title: A low-power high-sensitivity single-chip receiver for NMR microscopy.
abstract: In this paper, we present a fully-integrated receiver for NMR microscopy applications manufactured in a 0.13μm CMOS technology. The design co-integrates a 10-turn planar detection coil together with a complete quadrature, low-IF downconversion receiver on a single chip, which operates from a single 1.5V supply with a total power dissipation of 18mW. The detector's measured time-domain spin sensitivity is 3×10(13)(1)Hspins/Hz at 7T. Additionally, the paper discusses two important aspects of NMR microscopy using planar detection coils: the link between the detection coil's spin sensitivity and the achievable image SNR and the correction of image artifacts induced by the inhomogeneous sensitivity profile of planar detection coils. More specifically, we derive analytical expressions for both the theoretical image SNR as a function of the coil's spin sensitivity and the sensitivity correction for a known coil sensitivity profile in CTI MR imaging experiments. Both expressions are validated using measured data in the imaging section of the paper. Thanks to the improved spin sensitivity of the utilized integrated receiver chip compared to a previously presented design, we were able to obtain sensitivity corrected images in a 7T spectroscopy magnet with isotropic resolutions of 9.6μm and 5μm with single-shot SNRs of 37 and 15 in relatively short imaging times of 4.4h and 24h, respectively.
authors.affiliation: University of Ulm, Institute of Microelectronics, Albert-Einstein-Allee 43, D-89081 Ulm, Germany; Ecole Polytechnique Federale de Lausanne (EPFL), Institute of Microengineering, Station 17, CH-1015 Lausanne, Switzerland. Electronic address: jens.anders@uni-ulm.de.
authors.forename: Jens
authors.initials: J
authors.lastname: Anders
authors.affiliation: University of Ulm, Institute of Microelectronics, Albert-Einstein-Allee 43, D-89081 Ulm, Germany.
authors.forename: Jonas
authors.initials: J
authors.lastname: Handwerker
authors.affiliation: University of Ulm, Institute of Microelectronics, Albert-Einstein-Allee 43, D-89081 Ulm, Germany.
authors.forename: Maurits
authors.initials: M
authors.lastname: Ortmanns
authors.affiliation: Ecole Polytechnique Federale de Lausanne (EPFL), Institute of Microengineering, Station 17, CH-1015 Lausanne, Switzerland.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Boero
mesh_terms: D000669:Amplifiers, Electronic; D011211:Electric Power Supplies; D004582:Electronics, Medical / Q000295:instrumentation; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008279:Magnetic Resonance Imaging / Q000295:instrumentation*; D009682:Magnetic Resonance Spectroscopy / Q000295:instrumentation*; D008853:Microscopy / Q000295:instrumentation*; D008904:Miniaturization; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D012666:Semiconductors; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*
keywords: CMOS; Integrated circuits; MRI; Micro-MRI; NMR microscopy; Planar microcoils; Sensitivity correction; Signal-to-noise ratio