Clinical Study Optic Nerve Sonography in the Diagnostic Evaluation of Pseudopapilledema and Raised Intracranial Pressure: A Cross-Sectional Study Masoud Mehrpour, 1 Fatemeh Oliaee Torshizi, 2 Shooka Esmaeeli, 3 Salameh Taghipour, 2 and Sahar Abdollahi 2 1 Department of Neurology and Stroke Center, Firoozgar General Hospital, Iran University of Medical Sciences, Tehran 1449614535, Iran 2 Iran University of Medical Sciences, Tehran 1449614535, Iran 3 Students’ Scientifc Research Center (SSRC), Tehran University of Medical Sciences, Tehran 1417755331, Iran Correspondence should be addressed to Shooka Esmaeeli; sh.esmaeeli@gmail.com Received 28 September 2014; Revised 21 December 2014; Accepted 9 January 2015 Academic Editor: Mamede de Carvalho Copyright © 2015 Masoud Mehrpour et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Introduction. Diferentiating pseudopapilledema from papilledema which is optic disk edema and a result of increased ICP (intracranial pressure) is important and can be done with noninvasive methods like orbital ultrasound examination. Method. Tis was a cross-sectional study in which patients with optic nerve head swelling were referred for LP exam afer optic nerve head swelling diagnosis confrmation and having normal brain imaging (CT scan). Before LP (lumbar puncture) exam the patients were referred for optic nerve ultrasound test of both eyes. Results. Considering 5.7 mm as the upper limit for normal ONSD (optic nerve sheath diameter), sensitivity and negative predictive value of optic sonography in diagnosis of pseudopapilledema are 100% for both eyes. Calculated accuracy validity of ONSD measurement in detecting pseudopapilledema is 90% for the right eye and 87% for the lef eye. Conclusion. Our study demonstrated a close correlation between optic nerve sheath dilation on ocular ultrasound and evidence of elevated ICP with optic disk swelling. With the aid of noninvasive diagnostic tests we can avoid unnecessary concerns along with expensive and invasive neurological investigations while targeting the correct diagnosis in bilateral optic disk swelling. Our study showed optic nerve sonography as a reliable diagnostic method for further usage. 1. Introduction While papill edema is Optic Nerve Head (ONH) edema sec- ondary to increased intracranial pressure (ICP), pseudopa- pilledema is apparent ONH swelling that stimulates some features of papill edema but is secondary to an underlying, usually benign, process which can be congenital anomalies associated with the disk elevation, hyperopic disk, or ONH drusen. Acquired disk edema includes papilledema as well as other causes of optic disk edema such as optic neuritis, anterior ischemic optic neuropathy, malignant hypertension, infltrative optic neuropathies, and compressive optic neu- ropathy [1]. ONH drusen accounts for 75% of clinical cases of pseu- dopapilledema, occurs in up to 2% of general population, and is congenitally inherited; it has the same prevalence between men and women and is usually bilateral. Patients with ONH drusen are usually asymptomatic but visual feld defects can be present. Diagnosis is most reliably made by orbital ultrasound examination [1]. Clinical features in pseudopapilledema difer from papill- edema; pseudopapilledema patients usually have no visual Hindawi Publishing Corporation Neurology Research International Volume 2015, Article ID 146059, 4 pages http://dx.doi.org/10.1155/2015/146059