CT仿真内镜与多平面重建对垂体瘤患者蝶窦显示情况的比较

目的:比较CT仿真内镜(CT virtual endoscopy,简称CTVE)与CT多平面重建(multiplannar reconstruction,MPR)对垂体瘤患者蝶窦、鞍底的显示情况.方法:在119例垂体瘤经蝶手术中,对术前常规垂体CT检查数据分别进行MPR及CTVE重建,对两者显示的蝶窦情况进行比较.结果:在蝶窦表面解剖结构:蝶窦开口、蝶窦中隔、鞍底形状、斜坡凹陷、颈内动脉隆起、视神经管隆起方面,CTVE与MPR的显示率无明显差别,CTVE对颈内动脉视神经隐窝的显示率优于MPR,CTVE所提供的为三维图像,MPR提供的为二维图像.在显示深部解剖标志:斜坡松质骨、蝶窦壁厚度方面MPR明显优于CTVE.结论:CTVE能显示蝶窦浅表解剖结构的三维图像,可做为经蝶垂体瘤手术的术前了解蝶窦三维解剖结构的一种方法.     

内镜下经鼻蝶入路视神经管减压术应用解剖

目的　为内镜下行经鼻蝶入路视神经管减压术提供解剖学依据。 方法 选用12例成人尸颅标本,模拟内镜下经鼻蝶入路,观察视神经管及其周围结构。磨除视神经管,暴露并打开管内视神经鞘膜,观察鞘膜内视神经及眼动脉。 结果 视神经隆突是蝶窦内相对恒定的解剖标志,通过它可以确定视神经管眶口;眼动脉多走行于视神经的腹内侧,切开视神经鞘膜时应在外上壁进行。 结论 视神经隆突是重要的解剖标志;应在外上壁切开视神经鞘膜。     

A comparison of hepatic segmental anatomy as revealed by cross‐sections and MPR CT imaging

To compare the areas of human liver horizontal sections with computed tomography (CT) images and to evaluate whether the subsegments determined by CT are consistent with the actual anatomy. Six human cadaver livers were made into horizontal slices with multislice spiral CT three‐dimensional (3D) reconstruction was used during infusion process. Each liver segment was displayed using different color, and 3D images of the portal and hepatic vein were reconstructed. Each segmental area was measured on CT‐reconstructed images, which were compared with the actual area on the sections of the same liver. The measurements were performed at four key levels namely: (1) the three hepatic veins, (2) the left, and (3) the right branch of portal vein (PV), and (4) caudal to the bifurcation of the PV. By dividing the sum of these areas by the total area of the liver, the authors got the percentage of the incorrectly determined subsegmental areas. In addition to these percentage values, the maximum distances of the radiologically determined intersegmental boundaries from the true anatomic boundaries were measured. On the four key levels, an average of 28.64 ± 10.26% of the hepatic area of CT images was attributed to an incorrect segment. The mean‐maximum error between artificial segments on images and actual anatomical segments was 3.81 ± 1.37 cm. The correlation between radiological segmenting method and actual anatomy was poor. The hepatic segments being divided strictly according to the branching point of the PV could be more informative during liver segmental resection. Clin. Anat. 2013. © 2012 Wiley Periodicals, Inc.     

A Morphometric Study of the Semicircular Canals Using Micro‐CT Images in Three‐Dimensional Reconstruction

It is generally accepted that the three semicircular canals are set at right angles to each other and the lateral semicircular canal is smaller than the anterior and posterior semicircular canals. Precise knowledge of the size and spatial relationships of the semicircular canals is vital, and so the 40 petrous parts of the temporal bones were scanned by micro‐CT at a slice thickness of 35 µm. The micro‐CT images were used in reconstructing three‐dimensional models of the bony labyrinth using computer software. Various dimensions of the semicircular canals were measured using the software, and statistical analysis was performed. The anterior semicircular canal was slightly wider than the posterior semicircular canal, and their heights were similar. The radius of curvature of the lateral semicircular canal was 20% smaller than those of the anterior and posterior semicircular canals. The angles between the three canals were not exactly 90 degrees: they were 92.1, 84.4, and 86.2 degrees between the anterior and posterior, anterior and lateral, and posterior and lateral semicircular canals, respectively. We obtained high‐resolution images of the semicircular canals using three‐dimensional reconstruction software, and these were used to precisely measure the angles between the semicircular canals and the area of the distorted circle formed by each semicircular canal. Anat Rec, 296:834–839, 2013. © 2013 Wiley Periodicals, Inc.     

