The role of high-resolution CT in evaluating disease of the posterior tympanum

The posterior tympanum consists of several irregular eminences, ridges, and sinuses. These sinuses do not communicate with the mastoid air cell system, and cholesteatoma and/or granulation tissue prefer to fill them. This area cannot be visualized with ease by the usual surgical approach, and is thus quite important for surgeons. Recent developments in high-resolution computed tomography (HRCT) allow more than ever precise identification of subtle changes in the posterior tympanum. Axial HRCT sections provide essential information for the preoperative evaluation of the posterior tympanum. The performance of surgeons has been promoted both in evaluation and treatment planning of patient with suspected posterior tympanic lesions. HRCT findings were compared with the operative findings in 52 patients (54 ears) who had the operation for chronic otitis media. Important findings by HRCT diagnosis of posterior tympanum are as follows: (1) Bone destruction in the posterosuperior part of the tympanic anulus and in the lateral wall of the facial sinus are the important findings for the diagnosis of invasion of cholesteatoma in the posterior tympanum. (2) Similarly important finding is the bone destruction of the pyramidal eminence. This was found in 6 of 9 cases with cholesteatomas extending into the sinus tympani. (3) The soft tissue density in the posterior tympanum does not necessarily indicate pathological processes. Effusion in the posterior tympanum is imaged as soft tissue density, and can not be differentiated from cholesteatoma or granulation by present HRCT.     

后鼓室解剖结构测量观察及临床意义

目的通过研究后鼓室有关解剖结构,及对后鼓室入路手术的径路进行观察、测量,为中耳相关手术入路提供理论参考依据。方法取成人30个干性颅骨的60侧颞骨,用耳科钻完成乳突腔气房“轮廓化",充分暴露后鼓室的各相关结构,在手术显微镜下进行解剖学观察,并对有关结构之间的距离进行测量。结果颞骨标本解剖观察结果,锥隆起至鼓索隆起的距离（3.22±0.41）mm、锥隆起至面神经管直线距离（3.59±0.48）mm、鼓索后小管的长度（9.44±1.65）mm;面神经管锥曲至鼓索隆起间的距离（3.34±0.42）mm、面神经锥曲至水平半规管距离（1.54±0.25）mm、面神经锥曲至后半规管距离（2.15±0.29）mm。面神经垂直段从外向内观察大部分呈后凸弧形下行,但有2例（3.33%）呈直线型垂直下行。面神经镫骨肌支全部从面神经管前壁穿出,鼓索神经自面神经管外发起9例（15%）,自面神经管下1/3处分出49例（81.67%）,自1/3处分出2例（3.33%）。结论经后鼓室进路手术开放面神经隐窝时,鼓索隆起至面神经管锥曲和至锥隆起的距离可作为开放面神经隐窝的宽度,面神经管与锥隆起可作为手术中互为寻找的依据。术中处理面神经隐窝病变时勿随意磨低锥隆起及鼓索隆起,以免损伤面神经镫骨肌支及鼓索神经。     

Application of high resolution computer tomography in external ear canal cholesteatoma diagnosis

Objective

To evaluate High Resolution Computer Tomography (HRCT) in the diagnosis of external ear canal cholesteatoma.

后鼓室病灶清理对干耳影响的临床研究

目的:探讨中耳手术中常规开放后鼓室对术后干耳的影响。方法:回顾性分析168名中耳手术病例,按术中是否开放后鼓室分组,比较2组术后干耳率。结果:未开放后鼓室组和开放后鼓室组术后干耳率分别为81.7%(67/82)和91.9%(79/86);未开放后鼓室组中胆脂瘤型和骨疡型患者干耳率分别为78.9%(30/38)和84.1%(37/44),开放后鼓室组这2型干耳率分别为88.1%(37/42)和95.5%(42/44);未开放后鼓室组中行乳突根治术和鼓室成形术患者术后干耳率分别为81.8%(36/44)和84.6%(31/38),而开放后鼓室组则分别为91.3%(42/46)和92.5%(37/40)。结论:中耳手术中常规开放后鼓室不仅有利于清理隐匿的病灶,而且有利于最大限度的修低面神经嵴,通畅引流,最终提高术后干耳率。     

The ponticulus: an anatomic study.

