The role of computed tomography in adult post-mortem examinations: an overview

Radiology has been a part of autopsy practice since just after the discovery of X-rays. Today it remains an important investigative tool although the radiological modalities utilized are changing. The role of post-mortem cross-sectional imaging is gaining acceptance across the world in both natural and unnatural death investigation. This symposium paper provides an overview of the history of the introduction of computed tomography into post-mortem practice, the areas where it is currently been used in practice and problems encountered in relation to its use.     

Exchanging information: current United Kingdom developments in the infrastructure to support post-mortem imaging

Through joint working across the Home Office, Ministry of Justice and Department of Health the United Kingdom (UK) has developed a single programme of research and development in the field of less invasive autopsy, forensic and mass fatality imaging. By supporting research and development within these fields the UK has developed an outline for a national core training programme in this field along with the development of the National Forensic Image Management System (FiMag). This symposium paper is a brief overview of this development.     

Teaching and examining for post-mortem CT-scanned autopsies

The traditional style of autopsy teaching and training requires adaptation for the evolving practice of post mortem radiology, with the pathology trainee learning to interpret radiological diagnostic data mapped against the ante mortem information and external examination. The potential benefits of post mortem radiology require cautious evaluation in the training environment, as some pathologies are not well seen by post mortem computerized tomography (PMCT). There is also the trap of some pathology being readily found, which is not relevant to the cause of death. This article debates the standard format of the PMCT report and how one should judge if additional testing or invasive autopsy are required. The article also considers what is being sought in those facing examination with PMCT-based questions.     

Post-mortem MR and CT imaging in fetuses,newborns and children: an evidenced based approach

There is insufficient evidence in the published literature to support the use of post-mortem MR imaging (MRI) as an alternative for conventional non-forensic autopsy in fetuses, newborns and children. Large prospective studies evaluating the accuracy of post-mortem MR imaging in a rigorous and blinded way are now nearing completion and the results are expected in 2011. Less-invasive autopsies by post-mortem MR imaging may have major effect in resurrecting consented autopsy rates; however an evidenced based and systematic approach towards less-invasive autopsy process is mandatory to ensure that the post-mortem data remains accurate and credible. Here we summarize the current evidence, ongoing research and future directions for less-invasive autopsy process in the United Kingdom. A joint effort between clinicians, radiologists, pathologists, parent groups and funding bodies is essential for successful implementation of less-invasive autopsy, in the UK.     

The role of computed tomography and magnetic resonance imaging in the investigation of natural death

Public distaste for the traditional autopsy combined with disquiet about the variable quality of the coroner’s post-mortem have led to increasing pressure to find a less invasive alternative. There have been previous studies using computed tomography (CT) and magnetic resonance imaging (MRI) to determine cause of death but there is very little evidence of the accuracy or reproducibility of these techniques in non-forensic cases. In 2006 the Department of Health funded a validation study of post-mortem imaging in adults which is due to report this year. Preliminary results suggest that, if a confident imaging (MR and CT) diagnosis of the cause of death is made, the major error rate is close to that of clinical death certificates. There are major weaknesses in diagnosis of coronary heart disease and pulmonary thromboemboli on imaging. These weaknesses will need to be overcome if imaging is to replace the invasive post-mortem or systematic errors in mortality statistics will result.     

The body recovered from water: considerations for an approach to the non-suspicious post-mortem examination

Bodies from the water are not commonly encountered in everyday practice, either by the forensic pathologist or by the coroner's pathologist. The body recovered from water can pose particular difficulty to the unsuspecting pathologist, especially if there is evidence of decomposition or if the body is injured. However, it is important to have an understanding for the necessity of the post-mortem examination and to identify those findings which may support drowning or immersion, in the absence of other relevant findings. Limited autopsy has no place in the pathological examination of a body recovered from water as arriving at a conclusion of drowning relies on excluding all other causes. Currently, it is recognized that non-invasive autopsy is not ideal in diagnosing death in cases recovered from water and therefore conventional invasive post-mortem examination with histology and toxicology remains paramount.     

High throughput adult cadaver axial imaging: service logistics and requirements

It remains unknown to date the extent of the potential role of computed tomography (CT) and magnetic resonance imaging (MRI) in autopsy practice in the United Kingdom (UK). If CT and/or MRI were accepted to have a role beyond that already been undertaken within the UK and implemented on a national high throughput scale, what impact would it have upon the National Health System (NHS) where, in the UK, the majority of mortuary facilities and practitioners work? This symposium paper explores the logistics, personnel and facilities that may be required to assist those contemplating developing such a provision of service. The discussion presented is based upon the concept that all cadavers normally subjected to invasive medico-legal (coroner’s) autopsy would be imaged following receipt at an NHS hospital located mortuary. It is based on the experience of the East Midlands Forensic Pathology Unit and Imaging Department, University Hospitals of Leicester in examining cadavers using CT within the NHS where all of these problems have been encountered previously.     

