Patients who underwent flow-diverter placement for recurrent aneurysms after stent-assisted coiling between March 2015 and March 2019 were recruited. Clinical and radiographic characteristics and clinical and angiographic outcomes were retrospectively evaluated.

Among 133 patients who underwent flow-diverter insertion, 17 (male/female ratio = 5:12; mean age, 53.8 years) were treated for recurrent aneurysms after stent placement with (n = 16) or without (n = 1) coiling. Eight patients initially presented with subarachnoid hemorrhage; 7, with headache; and 2, with visual field defects. Angiographic morphology included large/giant saccular in 12 patients, dissecting in 2, fusiform in 1, traumatic pseudoaneurysm in 1, and ruptured blood blister-like aneurysm in 1. The duration between the first treatment and flow-diverter placement ranged from 2 weeks to 15 months (median, 6 months). Flow-diverter placement was successful in all cases without any complications. All patients had favorable outcomes (mRS, 0–2), without any newly appearing symptoms. Aneurysms were followed up with conventional angiography at least once in 6–18 months. Sixteen aneurysms showed complete occlusion, and 1 aneurysm was enlarged.

Results from this case series investigating flow-diverter placement for recurrent aneurysms after stent-assisted coiling suggested that the procedure is safe and effective. Further study in a larger population may be warranted.

Consecutive patients with posterior circulation aneurysms treated at 8 centers participating in the European FRED study (EuFRED) between April 2012 and January 2019 were retrospectively reviewed. Complication and radiographic and functional outcomes were evaluated.

Eighty-four patients (median age, 54 years) with 84 posterior circulation aneurysms were treated with the FRED. A total of 25 aneurysms (29.8%) had previously ruptured, even though most aneurysms were diagnosed incidentally (45.2%). The intradural vertebral artery was the most common location (50%), and saccular, the most common morphology (40.5%). The median size was 7 mm. There were 8 (9.5%) symptomatic thromboembolic and no hemorrhagic complications. Thromboembolic complications occurred mostly (90.9%) in nonsaccular aneurysms. On last follow-up at a median of 24 months, 78.2% of aneurysms were completely occluded. Functional outcome at a median of 27 months was favorable in 94% of patients. All mortalities occurred in patients with acute subarachnoid hemorrhage and its sequelae.

The largest cohort of posterior circulation aneurysms treated with the FRED to date demonstrated favorable safety and efficacy profiles of the device for this indication. Treatment in the setting of acute subarachnoid hemorrhage was strongly related to mortality, regardless of whether procedural complications occurred.

Thrombi from 85 patients who had undergone mechanical thrombectomy for acute ischemic stroke between December 2016 and March 2018 were studied retrospectively. Thrombi were examined histologically. Preinterventional imaging features, stroke subtypes, and interventional parameters were re-analyzed. Statistical analysis was performed with the Kruskal-Wallis test, Mann-Whitney U test, or Spearman correlation as appropriate.

Cardioembolic thrombi had a higher percentage of macrophages and a tendency toward more platelets than thrombi of large-artery atherosclerotic stenosis (P = .021 and .003) or the embolic stroke of undetermined source (P = .037 and .099) subtype. Thrombi prone to fragmentation required the combined use of contact aspiration and stent retrieval (P = .021) and were associated with an increased number of retrieving maneuvers (P = .001), longer procedural times (P = .001), and a higher lymphocyte content (P = .035).

We interpreted the higher macrophage and platelet content in cardioembolic thrombi compared with large-artery atherosclerotic stenosis or embolic stroke of undetermined source thrombi as an indication that the latter type might be derived from an atherosclerotic plaque rather than from an undetermined cardiac source. The extent of thrombus fragmentation was associated with a more challenging mechanical thrombectomy and a higher lymphocyte content of the thrombi. Thus, thrombus fragmentation not only might be caused by the recanalization procedure but also might be a feature of a lymphocyte-rich, difficult-to-retrieve subgroup of thrombi.

