Up to 1 in 3 people with cavernous sinus thrombosis may die. Some people who survive it are left with ongoing symptoms such as seizures (fits) and severe headaches.
It can also cause further problems with vision, blood clots and infections.
Problems with vision are a relatively common complication of cavernous sinus thrombosis.
A few people have a degree of permanent visual impairment, although permanent blindness is uncommon.
There's also a risk that another blood clot may develop elsewhere in the body – for example, in the:
These conditions are very serious and can be fatal.
Complications can also occur if the infection spreads beyond the cavernous sinuses. These complications can include:
Both of these conditions are very serious and can be fatal, particularly if they're not treated promptly.