鼻内镜鼻窦手术前筛窦颅底高度的CT评估价值

目的 探讨内镜鼻窦手术前应用CT评估筛窦颅底高度的价值。 方法 选取就诊于我院的100例共200侧的鼻窦冠状CT扫描图像,测量筛前动脉水平的筛顶中点至眶水平中线的距离,根据测量数据进行分型,同时进行Keros分型,用皮尔森相关系数来确定两者之间是否存在相关性。 结果 筛前动脉管水平的筛顶中点至眶水平中线的距离作为筛窦颅底高度。根据筛窦颅底的高度进行分型,其中Ⅰ型即筛窦颅底高度>7 mm(高位颅底)占44%(88/200),Ⅱ型即筛窦颅底高度介于4~7 mm(中位颅底)占41%(82/200),Ⅲ型即筛窦颅底高度<4 mm(低位颅底)占15%(30/200)。按Keros方法进行测量并分型,Ⅰ型占37%(74/200),Ⅱ型占52%(104/200),Ⅲ型占11%(22/200);Keros分型与筛窦颅底高度之间的皮尔森相关系数为0.384(P<0.001),Keros分型与筛窦颅底高度呈弱相关性。 结论 筛窦颅底高度存在明显差异,术前进行CT影像评估,可有效识别低颅底变异,有助于避免颅底损伤,进而减少内镜手术并发症。     

The surgeon's view of the anterior ethmoid artery

Objectives: To define the relationship of the anterior ethmoid artery to the frontal recess and secondly whether the degree of pneumatisation of the suprabullar recess/supraorbital cell correlates with the distance between the anterior ethmoid artery and the skull base thus making it more vulnerable to damage during surgery. Method: Thirty‐four cadaver head sides were perfused with pink latex. All specimens had high‐resolution computed tomography (CT) scans using bone windows in the axial, coronal and sagittal planes. The specimen's nasal septum was removed and the ethmoid sinuses dissected to locate the anterior ethmoid artery. Calipers were used to measure distance between the artery and the frontal recess and from the skull base. Results: The anterior ethmoid artery was found in all the specimens and scans. The distance between the anterior ethmoid artery and the posterior wall of the frontal recess was 11 mm (range 6–15 mm). In all specimens, the artery was seen between the second and third lamella. The commonest location of the artery was in the suprabullar recess (85.3%). Supraorbital cells were seen in 16 specimens. The ethmoid sinuses were well pneumatised with a large supraorbital cell in 10 of these specimens and in these the artery was lying 3.7 mm (range 1–8 mm) away from the skull base. Six specimens had poor pneumatisation and a small supraorbital cell and in these the artery was found close to or with in the skull base. In specimens without a supraorbital cell, the artery lay at the skull base in all but one. Conclusions: The position of the anterior ethmoidal artery is very variable. The artery is found between the second and third lamella. When the ethmoid sinuses are more pneumatised and in particular when there is a supraorbital cell, the artery lies below the skull base. A good strategy is to identify the degree of pneumatisation of the ethmoid sinuses from CT scans preoperatively to see if the artery is at an increased risk of being damaged.     

Sagittal and coronal dimensions of the ethmoid roof: a radioanatomic study

BACKGROUND: Understanding the anatomy of the ethmoid roof is critical to safe surgical outcomes. Normative data regarding the height and slope of this region have been somewhat limited, derived primarily from cadaveric coronal computed tomography (CT) studies. With triplanar imaging programs, precise multidimensional measurements of the ethmoid roof are now possible. We present a radioanatomic study to characterize normative sagittal and coronal dimensions of the ethmoid roof. METHODS: Bilateral measurements were taken in 100 consecutive sinus CT scans using ThinClient 3D software. In the sagittal plane, the height of the ethmoid roof was measured in quadrants at five equidistant points between the frontal beak and sphenoid face, referencing the nasal floor. In the coronal plane, the ethmoid roof was measured at three points at the level of the anterior ethmoid artery and at two points at the junction of the posterior ethmoid and sphenoid sinuses. RESULTS: When examined sagittally, the right side showed significantly lower skull base heights in the anterior ethmoid compared with the left side (59.0 mm versus 59.8 mm, p = 0.017; 53.7 mm versus 54.5 mm, p = 0.0004). Coronal measurements of the anterior ethmoid roof showed similar significant differences. The anterior ethmoid roof had greater asymmetries of height compared with the posterior ethmoid roof, which was fairly constant. CONCLUSION: This study provides numerical correlates to accepted concepts regarding the shape and slope of the ethmoid roof. Differences in height of the skull base between right and left sides, especially in the anterior ethmoid sinus, may be an important surgical consideration. The posterior ethmoid roof appears to be relatively constant and should serve as a reliable surgical landmark.     