HYPOTHESIS: The purpose of this study was to resolve anatomic ambiguities of the ponticulus so the surgeon will be better able to remove disease from the posterior tympanum. BACKGROUND: The first step in refining an operative approach is to acquire a thorough understanding of the anatomy. A detailed study of one structure of the posterior tympanum, the ponticulus, has not yet been reported. METHODS: Fifty temporal bone plugs harvested from human cadavers were studied. The presence or absence of the ponticulus, its configuration, and its proximity to other middle ear structures were recorded for each temporal bone. RESULTS: There was complete formation of the ponticulus in 33 of the 50 specimens. In 7, only a remnant of the ponticulus formed, and it was completely absent in 10 of the 50 specimens. In the 33 specimens in which the ponticulus was present, it measured less than 1 mm in thickness in 22, it was larger than 1 mm in 7, and in 4 specimens it extended down to the floor of the middle ear as a sheet of bone. In 8 specimens, the ponticulus lay just adjacent to the stapes. CONCLUSION: The ponticulus is present in the majority of ears. It is best defined as a bridge of bone from the pyramidal eminence to the promontory and most commonly occurs as a thin, bony structure. This definitive study of the ponticulus will allow the otologic surgeon to better remove disease from the posterior tympanum.     

Posterior sinus of the middle ear

OBJECTIVES: This study defines the anatomy of the posterior sinus of the middle ear and its relationship with the sinus tympani. METHODS: Fifty-one temporal bone plugs harvested from human cadavers were studied. The depth and width of the posterior sinus, its relationship to surrounding structures, and the structure that separates it from the sinus tympani were studied. RESULTS: The posterior sinus, positioned just posterior to the oval window, was 1 mm or less in depth, and the width of the opening 1.5 mm or less. A ridge of bone from the floor of the middle ear separated the posterior sinus from the sinus tympani in 82% of specimens. In 10% a sheet of bone separated the two sinuses, and in 8% the sinus tympani and posterior sinus formed one confluent recess. CONCLUSIONS: This is the first study that describes the anatomy of the posterior sinus of the middle ear. This sinus is separated from the more inferiorly located sinus tympani by a ridge of bone, not by the ponticulus as was previously thought, and it is no larger than 1 mm in depth and 1.5 mm in width. The results from this study give the otologic surgeon knowledge of middle ear anatomy that he or she can use when removing cholesteatoma, granulation tissue, or retracted epithelium from the posterior tympanum.     

Ventilation and passages in the middle ear. A study by HRCT in patients with attic cholesteatoma]

Operative records of 75 patients with acquired attic cholesteatoma were evaluated and compared with preoperative HRCT findings. The cholesteatoma extensions were classified into five groups as follows; Group 1 (cholesteatoma limited to the attic, 9 cases), Group 2 (cholesteatoma occupying both the attic and the aditus, 5 cases), Group 3 (cholesteatoma extending down to the posterior tympanum, also occupying an area as in Group 2, 6 cases), Group 4 (cholesteatoma occupying the attic, the aditus and the mastoid antrum, 14 cases), and Group 5 (cholesteatoma extending down to the posterior tympanum, also occupying an area as in Group 4, 41 cases). Ventilatory conditions, or the existence of soft tissue density, were evaluated by HRCT at such locations as the supratubal recess, mesotympanum, anterior and posterior parts of the tympanic isthmus, epitympanum, and mastoid antrum. Results are as follows. In Group 1, all these locations were aerated with the exception of a few cases. In Group 2, complete opacification was observed in almost all of the antrums. Soft tissue masses involved the anterior and/or posterior parts of the tympanic isthmus in both Groups 3 and 5. In Group 3, the posterior part of tympanic isthmus was less aerated than the anterior part of tympanic isthmus. In Group 5, all locations were filled with soft tissue density except the supratubal recess and the mesotympanum, where some degree of aeration was observed. These results indicate that blockage of the ventilatory passages is not essential for formation of an attic cholesteatoma. Soft tissue density in HRCT is not the cause, but rather, the result of extension of a cholesteatoma.     

