鼻腔及鼻窦解剖结构在CT仿真内窥镜下的显示

目的 :探讨鼻腔及鼻窦解剖结构在螺旋CT仿真内窥镜 (VE)和常规冠状位扫描图像上的显示特点。方法 :经过螺旋CT冠状位扫描或轴位扫描的原始数据被传输到工作站上 ,然后利用NAVIGATOR软件行VE成像 ,调节阈值 ,观察窦口 鼻道复合体等解剖结构 ,测量必要的参数。结果 :鼻甲、鼻道和窦口 鼻道复合体等结构在仿真内窥镜下能更好地被显示 ,骨性解剖显示尤其清晰 ,VE和冠扫两种方法的显示效果有显著性差异(P <0 .0 5 )。因VE显示级别较高 (秩和大 ) ,所以VE的显示效果优于冠扫。钩突、筛泡、半月裂和筛漏斗在VE和冠扫图像上的显示率基本一致 ,额隐窝、鼻额管的显示率较低。结论 :VE显示在评价鼻腔及鼻窦解剖结构方面具有重要的价值 ,有助于放射科及耳鼻咽喉科医师更好地认识其特点     

Sensitivity and specificity of nasal flexible fiberoptic endoscopy in the diagnosis of adenoid hypertrophy in children

OBJECTIVE: To evaluate nasal flexible fiberoptic endoscopy as a diagnostic test of adenoid hypertrophy in children with nasal obstruction. METHODS: One hundred and thirty consecutive children aged 2-12 years were examined from May to October 2005. A questionnaire answered by parents or guardians was used to obtain a symptom score. Adenoid size was measured on radiographs of the nasal cavity using the Cohen and Konak method, and by nasal flexible fiberoptic endoscopy using the Wornald and Prescott classification. The criterion standard was the adenoid size demonstrated on radiograph. RESULTS: The sensitivity of nasal flexible fiberoptic endoscopy was 92% (95% CI, 0.90-0.93), and specificity, 71% (95% CI, 0.70-0.72). The area under the ROC curve was 0.83 (95% CI, 0.76-0.90) at a p<0.001 level of significance. Kappa values were 0.94 (p<0.001) for interobserver agreement, 0.95 (p<0.001) for intraobserver agreement, and 0.54 (p<0.001) for agreement between tests. CONCLUSIONS: Results suggest that nasal flexible fiberoptic endoscopy is a highly accurate diagnostic method. This examination can be performed easily in cooperative children; it is safe, objective and dynamic, and helps to establish diagnoses in difficult cases.     

纤维喉镜与模拟内镜技术对阻塞性睡眠呼吸暂停低通气综合征的诊断价值

目的:比较纤维喉镜与模拟内镜技术在阻塞性睡眠呼吸暂停低通气综合征(OSAHS)诊断中的作用和各自的优缺点;进一步探讨上呼吸道在阻塞通气过程中的变化特点.方法:我们对21例经睡眠监测确诊为OSAHS的患者行电子纤维喉镜检查,并行螺旋CT扫描后经软件处理.获得仿真上呼吸道图像.检查在清醒和睡眠2种状态下进行.测量软腭平面、悬雍垂平面、舌后平面和会厌平面的前后径和左右径.结果:纤维喉镜与仿真上呼吸道图像在上呼吸道的4个平面的测量上均差异有统计学意义;在清醒和睡眠状态下,软腭后区前后径的变化差异无统计学意义,其左右径差异有统计学意义.结论:清醒与睡眠状态下,上呼吸道的腔径有明显不同;腔径的变化以左右径变化为主;纤维喉镜在上呼吸道的动态观察中有很重要的诊断价值;仿真上呼吸道图像能够真实的显示上呼吸道狭窄的部位和程度;结合原始的二维图像可提供解剖结构和病理变化的相关信息.     

