Eustachian tube function in adults without middle ear disease.

OBJECTIVES: We sought to develop normative values for 5 eustachian tube function (ETF) test protocols in adults without otitis media (OM). METHODS: Twenty adults (19 to 48 years of age) without a recent history of OM (5 had OM in childhood) underwent unilateral myringotomy and were evaluated for ETF by use of the forced response, inflation, deflation, forcible "sniff", and Valsalva test protocols. When possible, these tests were repeated on a second day. RESULTS: Normative values for the parameters of these protocols in adult subjects without a recent history of OM were developed. Between-day data for the forced response test were highly correlated. A percentage of these tests showed eustachian tube "constriction" during swallowing--an abnormal condition. The percent reduction in applied pressures for the inflation and deflation tests was high, indicative of good ETF. Few subjects had a positive "sniff" test, whereas most had a positive Valsalva test, and the results for both tests were effort-dependent. CONCLUSIONS: Results of ETF tests in adults with and without recent OM have not been published. Normative data are now available for comparison with ETF test results in adults with OM. These protocols will be used to evaluate the efficacy of surgical procedures designed to improve ETF.

Balance and otitis media with effusion.

Dizziness can be caused by a variety of peripheral vestibular, central, and systemic disease processes. Eustachian tube dysfunction with and without middle-ear effusion has been considered one of the most common causes of balance disturbances in young children. Several studies have indicated that during an episode of otitis media the child's balance deteriorates and the child may become clumsy and fall more often. Thus, not only the adverse effect on hearing should be considered in the management of a child with otitis media, but also the child's balance.

An unusual solitary endobronchial pulmonary arteriovenous malformation in a 10 year-old child.

Pulmonary arteriovenous malformations (PAVMs) are relatively rare in children. They may occur both as single isolated anomalies and, much more commonly, as one of many widely distributed arteriovenous malformations (AVMs) in other organs and anatomic locations such as the liver, brain, nose and spine. The latter phenotypically defines the condition known as Hemorrhagic Hereditary Telengiectasia (HHT). We report a case of a 10 year-old female with an isolated endobronchial right lower lobe PAVM. The patient's chest radiograph and fine-cut contrast-enhanced CT (CECT) of the neck and thorax were both uncharacteristically normal and, hence, non-diagnostic. Surgical lobectomy was the only means by which to both diagnose and treat this life-threatening condition. This unique case points out the dilemma facing the physician in such a case with only two management options neither of which is ideal: to either obtain a diagnosis with biopsy which is minimally invasive yet life-threatening due to the potential for fatal hemorrhage, or to perform a pulmonary lobectomy which entails removal of an entire lobe of the lung without a pre-operatively confirmed indication to justify the procedure. To our knowledge, this is the first reported case of a child with an endobronchial PAVM who did not carry the diagnosis of HHT, had normal chest radiography, and had a normal fine-cut CECT of the neck and thorax where such a management dilemma arose. This case points out that a high index of suspicion for PAVMs must be maintained despite normal chest radiography and CECT of the chest. In such cases, empiric lobectomy becomes the sole therapeutic and definitive diagnostic intervention. We hope that such a case published in the literature serves as a guide to physicians confronting similar circumstances as the rarity of such a constellation of variables precludes higher levels of evidence reporting such as a retrospective case series or prospective randomized controlled clinical trials.

Role of the mastoid in middle ear pressure regulation.

OBJECTIVES/HYPOTHESIS: Determine the role of mastoid volume in middle ear pressure (MEP) regulation. The hypothesis was that inert gas exchange between blood and middle ear (ME) is slower for larger mastoid volumes. STUDY DESIGN: Prospective. METHODS: For 21 enrolled subjects, the bilateral surface areas and volumes of the mastoid and tympanum were measured from computed tomography scans in 20 subjects with a wide range of mastoid volumes. Then, 19 subjects were reclined in a chair, fitted with a non-rebreathing mask and breathed room air for 20 minutes (acclimation), a gas composition of 25% N(2)O, 20% O(2), balance N(2) for 30 minutes (experiment), and room air for 30 minutes (recovery). Bilateral MEPs were recorded by tympanometry every 2 minutes. The slopes of the MEP-time functions during N(2)O breathing were calculated to the first observation of eustachian tube opening and divided by the estimated blood-ME N(2)O gradient to yield a N(2)O time constant. Sufficient data were available for 16 right and 11 left MEs to calculate the time constant. RESULTS: MEP did not change during the baseline period, but within 10 minutes of breathing the N(2)O mixture showed a progressive increase. The right-left correlation for the time constant was 0.87 (n = 10 ears, P = .001). Regression of the time constants on ME volume showed an inverse relationship (n = 23 ears, r = -41, P = .05). A better data fit was the curvilinear relationship predicted by a mathematical model of the mastoid acting as a ME ear gas reserve. CONCLUSIONS: These results support the tested hypothesis that the mastoid could serve as ME gas reserve.