Ratika Srivastava MD FRCPC1, Stephanie Hammond MD2, Michael J Esser MD PhD FRCPC2, Adam Kirton MD MSc FRCPC2, & Aleksandra Mineyko MD FRCPC2
- Division of Pediatric Neurology, Department of Pediatrics, University of Alberta. AB, Canada
- Department of Pediatrics and Clinical Neurosciences, University of Calgary, Calgary AB Canada
Perinatal stroke is a focal vascular brain injury that occurs from the fetal period to 28 days of postnatal life1,2. The most focused lifetime risk for stroke occurs in the perinatal period3 with an overall incidence of up to 1 in 1,000 live births4. Neonatal arterial ischemic stroke (NAIS), an ischemic stroke involving arterial territories that presents in the term neonate, is the most common type of perinatal stroke and most often affects the anterior circulation1. Posterior circulation strokes are uncommon in neonates and presumed to occur in less than 20% of all NAIS cases4,5 (Table 1). Although thromboembolic occlusion is a presumed mechanism, thrombus detection at diagnosis is uncommon and evidence of residual thrombus in the basilar artery extremely rare.
We describe the case of a term neonate who presented with acute symptomatic seizures and was found to have basilar artery thrombosis with multifocal ischemic strokes in the posterior circulation, leading to complex management considerations.
Baby M was born to a healthy 25-year-old mother with no complications or exposures during pregnancy. He was delivered at 38+5 weeks gestation via vacuum-assisted vaginal delivery after prolonged fetal heart rate decelerations. Birth weight was 2520 g. APGARS were 4,7,8 at 1 minute, 5 minutes, and 10 minutes respectively. Initial resuscitation measures included positive pressure ventilation (PPV) and continuous positive airway pressure (CPAP), with transition to room air by four minutes of life. At 3 hours of life, he had recurrent apneas associated with eye fluttering, right arm posturing, and right leg cycling which responded clinically to phenobarbital 20 mg/kg. On initial examination he was encephalopathic requiring ventilatory support and significantly hypotonic with minimal spontaneous movement. Reflexes were symmetric. He had a large cephalohematoma and was thrombocytopenic with platelets of 49 x10E9/L. Blood glucose was 1.1 mmol/L, requiring ongoing infusions of 20% dextrose for glycemic control. Dopamine was required for persistent hypotension. Workup for adrenal insufficiency as a cause for hypoglycemia identified left adrenal hemorrhage. EEG showed subclinical seizures in the form of epileptiform discharges isolated to the left posterior head region with no clear clinical correlate. Multiple medications were required to control seizures and included phenobarbital (20 mg/kg), levetiracetam (60 mg/kg), and fosphenytoin (20 mg/kg).
Neuroimaging and management considerations:
Magnetic resonance imaging (MRI) revealed an occlusion at the tip of the basilar artery and multiple discrete areas of acute focal infarction in the left posterior cerebral artery (PCA) territory, bilateral thalami, midbrain, bilateral cerebellum, and right occipital region (Figures 1 and 2). There was no evidence of vertebral dissection. Echocardiogram showed functionally bicuspid aortic valve with no abnormal shunting and no thrombus.
After discussion with hematology and interventional radiology, endovascular thrombectomy was not attempted due to multiple concerns including unknown age of stroke, risk of hemorrhage, and absence of safety evidence. Anticoagulation was deferred in context of thrombocytopenia and the cephalohematoma. Repeat neuroimaging 3 days and 8 days later showed no further ischemic injury and no thrombus propagation.
This complex case identified basilar artery thrombosis in a neonate with arterial ischemic stroke, which is an extremely rare occurrence in perinatal stroke literature6,7 and clinical practice. The baby presented with early refractory seizures that resolved within days, which is an expected pattern of acute symptomatic seizures in the context of NAIS. His encephalopathy was initially attributed to multiple anti-seizure medications with likely contributions from his bi-thalamic injury. Hypoglycemia has been associated with posterior circulation NAIS and often demonstrates a similar pattern of occipital injury4 though its role as an independent risk factor is uncertain8,9.
The presence of cerebellar infarcts suggested that the thrombus began more proximally and propagated to the basilar tip. In the absence of cardiac disease, the placenta was felt to be the most likely distal thromboembolic source.
- Anticoagulation in neonates with thrombosis has been shown to be safe and well-tolerated10,11, but was deferred in this case for thrombocytopenia and significant hemorrhage risk. In absence of anticoagulation, repeat neuroimaging is essential to rule out clot propagation12. Had repeat neuroimaging shows clot propagation in this case, our recommendation would have been to start anticoagulation as guided by our hematology colleagues.
- Mechanical thrombectomy in NAIS is reported in isolated cases7,13. A similar case of distal basilar artery occlusion was treated with thrombectomy at 14 hours of life7, after which the basilar artery recanalized but needed nimodipine for vasospasm, and the left vertebral artery occluded due to repeat catheterization requiring treated with anticoagulation. To avoid such iatrogenic complications and in the absence of evidence showing benefit, we did not pursue thrombectomy and opted for conservative management instead.
- Placental thromboembolism may be present for days or weeks prior to delivery, with resulting large vessel occlusion occurring anytime within that period. Thus, interventional therapies in NAIS are limited by the inability to determine stroke onset. Neonates additionally have small arteries that may be more susceptible to secondary dissection or hemorrhage.
- Hypoglycemia in this case may have contributed to occipital lobe injury and may also have been an indication of critical illness. Although this baby’s basilar artery occlusion is the primary etiology for his strokes, glycemic control is a key aspect of both primary and secondary ischemic injury8.
