What causes numbness on the left side of my face?

Friends who have numbness on the left side of their face should pay attention to check and understand the cause so that symptomatic treatment can be given. The most common causes are tear gland secretion disorders, changes in the eyeballs, and symptoms of auditory hypersensitivity. Only after understanding these causes can effective treatment be given.

1. Lacrimal gland secretion disorder

When facial nerve paralysis occurs, salivary gland and tear gland secretion dysfunction, forehead wrinkles become shallower or disappear, and inability to frown is an important clinical feature of Bell's facial nerve palsy. The bilateral nasolabial grooves become shallower, the lips cannot be closed tightly, water leaks from the corners of the mouth, and food remains in the cheeks when eating. Therefore, for patients with facial nerve paralysis, liquid and semi-liquid foods should be the main diet.

2. Eye changes

The eyeball of patients with facial nerve paralysis is not at the same level as the healthy side, but is moved upward compared to the healthy side, and the pupil level is also higher than the healthy side. This sign is called the eyeball sign.

3. Symptoms of hyperacusis.

After many cases of facial nerve paralysis occur, patients will experience hyperacusis. This is mainly because when the facial nerve is paralyzed, the stapedius muscle is paralyzed. As a result, the tensor tympani muscle is relatively tense, the tension of the tympanic membrane is high, and small sounds produce strong vibrations, resulting in overhearing. The tensor tympani muscle that keeps the tympanic membrane tense is innervated by the medial pterygoid nerve, which is a branch of the trigeminal nerve, and the stapedius muscle is innervated by the facial nerve. These two muscles are in an antagonistic relationship to maintain balance.

4. Involvement of the geniculate ganglion

In addition to auditory hypersensitivity, taste disturbance in the anterior 2/3 of the tongue on the same side, and peripheral facial nerve paralysis, there is also pain in the mastoid area of ​​the affected side, decreased sensation in the auricle and external auditory canal, herpes in the external auditory canal or tympanic membrane, the eyeball on the paralyzed side is not at the same level as the healthy side, but is moved upward compared to the healthy side, and the pupil level is also higher than that of the healthy side.