DWI-ASPECTS (Diffusion-Weighted Imaging-Alberta Stroke Program Early Computed Tomography Scores) and DWI-FLAIR (Diffusion-Weighted Imaging-Fluid Attenuated Inversion Recovery) Mismatch in Thrombectomy Candidates: An Intrarater and Interrater Agreement Study.

BACKGROUND AND PURPOSE: We aimed to study the intrarater and interrater agreement of clinicians attributing DWI-ASPECTS (Diffusion-Weighted Imaging-Alberta Stroke Program Early Computed Tomography Scores) and DWI-FLAIR (Diffusion-Weighted Imaging-Fluid Attenuated Inversion Recovery) mismatch in patients with acute ischemic stroke referred for mechanical thrombectomy. METHODS: Eighteen raters independently scored anonymized magnetic resonance imaging scans of 30 participants from a multicentre thrombectomy trial, in 2 different reading sessions. Agreement was measured using Fleiss κ and Cohen κ statistics. RESULTS: Interrater agreement for DWI-ASPECTS was slight (κ=0.17 [0.14-0.21]). Four raters (22.2%) had a substantial (or higher) intrarater agreement. Dichotomization of the DWI-ASPECTS (0-5 versus 6-10 or 0-6 versus 7-10) increased the interrater agreement to a substantial level (κ=0.62 [0.48-0.75] and 0.68 [0.55-0.79], respectively) and more raters reached a substantial (or higher) intrarater agreement (17/18 raters [94.4%]). Interrater agreement for DWI-FLAIR mismatch was moderate (κ=0.43 [0.33-0.57]); 11 raters (61.1%) reached a substantial (or higher) intrarater agreement. CONCLUSIONS: Agreement between clinicians assessing DWI-ASPECTS and DWI-FLAIR mismatch may not be sufficient to make repeatable clinical decisions in mechanical thrombectomy. The dichotomization of the DWI-ASPECTS (0-5 versus 0-6 or 0-6 versus 7-10) improved interrater and intrarater agreement, however, its relevance for patients selection for mechanical thrombectomy needs to be validated in a randomized trial.

Thrombosis of venous outflows of the cavernous sinus: possible aetiology of the cortical venous reflux in case of indirect carotid-cavernous fistulas.

BACKGROUND: The presence of a cortical venous reflux (CVR) in a carotid-cavernous fistula (CCF) is well described and is considered to be a criterion for urgent treatment. This reflux is often associated with direct/traumatic CCF and the high-flow of the fistula alone explains the reflux. For indirect CCF, the pathophysiology of a CVR is unclear. METHODS: All patients treated endovascularly for an indirect CCF with a cortical venous reflux between 2003 and 2015 were included. We retrospectively analysed data focusing on whether venous outflows of the cavernous sinus would opacify or not with the local injection of contrast, in order to locate those that could explain the venous reflux. RESULTS: Twenty consecutive patients (male/female ratio, 2/3) were included in this series with a mean age of 63 years. All patients presented ocular signs and no patients showed any neurological sign secondary to the CVR. We distinguished four patterns of CVR: in the superficial middle cerebral vein (75%), in the uncal vein (15%), in the superior petrosal vein (5%) and in the inferior petrosal vein (5%). Seventy percent of the cases presented a lack of opacification in more than three venous outflows of the CS involved. Each patient received an endovascular therapy by venous approach with a success rate of 76.9% per embolisation session. Two patients (10%) presented a permanent ocular paresis and two others a transient deficit. CONCLUSIONS: CVR is directly correlated with the thrombosis of multiple venous outflows of the CS. The "non-opacification" of at least three of the CS venous outflows is necessary for the development of CVR. Such thrombosis may be explained by the combination of haemodynamic and inflammatory changes of the venous wall.

Management of multiple cerebral arteriovenous malformations in a non-pediatric population.

BACKGROUND: The occurrence of concomitant multiple cerebral arteriovenous malformations (mAVMs) is often associated with hereditary hemorrhagic telangiectasia (HHT) or craniofacial arteriovenous metameric syndrome (CAMS) and frequently occurs in the pediatric population. METHODS: Between 1995 and 2013, demographic, clinical, and angiographic data of cerebral AVMs have been prospectively collected. We retrospectively analyzed data of patients presenting multiple cerebral AVMs. RESULTS: Six patients (mean age, 44 years, male-to-female ratio, 5) presented an angiographic diagnosis of cerebral mAVMs. Only one of them was known to have a HHT. Five patients presented two cerebral AVMs and one patient had three. Three AVMs (23.1 %) presented bleeding at admission. Three patients had supratentorial mAVMs only and the three others had supra and infratentorial AVMs. Only one patient suffered from bleeding of more than one of his mAVMs with an interval of 23 years. CONCLUSIONS: For asymptomatic AVMs discovered incidentally without angiographic bleeding risk, we propose a therapeutic abstention. In case of AVM rupture and bleeding, the other "associated" AVMs (discovered through a complete angiographic assessment) should also be treated if they are not located in an eloquent area and if the treatment does not present technical difficulties. AVMs with a history of bleeding or associated to angiographic risks have to be treated more aggressively.

