Vascular anomalies, sutures and small canals of the temporal bone on axial CT

PURPOSE: Subtle bony structures, small canals and fine sutures cause sometimes problems in the analysis of CTs of the temporal bone. The aim of this study was: to analyze the visibility of subtle structures and to estimate the incidence of vascular anomalies. PATIENTS AND METHOD: We retrospectively analyzed axial scans of 223 high-resolution CTs of the temporal bone obtained as single slice or spiral CT with 1mm slice thickness. All CTs had clinical indications. Two experienced radiologists studied CTs regarding the visibility of the fine sutures, fissures and small canals and the occurrence of vascular anomalies. RESULTS: The following structures were seen commonly: sphenosquamosal suture (76%), arcuate artery canal (93%), vestibular aqueduct (89%), mastoid emissary vein (82%), singular canal (56%). Not so commonly were observed: tympanosquamosal suture (31%), mastoid canaliculus (28%), lateral sigmoid sinus (28%), petrotympanic fissure (24%), tympanomastoid suture (10%). Seldom we identified: the inferior tympanic canaliculus (6%), high jugular bulb (6%), anterior sigmoid sinus (5%), dehiscent internal carotid artery canal (2%), persistent petrosquamosal sinus (1%), dehiscent jugular bulb (1%). Persistent stapedial artery, aberrant internal carotid artery, dehiscent jugular bulb, high jugular bulb with diverticulum, anterior and dehiscent sigmoid sinus were detected in below 1% of the analyzed temporal bones. The frequency of asymmetry of the jugular foramen, which varied between 3% and 42%, depended on different criterions of size. CONCLUSION: A profound knowledge of normal anatomy and anomalies of the temporal bone avoids misinterpretation as pathological lesions and iatrogenic bleedings.     

Dehiscence of the jugular bulb and vestibular aqueduct: findings on 200 consecutive temporal bone computed tomography scans

OBJECTIVE: To determine the incidence of dehiscence between the vestibular aqueduct and the jugular bulb on computed tomography (CT) scans and assess its implication as a cause of dizziness or hearing loss. METHODS: Two hundred temporal bone CT scans were evaluated for the prevalence of dehiscence between the jugular bulb and vestibular aqueduct. Correlation of the imaging findings and clinical data was performed. RESULTS: A total of 11.5% of patients had dehiscence of the jugular bulb with the vestibular aqueduct; 75% of these cases occurred on the right side and in the setting of a high jugular bulb. Nine (39.1%) of 23 patients with dehiscence had dizziness, and 11 (47.8%) had hearing loss. The correlation between the incidence of dizziness, hearing loss, and dehiscence was not significant. CONCLUSION: The incidence of a dehiscent jugular bulb with a vestibular aqueduct is 11.5%. The prevalences of vertigo and hearing loss associated with this finding are 39.1% and 47.8%, respectively. The depiction of dehiscent jugular bulb-vestibular aqueduct should be considered with caution as the sole cause of symptoms.     

耳鸣患者颞骨异常的CT及MRI研究

目的 采用HRCT和MRI对耳鸣患者颞骨进行检查,探讨其异常发生率及最佳扫描方案.方法 回顾性分析1015例耳鸣患者的HRCT和MRI资料.搏动性耳鸣145例,142例行HRCT,7例行MRI,其中4例同时行HRCT和MRI,仅行平扫HRCT者67例,仅行增强HRCT者71例.非搏动性耳鸣870例,650例行HRCT,267例行MRI,其中47例同时行HRCT和MRI,仅行平扫HRCT者598例,仅行增强HRCT者5例.分析颞骨异常阳性率及构成比,比较不同影像学检查方法和序列对颞骨异常的显示效果.采用χ2检验对数据进行组间分析.结果 1015例中显示病变者767例(75.57%).常见颞骨异常发生率分别为:颈静脉窝高位414例(40.79%);乙状窦异常387例(38.13%);中耳乳突炎148例(14.58%);中颅窝低位70例(6.90%).平扫HRCT对颈静脉窝高位显示阳性率最高(365/665,54.89%);增强HRCT对乙状窦异常显示的阳性率最高(56/76,73.68%).在搏动性耳鸣患者中,乙状窦异常发生率最高(96/145,66.21%),且其发生率明显高于非搏动性耳鸣患者(291/870,33.45%;χ2=56.537,P＜0.01).真稳态进动快速成像(FIESTA)序列显示内耳道内血管袢影最佳(42/42,100%).结论 颈静脉窝高位和乙状窦异常是耳鸣患者最常见的颢骨影像异常.搏动性耳鸣首选增强HRCT,非搏动性耳鸣首选平扫HRCT,内耳道内血管显示首选MR FIESTA序列.

