Our team recently described a new medical condition called HELPS (Hemi-Laryngo-Pharyngeal-Spasm) syndrome(1). HELPS syndrome is a condition caused by a blood vessel pinching the nerve rootlets of the Vagus nerve (Xth cranial nerve). It is similar to the well recognized hemifacial spasm syndrome but the nerve involved is the Vagus instead of the Facial nerve. As a result, the symptoms are episodic throat contractions and cough. The throat contractions become stronger and more frequent over the years and can lead to a terrifying inability to breath. Patients may end up intubated in the Emergency Department or with a tracheostomy because of inability to breath during a severe episode. Some but not all of our patients can tell which side of their throat (left or right) contracts during a choking episode. In between these choking episodes, patients feel normal. A surgical cure for these patients is Microvascular Decompression of the Xth nerve.

The treatment of HELPS syndrome begins with the correct diagnosis. Some patients are able to localize the side of their symptoms in HELPS syndrome while others are unable to. The purpose of this study is to prospectively study which of the following is the diagnostic test of choice for patients who are unable to localize their HELPS: 1. CISS MRI sequences, 2. interictal laryngoscopy, and 3. unilateral and contralateral Botox injections separated 3-months apart.

Both neuroradiologist and otolaryngologist will be blinded to the outcome of surgery and be asked "based on your diagnostic test, which side do you believe we should perform MVD surgery?"

Inclusion Criteria:

• Patients diagnosed with HELPS as described in our initial publication (Honey et al. 2016)
• Patients unable to localize the side of their HELPS syndrome

Exclusion Criteria:

- Unable to provide informed consent

HELPS (Hemi-Laryngo-Pharyngeal Spasm) Syndrome

-Subgroup of patients who are unable to localize lateralization of throat contractions