外科手术计算机辅助导航技术

外科手术计算机辅助导航即利用计算机图形图像技术对放射影像学资料进行处理 ,重建二维或三维的医学图像模型 ,同时结合各种空间定位技术 ,在医师的双眼、手术工具及患者的头部之间建立一个实时的环路 ,实现手术过程中器械位置的实时或准实时显示。我们综述了外科手术计算机辅助导航系统的发展历史和研究现状 (重点阐述了其系统结构和关键技术 ,包括空间定位技术、图像处理与显示技术、系统配准技术、头部定位技术等 (最后给出了手术导航系统的发展趋势     

计算机辅助导航模板辅助颈椎椎弓根置钉可行性研究

目的：利用逆向工程原理和快速成型技术,通过尸体标本试验验证导航模板可行性及准确性。方法：选取成年男性正常颈椎骨标本1具,范围从C1-7CT连续断层扫描数据集,采用Mimics 8．1三维重建颈椎数字解剖模型。分别在Geomagic studio9、Magics 9．5软件平台打开三维重建模型,定位三维参考平面,利用逆向工程（RE）原理寻找椎弓根的最佳进钉通道,提取椎板的表面解剖学形态,建立与椎体后部解剖学形态一致的反向模板,拟合模板和椎弓根孔道成定位模板,将导航模板通过激光快速成形技术制造出实物模型。将制作的实物模板和标本的椎板相吻合,利用导航模板的导航孔置入椎弓根螺钉,术后根据CT扫描评价椎弓根螺钉位置的准确性。结果：成功的设计并制作出与椎体后部解剖学结构一致的导航模板。术后CT扫描显示,模拟手术置入的14枚椎弓根钉位置均为Ⅰ类。结论：利用逆向工程原理和快速成型（RP）技术为颈椎弓根的定位、定向提供了一种新的方法,具有较好的应用前景。     

佐剂性关节炎大鼠滑膜巨噬细胞在关节破坏中的作用

目的:了解佐剂性关节炎(AA)大鼠滑膜巨噬细胞在关节破坏中的作用。方法:采用大鼠尾部皮内注射完全福氏佐剂建立AA模型,不同时点处死后后肢关节X线照片并进行放射学指数(RI)评分,膝关节滑膜石蜡切片HE染色和ED₁免疫组化染色及计数,分析RI与滑膜衬里层细胞层数及ED⁺₁细胞数的相关性。结果:AA大鼠滑膜衬里层细胞层数、衬里层及衬里下层ED⁺₁细胞数与RI水平呈显著正相关。结论:滑膜巨噬细胞在AA大鼠关节破坏中起重要作用。     

The nature of iron deposits in haemophilic synovitis

Summary Using a computerized electron-probe X-ray microanalytical technique to measure phosphorus/iron ratios we have defined the iron saturation of ferritin in vitro from prepared ferritin standards of known iron loading. This technique has been applied to the study of 5 haemophilic synovial membranes. At light microscope level the distribution and relationship of iron/ferritin were defined using Perls' reaction and an immunoperoxidase technique respectively. The synovia from all cases contained intra and extra-cellular deposits of Perls' positive material which were granular in nature in the most superficial synovial cells. There were increasing numbers of pheomorphic (1–12 µm diameter ovate bodies in the deeper synovial layers. Immunoperoxidase ferritin staining produced a strongly positive reaction in the granular material but the ovate bodies were negative with the exception of some peripheral staining. X-ray microanalysis showed the granular material to be highly iron saturated ferritin and the ovate bodies to be almost pure iron. We suggest that iron saturated ferritin in the synovial membrane could increase/perpetuate inflammation by promoting lipid peroxidation.     

Computer-assisted measurement of the thickness of biological structures

A method utilizing a digitizer tablet and microcomputer to determine the thickness of biological structures is described. The program for the determinations is written in BASIC. The accuracy and reproducibility of the method were confirmed using constructed test models and biological models. The system described is readily available and relatively low in cost.     

Is painless synovitis different from painful synovitis? A controlled,ultrasound, radiographic,clinical trial

OBJECTIVE:

This study compares the clinical, ultrasonography, radiography, and laboratory outcomes of painless and painful chronic synovitis in patients with established rheumatoid arthritis.

METHODS:

This cross-sectional study involved 60 patients with rheumatoid arthritis and synovitis in the metacarpophalangeal joints; 30 of the patients did not experience pain, and 30 had experienced pain for at least 6 months prior to the study. The radiocarpal, distal radioulnar, and metacarpophalangeal joints were evaluated using the ultrasound gray scale, power Doppler, and radiography. Past and present clinical and laboratory findings were also evaluated.

