The thin sectional anatomy of the temporal bone correlated with multislice spiral CT

The aim of this study was to explore the method for obtaining the thin sectional anatomy data of the adult temporal bone and study the fine structures using this method. Three fresh adult cadaveric heads were scanned with multi-slice computer tomography (MSCT) centered on petrous bones. The CT images of 0.6 mm were obtained by multi-planar reformation (MPR). The slices of 0.1 mm were shaved off the specimen in the axial direction with the numerical control milling machine after being embedded and frozen, pictures of which were taken by the digital camera and saved in the computer. The thin axial sectional anatomic structures of the intra-temporal were investigated and correlated with MPR images. Via the comparison, fifty micro-anatomic structures of the temporal bone that can’t be delineated clearly or missed in the thick sections were evaluated. The anatomical details of the temporal bone can be clearly delineated in MSCT in sub-millimeter and were identical to those in sectional anatomy images. This method can supply anatomical details that had been missed or overlooked for imaging diagnosis and surgical anatomy.     

Three-dimensional imaging of the petrous bone for the middle fossa approach to the internal acoustic meatus: an experimental study

The goal of this study was to highlight the feasibility of creating three-dimensional (3D) pictures of the petrous bone from a routine CT examination which can be used for a middle fossa approach to the internal acoustic meatus, in order to secure this operation. The surgical aim is to reach the roof of the internal acoustic meatus directly without injuring the adjacent functional structures of the petrous bone. Two heads of embalmed cadavers were scanned every millimeter with a slice thickness of 1 mm centered on the petrous bones. The horizontal reference was the Frankfurt line and the frontal and sagittal planes were perpendicular to this line. This method is similar to routine examinations for surgical patients. The pictures were first loaded on an optical disk, then into a computer (Silicon Graphics System). Amira software was used to create 3D pictures. The anatomy of the temporal bone could easily be identified, notably the surgical landmarks of the middle fossa approach. Three-dimensional computer-assisted imaging can reveal the anatomy of the petrous bone in a realistic view. The main anatomic structures for a middle fossa approach can be recognized easily. This realistic view may be very useful for surgeons, and 3D images deserve to be developed further.     

Anatomical informatics: Millennial perspectives on a newer frontier

One of the most ancient of sciences, anatomy has evolved over many centuries. Its methods have progressively encompassed dissection instruments, manual illustration, stains, microscopes, cameras and photography, and digital imaging systems. Like many other more modern scientific disciplines in the late 20th century, anatomy has also benefited from the revolutionary development of digital computers and their automated information management and analytical capabilities. By using newer methods of computer and information sciences, anatomists have made outstanding contributions to science, medicine, and education. In that regard, there is a strong rationale for recognizing anatomical informatics as a proper subdiscipline of anatomy. A high-level survey of the field reveals important anatomical applications of computer sciences methods in imaging, image processing and visualization, virtual reality, modeling and simulation, structural database processing, networking, and artificial intelligence. Within this framework, computational anatomy is a developing field focusing on data-driven mathematical models of bodily structures. Mastering such computer sciences and informatics methods is crucial for new anatomists, who will shape the future in research, clinical knowledge, and teaching.     

A short course of dissection for second-year medical students at the School of Medicine of Padova

A "Short course of dissection" was introduced in 1999 for the second-year medical students at the University of Padova. The course aims to offer a direct experience of practical anatomy despite a shortage of time for anatomy courses and lack of availability of cadavers. The course is optional and is planned for 40 students, subdivided into eight working groups. It consists of five sessions on the following topics: the viscera of the male pelvis; the viscera of the female pelvis; the kidney, the testis and spermatic cord; the thorax and abdomen; the brain. Each session lasts 3 hours and is organized as follow: (A) Theory: Teacher: concise review of the systematic and topographic anatomy of the selected topic (20 min); Students: analysis of a dissection guide (20 min). (B) Practice: Students: identification of the viscera and vascular and nervous structures, through inspection and palpation (15 min); step-by-step dissection following the worksheet (80 min); presentation of the visceral blocks as prosections under a closed-circuit telecamera (anatomical variability) (30 min); Teachers and students: three-dimensional conceptualization tests (15 min). At the end of the 2000 and 2001 courses, a questionnaire was administered to the students and the results confirm the usefulness of dissection for developing a three-dimensional knowledge of anatomy. In our opinion the main guidelines in planning a short course of dissection are: (1) selection of the topics, aimed at allowing experience of the gross anatomy of single viscera, fascia and serosa as well as the evaluation of the topographical relationships between parts of different systems including the local vessels and nerves; (2) preparation of a worksheet, presenting in 10-15 points concise instructions for the step-by-step progression from inspection to palpation and dissection of the anatomical structures of the visceral block; (3) direct dissection, brief and selective, by students; (4) clinical correlation; (5) motivational teachers, who stimulate the active involvement of students in "learning by doing" and also "learning how to do".     

