CT evaluation of prosthetic ossicular reconstruction procedures: what the otologist needs to know.

Postoperative otologic evaluation of patients who have undergone ossicular reconstruction is often difficult. However, thin-section computed tomography (CT) can help determine the type of prosthesis used for reconstruction and adequately assess for complications that may be causing postoperative conductive hearing loss. A variety of prostheses may be used in ossicular reconstruction (eg, stapes prosthesis, incus interposition graft, Applebaum prosthesis, Black oval-top prosthesis, Richards centered prosthesis, Goldenberg prosthesis) and can usually be identified at CT by their shapes and locations. Several causes of prosthetic failure are readily demonstrated at CT, including recurrent cholesteatoma and otitis media, formation of granulation tissue or adhesions, and various mechanical problems (eg, subluxation, dislocation, extrusion, fracture, bending). Perilymphatic fistula can be difficult to identify at CT but may be suggested by the presence of pneumolabyrinth, unexplained middle ear effusion, or fluid accumulation within the mastoid air cells. The presence of soft tissue within the oval window niche 4-6 weeks following surgery may indicate poststapedectomy granuloma or fibrosis. Familiarity with the normal and abnormal CT appearances of ossicular prostheses will enable the radiologist to assist the otologist in identifying patients in whom revision surgery is most appropriate.     

Computerized tomography in cholesteatoma of the middle ear with intact tympanic membrane

The growth of a middle ear cholesteatoma behind a normal tympanic membrane is a rare though possible event. In such cases, CT may provide useful information for diagnosis. The results are presented of a CT study carried out on 14 patients affected with unilateral conductive hearing loss and with normal tympanic membrane. CT allowed the diagnosis of middle ear cholesteatoma to be made in all cases. All patients were treated with surgery: 8 of them underwent tympanoplasty and 6 explorative tympanotomy. While the diagnosis of cholesteatoma was confirmed in 13 patients, in 1 case tympanosclerosis was diagnosed. CT diagnosis of middle ear cholesteatoma is based on the demonstration of a low-density soft-tissue mass, in association with bone erosion or ossicular dislocation. The author emphasizes the difficulty of a CT diagnosis of cholesteatoma in the patients with middle ear soft-tissue masses in the absence of bone alterations.     

HRCT和MRI对慢性中耳炎的诊断价值

目的 探讨HRCT及MRI对慢性中耳炎的诊断价值。资料与方法 回顾性分析经病理及临床证实的72例慢性中耳炎的HRCT和MRI表现，并进行对比分析。结果 HRCT显示听小骨链破坏。移位（33/61），中耳乳突骨质破坏（33/61），乳突气房消失（54/61），鼓室及鼓窦黏膜增厚，积液（55/61），乙状窦，鼓室盖破坏及半规管瘘（4/61），HRCT也能显示鼓室内及外耳道异常软组织影，MRI不能显示岩骨细微的骨质结构。渗出性慢性中耳炎显示长T1长T2信号影（10/10）。肉芽肿型中耳炎显示为T1长T2信号影（4/6）或短T1长T2信号影（2/6），增强后明显强化，胆脂瘤型中耳炎表现为短T1长T2信号（7/11）或等T1长T2信号（4/11），增强后不强化或环形强化。结论 HRCT显示听小骨及乳突骨质结构较佳。对手术及听力恢复有指导意义。MRI则能确定软组织病变性质，可区别肉芽组织和胆脂瘤。     

CTVE对胆脂瘤型中耳炎听骨链病变的诊断价值

目的：探讨螺旋CT仿真内镜（CTVE）对胆脂瘤型中耳炎听骨链病变的诊断价值。方法：比较28耳胆脂瘤型慢性中耳炎听骨链的CTVE表现与临床手术所见。结果：CTVE显示的胆脂瘤型中耳炎听骨链破坏与手术所见基本相符，但对听骨链的细微病变价值有限，结论：CTVE是一种全新的多角度立体地观察听骨链结构的非侵入性影像手段。     

Is there a role for virtual otoscopy in the preoperative assessment of the ossicular chain in chronic suppurative otitis media? Comparison of HRCT and virtual otoscopy with surgical findings

