A 70-year-old male presents with loss of sensation in external auditory meatus (Hitselberger sign positive). The likely diagnosis is:

(a) Vestibular schwannoma(Ref. Shambaugh, 6th ed., 647)In vestibular schwannoma the involvement of sensory fibres of facial (i.e. nervus intermedius or nerve of Wrisberg) leads to anaesthesia over the postero-superior part of external auditory meatus and canal. This is known as 'Hitselberger sign'. But this 'Hitselberger sign' is present only in 25% of patients.Mastoiditis shows "reservoir sign".Bell's palsy is acute idiopathic lower motor neuron palsy of facial nerve.Cholesteatoma is the presence of keratinising stratified squamous epithelium in any part of temporal bone where it is not usually present.