Abstract：

Objective To study high resolution CT (HRCT) and MRI findings of temporal bone anomaly in patients with tinnitus and identify the optimal examination method in the detection of the anomaly. Methods The HRCT and MRI data were analyzed retrospectively in 1015 patients including 145 patients with pulsatile tinnitus (PT) and 870 patients with nonpulsatile tinnitus (NPT). The positive rates of HRCT and MRI in the identification of temporal bone anomaly were analyzed and the efficiency of various examination methods was compared in revealing the anomaly. Data were tested by Chi-square test analysis. Results Among 1015 patients, anomaly was seen in 767 cases (75.57%). High jugular bulb was found in 414 patients, accounting for 40. 79%. Sigmoid sinus anomaly was detected in 387 patients (38. 13%), while otitis media was found in 148 cases (14. 58%), and low middle cranial fossa in 70 cases (6. 90%). The positive rate of HRCT in the detection of high jugular bulb was 54. 89% (365/665), which was significantly higher than those of other methods (P ＜ 0. 05). The positive rate of enhanced HRCT in showing sigmoid sinus anomaly was 73.68% (56/76), which was significantly higher than those of other methods(P ＜0. 05). Sigmoid sinus anomaly was the most frequent finding in patients with PT, accounting for 66. 21% (96/145). The incidence of sigmoid sinus anomaly was higher in PT than in NPT (291/870,33.45% ;χ2 =56. 537 ,P ＜0. 01). The fast imaging employing steady-state acquisition (FIESTA) sequence was the best examination method in displaying the vessel within the internal auditory canal (42/42,100%).Conclusions High jugular bulb and sigmoid sinus anomaly were the most frequent abnormal findings of temporal bone in patients with tinnitus. Enhanced HRCT was the choice of modality in patients with PT.Plain HRCT was recommended for NPT. FIESTA sequence was the best in the evaluation of the vessel within the internal auditory canal.     

The jugular bulb diverticulum. A radioanatomic investigation

Two hundred and forty-five temporal bone specimens were examined radiographically. Subsequently the topographic relationship between the jugular fossa and surrounding structures was evaluated in plastic casts of the specimens. Fifty-eight casts showed a high jugular fossa and in 17 a jugular bulb diverticulum was found. A diverticulum is regarded as an anomaly of the high jugular bulb and presumably has a potential for expansion. Most frequently a diverticulum was directed medially into the space between the internal acoustic meatus, the vestibular aqueduct and the posterior cranial fossa. Seven diverticula reached the level of the internal acoustic meatus. Encroachment upon the vestibular aqueduct was seen in 4 casts and both the internal acoustic meatus and the cochlear aqueduct were very close to the diverticulum. A few diverticula were directed postero-laterally close to the facial canal and the stapedius muscle. The investigation was supplemented with a selected clinical material of radiographs of temporal bones with high fossae. The results corresponded to those of the experimental investigation. The jugular bulb diverticulum is a relatively common feature and should be regarded as an anomaly with a potential to give rise to clinical symptoms consequent to its intrusion upon surrounding structures.     

Direct sagittal CT in the evaluation of temporal bone disease

The human temporal bone is an extremely complex structure. Direct axial and coronal CT sections are quite satisfactory for imaging the anatomy of the temporal bone; however, many relationships of the normal and pathologic anatomic detail of the temporal bone are better seen with direct sagittal CT sections. The sagittal projection is of interest to surgeons, as it has the advantage of following the plane of surgical approach. This article describes the advantages of using direct sagittal sections for studying various diseases of the temporal bone. The CT sections were obtained with the aid of a new head holder added to our GE CT 9800 scanner. The direct sagittal projection was found to be extremely useful for evaluating diseases involving the vertical segment of the facial nerve canal, vestibular aqueduct, tegmen tympani, sigmoid sinus plate, sinodural angle, carotid canal, jugular fossa, external auditory canal, middle ear cavity, infra- and supralabyrinthine air cells, and temporomandibular joint.     

