A Methodology Study Of Brain Imaging Of Pain-Killers In Post-Traumatic Neuropathic Pain Patients

BOLD brain activation signals in whole brain was assessed using Contrast Parameter Estimates (COPE) images in response to dynamic mechanical allodynia of the affected side (DMAa), dynamic mechanical allodynia of the control side (DMAc), thermal pain (TH) and checkerboard visual stimuli (VIS).

BOLD brain activation signals in pre-defined region of interest(ROI):anterior cingulate cortex(ACC);left,right anterior cortex([AIC_L ],[AIC_R]);left,right mid-insular cortex([MIC_L],[MIC_R]);left,right posterior insular cortex([PIC_L],[PIC_R]);left,right amygdala([Amyg_L],[Amyg_R]);primary,secondary somatosensory cortex([S1],[S2]);sensory part of thalamus(SensTHAL);midbrain reticular formation(MRF);nucleus cuneiformis(NucCun);periaqueductal gray(PAG). Prior to ROI analysis, a prelimanary anlysis was performed, wherein it was concluded that ROI analysis was to be carried out for DMAa, DMAc amd TH only. In voxel BOLD analysis,signal change is unit less measure but approximated to percent signal change by grand scaling(effects divided by 10000 to get percent signal change).

BOLD brain activation signals in pre-defined ROI. ROI were ACC; AIC_L; AIC_R; MIC_L; MIC_R; PIC_L; PIC_R; Amyg_L; Amyg_R; S1; S2; SensTHAL; MRF; NucCun; PAG. Prior to ROI analysis, a prelimanary anlysis was performed, wherein it was concluded that ROI analysis was to be carried out for DMAa, DMAc amd TH only. In voxel BOLD analysis, signal change is unit less measure but is approximated to percent signal change here by grand scaling (dividing effects by 10000 to get percent signal change).

BOLD brain activation signals in pre-defined ROI. ROI were ACC; AIC_L; AIC_R; MIC_L; MIC_R; PIC_L; PIC_R; Amyg_L; Amyg_R; S1; S2; SensTHAL; MRF; NucCun; PAG. Prior to ROI analysis, a prelimanary anlysis was performed, wherein it was concluded that ROI analysis was to be carried out for DMAa, DMAc amd TH only. In voxel BOLD analysis, signal change is unit less measure but is approximated to percent signal change here by grand scaling (dividing effects by 10000 to get percent signal change).

BOLD brain activation signals in pre-defined ROI in response to checkerboard visual stimuli (flashing at 2 Hz). ROI were ACC; AIC_L; AIC_R; MIC_L; MIC_R; PIC_L; PIC_R; Amyg_L; Amyg_R; S1; S2; SensTHAL; MRF; NucCun; PAG. Prior to ROI analysis, a prelimanary anlysis was performed, wherein it was concluded that ROI analysis was to be carried out for DMAa, DMAc amd TH only.

Continuous ASL sequence fMRI imaging modality assessing brain activation signals across the whole brain and in defined ROI to assess effects of evoked pain along with changes in regional cerebral blood flow (rCBF). ROI were ACC; AIC_L; AIC_R; MIC_L; MIC_R; PIC_L; PIC_R; Amyg_L; Amyg_R; S1; S2; SensTHAL; MRF; NucCun; PAG.

SF-36 is a standardized survey evaluating 8 aspects of functional health and well being: physical and social functioning, physical and emotional role limitations, bodily pain, general health, vitality, mental health. The score for a section is an average of the individual question scores, which are scaled 0-100 (100=highest level of functioning).

BDI is a 21 item participant rated inventory evaluating depression symptoms, cognition, and physical symptoms of fatigue, weight loss, lack of interest in sex. Individual items are scored on a 4 point scale (0 to 3), with 0=none/absent and 3=most severe. Total score: 0 to 63; higher score indicate more depression.

Self-report scale completed by the participant. Separate scales measure state (20 items) and trait (20 items) anxiety. The participant report how they feel "right now at this moment" for state anxiety and how they "generally" feel for trait anxiety. The "state" items are scored as: 1 (not at all), 2 (somewhat true), 3 (moderately true), 4 (very much so). The "trait" items are scored as: 1 (almost never), 2 (sometimes), 3 (often), 4 (almost always). Scores range from 20-80 for each scale. Higher scores indicate more impaired participants.

The PCS is a self-administered questionnaire with 13 items, each scored from 0 (not at all) to 4 (all the time) for extent to which participant catastrophizes postoperative pain. Total score is sum of scores for all questions (range: 0 to 52); Subscale scores: Rumination (sum of scores for 4 items; range: 0 to 16); Magnification (sum of scores for 3 items; range: 0 to 12); and Helplessness (sum of scores for 6 items; range: 0 to 24); higher scores indicate greater extent of pain catastrophizing.

NPSI: participant rated questionnaire to evaluate different symptoms of neuropathic pain (dimensions: burning [superficial] spontaneous pain, pressing [deep] spontaneous pain, paroxysmal pain, evoked pain, and paresthesia/dyesthesia [P/D]). Includes 10 descriptors quantified on a 0 (no symptoms) to 10 (worst symptoms imaginable) and 2 temporal items assessing duration of spontaneous ongoing and paroxysmal pain. Questionnaire generates a score in each of the relevant dimensions and a total score of 0-100. Higher score indicate a greater intensity of pain.

Daily Pain Score: Day 1 pain intensity over past 24 hours recorded on waking every morning using 0-10 numeric rating scale (NRS): 0 (no pain) to 10 (worst possible pain). The daily pain scores for an average of the last 7 days and an average of last 3 days were calculated.

Participants answered: "Please rate your pain from 0-10 that best describes the intensity of pain right now". PPIS assessed on 0-10 numeric rating scale (NRS), 0 (no pain) to 10 (worst possible pain).

DN4 questionnaire provides a simple diagnosis of Neuropathic pain (NeP) by asking for yes/no answers to 4 questions (10 sub questions in total). Each question was scored on a scale of 0 (No) and 1 (Yes). Total score was calculated as sum of the 10 individual questions. Total score range 0-10, higher score indicated more neuropathic pain.