T2-highlighted U-fibres and rapid parenchymal volume loss in AESD: an under-recognised subtype of paediatric acute encephalopathy syndromes Publication date: Available online 4 October 2019 Source: Journal of Neuroradiology Author(s): Saipriya Ramji, Gary McCullagh, Dipak Ram, Grace Vassallo, Julija Pavaine Abstract Acute Encephalopathy with Reduced Subcortical Diffusion or AED is a unique subtype of acute paediatric encephalopathy which presents with altered mental status, prolonged seizures and developing characteristic radiological signal changes within the subcortical white matter. Reports of such cases have mainly been from Japan[1] and this radiological finding has been recognised as a novel feature of AED. We present three paediatric cases from a tertiary paediatric neurosciences centre in xxxxx with characteristic subcortical signal change, and furthermore, follow up imaging which in all 3 patients demonstrated a varying degree of cerebral atrophy. We recommend that children presenting with prolonged seizures should be considered for MR imaging ideally after 48 hours if clinically stable, and early MR imaging follow-up (at 2-3 months) be performed routinely in patients with AED to assess for presence and degree of parenchymal volume loss for prognostication and to start neuroprotective therapy.

Agreement of intracranial vessel diameters measured on 2D and 3D digital subtraction angiography using an automatic windowing algorithm Publication date: Available online 26 September 2019 Source: Journal of Neuroradiology Author(s): Yukiko Abe, Ichiro Yuki, Katharina Otani, Tomokazu Shoji, Toshihiro Ishibashi, Yuichi Murayama ABSTRACT Background and purpose: Precise vessel measurement plays a major role in size selection of stents used for the treatment of intracranial aneurysms and became even more critical after the introduction of flow diverter stents. We assessed agreement between intracranial vessel diameters of aneurysm patients measured on 2D digital subtraction (2D DSA) and 3D volume rendering digital subtraction angiography (3D DSA) images using an automatic windowing algorithm. Materials and Methods: Ten patients with intracranial aneurysms were enrolled and 120 measurement points were selected on both 2D and 3D DSA images acquired by a biplane angiographic system. Automatic windowing was applied to the 3D DSA images. Inter-method agreement of vessel measurements on 2D and 3D DSA images was assessed by Bland Altman plots and intraclass correlation coefficients (ICC). Inter- and intra-rater agreement of measurements on 3D DSA images were assessed by ICCs. Results: The mean differences between measurements on 2D and 3D DSA images were 0.14 mm for the ICA, and 0.18 mm for the ACA and MCA, which is about the size of one 3D DSA image voxel. For ICA measurements, inter-method, inter-rater and intra-rater agreements were good or excellent (consistency and absolute ICC≥0.95). For ACA and MCA measurements, the inter-method, inter-rater and intra-rater agreements were also good or excellent (consistency ICC = 0.94, 0.89 and 0.93, absolute ICC = 0.83, 0.84 and 0.85 respectively). Conclusions: Vessel diameters may be measured on 3D DSA images with sufficient reliability for clinical use when applying an automatic windowing algorithm.

A randomized pilot study of patients with tandem carotid lesions undergoing thrombectomy Publication date: Available online 26 September 2019 Source: Journal of Neuroradiology Author(s): Alexandre Y. Poppe, Grégory Jacquin, Christian Stapf, Nicole Daneault, Yan Deschaintre, Laura C. Gioia, Céline Odier, Marilyn Labrie, Ahmad Nehme, Lorena Nico, Daniel Roy, Alain Weill, Jean Raymond Abstract Background and purpose The optimal management of patients with tandem lesions (TL), or cervical internal carotid artery (c-ICA) steno-occlusive pathology and ipsilateral intracranial occlusion, who are undergoing endovascular thrombectomy (EVT) remains unknown. We sought to establish the feasibility of a trial designed to address this question. Materials and methods The Endovascular Acute Stroke Intervention (EASI) study was a single-centre randomized trial comparing EVT to medical therapy for large-vessel occlusion stroke. Patients with TL receiving EVT were randomly allocated to acute c-ICA stenting or no stenting. The primary outcome was the proportion of patients with a modified Rankin Scale (mRS) score of 0–2 at 90 days. Safety outcomes were symptomatic intracranial hemorrhage (sICH) at 24 hours and mortality at 90 days. Results Of 301 patients included in EASI between 2013 and 2018, 24 (8.0%) with TL were randomly allocated to acute stenting (n = 13) or no stenting (n = 11). Baseline characteristics were balanced. Eight (61.5%; 95% CI 35.5%–82.3%) and 7 (63.6%; 95% CI 35.4%–84.9%) patients, respectively, had a favorable outcome (mRS 0–2; P = 1.0). One non-stented patient had a symptomatic intracerebral hemorrhage. Conclusions This pilot trial of patients with TL undergoing EVT suggests that a sufficiently powered larger TL trial comparing acute c-ICA stenting to no stenting is feasible. Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT02157532. Graphical abstract