CT arteriography and venography in pulsatile tinnitus: preliminary results

BACKGROUND AND PURPOSE: Pulsatile tinnitus (PT), a common disorder, can be caused by a variety of otologic and vascular lesions. Various imaging modalities, including CT, MR imaging and angiography, and conventional angiography, have been used in the assessment of PT. Ideally, a single imaging study to evaluate for the largest variety of etiologies would be optimal. In our study, we examine the potential for CT arteriography and venography (CTA/V) in the evaluation of PT. METHODS: Sixteen patients with PT were prospectively evaluated by an otolaryngologist, had a normal otologic examination, and were referred for a CTA/V. All examinations were performed on a 16-section multidetector CT. The carotid bifurcations, internal carotid artery course, transverse and sigmoid sinuses, jugular foramen, internal jugular vein, sella turcica, and temporal bones were evaluated. RESULTS: Seven of the 16 patients had lesions on CTA/V that could account for their PT. Examples of pathologic conditions in the series included a significantly dominant venous system, a venous diverticulum with stricture, and a transverse sinus stenosis. CONCLUSIONS: Preliminary findings indicate that CTA/V can be a valuable imaging tool in the assessment of PT. With this technique, arterial, venous, middle, and inner ear causes of PT can be excluded.     

Pulsatile tinnitus and imaging diagnosis. A case report

Tinnitus is the perception of sound in one or both ears when no external noise exists to cause that perception. It can be otological, neurological, drug-related, traumatic, due to exposure to high decibel levels, or associated with a vascular abnormality—the latter usually causing pulsatile tinnitus. We present the diagnostic image of a patient with pulsatile tinnitus with terminal plate dehiscence of the jugular bulb and review the diagnostic workup. Jugular bulb dehiscence is a venous variant that consists of an upper and lateral extension of the jugular bulb into the middle ear through a dehiscent sigmoid plate. It is the most common vascular anatomical variant of the petrous portion of the temporal bone. Imaging studies are essential for establishing a diagnosis and defining possible anatomical variants.     

Preoperative evaluation of the congenital aural atresia on computed tomography; an analysis of the severity of the deformity of the middle ear and mastoid

OBJECTIVE: To compare the development of temporal bone in normal and atretic ears and to assess some radiological landmarks that could be important in the hearing restoration interventions in such patients. MATERIAL AND METHODS: Thirty-five patients with 40 atretic external ears were evaluated with temporal bone CT and compared to a control group of 40 normal ears retrospectively. Using comparable slice levels in all patients, the course and the caliper of the facial canal, the surface area of the incus and malleus, the level of mastoid aeration, the location and anteroposterior diameters of the jugular bulb and sigmoid sinus, the direction and the caliber of the tympanic bony part of the Eustachian tube, area of the middle ear cavity, distance from facial nerve to incudomalleolar joint, to the vestibule and to the jugular bulb were included in the assessment. Non-parametric and parametric statistical tests were used for comparison. RESULTS: In atretic ears middle ear sectional area was found to be smaller at the equivalent plane as compared to control subjects (mean area index: 19.3mm(2) versus 47.4mm(2)). Mastoid aeration was low in general and the ossicles in the atretic ears were hypoplastic (mean ossicular sectional area: 8.3mm(2) versus 11 mm(2)). The distance from the jugular bulb to the facial nerve was significantly lower (mean: 6.2mm versus 6.8mm) (p<0.05) in the atretic ears. Facial canal caliber, distance from the facial canal to the incudomalleolar joint and distance from the facial canal to the vestibule in the atretic ears (means: 1.49, 2.93 and 1.82, respectively) did not show statistically significant difference from the control subjects (means: 1.44, 2.91 and 1.83, respectively) (p>0.05 for all). CONCLUSION: External ear atresia is significantly associated with middle ear and mastoid abnormalities. The ossicles were underdeveloped which always have to be considered during reconstructive surgery. Radiologically, in the atretic ears anterior-posterior length of the temporal bone was more influenced as compared to superior-inferior portion, which justifies abnormal route of the facial nerve canal. However, there is no abnormality in the development of the facial nerve as the caliper is similar to the control subjects.     