筛窦顶壁影像学分析

目的:探讨筛窦顶壁高度及形态影像解剖学特征。方法:回顾性分析160例冠状位鼻窦CT,观察左 右侧筛窦顶壁形态及高度对称性、筛窦顶壁与筛板连接方式,测量左右侧筛窦顶壁高度差及筛窦顶壁与筛板间高 度差。结果:左右侧筛窦顶高度(差>1mm)不对称者25例(15.63%),其中右侧筛窦顶较左侧低13例 (52.00%),左右侧筛窦顶高度差平均为2.35mm。左右侧筛窦顶形态62例(38.75%)不对称,一侧鸟翼状另一 侧扁平状。筛窦顶与筛板水平式连接116侧(36.25%),高台式连接204侧(63.75%)。高台型筛窦顶与筛板高 度差平均为2.80mm。结论:筛顶在高度及形态上存在左右侧不对称性,且以形态的不对称性为常见。筛窦顶壁 与筛板的连接方式以高台式多见。鼻内镜手术前及手术中仔细阅读患者鼻窦CT片具有重要意义。     

Configuration of ethmoid roof in children 0-14 years of age

BACKGROUND: Knowledge of the unique anatomy of the nose, paranasal sinuses and skull base, particular concerning dangerously low positioned or deep lying cribriform plates is most important, as functional endoscopic sinus surgery has become an increasingly popular procedure for the management of pediatric sinus disease. OBJECTIVES AND METHODS: In addition to Keros who studied the ethmoidal roof and cribriform plate in 450 adult specimen and divided them into 3 groups, retrospective analysis in 272 patients between 0 and 14 years was performed by means of coronal CT scans of the paranasal sinuses with a slice thickness of 2 mm. Measurements were carried out in the frontal, middle and dorsal section of the ethmoid. RESULTS: The depth and width of the fossa olfactoria were significantly less in patients aged 0 - 12 months than in other age groups (p < 0.001). Among the other age groups, beginning at 2 years no differences were found: 14.2 % presented with type I according to Keros, 70.6 % with Keros II and 15.2 % with Keros III. The prevalence of asymmetric position of the ethmoidal roof was 15 % (41 patients). The height of the ethmoidal sinuses consistently increased over the years from 5 - 7 mm to 15 - 20 mm. CONCLUSION: The current data may serve as a reference for evaluation of normal and abnormal development of the roof of the ethmoid and may be of great value in diagnostic and therapeutic management of pediatric sinus disease. Our data obviously show that the classification into the 3 types of positions of the ethmoid roof and cribriform plate according to Keros is possible in children from the second year of life.     

New guidelines for endoscopic localization of the anterior ethmoidal artery: a cadaveric study

