L'imagerie joue un rôle central à la phase aiguë de l'accident vasculaire cérébral ischémique (AVCi), permettant le diagnostic positif, le diagnostic différentiel et la sélection des patients ...éligibles aux thérapeutiques visant à rétablir un flux sanguin adéquat vers le tissu cérébral ischémié afin de limiter les lésions irréversibles du parenchyme cérébral, favoriser la récupération fonctionnelle, limiter la mortalité et le risque de récidive.
Avec l'avènement des techniques d'imagerie avancée, la progression des connaissances sur la physiopathologie de l'ischémie cérébrale et le développement des techniques de revascularisation mécanique, l'imagerie sert désormais à évaluer à l'échelle individuelle les paramètres de viabilité tissulaire, de perfusion et de collatéralité, le niveau d'occlusion, et renseigne sur le risque hémorragique, permettant ainsi de maximiser les opportunités thérapeutiques.Ces changements de paradigme ont redéfini les points clés de l'acquisition et de l'interprétation de l'imagerie chez un patient suspect d'AVC, allant au-delà du concept, restant valable, de « time is brain ».
Nous verrons dans cet article les points clés qui guident la stratégie d'imagerie à la phase aiguë de l'AVCi, visant à établir le diagnostic positif, éliminer les diagnostics différentiels et guider les thérapeutiques urgentes (figs 1-4), 1-15.
Background and purpose
In patients with acute ischemic stroke (AIS) treated with endovascular therapy (EVT), the association of pre-existing cerebral small vessel disease (cSVD) with symptomatic ...intracerebral hemorrhage (sICH) remains controversial. We tested the hypothesis that the presence of cerebral microbleeds (CMBs) and their burden would be associated with sICH after EVT of AIS.
Methods
We conducted a retrospective study combining cohorts of patients that underwent EVT between January 1st 2015 and January 1st 2020. CMB presence, burden, and other cSVD markers were assessed on a pre-treatment MRI, evaluated independently by two observers. Primary outcome was the occurrence of sICH.
Results
445 patients with pretreatment MRI were included, of which 70 (15.7%) demonstrated CMBs on baseline MRI. sICH occurred in 36 (7.6%) of all patients. Univariate analysis did not demonstrate an association between CMB and the occurrence of sICH (7.5% in CMB+ group vs 8.6% in CMB group,
p
= 0.805). In multivariable models, CMBs’ presence was not significantly associated with increased odds for sICH (-aOR- 1.19; 95% CI 0.43–3.27,
p
= 0.73). Only ASPECTs (aOR 0.71 per point increase; 95% CI 0.60–0.85,
p
< 0.001) and collaterals status (aOR 0.22 for adequate versus poor collaterals; 95% CI 0.06–0.93,
p
0.019) were independently associated with sICH.
Conclusion
CMB presence and burden is not associated with increased occurrence of sICH after EVT. This result incites not to exclude patients with CMBs from EVT. The risk of sICH after EVT in patients with more than10 CMBs will require further investigation.
Registration
Registration-URL:
http://www.clinicaltrials.gov
; Unique identifier: NCT01062698.
Background and purpose
To determine the influence of the cerebral small vessel disease (SVD) burden on collateral recruitment in patients treated with mechanical thrombectomy (MT) for anterior ...circulation acute ischemic stroke (AIS).
Methods
Patients with AIS due to large vessel occlusion (LVO) from the Thrombectomie des Artères Cérébrales (THRACE) trial and prospective cohorts from 2 academic comprehensive stroke centers treated with MT were pooled and retrospectively analyzed. Collaterals’ adequacy was assessed using the American Society of Interventional and Therapeutic Radiology/Society of Interventional Radiology (ASITN/SIR) score on initial digital subtraction angiography and dichotomized as good (3,4) versus poor (0–2) collaterals. The SVD burden was rated with the global SVD score on MRI. Multivariable logistic regression analyses were used to determine relationships between SVD and ASITN/SIR scores.
Results
A total of 312 participants were included (53.2% males, mean age 67.8 ± 14.9 years). Two hundred and seven patients had poor collaterals (66.4%), and 133 (42.6%) presented with any SVD signature. In multivariable analysis, patients demonstrated worse leptomeningeal collaterality with increasing SVD burden before and after adjustment for SVD risk factors (adjusted odds ratio aOR 0.69; 95%CI 0.52–0.89 and aOR 0.66; 95%CI 0.5–0.88, respectively). Using individual SVD markers, poor collaterals were significantly associated with the presence of lacunes (aOR 0.40, 95% CI 0.20–0.79).