Effects of a high jugular fossa and jugular bulb diverticulum on the inner ear. A clinical and radiologic investigation

From a series of patients undergoing routine radiographic examination, 112 temporal bones with a high jugular fossa were selected. Among these, 43 jugular bulb diverticula were found. The structures affected by a high fossa or diverticulum were recorded and correlated to the clinical symptoms of the patient. The vestibule was suspected to be affected in five patients. Two of these patients had tinnitus and vertigo, and three had hearing loss. In one of the latter the hearing loss was most marked in the supine position. The cochlea was close to the fossa in three patients, all of whom had tinnitus. Four patients had a defect of the posterior semicircular canal. One of them lost his hearing after a severe fit of coughing, became unsteady and showed signs of a fistula. The internal acoustic meatus and the mastoid portion of the facial canal were affected in two and four patients, respectively, who had no recorded symptoms. Twelve of 34 patients with Menière's disease and a high jugular fossa on the side of the diseased ear had a dehiscence of the vestibular aqueduct caused by the fossa or diverticulum, compared with nine of 58 patients in the unselected material. For comparison and demonstration of topographic relationships, 58 casts of unselected radiographed temporal bone specimens with high jugular fossae or diverticula were investigated. In patients with a high jugular fossa or jugular bulb diverticulum, tomographic assessment may be of value.     

Temporal bone trauma and the role of multidetector CT in the emergency department

The temporal bone anatomy is complex, with many critical structures in close association with one another. The temporal bone region comprises cranial nerves V, VI, VII, and VIII; vascular structures such as the internal carotid and middle meningeal arteries; sigmoid sinus; jugular bulb; and sensorineural and membranous structures of the inner ear. Most temporal bone fractures are a result of high-energy blunt head trauma. Multidetector computed tomography (CT) plays a fundamental role in the initial evaluation of patients with polytrauma in the emergency department. Multidetector CT may help identify important structural injuries that may have devastating complications such as sensorineural hearing loss, conductive hearing loss, dizziness and balance dysfunction, perilymphatic fistulas, cerebrospinal fluid leaks, facial nerve paralysis, and vascular injury. Although classifying temporal bone fractures helps physicians understand and predict trauma-associated complications and guide treatment, identifying injury to critical structures is more important for guiding management and determining prognosis than is simply classifying temporal bone fractures into a general category. Many temporal bone fractures and complications may be readily identified and characterized at routine cervical, maxillofacial, and head multidetector CT performed in patients with polytrauma, without the need for dedicated temporal bone multidetector CT. Dedicated temporal bone multidetector CT should be considered when there is a high degree of suspicion for temporal bone fractures and no fractures are identified at head, cervical, or maxillofacial CT.     

侵及颈静脉孔区的原发性中耳癌的CT、MRI诊断

目的 探讨侵及颈静脉孔区的原发性中耳癌的CT、MRI特点.方法 回顾性分析7例经手术病理证实的侵及颈静脉孔区原发性中耳癌患者的CT、MRI资料,其中6例行高分辨率CT(HRCT)扫描,1例行常规CT增强扫描,7例均行MR平扫+增强.结果 HRCT显示鼓室、鼓窦、外耳道深部及颈静脉孔区软组织病灶伴不规则虫蚀样骨质破坏,涉及颈静脉孔(7例)、咽鼓管骨性段(7例)、面神经管(4例)、颈动脉管(4例)、外耳道前后壁(3例)、听小骨(2例)及前庭窗、水平半规管(1例)等结构的破坏.4例病变密度较均匀,CT值约30～55 HU,2例肿块内见少许小片状高密度影.1例CT增强显示中度较均匀强化.MR平扫示边界不清软组织肿块,与脑灰质相比,T1WI呈等、略低信号,T2WI呈等、略高信号,其中5例信号较均匀,2例肿块内见少许小片状T1WI、T2WI低信号灶,增强扫描5例呈中度较均匀强化,2例不均匀强化,内见小片状无强化区.MRI显示4例侵及颈内动脉,1例侵及乙状窦.结论 原发性中耳癌可广泛侵及颈静脉孔区,易造成误诊.HRCT可准确显示中耳癌骨质破坏特点及范围,咽鼓管骨性段破坏可帮助减少误诊;MRI能更清楚显示病变范围,肿瘤信号及强化方式有一定特点.     

MR imaging of transverse/sigmoid dural sinus and jugular vein thrombosis

Magnetic resonance (MR) imaging was performed on six patients with thrombosis involving the transverse/sigmoid sinus and jugular bulb/vein. Venographic confirmation was obtained in five cases. Thrombi were characterized by increased intraluminal signal on all planes of section and pulse sequences. The change in signal intensity from first to second echo for thrombi was qualitatively less than that found with slow flow. Partial thrombosis in one case was seen as a ring pattern of central intermediate intensity corresponding to the thrombus, surrounded by a peripheral ring of signal void related to flowing blood. The MR findings closely correlated with venography in predicting thrombosis. Evidence of thrombi was not available from CT. Magnetic resonance is well suited for the diagnosis of occlusive disease of the dural venous sinus and jugular bulb.     