Virtual endoscopy imaging of the middle ear cavity and ossicles

Ten cadaver temporal bone blocks were studied with high-resolution computed tomography (HRCT) in order to produce topographic images, which are more informative than ordinary CT slices. Virtual endoscopic images were produced with separate, commercially available software, paying attention to the middle ear cavity and ossicles. Four major viewing locations for virtual endoscopy (the ear canal, hypotympanum, attic and eustachian tube) developed images acceptably. The malleus and incus were visualized properly. Small structures such as the lenticular process and the stapes sometimes failed to have good imaging. The eustachian tube and attic virtual views, which are usually not receptive to ordinary endoscopy, gave proper visualization of middle ear structures. Even the smallest structure, the stapes, can produce a virtual image.Virtual endoscopic images, or topographic images, of the middle ear and ossicles contribute to the understanding of the anatomy of the middle ear, thus enhancing the chances for successful surgery. Received: 2 January 2001 / Accepted: 9 July 2001     

慢性中耳炎听骨链病变虚拟耳镜观察

目的 探讨虚拟耳镜对慢性中耳炎听骨链病变的评估作用。方法 慢性中耳炎95耳（82例），均经高分辨螺旋CT轴位、冠状位颞骨扫描，应用虚拟耳镜软件包进行图像三维重建。将术前虚拟耳镜与手术探查结果进行对比分析。结果 95耳慢性中耳炎术前经虚拟耳镜观察，提示86耳听骨链不同程度的破坏．术中证实67耳锤、砧骨破坏，15耳镫骨头或镫骨上结构缺失，4耳听骨链完整连续。结论 虚拟耳镜是术前评估中耳炎听骨链病变的可靠的影像学手段。     

Correlations between virtual endoscopy and otoendoscopy of the retrotympanum

The aim of this study was to examine the anatomical landmarks of the retrotympanum using two different techniques, virtual endoscopy (VE) and fiberoptic endoscopy, and to correlate the results furnished by the two methods. Ten otosclerotic patients who were due to undergo stapedectomy were scanned using high-resolution spiral CT. Selected CT datasets were processed with Navigator 2.0 software to obtain virtual endoscopic views of the retrotympanum. Subsequently, during the surgical procedure, fiberoptic endoscopy was performed with 2.7-mm 0 degrees and 30 degrees rigid endoscopes. The ability of the two imaging methods to identify specific anatomical structures was then compared. In all cases the pyramidal eminence, pyramidal crest and sinus tympani were clearly identified in both VE images and otoendoscopy recordings, while fiberoptic endoscopy seemed to be less satisfactory than VE for studying the facial sinus, sinus of Proctor and fossula of Grivot. The two techniques proved to be equally sensitive for visualizing the ponticulus and subiculum, while the stapedius tendon could be visualized only by means of fiberoptic endoscopy. Overall, VE imaging appears promising for rendering important anatomical details of the retrotympanum, allowing identification of osseous landmarks and exploring recesses that are difficult to visualize via otoendoscopy.     

Virtual endoscopy of the middle and inner ear with spiral computed tomography

OBJECTIVE: To evaluate the inner anatomy of the auditory apparatus by means of virtual endoscopy of spiral computed tomography (CT) data sets. BACKGROUND: Virtual endoscopy permits simulation of the fiberoptic endoscopy perspective by processing CT or magnetic resonance images. METHODS: Seven formalin-fixed specimens of human mastoid were scanned with spiral CT with the following protocol: beam collimation 1 mm, pitch ratio 1, reconstruction spacing 0.2 to 0.5 mm, field of view 90 mm. For the generation of endoscopic views of the auditory spaces, the axial images were processed with Navigator software 2.0 running on UltraSparc I workstation. RESULTS: Virtual endoscopy allowed the demonstration of the external auditory canal, the head and handle of the malleus, the stapes and incudostapedial articulation, the corpus, the long process of the incus with its lenticular process and the short limb, the malleoincudal articulation, the rounded promontory, the round and oval windows, and Prussak's space. From inside the basal turn of the cochlea, virtual endoscopy showed the orifices of the fenestrae cochlea and vestibuli, the origin of the lateral and the anterior semicircular canals, and the basal turn of cochlea. The optimal perspectives that allowed demonstration of the anatomical details of the middle and inner ear are described. CONCLUSION: Virtual endoscopy allows the generation of inner views of the auditory spaces. This new method of image processing can be proposed as an integrative tool of spiral CT imaging.     

