Ann Otol 88 :1979
EUSTACHIAN TUBE FUNCTION AND TYMPANOPLASTY ARNOLD M. COHN, MD
MITCHELL K. SCHWABER, MD
DETROIT, MICHIGAN
HOUSTON, TEXAS
LOIS S. ANTHONY, MA
JAMES F. JERGER, PhD HOUSTON, TEXAS
Despite the reduction in incidence of acute suppurative otitis media since the introduction of antibiotics, the incidence of chronic middle ear effusion and chronic otitis media have not experienced a similar reduction. Eustachian tube dysfunction is believed to be a principal etiological factor in these cases. The inflation-deflation technique to measure tubal function has shown promise in a number of laboratories, and is the basis for our present studies. Traditional application of this technique has been to document the capability of patients with chronic otitis media to equilibrate an induced positive or negative pressure. These patients are compared to a control group of patients with recent traumatic perforation, negative otologic histories, and normal tympanograms in the uninvolved ear. We have applied this test to observe its relationship to successful take of a tympanic membrane graft. The overall pattern of our results suggests that the capability to reduce an induced negative pressure is most frequently associated with successful tympanic membrane closure. However, compromise or even total failure to reduce an induced negative pressure does not preclude successful grafting of the tympanic membrane; nor should such failure to reduce negative pressure by this technique serve as a contraindication to surgery. Our results do suggest that during induced positive pressure application. spontaneous opening of the eustachian tube at opening pressures below +150 mm H 20 may be discriminatory between success and failure.
Renewed interest in the physiology and pathophysiology of the eustachian tube has been stimulated by the persistent incidence of middle ear effusion and chronic otitis media. and the sophistication in current middle ear reconstructive surgery. Several sets of data have been presented to support the premise that the pathogenesis of middle ear disorders involves two mechanisms; 1) a mechanism inducing negative middle ear pressure.v" and 2) pathophvsiologic changes associated with an inflammatory mucosa.t" Tubal dysfunction, whether morphological or functional in cause, may induce both an increase in secretory activity and concurrent hydrostatic transudation, The variabilitv with which these effects are manifested, influences and alters the composition and characteristics of the effusion. Similarly, mucociliary activity may be comnromised, causing further retention of fluid. In-
flammatorv changes in the tissues surrounding the tube may alter its compliance and facilitate what has been caned "locking" mechanisms.P?" The inflation-deflation test originaIIy described by Flisberg et aP6 measures the capability of the eustachian tube to equilibrate an induced negative or positive pressure in the middle ear by deglutition. Of fundamental interest is the degree to which this test of tubal ventilatory function furnishes an objective basis for predicting success of a tympanic membrane graft take in tympanoplasty. This report reviews our experience with the inflation-deflation test for evaluating: the ventilatory function of the eustachian tube. METHODS AND MATERIALS
Equipment. The motorized pump-manometer section of an electroacoustic impedance bridge (Madsen, Z072) was utilized for the study. The system comprised a motorized air pump and an electromanometer scaled ± 400
Fr,?m the Department of Otorhinolaryngology and Communicative Sciences Baylor College of Mediclne, Houston, Texas. • Presented at the Association for Research In Otolaryngology, St. Petersburg Florida .January 30 - February 2, 1978. ' ,
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Downloaded from aor.sagepub.com at Bobst Library, New York University on May 24, 2015
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mm H20; pressures above or below ambient pressure could be applied to the ear under investigation. An outlet at the rear of the bridge allowed connection to an X-Y recorder (Madsen M501). Testing Procedure. All examinations were performed by the same tester on patients in the sitting position. The instrument probe-tip was inserted into the external auditory canal and an airtight seal established. First, a negative pressure was created to a maximum of -200 mm H 20, and an attempt to equilibrate this pressure was encouraged by open-nose swallowing. The residual negative pressure beyond which no further equilibration could be affected by swallowing was recorded. The strip recording also allowed quantitating the pressure drop per swallow. Next, a positive pressure was created to a maximum of +200 mm H20. Occasionally the eustachian tube opened passively before a pressure of + 200 mm H 20 could be reached and the pressure in the system fell until the eustachian tube closed again. If the pressure following passive opening of the tube did not reach zero, or a + 200 mm H 2 0 could be maintained, reduction of this positive pressure was attempted by giving the patient water to sip and the instruction to swallow with an open nose. The residual pressure beyond which no further decrease in pressure could be affected by swallowing was recorded. Eustachian tube function was categorized according to the following criteria: the capability to equilibrate - 200 mm H20 to from o to - 40 mm H20 residual pressure by repeated deglutition was considered normal. The capability to partially equilibrate a negative pressnre of -200 mm H 20, but havlnrr a residnal pressure of from -41 to -100 mm H 20. was considered to have mild tubal dysfunction. A residual negative pressure of more than -100 mm H,O was considered poor tubal dysfunction; these ears were divided into two snhgro1lps. Tn one Sl1h
EUSTACHIAN TUBE FUNCTION AND TYMPANOPLASTY ARNOLD M. COHN, MD
MITCHELL K. SCHWABER, MD
DETROIT, MICHIGAN
HOUSTON, TEXAS
LOIS S. ANTHONY, MA
JAMES F. JERGER, PhD HOUSTON, TEXAS
Despite the reduction in incidence of acute suppurative otitis media since the introduction of antibiotics, the incidence of chronic middle ear effusion and chronic otitis media have not experienced a similar reduction. Eustachian tube dysfunction is believed to be a principal etiological factor in these cases. The inflation-deflation technique to measure tubal function has shown promise in a number of laboratories, and is the basis for our present studies. Traditional application of this technique has been to document the capability of patients with chronic otitis media to equilibrate an induced positive or negative pressure. These patients are compared to a control group of patients with recent traumatic perforation, negative otologic histories, and normal tympanograms in the uninvolved ear. We have applied this test to observe its relationship to successful take of a tympanic membrane graft. The overall pattern of our results suggests that the capability to reduce an induced negative pressure is most frequently associated with successful tympanic membrane closure. However, compromise or even total failure to reduce an induced negative pressure does not preclude successful grafting of the tympanic membrane; nor should such failure to reduce negative pressure by this technique serve as a contraindication to surgery. Our results do suggest that during induced positive pressure application. spontaneous opening of the eustachian tube at opening pressures below +150 mm H 20 may be discriminatory between success and failure.
