to insure reproducibility; (i) once the control site has been studied, the same process is (steps a though h) are reproduced exactly at the matched test site. This exact replication allows an intra-subject evaluation of physical tenderness and reactive responses between a neutral region and site of interest. This sample trial is repeated using different paired sites and modalities in a sequential fashion until all sites and issues are addressed specific to that patient.  Usually, this requires two to four sets of trials for a given subject. This specific combination of (a) simultaneous recording of verbal, autonomic and muscular reactions; (b) stimulation to an innovative, verbalized level of sensory experience; (c) systematic comparison of responses between precisely paired control and test sites; and (d) multiple trials of different sites and stimulus modes;  allows new conclusions and information concerning the physico-sensory, psychobiological, and sociodynamic bases for the test subject's pain experience.