Mechanical thrombectomy in acute basilar artery stroke: a systematic review and Meta-analysis of randomized controlled trials.

BACKGROUND: The evidence for mechanical thrombectomy in acute basilar artery occlusion has until now remained inconclusive with basilar artery strokes associated with high rates of death and disability. This systematic review and meta-analysis will summarize the available evidence for the effectiveness of mechanical thrombectomy in acute basilar artery occlusion compared to best medical therapy. METHODS: We conducted a systematic review and meta-analysis of randomized controlled trials using Embase, Medline and the Cochrane Central Register of Controlled Trials (CENTRAL). We calculated risk ratios (RRs) and 95% confidence intervals (CIs) to summarize the effect estimates for each outcome. RESULTS: We performed a random effects (Mantel-Haenszel) meta-analysis of the four included randomized controlled trials comprising a total of 988 participants. We found a statistically significant improvement in the rates of those with a good functional outcome (mRS 0-3, RR 1.54, 1.16-2.06, p = 0.003) and functional independence (mRS 0-2, RR 1.69, 1.05-2.71, p = 0.03) in those who were treated with thrombectomy when compared to best medical therapy alone. Thrombectomy was associated with a higher level of sICH (RR 7.12, 2.16-23.54, p = 0.001) but this was not reflected in a higher mortality rate, conversely the mortality rate was significantly lower in the intervention group (RR 0.76, 0.65-0.89, p = 0.0004). CONCLUSIONS: Our meta-analysis of the recently presented randomized controlled studies is the first to confirm the disability and mortality benefit of mechanical thrombectomy in basilar artery stroke.

Axonal marker neurofilament light predicts long-term outcomes and progressive neurodegeneration after traumatic brain injury.

Axonal injury is a key determinant of long-term outcomes after traumatic brain injury (TBI) but has been difficult to measure clinically. Fluid biomarker assays can now sensitively quantify neuronal proteins in blood. Axonal components such as neurofilament light (NfL) potentially provide a diagnostic measure of injury. In the multicenter BIO-AX-TBI study of moderate-severe TBI, we investigated relationships between fluid biomarkers, advanced neuroimaging, and clinical outcomes. Cerebral microdialysis was used to assess biomarker concentrations in brain extracellular fluid aligned with plasma measurement. An experimental injury model was used to validate biomarkers against histopathology. Plasma NfL increased after TBI, peaking at 10 days to 6 weeks but remaining abnormal at 1 year. Concentrations were around 10 times higher early after TBI than in controls (patients with extracranial injuries). NfL concentrations correlated with diffusion MRI measures of axonal injury and predicted white matter neurodegeneration. Plasma TAU predicted early gray matter atrophy. NfL was the strongest predictor of functional outcomes at 1 year. Cerebral microdialysis showed that NfL concentrations in plasma and brain extracellular fluid were highly correlated. An experimental injury model confirmed a dose-response relationship of histopathologically defined axonal injury to plasma NfL. In conclusion, plasma NfL provides a sensitive and clinically meaningful measure of axonal injury produced by TBI. This reflects the extent of underlying damage, validated using advanced MRI, cerebral microdialysis, and an experimental model. The results support the incorporation of NfL sampling subacutely after injury into clinical practice to assist with the diagnosis of axonal injury and to improve prognostication.

Patients with in-situ metallic coils and Amplatzer vascular plugs used to treat pulmonary arteriovenous malformations since 1984 can safely undergo magnetic resonance imaging.

OBJECTIVE: To examine the MRI safety of metallic coils and Amplatzer vascular plugs. Currently, concern regarding MR safety of devices used to treat pulmonary arteriovenous malformations (PAVMs) causes delays in performing emergency MRI in patients presenting with acute neurological symptoms. METHODS: A retrospective audit was performed on all patients who underwent PAVM embolization at Hammersmith Hospital, London UK between 1984 and 2017. Outcomes of all MRI studies performed at our institution were recorded. In addition, known outcomes of all known MRI studies performed on patients treated with the earliest steel coils (1984-1995) were recorded. RESULTS: At our institution, 20 patients underwent 1.5 T MRI after the insertion of 100 steel coils (15.5 - 28.6, median 22 years later), 140 coils designated MR-conditional (0.42 - 12.7, median 9.3 years later), and 54 MRI-conditional Amplatzer vascular plugs (0.17 - 8.0, median 0.75 years later), many in combination. The majority of scans were for cerebral indications, but other body regions scanned included spinal, thoracic, and pelvic regions. No adverse events were reported. Similarly, there were no adverse events in any MR scan known to have been performed in other institutions in seven further patients treated with the earliest steel coils (1984-1995). Again, the majority of scans were for cerebral indications. CONCLUSION: The findings demonstrate MR safety at 1.5 T of all PAVM embolization devices inserted in a main UK centre since inception in 1984. ADVANCES IN KNOWLEDGE: MRI of patients who have had PAVMs treated by embolization can be implemented without contacting specialist pulmonary arteriovenous malformation treatment centres for approval.

Uptake and radiological findings of screening cerebral magnetic resonance scans in patients with hereditary haemorrhagic telangiectasia.

Hereditary haemorrhagic telangiectasia (HHT) results in arteriovenous malformations (AVMs), most commonly in the lungs, liver and brain. Discussion of cerebral vascular malformations is an important element of patient management. The current study objectives were to examine uptake and results of screening cerebral magnetic resonance (MR) scans, excluding symptomatic patients requiring neurological investigations. The remaining non-symptomatic individuals received formal pretest counselling that differed according to family history. For the 603 patients with no neurological symptoms of concern, screening scan uptake was higher after publication of the ARUBA trial. Patients with a family history of cerebral haemorrhage were 4 to 14-fold more likely to have a screening scan than patients with no such family history. For patients without neurological symptoms suggesting cerebral AVMs, none of the 59 screening scans performed at our institution demonstrated a cerebral AVM. Four scans (6.8%) demonstrated small aneurysms. The most common abnormality was cerebral infarction (20/59, 33.9%), predominantly identified in patients with pulmonary AVMs. Of 29 pulmonary AVM patients with no previous history of clinical stroke, 16 (55.2%) had between one and five silent infarcts. For HHT patients with pulmonary AVMs, the most frequently affected sites were the cerebellum (40%) and thalamus (14.3%), and the age-adjusted odds ratio for an infarct was 21.6 (95% confidence intervals 3.7, 126), p = 0.001. We concluded that for cerebral screening programmes in HHT, the findings support informed patient choice incorporating understanding that cerebral AVMs are rare in non-symptomatic HHT patients, but that screening scans commonly detect silent cerebral infarction due to pulmonary AVMs.