Welch Allyn MicroTymp 3 portable tympanometric instrument - User Manual - Manual (Page 36)

36 Interpreting test results Welch Allyn MicroTymp3 portable tympanometric instrument
Flat tympanograms
Flat tympanogram with normal ear canal volume
Condition which causes a flat tympanogram with normal ear canal volume:
• Middle ear effusion
Flat tympanogram with increased ear canal volume
Conditions which cause flat graph and increased ear canal volume:
• Patent tympanostomy tube
• Perforated tympanic membrane
-400 -200 0 200
2
0.5
0
1.0
1
1.5
PRESSURE - daPa
Ya - mmho
Vea
+200
LEFT EAR
Note This condition may produce a persistent OPEN message if measured Vea is
greater 2.5 cc. See
page 24 .
-400 -200 0 200
2
0.5
0
1.0
1
1.5
PRESSURE - daPa
Ya - mmho
Vea
+200
LEFT EAR