High-resolution intracranial MRA at 7T using autocalibrating parallel imaging: initial experience in vascular disease patients

von Morze, Cornelius; Purcell, Derk D.; Banerjee, Suchandrima; Xu, Duan; Mukherjee, Pratik; Kelley, Douglas A.; Majumdar, Sharmila; Vigneron, Daniel B.

doi:10.1016/j.mri.2008.04.002

« Previous Next »Magnetic Resonance Imaging
Volume 26, Issue 10 , Pages 1329-1333, December 2008

High-resolution intracranial MRA at 7T using autocalibrating parallel imaging: initial experience in vascular disease patients

Cornelius von Morze
- Department of Radiology, University of California, San Francisco, CA, 94143-2512, USA
Derk D. Purcell
- Department of Radiology, University of California, San Francisco, CA, 94143-2512, USA
Suchandrima Banerjee
- Department of Radiology, University of California, San Francisco, CA, 94143-2512, USA
Duan Xu
- Department of Radiology, University of California, San Francisco, CA, 94143-2512, USA
Pratik Mukherjee
- Department of Radiology, University of California, San Francisco, CA, 94143-2512, USA
Douglas A. Kelley
- GE Healthcare Technologies, San Francisco, CA, 94143-2512, USA
Sharmila Majumdar
- Department of Radiology, University of California, San Francisco, CA, 94143-2512, USA
Daniel B. Vigneron
- Department of Radiology, University of California, San Francisco, CA, 94143-2512, USA
- Corresponding author. Department of Radiology, University of California, Box 2512, San Francisco, CA 94143-2512, USA. Tel.: +1 415 476 3343; fax: +1 415 514 4451.

Received 22 February 2008; received in revised form 3 April 2008; accepted 4 April 2008. published online 28 May 2008.

Abstract

Purpose

Greater spatial resolution in intracranial three-dimensional time-of-flight (TOF) magnetic resonance angiography (MRA) is possible at higher field strengths, due to the increased contrast-to-noise ratio (CNR) from the higher signal-to-noise ratio and the improved background suppression. However, at very high fields, spatial resolution is limited in practice by the acquisition time required for sequential phase encoding. In this study, we applied parallel imaging to 7T TOF MRA studies of normal volunteers and patients with vascular disease, in order to obtain very high resolution (0.12 mm³) images within a reasonable scan time.

Materials and Methods

Custom parallel imaging acquisition and reconstruction methods were developed for 7T MRA, based on generalized autocalibrating partially parallel acquisition (GRAPPA). The techniques were compared and applied to studies of seven normal volunteers and three patients with cerebrovascular disease.

Results

The technique produced high resolution studies free from discernible reconstruction artifacts in all subjects and provided excellent depiction of vascular pathology in patients.