title: Comparison of SPECT/CT and MRI in diagnosing symptomatic lesions in ankle and foot pain patients: diagnostic performance and relation to lesion type.
abstract: OBJECTIVE
  The purpose of this study was to compare the diagnostic performance of SPECT/CT and MRI in patients with ankle and foot pain, with regard to the lesion types.
  
  
  METHODS
  Fifty consecutive patients with ankle and foot pain, who underwent 99mTc-MDP SPECT/CT and MRI, were retrospectively enrolled in this study. Symptomatic lesions were determined based on clinical examination and response to treatment. On MRI and SPECT/CT, detected lesions were classified as bone, ligament/tendon, and joint lesions. Uptake on SPECT/CT was assessed using a 4-grade system. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of SPECT/CT and MRI were evaluated in all detected lesions and each lesion type. Diagnostic value of uptake grade was analyzed using receiver-operating characteristics (ROC) curve analysis, and diagnostic performance was compared using Chi-square or McNemar tests.
  
  
  RESULTS
  In overall lesions, the sensitivity, PPV and NPV of SPECT/CT for symptomatic lesions were 93%, 56%, 91%, and they were 98%, 48%, 95% for MRI. There was no significant difference between SPECT/CT and MRI. However, the specificity of SPECT/CT was significantly higher than that of MRI (48% versus 24%, P = 0.016). Uptake grade on SPECT/CT was significantly higher in symptomatic lesions (P < 0.001), and its area under curve on ROC analysis was 0.787. In the analysis of each lesion type, the specificity of SPECT/CT was poor in joint lesions compared with other lesion types and MRI (P < 0.001, respectively). MRI exhibited lower specificity than SPECT/CT in bone lesions (P = 0.004) and ligament/tendon lesions (P < 0.001).
  
  
  CONCLUSIONS
  SPECT/CT has MRI-comparable diagnostic performance for symptomatic lesions in ankle and foot pain patients. SPECT/CT and MRI exhibit different diagnostic specificity in different lesion types. SPECT/CT may be used as a complementary imaging method to MRI for enhancing diagnostic specificity.
authors: Department of Nuclear Medicine, Seoul National University Hospital, Seoul, Korea.
authors: Seunggyun
authors: S
authors: Ha
authors: Department of Radiology, Seoul National University Hospital, Seoul, Korea.
authors: Sung Hwan
authors: SH
authors: Hong
authors: Department of Nuclear Medicine, Seoul National University Hospital, Seoul, Korea.
authors: Jin Chul
authors: JC
authors: Paeng
authors: Department of Orthopedic Surgery, Seoul National University Hospital, Seoul, Korea.
authors: Dong Yeon
authors: DY
authors: Lee
authors: Department of Nuclear Medicine, Seoul National University Hospital, Seoul, Korea.
authors: Gi Jeong
authors: GJ
authors: Cheon
authors: Department of Nuclear Medicine, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India.
authors: Amitabh
authors: A
authors: Arya
authors: Department of Nuclear Medicine, Seoul National University Hospital, Seoul, Korea.
authors: June-Key
authors: JK
authors: Chung
authors: Department of Nuclear Medicine, Seoul National University Hospital, Seoul, Korea.
authors: Dong Soo
authors: DS
authors: Lee
authors: Department of Nuclear Medicine, Seoul National University Hospital, Seoul, Korea.
authors: Keon Wook
authors: KW
authors: Kang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000842:Ankle / Q000473:pathology*; D000843:Ankle Joint / Q000473:pathology*; D005260:Female; D005528:Foot / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000175:diagnosis* / Q000473:pathology*; D012372:ROC Curve; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013669:Technetium Tc 99m Medronate / Q000008:administration & dosage; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D055815:Young Adult
chemical_list: D013669:Technetium Tc 99m Medronate