Unilateral papilledema in idiopathic intracranial hypertension: A rare entity.

Idiopathic Intracranial Hypertension (IIH), also known as pseudotumor cerebri is a clinical syndrome of unknown etiology, which typically affects young, obese women of childbearing age and is characterized by increased intracranial pressure and bilateral papilledema. Unilateral and highly asymmetrical papilledema is a rare presentation in IIH occurring in less than 4% of patients with definite IIH and can poses a diagnostic challenge for the treating physician as it usually raises the suspicion of localized ocular pathology. As per current consensus, papilledema results in stasis of axoplasmic transport due to mechanical compression, leading to secondary vascular changes of venous dilation and hemorrhage. Given this mechanism, the underlying reasons for unilateral and asymmetrical papilledema remain unclear.