The aim of this study was to assess the role of virtual otoscopy and 3D ossicular reconstruction in the preoperative assessment of the ossicles in chronic suppurative otitis media. Thirty three patients of chronic suppurative otitis media with conductive deafness (air–bone gap > 35 dB) were included in this prospective study. All patients underwent axial multidetector CT. The axial CT data set was utilized for multiplanar 2D reformations as well as virtual otoscopy (VO) and 3D reconstructions. The imaging findings on these two techniques were read independently by two radiologists with respect to different parts of the ossicular chain by using a three-point scoring system and were compared with surgical findings. Both imaging techniques had comparable accuracy for evaluation of larger ossicular parts. However, for evaluation of stapes superstructure, VO/3D images were more accurate (85.29%) than 2D images (76.97%). Assessment of the lenticular process and incudostapedial joint by HRCT and 2D reformatted images was not reliable (P > 0.1); however, significant correlation (P < 0.001) was present between VO/3D and the operative findings. Virtual otoscopy improves evaluation of the ossicular chain particularly that of smaller structures such as the lenticular process, incudostapedial joint and stapes superstructure which may influence decisions regarding planning of ossiculoplasty.     

听骨链螺旋CT三维重建技术及初步临床应用

目的探讨听骨链螺旋CT三维重建技术的临床应用及局限性.方法采用螺旋CT薄层扫描(层厚1.0mm),Pitch1.5,小视野(FOV=9.0cm),密集重建(间隔0.5mm).观察22例,其中10例正常,12例耳部病变患者,所有病例均采用表面遮盖法(SSD)行听骨链三维重建成像.正常及异常耳的观察阈值分别为-200～-500HU和100～300HU.结果10例正常耳听骨链重建能直观显示锤、砧骨的大小、形态及相互关系,砧镫关节呈"L”形,镫骨前后脚及底板显示欠佳.12例患者中,3例胆脂瘤型及1例肉芽肿型中耳炎患者,3D图像显示有不同程度听小骨破坏,与手术所见基本相符.1例肉芽肿型、2例单纯型中耳炎及2例颞骨骨折患者听骨链3D图像均显示正常.2例中耳畸形显示听骨链发育异常.1例神经鞘瘤病显示听小骨被肿瘤组织破坏.结论螺旋CT三维重建技术能很好显示正常及异常听骨链的立体影像,有利于中耳炎、中耳畸形及其它耳部病变的诊断.     

慢性中耳炎的HRCT诊断

目的探讨慢性中耳炎的HRCT特征、诊断及鉴别诊断.方法回顾性分析105例慢性中耳炎患者术前临床和HRCT检查资料,并与手术病理结果对照.结果36例胆脂瘤型中耳炎HRCT表现为鼓室或/及鼓窦内团块状软组织影和骨质改变,包括听骨硬化、移位、破坏,盾板破坏及中耳腔扩大,有的还伴有乙状窦、天盖、水平半规管的破坏.69例渗出肉芽型中耳炎HRCT表现多呈斑片状、条索状或网状软组织影,部分可见液平,听骨移位及破坏较轻.结论依据中耳腔内软组织影的分布、形态及骨质改变等特点,大多数慢性中耳炎可籍HRCT做出诊断或鉴别诊断.     

胆脂瘤型中耳炎的CT诊断

本文回顾性分析了经手术病理证实的４９耳胆脂瘤型中耳炎和８耳胆固醇性肉芽肿的临床和ＨＲＣＴ检查资料。中耳胆脂瘤的ＣＴ表现为：（１）鼓室、鼓窦内软组织影和骨质破坏；（２）听骨移位及破坏；（３）鼓膜增厚、内陷、穿孔；（４）严重者可破坏乙状窦板、天装置、半规管和面神经管等。笔者对后天性胆脂瘤的组织密度、颞骨各部位胆脂瘤的ＣＴ诊断，胆固醇肉芽肿的病理机制、临床和ＣＴ表现、与胆脂瘤的鉴别诊断等进行了探讨。     

中耳胆脂瘤--一个特征性CT征象

目的 :研究中耳胆脂瘤的 CT特征 ,提高对其 CT征象的认识。方法 :对手术证实的 14例慢性中耳炎和 14例中耳胆脂瘤的病人进行 HRCT扫描 ,着重观察盾板和上鼓室外侧壁骨质改变。对软组织病灶分布、形态 ,听骨破坏等也进行了分析、比较。结果 :胆脂瘤中 ,盾板破坏 12例 ,同时合并上鼓室外侧壁破坏 8例 ;慢性中耳炎肉芽肿型盾板侵蚀 1例 ,无上鼓室外侧壁破坏。结论 :盾板骨质破坏和上鼓室外侧壁破坏是松弛部胆脂瘤较特征性的 CT征象。软组织分布和形态、听骨破坏有辅助诊断价值。     