内镜经鼻入路视神经管和眼眶的解剖学

目的通过研究对视神经管和眼眶的解剖研究,为内镜经鼻入路视神经管减压和治疗眼眶内病变提供解剖基础。方法国人尸头5例,采用大体解剖和内镜下经鼻入路两种方法,观察重要的解剖标志;使用内直肌内移技术,观察视神经管和眼眶内结构的暴露情况以及重要结构的位置、毗邻、走行等。结果钩突位于中鼻甲的前下方;筛泡在钩突的后方,切开筛泡可进入筛窦;筛前后动脉是筛窦内的重要解剖标志;视神经管隆突、颈内动脉隆突和视神经管颈内动脉隆突(OCR)是蝶窦内重要的解剖标志;纸样板位于筛窦的外侧壁,切开纸样板可暴露眶内容物;在眶内,可从内直肌与下直肌之间的通路暴露视神经。在本次10侧标本中,9侧眼动脉起自于颈内动脉的床突上段;1侧眼动脉起自于颈内动脉海绵窦段。7侧眼动脉在视神经管内走行于视神经的下外侧;2侧走行于视神经的正下方;1侧走行于视神经的下内侧。结论内镜下经鼻入路可以进行视神经管和眼眶内侧部分的暴露。钩突、筛泡、筛前后动脉及后组筛窦是本入路重要解剖标志。视神经管隆突、颈内动脉隆突及视神经管颈内动脉隆突(OCR)是进行视神经管减压的重要标志。眼动脉及其眼眶内分支、筛前后动脉和颈内动脉是重要的血管结构。眼内直肌内移技术可以有助于暴露眶内解剖结构。     

The Relationships of the Maxillary Sinus With the Superior Alveolar Nerves and Vessels as Demonstrated by Cone‐Beam CT Combined With μ‐CT and Histological Analyses

There are no available detailed data on the three‐dimensional courses of the human superior alveolar nerves and vessels. This study aimed to clarify the relationships of the maxillary sinus with the superior alveolar nerves and vessels using cone‐beam computed tomography (CT) combined with μ‐CT and histological analyses. Digital imaging and communication in medicine data obtained from the scanned heads/maxillae of cadavers used for undergraduate/postgraduate dissection practice and skulls using cone‐beam CT were reconstructed into three‐dimensional (3D) images using software. The 3D images were compared with μ‐CT images and histological sections. Cone‐beam CT clarified the relationships of the maxillary sinus with the superior alveolar canals/grooves. The main anterior superior alveolar canal/groove ran anteriorly through the upper part of the sinus and terminated at the bottom of the nasal cavity near the piriform aperture. The main middle alveolar canal ran downward from the upper part of the sinus to ultimately join the anterior one. The main posterior alveolar canal ran through the lateral lower part of the sinus and communicated with the anterior one. Histological analyses demonstrated the existence of nerves and vessels in these canals/grooves, and the quantities of these structures varied across each canal/groove. Furthermore, the superior dental nerve plexus exhibited a network that was located horizontally to the occlusal plane, although these nerve plexuses appeared to be the vertical network that is described in most textbooks. In conclusion, cone‐beam CT is suggested to be a useful method for clarifying the superior alveolar canals/grooves including the nerves and vessels. Anat Rec, 299:669–678, 2016. © 2016 Wiley Periodicals, Inc.     

Whole‐Mount Imaging Demonstrates Hypervascularity of the Pancreatic Ducts and Other Pancreatic Structures

Confocal microscopy in combination with commercial software is frequently used to generate three‐dimensional images of tissue architecture. Here we report a novel, whole‐mount imaging protocol technique that allows detailed three‐dimensional imaging of adult pancreatic structures. This technique provides an improved appreciation of the anatomical detail of pancreatic structures and of the relationship between the pancreatic ducts and islets. In addition, imaging of the pancreatic ducts revealed a previously unappreciated high degree of hypervascularity. Anat Rec, 2012. © 2012 Wiley Periodicals, Inc.     