OBJECTIVES: To determine objective data to improve the methods of identification of the anterior ethmoidal artery during endoscopic dissection. STUDY DESIGN: Cadaveric dissection of adult human heads. METHODS: A 0 degrees, 4-mm rigid endoscope was used to guide uncinectomy and frontoethmoidectomy. The location of the anterior ethmoidal artery was first determined visually and then confirmed by passing a needle through the anterior ethmoidal foramen from the orbit into the nose in all cases. The distances were endoscopically measured using a simple ruler between two nasal landmarks and the anterior ethmoidal artery. RESULTS: Fifty-six nasal fossae in 28 cadavers were dissected endoscopically. The median distance between the artery and the "axilla" formed by the anterior attachment of the middle turbinate to the lateral nasal wall was 20 mm (range, 17-25 mm), irrespective of the side. The measurement differed by less than 2 mm between the sides in the same individual. The median distance between the artery and the "axilla" formed by the medial and lateral crura of the lower lateral cartilage (superomedial edge of the nostril) was 62 mm (range, 55-75 mm) for both sides. The artery was found to be in direct alignment with the two "axillae" formed by the middle turbinate and the nostril edge. CONCLUSIONS: The distance between the ethmoidal artery and the axilla of the middle turbinate showed the least intraindividual and interindividual variations. The tip of the endoscope (or the ruler) points directly at the anterior ethmoidal artery in the fovea ethmoidalis when its edge is aligned with the two nasal landmarks. These simple guidelines can aid the identification of the artery in endoscopic frontoethmoidectomy.     

鼻内镜下切除筛窦骨瘤13例

目的:报告鼻内镜下切除筛窦骨瘤13例(14侧),并探讨相关的技术方法.方法:采用回顾性研究方法,并复习文献进行讨论.13例筛窦骨瘤患者,7例(8侧)术前CT示骨瘤未附着在纸样板、前颅底,在鼻内镜下解剖骨瘤与周围的联系后切除;4例术前CT示骨瘤附着在纸样板、2例术前CT示骨瘤附着在前颅底,在鼻内镜下解剖、暴露骨瘤后用电钻磨除.结果:13例(14侧)筛窦骨瘤在鼻内镜下完整切除,无眶内和颅内并发症,所有患者术腔在6～8周内上皮化.结论:术前冠位加轴位CT扫描能较完整评价骨瘤与筛窦各壁的关系,为手术方法和器械的选择提供有益的帮助;鼻内镜下配合适宜的手术器械,如电钻等切除筛窦骨瘤,无面部瘢痕、创伤小,是经鼻内途径切除筛窦骨瘤的理想选择.     

Endoscopic anterior ethmoidal artery ligation: a cadaver study

OBJECTIVE: The objective of this study was to investigate the radiologic and endoscopic anatomy of the anterior ethmoidal canal (AEC) and feasibility of endoscopic ligation of the anterior ethmoidal artery (AEA). STUDY DESIGN: The authors conducted a prospective analysis of computed tomography (CT) of the paranasal sinuses and endoscopic cadaver dissection. METHODS: Twenty-two cadaver heads had CT scans of the paranasal sinuses. The height of the lateral lamella of the cribriform plate was calculated and staged according to the Keros staging system. The presence of a bony mesentery, distance from AEC to the skull base, and dehiscence of the AEC were documented. Forty-four dissections were performed, the AECs identified, and AEA ligation attempted. RESULTS: The mean height of the lateral lamella was 5.4 mm on the right and 4.7 mm on the left. In all cadaver heads with asymmetry, the right lateral lamella was longer (P<.005). A Keros type 1 pattern was seen in 23%, type 2 in 50%, and type 3 in 27%. Thirty-six percent of AECs were in a bony mesentery. AEC distance from the skull base was greater on the right (P<.009). A longer lateral lamella was correlated with the artery being in a mesentery. Sixteen percent of the AECs were dehiscent. Sixty-six percent of AEAs were unable to be clipped. Twenty percent were clipped effectively, all in a mesentery. In 14%, the AEA was not effectively clipped. CONCLUSIONS: Endoscopic AEA ligation may be possible in some patients. The AEA should be in a mesentery for an effective clip to be placed and be associated with a dehiscence of the AEC. If the lateral lamella is classified as Keros grade 2 or 3, it is likely the AEC will be found in a mesentery.     

