title: Intravertebral cleft sign on fat-suppressed contrast-enhanced MR: correlation with cement distribution pattern on percutaneous vertebroplasty.
abstract: OBJECTIVE
  Filling intravertebral clefts during percutaneous vertebroplasty (PVP) is considered to be important for optimal pain control. It is often difficult to detect clefts on non-contrast MR and some fractures show a solid pattern distribution of injected cement without a cleft sign on non-contrast MR. In this study, we evaluated usefulness of fat-suppressed contrast-enhanced MR to predict a solid pattern distribution of injected cement on PVP.
  
  
  METHODS
  Twenty-six patients with 35 vertebral compression fractures due to osteoporosis were studied. We performed sagittal T1-weighted, T2-weighted and fat-suppressed contrast-enhanced T1-weighted images prior to PVP. First we evaluated the presence of fluid-filled or gas-containing clefts on non-contrast MR. Next we evaluated contrast-enhanced MR of the same vertebrae for the presence of cleft-shaped unenhanced areas within the diffuse enhancement area. We correlated MR findings with cement distribution patterns of injected cement.
  
  
  RESULTS
  Based on MR findings, 35 osteoporotic fractures were divided into 3 types. Type 1 (11 fractures, 31%): There were no clefts on non-contrast MR and no unenhanced areas on contrast-enhanced MR; Type 2 (13, 37%): There were no clefts on non-contrast MR but there were unenhanced areas on contrast-enhanced MR; Type 3 (13, 37%): There were clefts on non-contrast MR and unenhanced areas on contrast-enhanced MR. Of 35 osteoporotic fractures, thirteen vertebral fractures (37%) were noted to contain clefts on non-contrast MR, while 24 vertebral fractures (69%) contained unenhanced areas on contrast-enhanced MR. Cement distributed as a solid pattern within clefts or unenhanced areas in all fractures with them.
  
  
  CONCLUSIONS
  Fat-suppressed contrast-enhanced MR is useful to predict a solid pattern distribution of injected cement prior to PVP.
authors.affiliation: Department of Radiology, St Luke's International Hospital, Chuo-ku, Tokyo, Japan. okamasaki_1213@yahoo.com
authors.forename: Masaki
authors.initials: M
authors.lastname: Oka
authors.forename: Masaki
authors.initials: M
authors.lastname: Matsusako
authors.forename: Nobuo
authors.initials: N
authors.lastname: Kobayashi
authors.forename: Akihiro
authors.initials: A
authors.lastname: Uemura
authors.forename: Yuji
authors.initials: Y
authors.lastname: Numaguchi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001466:Barium Sulfate / Q000008:administration & dosage; D001843:Bone Cements / Q000627:therapeutic use; D003287:Contrast Media / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007278:Injections, Spinal; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging* / Q000293:injuries* / Q000601:surgery; D008279:Magnetic Resonance Imaging; D008297:Male; D010024:Osteoporosis / Q000145:classification / Q000150:complications / Q000000981:diagnostic imaging / Q000628:therapy; D019904:Polymethyl Methacrylate / Q000627:therapeutic use; D011856:Radiographic Image Enhancement; D016103:Spinal Fractures / Q000145:classification / Q000000981:diagnostic imaging* / Q000209:etiology / Q000628:therapy; D013223:Statistics as Topic
chemical_list: D001843:Bone Cements; D003287:Contrast Media; D001466:Barium Sulfate; D019904:Polymethyl Methacrylate