International Journal of Ophthalmology and Clinical Research Research Article: Open Access ClinMed International Library Citation: Sekeroglu HT, FEBO, Turan KE, Arslan U, Sener EC, et al. (2014) Etiology of Fourth and Sixth Nerve Palsies: a Single Ophthalmology Clinic’s Perspective. Int J Ophthalmol Clin Res 1:005 Received: September 06, 2014: Accepted: December 20, 2014: Published: December 29, 2014 Copyright: © 2014 Sekeroglu HT. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Sekeroglu et al. Int J Ophthalmol Clin Res 2014, 1:1 ISSN: 2378-346X Etiology of Fourth and Sixth Nerve Palsies: a Single Ophthalmology Clinic’s Perspective Hande Taylan Sekeroglu 1 *, FEBO, Kadriye Erkan Turan 1 , Umut Arslan 2 , Emin Cumhur Sener 1 and Ali Sefk Sanac 1 1 Hacettepe University Faculty of Medicine, Department of Ophthalmology, Ankara, Turkey 2 Hacettepe University Faculty of Medicine, Department of Biostatistics, Ankara, Turkey *Corresponding author: Hande Taylan Sekeroglu, MD, FEBO, Hacettepe University, Faculty of Medicine, Department of Ophthalmology, Ankara, Turkey, Tel: +90 532 775 21 55; Fax: + 90 312 309 41 01; E-mail: h_taylan@yahoo.com Introduction Patients with paralytic strabismus comprise an important number of patients of ophthalmology clinics as well as of neurology and neuroophthalmology clinics. Te etiology of the palsy of fourth and sixth nerves may be numerous and difer from one clinic to other in terms of patients’ demographics and referral pattern. Te purpose of the study was to ascertain the etiology of fourth and sixth nerve palsies in an ophthalmology clinic and to defne the clinical features. Materials and Methods Te series consist of patients with paralytic strabismus due to fourth or sixth nerve palsies who were seen in Strabismus Clinic between January 2001 and January 2011. Te medical records of patients were reviewed upon approval of the institutional ethics comittee was obtained. Demographic data and etiology of the palsy were recorded. All patients having acquired nerve palsy were referred to neurology department in order to elucidate the underlying causes. Cases were classifed on the basis of etiology as: congenital, trauma, vascular disease (hypertension and diabetes mellitus), intracranial mass, other (lymphomas of the central nervous system, acute myeloblastic lymphoma) and undetermined. Te patients were divided into two groups according to the type of the nerve palsy they had. Patients with fourth nerve palsy were classifed as CN4 group and patients with sixth nerve palsy were categorized as CN6 group. Statistical analyses were performed using SPSS sofware for Windows version 15.0 (Statistical Package for the Social Sciences, SPSS, Inc., Chicago, IL). Arithmetic mean, standard deviation, median, range, frequency and percentage were used as descriptive statistics. Comparisons were made by Wilcoxon signed rank, Mann Whitney and Pearson chi-square tests. Results were accepted as statistically signifcant when p was <0.05. Results One hundred and seventy six patients with fourth (103/176) and sixth nerve palsies (73/176) were enrolled in the study. Te mean age, gender and laterality distribution within groups were described in detail in Table 1. When the mean age of each group was compared, the diference between two groups was found as signifcant. (p=0.001) Patients with sixth nerve palsy were signifcantly older than those who had fourth nerve palsy. Te median follow up time was 2 years (1-4) for each group. Te underlying etiologies for palsies were shown in Table 2. Te leading determined etiological factor was congenital palsy in CN4 group (39/103, 37.9%) and trauma in CN6 group (18/73, 24.7%). Discussion In the present study, a retrospective review of cases with fourth and sixth nerve palsies was performed in a strabismus clinic. Many reports are available in the literature concerning etiology of cranial Abstract Purpose: To ascertain the etiology of fourth (CN4) and sixth nerve palsies (CN6) in an ophthalmology clinic. Methods: This retrospective study consisted of 176 patients with fourth and sixth nerve palsies in a strabismus clinic. Demographic features and etiology were recorded. Results: One hundred and three patients with fourth nerve palsy and 73 patients with sixth nerve palsy were enrolled in the study. The median follow up was 2 (1-4) years. The most common cause of the palsy was congenital palsy in CN4 group (37.9%) and trauma in CN6 group (24.7%). Conclusions: Trauma and congenital palsies were the leading causes of fourth and sixth nerve palsies as described in the literature. Keywords Cranial nerve palsy, Fourth nerve palsy, Paralytic strabismus, Sixth nerve palsy