LAUSR

© Author(s) (or their employer(s)) 2023. No commercial reuse. See rights and permissions. Published by BMJ. A 37yearold woman developed increasingly frequent bifrontal migrainous headaches, some of which woke her from sleep. Neurological and ophthalmological examinations were normal. We organised brain imaging to exclude a structural cause. MR scan of brain showed a spatially extensive right hemispheric abnormality (figure 1A–C); axial T2weighted (figure 1A,B) and coronal fluidattenuated inversion recovery sequences (figure 1C) showed high signal within the frontoparietal subcortical white matter of the right hemisphere. Juxtacortical white matter was preserved, with no lateralised volume loss. Screening blood tests for known causes of white matter disease or leukodystrophy were normal or negative (including a clotting screen, lipid profile, haemoglobin A1c, verylongchain fatty acids, pristanic acid, phytanic acid, amino acid profile, antinuclear antibodies, antimyeloperoxidase antibodies, antiproteinase 3 antibodies, antibeta2 glycoprotein1 antibodies, anticardiolipin antibodies, serology for HIV and for syphilis, and white cell enzymes). Neuroradiological discussions were inconclusive. In view of the lateralised (rather than global) findings, and in the absence of ongoing symptoms or neurological deficit, we did not request genetic screening tests for white matter disorders. Her headache symptoms resolved on amitriptyline. We had noted some asymmetry of her lower face (figure 1E: photographs aged 37 years), and so enquired further into her childhood history. Her paediatric records detailed congenital facial asymmetry in keeping with right hemifacial microsomia (a craniofacial microsomia;