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"Saw-tooth sign" in upper airway disorders—a case report
Sonu Sahni1, Alexander Blood, Santhosh Paulus
1North Shore - Long Island Jewish Health System, Department of Pulmonary, Critical Care and Sleep Medicine, New York, USA. arunabh@nshs.edu.
Pneumonologia I Alergologia Polska
|March 11, 2015
Summary
Flow oscillations on spirometry, known as the "saw-tooth" sign, indicate upper airway obstruction. Recognizing this pattern on flow-volume loops prompts physicians to investigate potential upper airway pathologies.
Area of Science:
- Pulmonary Medicine
- Respiratory Physiology
Background:
- Spirometry is a key screening tool for obstructive lung diseases.
- Flow oscillations, or the "saw-tooth" sign, on spirometry loops are linked to upper airway obstruction and collapsibility.
- These oscillations are commonly observed in obstructive sleep apnea syndrome but also in other upper airway conditions.
