Online Articles: Case Report/Small Case SeriesThe Translaminar Pressure Gradient: Papilledema After Trabeculectomy Treated With Optic Nerve Sheath FenestrationRadke, Phillip M. MD*,†; Rubinstein, Tal J. MD*,†; Hamilton, Steven R. MD‡; Jamil, Annisa L. MD§; Sires, Bryan S. MD, PhD*,†Author Information *Allure Laser Center & Medispa, Kirkland †Department of Ophthalmology, University of Washington ‡Neuroscience Institute, Swedish Medical Center §Glaucoma Consultants Northwest at The Polyclinic, Seattle, WA Disclosure: The authors declare no conflict of interest. Reprints: Bryan S. Sires, MD, PhD, 625 4th Avenue, Suite 301, Kirkland, WA 98033 (e-mail: firstname.lastname@example.org). Journal of Glaucoma: October 2018 - Volume 27 - Issue 10 - p e154-e157 doi: 10.1097/IJG.0000000000001021 Buy Metrics Abstract Introduction: Trans-lamina cribrosa pressure has been postulated to be a contributor in the development of a glaucomatous optic nerve versus optic nerve edema, depending on the pressure gradient. Uncertainty remains in the therapeutic outcome of adjusting this gradient. Case Report: We discuss a unique case of idiopathic intracranial hypertension presenting as asymmetric optic disc edema following trabeculectomy. It was treated via optic nerve fenestration due to the patient remaining symptomatic on maximum tolerated acetazolamide. Intraocular pressure stabilized into target range and the optic nerve edema resolved. Conclusions: Rarely, intraocular pressure reduction can unmask elevated intracranial pressure, leading to optic nerve edema. Optic nerve sheath fenestration is a practical therapeutic modality to consider when treating this occurrence. Copyright © 2018 Wolters Kluwer Health, Inc. All rights reserved.