Computed tomography in the study of the eustachian tube

A CT study was made of the eustachian tube in normal subjects as a control group and patients with chronic pathological inflammation of the middle ear. CT made it possible to perform contiguous scans at homologous depths of 1.5 mm, showing the whole interior of the tube in clear detail: the protympanum, the bony and cartilaginous portions, and the nasopharyngeal orifice. In most of the cases of pathological middle ear inflammations, the eustachian tube lumen was seen to be constricted and obstructed with isodense matter. Our present results also show the importance of extending CT investigations beyond the tympanic cavity and the mastoid to the eustachian tube in order to have more clinical data on its condition.     

Factors affecting recovery of mastoid aeration after ear surgery

Fifty-six patients after tympanomastoid surgery were examined to determine recovery of mastoid aeration and various pre- and intraoperative factors such as eustachian tube (ET) function, how the mastoid mucosa had been treated during surgery and whether or not a large silastic sheet had been placed in the middle ear or a ventilation tube used. Mastoid aeration recovery was confirmed by computed tomography in 27 of the 57 cases (47%) within 12 months of surgery. Among the factors examined, preservation of the epitympanic mucosa was found to be most important in mastoid aeration recovery. Use of a large silastic sheet to cover the area from the bony ET and tympanic cavity to epitympanum, aditus ad antrum or antrum was found to be of some help in recovery mastoid aeration after complete resection of the mucosa and mastoid air cells. Preoperative ET function, anterior tympanotomy and use of a ventilation tube did not influence recovery. Received: 12 August 1997 / Accepted: 9 September 1998     

Effect of middle ear infection upon the pneumatization of the mastoid: An experimental study in pigs

The suppression of the temporal bone's pneumatized cavities is commonly observed in chronic middle ear inflammatory disease, but this fact has not been explained in respect to its etiology, i.e., whether the poorly pneumatized cavity induces chronic middle ear infection or middle ear inflammatory condition suppresses the pneumatization of cellulae. We studied the effect of middle ear infection and eustachian tubal dysfunction in the early stage of life upon the development of pneumatization of the mastoid using 13 pigs, whose mastoid is comparable to that of man. We used two methods, the eustachian tube stenosis test and the tympanic membrane paraffin infusion test. The present study indicated that in six pigs infection of the middle ear in the early stage of life suppressed the normal development of pneumatization of the mastoid bone in pigs.     

完壁式乳突切开联合面隐窝开放治疗儿童分泌性中耳炎

目的 探讨完壁式乳突切开联合面隐窝开放在治疗儿童分泌性中耳炎中的临床价值.方法 回顾性分析2005年6月至2007年6月中山大学附属第二医院耳鼻咽喉头颈外科收治的17例(19耳)反复发作,行鼓膜置管3次以上无效的儿童分泌性中耳炎患者的临床资料,19耳均接受完壁式乳突切开联合面隐窝开放术治疗,其中7耳术中探杳咽鼓管欠通畅,同期行鼓膜置管术,置管后1～3个月拔管.结果 19耳中耳乳突炎性组织的病理检杳结果显示,9耳为中耳胆固醇肉芽肿,10耳为炎性肉芽.术后19耳均获痊愈,鼓膜形态正常.鼓室压图为A型曲线者16耳,C型曲线者3耳,且负压均在150 mm H2O(1 cm H2O=O.098 kPa)内.术后3个月纯音测听骨气导差均在15 dB以内,随访2～3年无复发.结论 儿童分泌性中耳炎如果反复发作,在多次行鼓膜置管无效的情况下,可考虑采用完壁式乳突切开联合面隐窝开放术式彻底清除病灶,从而建立长期有效的咽鼓管、鼓室、鼓窦、乳突的通气引流,该术式有效.     