国人肛门括约肌的数字化三维重建

目的通过人体连续横断面图像数据集和计算机三维重建形成数字化的肛门括约肌。方法将人体连续横断面图像数据集的括约肌部分,通过3D-MAX软件建立成数字立体的肛门括约肌三维图像。结果建立了我国第一份肛门括约肌的数字立体模型,并渲染、导出顶视图,前视图,侧视图及任意的剖面图。结论为研发集局部解剖学和肛肠科疾病于一体的教学软件及模拟手术程序,提供基础平台。     

Digital processing of high-energy photon beam images

The potentialities of digital megavoltage radiation field images for image quality improvement and evaluation of patient treatment setup errors are investigated. A treatment verification film is digitized with a densitometer and a treatment planning computer. The 256 X 256 picture matrix is displayed on a viewing console of a computer tomograph. The results of some processed pictures show an improved visibility of anatomical structures, which is of importance for comparison of the treatment beam images with the corresponding localization radiograph made on the simulator. In addition, automated techniques for comparison of irradiation and simulation setup are now possible.     

中国人颅骨三维重建

目的探讨中国人颅骨三维重建的方法和意义。方法对冰冻颅脑行间隔1mm断层切片,数码摄影,用自制软件对含颅骨的层面行轮廓线的提取,并进行三维重建。结果重建后的颅骨形态结构逼真,可赋予不同的颜色进行单独显示、任意搭配显示和整体显示,还可在三维空间位置上绕任意轴进行任意角度旋转。结论本方法对于在计算机二维平面上进行颅骨的三维重建是可行的,软件运行可靠,重建图象为教学及外科手术提供参考资料。     

Segmentation and Surface Reconstruction of the Detailed Ear Structures,Identified in Sectioned Images

The structure of the ear, which intervenes between gross anatomy and histology in size, can be best understood by means of three‐dimensional (3D) surface models on a computer. Furthermore, surface models are the source of interactive simulation for clinical trials, such as tympanoplasty. The objective of this research was to elaborate the surface models of detailed ear structures, which contribute to learning anatomy or the practice of otology. We produced sectioned images of a cadaver head (pixel size, 0.1 mm; 48‐bit color). In the sectioned images, the external, middle, and internal ear structures and other related components were delineated on Photoshop to acquire segmented images at 0.5‐mm intervals. Segmented images of each structure were stacked, and the surface was reconstructed to generate a 3D‐surface model on commercial software. Thirty surface models showed fine ear topographic anatomy (e.g., semicircular ducts), as expected. Herein, we present the corresponding sectioned images, segmented images, and surface models of ear structures that will be released together. It is hoped that these image data will stimulate the development of medical simulations. The efficient technique of segmentation and surface reconstruction enables the manufacture of surface models from other serial images (e.g., CTs and MRIs). Anat Rec, 2011. © 2011 Wiley‐Liss, Inc.     

Construction of a 3-D anatomical model for teaching temporal lobectomy

Although we live and work in 3 dimensional space, most of the anatomical teaching during medical school is done on 2-D (books, TV and computer screens, etc). 3-D spatial abilities are essential for a surgeon but teaching spatial skills in a non-threatening and safe educational environment is a much more difficult pedagogical task. Currently, initial anatomical knowledge formation or specific surgical anatomy techniques, are taught either in the OR itself, or in cadaveric labs; which means that the trainee has only limited exposure. 3-D computer models incorporated into virtual learning environments may provide an intermediate and key step in a blended learning approach for spatially challenging anatomical knowledge formation. Specific anatomical structures and their spatial orientation can be further clinically contextualized through demonstrations of surgical procedures in the 3-D digital environments. Recordings of digital models enable learner reviews, taking as much time as they want, stopping the demonstration, and/or exploring the model to understand the anatomical relation of each structure. We present here how a temporal lobectomy virtual model has been developed to aid residents and fellows conceptualization of the anatomical relationships between different cerebral structures during that procedure. We suggest in comparison to cadaveric dissection, such virtual models represent a cost effective pedagogical methodology providing excellent support for anatomical learning and surgical technique training.     

国人脑室的数字化研究

目的探讨运用计算机和超薄断面图像来计算脑室参数的方法。方法通过对尸头连续水平切片,获取间距1mm的连续断面图像240张,对图像进行对位处理,确立三维坐标原点,建立三维坐标系,通过Photoshop7.0软件的内在功能和一些常用数学公式对脑室相关参数进行测量。结果获得脑室系统相关参数。结论这是一种简洁而精确的测量方法,而且操作具有可重复性,与传统的测量方法相比较具有明显的优越性。     

Development and implementation of a web-enabled 3D consultation tool for breast augmentation surgery based on 3D-image reconstruction of 2D pictures

Background

Producing a rich, personalized Web-based consultation tool for plastic surgeons and patients is challenging.

