Stroke due to Percheron Artery Occlusion: Description of a Consecutive Case Series from Southern Portugal

The artery of Percheron (AOP) is an abnormal variant of the arterial supply of the thalamus. Stroke caused by AOP occlusion is seldom reported. AOP leads to bilateral thalamic and rostral midbrain infarct presenting with unspecific manifestations. There are few descriptions of case series of stroke caused by AOP. We sought to review the clinicoradiological characteristics of AOP infarction from Algarve, Southern Portugal. Eight consecutive cases were retrospectively identified by searching the electronic clinical charts, as well as the stroke Unit database (2015–2020). Sociodemographic (age and gender) and clinicoradiological characteristics (etiological classification, admission severity, manifestations, and short- and long-term prognoses) were retrieved. The corresponding frequency of AOP infarction was 0.17% (95% confidence interval: 0.05–0.28). The mean age was 67.1 (range: 60–80) years. The range of stroke severity evaluated assessed by the National Institute of Health Stroke Scale ranged from 5 to 23 (median = 7.5). None of the patients receive acute ischemic stroke reperfusion treatment. AOP patterns were isolated bilateral paramedian thalamic (n = 2), bilateral paramedian and anterior thalamic (n = 2), and bilateral paramedian thalamic with rostral midbrain (n = 4). Two patients (20%) died on the short term (30 days). At hospital discharge, six patients had functional disability of ≤2 on the modified Rankin scale. In the follow-up at 6 months, half (n = 3) of the survivors had persistent hypersomnia and two had vascular dementia. Stroke from AOP presents with variable clinical and radiological presentations and patients do not receive alteplase. The short-term survivor and the long-term functional independency can be compromised after AOS infarct.

Endovascular Treatment of Medial Tentorial Dural Arteriovenous Fistula Through the Dural Branch of the Pial Artery

Background: Tentorial dural arteriovenous fistula is a rare subtype of intracranial dural arteriovenous fistula (DAVF) with a deteriorating natural course, which may be attributed to its pial angioarchitecture. TDAVF often harbors feeders arising from pial arteries (FPAs). Reports have revealed that, if these feeders are not obliterated early, the restricted venous outflow during the embolization process may cause upstream congestion in the fragile pial network, which increases the risk of hemorrhagic complications. Because most reported cases of TDAVF were embolized through feeders from non-pial arteries (FNPAs), little is known of the feasibility of direct embolization through FPAs.Methods: We present three patients with medial TDAVFs that were embolized through the dural branches of the posterior cerebral and superior cerebellar arteries. Findings from brain magnetic resonance imaging, computed tomography, angiography, and clinical outcomes are described. Furthermore, we performed a review of the literature on TDAVFs with FPAs.Results: The fistulas were completely obliterated in two patients; both recovered well with no procedure-related complications. The fistula was nearly obliterated in one patient, who developed left superior cerebellum and midbrain infarct due to the reflux of the embolizer into the left superior cerebellar artery. Including our cases, eight cases of TDAVFs with direct embolization through the FPAs have been reported, and ischemic complications occurred in three (37.5%).Conclusions: Advancing microcatheter tips as close to the fistula point as possible and remaining highly aware of potential embolizer flow back into the pial artery are key factors in achieving successful embolization. Balloon-assisted embolization may be an option for treating TDAVFs with FPAs in the future.

Prognostic Structural Neural Markers of MRI in Response to Mechanical Thrombectomy for Basilar Artery Occlusion

Objective: Mechanical thrombectomy (MT) has been an effective first-line therapeutic strategy for ischemic stroke. With impairment characteristics separating it from anterior circulation stroke, we aimed to explore prognostic structural neural markers for basilar artery occlusion (BAO) after MT.Methods: Fifty-four BAO patients with multi-modal magnetic resonance imaging at admission from the multicenter real-world designed BASILAR research were enrolled in this study. Features including volumes for cortical structures and subcortical regions, locations and volumes of infarctions, and white matter hyperintensity (WMH) volumes were recorded from all individuals. The impact features were identified using ANCOVA and logistic analysis. Another cohort (n = 21) was further recruited to verify the prognostic roles of screened prognostic structures.Results: For the primary clinical outcome, decreased brainstem volume and total infarction volumes from mesencephalon and midbrain were significantly related to reduced 90-day modified Rankin score (mRS) after MT treatment. WMH volume, WMH grade, average cortex thickness, white matter volume, and gray matter volume did not exhibit a remarkable relationship with the prognosis of BAO. The increased left caudate volume was obviously associated with early symptomatic recovery after MT. The prognostic role of the ratio of pons and midbrain infarct volume in brainstem was further confirmed in another cohort with area under the curve (AUC) = 0.77.Conclusions: This study was the first to provide comprehensive structural markers for the prognostic evaluation of BAO. The fully automatic and semiautomatic segmentation approaches in our study supported that the proportion of mesencephalon and midbrain infarct volume in brainstem was a crucial prognostic structural neural marker for BAO.

Bilateral, vertical supranuclear gaze palsy following unilateral midbrain infarct

A 60-year-old man recently admitted for bipedal oedema, endocarditis and a persistently positive COVID-19 swab with a history of anticoagulation on rivaroxaban for atrial fibrillation, transitional cell carcinoma, cerebral amyloid angiopathy, diabetes and hypertension presented with sudden onset diplopia and vertical gaze palsy. Vestibulo-ocular reflex was preserved. Simultaneously, he developed a scotoma and sudden visual loss, and was found to have a right branch retinal artery occlusion. MRI head demonstrated a unilateral midbrain infarct. This case demonstrates a rare unilateral cause of bilateral supranuclear palsy which spares the posterior commisure. The case also raises a question about the contribution of COVID-19 to the procoagulant status of the patient which already includes atrial fibrillation and endocarditis, and presents a complex treatment dilemma regarding anticoagulation.

Artery of percheron infarction: case reports and literature review

The artery of Percheron is a rare anatomic variant supplying the thalamus and the rostral midbrain. Infarct in this territory results in a wide array of neurological signs and symptoms causing diagnostic dilemma and management issues. We describe the clinical presentations in three cases admitted and evaluated for neurological symptoms and diagnosed as artery of percheron infarct after brain imaging. In one patient, the etiology turned out to be infective while the other two patients had cerebrovascular accident secondary to dilated cardiomyopathy and hyper homcystinimea respectively. Artery of percheron infarction is a rare entity and should be considered in patients with altered sensorium and behavioral manifestations with associated eye abnormalities. MRI brain is the investigation of choice to detect this rare variant of thalamic circulation.

Focal123I-FP-CIT SPECT Abnormality in Midbrain Vascular Parkinsonism

Cerebrovascular diseases are considered among possible causes of acute/subacute parkinsonism, representing up to 22% of secondary movement disorders. In cases of suspected vascular parkinsonism (VP), dopamine transporter SPECT has been highly recommended to exclude nigrostriatal dopaminergic degeneration. We report the case of a hemiparkinsonism related to a left midbrain infarct with focal lateralized putaminal abnormalities at123I-FP-CIT SPECT imaging. The asymmetric uptake at dopamine transporter SPECT was different to findings commonly observed in typical PD pattern, because the ipsilateral striatum, in opposite to idiopathic PD, showed normal tracer binding. However, this selective parkinsonism after infarction of the midbrain was responsive to levodopa. In conclusion, we retain that there is a need of more functional imaging studies in VP addressed to a more consistent classification of its different clinical forms and to a better understanding of the adequate pharmacological management.