Certified Neuroscience Registered Nurse (CNRN) Practice Exam

What is the most important diagnostic test for a patient with a dull headache, ice pick sensations on the scalp, jaw claudication, and elevated ESR?

1. Magnetic Resonance Imaging (MRI)

2. Computed Tomography (CT) scan

3. Temporal artery biopsy

4. Electromyography (EMG)

The correct answer is: Temporal artery biopsy

In the context of the symptoms described—dull headache, ice pick sensations on the scalp, jaw claudication, and elevated ESR—the most important diagnostic test is a temporal artery biopsy. This test is specifically used to diagnose giant cell arteritis (GCA), which is a form of vasculitis that commonly presents with the symptoms noted. The presence of jaw claudication and scalp pain, in conjunction with an elevated ESR, suggests inflammation of the temporal artery, which can lead to serious complications if not diagnosed and treated promptly. A temporal artery biopsy allows for the direct examination of the arterial wall and can confirm the diagnosis by showing the characteristic findings of necrotizing arteritis associated with GCA. Other diagnostic tests, such as MRI or CT scans, may be useful in ruling out other causes of headaches or brain pathology but do not provide the specific insight into the condition affecting the temporal arteries like a biopsy does. Electromyography (EMG), while helpful in evaluating neuromuscular disorders, is not relevant in this scenario as it does not pertain to vasculitis or headaches. Thus, the temporal artery biopsy stands out as the critical diagnostic procedure in confirming the presence of giant cell arteritis in this clinical context.