Multimodality Characterization of the Clot in Acute Stroke.

Aim: Current treatment of occluded cerebral vessels can be done by a variety of endovascular techniques. Sometimes, the clot responds in varying degrees to the treatment chosen. The Ex vivo characterization of the clot occluding the arteries in acute ischemic stroke can help in understanding the underlying imaging features obtained from pre-treatment brain scans. For this reason, we explored the potential of microCT when combined with electron microscopy for clot characterization. Results were compared to the clinical CT findings. Methods: 16 patients (9 males, 8 females, age range 54-93 years) who were referred to our institution for acute stroke underwent dual-source CT. Results: Clinical CT clots were seen as either iso or hyperdense. This was corroborated with micro-CT, and electron microscopy can show the detailed composition. Conclusion: MicroCT values can be used as an indicator for red blood cells-rich composition of clots. Meaningful information regarding the clot composition and modalities of embedding along the stent retrievers can be obtained through a combination of microCT and electron microscopy.

Imaging Clot Characteristics in Stroke and its Possible Implication on Treatment.

Ischemic cerebral stroke is an increasingly treatable entity due to the recent developments in intravascular clot extraction, with recent research indicating that the efficacy of the chosen thrombectomy device may be affected by the composition of the occluding clot. This literature review summarizes the results from analytical clot imaging studies, and in vitro and in vivo thrombectomies, to assess whether the choice of thrombectomy device can be optimized to the composition of the occluding clot. The literature has shown that the composition of the clot impacts its mechanical properties and interactions with the device. The existing literature with respect to imaging and current results is discussed.

Visual Field Defect Before and After Endovascular Treatment of Occipital Arteriovenous Malformations.

BACKGROUND: Occipital arteriovenous malformations (AVMs) carry a high risk of postoperative morbidity because of their anatomic relation to the visual cortex and optic radiations. Data regarding endovascular management of these lesions are scant. OBJECTIVE: To report our single-center experience with occipital AVMs, most of which were treated endovascularly, with a special interest for postoperative visual impairment. METHODS: From a prospective database, we assessed the clinical and radiological data of all patients with an occipital AVM managed between 1997 and 2018. The extension of the nidus to the primary visual cortex was assessed and correlated to the pre- and postintervention visual symptomatology. Modified Rankin Scale and visual fields (VFs) were assessed pre- and post-treatment and at the last follow-up. RESULTS: A total of 83 patients (47 males [56.6%]) with an occipital AVM were included in the study. Mean age at presentation was 33.5 ± 15.0 yr (min-max = 7-76). A total of 34 patients (41%) presented with hemorrhage related to the AVM. A total of 57 patients (68.7%) underwent endovascular treatment (EVT) alone, 20 (24.1%) underwent embolization and surgery, 3 (3.6%) underwent embolization and radiosurgery, and 3 (3.6%) were conservatively managed. A complete obliteration of the AVM was achieved in 53 patients (66.3%). A post-treatment worsening of the VF was found in 24 of the treated patients (30%), 3 patients (9%) for ruptured AVMs, and in 21 patients (46%) for unruptured AVMs. Morbidity rate was 3.7% and mortality rate was 2.5%. CONCLUSION: EVT of occipital AVM carries a non-negligible rate of complications, especially regarding visual functions.

Measurement and prediction of antimicrobial resistance in bloodstream infections by ESKAPE pathogens and Escherichia coli.

OBJECTIVES: This study aimed to evaluate a cumulative antimicrobial resistance index (ARI) as a possible key outcome measure of antimicrobial stewardship programmes (ASPs) and a tool to predict the antimicrobial resistance (AMR) trend. METHODS: Antimicrobial susceptibility for Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter spp. and Escherichia coli (ESKAPEEc) pathogens recovered from blood cultures during a 5-year period (2014-2018) was analysed to obtain a cumulative ARI. For each antibiotic tested, a score of 0, 0.5 or 1 was assigned for susceptibility, intermediate resistance or resistance, respectively, and the ARI was calculated by dividing the sum of these scores by the number of antibiotics tested. Cumulative ARIs of ESKAPEEc micro-organisms were compared and a mathematical prediction model for AMR trend was obtained. RESULTS: In total, 1858 ESKAPEEc isolates were included in the study. The cumulative ESKAPEEc mean ARI increased significantly from 0.200 ± 0.01 in 2014 to 0.276 ± 0.02 in 2018 (P < 0.001). In multivariable regression analysis, factors significantly associated with ARI ≥ 0.5 were E. faecium, K. pneumoniae, P. aeruginosa and A. baumannii infection (P < 0.001) and infection occurring after 2014 (P < 0.05). Based on the prediction model obtained, in the absence of any interventional measure, a tendency to pandrug resistance of the ESKAPEEc group could be expected in the next 8-15 years. CONCLUSION: The ARI could be a useful tool to measure the impact of ASPs on AMR. The increasing incidence of AMR among ESKAPEEc organisms underscores the needing for ASPs.