RESULTS:

There were no statistically significant differences between the groups for most of the outcomes. The group with pain scored worse on the disease activity indices (e.g., DAS 28 and SDAI), function questionnaires (HAQ and Cochin), and pinch strength test. A logistic regression analysis revealed that the use of an immunobiological agent was associated with a 3-fold greater chance of belonging to the group that experienced pain. The painless group had worse erosion scores in the second and fifth metacarpophalangeal with odd ratios (ORs) of 6.5 and 3.5, respectively. The painless group had more cartilage with grade 4 damage in the third metacarpophalangeal.

CONCLUSIONS:

The rheumatoid arthritis patients with both painless and painful synovitis exhibited similar disease histories and radiographic and ultrasound findings. However, the ultrasonography evaluation revealed worse scores in the second and fifth metacarpophalangeal of the synovitis patients who did not experience pain.     

Computer-assisted measurement of replicon autoradiograms

A system for obtaining measurements of the autoradiograms of DNA fibre replication units (replicons) using a computer-controlled microscope and scanner is described. Replicons can be measured faster, with greater objectivity, a higher data volume, and less operator error and fatigue than by manual methods.     

Computer-assisted 3D-reconstruction and statistics of the limbic system

Summary The hippocampal formation of eight perfusion-fixed human brains was examined using new methods according to stereotactic and morphometric principles (macrovibratome and computer-aided 3D reconstruction). The reconstructions form part of a neuroanatomical reference system (NeuRef). This reference system allows for 3D visualisation of the brain and its components on a computer graphic workstation, as well as for the presentation of the union set based on a neuroanatomical structure taken from this sample of brains. This retrievable knowledge of neurofunctional systems is important for the preoperative planning of neurosurgeons and the adjustment of radiotherapy.     

Computer-assisted 3D-reconstruction and statistics of the limbic system

A statistical method is described to show the distribution of neuroanatomical structures within a Cartesian coordinate system from any given number of examinations. The algorithm is based on polygons derived from the outlines of neuroanatomical structures in parallel canthomeatal-orientated cutting planes. These polygons are transformed in virtual voxels, rotated into the bicommissural coordinate system, and projected onto the three main planes of this coordinate system. Areas with the same probability for the structures examined are given in these planes. As an example this method is applied to the hippocampal formation and the results attained are shown.     

Quantitative determination of the diagnostic accuracy of the synovitis score and its components

Slansky E, Li J, Häupl T, Morawietz L, Krenn V & Pessler F
(2010) Histopathology 57 , 436–443
Quantitative determination of the diagnostic accuracy of the synovitis score and its components Aims: To assess the diagnostic accuracy of a three‐component synovitis score and to determine the relative contribution of each of its components to its overall discriminatory power. Methods and results: The synovitis score was determined in 666 synovial specimens: normal synovium, n = 33; post‐traumatic arthropathy (PtA), n = 29; osteoarthritis (OA), n = 221; psoriatic arthritis (PsA), n = 42; and rheumatoid arthritis (RA), n = 341. The discriminatory abilities of the score and its components were quantified with binary and multicategory receiver operating characteristic (ROC) analysis. The score differentiated all arthropathies accurately from normal tissue (area under the ROC curve, AUC: 0.87–0.98) and RA from OA or PtA (AUC: 0.85 for both), but could not distinguish well within pairs of inflammatory or degenerative arthropathies. AUCs of the intimal hyperplasia and stromal cellularity components correlated with the AUCs of the complete score markedly more strongly (r = 0.94 and 0.91, respectively) than the inflammatory infiltration component (r = 0.60). Multicategory ROC analysis ranked the score several‐fold higher than any of its components, and the components in the order stromal cellularity>intimal hyperplasia>infiltration. Conclusion: Combining three distinct histological parameters into a three‐component score produces greatly increased overall diagnostic power. The discriminatory ability of the score stems more from measuring proliferative than infiltrative aspects of synovitis.     

Synovitis score: discrimination between chronic low-grade and high-grade synovitis

AIMS: To standardize the histopathological assessment of synovial membrane specimens in order to contribute to the diagnostics of rheumatic and non-rheumatic joint diseases. METHODS AND RESULTS: Three features of chronic synovitis (enlargement of lining cell layer, cellular density of synovial stroma, leukocytic infiltrate) were semiquantitatively evaluated (from 0, absent to 3, strong) and each feature was graded separately. The sum provided the synovitis score, which was interpreted as follows: 0-1, no synovitis; 2-4, low-grade synovitis; 5-9, high-grade synovitis. Five hundred and fifty-nine synovectomy specimens were graded by two independent observers. Clinical diagnoses were osteoarthrosis (n=212), post-traumatic arthritis (n=21), rheumatoid arthritis (n=246), psoriatic arthritis (n=22), reactive arthritis (n=9), as well as controls (n=49) from autopsies of patients without joint damage. Median synovitis scores when correlated with clinical diagnoses were: controls 1.0, osteoarthritis 2.0, post-traumatic arthritis 2.0, psoriatic arthritis 3.5, reactive arthritis 5.0 and rheumatoid arthritis 5.0. The scores differed significantly between most disease groups, especially between degenerative and rheumatic diseases. A high-grade synovitis was strongly associated with rheumatic joint diseases (P<0.001, sensitivity 61.7%, specificity 96.1%). The correlation between the two observers was high (r=0.941). CONCLUSION: The proposed synovitis score is based on well-defined, reproducible histopathological criteria and may contribute to diagnosis in rheumatic and non-rheumatic joint diseases.     

