title: Diffusion-Weighted Imaging for Pretreatment Evaluation and Prediction of Treatment Effect in Patients Undergoing CT-Guided Injection for Lumbar Disc Herniation.
abstract: OBJECTIVE
  To determine whether a change in apparent diffusion coefficient (ADC) value could predict early response to CT-guided Oxygen-Ozone (O2-O3) injection therapy in patients with unilateral mono-radiculopathy due to lumbar disc herniation.
  
  
  METHODS
  A total of 52 patients with unilateral mono-radiculopathy received a single intradiscal (3 mL) and periganglionic (5 mL) injection of an O2-O3 mixture. An ADC index of the involved side to the intact side was calculated using the following formula: pre-treatment ADC index = ([ADC involved side - ADC intact side] / ADC intact side) × 100. We analyzed the relationship between the pre-treatment Oswestry Disability Index (ODI) and the ADC index. In addition, the correlation between ODI recovery ratio and ADC index was investigated. The sensitivity and specificity of the ADC index for predicting response in O2-O3 therapy was determined.
  
  
  RESULTS
  Oswestry Disability Index and the ADC index was not significantly correlated (r = -0.125, p = 0.093). The ADC index and ODI recovery ratio was significantly correlated (r = 0.819, p < 0.001). When using 7.10 as the cut-off value, the ADC index obtained a sensitivity of 86.3% and a specificity of 82.9% for predicting successful response to therapy around the first month of follow-up.
  
  
  CONCLUSIONS
  This preliminary study demonstrates that the patients with decreased ADC index tend to show poor improvement of clinical symptoms. The ADC index may be a useful indicator to predict early response to CT-guided O2-O3 injection therapy in patients with unilateral mono-radiculopathy due to lumbar disc herniation.
authors.affiliation: Department of Radiology, Affiliated Hospital of Chengdu University, Chengdu, Sichuan Province 610000, China.
authors.forename: Xiang-Ke
authors.initials: XK
authors.lastname: Niu
authors.affiliation: Sichuan Key Laboratory of Medical Imaging and Department of Radiology, Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan Province 637000, China.
authors.forename: Anup
authors.initials: A
authors.lastname: Bhetuwal
authors.affiliation: Sichuan Key Laboratory of Medical Imaging and Department of Radiology, Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan Province 637000, China.
authors.forename: Han-Feng
authors.initials: HF
authors.lastname: Yang
mesh_terms: D000328:Adult; D000368:Aged; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000175:diagnosis* / Q000628:therapy*; D008159:Lumbar Vertebrae / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000627:therapeutic use; D010126:Ozone / Q000627:therapeutic use; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D010126:Ozone; D010100:Oxygen
keywords: Apparent diffusion coefficient; CT-guided spinal injections; Diffusion weighted image; Dorsal root ganglion; Periradicular injection