Conclusion
Our study provides evidence that in patients with AIS due to LVO treated with MT, the burden of SVD assessed by pre-treatment MRI is associated with poorer recruitment of leptomeningeal collaterals.
Objectives
We tested whether FLAIR vascular hyperintensities (FVH)–DWI mismatch could identify candidates for thrombectomy most likely to benefit from revascularization.
Methods
We retrospectively ...reviewed 100 patients with proximal MCA occlusion from 18 stroke centers randomized in the IV-thrombolysis plus mechanical thrombectomy arm of the THRACE trial (2010–2015). We tested the associations between successful revascularization on digital subtraction angiography (modified Thrombolysis in Cerebral Infarction 2b/3) and 3-month favorable outcome (modified Rankin Scale score ≤ 2), stratified on FVH–DWI mismatch status, with secondary analyses adjusted on National Institutes of Health Stroke Scale (NIHSS) and DWI lesion volume.
Results
FVH–DWI mismatch was present in 79% of patients, with a similar prevalence at 1.5 T (80%) and 3 T (78%). Successful revascularization (74%) was more frequent in patients with FVH–DWI mismatch (63/79, 80%) than in patients without (11/21, 52%),
p
= 0.01. The OR of favorable outcome for revascularization were 15.05 (95% CI 3.12–72.61,
p
< 0.001) in patients with FVH–DWI mismatch and 0.83 (95% CI 0.15–4.64,
p
= 0.84) in patients without FVH–DWI mismatch (
p
= 0.011 for interaction). Similar results were observed after adjustment for NIHSS (OR = 12.73 95% CI 2.69–60.41,
p
= 0.001 and 0.96 95% CI 0.15–6.30,
p
= 0.96) or for DWI volume (OR = 12.37 95% CI 2.76–55.44,
p
= 0.001 and 0.91 95% CI 0.16–5.33,
p
= 0.92) in patients with and without FVH–DWI mismatch, respectively.
Conclusions
The FVH–DWI mismatch identifies patients likeliest to benefit from revascularization, irrespective of initial DWI lesion volume and clinical stroke severity, and could serve as a useful surrogate marker for penumbral evaluation.
Key Points
•
The FVH–DWI mismatch, defined by FLAIR vascular hyperintensities (FVH) located beyond the boundaries of the DWI lesion, is associated with large penumbra.
•
Among stroke patients with proximal middle cerebral artery occlusion referred for thrombectomy, those with FVH–DWI mismatch are most likely to benefit from revascularization.
•
FVH–DWI mismatch provides an alternative to PWI–DWI mismatch in order to select patients who are candidates for thrombectomy.
•ASL is useful to detect and characterize acute seizure.•In acute deficit, ASL can comfort seizure diagnosis and rule out stroke.•ASL abnormalities are well correlated with EEG findings.•ASL is more ...sensitive than conventional MR sequences of seizure identification.•Compared with other pathological causes of hyperperfusion, such as migraine or luxury perfusion in stroke, ASL exhibits some specific aspects especially remote pulvinar and contralateral cerebellar activation.
Arterial spin labeling (ASL) is a non-invasive tool measuring cerebral blood flow (CBF) and is useful to assess acute neurological deficit. While acute stroke presents as hypoperfused vascular territory, epileptic activity causes cortical hyperperfusion. Other neurological conditions exhibit hyperperfusion, like migraine or secondary “luxury perfusion” in strokes. Our objectives were to evaluate the usefulness and potential specificities of ASL in acute seizure and correlate it with electroencephalogram.
Amongst a cohort of patients with neurological deficit, addressed for suspicion of stroke, we retrospectively reviewed 25 consecutive patients with seizures who underwent magnetic resonance imaging (MRI) with ASL and electroencephalography (EEG). We compared them with a control group of patients with migraine and stroke secondary re-perfusion, exhibiting ASL hyperperfusion.
Lateralized cortical hyperperfusion (high relative CBF) was observed in all patients. Good topographic correlation with EEG was found in 18 patients (72%). Eight (32%) had hyperperfusion of ipsilateral pulvinar, 5 (20%) had hyperperfused contralateral cerebellar hemisphere, 16 (64%) presented diffusion abnormalities and 20 (80%) had underlying epileptogenic lesions. Pulvinar hyperperfusion was not observed in the control group, nor were diffusion abnormalities in migrainous patients. Contralateral cerebellar hyperperfusion was observed in two migrainous patient, without associated pulvinar activation, whereas all patients with cerebellar hyperperfusion in the study group had associated pulvinar activation.
