Urgent computed tomography angiography in paediatric stroke

Abstract

Aim: To improve delivery of acute therapies for acute ischaemic stroke (AIS).

Method: We identified factors influencing the speed of diagnosis and delivery of acute therapies in a prospective cohort of 21 children with suspected AIS (eight with AIS, 13 stroke mimics) and explored them in a retrospective cohort with confirmed AIS.

Results: Approximately half of the prospective and total AIS cohorts presented with acute, sustained hemiparesis, and were diagnosed relatively quickly. AIS was suspected and diagnosed more slowly in the half presenting with symptoms other than sustained hemiparesis. Thirty-one out of 51 patients with AIS (19 females, 32 males, mean age 8 years 6 months, SD 5 years 4 months) had arterial abnormalities identified by computed tomography angiography (CTA) or magnetic resonance angiography (MRA): 11 with large vessel occlusion, six with dissection, five with moyamoya disease, nine with other arteriopathies. Among these patients, those initially imaged with CTA were diagnosed more quickly than those with initial magnetic resonance imaging/angiography, which facilitated thrombectomy and thrombolytic therapy. Twenty out of 51 had AIS without arterial abnormalities on CTA or MRA: eight with lenticulostriate vasculopathy and 12 with other small-vessel AIS. Among these patients, 80% were ineligible for thrombolysis for reasons beyond delay to diagnosis, and all showed good outcomes with supportive treatments alone.

Interpretation: Clinical features at presentation influence rapidity with which childhood AIS is suspected and diagnosed. Readily available CTA can direct thrombectomy in patients with large vessel occlusion and thrombolysis in most, but not all, eligible patients.

What this paper adds: Children with acute ischaemic stroke (AIS) commonly present with symptoms other than sustained hemiparesis. Stroke is more slowly recognized in these patients, which limits potential therapies. Computed tomography angiography (CTA) accurately identifies AIS with large vessel occlusion, enabling timely endovascular thrombectomy. CTA is sufficient to direct thrombolytic therapy in most eligible children. Most childhood AIS without arterial abnormalities identified by CTA had good outcomes.

FIGURE 1

Three clinical scenarios of large vessel occlusion identified by computed tomography angiography (CTA). Imaging representing three different clinical scenarios related to large vessel occlusion (LVO) from the prospective cohort (Table 1). (a–d) Patient 1. (a) Initial non‐contrast (brain) computed tomography (NCCT) at local hospital 95 minutes after typical onset of right hemiparesis and aphasia, shows subtle loss of grey‐white differentiation in the anterior left middle cerebral artery (MCA) territory. (b) CTA maximal intensity projection image shows occlusion at distal left M1 (first division of middle cerebral artery) (open red arrow). (c) Tissue plasminogen activator started at local hospital and transported to Sydney Children's Hospital (SCH). Endovascular thrombectomy (EVT) completed 251 minutes after symptom onset. Left internal carotid artery digital subtraction angiography image shows re‐established flow through left M1. (d) Magnetic resonance imaging (MRI) T2‐weighted axial image shows residual left frontal infarction (slender red arrow). (e–i) Patient 2. (e) Normal NCCT 88 minutes after onset of long seizure. (Had CTA been performed, the distal right internal carotid artery occlusion may have been identified and urgently treated.) Transported intubated and sedated to SCH. (f,g) Left hemiparesis noted and urgent NCCT/CTA 517 minutes after symptom onset shows established, large right MCA infarct (circled in red; scores of 2 on Alberta Stroke Program Early CT ¹⁰ ) and occlusion of distal right internal carotid artery (open red arrow). EVT not offered. (h) MRI diffusion‐weighted axial image shows extensive right MCA infarction comparable to image in (f). (i) Delayed MRI T2‐weighted axial image shows evolution of the infarct, which required hemicraniectomy for malignant swelling. (j–m) Patient 3. (j) After hours of unrecognized posterior fossa symptoms in a tiny rural hospital, telephone consultation suggested posterior circulation AIS. Electronic review of the local NCCT by the SCH team identified the dense basilar artery (green arrow on this axial NCCT), which prompted urgent transfer to SCH. (k) CTA maximal intensity projection image shows occlusion (absence) of the basilar artery (open red arrow). (l) EVT re‐established flow through the basilar artery (open red arrow). (m) Subsequent MRI T2 axial image shows residual left pontine infarction (slender red arrow)