C-arm flat detector computed tomography parenchymal blood volume imaging: the nature of parenchymal blood volume parameter and the feasibility of parenchymal blood volume imaging in aneurysmal subarachnoid haemorrhage patients

Neuroradiology. 2015 Sep;57(9):937-49. doi: 10.1007/s00234-015-1545-1. Epub 2015 May 29.

Abstract

Introduction: C-arm flat detector computed tomography (FDCT) parenchymal blood volume (PBV) measurements allow assessment of cerebral haemodynamics in the neurointerventional suite. This paper explores the feasibility of C-arm computed tomography (CT) PBV imaging and the relationship between the C-arm CT PBV and the MR-PWI-derived cerebral blood volume (CBV) and cerebral blood flow (CBF) parameters in aneurysmal subarachnoid haemorrhage (SAH) patients developing delayed cerebral ischemia (DCI).

Methods: Twenty-six patients with DCI following aneurysmal SAH underwent a research C-arm CT PBV scan using a biplane angiography system and contemporaneous MR-PWI scan as part of a prospective study. Quantitative whole-brain atlas-based volume-of-interest analysis in conjunction with Pearson correlation and Bland-Altman tests was performed to explore the agreement between C-arm CT PBV and MR-derived CBV and CBF measurements.

Results: All patients received medical management, while eight patients (31%) underwent selective intra-arterial chemical angioplasty. Colour-coded C-arm CT PBV maps were 91% sensitive and 100% specific in detecting the perfusion abnormalities. C-arm CT rPBV demonstrated good agreement and strong correlation with both MR-rCBV and MR-rCBF measurements; the agreement and correlation were stronger for MR-rCBF relative to MR-rCBV and improved for C-arm CT PBV versus the geometric mean of MR-rCBV and MR-rCBF. Analysis of weighted means showed that the C-arm CT PBV has a preferential blood flow weighting (≈ 60% blood flow and ≈ 40% blood volume weighting).

Conclusions: C-arm CT PBV imaging is feasible in DCI following aneurysmal SAH. PBV is a composite perfusion parameter incorporating both blood flow and blood volume weightings. That PBV has preferential (≈ 60%) blood flow weighting is an important finding, which is of clinical significance when interpreting the C-arm CT PBV maps, particularly in the setting of acute brain ischemia.

Keywords: C-arm flat detector computed tomography; Cerebral blood flow; MR perfusion-weighted imaging; Parenchymal blood volume; Subarachnoid haemorrhage.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blood Volume Determination
  • Cerebral Angiography / methods*
  • Cerebrovascular Circulation*
  • Feasibility Studies
  • Female
  • Hemodynamics
  • Humans
  • Image Interpretation, Computer-Assisted
  • Intracranial Aneurysm / diagnostic imaging*
  • Magnetic Resonance Angiography
  • Male
  • Middle Aged
  • Prospective Studies
  • Sensitivity and Specificity
  • Subarachnoid Hemorrhage / diagnostic imaging*
  • Tomography, X-Ray Computed / methods*