Article Text

Letter
A novel use of arterial spin labelling MRI to demonstrate focal hypoperfusion in individuals with posterior cortical atrophy: a multimodal imaging study
  1. Manja Lehmann1,
  2. Andrew Melbourne2,
  3. John C Dickson3,
  4. Rebekah M Ahmed1,
  5. Marc Modat2,
  6. M Jorge Cardoso2,
  7. David L Thomas1,4,
  8. Enrico De Vita4,5,
  9. Sebastian J Crutch1,
  10. Jason D Warren1,
  11. Colin J Mahoney1,
  12. Jamshed Bomanji3,
  13. Brian F Hutton3,
  14. Nick C Fox1,
  15. Xavier Golay4,
  16. Sebastien Ourselin2,
  17. Jonathan M Schott1
  1. 1 Dementia Research Centre, UCL Institute of Neurology, London, UK
  2. 2 Translational Imaging Group, Centre for Medical Image Computing, University College London, London, UK
  3. 3 Institute of Nuclear Medicine, University College London Hospitals, London, UK
  4. 4 Lysholm Department of Neuroradiology, National Hospital for Neurology and Neurosurgery, London, UK
  5. 5 Neuroradiological Academic Unit, Brain Repair & Rehabilitation, UCL Institute of Neurology, London, UK
  1. Correspondence to Dr Jonathan M Schott, Dementia Research Centre, UCL Institute of Neurology, 8-11 Queen Square, London WC1N 3BG, UK; j.schott{at}ucl.ac.uk

Statistics from Altmetric.com

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

Introduction

Posterior cortical atrophy (PCA) is a rare neurodegenerative syndrome, typically due to Alzheimer pathology, characterised by impairments in higher-order visual function and other parieto-occipital skills.1 MRI measures of atrophy and 18F-labelled fluorodeoxyglucose (FDG) positron emission tomography (PET) measures of glucose metabolism typically show posterior cortical deficits broadly mirroring the focal cognitive deficits.1 By contrast, amyloid PET studies demonstrate that fibrillar amyloid is widely deposited across the cortex.2 Arterial spin labelling (ASL) is an MRI methodology that uses endogenous arterial blood water as a tracer to quantify cerebral blood flow (CBF).3 We aimed to assess the ability of ASL to detect patterns of reduced CBF in PCA, and to compare these results with those from other imaging modalities.

Methods

Five patients fulfilling clinical diagnostic criteria for PCA,4 and five controls attended for three scanning visits usually on consecutive days. On day 1, MRI scans were acquired on a 3 T Siemens TIM Trio scanner with a 32-channel phased array head-coil. Sequences included a sagittal three-dimensional (3D) MPRAGE T1-weighted volumetric scan (acquisition time 9 min 23 s, TE/TR/TI=2.9/2200/900 ms, dimensions 256×256×208, voxel size 1.1×1.1×1.1 mm), and coronal T2 fluid-attenuated inversion recovery (TE/TR/TI=87/9000/2500 ms, voxel size 0.9375×0.9375×5 mm). Perfusion data were acquired using pulsed ASL (FAIR Q2TIPS) with an 8-segment, background-suppressed 3D GRASE imaging readout5 (acquisition time 6 min 40 s, TI1/2=800/2000 ms, voxel size 3.8×3.8×4.0 mm, refocusing pulse flip angle 130°, five repetitions). A set of three saturation recovery images (TR=1,2,5 s) with the same readout module was also acquired to generate tissue M0 and T1 maps for CBF quantification. On day 2, each participant underwent a 10 min PET scan …

View Full Text

Supplementary materials

  • Supplementary Data

    This web only file has been produced by the BMJ Publishing Group from an electronic file supplied by the author(s) and has not been edited for content.