Evaluation of olfactory loss

Head injury

Every effort must be made to discover the underlying cause of the injury.

Patients must be assessed for other injuries and their level of consciousness determined. Mechanical ventilation may be required if the patient is unconscious. Depending on the level of consciousness and severity of injury, patients will require a skull x-ray, computed tomography (CT), or magnetic resonance imaging (MRI) scan.

Pupillary inequalities or abnormal light reflexes indicate intracranial hemorrhage. Headache, nausea, vomiting, falling pulse rate, and rising blood pressure indicate cerebral edema.

Nasal examination will be normal unless there are other sequelae from the injury. Findings of nasal trauma (such as fracture deviation of the nasal dorsum and a displaced septum) may indicate direct injury to the olfactory cleft, or may still be consistent with a coup-contrecoup injury, or may have led to secondary nasal and sinus pathology causing a conductive olfactory loss.

Nasal malignancies

Anosmia, nasal obstruction, or epistaxis together with unexplained headache, change in vision or motor function, poor coordination, and ataxia are suggestive of nasal tumors.

Nasal biopsy and histopathology can be used to identify malignant tumors such as squamous cell carcinoma, adenocarcinoma, esthesioneuroblastoma, melanoma, and sinonasal undifferentiated carcinoma (SNUC), and benign tumors such as inverted papilloma, schwannoma, and capillary hemangioma.

For sinonasal tumors, a CT scan of the paranasal sinuses will show a mass lesion generally with surrounding areas of bone erosion. An MRI scan of the head will help differentiate the tumor from brain and other normal structures.

For esthesioneuroblastoma, a CT scan of the paranasal sinuses in the coronal plane will demonstrate a soft tissue mass within the nasal vault, with or without surrounding bone erosion, and possibly with secondarily obstructed sinus cavities. An MRI scan of the head will help delineate intraorbital or intracranial extension.

For olfactory groove meningioma, a CT scan of the head with contrast will show extradural, homogeneously enhancing mass bluntly displacing the brain, and possible skull base erosion.