1. Why do auditory neuromas present with many symptoms? Auditory neuromas are initially located in the internal auditory canal, compressing the vestibular and cochlear nerves, causing tinnitus and hearing loss. It then gradually protrudes into the brain pool in the pontocerebellar horn region, covered by the arachnoid membrane, and compresses the facial nerve, trigeminal nerve, brainstem (causing obstructive hydrocephalus and increased intracranial pressure), cerebellum and posterior group of cranial nerves, causing compression symptoms in the corresponding areas. 2. How to stage auditory neuroma according to the severity? (1) According to the development of tumor, it is divided into 6 stages: ① the tumor in the inner ear canal is confined to the inner auditory canal ② stage I protrudes into the pontocerebellar horn within 1cm ③ stage II protrudes into the pontocerebellar horn within 2cm ④ stage III protrudes into the pontocerebellar horn within 3cm ⑤ stage IV protrudes into the pontocerebellar horn within 4cm ⑥ stage V protrudes into the pontocerebellar horn above 4cm. According to the above stage, the tumor mainly shows otologic symptoms, such as tinnitus, hearing loss and vertigo, within stage II. In stage III, neurological symptoms appear, including trigeminal, facial and posterior group cerebral nerve symptoms, cerebellar and brainstem symptoms. The symptoms worsen into stage IV and develop significant obstructive hydrocephalus and increased intracranial pressure. Stage V vision loss or even blindness, and death may occur at any time. (2) According to the clinical manifestations, it can be divided into 3 stages ①Stage I tumor is confined to the internal auditory canal, with hearing loss, tinnitus, vertigo and nystagmus and other auditory nerve involvement manifestations. In stage Ⅱ, the tumor enters the brain pool, and the above symptoms are aggravated and vestibular ataxia, headache and dullness of facial and corneal sensation appear. (3) Stage III tumor compresses the brainstem, the above symptoms are aggravated and manifestations of facial nerve and posterior group of cranial nerve involvement such as diplopia, vision loss, headache and increased intracranial pressure are seen, often with obvious cerebellar symptoms.