Causes. The exact cause of optic neuritis is unknown. However, optic neuritis is believed to develop when the immune system mistakenly targets the substance covering your optic nerve (myelin), resulting in inflammation and damage to the myelin.he following autoimmune conditions often are associated with optic neuritis: Multiple sclerosis. Multiple sclerosis is a disease in which your autoimmune system attacks the myelin sheath covering nerve fibers in your brain and spinal cord.
See how you can use online check-in (see below) to print your boarding passes from home any time within 24 hours of your flight. And at certain airports, you can go completely paperless by having an eBoarding Pass delivered to your mobile device. Check In Now. How to Use Online Check-in.
Best Answer: Chances are you have purchased an E-ticket. Even though you may have a reservation you won't be able to print your return boarding pass until 24 hours prior to the flight departure. However, if you go on the airline website you may be able to get your seat assignment at this time.Source(s): Flight attendant for a major airline.o the boarding pass is only for the current outbound flight. You have to check in again for your return flight, and at that time will receive another boarding pass. ctelly22 Â· 8 years ago. Thumbs up.