Virtual Endoscopy of the Paranasal Sinuses Using Perspective Volume Rendered Helical Sinus Computed Tomography

Our goal was to use three-dimensional information obtained from helical computed tomographic (CT) data to explore and evaluate the nasal cavity, nasopharynx, and paranasal sinuses by simulated virtual endoscopy (VE). This was done by utilizing a new image reconstruction method known as perspective volume rendering (PVR). Thin-section helical CT of the nasal cavity, nasopharynx, and paranasal sinuses was performed on a conventional CT scanner. The data were transferred to a workstation to create views similar to those seen with endoscopy. Additional views not normally accessible by conventional endoscopy were generated. Key perspectives were selected, and a video “flight” model was choreographed and synthesized through the nasal cavity and sinuses based on the CT data. VE allows evaluation of the nasal cavity, nasopharynx, and paranasal sinuses with appreciation of the relationships of these spatially complex structures. In addition, this technique allows structural visualization with unconventional angles, perspectives, and locations not conventionally accessible. Although biopsies, cultures, and lavages routinely done with endoscopy cannot be performed with VE, this technique holds promise for improving the diagnostic evaluation of the nasal cavity, the nasopharynx, and the paranasal sinuses. The unconventional visual perspectives and very low morbidity may complement many applications of simple diagnostic endoscopy.     

Detection of perilymphatic fistula in labyrinthine windows by virtual endoscopy and variation of reconstruction thresholds on CT scan

Abstract

Background: Perilymphatic fistula (PLF) is a breach in a labyrinthine window. The opening might decrease the radiological density of the window.

Aims/objectives: To evaluate the radiological density of the labyrinthine windows by virtual endoscopy on CT scan.

Materials and methods: This prospective study included 47 adult patients with PLF and 98 control patients. Diagnosis of PLF was based on a composite radio clinical score and/or intra operative visualization of the fistula and/or resolution of the symptoms after surgery. On routine CT-scan, labyrinthine windows were examined by virtual endoscopy. The reconstruction threshold was gradually increased until a virtual opening appeared (opening threshold [OT]) and compared to the contralateral window (OT difference).

Results: The OT difference was higher in patients than in controls (60.2?±?10.36 (SEM), n?=?47 versus 28.0?±?2.29 Hounsfield units (HUs), n?=?98, p?<?.01 unpaired t-test). A ROC analysis showed that at an OT difference of 31.5 UH had a sensitivity of 75% and a specificity of 75% for the PLF diagnosis.

Conclusions: CT-scan virtual endoscopy and threshold variation provided high specificity and sensitivity in the PLF diagnosis.

Significance: This post processing of radiological data appears to enhance the diagnostic value of CT scan.     

鼻内窥镜下射频热凝治疗鼻腔血管瘤

目的：探讨鼻内窥镜下射频热凝治疗鼻腔血管瘤的优越性。方法：将鼻内窥镜与射频联合应用治疗鼻腕血管瘤患者１５例。结果：１５例均一次成功摘除血管瘤,术中出血少,无并发症发生,随访０．５￣４年无复发。结论：鼻内窥镜下射频热凝治疗鼻腔血管瘤,具有视野清晰、出血少、手术安全彻底、患者痛苦少及不遗留面部瘢痕等优点。     

CT联合鼻内镜对真菌性上颌窦炎的诊断价值

目的探讨CT联合鼻内镜检查对真菌性上颌窦炎的诊断价值。方法选取2015年8月~2017年12月我院收治的CT初步诊断为真菌性上颌窦炎的患者184例,再结合鼻内镜检查诊断真菌性上颌窦炎,以术后病理结果为金标准分别计算单纯CT、CT联合鼻内镜诊断真菌性上颌窦炎的准确率,使用SPSS 16.0软件进行统计学分析,比较两者的准确率是否具有统计学差异。结果单纯CT诊断真菌性上颌窦炎的准确率为75.8%,CT联合鼻内镜检查诊断真菌性上颌窦炎的准确率为93.0%,CT联合鼻内镜检查诊断真菌性上颌窦炎的准确率比单纯CT检查高17.2%,两者之间的准确率差异具有统计学意义（P＜0.05）。结论CT对于真菌性上颌窦炎的诊断具有重大价值,CT与鼻内镜联合诊断提高了真菌性上颌窦炎诊断的准确率,对临床诊治具有更大的指导意义。     

