Ruling Out Paradoxical Vocal Fold Motion/Vocal Cord Dysfunction Lookalikes

You’ve just had a new patient referred to you for assessment of possible paradoxical vocal fold motion/vocal cord dysfunction (PVFM/VCD). Having treated many patients with this disorder and your excellent track record of success with behavioral treatments, you’ve been seeing a lot more referrals from physicians lately, often without prior due diligence on the part of the referring physician.

On the one hand, this speaks well to your track record of successful treatment of upper airway disorders. On the other hand, this uptick in referrals, many of which are inappropriate, has placed you in a tough position.

Each New Patient Is a Puzzle

One of the most intriguing aspects of working with individuals with upper airway disorders is the critical thinking challenge each new referral presents. The most vital aspect of the initial assessment process is determining if the individual actually has PVFM/VCD.

Once the diagnosis of PVFM/VCD is affirmed, the clinician then needs to discern if the condition is co-occuring with other medical conditions that may be part of the differential diagnosis. Examples of this could include laryngeal edema secondary to allergies, laryngeal breathing dystonia, or panic attack.

Other Conditions Mistaken for PVFM/VCD

Competence with differential diagnosis develops over time. After more than 25 years treating PVFM/VCD, I continue to learn about other diagnoses that are often mistaken for PVFM/VCD. While these aren’t the only conditions that could be mistaken for PVFM/VCD, I recently treated two clients who were referred for probable PVFM/VCD but were ultimately diagnosed with mast cell activation syndrome in one case and phrenic nerve dystonia in another.

Mast Cell Activation Syndrome

For my client with mast cell activation syndrome, a disorder of the immune system that may result in anaphylaxis or anaphylaxis-type attacks, the primary symptoms included sudden loss of voice, difficulty with both inhaling and exhaling, and sudden onset of abdominal distension.

This symptom profile is more consistent with laryngeal edema secondary to an allergic response. Having seen prior clients with mastocytosis who also had sudden onset of abdominal distention, I suspected a mast cell dysfunction and referred the individual back to the referring physician with questions regarding possible mast cell involvement in the presenting symptoms.

Phrenic Nerve Dystonia

My client diagnosed with phrenic nerve dystonia presented with persistent, episodic, sudden inspiratory stridor only during waking hours. Careful observation of her breathing behavior and a detailed client interview of her experience and perceptions during the inspiratory events indicated that the presentation was more consistent with a neurological etiology.

The clinical indicator of patterned, involuntary inspirations that resolved during sleep unaccompanied by laryngeal tightness or stridor narrowed down the diagnosis to a phrenic nerve dystonia.

When to Refer Back

If, after careful interview and observation, the presenting symptoms do not clearly indicate PVFM/VCD, we are obligated to refer the patient back to the referring physician for further work-up.

While it is true that the breathing recovery exercises for PVFM/VCD are not harmful and may offer some relief, in neither case described above would a behavioral approach have been helpful. Acknowledging this is part of a skillful clinical assessment. Failure to refer the client on for further assessment in a timely manner may delay diagnosis of the actual etiology and the return of the client’s quality of life.