Objective
To investigate the clinical usefulness of scintigraphy for the evaluation of dysphagia in patients with brain lesion and to clarify the most useful quantitative parameter for detection of aspiration using scintigraphy.

Method
For 42 patients with dysphagia, swallowing evaluations were done by videofluoroscopy and scintigraphy. According to videofluoroscopic findings these patients were grouped into three; aspiration, laryngeal penetration and no penetration group. Quantitative parameters from scintigraphy were measured and compared among three patients groups and normal control; these parameters were oral discharge time (ODT), pharyngeal transit time (PTT), oral residue (OR), pharyngeal residue (PR), pharyngeal swallowing efficiency (PSE) and oro-pharyngeal swallowing efficiency (OPSE). Sensitivity and specificity of these parameters detecting aspiration were also evaluated according to the videofluoroscopic findings.

Results
In aspiration group ODT, PTT, PSE and OPSE were 1.18⁑1.14 sec, 1.80⁑1.49 sec, 86.05⁑61.42%/sec and 38.21⁑28.65%/sec respectively, all of which were significantly different from the other groups, but OR and PR were not different statistically. According to the ROC (Relative Operating Characteristic) table, sensitivity and specificity of OPSE were 72.7 and 80.7% respectively, which were the highest among the parameters.

Conclusion
Scintigraphy was useful to quantitative dysphagia in patients with brain lesion. Sensitivity and specificity of swallowing efficiency was higher than time and residue parameters. OPSE was considered to be the most useful quantitative parameter for detecting aspiration.