Correlation between changes in regional cerebral blood flow and pain relief in complex regional pain syndrome type 1.
OBJECTIVE
Analyzing changes in regional cerebral blood flow (rCBF) with SPECT in complex regional pain syndrome type 1 (CRPS 1), formerly known as reflex sympathetic dystrophy, is an optimal method for evaluating effective pain relief. We attempted to investigate the correlation of changes in rCBF with pain relief during treatments of sympathetic blockade and multimodal epidural pain control.


METHODS
We describe a patient with severe CRPS 1 in whom conventional treatment failed to relieve the pain. Combined repeated lumbar sympathetic blocks and long-term epidural morphine, bupivacaine, and ketamine administration provided satisfactory pain relief and functional activity recovery. Six normal control subjects having one Tc-99m HMPAO scan each and the patient with CRPS having 3 Tc-99m HMPAO scans (once before treatment and twice at 4 months and 6 months after treatment, respectively). The patient with CRPS showed lower rCBF than normal controls in the left thalamus and higher rCBF than normal controls in the right parietal lobe and left frontal lobe. After subsequent treatment, the subtraction images showed increased rCBF in the left thalamus and decreased rCBF in the right parietal and left frontal lobes.


CONCLUSIONS
Tc-99m HMPAO SPECT showed a relationship of rCBF in the thalamus, parietal lobe, and frontal lobe with pain relief. rCBF alterations may provide an indicator for the quality of pain management for neuropathic pains. Subtraction analysis between pre- and posttreatment, by using statistical parametric mapping (version 2), can be used as an objective indicator for the effectiveness of therapy.
Wu
Ching-Tang
CT
Department of Anesthesiology, Tri-Service General Hospital, National Defense Medical Center, Taiwan.
Fan
Yu-Ming
YM
Sun
Chen-Ming
CM
Borel
Cecil O
CO
Yeh
Chun-Chang
CC
Yang
Chih-Ping
CP
Wong
Chih-Shung
CS
D000328:Adult; D001921:Brain / Q000098:blood supply* / Q000000981:diagnostic imaging*; D002560:Cerebrovascular Circulation; D006801:Humans; D008297:Male; D010147:Pain Measurement / Q000379:methods*; D011379:Prognosis; D019275:Radiopharmaceuticals; D012019:Reflex Sympathetic Dystrophy / Q000000981:diagnostic imaging* / Q000628:therapy*; D013223:Statistics as Topic; D019690:Technetium Tc 99m Exametazime; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods; D016896:Treatment Outcome
D019275:Radiopharmaceuticals; D019690:Technetium Tc 99m Exametazime