An analysis of diagnostic delay in unilateral facial paralysis

Bell's palsy or idiopathic facial palsy is the commonest cause of unilateral lower motor neuron facial palsy. Misdiagnosis of facial nerve palsy as Bell's palsy is still seen in clinical practice. The clinician should always consider the possibility of a potentially serious underlying pathology before making the diagnosis of Bell's palsy. We present a series of 13 patients referred to our ENT department with an initial diagnosis of Bell's palsy. Further clinical examination and investigation revealed the underlying cause. Many had additional symptoms and signs related to the ear. In all patients with unilateral facial palsy a detailed history should be taken and thorough clinical examination carried out. Where no recovery occurs within the expected time period further radiological investigations such as computerized axial tomography (CT) and magnetic resonance imaging (MRI) should be performed. Current scanning techniques provide good quality images, which can show occult lesions of the temporal bone, internal acoustic canal and/or cerebellopontine angle. Radiologists with a special interest and experience in otoneurological radiology should ideally report these images, and a close co-operation between ENT surgeon and radiologist is essential in arriving at a proper diagnosis.