Objective

(1) To develop a computer tool that allows individual reconstruction and simulation of 3-dimensional (3D) soft tissue from ordinary digital photos of breasts, (2) to implement a Web-based, worldwide-accessible preoperative surgical planning platform for plastic surgeons, and (3) to validate this tool through a quality control analysis by comparing 3D laser scans of the patients with the 3D reconstructions with this tool from original 2-dimensional (2D) pictures of the same patients.

Methods

The proposed system uses well-established 2D digital photos for reconstruction into a 3D torso, which is then available to the user for interactive planning. The simulation is performed on dedicated servers, accessible via Internet. It allows the surgeon, together with the patient, to previsualize the impact of the proposed breast augmentation directly during the consultation before a surgery is decided upon. We retrospectively conduced a quality control assessment of available anonymized pre- and postoperative 2D digital photographs of patients undergoing breast augmentation procedures. The method presented above was used to reconstruct 3D pictures from 2D digital pictures. We used a laser scanner capable of generating a highly accurate surface model of the patient’s anatomy to acquire ground truth data. The quality of the computed 3D reconstructions was compared with the ground truth data used to perform both qualitative and quantitative evaluations.

Results

We evaluated the system on 11 clinical cases for surface reconstructions and 4 clinical cases of postoperative simulations, using laser surface scan technologies showing a mean reconstruction error between 2 and 4 mm and a maximum outlier error of 16 mm. Qualitative and quantitative analyses from plastic surgeons demonstrate the potential of these new emerging technologies.

Conclusions

We tested our tool for 3D, Web-based, patient-specific consultation in the clinical scenario of breast augmentation. This example shows that the current state of development allows for creation of responsive and effective Web-based, 3D medical tools, even with highly complex and time-consuming computation, by off-loading them to a dedicated high-performance data center. The efficient combination of advanced technologies, based on analysis and understanding of human anatomy and physiology, will allow the development of further Web-based reconstruction and predictive interfaces at different scales of the human body. The consultation tool presented herein exemplifies the potential of combining advancements in the core areas of computer science and biomedical engineering with the evolving areas of Web technologies. We are confident that future developments based on a multidisciplinary approach will further pave the way toward personalized Web-enabled medicine.     

三维重建上肢解剖结构的计算机模拟手术

探索三维重建后计算机模拟手术过程的实现。将上肢新鲜标本经ＣＴ扫描后连续切片,把ＣＴ图像和大体断面图像同时输入计算机,用Ｂｏｒｌａｎｄ Ｃ＋＋语言编制三维重建和模拟手术程序,建立上肢三维解剖数据模型,将临床实际手术操作过程转化为计算机可接受的指令,实现模拟手术操作。结果表明：上肢模拟手术可分三段进行,手术部位及切口方向可任意选择,逐层“切开”并三维显示,因此,模拟手术系统可运用于手术方案的设计、选择     

Event-Related Potentials and Recognition Memory For Pictures and Words: The Effects of Intentional and Incidental Learning

Event-related potentials were recorded under conditions of intentional or incidental learning of pictures and words, and during the subsequent recognition memory test for these stimuli. Intentionally learned pictures were remembered better than incidentally learned pictures and intentionally learned words, which, in turn, were remembered better than incidentally learned words. In comparison to pictures that were ignored, the pictures that were attended were characterized by greater positive amplitude frontally at 250 ms and centro-parietally at 350 ms and by greater negativity at 450 ms at parietal and occipital sites. There were no effects of attention on the waveforms elicited by words. These results support the view that processing becomes automatic for words, whereas the processing of pictures involves additional effort or allocation of attentional resources. The N450 amplitude was greater for words than for pictures during both acquisition (intentional items) and recognition phases (hit and correct rejection categories for intentional items, hit category for incidental items). Because pictures are better remembered than words, the greater late positive wave (600 ms) elicited by the pictures than the words during the acquisition phase is also consistent with the association between P300 and better memory that has been reported.     

