SESSION TITLE: Miscellaneous Case Report Posters III
SESSION TYPE: Affiliate Case Report Poster
PRESENTED ON: Tuesday, October 28, 2014 at 01:30 PM - 02:30 PM
INTRODUCTION: Vocal cord dysfunction (VCD) is a condition characterized by paradoxical adduction of vocal cords. VCD can be inspiratory, expiratory or a combination of both. (1)
CASE PRESENTATION: A 60-year-old female with a history of multiple intubations presented for evaluation of a “difficult-to-control asthma”. Physical examination was within normal limits apart from chest auscultation that revealed evidence of high-pitched inspiratory wheeze transmitted from the upper airways. Spirometric parameters revealed an Empey’s index [FEV1 (ml) / PEF (L / m)] of 16.1 consistent with an upper airway obstruction (UAO). Flow volume loops (FVL) showed flattening of both inspiratory and expiratory curves (suggestive of a fixed UAO) (Fig.1-A). The ratio between maximum expiratory and inspiratory flows at 50% of forced vital capacity (FEF 50/FIF 50) was 1.5 (suggestive of a variable extra-thoracic UAO). The patient underwent fiberoptic bronchoscopy that showed normal airways with no evidence of stenosis or tracheomalacia. Vocal cords were free of lesions but showed abnormal adduction with an open posterior glottic chink through the respiratory cycle, with more adduction during inspiratory phase, consistent with inspiratory and expiratory VCD (Fig.1-B,C). Patient was referred to speech therapy.
DISCUSSION: Fixed UAO is characterized by flattening of both inspiratory and expiratory curves of FVL with FEF50/FIF50=1. Variable extra-thoracic UAO is characterized by flattening of inspiratory curve of FVL with FEF50/FIF50>1.(1) Our patient had a mixed combination of morphological and quantitative diagnostic criteria of FVL and spirometric parameters respectively due to the combined nature of her VCD. It is important to recognize the three types of vocal cord dysfunction. The phasic nature of the dysfunction can mimic other pathologies. Preserved posterior glottis chink is essential for differentiating true VCD from adduction of vocal cords provoked by gag reflex upon insertion of the scope into the upper airway. In absence of symptoms, the vocal cord adduction may not be seen, thus a normal examination does not exclude the diagnosis.(2)
CONCLUSIONS: It is essential to consider vocal cord dysfunction in every case of presumed refractory asthma. Both the morphology of flow volume loops and spirometric parameters are useful diagnostic tools.
Reference #1: Goldman J, Muers M.Vocal cord dysfunction and wheezing.Thorax. 1991 Jun;46(6):401-4.
Reference #2: Wood RP 2nd, Milgrom H.Vocal cord dysfunction. J Allergy Clin Immunol.1996 Sep; 98(3):481-5.
DISCLOSURE: The following authors have nothing to disclose: Karim El-Kersh, Umair Gauhar, Rodrigo Cavallazzi, Rafael Perez
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