Microhemorrhagic transformation of ischemic lesions on T2*-weighted magnetic resonance imaging after Pipeline embolization device treatment

Abstract

OBJECTIVE The authors sought to demonstrate that hemorrhagic transformation of ischemic lesions is the main cause of delayed intracerebral hemorrhage (ICH) after Pipeline embolization device (PED) treatment and to estimate the rate of hemorrhagic transformation of new postprocedure ischemic lesions. METHODS Patients who underwent PED placement (PED group) from November 2015 to March 2017 or stent-mediated embolization (EN group) from December 2010 to October 2015 were retrospectively analyzed. Pre- and postprocedural MR images and 6-month follow-up MR images for each patient were scored for the presence of postprocedural bland ischemic and hemorrhagic lesions using diffusion-weighted MRI (DWI) and T2*-weighted MRI (T2*WI), respectively. RESULTS The PED group comprised 28 patients with 30 intracranial aneurysms, and the EN group comprised 24 patients with 27 intracranial aneurysms. The mean number of ischemic lesions on DWI 1 day postprocedure was higher in the PED group than in the EN group (5.2 vs 2.7, p = 0.0010). The mean number of microbleeds detected on T2*WI 6 months postprocedure was higher in the PED group than in the EN group (0.6 vs 0.15, p = 0.028). A total of 36.7% of PED-treated patients exhibited new microbleeds on T2*WI at 6 months postprocedure, with at least 77.8% of these lesions representing hemorrhagic transformations of the new ischemic lesions observed on day 1 postprocedure. The rate of adjunctive coil embolization (27.3% vs 0.0%, p = 0.016) and the mean number of ischemic lesions observed 1 day postprocedure (6.6 vs 4.3, p = 0.020) were predictors of subsequent microbleeds in the PED group. CONCLUSIONS New microbleeds detected using T2*WI at 6 months postprocedure were more common after PED treatment than after stent-mediated embolization. Approximately three-quarters of these lesions were hemorrhagic transformations of new ischemic lesions observed on day 1 postprocedure. Prevention of intraprocedural or postprocedural infarcts is necessary to reduce the risk of hemorrhagic complications following PED placement.

Risk Factor Analysis of Delayed Intracerebral Hemorrhage After Coil Embolization of Unruptured Cerebral Aneurysms

“…There are several studies regarding d-ICH after endovascular treatment of an UIA, but most were linked to flow diverters (11)(12)(13)(14)(15)(16)(17). Based upon our experience, d-ICH can occur not only in cases with a flow diverter but also in coiling cases, as antiplatelet maintenance is necessary in both situations (especially when a stent is used in coiling cases).…”

Treatment of acute thrombosis during stent-assisted coil embolization of ruptured proximal posterior inferior cerebellar artery aneurysm

“…The Neuroform EZ stent was designed for the treatment of intracranial wide-necked and fusiform aneurysms. [ 10 ] The stent not only renders mechanical and hemodynamic benefits for aneurysm occlusion by preventing and repairing coil protrusion into the parent artery but also reduces and modifies the aneurysm inflow pattern adequately. Moreover, it is an excellent option for the intracranial aneurysms located at the bifurcation.…”

Diffusion weighted image documented cerebral ischemia in the postprocedural period following pipeline embolization device with shield technology treatment of unruptured intracranial aneurysms: a prospective, single center study

“…In the systemic review and meta-analysis by Bond et al , the rate of postprocedural DWI documented ischemic lesions was 45%, 44%, 43%, and 67% after simple coiling, balloon assisted coiling, stent assisted coiling, and flow diversion, respectively 23. Single center studies evaluating silent cerebral ischemia after intracranial aneurysm treatment with the PED reported an asymptomatic cerebral ischemia rate of 50.9–90% 4–11. These studies reported an increased risk of post-PED treatment silent cerebral ischemia with female gender,4 aneurysm size ≥10 mm,5 and age ≥60 6…”

“…We hypothesized that management of intracranial aneurysms with the PED-Shield is associated with a lower rate of postprocedural, diffusion weighted imaging (DWI) documented cerebral ischemia than previously reported with the PED 4–11. Hence the purpose of this prospective study was to determine the incidence of cerebral ischemia on postprocedural DWI following PED-Shield treatment of intracranial aneurysms in a single institution cohort of consecutive patients.…”

“…However, flow diversion is not without complications, and despite the routine use of antiplatelet medications and preprocedural assessment of individual responses to antiplatelet medication, postprocedural cerebral ischemia remains the most common complication of flow diversion. Acute ischemic stroke and silent cerebral infarctions following PED treatment have been reported at a rate of 2.6–4.7%1–3 and 50.9–90%,4–11 respectively. The association of the latter with delayed intracerebral hemorrhage,5 11 cognitive decline, and vascular dementia remains unclear 12 13…”