“Transcanal view” computed tomography reformat: Applications for transcanal endoscopic ear surgery

PurposeTranscanal endoscopic ear surgery (TEES) is an increasingly used surgical approach for otologic surgeries, but no en face preoperative imaging format currently exists. We aim to assess the utility of a transcanal high resolution computed tomography (HRCT) reformat suitable for TEES preoperative planning.Materials and methodsPreoperative HRCTs of patients with middle ear pathologies (cholesteatoma, otosclerosis, and glomus tympanicum) who underwent TEES were obtained. Axial image series were rotated and reformatted ?90 or +90 degrees for left and right ear surgeries, respectively, where additional rotation along the left-right axis was performed to align the transcanal series with the plane of the external auditory canal. Quantitative measurements of middle ear structures were recorded. Consecutive transcanal reformatted sections were then reviewed to identify critical middle ear anatomy and pathology with corresponding TEES cases.ResultsThe aforementioned methodology was used to create three transcanal view HRCTs. The mean left-right axis degree of rotation was 4.0 ± 2.2 degrees. In the cholesteatoma transcanal HRCT, areas of cholesteatoma involvement in middle ear compartments (e.g. epitympanum) and eroded ossicles were successfully identified in the corresponding case. In the otosclerosis transcanal HRCT, areas for potential otosclerotic involvement were visualized such as the round window as well as a low-hanging facial nerve. In the glomus tympanicum transcanal HRCT, the span of the glomus tympanicum was successfully visualized in addition to a high riding jugular bulb.ConclusionA transcanal HRCT reformat may aid preoperative planning for middle ear pathologies. This novel reformat may help highlight patient-specific anatomy.     

1～6岁儿童振动声桥圆窗植入术相关解剖结构的CT测量

目的应用颞骨高分辨率CT测量儿童振动声桥圆窗植入术的相关解剖结构,为术前评估提供理论参考。方法以50例15个月～6岁因重度感音性聋拟行人工耳蜗植入术且术前颞骨薄层CT扫描示中耳、内耳均正常的患儿为研究对象,在其术前颞骨高分辨率CT扫描轴位片上测量振动声桥圆窗植入术的相关解剖结构数据,如圆窗龛的宽度和深度、锥隆起的高度、面神经至圆窗龛和外耳道后壁的距离等,并比较不同耳别、性别及年龄组间的差异。结果 50例儿童各指标测量均值分别为:圆窗龛的宽度2.02±0.20mm,圆窗龛的深度1.25±0.19mm,圆窗龛层面面神经管外缘至骨性外耳道后壁的最短距离3.99±0.53mm,面神经骨管内缘至圆窗龛的距离5.21±0.37mm,锥隆起的高度2.09±0.23mm。各测量指标耳别间、不同性别间、不同年龄组间差异均无统计学意义(P>0.05),锥隆起高度与面神经至圆窗龛的距离之间无明显相关性(r=0.331,P>0.05)。结论面神经隐窝等相关解剖结构在出生后可能已经基本发育完成;对国人1～6岁儿童行振动声桥圆窗植入术从解剖理论上具有可行性;术前相关结构的CT测量可为手术提供重要参考。     

Cholesteatoma extending into the internal auditory meatus

We report our experiences in managing a patient with cholesteatoma complicated by meningitis, labyrinthitis and facial nerve palsy. The antero-inferior half of the tympanum was aerated but the postero-superior portion of the tympanic membrane was tightly adherent to the promontry mucosa. An attic perforation was present at the back of the malleolar head. High-resolution computed tomography also uncovered a fistula in the lateral semicircular canal. Surgical exploration of the middle ear cavity demonstrated that both the vestibule and cochlea were filled with cholesteatoma, and the cholesteatoma extended into the internal auditory meatus through the lateral semicircular canal fistula. The cholesteatoma was removed by opening the vestibule and cochlea with a preservation of the facial nerve. Post-operatively, an incomplete facial palsy remained, but has improved slowly. There is no sign of recurrence to date after a 3-year period of observation.     