15例成年国人颞骨内部结构CT解剖学

目的:研究成年国人颞骨内部解剖结构的CT重建图像,为临床耳显微外科及神经外科手术提供解剖学依据。方法:15名健康志愿者应用Picker5000螺旋CT机,平行于听眦线扫描,应用VoxelQ工作站进行多层面重建(multi planar reconstruction,MPR),表面遮盖重建(surface shaded display,SSD)及仿真内窥镜成像(CT virtual endoscopy,CTVE),多角度旋转观察颞骨内部解剖结构。结果:MPR能在不同切面显示耳蜗、半规管、内耳道及面神经管垂直段等结构,显示率为100%;SSD能清晰显示颞骨重要的骨性结构,如内耳门、颈静脉孔等,冠状位切割后的SSD图像能生动地显示锤骨、砧骨的立体形态及空间关系;CTVE可模仿内窥镜从外耳向中耳移动,清晰显示骨性外耳道、鼓室内侧壁及听骨链等结构。结论:MPR可行多方位重建,有助于耳颞部病变的全面了解,是轴位CT良好的补充;SSD、CTVE可准确、立体的观察颞骨内部解剖结构,对临床诊断、手术方案的设计、医学教学等具有指导意义。     

Feldkamp-based cone-beam reconstruction for gantry-tilted helical multislice CT

Depending on the clinical application, it is frequently necessary to tilt the gantry of an x-ray CT system with respect to the patient and couch. For single-slice fan-beam systems, tilting the gantry introduces no errors or artifacts. Most current systems, however, are helical multislice systems with up to 16 slices. The multislice helical reconstruction algorithms used to create CT images must be modified to account for tilting of the gantry. If they are not, the quality of reconstructed images will be poor with the presence of significant artifacts, such as smearing and double-imaging of anatomical structures. Current CT systems employ three primary types of reconstruction algorithms: helical fan-beam approximation, advanced single-slice rebinning, and Feldkamp-based algorithms. This paper presents a generalized helical cone-beam Feldkamp-based algorithm that is valid for both tilted and nontilted orientations of the gantry. Unlike some of the other algorithms, generalization of the Feldkamp algorithm to include gantry tilt is simple and straightforward with no significant increase in computational complexity. The effect of gantry tilt for helical Feldkamp reconstruction is to introduce a lateral shift in the isocenter of the reconstructed slice of interest, which is a function of the tilt, couch speed, and view angle. The lateral shift is easily calculated and incorporated into the helical Feldkamp backprojection algorithm. A tilt-generalized helical Feldkamp algorithm has been developed and incorporated into Aquilion 16-slice CT (Toshiba, Japan) scanners. This paper describes modifications necessary for the tilt generalization and its verification.     

Postnatal Mandibular Cheek Tooth Development in the Miniature Pig Based on Two‐Dimensional and Three‐Dimensional X‐Ray Analyses

The miniature pig is a useful large laboratory animal model. Various tissues and organs of miniature pigs are similar to those of humans in terms of developmental, anatomical, immunological, and physiological characteristics. The oral and maxillofacial region of miniature pigs is often used in preclinical studies of regenerative dentistry. However, there is limited information on the dentition and tooth structure of miniature pigs. The purpose of this study was to examine the time‐course changes of dentition and tooth structure (especially the root) of the miniature pig mandibular cheek teeth through X‐ray analyses using soft X‐ray for two‐dimensional observations and micro‐CT for three‐dimensional observations. The mandibles of male Clawn strain miniature pigs (2 weeks and 3, 5, 7, 9, 11, 14, 17, and 29 months of age) were used. X‐ray analysis of the dentition of miniature pig cheek teeth showed that the eruption pattern of the miniature pig is diphyodont and that the replacement pattern is vertical. Previous definitions of deciduous and permanent teeth often varied and there has been no consensus on the number of teeth (dentition); however, we found that three molars are present in the deciduous dentition and that four premolars and three molars are present in the permanent dentition. Furthermore, we confirmed the number of tooth roots and root canals. We believe that these findings will be highly useful in future studies using miniature pig teeth. Anat Rec, 2013. © 2013 Wiley Periodicals, Inc.     

