FACTORS AFFECTING VISUAL OUTCOME IN INDIRECT TRAUMATIC OPTIC NEUROPATHY – A RETROSPECTIVE NON-RANDOMIZED STUDY Dr. Tharini.S* MS, Senior resident Department of Ophthalmology, JIPMER, Puducherry, India.*Corresponding Author Original Research Paper Ophthalmology INTRODUCTION Traumatic optic neuropathy (TON) is a rare cause of permanent visual disability following trauma. In recent years the incidence of TON has [1] increased ranging from 2% to 5%. Injury to the optic nerve can be direct or indirect due to the transmitted forces from head injury or orbital injury. The proposed mechanisms of indirect injury include [2-4] [2, 5] traction on the optic nerve , optic nerve compression by edema and impingement of the optic nerve by bony spicules from the [3] fractured optic canal causing vascular compromise. But the exact pathogenesis still remains unclear. The treatment options include observation, low dose steroids or high dose steroids and surgical decompression, although none of the modalities were proven superior. [6] The visual outcome in TON patients is unpredictable and decision to treat or not is yet a question to be answered. The purpose of our study was to obtain the demographic prole of TON and to nd whether low dose steroids and surgical treatment showed any benecial effect thereby to analyze the possible factors that can affect the visual outcome in patients with indirect TON. MATERIALS AND METHODS A retrospective review of medical records of patients admitted with the diagnosis of indirect TON, in a tertiary care centre in South India, from February 2016 to February 2018 was conducted. All patients who presented within 8 hours of injury, who had a minimum follow up of one month were included in this study. Whereas, those with direct TON, altered sensorium, associated ocular injuries contributing to visual loss were excluded from the study. Diagnosis of TON was based on acute drop in vision following trauma, with Relative Afferent Pupillary Defect (RAPD) or loss of color vision in Ischihara's pseudo- isochromatic chart or visual eld defect. Computed Tomography (CT) scan of orbit was done to look for bony impingement of the optic nerve. Patients without bony impingement of optic nerve were treated with low dose intravenous Methyl Prednisolone 250 mg every sixth hourly for 3 days, followed by oral Prednisolone 1mg/kg/day for 11 days. Those who had bony impingement of optic nerve from medial wall of optic canal were treated with nasal endoscopic surgical decompression. Visual acuity, color vision, RAPD and optic disc evaluation was done on rst three days and at the end of 2 weeks and one month. Visual recovery was dened as improvement in 2 Snellen lines, 2 weeks post injury. Statistical analysis was done using SPSS for Windows, version 20.0 (SPSS Inc., IBM, Armonk, NY, USA). The categorical variables were expressed in percentage and their association with visual outcome was analyzed using Chi square test. P value of less than 0.05 was considered to be statistically signicant. RESULTS During the study period, 53 consecutive patients were diagnosed with indirect TON, of them 6 had record inadequacy and 26 had altered sensorium with severe brain injury, they were excluded from the study. Hence, the records of remaining 21 patients were analyzed. There were 19 males (90.4%) and 2 females (9.5%). Age group of the patients ranged from 13-75 years (Mean-31.6 years). TON occurred in right eye in 11 patients (52.3%) and in left eye in 10 (47.6%). None of the patients had bilateral injuries. Road Trafc Accident was the most common cause of TON, identied in 17 patients (95.23%). Other causes included self-fall injury in 9.5% (n=2) and trauma due to physical assault in 9.5 % (n=2). Time of presentation varied from 1-7 hours (mean-3.6 hours). Out of 21 patients, 7 (33.33%) had associated orbital wall fractures, 4 (19.04%) had lid laceration, 5 (23.8%) had lid edema and 1 (4.76%) had vitreous hemorrhage and 12 (57.14%) patients had polytrauma. The demographic prole of TON patients is summarized in Table-1. TABLE 1. Demographic profile of the study group Vision at presentation was PL+ (Perception of light) and above in 8 (37.1%) and PL- (No perception of Light) in 13 (61.9%) patients. On radiological imaging, 6 patients (28.5%) had associated orbital wall fractures, 3 (14.2%) had facial fractures without orbital involvement, 8 patients (38.09%) had associated intracranial pathology, and 4(19.04%) patients had no other pathology except vision loss. 18 patients (85.7%) without bony impingement of optic nerve were treated with low dose steroids and 3 patients (14.2%) with medial bony impingement were treated with endoscopic surgical decompression. INDIAN JOURNAL OF APPLIED RESEARCH 7 Volume - 10 | Issue - 9 | September - 2020 | . PRINT ISSN No 2249 - 555X | DOI : 10.36106/ijar Purpose To study the demographic prole and factors associated with visual outcome in patients with indirect traumatic optic neuropathy. A retrospective study of patients admitted with indirect traumatic optic neuropathy, in a Methods tertiary care centre in South India, from February 2016 to February 2018 was conducted. Patients with bony impingement on the optic nerve were treated with endoscopic surgical decompression and the rest were treated with low dose steroids. Visual acuity was assessed at presentation, 2 weeks and 3 months. The mean age of the patients was 31.6 years (13-75 years). 19(90.4%) patients were male and road trafc accident Results (95.23%) was the most common cause of injury. Mean time of presentation was 3.6 hours ( 1-7 hours) Vision at presentation was perception of light and above in 8(3.1%) and no perception of Light in 13(61.9%) patients. Visual improvement was seen in 4 out of 18 patients (22.2%) in the steroid group and 1 out of 3 patients (33.3%) in the surgery group. Visual acuity at presentation was signicantly associated with nal visual outcome (P=0.047). Our study demonstrated that visual acuity at presentation was the only factor associated with nal vision, Conclusion irrespective of associated injuries and treatment modalities. ABSTRACT KEYWORDS : Traumatic optic neuropathy, visual outcome, low dose corticosteroids Dr. Subashini Kaliaperumal MS,DNB,FRCS(Glasgow), Professor & HOD, Department of Ophthalmology, JIPMER, Puducherry, India. Dr.Ramesh Babu K MS , Professor, Department of Ophthalmology, JIPMER, Puducherry, India. Demographic data Classification Number (n) % Age <25 >25 8 13 38 62 Gender Male Female 19 2 90 10 Etiology RTA Fall Assault 17 2 2 81 9.5 9.5 Time of presentation (hrs) <= 4 hrs >4 hrs 15 6 71 29 Radiological ndings Orbital wall fractures Facial fractures other than orbit Intracranial pathology Nil pathology 6 3 8 4 28.5 14.2 38.09 19.04