Graphene oxide-BaGdF5 nanocomposites for multi-modal imaging and photothermal therapy

By using a solvothermal method in the presence of polyethylene glycol (PEG), BaGdF₅ nanoparticles are firmly attached on the surface of graphene oxide (GO) nanosheets to form the GO/BaGdF₅/PEG nanocomposites. The resulting GO/BaGdF₅/PEG shows low cytotoxicity, positive magnetic resonance (MR) contrast effect and better X-ray attenuation property than Iohexol, which enables effective dual-modality MR and X-ray computed tomography (CT) imaging of the tumor model in vivo. The enhanced near-infrared absorbance, good photothermal stability and efficient tumor passive targeting of GO/BaGdF₅/PEG result in the highly efficient photothermal ablation of tumor in vivo after intravenous injection of GO/BaGdF₅/PEG and the following 808-nm laser irradiation (0.5 W/cm²). The histological and biochemical analysis data reveal no perceptible toxicity of GO/BaGdF₅/PEG in mice after treatment. These results indicate potential application of GO/BaGdF₅/PEG in dual-modality MR/CT imaging and photothermal therapy of cancers.     

早期股骨头坏死影像学诊断的成本效益分析

目的:探讨早期成人股骨头缺血坏死(femoralheadnecrosis,FHN)的MR、CT、SPECT和X线平片4种影像学检查的成本效益比,寻找较好的成本效益的检查方法.方法:分析和总结82例129髋随访和病理证实或具有典型影像学表现的早期(ARCOI~II期)成人FHN病人的髋关节影像学资料.全部病例均同期行MRI、CT、单光子发射计算机体层摄影(singlephotonemissioncomputedtomography,SPECT)和X线平片检查.采用成本效果分析法(cost-effectivenessanalysis,CEA),对4种影像学检查诊断效率研究中的数据进行分析,比较其正确检出费用(costofaccuratediagnosis,CAD).结果:4种影像学检查方法的诊断差异有显著性意义.早期诊断成人FHN的检出费用最低的是X线平片,对于X线平片确诊组和诊断可疑组,MRI检出费用并无太大变化,而CT费用最低;对于X线平片诊断阴性组,MRI诊断的敏感性和准确性综合比较高于CT和SPECT,且诊断费用也最低.结论:X线适合早期股骨头坏死的筛选,而MRI诊断的敏感性和准确性综合比较高于CT和SPECT,而且应当作为X线诊断阴性的可疑股骨头坏死患进一步诊断的首选..     

继发于恶性肿瘤的腹膜后纤维化临床和影像学特征分析

 摘要： 目的 探讨继发于恶性肿瘤的腹膜后纤维化（RPF, Retroperitoneal Fibrosis）的临床和影像学特征。 方法 分析我院1992年7月~2010年1月各科住院的RPF患者共106例,以其中继发于恶性肿瘤的8例RPF为研究对象,收集患者的临床资料并进行规律随访。 结果 8例恶性RPF中男性5例,女性3例,平均年龄59.6岁。原发肿瘤中生殖系统肿瘤4例,消化系统肿瘤2例,血液系统肿瘤及恶性神经鞘瘤各1例,其中1例同时患胃癌和膀胱癌。恶性RPF的临床症状与良性者比较并无特异,诊断主要依据影像学和病理。恶性RPF计算机X射线断层造影（CT）的特点：通常范围更广泛,肿物体积更大,包绕的腹主动脉、下腔静脉可发生背离脊柱方向的移位,输尿管可能发生向外侧移位;肿物边缘多呈结节或分叶状;肿物的中心多偏向髂血管方向。CT还可评价疗效和提示预后,病理学为最终确诊依据。 结论 恶性RPF临床症状无特异性,但影像学表现有一定特征,有鉴别诊断意义。     

Novel imaging approaches in adult asthma and their clinical potential

Currently, imaging in asthma is confined to chest radiography and CT. The emergence of new imaging techniques and tremendous improvement of existing imaging methods, primarily due to technological advancement, has completely changed its research and clinical prospects. In research, imaging in asthma is now being employed to provide quantitative assessment of morphology, function and pathogenic processes at the molecular level. The unique ability of imaging for non-invasive, repeated, quantitative, and in vivo assessment of structure and function in asthma could lead to identification of ‘imaging biomarkers’ with potential as outcome measures in future clinical trials. Emerging imaging techniques and their utility in the research and clinical setting is discussed in this review.     

光学相干成像技术对神经及脑的成像

神经与脑的成像作为最具挑战性的课题之一,得到越来越多的关注.对神经与脑部的成像,能够对神经系统及脑部形态、结构以及功能量化,不仅有助于更加深入地了解脑及神经系统.并且可以提高临床诊疗的效率.光学相干成像技术(OCT)是一种新型的成像技术,已被广泛用于生物与医学领域.光学相干成像技术在对神经及脑的成像研究中,最为人们所关注,其该技术的发展也最为迅速.该技术为解决神经及脑的成像问题提供了新的思路和方法,其发展潜力还有待发掘.概述了光学相干成像技术在神经和脑成像领域的最新技术以及成果,讨论了其在神经和脑成像领域的优缺点以及其未来的发展趋势.     