中耳内窥镜解剖

目的 :探讨经不同途径的中耳内窥镜解剖所见。方法 :采用 0°,30°,90°的硬质内窥镜 ,对 17个颞骨标本进行了观察 (其中干标本 6个 ,湿标本 11个 ) ,内窥镜插入途径有 :外耳道 ;耳后切口 (包括乳突腔 鼓窦和乳突腔 后鼓室两条亚途径 ) ;中颅窝。结果 :外耳道途径 :采用 0°,30° ,90°的硬质内窥镜 ,所有鼓室结构都可看见 ,包括鼓室窦、面隐窝、上鼓室前隐窝等隐蔽处 ;乳突腔 鼓窦途径 :可以看见乳突腔、鼓窦、上中鼓室等结构 ;乳突腔 后鼓室途径 :可观察到乳突及中下鼓室结构 ;中颅窝途径 :可以观察到上鼓室、鼓窦、乳突腔及鼓室外侧壁的结构 ,中鼓室的大部分结构亦可观察到。结论 :经不同的途径行内窥镜术能清楚地观察到中耳各个结构 ,因此能减少胆脂瘤的复发率及评价术后中耳腔的状态 ,其中 30°的内窥镜提供的视野较好 ;但如经外耳道途径观察后上鼓室及经乳突腔 鼓窦途径观察后鼓室 ,则 90°内窥镜较适合     

Role of the mastoid in tympanic membrane reconstruction

Otologists have long debated the importance of the mastoid in determining the success or failure of tympanic membrane reconstruction. The pneumatic spaces within the mastoid represent an "air reservoir" which can be drawn upon during periods of eustachian tube dysfunction and buffer the middle ear against the development of detrimental negative pressures. Mastoid inflammatory disease, if untreated, may result in recurrent suppuration and graft failure. Small mastoid volume, aside from its well known association with chronic infectious middle ear disease, has been shown to effect adversely graft survival following myringoplasty. In 48 patients undergoing myringoplasty with simple mastoidectomy, neither small mastoid size nor inflammatory mastoid disease significantly decreased the rate of graft healing. This suggests that simple mastoidectomy is an effective means of repneumatizing the mastoid and eradicating mastoid sources of infection. The successful surgical creation of a pneumatized mastoid cavity in communication with the middle ear was confirmed by postoperative computerized tomographic (CT) scans. In failed cases, CT scanning predictably identified residual mastoid disease. Simple mastoidectomy is considered to be a safe and useful adjunct to myringoplasty in selected cases of chronic otitis media with perforation.     

Direct measurement of middle ear pressure through the eustachian tube

We report a method for measuring middle ear pressure through the eustachian tube. We used a 1-mm-diameter micro-tip catheter pressure transducer (Mikro-tip) and inserted this into the tympanic cavity through the eustachian tube. In preliminary studies, we measured four normal ears, two ears with tubal dysfunction, one ear with a dry perforation and 13 ears with otitis media with effusion (OME). Among those ears with OME, three showed negative middle ear pressure, three slight positive pressure and one normal pressure. These findings suggest that our transtubal method is reliable and useful for measuring middle ear pressure.     

Computed tomography in the study of the eustachian tube

Summary A CT study was made of the eustachian tube in normal subjects as a control group and patients with chronic pathological inflammation of the middle ear. CT made it possible to perform contiguous scans at homologous depths of 1.5 mm, showing the whole interior of the tube in clear detail: the protympanum, the bony and cartilaginous portions, and the nasopharyngeal orifice. In most of the cases of pathological middle ear inflammations, the eustachian tube lumen was seen to be constricted and obstructed with isodense matter. Our present results also show the importance of extending CT investigations beyond the tympanic cavity and the mastoid to the eustachian tube in order to have more clinical data on its condition.Presented at the First European Congress of Oto-Rhino-Laryngology and Cervico-Facial Surgery, Paris, 26–29 September 1988     

Direct measurement of middle ear pressure through the eustachian tube

Summary We report a method for measuring middle ear pressure through the eustachian tube. We used a 1-mm-diameter micro-tip catheter pressure transducer (Mikro-tip) and inserted this into the tympanic cavity through the eustachian tube. In preliminary studies, we measured four normal ears, two ears with tubal dysfunction, one ear with a dry perforation and 13 ears with otitis media with effusion (OME). Among those ears with OME, three showed negative middle ear pressure, three slight positive pressure and one normal pressure. These findings suggest that our transtubal method is reliable and useful for measuring middle ear pressure.     

Mastoid pneumatization of the patulous eustachian tube

The pathophysiology of the patulous eustachian tube (PET) remains unclear. The degree of mastoid cell pneumatization is considered an indicator of chronic inflammation of the middle ear. We used the mastoid cell area to investigate the relationship between past chronic inflammation of the middle ear cavity and a PET in 84 patients (20 to 83 years old). The mastoid cell size was calculated from radiographs and analyzed relative to the history of otitis media (OM). The controls were 100 normal ears. The patients' mastoid cell size was significantly suppressed versus that of the controls, in both 31 PET cases with and 53 PET cases without past OM. We surmise the possibility that the PET ears had experienced inflammation even when the patients had no history of OM and the tympanic membrane showed no OM sequelae. This study indicates the existence of some relationship between a history of chronic inflammation of the middle ear cavity and a PET.     