Time course of attentional modulations on automatic emotional processing

In a previous study using event-related potentials (ERPs) [S. Doallo, S. Rodríguez Holguín, F. Cadaveira, Attentional load affects automatic emotional processing: evidence from event-related potentials, Neuroreport 17 (2006) 1797-1801], we reported that differential responses to unattended peripheral affective pictures, as reflected by N1-P2 modulations at posterior regions, are modulated by attentional load at fixation. Here, new analyses of these data were performed to evaluate whether a sustained, broadly distributed, negative shift in the unattended pictures ERP waveforms, which displayed larger amplitudes for emotional stimuli, reflects an additional differential response to the emotional content. Under low-load conditions, unpleasant (versus neutral) pictures elicited greater negativities in the 80-140 ms latency range over frontocentral sites and more centroparietally distributed from 200 to 280 ms. These findings provide further evidence of the time course of emotional processing at unattended locations and its modulation by attentional load.     

探索建立颅脑MRI图像、断层标本图像及三维重建图像的对比数据模型

目的利用计算机图像处理系统对颅脑主要重要结构进行三维成像,探索建立1套正常颅脑部MRI图像、断层标本及三维重建图像的数据对照计算机模型,为影像诊断及颅脑部手术定位提供形态依据。方法利用Microsoft Visual Studio将获得的MRI图像、断层标本图像及重建的三维图像建立数据模型。结果建立的数据模型提供了颅脑部正常解剖学影像学对比特点,构建了主要结构的三维立体模型图像,使抽象结构数字化、立体化、可视化,有助于对人脑的理解。结论本数据模型把颅脑结构的三维图像结合到标本MRI的对比图中,有利于初次接触颅脑断层的初学者。     

Digital processing of microradiographic and fluorochromic images from bone biopsy

Bone biopsy is an essential technique for the diagnosis of metabolic bone disease and the skeletal response to remedial therapeutic maneuvers. Among many approaches in analyzing the biopsy specimen, the imaging technique offers the greatest potential. The objective of this paper is to describe the methodologies developed for digital processing of microradiographic and fluorochromic images from bone biopsy. This procedure requires a microscope with conventional and ultraviolet illuminations, a vidicon camera with three color filters, a general purpose image processing system with three image memories, a digital computer with some specially tailored software programs. A good specimen preparation from bone biopsy is a prerequisite in assuring the success of the method. The methodology for processing the microradiographs is based on a completely developed procedure of black and white image processing. Production run is in progress. The methodology for processing the fluorochromic images is based on true color imaging, although the procedure is still preliminary, early results obtained so far are promising.     

Microsurgical anatomy of the abducens nerve

The aim of this study is to demonstrate and review the detailed microsurgical anatomy of the abducens nerve and surrounding structures along its entire course and to provide its topographic measurements. Ten cadaveric heads were examined using ×3 to ×40 magnification after the arteries and veins were injected with colored silicone. Both sides of each cadaveric head were dissected using different skull base approaches to demonstrate the entire course of the abducens nerve from the pontomedullary sulcus to the lateral rectus muscle. The anatomy of the petroclival area and the cavernous sinus through which the abducens nerve passes are complex due to the high density of critically important neural and vascular structures. The abducens nerve has angulations and fixation points along its course that put the nerve at risk in many clinical situations. From a surgical viewpoint, the petrous tubercle of the petrous apex is an intraoperative landmark to avoid damage to the abducens nerve. The abducens nerve is quite different from the other nerves. No other cranial nerve has a long intradural path with angulations and fixations such as the abducens nerve in petroclival venous confluence. A precise knowledge of the relationship between the abducens nerve and surrounding structures has allowed neurosurgeon to approach the clivus, petroclival area, cavernous sinus, and superior orbital fissure without surgical complications. Clin. Anat. 25:1030–1042, 2012. © 2012 Wiley Periodicals, Inc.     

《生物医学信号处理》实验演示软件开发

由于医学信号的随机性、广泛性和复杂性,使得生物医学信号处理课程的教学具有一定的挑战。为了提高教学效果,本文结合实际的教学过程,探讨了关于该课程实验演示软件制作的思路、方法、目的,指出如何把医学信号处理中抽象的算法用演示工具直观的表达出来。     

Erotic and disgust-inducing pictures--differences in the hemodynamic responses of the brain

The aim of this fMRI study was to explore brain structures that are involved in the processing of erotic and disgust-inducing pictures. The stimuli were chosen to trigger approach and withdrawal tendencies, respectively. By adding sadomasochistic (SM) scenes to the design and examining 12 subjects with and 12 subjects without sadomasochistic preferences, we introduced a picture category that induced erotic pleasure in one sample and disgust in the other sample. Since we also presented neutral pictures, all subjects viewed pictures of four different categories: neutral, disgust-inducing, erotic, and SM erotic pictures. The analysis indicated that several brain structures are commonly involved in the processing of disgust-inducing and erotic pictures (occipital cortex, hippocampus, thalamus, and the amygdala). The ventral striatum was specifically activated when subjects saw highly sexually arousing pictures. This indicates the involvement of the human reward system during the processing of visual erotica.