Eustachian Tube Endoscopy in Patients With Chronic Ear Disease

Transcription

1 The Laryngoscope Lippincott Williams & Wilkins, Inc., Philadelphia 2000 The American Laryngological, Rhinological and Otological Society, Inc. Eustachian Tube Endoscopy in Patients With Chronic Ear Disease Christopher J. Linstrom, MD; Carol A. Silverman, PhD; Arie Rosen, MD; Lawrence Z. Meiteles, MD From the Department of Otolaryngology Head and Neck Surgery (C.J.L., C.A.S., A.R.), Department of Veterans Affairs Medical Center, East Orange, New Jersey; and the Departments of Otolaryngology Head and Neck Surgery (C.J.L., C.A.S., L.Z.M.) and Communicative Sciences (C.A.S.), The New York Eye and Ear Infirmary, New York, New York. Supported by the Department of Veterans Affairs, New Jersey Health System, under Contract V561P Editor s Note: This Manuscript was accepted for publication July 10, Send Correspondence to Christopher J. Linstrom, MD, Department of Otolaryngology Head and Neck Surgery, The New York Eye and Ear Infirmary, 310 East 14th Street, New York, NY 10003, U.S.A Objectives/Hypothesis: A paucity of research exists on trans eustachian tube endoscopy to evaluate the status of the eustachian tube. Fuller examination of the role of the eustachian tube in chronic ear disease is needed, particularly because the eustachian tube has been implicated in the chronicity and pathogenesis of chronic ear disease. Therefore the purpose of this study was to evaluate the eustachian tube, based on observations from trans eustachian tube endoscopy. Study Design: Twenty-two adult patients with chronic ear disease gave informed consent to participate in a prospective, trans eustachian tube endoscopic investigation. Methods: Flexible, fiberoptic, nonarticulating (outside diameter of 0.5 mm) and articulating (outside diameter of 1.0 mm) endoscopes (coherent fused bundle of 3,000 pixels) were employed. The eustachian tube endoscopy was performed under general endotracheal anesthesia as the initial part of a larger, otological surgical procedure for chronic ear disease. The endoscope was passed from the middle ear (transtympanic approach) to the nasopharynx. Results: The 0.5-mm endoscope passed entirely through the eustachian tube from the tympanic orifice into the pharyngeal orifice in 16% of the cases. Stenotic blockage occurred at the infundibulum in 37%, isthmus in 42%, and fossa of Rosenmüller in 5% of cases. The eustachian tube mucosa was abnormal in 64% of cases. The risk for abnormal eustachian tube mucosa was four times greater for persons with long-standing disease (>20 y) than for persons without long-standing disease (<20 y). The mean therapeutic efficiency of ossicular reconstruction was higher for the subgroup with normal than for the subgroup with abnormal eustachian tube mucosa. Conclusions: The findings of trans eustachian tube endoscopy provide objective evidence concerning eustachian tube status in persons with chronic ear disease and have implications for the timing of surgical intervention (ossicular reconstruction). Key Words: Eustachian tube, endoscopic techniques, tympanoplasty, chronic ear disease. Laryngoscope, 110: , 2000 INTRODUCTION Kimura et al. 1 were the first authors to introduce trans eustachian tube endoscopy in In 1994, Edelstein et al. 2 passed a flexible, micro-fiberoptic endoscope (0.55 mm with 2,000 pixels, 0.8 mm with 6,000 pixels, and 1.0 mm with 10,000 pixels) through the eustachian tube via its pharyngeal orifice for the purpose of evaluating middle ear status. Their approach required eustachian tube cannulation. Significant instrument failure from internal breakage of the fibers was encountered. Klug et al. 3 employed trans eustachian tube endoscopy (endoscope was passed from the pharyngeal orifice into the middle ear) in 40 temporal bone eustachian tube specimens of recently deceased persons, which lacked visible abnormalities. The data presented were obtained with a flexible, articulating micro-fiberoptic endoscope (0.8 mm diameter, 3,000 pixels), which was passed from the pharyngeal orifice through a tube catheter into the middle ear. The purpose of the investigation was to describe the frequency of occurrence of observation of various middle ear structures, using the endoscope. Klug et al. did not describe eustachian tube status in these specimens, except to indicate that the endoscope successfully negotiated the isthmus in 92.5% of the specimens. Su 4 was the first author to employ flexible, microfiberoptic, trans eustachian tube endoscopy (0.85-mm diameter) for the purpose of examining eustachian tube status in awake patients under local anesthesia. The approach to endoscopic insertion was transtympanic. The endoscope was passed from the middle ear to the pharyngeal orifice. Of the 18 patients, 13 had otitis media with effusion, 3 had chronic otitis media, and 2 had traumatic eardrum perforation. In 9 of the 18 patients, the endoscope successfully negotiated the isthmus section of the eustachian tube; the eustachian tube status in relation to its valve mechanism was described for these 9 patients. Eustachian tube dysfunction plays an important role in the pathogenesis of chronic ear disease. Lack of middle ear aeration from eustachian tube dysfunction is an

