Patent Foramen Ovale: Red Flag in Radiologically Isolated Syndrome

Objectives: To investigate the association of white matter lesions suggestive of demyelinating disease in magnetic resonance imaging (MRI) with patent foramen ovale (PFO) in migraine patients, with and without aura.
Materials: 22 migraine patients, 19 females and 3 males, with MRI evidence of white matter lesions suggestive of demyelinating disease. In 16 patients Barkhof criteria for dissemination in space were respected. For this reason, all the patients practiced further diagnostics including lumbar puncture, autoimmunity panel, thrombophilic evaluation, cardiological evaluation to detect the presence of PFO. Instrumental and clinical follow-up over three years was practiced and MIPAV software was used to analyse MRI imaging.
Results: 13 of 22 patients (59%) had PFO. Significant association was found between PFO and migraine with visual aura (p=0.03) and thrombophilia (p=0.04). None of them had oligoclonal bands in csf (p=0.014). No difference in number, volume and distribution of the lesions between the patients with and without PFO was noticed and 11 out of 16 patients carrying Barkhof criteria for disseminating in space had PFO. The follow up showed a stationary lesion load in all PFO patients, no infratentorial or spinal cord lesions and no enhancement at any time. The presence of PFO didn’t affect the lesions localization (periventricular, iuxtacortical, frontal, occipital, temporal or parietal) and corpus callosum lesion was never detected.
Discussion and conclusions: Migraine is often one of the main symptoms leading the patient to perform MRI, discovering, in most of the cases, white matter lesions of unspecific significance and placing always demyelinating diseases in differential diagnosis. Our study underlines the potential pathogenetic role of PFO in generating white matter lesions in migraine patients (59%), particularly in those with visual aura and thrombophilia. On the other side, with the evidence that 11 out of 16 patients carrying Barkhof criteria for disseminating in space had PFO and no clinical and instrumental diagnosis of demyelinating disease, we state that cardiologic evaluation represents a cardinal toll in differential diagnosis of RIS.