title: 99mTc-Methylene diphosphonate SPECT/CT as the one-stop imaging modality for the diagnosis of osteoid osteoma.
abstract: OBJECTIVE
  The aim of this study was to evaluate the utility of Tc-methylene diphosphonate (Tc-MDP) single-photon emission tomography (SPECT)/computed tomography (CT) for the diagnosis of osteoid osteoma and compare the same with three-phase planar bone scintigraphy (BS) and CT alone.
  
  
  METHODS
  Data of 31 patients (age: 20.6±13.2 years; male: 80.6%) who had undergone Tc-MDP BS with SPECT/CT for clinically and/or radiographically suspected osteoid osteoma were retrospectively evaluated. Planar BS images were analyzed by an experienced nuclear medicine physician. CT images were evaluated by an experienced radiologist. SPECT/CT images were evaluated by the nuclear medicine physician and radiologist in consensus. On the basis of the diagnostic confidence the interpreters used a scoring scale of 1-3, in which 1 is negative for osteoid osteoma, 2 is equivocal, and 3 is positive for osteoid osteoma. For the calculation of sensitivity, specificity, and predictive values for planar BS, CT, and SPECT/CT an interpretive score of 2 or higher was taken as positive for osteoid osteoma. Receiver operating characteristic curve analysis was performed and the area under the curve was calculated and compared. Histopathology and microbiology/clinical imaging follow-up was used as the reference standard.
  
  
  RESULTS
  There were nine equivocal lesions on planar BS and five equivocal lesions on CT, but none on SPECT/CT. The sensitivity, specificity, and accuracy of SPECT/CT were all 100%; those of CT were 77.8, 92.3, and 83.8% and those of planar BS were 100, 38.4, and 74.1%, respectively. On comparison, the area under the curve of SPECT/CT was significantly larger than that of planar BS (1.00 vs. 0.761; P=0.005) and CT (1.00 vs. 0.872; P=0.044). However, no significant difference was seen between planar BS and CT (0.761 vs. 0.872; P=0.236).
  
  
  CONCLUSIONS
  Tc-MDP SPECT/CT shows excellent diagnostic accuracy for osteoid osteoma and can be used as a one-stop imaging modality for the same. It is superior to planar BS and CT alone for the diagnosis of suspected osteoid osteoma.
authors.affiliation: Departments of aNuclear Medicine bRadiodiagnosis cOrthopaedics, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Punit
authors.initials: P
authors.lastname: Sharma
authors.forename: Anirban
authors.initials: A
authors.lastname: Mukherjee
authors.forename: Sellam
authors.initials: S
authors.lastname: Karunanithi
authors.forename: Jeyaseelan
authors.initials: J
authors.lastname: Nadarajah
authors.forename: Shivanand
authors.initials: S
authors.lastname: Gamanagatti
authors.forename: Shah A
authors.initials: SA
authors.lastname: Khan
authors.forename: Chandrasekhar
authors.initials: C
authors.lastname: Bal
authors.forename: Rakesh
authors.initials: R
authors.lastname: Kumar
mesh_terms: D000293:Adolescent; D000328:Adult; D001859:Bone Neoplasms / Q000000981:diagnostic imaging*; D002648:Child; D002675:Child, Preschool; D006801:Humans; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D010017:Osteoma, Osteoid / Q000000981:diagnostic imaging*; D012372:ROC Curve; D011877:Radionuclide Imaging; D012189:Retrospective Studies; D013669:Technetium Tc 99m Medronate; D014057:Tomography, X-Ray Computed; D055815:Young Adult
chemical_list: D013669:Technetium Tc 99m Medronate