In Dracula (1992), in the scenes in the asylum where Renfield is being held, the guards can be seen wearing cages on their heads. Why? Was this a normal practice? I have heard of head cages for inmates but not guards. I'm not sure what the purpose would have been other than protection, but give the rest of their body is unprotected there has to be more to it. I've included the best image I could find. If I can get a better one I will update.
The implication is that the inmates are potentially violent and presumably the biggest danger from unarmed but psychotic patients is biting/scratching/gouging at the face and eyes.
Clearly the protection is deliberately crude and underlines the primitive and brutal conditions in that setting in a way that more refined protection might not.
You could also speculate that the head cages reflect the appearance of the barred cells and by placing them on the guard's heads it is a metaphor for the idea that the inmates are prisoners of their own madness.
Equally by obscuring the guards faces with a crude and claustrophobic cage they are somewhat dehumanised and more like automata than medical staff. Indeed the whole visual style of the film uses a lot of elements which evoke stylized dreamlike of hallucinogenic states which confuse individual sense of identity and many of the characters are driven by some sort of obsession and it is implied that Dr Seward is as much a prisoner of his work as the peopel he treats (or at least studies).