Addition of arterial spin-labelled MR perfusion to conventional brain MRI: clinical experience in a retrospective cohort study

Abstract

ObjectiveThe usage of arterial spin labelling (ASL) perfusion has exponentially increased due to improved and faster acquisition time and ease of postprocessing. We aimed to report potential additional findings obtained by adding ASL to routine unenhanced brain MRI for patients being scanned in a hospital setting for various neurological indications.DesignRetrospective.SettingLarge tertiary hospital.Participants676 patients.Primary outcomeAdditional findings from ASL sequence compared with conventional MRI.ResultsOur patient cohorts consisted of 676 patients with 257 with acute infarcts and 419 without an infarct. Additional findings from ASL were observed in 13.9% (94/676) of patients. In the non-infarct group, additional findings from ASL were observed in 7.4% (31/419) of patients, whereas in patients with an acute infarct, supplemental information was obtained in 24.5% (63/257) of patients.ConclusionThe addition of an ASL sequence to routine brain MRI in a hospital setting provides additional findings compared with conventional brain MRI in about 7.4% of patients with additional supplementary information in 24.5% of patients with acute infarct.

Arterial Spin Labeling technique and clinical applications of the intracranial compartment in stroke and stroke mimics - A case-based review

“…Studies have shown that stroke mimics can occur from 20 to 50% of patients who initially were suspected of. 62 If performed routinely as a sequence within brain imaging protocols, ASL can add value beyond stroke evaluation only, 20 which can potentially affect management. ASL can not only differentiate common stroke mimics from stroke but can also differentiate the phase of the stroke mimics, as seen with seizures and migraines.…”

“…However, the use of ASL in this setting has increased and provides added value. 20 ASL differs from DSC perfusion in major ways (Table 2). ASL may pose advantages over DSC in certain situations.…”

“…It has been shown that addition of an ASL sequence to conventional brain MRI provides additional diagnostic and supplementary information. 20…”

Technical advances paving the way for non-invasive renal perfusion MRI

“…Beyond that, clinical studies were conducted that underline the value of ASL MRI based findings and support its addition to routine clinical brain MRI protocols. 19 Meanwhile, the extension of ASL applications for perfusion imaging of abdominal organs had gained research interest. Due to its high blood flow, the kidney appeared to be an attractive candidate to begin with.…”

“…= e ,;< '( ; )* ⁄ , where TEVS is the duration of a single VS-labeling module and T 2-is T 2 of arterial blood 13. Diffusion weighting by the flow-sensitizing gradients in the labeling condition, which are absent in the control condition, will add a diffusion term19 ∆M %&''()&*+,H to the label-control difference of: ∆M %&''()&*+,H = M HI W1 − e ,-•/01 ! "#$%& X ≡ M HI • A %&''()&*+ [Eq.A2] This term depends on the b-value of the gradient-scheme, b = γ 2 • G 2 • δ 2 • (∆ − δ/3), the tissue equilibrium magnetization M0t and the tissue apparent diffusion coefficient, ADC 3&%+45 = 2.26 • 10 ,6 "" ) )…”