Volume 17, Issue 7, Pages 609-617 (July 2018) Prevalence of patent foramen ovale in cryptogenic transient ischaemic attack and non- disabling stroke at older ages: a population-based study, systematic review, and meta- analysis  Sara Mazzucco, MD, Linxin Li, DPhil, Lucy Binney, MD, Prof Peter M Rothwell, FMedSci  The Lancet Neurology  Volume 17, Issue 7, Pages 609-617 (July 2018) DOI: 10.1016/S1474-4422(18)30167-4 Copyright © 2018 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license Terms and Conditions

Figure 1 Prevalence of PFO in patients with cryptogenic events compared with patients with events of known cause Meta-analyses of the prevalence of PFO in patients with cryptogenic events compared with patients with events of known cause, stratified by imaging modalities, (A) overall and (B) in older patients, according to study author's definition. PFO=patent foramen ovale. OR=odds ratio. Bubble-TCD=contrast-enhanced transcranial Doppler. OXVASC=Oxford Vascular Study. *Age cutoff points for the older group in different studies ranged between 40 and 60 years. The Lancet Neurology 2018 17, 609-617DOI: (10.1016/S1474-4422(18)30167-4) Copyright © 2018 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license Terms and Conditions

Figure 2 Meta-analyses of the prevalence of PFO stratified by screening modality PFO=patent foramen ovale. Bubble-TCD=contrast-enhanced transcranial Doppler. OXVASC=Oxford Vascular Study. The Lancet Neurology 2018 17, 609-617DOI: (10.1016/S1474-4422(18)30167-4) Copyright © 2018 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license Terms and Conditions