先天性外耳道闭锁听骨链的虚拟耳镜观察

目的：探讨虚拟耳镜对先天性外耳道闭锁听骨链畸形术前评估的作用。方法：23例（28耳）先天性外耳道闭锁、中耳畸形患者,经高分辨率螺旋CT轴位、冠状位颞骨扫描,应用仿真内镜软件行图像三维重建。术前虚拟耳镜结果与手术探查结果进行对比分析。结果：28耳外耳道闭锁、中耳畸形,虚拟耳镜提示25耳听小骨发育不全,3耳狭小鼓室未见听骨。24耳行手术治疗,术中发现锤、砧骨发育不全19耳,镫骨畸形11耳,镫骨缺失3耳,前庭窗闭锁1耳。术前虚拟耳镜观察与术中探查符合率为100％。结论：虚拟耳镜为先天性外耳道闭锁听骨链畸形的术前评估提供了可靠的影像学信息。     

鼻内镜手术治疗鼻腔及鼻窦内翻性乳头状瘤的疗效观察

目的：观察鼻内镜手术治疗鼻腔及鼻窦内翻性乳头状瘤的疗效。方法：病理和临床诊断为鼻腔及鼻窦内翻性乳头状瘤16例,术前做鼻内镜检查及鼻窦CT扫描,全身麻醉鼻内镜下行鼻腔及鼻窦内翻性乳头状瘤切除术。结果：术后随访1～2年,16例患者术后复发2例。结论：鼻内镜手术是治疗Krouse Ⅰ～Ⅱ级鼻腔及鼻窦内翻性乳头状瘤的一种较好的方法,此方法的优点为视野清楚、创伤少、出血量少、复发率低、避免了面部切口。     

The role of nasal endoscopy in outpatient management

The data from 140 consecutive patients who had undergone computerized tomography (CT) as part of their investigation for nasal symptoms, and who had been examined by one surgeon, were retrospectively reviewed. The history, rhinoscopic findings, endoscopic findings, changes on CT and final diagnosis were noted. Endoscopy was found to identify more disease than rhinoscopy (85% versus 74%); and a similar picture was seen when combining history with either endoscopy or rhinoscopy. Endoscopic examination was found to have a sensitivity of 84% and a specificity of 92%. In 25 (18%) patients endoscopy contributed positively towards a correct diagnosis, but in 11 (8.0%) there were false positive findings. CT findings led to a re-evaluation of the diagnosis and alteration of management of these 11 individuals who had false positive endoscopic findings. History alone led to an accurate diagnosis in 84% of patients with inflammatory nasal conditions. The role of the endoscope is best considered as ‘fine tuning’; and supplementary to a detailed history.     

Evaluation of airway obstruction using virtual endoscopy

OBJECTIVES: This study examines the use of virtual endoscopy (VE) in the evaluation of patients with upper airway obstruction. The utility of VE compared with actual endoscopy was investigated with respect to accuracy of diagnosis and reproduction of endoscopic images. STUDY DESIGN: A random cohort of 30 patients with various causes of airway obstruction was examined. METHODS: The computed tomography (CT) data were reconstructed using a proprietary VE software program, FreeFlight, blind to the actual endoscopic findings. The cause of obstruction was identified and compared with actual endoscopic findings. This included 21 patients with airway stenoses, 8 patients with laryngotracheomalacia, 3 tracheal tumors, 2 glottic webs, 5 patients with innominate artery compression, 2 tracheal granulomas, and 7 patients with impaired true vocal cord mobility. RESULTS: Virtual endoscopic evaluation was accurate in assessing stenosis width and length of fixed airway lesions. Correlation of stenosis shape and contour between actual endoscopy and VE was excellent. The stenosis-to-lumen ratios were compared between VE and actual endoscopy and were found to be within 10% (SD = 8). However, virtual endoscopic evaluation could not illustrate one of the glottic webs, half of the cases of tracheomalacia, or any of the cases of impaired true vocal cord mobility. CONCLUSIONS: Virtual endoscopy was not as sensitive as actual endoscopy in detecting the cause of airway obstruction that was based on dynamic movement. However, VE was excellent for the measurement and definition of fixed airway lesions.     

