We performed a retrospective review of the electronic medical record to identify patients who underwent sonographic evaluation of the median nerve and CTR surgery at Duke University within 4 months. Those with concurrent polyneuropathy were excluded. Surgical outcomes were determined by 2 independent reviewers based upon chart review of the postoperative visit 4-6 weeks after surgery. A 3rd reviewer assessed the outcome in the event of disagreement. Complete resolution was defined in the absence of paresthesia, pain, and functional limitation pertinent to carpal tunnel syndrome.
A total of 56 nerves from 50 patients were identified. Of these patients, 33 (66%) were women and the mean age was 57.2 years (SD = 14.2). Complete resolution occurred in 39 (69.6%) surgeries. Multivariable logistic regression model, adjusted for age and gender, showed no association between median nerve echointensity and complete versus partial resolution (OR=1.01; 95% CI = 0.99-1.03). Inter-rater reliability was excellent in both outcome assessment (% agreement = 96.4, kappa =0.92) and measurement of echointensity (interclass correlation: 0.914).
Our study did not demonstrate differences in preoperative median nerve echointensity between patients with complete and partial resolution of symptoms following CTR surgery. However, the measurement of echointensity and outcomes assessment had excellent interrater reliability. A multi-center prospective study should be pursued for better understandings of the relationship between NUS parameters and the outcomes of CTR surgery.