48 Neurological conditions: Bell palsy, and trigeminal sensory loss
Box 48.1 Causes of orofacial sensory loss.
Trauma (facial or dental)
Connective tissue diseases
Sickle cell anemia
Definition: An acute lower motor neurone paralysis (palsy) of the face, representing about 50% of all facial palsies (Table 48.1).
Prevalence (approximate): 1 per 10,000.
Age mainly affected: Young adult.
Gender mainly affected: M = F.
Etiopathogenesis: No local or systemic cause can be identified in Bell palsy (it is idiopathic). There is pressure from inflammation and edema on the facial nerve, usually in the stylomastoid canal, with demyelination. Similar lesions are associated:
- Usually with herpes simplex virus (HSV).
- Rarely with another viral infection such as another herpesvirus/>