Detection of labyrinthine fistulas in human temporal bone by virtual endoscopy and density threshold variation on computed tomographic scan

OBJECTIVE: To assess the sensitivity of the routine computed tomographic (CT) scan of the temporal bone coupled to a virtual endoscopy, with density threshold variation, in detecting small fistulas in human temporal bone specimens. DESIGN: Single-blind, before-after trial. SETTING: This study was carried out in a research laboratory in collaboration with a radiology department. PATIENTS: Five human adult temporal bone specimens were included. INTERVENTIONS: The fistulas were created with calibrated burrs (0.3, 0.5, and 0.8 mm) in the 3 semicircular canals and in the promontory of 3 temporal bones. Two other temporal bones served as controls. All bones underwent CT scan (1-mm section thickness) before and after dissection. Three-dimensional images were obtained from CT scan native axial views at different density reconstruction thresholds. The virtual endoscope was placed in the middle ear cavity looking to the inner ear wall. The threshold at which a bony defect appeared on virtual endoscopic images (opening threshold in Hounsfield units [H]) was noted for each location. MAIN OUTCOME MEASURES: Opening thresholds before and after dissection. RESULTS: On standard axial views, fistulas smaller than 0.5 mm were not visualized. By virtual endoscopy, all fistulas could be visualized. The opening threshold decreased after fistula creation in the semicircular canals (1244 +/- 50.5 H [n = 36] vs 778 +/- 52.4 H [n = 34]; P<.001; 1-way analysis of variance and Dunnett multiple comparisons posttest) and in the promontory (1541 +/- 37.8 H [n = 12] vs 1334 +/- 35.1 H [n = 8]; P<.001). The opening thresholds in the control specimens remained unchanged after dissection. CONCLUSION: Virtual endoscopy with variation of reconstruction threshold allows the detection of small labyrinthine fistulas with diameters of 0.3 mm or smaller.     

Correlations Between Virtual Endoscopy and Otoendoscopy of the Retrotympanum

The aim of this study was to examine the anatomical landmarks of the retrotympanum using two different techniques, virtual endoscopy (VE) and fiberoptic endoscopy, and to correlate the results furnished by the two methods. Ten otosclerotic patients who were due to undergo stapedectomy were scanned using high-resolution spiral CT. Selected CT datasets were processed with Navigator 2.0 software to obtain virtual endoscopic views of the retrotympanum. Subsequently, during the surgical procedure, fiberoptic endoscopy was performed with 2.7-mm 0° and 30° rigid endoscopes. The ability of the two imaging methods to identify specific anatomical structures was then compared. In all cases the pyramidal eminence, pyramidal crest and sinus tympani were clearly identified in both VE images and otoendoscopy recordings, while fiberoptic endoscopy seemed to be less satisfactory than VE for studying the facial sinus, sinus of Proctor and fossula of Grivot. The two techniques proved to be equally sensitive for visualizing the ponticulus and subiculum, while the stapedius tendon could be visualized only by means of fiberoptic endoscopy. Overall, VE imaging appears promising for rendering important anatomical details of the retrotympanum, allowing identification of osseous landmarks and exploring recesses that are difficult to visualize via otoendoscopy.     

Head and neck computed tomography virtual endoscopy: evaluation of a new imaging technique.