Intraoperative MRI and FLAIR Analysis: Implications for low-grade glioma surgery Publication date: Available online 26 September 2019 Source: Journal of Neuroradiology Author(s): Myriam Edjlali, Loïc Ploton, Claude-Alain Maurage, Christine Delmaire, Jean-Pierre Pruvo, Nicolas Reyns, Xavier Leclerc Abstract Purpose Intraoperative MRI (iMRI) offers the possibility of acquiring intraoperatively real-time images that will guide neurosurgeons when removing brain tumors. The objective of this study was to report the existence of FLAIR abnormalities on iMRI that may occur on the margin of a brain resection and may lead to misdiagnosis of residual tumor. Methods We retrospectively analyzed intraoperative MRI (iMRI) in 21 consecutive patients who underwent surgery for a low-grade glioma. Two readers independently reviewed iMRI images to search for the presence of a FLAIR hyperintensity surrounding the surgical cavity. For each patient, they were instructed to characterize FLAIR abnormalities on the margins of the resected area as (1) no FLAIR abnormality; (2) “linear FLAIR hyperintensity (LFH)”, when a < 5 mm linear FLAIR hyperintensity was present; or (3) “nodular FLAIR hyperintensity (NFH)”, in the case of a thick and nodular FLAIR hyperintensity. Results LFH were present on at least one surgical margin of one third of the patients analyzed with iMRI, and vanished on follow-up MRI, confirming its transient condition; whereas NFH were linked to persistence of pre-surgical abnormalities, such as residual tumor as confirmed or by histopathological analysis of a second surgery or by its remnant on follow-up MRI. Conclusion Linear FLAIR hyperintensities can be present on surgical margins analyzed by iMRI and should not be mistaken for residual tumor.

Simmons Angled microguidewire INsertion to the Target (SAINT) technique in neuroendovascular therapy Publication date: Available online 26 September 2019 Source: Journal of Neuroradiology Author(s): Bikei Ryu, Shinsuke Sato, Tatsuya Inoue, Yoshikazu Okada, Yasunari Niimi Abstract Advancing appropriate microcatheters is essential for treatment. However, we still encounter inaccessible arterial branches because of the anatomical arrangement. While many successful techniques regarding microcatheters have been reported, there have been very few reports of microguidewire-shaping techniques. We developed the Simmons-Angled microguidewire INsertion to the Target (SAINT) technique for insertion of the microguidewire into inaccessible arterial branches. The SAINT technique is feasible for selection and insertion into arteries that are inaccessible with conventional methods.

Posterior fossa tumors in children: Radiological tips & tricks in the age of genomic tumor classification and advance MR technology Publication date: Available online 18 September 2019 Source: Journal of Neuroradiology Author(s): Basile Kerleroux, Jean Philippe Cottier, Kévin Janot, Antoine Listrat, Dominique Sirinelli, Baptiste Morel Abstract Imaging plays a major role in the comprehensive assessment of posterior fossa tumor in children (PFTC). The objective is to propose a global method relying on the combined analysis of radiological, clinical and epidemiological criteria, (taking into account the child's age and the topography of the lesion) in order to improve our histological approach in imaging, helping the management and approach for surgeons in providing information to the patients’ parents. Infratentorial tumors are the most frequent in children, representing mainly medulloblastoma, pilocytic astrocytoma and brainstem glioma. Pre-surgical identification of the tumor type and its aggressiveness could be improved by the combined analysis of key imaging features with epidemiologic data.