By 6 weeks of age, Baby M weaned off all anti-epileptic medication with no recurrence of seizures. He remained hypotonic but active, requiring NG feeds for poor suck.
Posterior artery strokes overall have good long-term neurodevelopmental outcome but higher risks of visual field deficits5. Baby M’s bilateral thalamic ischemic injuries further increase his risk of cognitive dysfunction and epileptic encephalopathy, such as continuous spike and wave in sleep (CSWS)14. Risks of neonatal thrombectomy are substantial and undefined with the theoretical benefit undetermined, requiring critical analysis of this acute intervention in such a vulnerable population.
- Raju TNK, Nelson KB, Ferriero D, Lynch JK, NICHD-NINDS Perinatal Stroke Workshop Participants. Ischemic perinatal stroke: summary of a workshop sponsored by the National Institute of Child Health and Human Development and the National Institute of Neurological Disorders and Stroke. Pediatrics. 2007;120(3):609-616. doi:10.1542/peds.2007-0336
- Mailo JA, Srivastava R, Jacob FD, Kirton A. What Do We Know About Perinatal Stroke? A review of current practices, outcomes, and future directions. Pediatr Stroke. 2021;1:26-62.
- Mineyko A, Kirton A. The black box of perinatal ischemic stroke pathogenesis. J Child Neurol. 2011;26(9):1154-1162. doi:10.1177/0883073811408312
- Dunbar M, Mineyko A, Hill M, Hodge J, Floer A, Kirton A. Population Based Birth Prevalence of Disease-Specific Perinatal Stroke. Pediatrics. 2020;146(5). doi:10.1542/peds.2020-013201
- van der Aa NE, Dudink J, Benders MJ, et al. Neonatal posterior cerebral artery stroke: clinical presentation, MRI findings, and outcome. DevMedChild Neurol. 2013;55:283-290.
- Govaert P, Dudink J, Visser G, Breukhoven P, Vanhatalo S, Lequin M. Top of the basilar artery embolic stroke and neonatal myoclonus. Developmental Medicine & Child Neurology. 2009;51(4):324-327. doi:10.1111/j.1469-8749.2008.03183.x
- Stracke CP, Meyer L, Schwindt W, Ranft A, Straeter R. Case Report: Successful Mechanical Thrombectomy in a Newborn With Basilar Artery Occlusion. Front Neurol. 2022;12:790486. doi:10.3389/fneur.2021.790486
- De Angelis LC, Brigati G, Polleri G, et al. Neonatal Hypoglycemia and Brain Vulnerability. Frontiers in Endocrinology. 2021;12. Accessed December 20, 2022. https://www.frontiersin.org/articles/10.3389/fendo.2021.634305
- Gu MH, Amanda F, Yuan TM. Brain Injury in Neonatal Hypoglycemia: A Hospital-Based Cohort Study. Clin Med Insights Pediatr. 2019;13:1179556519867953. doi:10.1177/1179556519867953
- Moharir MD, Shroff M, Stephens D, et al. Anticoagulants in pediatric cerebral sinovenous thrombosis: a safety and outcome study. Ann Neurol. 2010;67:590-599.
- Ferriero DM, Fullerton HJ, Bernard TJ, et al. Management of Stroke in Neonates and Children: A Scientific Statement From the American Heart Association/American Stroke Association. Stroke. 2019;50(3):e51-e96. doi:10.1161/STR.0000000000000183
- Srivastava R, Kirton A. Perinatal Stroke: A Practical Approach to Diagnosis and Management. Neoreviews. 2021;22(3):e163-e176. doi:10.1542/neo.22-3-e163
- Zeleňák K, Matasova K, Bobulova A, Matasova K. Mechanical and Aspiration Thrombectomy in a 2-day-old Neonate with Perinatal Stroke. Clin Neuroradiol. Published online October 13, 2021. doi:10.1007/s00062-021-01104-3
- Losito E, Battaglia D, Chieffo D, et al. Sleep-potentiated epileptiform activity in early thalamic injuries: Study in a large series (60 cases). Epilepsy Res. 2015;109:90-99. doi:10.1016/j.eplepsyres.2014.10.015
- Kirton A, Armstrong-Wells J, Chang T, et al. Symptomatic neonatal arterial ischemic stroke: the International Pediatric Stroke Study. Pediatrics. 2011;128(6):e1402-1410. doi:10.1542/peds.2011-1148
FIGURES & TABLES
Table 1: Prevalence of posterior circulation strokes in select original research studies of neonatal arterial ischemic stroke (NAIS). N, number of cases in study.
Figure 1: Representative MRI sequences showing acute ischemia. Axial DWI showing areas of restricted diffusion in the left occipital lobe (left PCA territory). Multifocal patchy areas of restricted diffusion in the bilateral thalami, left corticospinal tract, midbrain, superior cerebellar vermis, and bilateral cerebellar hemispheres pertaining to the areas of posterior circulation. Focal area of restricted diffusion noted in the right occipital region.
Figure 2: Angiographic evidence of basilar artery occlusion. Time-of-flight MRA shows occlusion at distal basilar artery proximal to the bifurcation (white arrows). The left P1 PCA and superior cerebellar artery are not visualized. P2 segment of left PCA reconstitutes through the anterior circulation but appears attenuated. There is reconstitution of the right PCA through anterior circulation but is also attenuated.
Srivastava – Basilar Artery Thrombosis