鼻内镜手术中扩大上颌窦自然口的意义

目的：探讨鼻内镜手术中扩大上颌窦自然口对上颌窦炎转归的影响。方法：将慢性上颌窦炎218例随机均分为两组，A组的手术范围是切除钩突、筛泡，开放前、中、后组筛窦，扩大上颌窦自然开口，切除部分肥厚明显的中鼻甲；B组手术范围是切除钩突、筛泡，开放前、中组筛窦，不处理上颌窦自然开口，尽量保留中鼻甲,特别肥厚者也行部分切除。结果：218例均随访1年以上。按海口1997年疗效评定标准，A组治愈100例,治愈率92%，B组治愈99例,治愈率91%；A组好转9例,好转率8%，B组好转10例,好转率9%。结论：鼻内镜手术范围的关键是切除窦口鼻道复合体的解剖变异，是否扩大上颌窦口并不十分重要。     

Preoperative CT scanning for endoscopic sinus surgery: a rational approach.

Recent research on inflammatory sinus disease has implicated a central role for the ethmoid labyrinth, which may influence changes in the maxillary and frontal sinuses. CT can provide excellent definition of the paranasal sinuses and particularly the ethmoids, which is a prerequisite for endoscopic surgery. We describe a prospective series of 110 coronal CT scans performed on patients with a clinical diagnosis of sinusitis who had undergone diagnostic nasal endoscopies and medical treatment prior to surgery. 86% of the scans showed abnormal mucosal thickening. The ethmoids were affected in 73% and the maxillary sinus in 64%. Pneumatization of the middle turbinate was a common variant and when present was associated with anterior ethmoid disease in 60% of patients. Anterior ethmoid inflammatory changes were demonstrable in 95% of patients with maxillary sinus disease. Direct coronal CT can readily demonstrate disease in the infundibulum, frontal recess and posterior ethmoids in the same orientation confronting the endoscopist, and helps in the planning of ethmoidal surgery. Following surgery the sinuses can be directly inspected in outpatients which reduces the need for any further plain radiographs. It is important that the diagnosis of sinusitis is not based on CT findings alone as isolated areas of mucosal thickening are common in the normal population.     

Frontobasal fractures in children

In 1987, four children between 5 and 13 years of age with severe frontobasal trauma and dural tears were treated operatively. A CSF rhinorrhea was manifest clinically in only two cases. In addition high-resolution computerised tomography was essential in diagnosis and planning of the operation. In each of the cases an intracranial pneumatocele indicating dural laceration was shown. The fractures were confirmed during surgery in: Case 1. The roof of the ethmoid sinus and the roof of the orbit. Case 2. Both the sphenoid sinuses. Case 3. The roof of the ethmoid sinus and the posterior wall of the frontal sinus. Case 4. The roof of the ethmoidal sinus and the posterior wall of the frontal sinus. The ontogenetically oldest part of the paranasal sinuses in the floor of the anterior cranial fossa forming the anterior part of the roof of the ethmoid bone is the site of predilection for fractures, even in children. The anterior cranial fossa was exposed in each case through a paranasal subfrontal access, in the first case combined with a frontal craniotomy by a neurosurgeon, because of the fracture of the roof of the orbit. In the second case the dural injury had to be closed at a second neurosurgical operation, because of a recurrence of the CSF leak. The third and fourth cases were treated by nasal surgery alone.     

Preoperative CT scanning for endoscopic sinus surgery: a rational approach

Recent research on inflammatory sinus disease has implicated a central role for the ethmoid labyrinth, which may influence changes in the maxillary and frontal sinuses. CT can provide excellent definition of the paranasal sinuses and particularly the ethmoids, which is a prerequisite for endoscopic surgery. We describe a prospective series of 110 coronal CT scans performed on patients with a clinical diagnosis of sinusitis who had undergone diagnostic nasal endoscopies and medical treatment prior to surgery. 86% of the scans showed abnormal mucosal thickening. The ethmoids were affected in 73% and the maxillary sinus in 64%. Pneumatization of the middle turbinate was a common variant and when present was associated with anterior ethmoid disease in 60% of patients. Anterior ethmoid inflammatory changes were demonstrable in 95% of patients with maxillary sinus disease. Direct coronal CT can readily demonstrate disease in the infundibulum, frontal recess and posterior ethmoids in the same orientation confronting the endoscopist, and helps in the planning of ethmoidal surgery. Following surgery the sinuses can be directly inspected in outpatients which reduces the need for any further plain radiographs. It is important that the diagnosis of sinusitis is not based on CT findings alone as isolated areas of mucosal thickening are common in the normal population.     

