Usually sudden hearing loss are idiopathic.
Don't worry..
Intra tympanic steroid injections are still under trial, it gives a little improvement, but not remarkably.
Continue the steroid inj to complete 8 doses and if possible start on oral steroids, after getting rbs and consulting your doctor.
For vertigo, start on tab vertin 16mg tid, tab stugeron 25mg in night with tab pan 40 morning bf, for a week. Add on tab absolut 3G.
Next Steps
get hearing test on the next visit to look for improvement with steroids.