Cholesteatoma extending into the internal auditory meatus

We report our experiences in managing a patient with cholesteatoma complicated by meningitis, labyrinthitis and facial nerve palsy. The antero-inferior half of the tympanum was aerated but the postero-superior portion of the tympanic membrane was tightly adherent to the promontry mucosa. An attic perforation was present at the back of the malleolar head. High-resolution computed tomography also uncovered a fistula in the lateral semicircular canal. Surgical exploration of the middle ear cavity demonstrated that both the vestibule and cochlea were filled with cholesteatoma, and the cholesteatoma extended into the internal auditory meatus through the lateral semicircular canal fistula. The cholesteatoma was removed by opening the vestibule and cochlea with a preservation of the facial nerve. Post-operatively, an incomplete facial palsy remained, but has improved slowly. There is no sign of recurrence to date after a 3-year period of observation.     

灌流模式软骨膜-软骨-软骨膜复合体重建上鼓室外侧壁的临床应用

目的 探讨耳内镜灌流模式下应用软骨膜-软骨-软骨膜复合体重建上鼓室外侧壁在上鼓室胆脂瘤(包含外耳道胆脂瘤和中耳胆脂瘤)手术中的临床治疗效果。方法 回顾性分析纳入研究的29例患者(外耳道胆脂瘤14例,中耳胆脂瘤15例),其上鼓室全部被胆脂瘤侵犯破坏,彻底清除上鼓室及听骨链病变后,应用耳内镜在灌流模式下选取耳屏或耳甲腔软骨膜-软骨-软骨膜复合体重建上鼓室外侧壁。结果 术前气导听力(42.51±3.55)dBHL,术后3个月为(26.22±5.12)dBHL;术前气骨导差(28.67±6.31)dBHL,术后3个月为(13.11±6.56)dBHL,经比较差异均具有统计学意义(P均<0.05)。术后定期随访,出现耳鸣5例,眩晕3例,内陷袋1例,人工听骨赝复物脱出1例,外耳道狭窄3例,鼓膜穿孔1例;耳鸣、耳闷、眩晕经对症处理后症状消失,内陷袋及人工听骨赝复物脱出的患者听力改善尚可,继续观察随访;鼓膜穿孔及外耳道狭窄再次行手术处理后痊愈。结论 耳内镜灌流模式下软骨膜-软骨-软骨膜复合体在清除胆脂瘤后,重建上鼓室外侧壁,可有效恢复中耳鼓室解剖结构,显著提高患者术后听力,促进患者术后恢复,降低...     

先天性中耳胆脂瘤

目的探讨先天性中耳胆脂瘤的位置、范围、临床症状、影像学特征及手术治疗。方法本文回顾性分析了解放军总医院耳鼻咽喉-头颈外科自1995年1月～2005年10月诊治的952例胆脂瘤患者的治疗结果,对其中10例先天性中耳胆脂瘤的起源、临床特征及手术前后的听力进行了评估。结果10例先天性中耳胆脂瘤患者的平均年龄为16岁(10～24岁),其中7例为男性,3例为女性,出现症状到临床确诊的平均时间为2年。术前平均纯音听阈为55dB,平均气-骨导差为45dB,有2例患者的鼓膜像上可以看到典型的先天性中耳胆脂瘤表现。所有病例均进行了高分辨率颞骨CT扫描。8例术前分别被诊断为耳硬化症或听骨链畸形。所有病例都在外耳道径路鼓室探查清除胆脂瘤后进行了一期鼓室成型术,除了1例因为病变广泛选择了完壁式乳突根治和鼓室成型术。本组所有病例的胆脂瘤均位于中-后鼓室,主要是在砧镫关节处。术后的平均气-骨导差小于20dB。所有病例术后至少随访1年半,2例病人因为术后听力下降进行了二期手术。本组病例中经手术探查或CT复查,没有发现胆脂瘤残留或复发。结论原发性中耳胆脂瘤临床罕见,常被延误诊断,其预后和残留、复发比例主要决定于病变范围。     

