Olfactory nerve damage

Outlined the real olfactory nerve is very short, so far there is no primary olfactory neuropathy, Chang and other cranial nerve disease with the presence or secondary to other diseases, the main symptoms of olfactory dysfunction. Cause pathogenesis of the main olfactory fiber conduction blockage. Common causes of intracranial hematoma, the anterior cranial fossa, saddle area and parasellar tumors, trauma, intracranial hypertension patients with hydrocephalus, Senile olfactory nerve atrophy, various poisoning and infection. Certain temporal lobe epilepsy and mental illness. Clinical manifestations of olfactory nerve damage to the main performance smell dissipated, deletion, and olfactory hallucinations olfactory allergy. A differential diagnosis, smell diminishes, deletion (1) certain the infection and chronic rhinitis caused by the smell they often diminish both the nose and nasal inflammation Cavity obstruction, partial checks have nasal congestion, turbinate hypertrophy. (2) of skull base tumors (tumor of the bast of the skull) olfactory meningioma the most common, patients with chronic headache often mental disorders. Olfactory nerve compression due to the side or both sides have lost their sense of smell. With the growth of tumors produce symptoms of intracranial hypertension, brain CT in the diagnosis can often be clear. (3) some of the central nervous system associated with Alzheimer's disease (Alzheimer's disease, Korsakoff psychosis, hereditary chorea, etc.) can cause olfactory nerve atrophy bilateral smell dissipated. Such patients commonly found in elderly patients, with positive family history. Brain CT, MRI and other common brain atrophy. (4) traumatic brain injury (craniocerebral injury) Anterior skull fracture and frontal bottom The brain contusion and hematoma, can cause olfactory nerve tear and oppression caused loss of the sense of smell, according to a clear history of trauma. skull X-ray, CT diagnosis can be made. 2. olfactory hallucinations (1) temporal lobe epilepsy (temporal lobe epilepsy) temporal lobe epilepsy clinical is varied, hooked to attack performance olfactory hallucinations and dream-like state, Patients can smell an unpleasant smell like rotten bad food, corpses, charred goods, chemical odor, EEG examination showed focal abnormal temporal lobe wave. (2) schizophrenia (schizophrenia) in some patients with schizophrenia. olfactory hallucinations as a symptom or other hallucination and paranoia combine performance, and psychiatric examination can be more clear diagnosis