2.1 Preoperative evaluation
Patients with traumatic optic neuropathy were admitted under neurosurgery department and references to ENT department were sent at least 24 hours after admission. However, most of these cases might already be started on high dose corticosteroids. Patients were planned for optic nerve decompression when there is radiological evidence of fracture involving optic canal (Fig. 1) and failed medical management. Patients with radiological evidence of fracture segment impingement on optic nerve and deteriorating vision were straight away taken up for EOND and not waited for medical decompression.
Ophthalmological evaluation for visual assessment (Table I)10 and fundoscopy were done for these patients. Fundoscopic examination may provide helpful information and avoid unnecessary surgery. If this examination displays total atrophy of the optic nerve (which indicate a pre existing pathology), there is no reason for EOND, because restoration of vision is impossible. Complete atrophy occurs 2 to 3 weeks after trauma. However, injuries to the intraocular or intraorbital portions of the optic nerve result in changes that may present very rapidly. Fundoscopic examination also is very helpful in ruling out etiologies of decreased vision other than injury to the optic nerve, such as retinal edema, choroidal rupture, retinal detachment, or vitreous hemorrhage11. Relative afferent pupillary defect which is a sign optic neuropathy is seen in majority of these patients. All patients who were started on high dose corticosteroids were observed for any visual improvement and not waited for more than 72 hours so that further intervention may be planned as early as possible. Those with improvement were continued with medical management. But those with no improvement or with visual deterioration were given the option of surgery. Some patients refused the surgery and unfortunately some patients could not be taken right away for surgery as they had other life threatening conditions to be treated and EOND had to be prolonged for the well being of the patient. Hence such cases were taken after 72 hours once the patient became stable for surgery. Preoperative consent regarding visual improvement and prognosis were obtained after discussing the possible complications. During the initial years of our study patients who were taken up for optic nerve decompression after 7 days with no light perception did not show any improvement. Hence in the later years, such patients were excluded.