Presentation
Left facial numbness.
Patient Data
Florid features consistent with known idiopathic intracranial hypertension (IIH). Increased optic nerve sheath fluid bilaterally with flattening of the posterior globe, more so on the right, suggestive of papilledema. The pituitary fossa is expanded and mostly empty with compressed pituitary tissue inferiorly. No evidence of dural venous sinus thrombosis, however there is prominent stenosis of the distal transverse sinuses bilaterally. The right Meckle cave is normal. The left Meckle cave is small, compressed from above, with little if any CSF around the trigeminal nerve. Bilateral, left greater than right, medial sphenoid meningocoeles without evidence of fluid in sphenoid sinus to suggest CSF leak. No intracranial hemorrhage or extra-axial collection. No diffusion restriction abnormality. No abnormal contrast enhancement. Major intracranial vessels appear normal. There are few scattered small T2/FLAIR hyperintense white matter lesions, within normal range for age. MRA is unremarkable.
Conclusion:
Features are those of idiopathic intracranial hypertension, with compression of the left trigeminal nerve in Meckle's cave the likely cause of symptoms.
Case Discussion
This patient had established idiopathic intracranial hypertension (IIH) on lumbar puncture, with classical imaging features. The compression of trigeminal cave is unusual, as expansion of the cave is a more common finding.