2 underlying cause of cholesteatomas, chronic tympanic membrane perforations, and atelectasis. Although the pathogenesis of chronic, suppurative otitis media is unknown, chronic eustachian tube dysfunction from chronic or recurrent nose and throat infections or anatomical tubal obstructions (partial or complete) has been implicated in the chronicity of chronic suppurative otitis media. 5 The eustachian tube tympanometric tests provide indirect rather than direct measures of eustachian tube status, and the test-retest reliability of these tests remains to be established for pathological ears. Despite the role of the eustachian tube in the chronicity and pathogenesis of chronic ear disease, a paucity of research exists on the eustachian tube status in chronic ear disease. Therefore the primary goal of this investigation was to directly assess the status of the eustachian tube of patients with chronic ear disease, using trans eustachian tube endoscopy. MATERIAL AND METHODS Patients Twenty-two adult patients with chronic ear disease gave informed consent to participate in a prospective, endoscopic investigation to describe the status of the eustachian tube at the time of surgery. Of the 22 patients, 13 had received ossicular reconstruction; the remaining 9 had not yet received ossicular reconstruction, because they were awaiting the second stage of surgery at the time of this writing. Of the 22 patients, 9 were men and 13 were women (mean age, 42 y; age range, y). The origin or cause was chronic suppurative otitis media in 11 patients, adhesive otitis media in 2, and cholesteatoma in 9. All patients received tympanoplasty with or without mastoidectomy. Of the 13 patients who had received ossicular reconstruction, 7 were men and 6 were women (mean age, 39 y; age range, y). The origin or cause was chronic suppurative otitis media in 7 patients, cholesteatoma in 4, and adhesive otitis media in 2. All received tympanoplasty with or without mastoidectomy, and all received ossicular reconstruction with an incus replacement prosthesis, partial ossicular replacement prosthesis, total ossicular replacement prosthesis, incus-stapes replacement prosthesis, or incus interposition. The remaining nine patients (two men and seven women; mean age, 45 y; age range, y) had undergone tympanoplasty with mastoidectomy, but had not yet received ossicular reconstruction (second stage). The origin or cause was chronic suppurative otitis media in four patients and cholesteatoma in five patients. No patient had a positive history of head trauma, vertigo, or systemic ototoxic drugs. At surgery, no patient was found to have a labyrinthine fistula or an inner ear invasion. At the time of surgery, notation was made regarding the mucosal status of the middle ear and the degree of ossicular involvement. Endoscopy Flexible, fiberoptic, nonarticulating endoscopes (Omega Endoscopic Technologies, San Diego, CA) with a fiber length of 40 cm, outside diameter of 0.5 mm, coherent fused bundle of 3,000 pixels, and a ring for fine focus were employed (Fig. 1) in 19 patients. In four patients, a flexible, fiberoptic, articulating endoscope (Omega Endoscopic Technologies) with a fiber length of 40 cm, outside diameter of 1.0 mm, coherent fused bundle of 3,000 pixels, and one-way articulation to 180 was used (Fig. 2). (Both endoscopes were employed in one patient.) The light source for Fig. 1. The 0.5-mm fiberoptic nonarticulating endoscope. the endoscopes was a 150-W xenon lamp (Karl Storz Endoscopy, Charlton, MA). The video equipment consisted of a Dyonics digital threechip video camera system (Smith & Nephew Endoscopy, Andover, MA) and a monitor (Sony Triniton video monitor, Sony Electronics, Inc., Montvale, NJ). The output of the video camera system was also routed to a picture-in-picture device (Dyonics digital PIP, Smith & Nephew Endoscopy), which combined two independent video signals (from the video camera system and operating microscope) into one video monitor display. The image from the operating microscope (Zeiss, Inc., Thornwood, NY) was routed through a camera (Storz Tricam SL NTSC, Karl Storz Endoscopy), the output of which was fed into the picture-in-picture device. The images displayed