Perspectives of Family Physicians on Computer-assisted Health-risk Assessments

Background

The firsthand experience of physicians using computer-assisted health-risk assessment is salient for designing practical eHealth solutions.

Objective

The aim of this study was to enhance understanding about computer-assisted health-risk assessments from physicians’ perspectives after completion of a trial at a Canadian, urban, multi-doctor, hospital-affiliated family practice clinic.

Methods

A qualitative approach of face-to-face, in-depth, semi-structured interviews was used. All interviews were audio recorded and field notes taken. Analytic induction and constant comparative techniques were used for coding and analyses. Interpretation was facilitated by peer audit and insights gained from the social exchange theoretical perspective.

Results

Ten physicians (seven female and three male) participated in the interviews. Three overarching themes emerged in relation to computer-assisted health-risk assessments: (1) perceived benefits, (2) perceived concerns or challenges, and (3) feasibility. Physicians unanimously acknowledged the potential of computer-assisted health-risk assessments to open dialogue on psychosocial health risks. They also appreciated the general facilitative roles of the tool, such as improving time-efficiency by asking questions on health risks prior to the consultation and triggering patients’ self-reflections on the risks. However, in the context of ongoing physician-patient relationships, physicians expressed concerns about the impact of the computer-assisted health-risk assessment tool on visit time, patient readiness to talk about psychosocial issues when the purpose of the visit was different, and the suitability of such risk assessment for all visits to detect new risk information. In terms of feasibility, physicians displayed general acceptance of the risk assessment tool but considered it most feasible for periodic health exams and follow-up visits based on their perceived concerns or challenges and the resources needed to implement such programs. These included clinic level (staff training, space, confidentiality) and organizational level (time, commitment and finances) support.

Conclusions

Participants perceived computer-assisted health-risk assessment as a useful tool in family practice, particularly for identifying psychosocial issues. Physicians displayed a general acceptance of the computer tool and indicated its greater feasibility for periodic health exams and follow-up visits than all visits. Future physician training on psychosocial issues should address physicians’ concerns by emphasizing the varying forms of “clinical success” for the management of chronic psychosocial issues. Future research is needed to examine the best ways to implement this program in diverse clinical settings and patient populations.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00385034","term_id":"NCT00385034"}}NCT00385034; http://clinicaltrials.gov/ct2/show/{"type":"clinical-trial","attrs":{"text":"NCT00385034","term_id":"NCT00385034"}}NCT00385034 (Archived by WebCite at http://www.webcitation.org/5pV8AGRgt)     

Prospective application of an expert system for the medical history of joint pain

Summary An expert system with 60 questions about medical history was developed for 32 rheumatologic diseases: 358 outpatients with joint complaints have been examined. The final diagnosis (result of symptoms, signs, and findings) was compared with the computer diagnoses and with the independently assumed diagnoses of the physician. The only source of information available to the physician was the medical history. Misinterpretation of the computer diagnoses occurred in 25.6% of cases compared with 21.5% of the physician. The final clinical diagnosis remained uncertain in 32.6% of cases. The error frequency of the expert system was influenced by the underlying disease, the certainty of the assumed diagnosis by the physician, the user experience in rheumatology, the number of questions asked, and the time of application before or after the doctor-patient contact. Of the errors 44% were produced because of information deficits of the computer using standardized questions. The information of the physician in the diagnostic process is quite different to that of the computer.Abbreviations XPS expert system - DIP distal interphalangeal joints - ARA American Rheumatology Association - OA osteoarthritis - Osteoarthritis g.j. osteoarthritis of greater joints     

