Article Text
Abstract
Background and Purpose Intracranial arteriovenous malformations (AVMs) can lead to serious complications, such as hemorrhagic stroke, seizures, and neurological deficits, if left undiagnosed. Arterial Spin Labeling (ASL) is a non-invasive MR imaging technique that uses magnetically labeled arterial blood as an endogenous tracer to visualize cerebral blood flow. This study aims to evaluate the sensitivity and specificity of ASL compared to conventional MRI sequences for detecting intracranial AVMs in patients with Hereditary Hemorrhagic Telangiectasia (HHT).
Materials and Methods In this retrospective study, we examined a cohort of 42 patients with definite or probable HHT by Curacao criteria who had undergone brain MRI/MRA and digital subtraction angiography (DSA) within 365 days of each other. From this cohort, 6 patients were excluded on the basis of having both negative MRI and DSA examinations. All MRIs contained conventional sequences as well as ASL perfusion and were retrospectively reviewed by two blinded fellowship-trained neuroradiologists. These readers evaluated each MR imaging study as a whole and recorded the total number of AVMs identified for each patient as well as on which sequences the AVMs were visible (3D-T1-weighted post-gadolinium, 2D-T1-weighted post-gadolinium, time-of-flight MRA, T2-weighted, SWI, and ASL). The cerebral DSA images for all 41 patients were reviewed by a fellowship-trained neurointerventional radiologist who determined and recorded the total numbers of intracranial AVMs visible on DSA. The sensitivity of ASL and conventional MRI sequences were each respectively calculated using DSA as the gold standard.
Results Out of 36 patients with positive MRI findings of AVM, 2 were negative on DSA. Of these 2 patients, both demonstrated positive ASL findings and 1 showed positive conventional MRI findings. The remaining 34 patients had a total of 57 intracranial AVMs, with 51 of these AVMs demonstrating increased signal on ASL and 43 detected by conventional MRI sequences. The sensitivity for ASL was 89.5% (51/57), significantly higher than the 75.4% (43/57) sensitivity for conventional MRI (p=0.049).
Conclusions Our findings underscore the incremental value of ASL in addition to conventional MRI sequences as a screening tool in the detection of brain AVMs in patients with HHT. ASL was more sensitive than conventional contrast-enhanced MRI alone, potentially improving diagnostic accuracy in this patient population with many small AVMs. These findings further highlight the need for further research to explore the benefits of integrating ASL sequences into the initial evaluation and routine follow-up of patients with sporadic and HHT-related brain AVMs.
Disclosures W. Han: None. A. Alyafaie: None. Y. Li: None. S. Hetts: None.