**Core Concept:** Otitis media is an inflammation of middle ear, which may lead to complications within the skull. Intracranial complications include meningitis, abscess, and cerebrospinal fluid (CSF) leak.

**Why the Correct Answer is Right:**

All the given options (A, B, C, and D) are indeed intracranial complications of otitis media. However, the correct answer (E) is specific to mastoiditis, which is an infection of the mastoid air cells adjacent to the middle ear. Mastoiditis can lead to complications such as mastoid cell abscess and mastoiditis-related intracranial complications.

**Why Each Wrong Option is Incorrect:**

A. Encephalitis - This is a brain inflammation, not a complication of otitis media. Encephalitis is typically caused by viral, bacterial, or other infections or autoimmune reactions unrelated to middle ear infections.

B. Subarachnoid haemorrhage - This is a type of stroke caused by bleeding in the subarachnoid space (the space between the arachnoid and pia mater in the brain). It is not directly related to otitis media complications.

C. Intracranial abscess - An intracranial abscess can occur secondary to spread of infection from adjacent structures like mastoid cell abscess, but it is not a direct complication of otitis media.

D. Subdural haemorrhage - Similar to subarachnoid haemorrhage, this is a type of stroke caused by bleeding between the dura mater and arachnoid mater. It is unrelated to otitis media complications.

E. Mastoiditis - Mastoiditis is a complication specific to the mastoid air cells adjacent to the middle ear, which can lead to complications like mastoid cell abscess and intracranial complications.

**Clinical Pearl:** Otitis media, particularly when not managed promptly, can lead to serious complications involving the skull base and intracranial structures. Prompt diagnosis and treatment are vital to prevent these complications.