Patient and aneurysm factors associated with aneurysm rupture in the population of the ARETA study Publication date: Available online 17 September 2019 Source: Journal of Neuroradiology Author(s): Laurent Pierot, Coralie Barbe, Jean-Christophe Ferré, Christophe Cognard, Sébastien Soize, Phil White, Laurent Spelle Abstract Background and purpose Identifying patients with intracranial aneurysms (IA) who have a high risk of rupture is critical to determine optimal management. ARETA (Analysis of Recanalization after Endovascular Treatment of intracranial Aneurysm) is a prospective, multicenter study, dedicated to evaluating endovascular treatment of IA. We aimed to identify factors associated with ruptured status, using this very large series of patients with ruptured and unruptured aneurysms. Methods Several analyses were conducted in the ARETA population: univariate and multivariate analyses in the whole population of patients and aneurysms to determine patient and aneurysm factors associated with aneurysm rupture, as well as a matched pair analysis (based on aneurysm size) conducted in the subgroup of patients with only one aneurysm to analyze the patient and aneurysm factors simultaneously. Results From December 2013 to May 2015, 1289 patients with 1761 aneurysms were included in ARETA. The multivariate analysis identified four patient factors: elevated blood pressure (EBP), no familial history, single IA, and active smoking, and four aneurysm factors: size ≥ 5 mm, narrow neck, irregular shape, and ACA/Acom location, associated with rupture status. In the matched pair analysis, five risk factors of rupture were identified: no familial history of aneurysm, narrow neck, active smoking, ACA/Acom location, and irregular shape. Conclusions The most important patient factors associated with IA rupture are smoking and EBP. Given that size is a well-identified aneurysm factor, narrow neck also seems to be associated with aneurysm rupture. Further studies are needed to confirm this factor and determine underlying mechanisms. Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01942512.

Central Nervous System involvement in tuberculosis: An MRI study considering differences between patients with and without Human Immunodeficiency Virus 1 infection Publication date: Available online 17 September 2019 Source: Journal of Neuroradiology Author(s): Alberto Di Napoli, Massimo Cristofaro, Andrea Romano, Elisa Pianura, Gioia Papale, Federica Di Stefano, Edoardo Ronconi, Ada Petrone, Maria Camilla Rossi Espagnet, Vincenzo Schininà, Alessandro Bozzao Abstract Background Magnetic resonance imaging (MRI) is largely used in the diagnosis of central nervous system involvement of tuberculosis (CNSTB), yet there is no MRI comparison study between HIV+ and HIV− patients with CNSTB. The aim of the present study was to identify MRI differences in CNSTB between HIV+ and HIV− patients and possibly find early characteristics that could raise the suspect of this disease. Methods We included all patients admitted in our institution between 2011 and 2018 with confirmed diagnosis of CNSTB, and MRI performed in the first week. Patients with preexisting brain pathology or immunodeficiency not HIV related were excluded. We compared CNSTB MRI features between the two groups. Results Sixty-nine patients were included (19 HIV+; 50 HIV−). Findings in HIV+ group: 6 lung TB, 5 hydrocephalus, 4 meningeal enhancement, 6 stroke, 2 hemorrhages, and 10 tuberculomas. HIV− group: 22 lung tuberculosis, 15 hydrocephalus, 21 meningeal enhancement, 5 stroke, 4 hemorrhages, 20 tuberculomas. The only statistically significant difference between the two groups was in the stroke occurrence, more frequent in the HIV+ group (P = .028), all involving the basal ganglia. Conclusions Stroke involving the basal ganglia best differentiates CNSTB patients who are HIV+ from those HIV−. This finding was not correlated with meningeal enhancement suggesting that small arteries involvement might precede it. Therefore, we think that HIV+ patients with a new onset of stroke should be evaluated for CNSTB. Follow-up MRI should also be planned since meningeal enhancement might appear in later stages of the disease. Graphical abstract

