Introduction Idiopathic intracranial hypertension (IIH) is a challenging disorder of intracranial hypertension in the absence of an intracranial mass, hydrocephalus, or other identifiable cause. The incidence is approximately 0.9/100.000/year rising to 13/100.000/year in overweight women between 20 and 44 years of age. Less frequently, it is seen in children and overweight men. 1-5 Due to increasing prevalence of the obesity over the last years, IIH has been also on the rise. This increase is widely seen in our country, even though there still has not been painstaking information and research over the issue. The symptoms usually progress in a few weeks to months, though fulminant cases have also been reported. IIH has a variable course ranging from a short benign self-limiting syndrome to more aggressive syndromes that proceed to blindness in a short period of time. 5-7 The characteristic features of IIH include headache, visual loss, which can be irreversible if not treated promptly. 8,9 Visual loss can occur anytime along the course of the disease but is often insidious as central vision is spared until late in the course of the illness. Some degrees of visual impairment are detected in up to 90% of patients by perimetry at the time of diagnosis, however only about one third complain from the vision loss. 6,10,11 As long as severe and prolonged papilledema causes retinal breakdown or macular impairment, the visual acuity will be preserved. 6,12-14 According to significant role of vision system concerned to environment and possibility of irreversible complication if not treated and subsequent burden on society and health system, the early diagnosis and proper treatment is in paramount of importance. Until now, little research has been conducted on relationship of cerebrospinal fluid (CSF) pressure and visual field defect and the results are controversial. In the study of Baheti et al there was not a dramatic difference between CSF pressure in patients with either normal or subtle visual impairment or severe visual impairment. 5 In contrast, Saindane et al in their study revealed that, in patients with severe visual impairment, the CSF pressure was higher whether in the form of reduced visual acuity Relationship of Opening CSF Pressure and Visual Field Defect in Idiopathic Intracranial Hypertension Sepideh Paybast, Farhad Assarzadegan, Behnam Safarpoor Lima, Mohsen Koosha* Department of Neurology, Imam-Hossein Hospital, Shahid-Beheshti University of Medical Science, Tehran, Iran Abstract Background: Idiopathic intracranial hypertension (IIH) is an increased intracranial pressure with normal cerebrospinal fluid (CSF) characteristic in the absence of identifiable causes. The most important complication of this disorder is visual impairment. So far, no comprehensive study has been done on the relationship between the opening CSF pressure and visual field defect in IIH. Methods: In this study, 35 patients with increased intracranial pressure who fulfilled modified Dandy’s criteria underwent ophthalmologic examination and lumbar puncture. The opening CSF pressure was categorized into mild (25-30), moderate (30-40) and severe (>40). The degree of visual field defect was reported both quantitatively and qualitatively. Eventually, the statistical relationship was established among these variables. Results: The mean opening CSF pressure was 33.71 CmH2o. Twelve patients had minor CSF pressure, whereas in 14 and 9 patients the CSF pressure was respectively moderate and severe. There was not statistically significant relationship between the visual field defect and CSF pressure. The most common patterns of visual field involvement were enlarged blind spot and peripheral restriction. Conclusion: The most important morbidity in IIH is visual impairment. According to the findings, the visual field impairment is not pertinent to CSF pressure. In other words, neither high CSF pressure predicts intense visual defect, nor low CSF pressure indicates minimal visual impairment. Keywords: Idiopathic intracranial hypertension (IIH); Perimetry; Visual field; CSF pressure *Correspondence to Mohsen Koosha, MD, Department of Neurology, Imam-Hossein Hospital, Shahid-Beheshti University of Medical Science, Tehran, Iran. Email: mohsenkoosha63@gmail.com Published online 19 June 2018 Int Clin Neurosci J. 2018 Spring;5(2):51-54 Original Article International Clinical Neuroscience Journal Open Access Scan to access more free content © 2018 The Author(s). This is an open access article distributed under the terms of the Creative Commons Attribution License (http:// creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. doi:10.15171/icnj.2018.10 Citation: Paybast S, Assarzadegan F, Safarpoor Lima B, Koosha M. Relationship of opening CSF pressure and visual field defect in idiopathic intracranial hypertension. Int Clin Neurosci J. 2018;5(2):51-54. doi:10.15171/icnj.2018.10.