Elevated CBF can be observed in the epileptogenic zone, ipsilateral pulvinar and contralateral cerebellum (diaschisis) in seizure. These abnormalities seem specific when compared with other causes of hyperperfusion. Arterial spin labeling can be highly effective in the differential diagnosis of strokes.
The 2021 WHO classification of CNS tumors has refined the definition of adult-type diffuse gliomas without 1p19q codeletion. Nevertheless, the aggressiveness of gliomas is based exclusively on ...histomolecular criteria performed on a limited sample of the tumor. The authors aimed to assess whether the spontaneous radiographic tumor growth rate is associated with tumor aggressiveness and allows preoperative identification of malignancy grade of adult-type diffuse gliomas without 1p19q codeletion.
The authors retrospectively reviewed the records of adult patients harboring a newly diagnosed supratentorial diffuse glioma without 1p19q codeletion, with available preoperative MRI follow-up between January 2008 and April 2022. The spontaneous radiographic tumor growth rate was quantified by tumor volume segmentation and regression of the evolution of the mean tumor diameter over time and was compared with clinical, imaging, histomolecular, and survival data.
Ninety-six patients were included. The spontaneous radiographic tumor growth rates (mean 17.8 ± 38.8 mm/year, range 0-243.5 mm/year) significantly varied according to IDH1/2 mutation (p < 0.001), grade of malignancy (p < 0.001), and presence of microvascular proliferation (p < 0.001). The spontaneous radiographic tumor growth rate allowed preoperative identification of high-grade cases: 100% of grade 3 and 4 IDH-mutant diffuse astrocytomas had a spontaneous radiographic tumor growth rate ≥ 8.0 mm/year, and 100% of IDH-wild-type glioblastomas had a spontaneous radiographic tumor growth rate ≥ 42.0 mm/year. A spontaneous radiographic growth rate ≥ 8.0 mm/year was an independent predictor of shorter progression-free (p = 0.014) and overall (p = 0.007) survival. A mitotic count threshold ≥ 4 mitoses was the optimal threshold for identifying aggressive IDH-mutant astrocytomas based on spontaneous radiographic tumor growth.
The spontaneous radiographic tumor growth rates could be used as an additional tool to preoperatively screen tumor aggressiveness of adult-type diffuse gliomas without 1p19q codeletion.
The use of relaxometry and Diffusion-Tensor Imaging sequences for brain tumor assessment is limited by their long acquisition time. We aim to test the effect of a denoising algorithm based on a Deep ...Learning Reconstruction (DLR) technique on quantitative MRI parameters while reducing scan time. In 22 consecutive patients with brain tumors, DLR applied to fast and noisy MR sequences preserves the mean values of quantitative parameters (fractional anisotropy, mean diffusivity, T1 and T2-relaxation time) and produces maps with higher structural similarity compared to long duration sequences. This could promote wider use of these biomarkers in clinical setting.
Background & Aims
Post‐procedural pain is frequent after transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC), and is only partially prevented by treatment selectivity. Our aim ...was to determine the risk factors of severe pain after selective TACE for HCC.
Methods
From January 2012 to June 2014, all treatment‐naïve patients undergoing a first selective TACE were included. Risk factors for severe pain, that is, the need for opioid analgesics (grade II–III), were identified by uni‐ and multivariate analysis. Internal validation of a logistic regression model for prediction of opioid intake was done with bootstrapping.
Results
We analysed 335 tumours (mean 47 ± 37 mm) in 159 patients (131 men), mean 63.4 years old (20–92). Twenty‐seven patients (17%) requested opioids. In univariate analysis, opioid intake was associated with young age (P=.021), doxorubicin dose received (P=.031), large HCC (P=.038), absence of chronic liver disease (P<.001) and alpha‐foetoprotein levels (P=.03). In multivariate analysis, opioid intake was associated with young age (OR=0.65 per 10 years increment, P=.048), absence of chronic liver disease (OR=31.7, P<.001) and a higher fraction of the doxorubicin dose (OR=1.32 per 10% increment, P=.009). The optimism‐corrected area under the curve of the prediction model for opioid intake using these three factors was 0.751.
Conclusion
In patients with HCC treated with TACE, selective procedure does not always prevent from severe pain. Young patients without chronic liver disease may be more susceptible to severe pain.
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