Thank you for posting your query.
The olfactory hallucinations/or foul odour are related either to the tumor
or the injury
to olfactory nerve
system during the surgery.
Spontaneous improvement does occur in some cases over a period of time.
In some cases, anti-epileptic drugs may be useful. Please discuss this with your neurologist
Dr Sudhir Kumar MD DM (Neurology)
Senior Consultant Neurologist