Three‐Dimensional Study of the Facial Canal Using Microcomputed Tomography for Improved Anatomical Comprehension

The aims of this study were to determine the various dimensions of the normal facial canal and to identify the spatial relationships between the facial canal and its adjacent structures using microcomputed tomography (micro‐CT) imaging and three‐dimensional (3D) reconstruction. The petrous parts of 54 temporal bones were scanned using micro‐CT with a slice thickness of 35 μm. The serial micro‐CT images were used to reconstruct 3D volumes of the facial canal and the bony labyrinth with the aid of computer software. These volumes were used to measure 31 dimensions of the facial canal and its spatial relationships with adjacent structures. The length of the meatal segment, the tympanic segment, and the mastoid segment were significantly larger in males than in females (p < 0.05). The narrowest portions of the facial canal were immediately lateral to the meatal foramen in the labyrinthine segment and the midpoint of the tympanic segment. The distance between the origin of the canal for the chorda tympani nerve and midpoint of the stylomastoid foramen was 35.3% of the length of the mastoid segment, and the angle between the tympanic segment and the lateral semicircular canal was 16.3°. The angle between the mastoid segment and the canal for the chorda tympani nerve could be classified into two groups: <180° and >180°. These findings represent supplemental data for improving the detailed understanding of the facial canal anatomy. Anat Rec, 297:1808–1816, 2014. © 2014 Wiley Periodicals, Inc.     

A knowledge-based cone-beam x-ray CT algorithm for dynamic volumetric cardiac imaging

With the introduction of spiral/helical multislice CT, medical x-ray CT began a transition into cone-beam geometry. The higher speed, thinner slice, and wider coverage with multislice/cone-beam CT indicate a great potential for dynamic volumetric imaging, with cardiac CT studies being the primary example. Existing ECG-gated cardiac CT algorithms have achieved encouraging results, but they do not utilize any time-varying anatomical information of the heart, and need major improvements to meet critical clinical needs. In this paper, we develop a knowledge-based spiral/helical multislice/cone-beam CT approach for dynamic volumetric cardiac imaging. This approach assumes the relationship between the cardiac status and the ECG signal, such as the volume of the left ventricle as a function of the cardiac phase. Our knowledge-based cardiac CT algorithm is evaluated in numerical simulation and patient studies. In the patient studies, the cardiac status is estimated initially from ECG data and subsequently refined with reconstructed images. Our results demonstrate significant image quality improvements in cardiac CT studies, giving clearly better clarity of the chamber boundaries and vascular structures. In conclusion, this approach seems promising for practical cardiac CT screening and diagnosis.     

经鼻内镜下视神经管减压术的应用解剖

目的 通过对视神经管及其毗邻结构的研究,为临床视神经管减压术提供解剖学依据.方法 结构完整的成人头颈部标本12例,经红色乳胶灌注、10％的福尔马林固定,观察和测量如下指标:①观察视神经管的形态;②视神经管隆突的类型;③视神经管颅口、眶口及管中部的横径、纵径及横截面;④测量视神经管上、下、内、外侧壁的厚度;⑤视神经管内侧壁毗邻关系;⑥视神经管内眼动脉与视神经的位置关系.结果 视神经管由两口(颅口、眶口)和四壁(上壁、下壁、内侧壁、外侧壁)组成,其横截面积在眶口最大,管中部最窄;视神经管的内侧壁最薄,内侧壁的毗邻结构主要有3种类型:①前为同侧后筛窦、后为同侧蝶窦;②全为同侧蝶窦;③全为同侧后筛窦,眼动脉在视神经管的颅口、眶口分别以视神经的内下方和外上方多见.结论 本研究结果为经鼻内镜视神经管减压术提供了解剖学参数;当打开视神经管骨壁,鞘膜的切开选择内侧壁稍上方.     

The anatomical and clinical details of the pterygoid canal: a three-dimensional reconstructive virtual anatomic evaluation based on CT

Purpose

To delineate the pterygoid canal (PC) configuration and its position in relation to surrounding important anatomical landmarks using three-dimensional reconstructive technology based on CT for the Chinese.