Neutrophil count predicts poor outcome despite recanalization after endovascular therapy.

OBJECTIVE: To identify early prognostic factors of poor clinical outcome in patients treated by endovascular therapy (EVT) with successful recanalization. METHODS: We reviewed our monocentric prospectively collected EVT database of patients with anterior circulation acute ischemic stroke (AIS) from January 2016 to April 2018 who had achieved successful recanalization (Thrombolysis in Cerebral Infarction score ≥ 2b) at the end of the procedure. A poor outcome was defined as a 3-month modified Rankin Scale score of ≥3. RESULTS: A total of 324 patients were included, among whom 186 (57.4%) had a poor outcome. Multivariate logistic regression indicated that age (per 10-year increase, odds ratio [OR] 1.34, 95% confidence interval [CI] 1.12-1.60), baseline NIH Stroke Scale score (per 1-unit increase, OR 1.09, 95% CI 1.04-1.15), initial infarct volume (per a log+1 increase, OR 1.34, 95% CI 1.05-1.67), blood glucose level (per a log+1 increase, OR 2.60, 95% CI 1.01-6.66), and neutrophil count (per 1,000-unit increase, OR 1.08, 95% CI 1.01-1.17) were all associated with poor clinical outcome. CONCLUSIONS: In addition to baseline severe AIS criteria, high neutrophil count and high blood glucose, known from experimental studies to be associated with downstream microvascular thromboinflammation, are independently associated with poor outcome. These findings support a deleterious role of thromboinflammation in patient recovery despite successful recanalization.

Anterior cerebral artery embolism during thrombectomy increases disability and mortality.

OBJECTIVE: During thrombectomy, thromboembolic migration in previously unaffected territory may occur and is not systematically notified. We report our data on the incidence, predictors, and clinical outcome of anterior cerebral artery emboli (ACAE). METHODS: From a prospectively collected thrombectomy database of consecutive patients with anterior circulation stroke between January 2012 and December 2016, 690 angiographic images were analyzed to assess ACAE. The primary outcome was a favorable outcome, defined as a 3 month modified Rankin Scale score of 0-2 or equal to the pre-stroke score. RESULTS: ACAE occurred in 65 patients (9.4%; 95% CI 7.2% to 11.6%). Internal carotid artery occlusion (tandem or terminal), Alberta Stroke Program Early CT Score <7, increasing number of passes, and use of stent retriever alone (compared with distal aspiration alone or combined with stent retriever) were found to be independent predictors of ACAE. Compared with patients without ACAE, patients with ACAE had lower rates, with an adjusted OR (95% CI) of 0.48 (0.25 to 0.92; P=0.027) for favorable outcome and 0.49 (0.25 to 0.96; P=0.038) for early neurologic improvement. ACAE was significantly associated with a higher mortality (adjusted OR 1.93; 95% CI 1.03 to 3.61; P=0.039) and intracranial hemorrhagic complications (adjusted OR 2.45; 95% CI 1.33 to 4.47; P=0.004). Despite a successful reperfusion modified Thrombolysis in Cerebral Infarction score of 2b-3 at the end of the procedure, a favorable outcome was reached in 30% of patients with ACAE compared with 52.4% in the other patients (OR 0.39; 95% CI 0.19 to 0.78; P=0.008). CONCLUSIONS: Procedural ACAE was not an uncommon condition, and was associated with increased mortality and disability rates, regardless of the success of reperfusion.

Unusual selection of rtA181V HBV mutants cross-resistant to adefovir following prolonged lamivudine monotherapy: report of two cases.

Development of hepatitis B virus (HBV)-resistant strains following nucleos(t)ide analogue treatment is a major concern. The A181V mutation within the reverse transcriptase (RT) of HBV has been shown to be associated with HBV resistance to adefovir dipivoxil (ADV), and its level of sensitivity to other nucleos(t)ide analogues is an important issue. This article reports two cases of chronically HBV infected patients who developed rtA181V HBV mutants following lamivudine (LAM) monotherapy. This was subsequently associated with virological breakthrough under LAM monotherapy or LAM/ADV bi-therapy, which were rescued by tenofovir disoproxil fumarate treatment. These observations suggest that rtA181V mutation may unusually emerge under LAM monotherapy, and may be associated with cross resistance to LAM and ADV, but remains sensitive to tenofovir disoproxil fumarate. Moreover, they highlight that HBV sequence analysis is an essential tool to optimize therapeutic management of HBV chronic infection in clinical practice in order to choose the appropriate nucleos(t)ide analogues.

Fulminant hepatitis B associated with a specific insertion in the basal core promoter region of hepatitis B virus DNA after immunosuppressive treatment.

We report a case of hepatitis B virus reactivation that occurred after immunosuppressive treatment in a hepatitis B surface antigen-negative patient with detectable antibodies to hepatitis B core antigen and hepatitis B surface antigen. Sequence analysis revealed an 11-bp insertion in the core promoter region of hepatitis virus DNA, creating a novel hepatocyte nuclear factor-1 binding site. This led to enhanced viral replication and fulminant hepatitis.