on the video monitor were stored on a Panasonic SVHS videocassette recorder (VCR), model AG-1980P (Panasonic Inc., Division of Matsushita Electric Corporation of America, Secaucus, NJ). To obtain the highest-quality image possible on the VCR, the output of the Dyonics PIP was routed through the VCR before being routed into the monitor. The source of the larger image on the monitor was the endoscope, and the source of the PIP image was the operating microscope. The monitoring equipment was placed into a single, rolling unit (Fig. 3). The eustachian tube endoscopy was performed with the patient under general endotracheal anesthesia as the initial part of a larger, otological surgical procedure for chronic ear disease. The endoscope was passed from the middle ear to the nasopharynx. The approach to the middle ear was transtympanic. Before the endoscope was passed through the eustachian tube, it was Fig. 2. The 1.0-mm fiberoptic articulating endoscope. 1885

3 Procedure Complete otolaryngological and audiological examinations were performed before and after surgery. The audiological assessment was performed in two-room, sound-treated audiometric suites by licensed and certified audiologists. The data from the latest preoperative tests, performed within the 2-week interval preceding surgery, and from the initial postoperative tests, performed between 10 and 12 weeks after surgery, were evaluated. These data enabled quantification of the therapeutic efficiency, which was defined as the difference between the preoperative and postoperative air-conduction thresholds. Fig. 3. Endoscopic imaging and recording setup. defogged, white-balanced (using sterile white gauze), and focused (by viewing a suture package with printing). If a tympanic membrane perforation was present, the endoscope was passed through the perforation. Otherwise, the tympanomeatal flap that was created and elevated as the initial surgical step in tympanoplasty with mastoidectomy permitted transtympanic eustachian tube endoscopy. A research assistant recorded the endoscopic eustachian tube and middle ear findings at the time of surgery. The data from the otolaryngological, endoscopic, and audiological evaluations and from surgery were maintained in a computerized database. RESULTS The 0.5-mm endoscope passed entirely through the eustachian tube from the tympanic orifice into the pharyngeal orifice in 16% of ears (3 of 19). Stenotic blockage was encountered at the infundibulum in 37% of ears (7 of 19), the isthmus in 42% of ears (8 of 19), and the fossa of Rosenmüller in 5% of ears (1 of 19). The 1.0-mm endoscope passed entirely through the eustachian tube in 33% (1 of 3). Stenotic blockage was encountered at the infundibulum in one ear and at the isthmus in the other ear. Data from the two ears for which blockage was encountered with the 1.0-mm endoscope were excluded from analyses that related eustachian tube blockage with other measures, because blockage could be attributed to endoscope diameter in those ears. The eustachian tube mucosal status was normal in 36% of patients (8 of 22) and abnormal in 64% (14 of 22). Table I shows the eustachian tube mucosal status in relation to site of eustachian tube blockage. Figure 4 presents a micro-endoscopic view illustrating normal eustachian tube mucosa. Figure 5 presents a micro-endoscopic view illustrating hypertrophic or moderately thickened eustachian tube mucosa. The two patients with changes in the eustachian tube mucosa that resembled tympanosclerosis of the middle ear also had tympanosclerotic middle ear mucosa (involving TABLE I. Eustachian-Tube Mucosal Status. Site of Blockage Eustachian-Tube Mucosal Status Subjects (n) Infundibulum (n 8) Normal 3 Hypertrophic or moderately thickened 5 Polypoid 0 Tympanosclerotic-like 1 Isthmus (n 9) Normal 2 Hypertrophic or moderately thickened 6 Polypoid 0 Tympanosclerotic-like 1 Fossa of Rosenmüller (n 1) Normal 1 Hypertrophic or moderately thickened 0 Tympanosclerotic-like 0 No blockage (n 4) Normal 2 Hypertrophic or moderately thickened 2 Tympanosclerotic-like

