title: The value of fused SPECT/CT in the evaluation of solitary skull lesion.
abstract: OBJECTIVE
  The aim of this study was to evaluate the role of single photon emission computed tomography and/or computed tomography (SPECT/CT) in differentiating metastatic from benign solitary skull lesions.
  
  
  METHODS
  Consecutive patients who had a SPECT/CT of the head subsequent to a whole-body bone scan (WBS) for the evaluation of a single skull lesion were selected. A single skull lesion on the WBS was further evaluated with SPECT/CT to characterize the lesion. The results of the SPECT/CT were correlated with other radiologic examinations performed within 2 weeks. An average follow-up interval after the SPECT/CT was 8.9 months to correlate with additional radiologic imaging studies and clinical information.
  
  
  RESULTS
  A total of 19 lesions in 19 patients were seen on the WBS and 2 additional lesions on the SPECT/CT. All lesions demonstrated focal increased tracer uptake. The SPECT/CT correctly identified 3 out of 3 metastatic lesions and 12 out of 17 benign lesions, that is 71% of lesions were correctly classifised as metastatic or benign lesions. Only 1 patient was classified incorrectly as metastatic lesion with SPECT/CT when it was proven benign by other imaging modalities and follow-up. The sensitivity, specificity, positive and negative predictive values of SPECT/CT images in identifying metastatic lesions were 100%, 92%, 75%, and 100%, respectively. Five lesions remained indeterminate even after the SPECT/CT interpretation and were confirmed benign by other imaging modalities.
  
  
  CONCLUSIONS
  SPECT/CT can help identify benign versus metastatic solitary skull lesions in most of the patients with high sensitivity and specificity.
authors.affiliation: University of Texas Health Sciences Center at Houston, Houston, TX, USA. isis.w.gayed@uth.tmc.edu
authors.forename: Isis W
authors.initials: IW
authors.lastname: Gayed
authors.forename: E Edmund
authors.initials: EE
authors.lastname: Kim
authors.forename: John
authors.initials: J
authors.lastname: Awad
authors.forename: Usha
authors.initials: U
authors.lastname: Joseph
authors.forename: David
authors.initials: D
authors.lastname: Wan
authors.forename: Susan
authors.initials: S
authors.lastname: John
mesh_terms: D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012886:Skull / Q000000981:diagnostic imaging* / Q000473:pathology; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed; D051598:Whole Body Imaging