MSCT在胆脂瘤型中耳炎中的应用

目的:分析胆脂瘤型中耳炎的MSCT表现,探讨MSCT在临床的应用价值。方法:分析32例经手术、病理证实胆脂瘤型中耳炎的MSCT特征,及其对临床的指导作用。结果:胆脂瘤型中耳炎的MSCT表现有鼓室及鼓窦内软组织密度影;听小骨破坏;周围结构如盾板、半规管、面神经管可破坏,其中盾板常见。结论:MSCT可以清楚显示中耳胆脂瘤的部位、形态、听小骨及周围结构的破坏情况有助于明确诊断,为手术治疗提供依据。     

Diffusion-weighted MR imaging in postoperative follow-up: Reliability for detection of recurrent cholesteatoma

Introduction

Cholesteatoma is a progressively growing process that destroy the neighboring bony structures and treatment is surgical removal. Follow-up is important in the postoperative period, since further surgery is necessary if recurrence is present, but not if granulation tissue is detected. This study evaluates if diffusion-weighted MR imaging alone can be a reliable alternative to CT, without use of contrast agent for follow-up of postoperative patients in detecting recurrent cholesteatoma.

Materials and methods

26 consecutive patients with mastoidectomy reporting for routine follow-up CT after mastoidectomy were included in the study, if there was loss of middle ear aeration on CT examination. MR images were evaluated for loss of aeration and signal intensity changes on diffusion-weighted sequences. Surgical results were compared with imaging findings.

Results

Interpretation of MR images were parallel with the loss of aeration detected on CT for all 26 patients. Of the 26 patients examined, 14 were not evaluated as recurrent cholesteatoma and verified with surgery (NPV: 100%). Twelve patients were diagnosed as recurrent cholesteatoma and 11 were surgically diagnosed as recurrent cholesteatoma (PPV: 91.7%). Four of these 11 patients had loss of aeration size greater than the high signal intensity area on DWI, which were surgically confirmed as granulation tissue or fibrosis accompanying recurrent cholesteatoma.

Conclusion

Diffusion-weighted MR for suspected recurrent cholesteatoma is a valuable tool to cut costs and prevent unnecessary second-look surgeries. It has the potential to become the MR sequence of choice to differentiate recurrent cholesteatoma from other causes of loss of aeration in patients with mastoidectomy.     

肉芽肿型和胆脂瘤型中耳炎的X线平片与CT对照观察

目的:探讨CT和X线平片在诊断慢性中耳炎中的作用。方法:搜集经手术病理证实的肉芽肿型和胆脂瘤型中耳炎33例,术前同时行CT和X线平片检查,比较分析其CT和X线表现,并与手术结果对照。结果:33例中,肉芽肿型中耳炎6例,胆脂瘤型中耳炎2 7例,X线平片和CT发现乳突骨质破坏分别为18例和32例,两者差异有显著性意义(P<0. 0 5 ) ;鼓窦入口扩大分别为13例和2 0例,破坏区边缘硬化分别为10例和17例,两者之间差异均无显著性意义(P >0 .0 5 ) ;CT发现7例外耳道软组织病灶和2 4例听小骨破坏中的2 3例,而X线平征均不能显示。结论:X线平片可作为中耳炎的初选检查方法,CT是中耳炎的重要检查手段     

Congenital middle-ear deafness: CT study

Computed tomography (CT) was used to study 25 patients with congenital conductive hearing loss and normal external auditory canals. Deformities were subdivided according to ossicular, fenestral, and cholesteatomatous origin. Isolated ossicular deformities were found in 14 patients (five bilateral), cholesteatoma in eight, oval-window nondevelopment (with ossicular deformity) in one, and normal studies in two (congenital stapes fixation at the level of the annular ligament). Ossicular deformities may be subdivided into incudostapedial disconnections into incudostapedial disconnections (most common), malleoincudal fixations, and stapes fixations. Most are due to developmental anomaly of the first or second branchial arch. The stapes has a dual origin (second arch and otic capsule). A cholesteatoma is defined as congenital only if there is no history of otitis and the tympanic membrane is intact. In this series, six were in the middle ear proper, and two were within the attic beyond otoscopic view. Their CT appearance, with one exception, was essentially identical to that of acquired lesions.     

