Y. Ducic et al., DESCRIPTION AND EVALUATION OF THE VALLECULA SIGN - A NEW RADIOLOGIC SIGN IN THE DIAGNOSIS OF ADULT EPIGLOTTITIS, Annals of emergency medicine, 30(1), 1997, pp. 1-6
Study objective: To describe and prospectively evaluate a new radiolog
ic sign with the potential to increase the diagnostic accuracy of soft
-tissue radiography of the neck in the identification of adult epiglot
titis. Methods: We conducted a prospective, before-and-after blinded s
tudy at two tertiary care institutions. A convenience sample of four s
taff emergency physicians, three otolaryngology residents, four radiol
ogy residents, and four senior medical students volunteered to partici
pate. We assembled 26 soft-tissue radiographs of the neck from consecu
tive patients ED with the diagnosis of epiglottitis made on the basis
of direct visualization. Twenty-six control radiographs were identifie
d from ED patients who were being evaluated for the presence of foreig
n bodies or minor cervical trauma. We then randomly mixed the two sets
of radiographs. Participants were asked to identify epiglottitis amon
g the 52 randomly sequenced radiographs. A standardized 5-minute tutor
ial on the vallecula sign was presented to all participants after the
first interpretation. We then asked the participants to make a second
interpretation of the 52 radiographs without knowledge of correct answ
ers from the initial evaluation. Results: The participants accurately
classified 80.5% of all radiographs reviewed before the tutorial and 9
8.8% after the tutorial (P<.0001). Similarly, sensitivity improved fro
m 78.5% to 98.2% (P<.0001) and specificity improved from 82.8% to 99.5
% (P<.0001). We found no significant differences in performance charac
teristics among the different types of participants. Conclusion: We ha
ve described a new radiographic sign that improves the diagnostic accu
racy of soft-tissue radiography of the neck. If reproduced in prospect
ive studies, the absence of the vallecula sign on radiography might ob
viate the need for routine use of direct visualization as an initial s
creen.