Sub-angiographic peripheral emboli in high resolution DWI after endovascular recanalization

Abstract

Background and aim To analyze the incidence of peripheral emboli after successful mechanical thrombectomy (MT) of intracranial large vessel occlusions (LVO). Methods We performed a prospective analysis of patients with intracranial LVO who underwent successful MT and received a 1.5 T MRI including diffusion-weighted imaging (DWI) in standard-and high-resolution as well as susceptibility-weighted imaging (SWI) on the day following the intervention. Reperfusion grade was assessed on post-thrombectomy digital subtraction angiography (DSA) using the expanded thrombolysis in cerebral infarction (eTICI) scale. Punctuate DWI lesions distal to the DWI core lesion were classified as peripheral emboli. DWI lesions outside the primary affected vascular territory were classified as emboli into new territories. Additionally, SWI and post-thrombectomy DSA were analyzed and correlated to findings on DWI. Results Twenty-eight patients undergoing successful MT met the inclusion criteria. In 26/28 patients (93%), a total of 324 embolic lesions were detected in DWI representing 2.1% of the cumulated ischemic core volume. 151 peripheral emboli were detected in standard-resolution DWI, 173 additional emboli were uncovered in high-resolution DWI. Eight out of nine patients with an eTICI 3 reperfusion had embolic lesions (29 DWI lesions). 9.6% (31/324) of peripheral emboli were observed in vascular territories not affected by the LVO. SWI lesions were observed in close proximity to 10.2% (33/324) of DWI lesions. Conclusions Peripheral emboli are frequent after MT even after complete reperfusion. These emboli occur rather in the vascular territory of the occluded vessel than in other territories. A large proportion of peripheral emboli is only detected by high-resolution DWI.

Effect of Balloon Guide Catheter Utilization on the Incidence of Sub-angiographic Peripheral Emboli on High-Resolution DWI After Thrombectomy: A Prospective Observational Study

“…Recently, we found that peripheral ischemic lesions resulting from these emboli can frequently be detected on high-resolution diffusion-weighted imaging (DWI) despite supposed complete reperfusion in DSA (10). The assessment of potentially superior treatment techniques or predictors of outcome following MT by standard outcome or imaging measures requires a large patient cohort.…”

The AF-FICIENT magnetic resonance imaging and endoscopy safety substudy: A visually guided radiofrequency balloon ablation catheter for pulmonary vein isolation

“…15 The lack of associated DWI changes suggests most if not all the SWI abnormalities were nonobstructing, whereas in the study of emboli from thrombectomy of intracranial large vessel occlusion, the SWI abnormalities were associated with larger DWI changes as well. 16 MRI J o u r n a l P r e -p r o o f susceptibility-weighted imaging may be a more sensitive test of embolism and may have value in future safety studies.…”

More Retrieval Attempts are Associated with Poorer Functional Outcome After Unsuccessful Thrombectomy

“…First, the first-pass effect could be real and the number of retrievals increases the risk of vessel injury and subsequent symptomatic intracranial hemorrhage (sICH) [19][20][21]; however, we did not observe a statistically significant increased number of sICH in our study, although this comparison K might lack statistical power due to the small number of patients in our cohort. Furthermore, each retrieval attempt is associated with risk of dispersing small distal emboli, which could lead to impaired clinical outcome [22,23]. Other possible reasons include the prolonged procedure time, the need for induction of general anesthesia and increased amounts of contrast agents [24,25].…”