中耳胆脂瘤的HRCT诊断

目的 :探讨中耳胆脂瘤HRCT特征、诊断及鉴别诊断。材料和方法 :回顾性分析 66例中耳胆脂瘤患者术前临床和HRCT检查资料 ,并与手术病理结果对照。结果 :66例中耳胆脂瘤HRCT表现为鼓室 /鼓窦内团块状软组织影和骨质改变 ,包括听骨硬化、移位、破坏 ,盾板破坏及中耳腔扩大 ,有的还伴有乙状窦、天盖、面神经管及水平半规管的破坏。结论 :依据中耳腔内软组织影的分布、形态及骨质改变等特点 ,中耳胆脂瘤可通过HRCT做出诊断和鉴别诊断。     

Surgical treatment of chronic suppurative otitis media

The results of surgical treatment of chronic suppurative otitis media with or without cholesteatoma were presented in 708 patients over the period of ten years. Microtoilet of the ear and treatment of pathologic processes in the upper respiratory tract in the preoperative period the authors consider important for success in surgery. The best functional results were achieved with tympanoplasty bearing in mind adjustment of operative technic for each case depending on the nature and spreading of the process. The most frequent recurrences occurred in patients with cholesteatoma surgery (32%).     

Ossicular erosions in the dry ear: CT diagnosis

Erosions of the ossicular chain that occurred as a complication of noncholesteatomatous chronic otitis media were studied with computed tomography (CT) in 55 patients. The incus (particularly the long and lenticular processes) was the ossicle most commonly involved (50 cases). Coronal and axial CT sections were complementary in the diagnosis of these erosions. Fibrous replacement of the incudostapedial articulation was diagnosed in four cases on axial CT scans when an unusually wide joint was present.     

胆脂瘤型中耳炎的高分辨率CT诊断

目的　探讨胆脂瘤型中耳炎的高分辨率CT征象 ,提高对本病诊断的准确性。方法　回顾性研究经手术及病理证实的31例胆脂瘤型中耳炎患者的CT资料。结果　高分辨率CT能清楚地显示起源部位不同和大小不等的中耳胆脂瘤的软组织影填塞征象及其引起的中耳系统细微的骨质破坏征象。手术与CT诊断不同部位胆脂瘤的符合率达 93 .5 %～ 1 0 0 %。结论　高分辨率CT对于胆脂瘤型中耳炎的准确诊断具有很高的价值。     

先天性心脏病患儿分泌性中耳炎的螺旋CT诊断价值

目的评价螺旋CT对先天性心脏病患儿分泌性中耳炎的诊断价值。资料与方法回顾性分析我院2008-02～2010-10收治的先天性心脏病反复上呼吸道感染的残疾儿童46例78耳分泌性中耳炎的螺旋CT表现。结果 28例37耳有不同程度的乳突密度增高,气房减少,听小骨完整,周围骨质无破坏;21例41耳仅表现为乳突气房模糊。2例支气管扩张;6例唇腭裂;8例腺样体肥大;1例鼻中隔偏曲;38例伴不同程度的筛窦、上颌窦积液。结论螺旋CT可清晰显示中耳、乳突、鼻旁窦结构及腺样体肥大程度,对先天性心脏病患儿分泌性中耳炎的临床诊断有重要的指导价值。     

上鼓室开放同期鼓室成形术中残余听骨的再利用

目的观察上鼓室开放同期鼓室成形术中自体听骨及乳突皮质骨的利用效果及自体凝血块作为重建听骨链支撑材料的效果。方法对23耳局限性胆脂瘤型中耳炎行上鼓室开放及鼓室成形术,术中封闭鼓窦,开放上鼓室,术后随访6～24月。结果 23耳经纯音测听检查语言频率听力3耳比术前提高25 dB,7耳提高20 dB,7耳提高15 dB,6耳提高10 dB。未见胆脂瘤复发、鼓膜再穿孔或移植骨被排出。结论自体砧骨或乳突皮质骨是良好的听骨链重建材料,经过塑形完全可以再次应用到鼓室成形术中。自体血凝块加明胶海绵小碎块是取材方便的重建听骨链的支撑材料。封闭鼓窦及开放上鼓室有利于上鼓室上皮化。     

高分辨率CT显示听小骨能力的研究

目的 探讨高分辨率CT（HRCT）单侧密集骨重建技术对听小骨细微结构的显示能力及对疾病的诊断价值。方法：收集45人，81只耳的资料，全部病例行HRCT扫描，后进行单侧局部密集骨重建，观察轴冠位的正常及异常HRCT图像对听小骨（包括砧骨豆状突，砧镫关节，镫骨前后脚、脚板）的显示情况。结果：慢性中耳乳突炎31只，外耳道先天性闭锁伴中耳发育畸形2只，颞骨骨折波及中耳1只。HRCT密集骨重建，轴冠位结合扫描，能清晰显示听小骨炎症的微小破坏，骨折等病变；结合中耳仿真内镜可清晰地显示发育畸形的听小骨。结论：HRCT能清晰，准确地显示听小骨细微结构。优于传统的CT图像，可为临床诊断和治疗提供可靠的依据。