Intracarpal tunnel contents: evaluation of the effects of corticosteroid injection with sonoelastography.
OBJECTIVE
To define the stiffness of the intracarpal tunnel contents and to evaluate the effect of corticosteroid injection on the intracarpal tunnel contents by using sonoelastography.


METHODS
This study was conducted with the approval of the institutional review boards, and all participants provided written, informed consent. Both hands were studied in 20 healthy volunteers, including eight men (mean age, 59.6 years; range, 50-76 years) and 12 women (mean age, 61.0 years; range, 39-79 years) and 22 hands were studied in 20 patients with carpal tunnel syndrome (CTS) (five men [mean age, 49.0 years] and 15 women [mean age, 61.1 years]; range, 39-89 years) between April 2012 and August 2012. The stiffness of the intracarpal tunnel contents was estimated as the standardized acoustic coupler (AC)-to-intracarpal tunnel contents surrounding the nerve (AC/C) strain ratio, analyzed with the Mann-Whitney U test. The patients were treated with corticosteroid injections, and the strain ratio was reexamined 6 weeks later, analyzed with the Wilcoxon t test.


RESULTS
The mean AC/C strain ratio in the CTS patients was 12.6 ± 4.7 (standard deviation), which was higher (stiffer) than that in the healthy volunteers with a mean strain ratio of 8.2 ± 3.5 (P = .0013). Six weeks after the injection, the mean AC/C strain ratio had decreased to 8.5 ± 4.1 (P = .00069, compared with the preinjection value) in the CTS patients.


CONCLUSIONS
The stiffness of the intracarpal tunnel contents in untreated CTS patients is higher than that of healthy volunteers but decreases 6 weeks after corticosteroid injection.
From the Department of Diagnostic Radiology (H.M., C.S., M.K., W.R.J., A.S.K.) and Department of Trauma Surgery and Sports Medicine (M.G.), Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck, Austria; and Cattedra "R" di Radiologia-DICMI, Università di Genova, Genoa, Italy (C.M.).
Hideaki
H
Miyamoto
Christian
C
Siedentopf
Martin
M
Kastlunger
Carlo
C
Martinoli
Markus
M
Gabl
Werner R
WR
Jaschke
Andrea S
AS
Klauser
D000305:Adrenal Cortex Hormones / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002349:Carpal Tunnel Syndrome / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D054459:Elasticity Imaging Techniques; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D007267:Injections; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome
D000305:Adrenal Cortex Hormones