In this prespecified exploratory analysis of our prospective multi-institutional study that enrolled consecutive adult patients with anterior circulation ischemic stroke undergoing endovascular treatment from November 2017 to September 2018, we compared the following outcomes between patients with none-to-minimal (van Swieten score, 0–2) and moderate-to-severe (van Swieten score, 3–4) white matter disease using logistic regression: 90-day mRS 3–6, death, intracerebral hemorrhage, successful recanalization, and early neurologic recovery.

Of the 485 patients enrolled in the Blood Pressure after Endovascular Stroke Therapy (BEST) study, 389 had white matter disease graded (50% women; median age, 68 years; range, 58–79 years). A van Swieten score of 3–4 (n = 74/389, 19%) was associated with a higher rate of 90-day mRS of 3–6 (45% versus 18%; adjusted OR, 2.73; 95% CI, 1.34–5.93; P = .008). Although the death rate was higher in patients with van Swieten scores of 3–4 (26% versus 15%), the adjusted likelihood was not significantly different (adjusted OR, 1.14; 95% CI, 0.56–2.26; P = .710). Ordered regression revealed a shift toward worse mRS scores with increasing van Swieten scores (adjusted common OR, 3.04; 95% CI, 1.93–4.84; P < .001). No associations between white matter disease severity and intracerebral hemorrhage, successful recanalization, and early neurologic recovery were observed.

Moderate-to-severe white matter disease is associated with worse outcomes in patients undergoing endovascular treatment without a significant increase in hemorrhagic complications. Studies comparing patients with and without endovascular treatment are necessary to determine whether the benefit of endovascular treatment is attenuated with greater white matter disease.

This retrospective observational study evaluated adults (18 years of age or older) with ischemic stroke who underwent CTA and cerebral angiography sequentially between 2010 and 2018. The incidence of postcontrast acute kidney injury was determined using the baseline estimated glomerular filtration rate. The value of the baseline estimated glomerular filtration rate at which the occurrence of postcontrast acute kidney injury increased was also determined.

Postcontrast acute kidney injury occurred in 57/601 (9.5%) patients. Those with a baseline estimated glomerular filtration rate of <30 mL/min/1.73 m² showed a higher incidence of acute kidney injury. Age, chronic kidney disease, medication (nonsteroidal anti-inflammatory drugs, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, β blockers, statins, and insulin) use following contrast media exposure, and serum albumin affected the incidence of postcontrast acute kidney injury. The incidence of postcontrast acute kidney injury increased when the baseline estimated glomerular filtration rate was <43 mL/min/1.73 m².

Patients with low baseline renal function had the highest incidence of postcontrast acute kidney injury after CTA and cerebral angiography, but no fatal adverse effects were documented. Thus, patients suspected of having a stroke should be actively managed with respect to neurovascular function.

From 2009 to 2017, forty-nine patients with an ischemic stroke underwent 7T MR imaging within 3 months after symptom onset as part of a prospective intracranial vessel wall imaging study. Fourteen of these patients underwent intra-arterial treatment using thrombosuction (intra-arterial treatment group). In the intra-arterial treatment group, vessel walls were evaluated for major vessel wall changes. All patients underwent pre- and postcontrast vessel wall imaging to assess enhancing foci of the vessel wall using coregistered subtraction images. A Wilcoxon signed rank test was performed to test for differences.

In the intra-arterial treatment group, 11 of 14 patients (79%) showed vessel wall enhancement compared with 17 of 35 patients without intra-arterial treatment (49%). In the intra-arterial treatment group, more enhancing foci were detected on the ipsilateral side (n = 18.5) compared with the contralateral side (n = 3, P = .005). Enhancement was more often concentric on the ipsilateral side (n = 8) compared with contralateral side (n = 0, P = .01). No differences were found in the group without intra-arterial treatment between the number and configuration of ipsilateral and contralateral enhancing foci.

