CPT® Code 95933

Electrodiagnostic studies of the blink reflex, also known as the orbicularis oculi reflex, are specialized tests conducted to assess the functionality of the trigeminal cranial nerve (CN V), the facial nerve (CN VII), and the brainstem. This procedure is essential for diagnosing and localizing potential pathologies affecting these neural structures. The blink reflex is a protective mechanism that involves a neural circuit starting from the cornea, where sensory nerve endings are located. When the cornea is stimulated, a nerve impulse is generated and travels through the trigeminal nerve and its ganglion, reaching the spinal trigeminal tract and nucleus. From there, the signal is relayed to interneurons in the reticular formation, which then activate motor neurons in the facial nucleus and nerve, ultimately resulting in a contraction of the orbicularis oculi muscles that causes a blink. During the electrodiagnostic testing, a brief electrical stimulus is applied, typically to the supraorbital nerve, to provoke a blink response. Electrodes are strategically placed on the skin surrounding the eyes to capture the responses elicited by the electrical stimulation. The supraorbital nerve is stimulated using an electrode positioned above each eyebrow, and the resulting responses are recorded and displayed on a computer screen. These recordings are subsequently printed and analyzed by a physician, who provides a comprehensive written interpretation of the test results, aiding in the diagnosis of any underlying conditions affecting the cranial nerves or brainstem.