Limited positive predictive value of diffusion tensor tractography in determining clinically relevant white matter damage in brain stem cavernous malformations: A retrospective study in a single center surgical cohort Publication date: Available online 17 September 2019 Source: Journal of Neuroradiology Author(s): Osman Melih Topcuoglu, Cunhur Kaan Yaltirik, Zeynep Firat, Ayşegul Sarsilmaz, Mehmet Volkan Harput, Basar Sarikaya, Uğur Ture Abstract Purpose Diffusion tensor tractography (DTT) might reflect the postoperative clinical outcome of the patients with brain stem (BS) tumors correlating well with the neurological symptoms, but cavernous malformation (CM) is a hemorrhagic tumor prone to artifacts that may limit DTT. We set out to determine the correlation of DTT findings with the neurological examination before and after surgical resection in patients with BSCMs. Materials and methods DTT findings were evaluated bilaterally for fiber tract displacement or deviation, deformation and interruption in every patient before and after the surgery. Neurological examination was performed at admission, discharge and outpatient follow-up visit. The sensitivity, specificity, positive and negative predictive values of DTT were calculated both pre- and post-operatively. Results There were 25 patients (9 men 16 women) with a mean age of 39.5 ± 13.9 years. The mean size of the CMs was 6909 ± 8374 mm3 (range: 180–38,220 mm3) The mean follow-up time was 42.7 ± 23.2 months (range: 8 to 112 months). Preoperatively, the sensitivity, specificity, positive and negative predictive values of DTT for corticospinal tracts (CST) and medial lemnisci (ML) were 100%, 60%, 38.4%, 100% and 87.5%, 11.7%, 31.8%, 66.6%, respectively. Postoperatively, the sensitivity, specificity, positive and negative predictive values of DTT for CSTs and ML were 100%, 64.7%, 40%, 100% and 100%, 0%, 33.3%, 66.6%, respectively. Conclusion Positive findings on DTT such as fiber tract deviation, deformation, disruption or interruption should be taken cautiously before drawing conclusions of a clinically relevant damage of white matter tracts.

Safety and effectiveness of CATCH+ as a first-line device for revascularization in the treatment of acute ischemic stroke Publication date: Available online 17 September 2019 Source: Journal of Neuroradiology Author(s): Elena Ernst, Panagiotis Papanagiotou, Mary Politi, Maria Alexandrou, Andreas Kastrup, Maria Boutchakova, Christian Roth Abstract Purpose Mechanical thrombectomy devices and stent retrievers have recently been advocated for use as first-line therapy in acute ischemic stroke. Here we evaluate the safety and effectiveness of the CATCH+ stent retriever as a percutaneous thrombectomy device. Methods A retrospective analysis was performed on 101 consecutive patients who presented with anterior or posterior intracranial vessel occlusion and were treated with the CATCH+ intracranial system, either alone or in combination with intravenous tissue plasminogen activator, at a single treatment center. The primary outcome measure was successful post-procedural reperfusion as classified by the mTICI score. Secondary endpoints included mortality rate, incidence of adverse events, and functional outcomes evaluated at discharge using the mRS score. Results Sixty-nine (68.3%) patients received thrombolysis prior to mechanical thrombectomy. Successful reperfusion (mTICI ≥ 2b) was achieved in 73.3% of patients at the end of the procedure, and good functional outcomes (mRS ≤ 2) were observed in 32.7% of patients at discharge. Three patients developed asymptomatic subarachnoid hemorrhage, two developed asymptomatic dissections of the internal carotid artery, and one patient developed a symptomatic intracranial hemorrhage. Seventeen patients died (mortality rate 16.8%). Conclusions The CATCH+ device is a safe and effective mechanical thrombectomy device for the first-line treatment of acute ischemic stroke.