Eustachian tube function and the middle ear

Eustachian tube dysfunction has been linked to causing middle ear pathology. One of the sequelae seen is tympanic membrane retraction. Concern occurs when this physiological state becomes chronic, leading to adhesive otitis media followed by debris collection and fulminate cholesteatoma. This chapter explores the role the eustachian tube plays in regulating middle ear and mastoid aeration, the causes of eustachian tube dysfunction, and the treatment of this disorder.     

中耳胆固醇肉芽肿的诊断及治疗

目的:探讨中耳胆固醇肉芽肿的发病原因、诊断和接受中耳乳突手术治疗后的效果。方法:回顾性分析我院1999年8月～2004年4月接受中耳乳突手术治疗和经病理证实的18例(19耳)中耳胆固醇肉芽肿患者的临床资料,其中,接受完壁式乳突根治加鼓室探查加中耳置管术7耳,完壁式乳突根治加鼓室探查加听骨链成形加中耳置管术2耳,完壁式乳突根治加鼓室探查术3耳,完壁式乳突根治加鼓膜成形术2耳,开放式乳突根治加鼓室成形术4耳,单纯乳突切除术1耳。结果:置管者术后1～3个月拔除中耳通气管,鼓膜愈合良好;未置中耳通气管者,1～2个月鼓膜颜色正常。术后听力均有不同程度提高,纯音测听达到应用水平(语频气导平均听阈30dB以内)15耳(79%)。所有患者随访0.5～2年,除1耳因咽鼓管不通,长期留置中耳通气管外,其余患者无复发。结论:中耳胆固醇肉芽肿的病因为中耳炎症引起含气腔通气受阻,引流障碍及含气腔出血。确诊有赖于病理诊断。中耳乳突手术彻底去除病变,建立乳突鼓室咽鼓管良好的通气系统,是手术成功的关键。     

The tympano-frontal shunt: A procedure for the treatment of chronic eustachian tube insufficiency.

Eight ears with complications due to chronic eustachian tube insufficiency had insertion of a silicone rubber tympano-frontal shunt tube between the mastoid antrum and the ipsilateral frontal sinus. A one-way valve designed to open at-10 mm H₂O was placed on the tympanic end of the tube to minimize tube obstruction by ear secretions. Follow-up an average of 20 months post insertion showed six of the eight ears to have an aerated middle ear without fluid or tympanic membrane retraction or perforation.     

Aeration in chronic otitis media*

The mastoid air cell system must be looked upon as an air reservoir. The tympanic membrane is an air pressure regulator. The smaller the air volume of the mastoid the more pronounced is the volume displacement of the tympanic membrane. The more inefficient the Eustachian tube function, the more pronounced is the tympanic membrane displacement. The significance of these factors must be considered not only when discussing the etiology of chronic otitis media including cholesteatoma, but also when it comes to selecting procedures in restoring middle ear anatomy and physiology in chronic middle ear surgical disease.     

Experimental otitis media with effusion induced by lipopolysaccharide from Klebsiella pneumoniae: mucociliary pathology of the middle ear

We inoculated 100 micrograms/ml of lipopolysaccharide (LPS) from Klebsiella pneumoniae into the tympanic cavity of guinea pigs and examined the mucociliary pathology in the middle ear. Serous effusion was observed in the tympanic cavity of every animal on the first, third, and seventh day following the procedure, but the volume of the effusion had decreased to 0.2 ml on day 7. By that time, the ciliary activity in the opening to the eustachian tube within the middle ear had recovered to some extent, but in the middle ear distal to the opening no recovery was apparent. Our results show that cilia close to the eustachian tube play a more significant role in middle ear clearance than those in the middle ear distal to the tube. Compared with our previous study using 10 micron/ml of LPS, this study also demonstrates that inoculations with a higher concentration of LPS induces longer-term middle ear effusions.     

Anatomy of the guinea pig temporal bone.

