Clinical Reasoning: Wilbrand's Knee, Scotoma of Traquair, and Normal Tension Glaucoma

An otherwise healthy 63-year-old woman was given a diagnosis of normal tension glaucoma (NTG) in the right eye (OD) 2 months before presentation. Standard computerized perimetry showed a unilateral right hemianoptic temporal field defect. On examination visual acuity was preserved, intraocular pressure was normal, there was a right relative afferent pupillary defect (RAPD) with an asymmetric cupping of the disc, but no pallor. Brain magnetic resonance imaging (MRI) showed a meningioma compressing the right optic nerve at its junction with the chiasm. Compressive disorders on the anterior chiasm, albeit rarely, may cause cupping of the disc and unilateral temporal visual field defect (junctional scotoma of Traquair) with normal visual acuity that should be considered in the differential diagnosis of NTG.