Patients with intra-arterial treatment by means of thrombosuction showed more (concentric) enhancing foci of the vessel wall ipsilateral compared with contralateral to the treated artery than the patients without intra-arterial treatment, suggesting reactive changes of the vessel wall. This finding should be taken into account when assessing vessel wall MR images in patients with stroke.

We reviewed 700 MR imaging studies performed between September 2018 and March 2019 at our institution as follow-up monitoring of coiled intracranial aneurysms. Any sizeable (>5 mm) rounded dark-signal lesions encountered were presumed to be metallic. The magnitudes and locations of such lesions were recorded. In patients with these lesions, pertinent procedural documentation was screened for devices used, including coils, microcatheters, microguidewires, and stents. Medical records were also examined to determine whether any related symptoms ensued.

Twenty patients (2.8%) exhibited a total of 25 lesions on SWI. Diameters ranged from 5 to 11 mm (median, 8 mm). All except 2 lesions were located in brain regions downstream from aneurysms, but all lesions occupied vascular territories of vessels used to place guiding catheters. Other than the Synchro 14, which was routinely deployed, no device was regularly used in patients with SWI-detectable lesions; and none of the affected patients developed focal neurologic symptoms as a consequence.

Although the origins remain unclear, distal embolization of particulate metal distal to coiled cerebral aneurysms is occasionally observed on follow-up MR imaging studies. Such lesions, however, seem to have no apparent clinical impact.

In Part I, articles reporting the reliability of CTA up to May 2018 were systematically searched and evaluated. In Part II, 11 raters independently graded 17 arterial segments in each of 50 patients with SAH for the presence of vasospasm using a 4-category scale. Raters were additionally asked to judge the presence of any moderate/severe vasospasm (≥ 50% narrowing) and whether findings would justify augmentation of medical treatment or conventional angiography ± balloon angioplasty. Four raters took part in the intraobserver reliability study.

In Part I, the systematic review revealed few studies with heterogeneous vasospasm definitions. In Part II, we found interrater reliability to be moderate at best ( ≤ 0.6), even when results were stratified according to specialty and experience. Intrarater reliability was substantial ( > 0.6) in 3/4 readers. In the per arterial segment analysis, substantial agreement was reached only for the middle cerebral arteries, and only when senior raters’ judgments were dichotomized (presence or absence of ≥50% narrowing). Agreement on the medical or angiographic management of vasospasm based on CTA alone was less than substantial ( ≤ 0.6).

The diagnosis of vasospasm using CTA alone was not sufficiently repeatable among observers to support its general use to guide decisions in the clinical management of patients with SAH.

Five hundred twenty consecutive patients with a clinical diagnosis of acute ischemic stroke (49.4% men; mean age, 72 years) who underwent CTA to evaluate large-vessel occlusion of the proximal anterior circulation were included. CTA scans were retrospectively reviewed by a consensus panel of 2 neuroradiologists. Logistic regression analysis was performed to investigate the association between several variables and missed large-vessel occlusion at the initial CTA interpretation.

The prevalence of large-vessel occlusion was 16% (84/520 patients); 20% (17/84) of large-vessel occlusions were missed at the initial CTA evaluation. In multivariate analysis, non-neuroradiologists were more likely to miss large-vessel occlusion compared with neuroradiologists (OR = 5.62; 95% CI, 1.06–29.85; P = .04), and occlusions of the M2 segment were more likely to be missed compared with occlusions of the distal internal carotid artery and/or M1 segment (OR = 5.69; 95% CI, 1.44–22.57; P = .01). There were no calcified emboli in initially correctly identified large-vessel occlusions. However, calcified emboli were present in 4 of 17 (24%) initially missed or misinterpreted large-vessel occlusions.

Several factors may have an association with missing a large-vessel occlusion on CTA, including the CTA interpreter (non-neuroradiologists versus neuroradiologists), large-vessel occlusion location (M2 segment versus the distal internal carotid artery and/or M1 segment), and large-vessel occlusion caused by calcified emboli. Awareness of these factors may improve the accuracy in interpreting CTA and eventually improve stroke outcome.