4 Fig. 4. A micro-fiberoptic endoscopic view (0.5-mm, nonarticulating endoscope) within a right-side eustachian tube of a patient with chronic suppurative otitis media. View at the isthmus (15 mm from the middle ear orifice of the eustachian tube) demonstrates normal eustachian tube mucosa. The lumen (L) is marked and is patent. The axes of orientation (S for superior, I for inferior, P for posterior, and A for anterior) are shown. The white area represents a highlight on the mucosa. Fig. 5. A micro-fiberoptic endoscopic view (1-mm articulating endoscope) within a right-side eustachian tube of a patient with chronic suppurative otitis media. In the patient the endoscope passed all the way into the nasopharynx (140 mm). View was obtained while the endoscope was withdrawn in mid passage. The axes of orientation (S for superior, I for inferior, P for posterior, and A for anterior) are shown. Note the lumen (L) of the eustachian tube and, inferiorly, the hypertrophic mucosa (M) of the eustachian tube. The white areas represent highlights on the mucosa. the ossicular chain in one patient and not involving the ossicular chain in the other). The origin or cause of chronic ear disease was chronic suppurative otitis media in one patient and cholesteatoma in the other patient. Both had long-standing chronic ear disease (25 44 y duration of disease). Of the seven patients with tympanosclerotic middle ear mucosa, 29% (2 of 7) had changes in the eustachian tube mucosa which resembled tympanosclerosis that was seen in the middle ear. Of the patients with cholesteatoma, 89% (8 of 9) had abnormal eustachian tube mucosa and 88% (7 of 8) had nonpatent eustachian tubes. Of the patients with chronic suppurative otitis media, 55% (6 of 11) had abnormal eustachian tube mucosa and 73% (8 of 11) had nonpatent eustachian tubes. Of the patients with adhesive otitis media, both had abnormal eustachian tube mucosa. In the patient with adhesive otitis media, who was endoscopically investigated with a 0.5-mm endoscope, the eustachian tube was observed to be nonpatent. Of the four patients with patent eustachian tubes, the middle ear mucosa was normal in 25% (1 of 4), none (0%) had type I Bellucci classification preoperatively, and none (0%) had positive histories of prior tympanoplasty with mastoidectomy. The origin or cause was cholesteatoma in 25% of patients (1 of 4). Of the 18 patients with nonpatent eustachian tubes, the middle ear mucosa was normal in 33% (6 of 18), 28% (5 of 18) had type I Bellucci classification preoperatively, and 56% (10 of 18) had positive histories of prior tympanoplasty with mastoidectomy. The origin or cause was cholesteatoma in 44% of patients (8 of 18). Of the eight patients with normal eustachian tube mucosa, the middle ear mucosa was normal in 50% (4 of 8), 38% (3 of 8) had type I Bellucci classification preoperatively, and 25% (2 of 8) had positive histories of prior tympanoplasty with mastoidectomy. The origin or cause was cholesteatoma in 13% of patients (1 of 8). Of the 14 patients with abnormal eustachian tube mucosa, none (0%) had normal middle ear mucosa, 14% (2 of 14) had type I Bellucci classification preoperatively, and 57% (8 of 14) had positive histories of prior tympanoplasty with mastoidectomy. The origin or cause was cholesteatoma in 57% of patients (8 of 14). The odds ratio for abnormal eustachian tube mucosa associated with a long duration of chronic ear disease ( 20 y) was 4.0. This odds ratio approached but did not achieve significance (P.1567), suggesting a trend toward a four-times-greater risk of abnormal eustachian tube mucosa in patients with long-standing disease as compared with patients without long-standing disease. Within the group that received ossicular reconstruction, the mean three-frequency therapeutic efficiency (based on 500, 1,000, and 2,000 Hz) was 9 db higher for the subgroup with normal eustachian tube mucosa (4 patients) than for the subgroup with abnormal eustachian tube mucosa (8 patients). Similarly, the mean fourfrequency therapeutic efficiency (based on 500, 1,000, 2,000, and 3,000 Hz) was 9 db higher for the subgroup with normal eustachian tube mucosa than for the sub- 1887

5 group with abnormal eustachian tube mucosa. Of the subgroup with normal eustachian tube mucosa, no patient (0%) had therapeutic efficiency values less than 12 to 13 db (depending on whether the average was based on three or four frequencies). On the other hand, 50% (4 of 8) of the subgroup with abnormal eustachian tube mucosa had average therapeutic efficiency values less than 12 db, and 38% had zero or negative average values. Three nonarticulating, trans eustachian tube endoscopes were used for the investigation of the eustachian tube status in 19 of the 22 patients. On average, 6.3 patients were investigated per single nonarticulating, trans eustachian tube endoscope. Although breakage has occurred within the fiberoptic cable inside the endoscope, no endoscope has broken within the patient DISCUSSION The passage of the 0.5-mm endoscope from the infundibulum of the eustachian tube into the nasopharynx was successfully negotiated in only 16% of the ears with chronic ear disease. The tip of the 0.5-mm endoscope was readily maneuvered, despite the absence of an articulation knob. Therefore the high frequency of eustachian tube blockage that was observed for this sample of patients with