Renewed interest in the physiology and pathophysiology of the eustachian tube has been stimulated by the persistent incidence of middle ear effusion and chronic otitis media. and the sophistication in current middle ear reconstructive surgery. Several sets of data have been presented to support the premise that the pathogenesis of middle ear disorders involves two mechanisms; 1) a mechanism inducing negative middle ear pressure.v" and 2) pathophvsiologic changes associated with an inflammatory mucosa.t" Tubal dysfunction, whether morphological or functional in cause, may induce both an increase in secretory activity and concurrent hydrostatic transudation, The variabilitv with which these effects are manifested, influences and alters the composition and characteristics of the effusion. Similarly, mucociliary activity may be comnromised, causing further retention of fluid. In-
flammatorv changes in the tissues surrounding the tube may alter its compliance and facilitate what has been caned "locking" mechanisms.P?" The inflation-deflation test originaIIy described by Flisberg et aP6 measures the capability of the eustachian tube to equilibrate an induced negative or positive pressure in the middle ear by deglutition. Of fundamental interest is the degree to which this test of tubal ventilatory function furnishes an objective basis for predicting success of a tympanic membrane graft take in tympanoplasty. This report reviews our experience with the inflation-deflation test for evaluating: the ventilatory function of the eustachian tube. METHODS AND MATERIALS
Equipment. The motorized pump-manometer section of an electroacoustic impedance bridge (Madsen, Z072) was utilized for the study. The system comprised a motorized air pump and an electromanometer scaled ± 400
Fr,?m the Department of Otorhinolaryngology and Communicative Sciences Baylor College of Mediclne, Houston, Texas. • Presented at the Association for Research In Otolaryngology, St. Petersburg Florida .January 30 - February 2, 1978. ' ,
339
Downloaded from aor.sagepub.com at Bobst Library, New York University on May 24, 2015
340
COHN ET AL
mm H20; pressures above or below ambient pressure could be applied to the ear under investigation. An outlet at the rear of the bridge allowed connection to an X-Y recorder (Madsen M501). Testing Procedure. All examinations were performed by the same tester on patients in the sitting position. The instrument probe-tip was inserted into the external auditory canal and an airtight seal established. First, a negative pressure was created to a maximum of -200 mm H 20, and an attempt to equilibrate this pressure was encouraged by open-nose swallowing. The residual negative pressure beyond which no further equilibration could be affected by swallowing was recorded. The strip recording also allowed quantitating the pressure drop per swallow. Next, a positive pressure was created to a maximum of +200 mm H20. Occasionally the eustachian tube opened passively before a pressure of + 200 mm H 20 could be reached and the pressure in the system fell until the eustachian tube closed again. If the pressure following passive opening of the tube did not reach zero, or a + 200 mm H 2 0 could be maintained, reduction of this positive pressure was attempted by giving the patient water to sip and the instruction to swallow with an open nose. The residual pressure beyond which no further decrease in pressure could be affected by swallowing was recorded. Eustachian tube function was categorized according to the following criteria: the capability to equilibrate - 200 mm H20 to from o to - 40 mm H20 residual pressure by repeated deglutition was considered normal. The capability to partially equilibrate a negative pressnre of -200 mm H 20, but havlnrr a residnal pressure of from -41 to -100 mm H 20. was considered to have mild tubal dysfunction. A residual negative pressure of more than -100 mm H,O was considered poor tubal dysfunction; these ears were divided into two snhgro1lps. Tn one Sl1h
