hello and welcome to HCM,
I can understand your concern about the hearing loss
Unfortunately, since at the time of the surgery the surgeon would have been more concerned to reduce the pressure within the brain and also to save your vision, the hearing nerve would not have been intervened much.
Since you have mentioned 8th nerve damaged, i would assume that the vestibulocochlear nerve
which is the eight nerve is damaged. This is the nerve of hearing and balance. This would explain your giddiness and hearing loss. Optic nerve
is the nerve of vision and is the second cranial nerve
As far as giddiness is concerned, this may improve with time. Your hearing loss may however have poor outcome. Nevertheless you can start a steroid like prednisolone
8 mg thrice daily after food in reducing doses along with zincovit once daily after food. Your doctor will know about the same. Also ask for multivitamin
injections to further improve the general nutrition and recovery.
Get and audiometry
done and see if it conductive or sensorineural hearing loss. If it is the former, meet an ENT who can try to salvage some hearing if possible. If it is the latter then you can follow what i Have mentioned above.
hope you recover
Dr Sriram Nathan