Imaging of pulsatile tinnitus: a review of 74 patients

OBJECTIVE: Our aim was to assess the effectiveness of imaging modalities in detecting the underlying pathologies in patients with pulsatile tinnitus. MATERIALS AND METHODS: Seventy-four patients with pulsatile tinnitus were radiologically evaluated. All patients except two are evaluated on a thin-section bone algorithm computed tomography scan covering the temporal bone and skull base, 14 patients with or without contrast-enhanced brain computed tomography, 7 patients with magnetic resonance imaging and magnetic resonance angiography, 5 patients with digital subtraction angiography, and 12 patients with Doppler ultrasonography. RESULTS: The underlying pathology of tinnitus was detected in 50 patients (67.6%), and 24 patients were normal with radiologic studies. The most common cause was high jugular bulbus (21%) followed by atherosclerosis, dehiscent jugular bulbus, aneurysm of internal carotid artery, dural arteriovenous fistula, aberrant internal carotid artery, jugular diverticulum, and glomus tumor. CONCLUSION: It was concluded that radiologic imaging methods are effective in detecting the underlying pathology of pulsatile tinnitus.     

An aberrant vascular channel in the petrous bone: persistent lateral capital vein?

An aberrant channel was identified on CT in the petrous bone in four patients presenting with unrelated otological symptoms. These channels occurred unilaterally in each case. In two patients, the channel was seen to run between the sigmoid sinus sulcus and the superior petrosal sinus sulcus; in one of these patients, a vascular structure was identified within this channel on MRI, connecting the sigmoid sinus and the superior petrosal sinus. In the two other patients, an aberrant channel was seen between the superior petrosal sinus sulcus and the posterior genu of the facial nerve canal. There were no symptoms that could be attributed to the presence of these channels. We postulate that these aberrant vascular channels correspond to a persistent embryological vein, the lateral capital vein.     

Association of internal carotid artery injury with carotid canal fractures in patients with head trauma

OBJECTIVE: The purpose of our study was to determine the degree to which carotid canal fracture and other CT findings are associated with internal carotid artery (ICA) injury in patients with head trauma. MATERIALS AND METHODS: Three neuroradiologists retrospectively evaluated CT scans and cerebral angiograms of 43 patients who underwent cerebral angiography within 7 days after blunt cranial trauma over a 5-year period. Seventeen patients underwent unilateral and 26 had bilateral carotid angiography. Angiograms were evaluated for ICA injury and CT scans were evaluated for carotid canal fracture, brain contusion, subarachnoid hemorrhage, basilar skull fracture, subdural hematoma, soft-tissue swelling, sphenoid sinus air-fluid level, and other skull fracture. We recorded the number of true-positive (+CT, +angiogram), true-negative (-CT, -angiogram), false-positive (+CT, -angiogram), and false-negative (-CT, +angiogram) studies. We determined the sensitivity, specificity, positive predictive value, and negative predictive value for each CT finding. RESULTS: We identified 21 carotid canal fractures in 17 patients. Eleven ICA injuries were seen in 10 patients. Six patients with ICA injury had a carotid canal fracture. The presence of a carotid canal fracture had a sensitivity of 60% and specificity of 67% for detection of injury to the ICA passing through that canal. These values were similar to those for other CT findings. CONCLUSION: Sensitivity, specificity, positive predictive value, and negative predictive value of carotid canal fracture were only moderately good for determining the presence of ICA injury and were similar to other CT findings not typically associated with ICA injury.     

Jugular bulb diverticula in medial petrous bone

Upward extension or diverticulum of the jugular bulb is rare. Most often, it protrudes into the middle ear. Three patients are reported in whom direct superior extension from the medial portion of the jugular bulb resulted in a defect in the medial part of the petrous bone. In this position, a jugular bulb diverticulum relates directly to the posterior wall of the internal auditory canal. The distinctive radiographic characteristics of this entity obviate unnecessary investigation and surgery. Encroachment on the internal auditory canal may possibly contribute to neurosensory hearing deficit.     

