I'd be looking into Panophthalmitis, an infection of tisue under the spectacle. It's thought that damp or cold cage conditions or hygiene problems are the cause, but it usually follows canker. Canker causes a blockage of the lacrymal duct (which leads from the roof of the mouth to the eye. If she hasn't had canker (properly known as stomatitis - mouth rot) then the cold/damp conditions may cause mucous build-up in the lacrymal duct, also causing infection and blockage. The affected eye(s) can have a swollen or rough appearance or look cloudy outside of shedding time. In bad or progressive cases the eye can become bloodshot and badly swollen. In the one case I heard of the snake had to be taken to the vet and the eye removed, so it's best to jump on it and take her to a vet.