计算机辅助外科手术中立体定位技术的研究进展

分析了计算机辅助手术中采用的各种定位技术,重点介绍了光学立位定位方法。最后指出计算机辅助手术中立体定位技术的研究和发展方向。     

标本采集时间对精液全自动分析各参数的影响

目的 为了了解精液分析中标本获取时间问隔对结果的影响，我们对44个健康受试者的精液进行了测试。方法 受试者48h内留取精液两次，采用伟力全自动精子分析仪对精液进行全自动分析。分别对已婚、未婚。24h、48h结果进行统计学分析。结果 两次取精中第二次精液量明显减少，且差异具有统计学意义。精子运动速度参数vsl、vd、vap，在已婚者中差异具有不同程度的统计学意义。精子密度、a级精子率两次差异均无统计学意义，而b级精子率和c级精子率两次差异均具有不同程度的统计学意义。结论 进行精液常规分析中应要求：取精间隔超过48h。并且最好每次检查前禁欲天数尽量保持一致，从而使检验结果具有可信和可比性。也有利于临床医生的诊断．及治疗效果的比较。     

Computer-assisted method for the analysis of postprandial gastrointestinal motility in conscious dogs

A fully automated system to quantify different parameters of gastrointestinal motility and gastroduodenal co-ordination in conscious dogs was designed and built around a personal technical computer (HP 9816). Online it performs sampling of contractions on four different sites of the digestive tract for two dogs simultaneously, data reduction, drift correction and storage of data on hard disk. Offine it performs baseline determination, peak detection, calculation of motility parameters such as amplitude and interval, plus co-ordination between gastric and duodenal motility and presentation of the results in both tabular and graphic form. To illustrate the possibilities and advantages of the computer analysis the early postprandial motor patterns for antrum, duodenum and jejunum were quantified during the first hour after administration of a small test meal.     

A computerised technique for morphometry and 3D reconstruction of embryological structures

Summary In the last decade we have witnessed the development of software technology capable of image analysis and morphometry [1, 8–12]. Although these methods are sometimes difficult to master in a practical sense, they are tremendously efficient and precise when applied to the study and measurement of developing biological structures, particularly in the field of embryology. In this study we describe the application on human embryos of an image analyzing system that enables one to perform quantitative analyses of the morphology and size of developing organs and structures as well as their ultimate three-dimensional reconstruction (3DR).

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Technique informatique de morphométrie et de reconstruction tridimensionnelle des structures embryonnaires

Résumé Au cours de cette dernière décennie nous avons assisté au développement de logiciels adaptés à l'analyse de l'image et à la morphométrie. Bien que ces techniques soient parfois difficiles à maîtriser, elles sont particulièrement efficaces et précises dans l'étude du développement des structures biologiques, et particulièrement dans le domaine de l'embryologie. Dans ce travail, nous rapportons l'application aux embryons humains d'un système d'analyse d'image, qui autorise aussi bien une analyse morphologique quantitative des organes et des structures en développement, que leur reconstruction tridimensionnelle ultérieure.

     

Mapping the sequence of contraction of the canine left ventricle

A method has been developed to map the sequence of contraction as measured at the epicardial surface of the anterior free wall of the canine left ventricle during sinus rhythm and electrical stimulation of the ventricle. In an area of 35×45 mm, 40–60 white markers were attached to the epicardial surface. The motion of the markers was recorded on video and analysed off-line by computer. In an array of 35 regions, regional surface deformation and epicardial fibre strain were calculated from the motion of the markers. Between all adjacent regions, the differences in timing of contraction were determined by cross-correlation of the related fibre strain signals. A map of the time sequence of contraction has been calculated so that the sum of the squares of the deviations between time intervals of the map and the measurements was minimised. If individual correlation coefficients were found to be less than 0.85, the related time difference was discarded from the analysis. If more than 25% of the time differences were discarded because of this reason, the whole map was obtained by determining time of the negative peak of the second time derivative in the early phase of contraction. The accuracy in time marking was sufficient (±7 ms), as compared to the time differences over the epicardial surface, which were found to be on the average between 10 and 80 ms in case of sinus rhythm and electrical stimulation of the right ventricular outflow tract, respectively.     

Proposal of a morphologic bone marrow response score for imatinib mesylate treatment in chronic myelogenous leukemia

Cytogenetic and molecular analyses are essential disease-monitoring parameters in chronic myelogenous leukemia (CML) treated with imatinib. However, a bone marrow morphologic response has not been defined. We reviewed bone marrow histology and cytology of 39 imatinib-treated patients with CML over 49 weeks and introduced a morphologic response score. A significant positive correlation with a complete cytogenetic response was shown for absence of dry tap (P = .04) and abnormal megakaryocytes (P < 0.001), normalization of cellularity (P = .001) and reduction of fibrosis (P = .01), myelopoiesis:erythropoiesis index (P = .001), blast (P = .001) and basophil count (P < 0.001). The morphologic score integrating these parameters showed an early and late correlation with cytogenetic response. In conclusion, morphologic criteria for complete cytogenetic response in patients with CML treated with imatinib can be defined. Persistent high-level morphologic abnormalities herald early on a high likelihood to fail treatment and call for more intense or alternative therapy.