Methods

The computerized tomography arteriography (CTA) data of 137 patients were retrospectively evaluated using neuroimaging three-dimensional reconstructive software. The morphological parameters of the PC as well as the spatial relationship and distance between the PC relative to internal carotid artery (ICA) and the foramen rotundum were evaluated.

Results

83.9 % of the PC can be identified by our neuroimaging three-dimensional reconstructive software. The mean distance from the PC to the ICA was 2.6 ± 1.2 mm. The mean distance between medial aspects of bilateral ICA was 19.6 ± 2.7 mm. The distal vertical and horizontal distances between the PC and foramen rotundum were 5.2 ± 3.2 and 6.1 ± 2.8 mm, respectively. All the proximal end of the PC were inferior-lateral to the ICA. The PC mainly (92.9 %) ran posteriorly with a medial to lateral direction. The distance from the PC to ICA was positively correlated with the distance between bilateral ICA and the distal diameter of the PC. The vertical distance between the PC and foramen rotundum was positively correlated with the length of the PC and the horizontal distance between the PC and foramen rotundum.

Conclusions

Understanding the configuration and spatial relationship of the PC may be helpful to improve the accuracy and safety of operation during the expanded transnasal endoscopic approaches to skull base. The three-dimensional reconstructive virtual anatomic technology may be a useful tool to delineate the PC configuration and its position to surrounding important anatomical landmarks.     

Decompression of the anterior thoracic spinal canal using a novel full‐endoscopic uniportal transthoracic retropleural technique—an anatomical feasibility study in human cadavers

Surgery for thoracic disc herniation and spinal stenosis is comparatively rare and often demanding. The goal is to achieve sufficient decompression without manipulating the spinal cord. Individual planning and various surgical techniques and approaches are required. This anatomical study examines the feasibility of a novel full‐endoscopic uniportal technique with a transthoracic retropleural approach for decompression of the anterior thoracic spinal canal. Operations were performed on three fresh adult cadavers. The endoscope used, from RIWOspine, Germany, has a shaft cross‐section of 6.9 × 5.9 mm and a 25° view angle. It contains an eccentric intraendoscopic working channel with a diameter of 4.1 mm. A transthoracic retropleural approach was used. The anatomical structures were dissected and the anterior thoracic epidural space was decompressed. The planned steps of the operation were performed on all cadavers. The transthoracic retropleural approach allowed the target region to be accessed easily. The anatomical structures could be identified and dissected. The anterior thoracic epidural space could be decompressed sufficiently. Using the uniportal full‐endoscopic operation technique with a transthoracic retropleural approach, the anterior thoracic epidural space can be adequately reached. This is a minimally invasive method with the known advantages of an endoscopic technique under continuous irrigation. The retropleural approach allows direct access. The instruments are available for clinical use and have been established for years in other operations on the entire spine. Clin. Anat. 31:716–723, 2018. © 2018 Wiley Periodicals, Inc.     

Visualisation of the vomerovaginal canal during endonasal transpterygoid approaches and CT imaging diagnosis

The vomerovaginal canal (VVC) and palatovaginal canal (PVC) are two canals that open forward to the posterior wall of the pterygopalatine fossa (PPF). Although the anatomy and computed tomography (CT) appearances of the PVC have been well studied, the VVC has been rarely reported, especially in endoscopic examinations. Some studies have even failed to distinguish the PVC from the VVC on CT images. The purpose of this study was to demonstrate the anatomy of the VVC on endoscopy and reveal its differences from the PVC, and to analyse the relative positions of the VVC, PVC, and pterygoid canal on CT images. Ten dry skull bases were studied to observe the structures involved in the formation of the VVC. Dissection of four cadaveric heads was performed to demonstrate the anatomy of the VVC on endoscopy. Coronal CT image analysis in 70 patients was conducted to evaluate the distances and relative positions between the VVC, PVC, and pterygoid canal. The PVC and VVC were also compared on axial CT images. The osteological study showed the top wall of the VVC was the antero‐inferior wall of the sphenoid sinus. The VVC may be a helpful landmark in endoscopic endonasal transpterygoid approaches. Steps and discrimination in the dissections of the VVC and PVC were described. The interval between the PVC and VVC could be observed on both coronal and axial CT images. The coronal CT images of patients showed differences in the positions and distances among the three canals at both the anterior and posterior apertures of the PVC. The VVC can be easily mistaken for the PVC if its existence is not suspected. The anatomical morphologies and trajectories of the VVC and PVC differed on both nasal endoscopy and CT. The existence of the VVC should be considered during surgery and CT diagnosis within this area.     