OBJECTIVE: To evaluate a new radiographic imaging technique: computed tomography virtual endoscopy (CTVE) for head and neck tumors. STUDY DESIGN: Twenty-one patients presenting with head and neck masses who underwent axial computed tomography (CT) scan with contrast were evaluated by CTVE. Comparisons were made with video-recorded images and operative records to evaluate the potential utility of this new imaging technique. METHODS: Twenty-one patients with aerodigestive head and neck tumors were evaluated by CTVE. One patient had a nasal cylindrical cell papilloma; the remainder, squamous cell carcinomas distributed throughout the upper aerodigestive tract. Patients underwent complete head and neck examination, flexible laryngoscopy, axial CT with contrast, CTVE, and in most cases, operative endoscopy. Available clinical and radiographic evaluations were compared and correlated to CTVE findings. RESULTS: CTVE accurately demonstrated abnormalities caused by intraluminal tumor, but where there was apposition of normal tissue against tumor, inaccurate depictions of surface contour occurred. Contour resolution was limited, and mucosal irregularity could not be defined. There was very good overall correlation between virtual images, flexible laryngoscopic findings, rigid endoscopy, and operative evaluation in cases where oncological resections were performed. CTVE appears to be most accurate in evaluation of subglottic and nasopharyngeal anatomy in our series of patients. CONCLUSION: CTVE is a new radiographic technique that provides surface-contour details. The technique is undergoing rapid technical evolution, and although the image quality is limited in situations where there is apposition of tissue folds, there are a number of potential applications for this new imaging technique.     

Comparison of virtual and conventional endoscopy of nose and paranasal sinuses

We compared computed tomographic virtual rhinosinus endoscopy (VRS) and conventional fiberoptic endoscopy (FE) for the detection of inflammatory-obstructive rhinosinusal disease. We recruited 158 patients; 100 (group A) had inflammatory-obstructive rhinosinus disease, and 58 (group B) had a history of rhinosinus surgery. All patients underwent VRS within 2 to 6 hours of FE, and VRS was able to demonstrate the anatomic details of the nasal fossa and rhinopharynx with a high correspondence to FE. A satisfying representation of anatomic detail was found in both groups A and B. The VRS was able to visualize invasiveness of the endosinusal cavities, which was not accessible to FE. The VRS is a fast, relatively easy, and noninvasive technique that could be integrated into FE or used as an alternative when FE is unfeasible. Because of the ability to explore the sinus cavity, we suggest that virtual rhinosinusoscopy should be considered as the appropriate term, instead of virtual rhinoscopy.     

Is virtual endoscopy of the middle ear useful?

Virtual endoscopy is a relatively new imaging technology in otology, and therefore data on its efficacy in clinical situations are limited. We conducted a prospective study to evaluate the clinical relevance of radiologic diagnoses based on virtual endoscopy of the middle ear. Our patient population was made up of 30 adults who were scheduled to undergo surgery to correct conductive hearing loss of unknown etiology. Virtual endoscopy was performed on three-dimensional images that were constructed from images obtained with conventional two-dimensional computed tomography (CT). Findings on virtual endoscopy were then compared with the subsequent surgical findings. Virtual endoscopy suggested a middle ear pathology in 19 patients and a normal middle ear in 11 patients. Postoperatively, we found that the virtual diagnoses correlated moderately well with the surgical findings in the group of patients with predicted pathology; 13 of these 19 patients were found to have middle ear problems such as ossicular chain anomalies, otosclerosis, and cholesteatoma (positive predictive value: 68%). However, among the 11 patients whose middle ear structures were radiologically predicted to be normal, only 2 had negative middle ear findings on surgical exploration; of the remaining 9 patients, 8 had otosclerosis and 1 had malleus fixation (negative predictive value: 18%). Thus, the sensitivity and specificity of virtual endoscopy were 59 and 25%, respectively. Virtual endoscopy provides images from a surgeon's perspective, and so it has the potential to be useful in the preoperative evaluation of the middle ear cavity. With ongoing advancements in computer systems and imaging techniques, the cost, reliability, and efficacy of virtual endoscopy may improve. However, further clinical validation and cost-benefit analysis are required before we can determine if it has any additional advantages over conventional two-dimensional CT.