Impulse Oscillometry in Idiopathic Subglottic StenosisCap


About this study

The purpose of this study is to describe impulse oscillometry (IOS) in patients with symptomatic idiopathic subglottic stenosis (iSGS). The study will also compare IOS findings in patients with iSGS with IOS findings in patients with small airways obstruction and in healthy controls.


Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria:

  • Age ≥ 18 years
  • For iSGS:
    • Endoscopic confirmation of airway narrowing at or above the cricoid and at or below the larynx
    • Respiratory symptoms, including stridor or dyspnea at rest or with exertion
  • For asthma:
    • Asthma documented by a MC pulmonologist on the basis of compatible symptoms with evidence of fixed or inducible/reversible airways obstruction with or without elevated exhaled nitric oxide (eNO)
    • Evidence of active airflow obstruction based either on a reduction in the patient’s peak expiratory flow (PEF) <80% of personal best or irreversible obstruction on PF testing
  • For healthy volunteers:
    • Absence of chronic cardiopulmonary conditions and respiratory symptoms

Exclusion Criteria:

  • Smoking
  • Restrictive lung disease
  • Diseases known to cause neuromuscular weakness: amyotrophic lateral sclerosis, phrenic nerve injury, frailty
  • MVV<30 times the one-second forced expiratory volume (FEV1) in asthma or healthy controls groups


Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status Contact

Rochester, Minn.

Mayo Clinic principal investigator

Dante Schiavo, M.D.

Open for enrollment

Contact information:

Dante Schiavo M.D.


More information


Publications are currently not available

Study Results Summary

Not yet available

Supplemental Study Information

Not yet available


Mayo Clinic Footer