chronic ear disease suggests that chronic inflammation or infection limits the internal diameter of the eustachian tube. Once the scope negotiated the isthmus, it generally passed through into the nasopharynx. A limitation of this study was the lack of a control group, which cannot be readily obtained because of the difficulty of obtaining consent for trans eustachian tube endoscopy from patients without chronic ear disease. Although the techniques and equipment differed from those used in the present investigation, the data from Klug et al. 3 showing that an 0.8-mm endoscope passed through a normal isthmus in 92.5% of the cases suggest that the 0.5-mm endoscope we employed would easily negotiate a normal isthmus. The results of our pilot data with custom-developed trans eustachian tube endoscopes containing various numbers of pixels ranging from 1,000 to 10,000 suggested that at least 3,000 pixels were required for an adequate picture quality. A further decrease in the outside diameter of the articulating endoscope below 1.0 mm led to an unacceptable sacrifice in the adequacy of the picture, and to unstable articulation. The ability to negotiate the endoscope through the eustachian tube in its entirety was not dependent on the finding of normal eustachian tube mucosa, absence of cholesteatoma, or a type I Bellucci classification before surgery. Of the four patients without eustachian tube blockage, 50% had abnormal eustachian tube mucosa, 25% had cholesteatoma, and 0% had type I Bellucci classification before surgery. The finding that 100% of the 10 patients with positive histories of tympanoplasty with mastoidectomy had nonpatent eustachian tubes suggests that such history may be predictive of a nonpatent eustachian tube. Because the status of the eustachian tube mucosa was abnormal in 89% of the 9 patients with cholesteatoma, cholesteatoma may be a risk factor for abnormal eustachian tube mucosa. The presence of tympanosclerotic middle ear mucosa was suggestive of the presence of tympanosclerotic eustachian tube mucosa as 29% of the 7 patients with tympanosclerotic middle ear mucosa also had tympanosclerotic eustachian tube mucosa, and tympanosclerotic eustachian tube mucosa was not observed in ears without tympanosclerotic middle ear mucosa. The odds ratio for abnormal eustachian tube mucosa associated with a long duration of chronic ear disease ( 20 y) approached but did not achieve significance (insufficient sample size). Nevertheless, it showed a trend toward a four-times-higher risk of abnormal eustachian tube mucosa for persons with long-standing chronic ear disease than for those without long-standing chronic ear disease. Our finding that the mean therapeutic efficiency of ossicular reconstruction was 9 db higher in ears with normal than in ears with abnormal eustachian tube mucosa suggests that knowledge of the objective status of the eustachian tube mucosa may have clinical significance for predicting prognosis for the hearing outcome of ossicular reconstruction. This finding suggests that the therapeutic efficiency of ossicular reconstruction may be reduced with a long hiatus between onset of chronic ear disease and surgical intervention (ossicular reconstruction). Largesample studies are needed to substantiate these findings. CONCLUSION The results of trans eustachian tube endoscopy for this sample of patients with chronic ear disease indicate that the eustachian tube isthmus often is substantially narrowed by chronic ear disease. Our endoscopic findings provide objective data relating to the condition of the eustachian tube mucosa and eustachian tube patency in patients with chronic ear disease at the time of surgery. The findings also suggest that patients with chronic ear disease and a positive history of tympanoplasty with mastoidectomy may be at increased risk for a nonpatent eustachian tube. The risk of abnormal eustachian tube mucosa appeared to be greater for patients with cholesteatoma than for patients without cholesteatoma. Longstanding chronic ear disease appeared to be associated with increased risk of abnormal eustachian tube mucosa. The status of the eustachian tube mucosa has potential significance in predicting the therapeutic efficiency of ossicular reconstruction. ACKNOWLEDGMENTS The authors thank Tina Presutti for her invaluable assistance in data collection and study setup, Dr. William Spencer for his assistance with endoscopic examination of the eustachian tube, and Mati Guzzo-Crocamo for her contributions toward data collection. Thanks also are extended to Nancy Gilston, Denise Haight, and Sharon Kupfer for their contributions toward audiological assessment of the patients.

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