Images A to D: Fetal T2 Weighted images showing multiple porencephalic cysts with enlarged lateral ventricles showing irregular margins, old infarcts /hemosiderin staining in cerebral white matter and gliosis in caudothalamic groove.

Images E to H: Post-natal scans confirm above findings. Susceptibility Weighted Images ( G and H) show multiple areas of hemosiderin staining in deep cerebral white matter and choroid plexus and ependymal lining of both lateral ventricles.

Original

Captions

Images A-D: Fetal MRI at 33 weeks of gestation and images E-H: Postnatal MRI scan at day 5 of life

Images A-D: Fetal MRI at 33 weeks of gestation and images E-H: Postnatal MRI scan at day 5 of life

COL4A1 Associated Multiple Chronic Intraparenchymal Hemorrhages With Porencephalic Cysts

• vMutation in COL4A1 gene leads to group of conditions known as COL4A1 related disorders. COL4A1 gene encodes for type IV collagen and is expressed in brain, eyes, muscles and kidneys [1].
• vOur case shows porencephaly due to antenatal intracerebral haemorrhages which do not follow vascular territories. Porencephaly is characterised by fluid filled cavities within cerebral parenchyma due to antenatal or perinatal intraparenchymal haemorrhages. Porencephaly can also be associated with periventricular leukoencephalopathy, lacunar infarct, microbleeds and calcifications[2].
• vThe takeaway is, consider COL4A1 gene mutation when encountering cerebral infarction or intraparenchymal haemorrhages (which do not follow vascular territory ), ventriculomegaly or focal parenchymal defects (porencephalic cysts) on prenatal imaging.

Differential Diagnosis

1. COL4A2 gene mutation: similar imaging appearance, only genetics helps to differentiate.
2. SAMHD1 gene mutation: characterised by cerebral vasculopathy- stenosis/ aneurysms of vessels , chronic   ischemic changes, Moya Moya pattern, infarcts and hemorrhages.
   MRA in our case was normal.

References :

1. England, E.C., Cornejo, P., Neilson, D.E. et al. Fetal brain small vessel disease 1 caused by a novel mutation in the COL4A1 gene. Pediatr Radiol 51, 480–484 (2021). https://doi.org/10.1007/s00247-020-04847-2
2. Plaisier E, Ronco P. COL4A1-Related Disorders. 2009 Jun 25 [Updated 2016 Jul 7]. In: Adam MP, Feldman J, Mirzaa GM, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2025. Available from: https://www.ncbi.nlm.nih.gov/books/NBK7046.