Interobserver variation of single-photon emission computed tomography bone scans in patients evaluated for unilateral condylar hyperactivity

Oral Surg Oral Med Oral Pathol Oral Radiol. 2013 Mar;115(3):399-405. doi: 10.1016/j.oooo.2012.11.016.

Abstract

Objective: This study assessed the quantitative evaluation of the region of interest (ROI) by mean and maximum pixel counts of single-photon emission computed tomography (SPECT) scans in patients with clinical suspicion of unilateral condylar hyperactivity (UCH); the interobserver reliability and the correlation of condylar activity with patient age was determined.

Methods: Two independent observers analyzed 67 bone SPECT scans. Maximum and mean activity values within an ROI on the mandibular condyle were analyzed; a cutoff value of 55% was used to determine the qualitative outcome.

Results: Excellent interobserver agreement was seen for both maximum (kappa 1.0) and mean activity analysis (kappa 0.94). Maximum and mean condylar activities were strongly correlated (r > 0.98). Maximum and mean condylar activity of the normal condyle decreased significantly with increasing age.

Conclusions: Maximum and mean condylar activity levels were highly correlated in patients with mandibular asymmetry. An excellent interobserver agreement was found with either maximum or mean condylar activity.

MeSH terms

  • Adolescent
  • Adult
  • Age Factors
  • Child
  • Facial Asymmetry / diagnostic imaging
  • Female
  • Humans
  • Hyperplasia
  • Image Processing, Computer-Assisted / statistics & numerical data
  • Male
  • Mandibular Condyle / diagnostic imaging*
  • Observer Variation
  • Radiopharmaceuticals
  • Reproducibility of Results
  • Technetium Tc 99m Medronate / analogs & derivatives
  • Tomography, Emission-Computed, Single-Photon / methods
  • Tomography, Emission-Computed, Single-Photon / statistics & numerical data*
  • Young Adult

Substances

  • Radiopharmaceuticals
  • technetium Tc 99m hydroxymethylene diphosphonate
  • Technetium Tc 99m Medronate