高分辨CT检查面神经管与周围结构解剖关系

目的探讨高分辨CT（high resolution CT,HRCT）中面神经管与周围结构解剖关系,为进行手术操作提供可靠信息。方法回顾2007年8月～2009年9月我院行颞骨HRCT检查且无颞骨病变的患者118例,其中男性65例,女性53例;在工作站上对轴位及重组出的矢状位、冠状位,观察各段面神经管周围重要结构的距离进行测量,比较不同侧别、性别上述测量值有无差异。结果垂直段前缘距外耳道后壁距离成人为（4 23±0.73）mm,垂直段距乙状窦前壁距离（9.93±2.16）mm,垂直段距蜗窗距离（3.21±0.31）mm,垂直段距鼓岬外缘最短距离（4.32±0.57）mm,砧骨短脚距面神经锥段距离（3.32±0.37）mm,水平段距蜗窗水平距离（2.28±0.48）mm,水平段距鼓岬外缘水平距离（2.23±0.18）mm,面隐窝宽度（5.12±0.31）mm。结论 HRCT是研究面神经管与周围结构影像解剖的优良方法,可为耳显微外科手术中避免面神经的意外伤害提供可靠信息。     

Temporal bone measurements on high-resolution computed tomography

The distances between the important neural and vascular structures in normal temporal bones were measured by using high-resolution computed tomography (HRCT). We examined 100 normal ears in 50 subjects ranging in age from 15 to 72 years (mean age 39 years). We measured the distances from the medial lip of the posterior wall of the internal auditory canal to the medial wall of the vestibule (mean 9.7 mm), from the cochlea to the tympanic segment of the facial canal (mean 1.76 mm), from the medial wall of the vestibule to the lateral aspect of the lateral semicircular canal (mean 8.03 mm), and from the external auditory canal to the lateral sinus (mean 13.2 mm). HRCT examination is the best method for defining the morphology of temporal bone.     

中耳胆脂瘤并发迷路瘘管的临床特征

目的 探讨中耳胆脂瘤并发迷路瘘管的诊断和处理方法.方法 回顾分析2012年9月至2018年9月在我院住院行中耳胆脂瘤手术患者658例,其中并发迷路瘘管52例(7.9％),收集其术前临床表现、纯音听阈结果、影像学表现,术中探查所见及处理方式,术后恢复情况等结果进行统计学分析.结果 52例迷路瘘管患者术前有眩晕症状32例(...     

Relationships between facial canal dehiscence and other intraoperative findings in chronic otitis media with cholesteatoma

ObjectiveWe investigated the relationship between facial canal dehiscence and intraoperative middle ear and mastoid findings in patients operated on for cholesteatoma.MethodsWe examined retrospectively 334 patients who had been operated on for cholesteatoma in Izmir Katip Celebi University, Ataturk Research and Training Hospital, ENT Clinic, between April 1997 and April 2010. The patients were examined for facial canal dehiscence according to age, gender, side of the ear, surgery type, first or revision surgery, localization of the facial canal dehiscence, spread of the cholesteatoma, with the presence of lateral semi-circular canal (LSCC) fistula and any defect in the ossicle chain, and destruction in the posterior wall of the external auditory canal(EAC).ResultsOf the patients, 23.6% had facial canal dehiscence and detected most commonly in the right ear 28.9% and tympanic segment, 83.5%. Facial canal dehiscence was found to be 24.2-fold more common in patients with LSCC fistula and 4.1-fold more common in patients with destruction in the posterior wall of the (EAC). In patients located cholesteatoma in tympanic cavity + antrum and the tympanic cavity + all mastoid cells and with incus and stapes defect, increased incidence of dehiscence. Age, first or revision operation and canal wall down tympanoplasty (CWDT) or canal wall up tympanoplasty (CWUT) did not affect the incidence of dehiscence.ConclusionsThat the likelihood of facial canal dehiscence occurrence is increased in patients with LSSC fistulas, destruction in the posterior wall of the EAC, or a stapes defect is important information for surgeons.     