Anatomic variations of the paranasal sinuses: CT examination for endoscopic sinus surgery

Chronic rhinosinusitis endoscopic surgery requires an accurate evaluation of diseases and paranasal sinus anatomic variations. This study aims to show the main anatomical variations in the ostiomeatal complex and paranasal sinuses which are usually depicted by computed tomography (CT). CT scans obtained 2 mm thickness in axial and coronal plane from a series of 200 patients with chronic sinusitis were examined to determine the prevalence of anatomic variants. Anatomical variations determined were supraorbital recess in 6%, concha bullosa in 30%, sphenomaxillary plate in 17%, infra-orbital ethmoid cells (Haller's cells) in 6%, spheno-ethmoid cells (Onodi's cells) in 12%, pneumatization of the anterior clinoid process in 6%, carotid artery bulging into the sphenoid sinus in 8%, pneumatization of the uncinate process in 2%, paradoxical curvature of the middle turbinate in 3% and septal deviation in 36%. Level difference between the ethmoid roof and nasal vault was an average of 8 mm in right side and 9.5 mm in left side. Awareness of these different variations will help the rhinologic surgeon in his orientation during endoscopic surgical procedures.     

眶上筛房在CT和鼻内镜下的临床特征

目的通过分析眶上筛房在CT和鼻内镜下的临床特征，进一步阐明眶上筛房和额窦引流通道的关系。方法通过术前评估冠状位和水平位CT和术中鼻内镜所见，确诊眶上筛房5侧（男4例，女1例，每例1侧）。结果①眶上筛房在冠状位CT上表现为额窦区域最外侧的气房；②眶上筛房在水平位CT上表现为额窦后外方的气房；③鼻内镜下见额窦和眶上筛房均引流至前筛顶部，眶上筛房的引流通道位于额窦引流口的后外方，眶上筛房向外上方气化，从后方进入额窦。结论CT和鼻内镜观察证实眶上筛房是位于筛泡上方的气房向上、向外延展过程中，超过了筛骨眶板和筛顶的范围，导致额骨眶板气化而成。     

Computed tomography anatomy of the anterior ethmoid canal

The roof of the anterior ethmoid swings up anteriorly from its more or less horizontal course at the point where the anterior ethmoid canal (AEC) is situated. The AEC is an important structure in endoscopic sinus surgery since its injury results in bleeding into the nasal cavity and may result in intraorbital bleeding. We therefore investigated the location of this canal and the anatomic characteristics of the area surrounding the canal using coronal computed tomography (CT) of the paranasal sinuses. One hundred sides of 50 paranasal coronal CT images in patients with sinusitis were analyzed to assess the location of the AEC, the shape of the superolateral wall of the ethmoid sinus anterior and posterior to the AEC, and pneumatization of the roof of the anterior ethmoid sinus. The AEC is situated in the second quarter of the roof of the ethmoid sinus. The superolateral wall anterior to the AEC demonstrated an acute angle in 99% of sides, while the superolateral wall posterior to the AEC showed an obtuse angle in 87% of sides. The ethmoid cell anterior to the AEC pneumatized posteriorly over the AEC in 26% of sides. We conclude that coronal CT confirmation of the anatomic characteristics of the AEC, and the area surrounding the canal, is invaluable for preoperative planning for endoscopic sinus surgery.     

