Diagnosis of internal carotid artery stenosis in a patient referred to a physiotherapist for dizziness

PURPOSE: The purpose of this report is to describe the diagnostic focus of the clinical decision-making process for a patient referred to a physiotherapist for treatment of persistent dizziness, who was subsequently diagnosed with severe stenosis of the internal carotid arteries. CASE DESCRIPTION: The patient was a 79-year-old man who was referred to a physiotherapist by his primary care physician for the treatment of persistent intermittent dizziness. The patient's dizziness began 6 months prior insidiously*it was worsening over time and now interfered with activities of daily living. The patient denied cervical pain or headaches, numbness or tingling in his extremities, difficulty maintaining balance with walking, unsteadiness, muscle weakness, dysphagia, drop attacks, diplopia or dysarthria. At the physiotherapist's initial evaluation, cervical range of motion was moderately restricted in all motions and his dizziness was elicited with changes in head position. The patient's neurological examination was unremarkable. Due to positional complaints of dizziness, a Dix-Hallpike test was used to screen for benign paroxysmal positional vertigo, which was positive for symptoms reproduction*however, no nystagmus was noted. The patient also became diaphoretic and exhibited significant discoloration of his face during the test. OUTCOMES: Due to concern over vascular compromise, carotid duplex ultrasonography and magnetic resonance angiography were completed and revealed near complete occlusion of the left internal carotid artery at its origin. The patient subsequently underwent a left internal carotid endarterectomy with resolution of symptoms and a return to all activities of daily living. DISCUSSION: Carotid artery stenosis, although frequently asymptomatic until severe, may manifest as complaints of dizziness that mimic peripheral vestibular dysfunction. Appropriate and prudent screening and referral is necessary if clinical symptoms suggestive of vascular compromise are present.