经耳内镜鼓窦与上鼓室入路人工耳蜗植入的解剖研究

目的 探讨经耳内镜鼓窦、上鼓室自然通道人工耳蜗植入术的可能性.方法 在4例冰冻成人正常颞骨标本开展新手术入路,并测量相关参数,术后中耳高分辨CT加以证实.结果 所有标本均切开鼓窦,经鼓窦入口、上鼓室、中鼓室放置植入电极,在耳内镜下经外耳道鼓室切开显露蜗窗龛,通过蜗窗植入电极,未损伤鼓索神经、面神经.鼓后峡宽度(4.65...     

乳突鼓室成形手术的分期问题

目的探讨分期乳突鼓室成形术在以提高听力为目的的功能性耳显微外科中的作用.方法本文总结了海军总医院1993-2003年3月2700例各类中耳手术中分期鼓室成形术102例,随访1～5年,手术主要类型为保留外耳道后壁的乳突切开鼓室成形术、切除外耳道后壁的乳突切开鼓室成形术,保留骨桥的乳突切开鼓室成形术,文中对分期手术的理念、适应症选择、手术方式选择及移植筋膜感染、不愈合等问题进行了分析.结果 102例分期手术中,85例(83.3%)愈合良好,其中7例一期术后干耳,但二期手术中发现后鼓室及鼓窦处胆脂瘤珠及肉芽组织;17例存在不同程度的问题,出现率16%,包括一期术后出现移7植物穿孔或延迟愈合,在后鼓室、鼓窦、面神经隐窝等处发现胆脂瘤肉芽组织,但鼓室粘膜有不同程度的修复.102例分期手术术后1年气导听力(O.5K、1k、2k平均听力)较术前提高15 dBHL.结论在彻底清除病灶基础上,合理而有计划的行分期手术修复鼓室粘膜,恢复中耳含气空腔,为听骨链重建创造条件,以提高听力,不失为较佳的选择.     

慢性化脓性中耳炎及中耳胆脂瘤术前颞骨CT及耳内镜评估的意义

目的 探讨颞骨CT及耳内镜对慢性化脓性中耳炎静止期及中耳胆脂瘤术前评估的重要性。方法 回顾性分析慢性化脓性中耳炎静止期及中耳胆脂瘤患者42耳病历资料,从CT、耳内镜及术中发现进行分析。结果 ①根据CT结合术中所见,慢性化脓性中耳炎静止期CT分型分为单纯型、硬化灶型、肉芽型、硬化灶肉芽型。胆脂瘤型CT主要表现为听骨链消失或锤砧关节消失,乳突大部分呈硬化型,少部分为板障型,上鼓室鼓窦扩大,上鼓室、中鼓室甚至后鼓室乳突腔为软组织影占据,部分病例外半规管骨质破坏、面神经管水平段骨质破坏,部分病例外耳道后壁骨质破坏;单纯型CT示中耳鼓室乳突呈不完全气化型;硬化灶型CT示中耳鼓室乳突呈硬化型,病变局限于中鼓室,锤骨柄及镫骨周围有“类似骨质影”包裹;肉芽型、硬化灶肉芽型CT相似,示病变累及鼓室及乳突,听骨链基本完整,面神经管水平段骨质完整,但硬化灶型与肉芽型区别之处在于前者鼓室内听骨链周围有“类骨质”样散在高密度影。②耳内镜所见慢性化脓性中耳炎静止期鼓膜紧张部穿孔,鼓膜可有钙化斑;中耳胆脂瘤型则有上鼓室内陷或穿孔、后上象限穿孔、大穿孔、外耳道顶壁或后上壁下塌。结论 慢性化脓性中耳炎静止期及中耳胆脂瘤的术前CT及耳内镜评估,对病变性质、范围、程度及指导手术起重要作用。