High resolution, magnetization transfer saturation, variable flip angle, time-of-flight mr a in the detection of intracranial vascular stenoses

Angela Dagirmanjian, Jeffrey S. Ross, Nancy Obuchowski, Jonathan S. Lewin, Jean A. Tkach, Paul M. Ruggieri, Thomas J. Masaryk

Research output: Contribution to journalArticlepeer-review

53 Scopus citations


Objective: Factors that restrict 3D TOF MRA are limited resolution, saturation of flow, and degree of background suppression. We evaluated MRA for intracranial stenoses by using a 3D TOF technique that minimizes these factors. Materials and Methods: Twenty-nine patients underwent MRA and intraarterial digital subtraction angiography (DSA). The MRA studies were performed on a 1.5 T Siemens SP 4000 system. Integrated techniques applied to the conventional 3D TOF acquisition included the following: (a) 256 x 256 matrix with a 140 mm FOV and 0.9 mm slice thickness, yielding a 0.54 x 0.54 x 0.9 mm3 voxel; (b) tilted optimized nonsaturating excitation (TONE); and (c) magnetization transfer saturation (MTS). The intraarterial DSA was performed on a Siemens Angiostar system with a 1,024 x 1,024 noninterpolated matrix. The MRAs were reviewed by two neuroradiologists. Two hundred seventy-seven vessels were evaluated for a total of 806 segments. Vessel segments were evaluated with a 5 point scale. Results: The estimated accuracy of MRA for detecting stenosis over all intracranial vessel segments was 0.88 ± 0.03 and 0.89 ± 0.02 for the two readers, respectively. The estimated accuracy ranged from 0.94 ± 0.02 and 0.93 ± 0.02 for detecting internal carotid artery stenosis by the two readers, respectively, to 0.65 ± 0.17 and 0.71 ± 0.15 for detecting distal vertebral artery stenosis. In vessels determined by catheter angiography to be stenosis-free, reader confidence at the proximal versus distal segments was similar for the internal carotid, basilar, and posterior cerebral arteries. However, for the anterior and middle cerebral arteries, one or both readers were more confident in diagnosing the proximal segment. Conclusion: High resolution MTS TONE 3D TOF MRA is an accurate technique for the screening of medium and large vessel intracranial stenoses.

Original languageEnglish (US)
Pages (from-to)700-706
Number of pages7
JournalJournal of computer assisted tomography
Issue number5
StatePublished - 1995
Externally publishedYes


  • Brain, blood flow
  • Magnetic resonance imaging angiography (MRA)
  • Magnetic resonance imaging, techniques
  • Magnetization transfer

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging


Dive into the research topics of 'High resolution, magnetization transfer saturation, variable flip angle, time-of-flight mr a in the detection of intracranial vascular stenoses'. Together they form a unique fingerprint.

Cite this