Prevalence and Risk Factors of Dry Eye Disease after Refractive Surgery

PURPOSE: To assess the prevalence and the risk factors of dry eye disease after refractive surgery. METHODS: A retrospective study was performed on 180 eyes of 98 patients based on medical records. Those who had tear break-up time less of than 5 seconds or had an Oxford stain scale equal to or greater than 2 were defined to have dry eye disease. We analyzed the prevalence of dry eye, compared demographic and clinical features of the dry eye group and normal group, and found risk factors of dry eye after refractive surgery. RESULTS: The prevalence of postoperative dry eye was 62.2%. Compared to the normal eye group, the dry eye group had a significantly higher proportion of women (p = 0.016), older age (p = 0.001), and thin cornea (p = 0.002). The most significant risk factor of dry eye after refractive surgery was presence of dry eye before refractive surgery (odds ratio [OR] = 9.02, confidence interval [CI] = 3.8-21.4). Old age was also found to be an independent risk factor of dry eye after refractive surgery (OR = 1.06, CI = 1.01-1.11). CONCLUSIONS: The risk of dry eye after refractive surgery was increased in older age and preoperative dry eye disease. In order to prevent post-refractive surgery dry eye, caution should be exercised in middle aged patients with preoperative dry eye disease.

Initial Pattern of Optic Nerve Enhancement in Korean Patients with Unilateral Optic Neuritis

PURPOSE: The purpose of this study was to demonstrate whether the pattern of optic nerve enhancement in magnetic resonance imaging (MRI) can help to differentiate between idiopathic optic neuritis (ON), neuromyelitis optica (NMO), and multiple sclerosis (MS) in unilateral ON. METHODS: An MRI of the brain and orbits was obtained in patients with acute unilateral ON. Patients with ON were divided into three groups: NMO, MS, and idiopathic ON. The length and location of the abnormal optic nerve enhancement were compared for ON eyes with and without NMO or MS. The correlation between the pattern of optic nerve enhancement and the outcome of visual function was analyzed. RESULTS: Of the 36 patients with ON who underwent an MRI within 2 weeks of the onset, 19 were diagnosed with idiopathic ON, 9 with NMO, and 8 with MS. Enhancement of the optic nerve occurred in 21 patients (58.3%) and was limited to the orbital segment in 12 patients. Neither the length nor the location of the optic nerve enhancement was significantly correlated with visual functions other than contrast sensitivity or the diagnosis of idiopathic ON, MS, or NMO. Patients with greater extent of optic nerve sheath enhancement and more posterior segment involvement showed higher contrast sensitivity. CONCLUSIONS: Our data revealed that the pattern of optic nerve enhancement was not associated with diagnosis of idiopathic ON, NMO, or MS in Korean patients with unilateral ON. We believe further studies that include different ethnic groups will lead to a more definitive answer on this subject.

Osteoneogenesis on Subperiosteal Orbital Hematoma in a 10-Year-Old Boy

PURPOSE: We report the first case in Korea of rapid bone formation on a subperiosteal orbital hematoma after trauma. CASE SUMMARY: A 10-year-old boy who was in the intensive care unit after trauma showed proptosis and ocular movement limitation of the right eye associated with subperiosteal hematoma. On ocular examination, 3 mm of proptosis and limitation of right eye movement were observed; however, visual acuity was not decreased. At 1 month after the trauma, orbital computed tomography (CT) showed new bone formation at the margin of the hematoma border although the size of the hematoma decreased. The patient underwent hematoma and bony tissue removal using anterior orbitotomy approach. A new bone was formed between the orbital border and hematoma from the anterior orbital margin to the orbital apex. During pathological examination, woven bone tissue with fibrotic tissue was observed in the hematoma wall. One year after surgery, the patient's proptosis and limitation of ocular movement disappeared without any evidence of new bone formation. CONCLUSIONS: Waiting for spontaneous absorption of orbital subperiosteal hematoma is usually recommended unless there is significant functional impairment. However, as in our case, new bone formation could occur during a short period of less than 1 month; imaging follow-up is necessary in patients having intensive care or showing delayed absorption of a hematoma.