Bilateral normal tension glaucoma: Can this be nutritional?

Normal tension glaucoma (NTG) also known as low tension glaucoma, presents with optic nerve head and visual field damage in the absence of high intraocular pressure (<21 mmHg). There are several patients of NTG seen in our clinics who have repeatable visual field defects, which may or may not correlate with the disc appearance, but are labeled as glaucoma. Ruling out ischemic, nutritional, and other causes of one-time damage are important before diagnosing an NTG. We report 3 such cases that were misdiagnosed and referred as NTG. All three cases were not glaucomatous and had typical features of nutritional optic neuropathy. The typical clinical features, visual field and imaging abnormalities seen in these two conditions and their management is highlighted in this article. Misdiagnosis leads to inappropriate investigations and treatment, but more importantly would lead to worsening of undiagnosed underlying disease.