Parapharyngeal meningioma extending from the intracranial space

Summary A 50-year old woman with a giant parapharyngeal meningioma extending from the intracranial cavity was admitted to our hospital. The parapharyngeal tumor was biopsied using the transoral approach and a histological section diagnosis suggested meningioma. Thereafter, further examination by magnetic resonance images (MRI) and contrast enhanced CT scans revealed a diffuse meningioma en plaque in the posterior fossa. Invasion extended from the clival dura to the right sigmoid sinus. The extracranial extension of a meningioma is very rare but a few cases have been reported. In almost all of the reported cases, a large intracranial meningioma was simultaneously or previously verified by CT scans.Our case was special in that the intracranial mass was not voluminous but showed en plaque extension, and also because the pathway of the extracranial extension through the jugular foramen was clearly visualized by CT and MRI. Obliteration and invasion of the right sigmoid sinus and the internal jugular vein by tumor were also demonstrated.     

Development of posterior fossa dural sinuses,emissary veins,and jugular bulb: morphological and radiologic study.

PURPOSETo report the anatomic and radiologic development of the transverse, sigmoid, and occipital sinuses, the emissary veins, and the jugular bulb formation from the jugular sinus in humans before and after birth.METHODSRoentgenograms of 33 injected brains showing the cranial venous system in human fetuses from 3 to 7 months of gestational age and cerebral angiograms of newborns and infants up to 6 years of age (23 clinical cases) were made and analyzed in detail. Special attention was focused on the inner diameters of the transverse and sigmoid sinuses and of the internal jugular veins, particularly at the sigmoid sinus-internal jugular vein junction.RESULTSMarked increase in venous flow from the rapidly growing cerebral hemispheres leads to ballooning of the transverse sinuses in the absence of an increase in the inner diameters of the sigmoid and jugular sinuses. The ballooning also results in formation of the occipital sinus, marginal sinus around the foramen magnum, and emissary veins. The formation of the jugular bulbs from the jugular sinuses begins after birth when a shift from a fetal to a postnatal type of circulation (or from a lying-down position to an erect posture) takes place.CONCLUSIONThe morphological changes of the posterior fossa dural sinuses, emissary veins, and jugular bulb are closely related to the development of the brain, shift to postnatal type of circulation, and postural hemodynamic changes.     

Classification of temporal bone pneumatization based on sigmoid sinus using computed tomography

AIM: To analyse several reference structures using axial computed tomography (CT) imaging of the temporal bone, which may reflect pneumatization of the entire temporal bone by statistical correlation to the actual volume of the temporal bone measured using three-dimensional reconstruction. MATERIALS AND METHODS: One hundred and sixteen temporal bones were studied, comprising 48 with normal findings and 68 sides showing chronic otitis media or temporal bone fracture. After measuring the volume of temporal bone air cells by the volume rendering technique using three-dimensional reconstruction images, classification of temporal bone pneumatization was performed using various reference structures on axial images to determine whether significant differences in the volume of temporal bone air cells could be found between the groups. RESULTS: When the sigmoid sinus at the level of the malleoincudal complex was used in the classification, there were statistically significant differences between the groups that correlated with the entire volume of the temporal bone. Grouping based on the labyrinth and the ascending carotid artery showed insignificant differences in volume. Furthermore, there was no significant correlation between the cross-sectional area of the antrum and the entire volume of the temporal bone. CONCLUSION: The degree of pneumatization of temporal bone can be estimated easily by the evaluation of the air cells around the sigmoid sinus on axial CT images.     

CT检查在FESS术前计划制定中的价值

目的:探讨蝶窦与视神经、颈内动脉等邻近结构的CT影像解剖关系,为经蝶窦手术及诊断提供准确的影像解剖学依据。方法:CT扫描病例128例,年龄20～72岁,平均46.2岁;其中男79例,女49例。使用日本TOSHIBA公司生产的Aquilion 4螺旋CT。后台处理采用Vitrea 1处理系统。测量数据采用x±SD,百分数,t检验。结果:视神经管与蝶窦的关系:隆起型视神经管38例(29.69%),压迹型视神经管73例(57.03%),远离型视神经管17例(13.28%)。视神经走行与蝶窦外侧的关系:全程与蝶窦外侧壁毗邻者71侧(27.73%),全程与后组筛窦毗邻者66侧(25.78%),全程同时与蝶筛外侧壁毗邻者95侧(37.11%),全程穿过骨质者22侧(8.59%)。颈内动脉与蝶窦的关系:隆起型48侧(18.75%),压迹型101侧(39.45%),远离型107侧(41.80%)。结论:CT扫描结合MPR重组,能够清楚显示颈内动脉、视神经等与蝶筛外侧壁的解剖毗邻关系。CT检查有利于FESS手术进路的选择及手术方案的确定,为手术安全提供了保证。