The middle ear of guinea pigs has long been used for experimental studies, but no detailed information about its temporal bone anatomy is available. In 18 adult guinea pigs, the temporal bone, eustachian tube, and inner ear anatomy, in addition to the anatomy of the middle ear, were investigated under the dissection microscope. In addition to properties of the eardrum, ossicles, air cell system, and cochlea previously described, the appearance of Huschke's foramen and the crista stapedis in an adult guinea pig ear, the structure of the eustachian tube, the architecture of the internal auditory canal, and the communication of the mastoid cells with the tympanic bulla are described. Differences and similarities among guinea pigs, other experimental animals, and humans are discussed to show the advantages and disadvantages of the guinea pig ear for experimentation.     

颅脑外伤后顽固性脑脊液耳漏的手术策略和技巧研究

目的 探讨颅脑外伤后顽固性脑脊液耳漏手术治疗的技巧和策略.方法 采用颞下中颅底-乳突后联合入路,对11例颅脑外伤后中颅窝底缺损所致脑脊液耳漏且保守治疗无效的患者施行手术修补.结果 ①无需行乳突探查5例.因乳突为粉碎性骨折,在取下骨瓣前先行钛板固定2例.另外4例乳突粉碎骨折严重,术中将事先收集的颅骨碎屑回植到乳突缺损内,取头最长肌加生物胶加固;②术中发现有颅底广泛骨质缺损6例,脑组织疝入缺损中或乳突黏膜暴露广泛;③修补探查过程发现听骨链完整者3例,缺失2例,部分听小骨(锤骨)缺失2例,术中未探查听骨链者4例.术后随访2~11年,无复发.结论 ①当合并复杂性骨折时,通过幕上幕下联合,经颞下中颅底-乳突后联合入路,无疑是明智的选择,尤其是不稳定骨折累及乳突的患者;②对颅底骨折复杂而听力完全丧失的脑脊液耳漏患者,除了封闭外耳道外,尚需进行鼓室及咽鼓管填塞封闭,以防止假鼻漏的情况发生;③颈内动脉岩段与鼓室及咽鼓管关系密切,脑脊液耳漏修补手术中应避免手术误伤或骨折片意外伤及颈内动脉.     

Effect of artificial airway on ear complications from hyperbaric oxygen

Hyperbaric oxygen treatment is associated with an increased risk of barotrauma to the tympanic membrane and middle ear. An artificial airway may compromise normal eustachian tube function and equilibration of middle ear pressures. This retrospective study was designed to evaluate the risk of middle ear complications in 267 patients receiving hyperbaric oxygen (HBO) therapy and to compare those with and without artificial airways. Charts of all patients were reviewed for middle ear and tympanic membrane complications and myringotomy tube placement. Eighteen of the 267 patients had artificial airways. Seventeen (94%) of these 18 patients developed middle ear or tympanic membrane complications, and 11 (61%) required tympanostomy tubes for pain, hemo-tympanum, or serous otitis. In contrast, 114 (45.8%) of the 249 patients without airways developed ear complications, and 53 (21.3%) required tympanostomy tubes. These results suggest that patients with an artificial airway who are receiving HBO therapy are at greater risk for developing tympanic membrane and middle ear complications than nonintubated patients. Similarly, patients with artificial airways receiving HBO frequently require placement of tympanostomy tubes.     

Measurement of mucociliary function of the eustachian tube

Mucociliary function of the eustachian tube was measured with a radioisotopic method; 0.01 mL of a human serum albumin labeled with technetium 99m was instilled into the anterior part of the middle ear cavity either through a perforation or by puncturing the tympanic membrane, and its course was followed by a gamma-camera. In the normal eustachian tube, the velocity of the mucociliary transport was 0.7 to 1.1 mm/min. The mucociliary function was totally absent in chronic otitis media, in untreated secretory otitis media, and in the ear with a moist perforation of the tympanic membrane. The mucociliary transport returned to normal when the ear was clinically healed. It is assumed that the impairment of the mucociliary function of the eustachian tube and middle ear plays an important role in the pathogenesis of secretory otitis media and chronic ear discharge.     

Etiologic factors in non-suppurative otitis media

Two observations in non-suppurative otitis media, namely the serous fluid and the tympanic membrane retraction, may have separate explanations as to the etiologic factors. The first is the obstruction of the collecting lymphatic tubules of the middle ear and eustachian tube as they drain to the retropharyngeal lymphatics. This leads to a transudation of fluid in the middle ear or serous fluid. The second observation, retraction of the tympanic membrane, may be due to an absence or significant reduction of the surface tension lowering substance (Surface Active Membrane) of the eustachian tube, preventing the transmission of air to the middle ear from the nasopharynx.