The purpose of this study is to evaluate feasibility, image quality (IQ), and accuracy of noncontrast hybrid arterial spin labeling (NoHASL) magnetic resonance angiography (MRA) compared with time of flight (TOF) MRA and contrast-enhanced (CE) MRA in patients with known/suspected cerebrovascular ischemia.
Thirty inpatients were imaged at 1.5 T. Two neuroradiologists assessed 630 intracranial arterial segments for IQ (1, nondiagnostic; 3, satisfactory for diagnosis; and 5, excellent). Hemodynamically significant stenosis (>50%) was assessed against all combined techniques as reference.
The NoHASL MRA IQ was diagnostic (3.32 ± 0.86) but affected by signal to noise ratio and spatial resolution limitations and significantly inferior to TOF (3.48 ± 0.68) and CE MRA (3.44 ± 0.78) (P < 0.0001 in both comparisons). Fourteen (2.2%) of 630 segments had hemodynamically significant stenoses at the reference standard. Sensitivity/specificity was not significantly different between techniques: NoHASL MRA, 67.9%/90.0%; TOF MRA, 67.9%/97.7%; and CE MRA, 50.0%/98.7%.
The NoHASL MRA is feasible, with diagnostic quality imaging of proximal intracranial vessels. Low disease prevalence limited the assessment of technique accuracy.
From the *Radiology, Austin Health; †Radiology and ‡Surgery, The University of Melbourne, Melbourne, Australia; §Siemens Healthcare, Chicago, IL; ∥Advanced Clinical Imaging Technology, Siemens Healthcare AG, Lausanne, Switzerland; ¶Neurology, Austin Health; #Department of Neurosciences, Eastern Health Clinical School, Melbourne, Australia; **Radiology, NorthShore University Health System, Evanston, IL; and ††Radiology, Pritzker School of Medicine, University of Chicago, Chicago, IL.
Received for publication March 5, 2017; accepted March 20, 2017.
Correspondence to: Ruth P. Lim, MBBS (Hons), MMed, MS, FRANZCR, Austin Hospital, 145 Studley Rd, Heidelberg, Victoria 3084, Australia (e-mail: email@example.com).
E.T. and R.P.L. contributed equally to the work.
Presentations: Poster Presentation at the Annual Meeting of the International Society of Magnetic Resonance in Medicine 2016, Singapore.
No funding support was received for this study. S.G. and D.P. are employees of Siemens Healthcare, the manufacturer of the magnetic resonance imaging system used in this study. The other authors (who are not Siemens employees) had control of the data and information that might present a conflict of interest for the employee authors. R.P.L. has a grant pending for an investigator-initiated study from Boehringer-Ingelheim for an unrelated study investigating the effect of empagliflozin on the kidneys in diabetic patients.