Clinical question: 32M with new onset anisocoria, eval for intracranial processSigns and Symptoms: anisocoria The CSF spaces are appropriate for the patient's stated age with no midline shift. The left lateral ventricle is asymmetrically larger than the right lateral ventricle. The left anterior septal vein appears to drain on the right sideNo abnormal mass lesions are appreciated intracranially. No intracranial hemorrhage is identified. No edema is identified within the brain parenchyma.Normal vascular flow voids are present in the distal carotid and vertebral arteries, the basilar artery and the proximal anterior, middle and posterior cerebral arteries as well as the internal cerebral veins and superior sagittal sinus. The right ICV is larger than the left ICV. Left sigmoid sinus is larger than the right sigmoid sinus. The left BVR is larger than the right BVR.The visualized portions of the paranasal sinuses demonstrate some minor mucosal thickening in the left maxillary sinus. The visualized portions of the mastoid air cells are clear. The visualized portions of the orbits are intact.
Asymmetry of the lateral ventricles is present without any obvious underlying cause. This is a frequent finding an can be considered a variant of normal. The fact that there is associated underlying anomalous drainage suggests that this could be congenital.