鼻内窥镜下鼻腔泪囊吻合术的有关前组筛窦应用解剖

目的：为鼻内窥下鼻腔泪囊吻合术提供解剖学指导。方法：对１６具（３２侧）成人尸头的前组筛窦解剖进行研究,同时观察了钩突与眶内仙壁的毗邻结构关系。结果：根据前组筛窦与泪囊窝的解剖关系将前组筛窦分为三种类型：Ⅰ型为前组筛房前界达泪囊窝的后泪嵴;Ⅱ型为前组筛房前界达泪窝的泪颌缝;Ⅲ型为前组筛前界超过泪凳缝达前泪嵴。其中Ⅰ型占３１．２％,Ⅱ型占５０．％,Ⅲ型占１８．８％,结论：对不同类型的鼻泪管阻塞的患者,     

慢性鼻窦炎鼻息肉再次内镜鼻窦手术

目的 探讨需行再次内镜鼻窦手术的原因，评价再次内镜鼻窦手术的疗效。方法 对114例（161侧）需行再次内镜鼻窦手术的患者术前行鼻内镜和鼻窦CT扫描检查，术后随访2例以上。结果 114例（161侧）中复发性鼻窦炎98例（129侧），复发性鼻息肉16例（32侧）。额隐窝狭窄2例（3例），前组筛窦炎18例（24侧），前组筛窦炎和上颌窦自然开口堵塞31例（46侧），中鼻甲粘连6例（7侧），后组筛窦炎18例（24侧），后组筛窦和蝶窦炎36例（54侧），蝶窦炎3例（3侧）。伴有鼻中隔偏曲者15例。经2年以上随访，复发性鼻窦炎者88例（111侧）痊愈，10例（18侧）症状缓解，16例（32侧）复发性鼻息肉患者11例（22例）痊愈，5例（10例）症状缓解。结论 行再次内镜鼻窦手术的原因主要是前次手术未彻底清除病变（首先与术者经验不足有关）；其次为鼻息肉病。再次内镜鼻窦手术效果满意，无严重并发症。     

Asymmetry of the ethmoid roof: analysis using coronal computed tomography.

OBJECTIVES/HYPOTHESIS: To determine the incidence and degree of asymmetry in the height and contour of the ethmoid roof. STUDY DESIGN: Retrospective review of direct coronal paranasal sinus computed tomography (CT) scans. METHODS: Retrospective review of 200 consecutive direct coronal sinus CT scans done at New York University Medical Center from July 25, 2000 to October 11, 2000. The height and contour of the fovea ethmoidalis were examined for symmetry between the right and left sides. When an asymmetry in the height of the fovea ethmoidalis existed, this difference was quantified. RESULTS: In 19 scans (9.5%), there was an asymmetry between the height of the fovea ethmoidalis on the right and left sides. Of these 19, 12 (63.2%) were lower on the right side, whereas 7 (36.8%) were lower on the left. Ninety-six patients (48.0%) demonstrated a contour asymmetry with "flattening" of the ethmoid roof on one side, 46 on the right and 50 on the left. One patient demonstrated both height and contour asymmetry. The fovea ethmoidalis on the remaining 86 scans (43.0%) was symmetric. CONCLUSIONS: In a patient population with sinus and nasal symptoms, the height and contour of the right and left fovea ethmoidalis were symmetric in less than 50% of individuals. The asymmetry was most often the result of a difference in contour with flattening of the fovea on one side. This underscores the importance of careful preoperative and intraoperative review of paranasal sinus CT scans in patients undergoing endoscopic sinus surgery.     

Anterior skull base: High risk areas in endoscopic sinus surgery in chronic rhinosinusitis: A computed tomographic analysis

Computed Tomography (CT) scan of nose and paranasal sinuses play a key role in preoperative evaluation of patients undergoing endoscopic sinus surgeries (ESS) for chronic rhinosinusitis. The asymmetry of ethmoid fovea olfactory fossa, anatomical variations of lateral lamella and course of anterior ethmoid artery are critical in ESS as it may predispose to dangerous consequences like hemorrhage. CSF leak and intracranial complications. A prospective study was done on 75 patients of clinically and diagnostically proven chronic rhinosimusits. The coronal CT scan was evaluated with special attention to anatomical variations of anterior skull base including ethmoid fovea, olfactory fossa, lateral lamella and course of anterior ethmoid artery. The endoscopic surgeon's awareness of these variations and its role in preventing complications are highlighted.