title: MR-guided direct arthrography of the hip.
abstract: OBJECTIVE
  To develop an MR-guided technique for direct magnetic resonance arthrography (DMRA) of the hip using a conventional 1.5 Tesla (T) MRI scanner.
  
  
  METHODS
  Interactive versions of standard single-shot fast spin echo, coherent gradient echo, and fully balanced steady-state free precession sequences were developed, together with the ability to operate the scanner from within the magnet room. Initial optimization was performed using ex vivo animal joints. After informed consent, five patients underwent DMRA using dilute gadolinium as the contrast medium.
  
  
  RESULTS
  The procedure was successful in all five patients and diagnostic quality MR arthrography studies were obtained in all cases. The time taken from the initial placement of skin marker to the introduction of contrast medium reduced with successive patients: 26, 22, and 19 min with the final two studies taking 13 min each.
  
  
  CONCLUSIONS
  This work demonstrates the feasibility of performing DMRA using MR guidance, avoiding the need for X-ray fluoroscopy facilities but exploiting the available imaging performance of a high-field closed-bore MR system. The use of an in room control and display system together with interactive fluoroscopic imaging sequences simplifies the positioning of the needle and allows rapid confirmation of an intra-articular injection.
authors.affiliation: Department of Radiology, Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom. mjg40@radiol.cam.ac.uk
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Graves
authors.forename: Suzanne
authors.initials: S
authors.lastname: Wakely
authors.forename: Philip W
authors.initials: PW
authors.lastname: Bearcroft
authors.forename: Richard T
authors.initials: RT
authors.lastname: Black
authors.forename: Elzare
authors.initials: E
authors.lastname: van Rooyen
authors.forename: Edmund
authors.initials: E
authors.lastname: Soh
authors.forename: David J
authors.initials: DJ
authors.lastname: Lomas
mesh_terms: D000818:Animals; D016477:Artifacts; D003287:Contrast Media / Q000008:administration & dosage; D005240:Feasibility Studies; D019786:Gadolinium DTPA / Q000008:administration & dosage; D006621:Hip Joint / Q000473:pathology*; D006801:Humans; D007270:Injections, Intra-Articular; D053783:Magnetic Resonance Imaging, Interventional / Q000379:methods*; D009339:Needles; D034561:Sheep, Domestic; D013552:Swine
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA