title: Hybrid SPECT-CT for characterizing isolated vertebral lesions observed by bone scintigraphy: comparison with planar scintigraphy, SPECT, and CT.
abstract: OBJECTIVE
  We aimed to assess the role of single photon emission computed tomography-computed tomography (SPECT-CT) for characterizing isolated vertebral lesions observed by bone scintigraphy compared to planar scintigraphy, SPECT, and CT, and to evaluate the impact of SPECT-CT on patient management.
  
  
  METHODS
  Data from 99 patients (mean age, 52.4±18.9 years; females, 58.5%) with 108 isolated vertebral lesions visible on planar bone scintigraphy, who had undergone SPECT-CT of a selected volume, were retrospectively analyzed. Planar scintigraphy, SPECT, CT, and SPECT-CT images were independently evaluated in separate sessions to minimize recall bias. A scoring scale of 1 to 5 was used, with 1 being definitely metastatic, 2 most likely metastatic, 3 indeterminate, 4 most likely benign, and 5 definitely benign. Sensitivity, specificity, and predictive values were calculated; a score ≤3 was defined as metastatic. The areas under the receiver operating characteristic curve were calculated and compared. Clinical and imaging followup with or without histopathology were used as a reference standard.
  
  
  RESULTS
  Among the 108 lesions, 49 were indeterminate on planar scintigraphy, 16 on SPECT, and one each on SPECT-CT and CT. SPECT-CT was superior to both planar scintigraphy (P < 0.001) and SPECT alone (P = 0.014), but not to CT (P = 0.302). CT was superior to planar scintigraphy (P < 0.001) but only slightly superior to SPECT (P = 0.063). SPECT-CT correctly characterized 96% of the indeterminate lesions observed by planar scintigraphy. SPECT-CT had an impact on the clinical management of 60.6% patients compared to planar scintigraphy and 18.1% compared to SPECT.
  
  
  CONCLUSIONS
  SPECT-CT is better than planar scintigraphy and SPECT alone, but not CT alone, for characterizing equivocal vertebral lesions that are observed by bone scintigraphy, thus SPECT-CT can have a significant impact on patient management.
authors.affiliation: Department of Nuclear Medicine, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Punit
authors.initials: P
authors.lastname: Sharma
authors.forename: Varun Singh
authors.initials: VS
authors.lastname: Dhull
authors.forename: Rama Mohan
authors.initials: RM
authors.lastname: Reddy
authors.forename: Chandrasekhar
authors.initials: C
authors.lastname: Bal
authors.forename: Sanjay
authors.initials: S
authors.lastname: Thulkar
authors.forename: Arun
authors.initials: A
authors.lastname: Malhotra
authors.forename: Rakesh
authors.initials: R
authors.lastname: Kumar
mesh_terms: D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D012372:ROC Curve; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013125:Spinal Neoplasms / Q000000981:diagnostic imaging*; D013131:Spine / Q000000981:diagnostic imaging; D013669:Technetium Tc 99m Medronate; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D019275:Radiopharmaceuticals; D013669:Technetium Tc 99m Medronate