title: Impact of coil design on the contrast-to-noise ratio, precision, and consistency of quantitative cartilage morphometry at 3 Tesla: a pilot study for the osteoarthritis initiative.
abstract: Phased-array (PA) coils generally provide higher signal-to-noise ratios (SNRs) than quadrature knee coils. In this pilot study for the Osteoarthritis Initiative (OAI) we compared these two types of coils in terms of contrast-to-noise ratio (CNR), precision, and consistency of quantitative femorotibial cartilage measurements. Test-retest measurements were acquired using coronal fast low-angle shot with water excitation (FLASHwe) and coronal multiplanar reconstruction (MPR) of sagittal double-echo steady state with water excitation (DESSwe) at 3T. The precision errors for cartilage volume and thickness were <or=2.6% for the quadrature coil and <or=2.3% for the PA coil with FLASHwe, and <or=2.3%/<or=2.5% with DESSwe. The precision for aggregate medial and lateral cartilage measures was significantly higher than that for single plates, independently of coil and sequence. The PA coil measurements did not always fully agree with the quadrature coil measurements, and some differences were significant. The higher CNR of the PA coil did not translate directly into improved precision of cartilage measurement; however, summing up cartilage plates within the medial and lateral compartment reduced precision errors.
authors.affiliation: Institute of Anatomy and Musculoskeletal Research, Paracelsus Medical University, Salzburg, Austria, and Center for Primary Care and Prevention, Memorial Hospital of Rhode Island, Pawtucket, USA. felix.eckstein@pmu.ac.at
authors.forename: Felix
authors.initials: F
authors.lastname: Eckstein
authors.forename: Manuela
authors.initials: M
authors.lastname: Kunz
authors.forename: Martin
authors.initials: M
authors.lastname: Hudelmaier
authors.forename: Rebecca
authors.initials: R
authors.lastname: Jackson
authors.forename: Joseph
authors.initials: J
authors.lastname: Yu
authors.forename: Charles B
authors.initials: CB
authors.lastname: Eaton
authors.forename: Erika
authors.initials: E
authors.lastname: Schneider
mesh_terms: D000368:Aged; D002358:Cartilage, Articular / Q000473:pathology*; D016022:Case-Control Studies; D018450:Disease Progression; D004867:Equipment Design; D005260:Female; D005269:Femur / Q000473:pathology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000295:instrumentation*; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000473:pathology*; D010865:Pilot Projects; D013977:Tibia / Q000473:pathology