Anatomical variation of the nasal septum: Correlation among septal components

The nasal septum consists of multiple components with various developmental origins and is considered a mosaic structure. Few studies have focused on anatomical relationships among the components of the nasal septum, even though they are essential for clinical assessments of morphological abnormalities in the nasal septum. This study was performed to evaluate anatomical correlations among components of the nasal septum using computed tomography (CT) of the paranasal sinus. We studied images from CT scans of 168 paranasal sinuses collected at a secondary referral hospital between July 2008 and February 2009. The area of each component of the nasal septum was measured using median sagittal images of CT scans after three‐dimensional reconstruction using computer software. The area of the cartilaginous septum decreased with age, whereas the area of the total nasal septum remained constant. The area of the perpendicular plate of ethmoid increased with age at the expense of the area of the septal cartilage. Clin. Anat. 23:945–949, 2010. © 2010 Wiley‐Liss, Inc.     

Vortical flow in human elbow joints: a three‐dimensional computed tomography modeling study

The human elbow joint has been regarded as a loose hinge joint, with a unique helical motion of the axis during extension–flexion. This study was designed to identify the helical axis in the ulnohumeral joint during elbow extension–flexion by tracking the midpoint between the coronoid tip and the olecranon tip of the proximal ulna in a three‐dimensional (3D) computed tomography (CT) image model. The elbows of four volunteers were CT‐scanned at four flexion angles (0°, 45°, 90°, and 130°) at neutral rotation with a custom‐made holding device to control any motion during scanning. Three‐dimensional models of each elbow were reconstructed and a 3D ulnohumeral joint at 45°, 90°, and 130° was superimposed onto a fully extended joint (0°) by rotating and translating each 3D ulnohumeral joint along the axes. The midpoints of the olecranon and coronoid tips were interpolated using cubic spline technique and the dynamic elbow motion was plotted to determine the motion of the helical axis. The means and standard deviations were subsequently calculated. The average midpoint pattern of joint motion from extension to flexion was elliptical‐orbit‐like when projected onto a sagittal plane and continuously translated a mean 2.14 ± 0.34 mm (range, 1.83–2.52 mm) to the lateral side during elbow extension–flexion. In 3D space, the average midpoint pattern of the ulnohumeral joint resembles a vortical flow, spinning along an imaginary axis, with an inconsistent radius from 0° to 130° flexion. The ulnohumeral joint axis both rotates and translates during elbow extension–flexion, with a vortex‐flow motion occurring during flexion in 3D model analysis. This motion should be considered when performing hinged external fixation, total elbow replacement and medial collateral ligament reconstruction surgery.     

下颈椎椎弓根置钉偏差的CT多平面及三维重建研究

目的：通过颈椎CT多平面和三维重建资料的观测，了解下颈椎椎弓根螺钉置入的可行性，评价置钉偏差后的风险。方法：对8例非颈椎椎弓根病患者进行颈椎CT多平面和三维重建观察，对C3椎弓根内外径、内倾角及四壁皮质厚度行数据测量。结果：组成横突孔的四界不在同一高度同时出现，形成内界的椎弓根明显高于外界。CT示部分椎弓根外壁及横突孔前壁存在滋养血管孔（10％和8．8％）。C3椎弓根内壁厚（1．8±0．3）mm，，外壁厚（0．9±0．3）mm，上壁厚（1．3±0．4）mm，下壁厚（1．4±0．4）mm，外径（5．3±0．6）mm，内径（2．6±0．7）mm，内倾角（45．9±4．4）°。结论：下颈椎椎弓根内径小，外壁薄，椎弓根螺钉置入时，外壁容易穿破；椎弓根主体高于横突孔外界，椎弓根螺钉穿破外壁时，椎动脉可向外逃逸，减少损伤。