RESUMEN
BACKGROUND: Diffuse cerebral angiomatosis (DCA) is a diffuse infiltration of normal brain by complex vascular structures. It differs from arteriovenous malformations (AVMs) that are composed of a nidus of vessels through which arteriovenous shunting occurs without interposed functional brain parenchyma. A rare subgroup of AVMs is diffuse with no recognizable nidus with functional neuronal tissue interspersed within the malformed vessels. We present a rare association of DCA and cerebral arterial aneurysm, which dramatically influenced the patient's prognosis. CASE DESCRIPTION: A 43-year-old male patient with right hemispheric diffuse cerebral angiomatosis presented with a ruptured basilar tip aneurysm that was successfully embolised. Unfortunately, the patient developed a locked-in syndrome. CONCLUSION: The present report shows a possible association between diffuse cerebral angiomatosis and cerebral aneurysms, but this association appears to be less strong than it is with other AVMs.