History-anchored interpretation of discordant JK-05A outputs in Eustachian tube function testing.

PURPOSE: The JK-05A platform performs up to four Eustachian tube (ET) subtests in a single session; however, the outputs often disagree. We evaluated discordant JK-05A outputs in a single-center cohort and developed a practical framework for their interpretation. MATERIALS AND METHODS: We retrospectively analyzed 51 patients who underwent JK-05A testing between September 2025 and April 2026 using explicit reading rules. Inter-test concordance, sonotubometric threshold provenance, and the Japan Otological Society (JOS) criteria informed a history-anchored, functional-domain approach. Patulous ET (PET)-suspected cases were categorized according to the JOS criteria, whereas obstructive dysfunction was described functionally. RESULTS: Outputs were concordant in only a minority: sonotubometry agreed with tubo-tympano-aerodynamic graphy resting synchrony in 52.3%, and only 34.1% of the 44 patients with all four binary signals evaluable were unanimous. Directional sonotubometric patterns demonstrated an ordered distribution: PET was present in 60.0%, 24.0%, and 6.7% of the patulous-leaning, intermediate, and obstructive-leaning patterns, respectively, whereas obstructive ET dysfunction, with or without otitis media, increased from 20.0% to 36.0% to 60.0%, respectively. This ordering is partly circular because the patulous-leaning features are themselves JOS objective signs. CONCLUSIONS: JK-05A is better interpreted as a history-anchored functional profile than as independent diagnostic verdicts. A negative sonotubometric response does not exclude PET, and obstructive dysfunction should be described functionally rather than diagnosed by JK-05A alone. Discordant outputs may reflect differences in functional domains, intermittent physiology, or measurement conditions rather than a single disease category. This internally derived framework requires prospective evaluation with independent readers and control ears.