Beware the midline scalp lump in a patient with retinal dystrophy

A 49-year-old woman with high myopia, microcornea, early-onset cataracts with lens dislocation, and long-standing retinal dystrophy presented for ophthalmic genetic evaluation.Fundus imaging showed extensive chorioretinal and macular atrophy with retinal pigmentation (A, B).She also reported a longstanding "sebaceous cyst" on her occiput awaiting excision (C).The ophthalmic findings raised suspicion of Knobloch syndrome.Given its association with midline occipital defects, excision of the scalp lesion was deferred and genetic testing undertaken.This identified biallelic loss-of-function variants in COL18A1, confirming the diagnosis.Subsequent MRI neuroimaging demonstrated a midline extracranial cystic structure with intracranial extension, consistent with an encephalocele (D), a recognised feature of this condition.This case highlights the importance of recognising systemic associations in inherited eye disease.Midline scalp lesions may reflect underlying structural abnormalities and warrant careful consideration.In this patient, timely clinical and