Reliability of Gadolinium-enhanced MRI findings and their correlation with clinical outcome in patients with sciatica

Abstract

BACKGROUND CONTEXT:

Gadolinium-enhanced Magnetic resonance imaging (Gd-MRI) is often performed in the evaluation of patients with persistent sciatica after lumbar discsurgery. However, correlation between enhancement findings and clinical findings is debated and limited data is available regarding the reliability of enhancement findings.

PURPOSE:

To evaluate the reliability of Gd-MRI findings and their correlation with clinical findings in patients with sciatica.

STUDY DESIGN/SETTING:

Prospective observational evaluation of patients who were enrolled in a randomized trial with one year follow-up.

PATIENTS SAMPLE:

Patients with 6-12 weeks sciatica who participated in a multicentre randomized clinical trial comparing an early surgery strategy to prolonged conservative care with surgery if needed. In total 204 patients underwent Gd-MRI at baseline and after one year.

OUTCOME MEASURES:

Patients were assessed by means of the Roland Disability Questionnaire (RDQ) for Sciatica, visual-analogue scale (VAS) for leg pain and patient-reported perceived recovery at one year. Kappa coefficients were used to assess interobserver reliability.

METHODS:

In total 204 patients underwent Gd-MRI at baseline and after one year. MRI findings were correlated to the outcome measures using The Mann-Whitney U test for continuous data and Fisher's exact tests for categorical data. This study was supported by a grant from the Netherlands Organisation for Health Research and Development (ZonMW) and the Hoelen Foundation, The Hague. None of the authors of this study has any conflict of interest.

RESULTS:

Poor to moderate agreement was observed regarding gadolinium enhancement of the herniated disc and compressed nerve root (kappa <0.41) which was in contrast with excellent interobserver agreement about the disc level of the herniated disc and compressed nerve root (kappa >0.95). Of the 59 patients with an enhancing herniated disc at one year, 86% reported recovery compared to 100% of the 12 patients with non-enhancing herniated discs (P=0.34). Of the 12 patients with enhancement of the most affected nerve root at one year 83% reported recovery compared to 85% of the 192 patients with no enhancement (P=0.69). Patients with and without enhancing herniated discs or nerve roots at one year reported comparable outcomes on RDQ and VAS-leg pain.

CONCLUSION:

Reliability of Gd-enhanced MRI findings was poor to moderate and no correlation was observed between enhancement findings and clinical findings at one year follow-up.

Copyright © 2014 Elsevier Inc. All rights reserved.

KEYWORDS:

Sciatica, clinical outcome, conservative treatment, disc herniation, follow-up, gadolinium-enhanced MRI findings, surgery

PMID:

 

24561397

 

[PubMed - as supplied by publisher]