No, it is not possible for you to lead to astigmatism from watching tv because astigmatism could be caused by the born-to-be at the eyes pupils. The TV screen will transmit the radiation to your eyes which could cause your eyes to be myopia. You should watch tv within less time and have rest now and then to give the rest for the eyes.
Yes, watching TV can lead to astigmatism. If you watch TV in a short distance, or watch TV while lying on bed with your head tilting to one side, it's likely to lead to astigmatism. And if the TV screen is very big, it's more likely to lead to astigmatism. To avoid astigmatism, you should not watch TV too long, rub your eyes, or lying on bed while reading or watching TV and especially use your cellphone at night.
I am a person who has got the symptom of astigmatism, the mean of this eye disease is refer to the inconsistent of refractive power of the eyes in different longitudes, or the diopter range different in the same longitudes. From the ophthalmology, we can find it is a symptom which impaired eyesight resulting usually from irregular conformation of the cornea. It is also a defect in an optical system in which light rays from a single point fail to converge in a single focal point. The astigmatism is usually caused by the incorrect posture of watching. But watching TV for a long time will lead to the fatigue of eyes, it will get dry eye, tears, eye swollen, sore eye or blur vision symptom later if you are not pay attention to this situation of long time eyes use of watching TV. The screenshot are too dazzling to people, it hurt the visual purple to makes color cast and hurt the visual pigments and hurt ciliaris for a long time, then lead to myopia. You'd better take care of your eyes, binding the time of TV watching and make sure the TV in modest rays' condition.