Prussian blue coated gold nanoparticles for simultaneous photoacoustic/CT bimodal imaging and photothermal ablation of cancer

The combination of CT imaging and photoacoustic (PA) imaging represents not only high resolution and ease of forming 3D visual image for locating tissues of interest, but also good soft tissue contrast and excellent high sensitivity, which is very beneficial to the precise guidance for photothermal therapy (PTT). The near infrared (NIR) absorbing Au nanostructures take advantages to operate as a CT contrast agent due to high absorption coefficient of X-ray and outstanding biocompatibility, but show obvious deficiency for PA imaging and PTT because of low photostability. Attacking this problem head on, the Au nanoparticles (NPs) were coated with Prussian blue (PB) which is a typical FDA-approved drug in clinic for safe and effective treatment of radioactive exposure. The obtained core/shell NPs of Au@PB NPs of 17.8 ± 2.3 nm were found to be an excellent photoabsorbing agent for both PTT and PA imaging due to high photostability and high molar extinction coefficient in NIR region. Their gold core of 9.1 ± 0.64 nm ensured a remarkable contrast enhancement for CT imaging. Through a one-time treatment of NIR laser irradiation after intravenous injection of Au@PB NPs, 100 mm³ sized tumors in nude mice could be completely ablated without recurrence. Such versatile nanoparticles integrating effective cancer diagnosis with noninvasive therapy might bring opportunities to future cancer therapy.     

Lanthanide-based nanocrystals as dual-modal probes for SPECT and X-ray CT imaging

Applications of lanthanide-based nanoparticles for bioimaging have attracted increasing attention. Herein, small size PEG-EuOF:¹⁵³Sm nanocrystals (∼5 nm) (PEG = poly(ethylene glycol)bis(carboxymethyl)ether) combined with the radioactive and X-ray absorption properties were synthesized. The distribution of the PEG-EuOF nanocrystals in living animals was studied by ex vivo radioassay, inductively coupled plasma-atomic emission spectrum (ICP-AES) analysis and in vivo SPECT imaging, which indicated that the small size PEG-EuOF:¹⁵³Sm had long blood retention time (blood half-life (t_1/2) reach to 4.65 h) and were eliminated significantly through biliary/gastrointestinal pathway in vivo. Meanwhile, benefiting from the high attenuation ability of Eu, the small size PEG-EuOF was successfully applied for lymph node CT imaging, extending the bio-applications of these small nanocrystals. The results of cytotoxicity and in vivo toxicity also showed that the PEG-EuOF nanocrystals have relatively low toxicity, which suggest their safety for in vivo imaging. The studies provide preliminary validation for the use of PEG-EuOF nanocrystals for in vivo bioimaging applications.     

Concordance between whole-slide imaging and light microscopy for routine surgical pathology

The use of high-resolution digital images of histopathology slides as a routine diagnostic tool for surgical pathology was investigated. The study purpose was to determine the diagnostic concordance between pathologic interpretations using whole-slide imaging and standard light microscopy. Two hundred fifty-one consecutive surgical pathology cases (312 parts, 1085 slides) from a single pathology service were included in the study after cases had been signed out and reports generated. A broad array of diagnostic challenges and tissue sources were represented, including 52 neoplastic cases. All cases were digitized at ×20 and presented to 2 pathologists for diagnosis using whole-slide imaging as the sole diagnostic tool. Diagnoses rendered by the whole-slide imaging pathologists were compared with the original light microscopy diagnoses. Overall concordance between whole-slide imaging and light microscopy as determined by a third pathologist and jury panel was 96.5% (95% confidence interval, 94.8%-98.3%). Concordance between whole-slide imaging pathologists was 97.7% (95% confidence interval, 94.7%-99.2%). Five cases were discordant between the whole-slide imaging diagnosis and the original light microscopy diagnosis, of which 2 were clinically significant. Discordance resulted from interpretive criteria or diagnostic error. The whole-slide imaging modality did not contribute to diagnostic differences. Problems encountered by the whole-slide imaging pathologists primarily involved the inability to clearly visualize nuclear detail or microscopic organisms. Technical difficulties associated with image scanning required at least 1 slide be rescanned in 13% of the cases. Technical and operational issues associated with whole-slide imaging scanning devices used in this study were found to be the most significant obstacle to the use of whole-slide imaging in general surgical pathology.     

CT and multimodal imaging findings of primary orbital Ewing's sarcoma involving the middle cranial fossa: a case report

This report details the CT and MR imaging findings of a primary orbital Ewing's sarcoma case involving the middle cranial fossa in a 13-year old boy. CT showed an ill-circumscribed homogeneous soft-tissue density mass with needle-like bone reaction. On MRI, the mass showed homogeneous iso-intensity on T1WI, heterogeneous hyperintensity on T2WI, and marked homogeneous enhancement. Meanwhile, the mass was hyper-intense on DWI, and ADC value was 575×10-6 mm2/s. The mass showed as high rCBV and rCBF, prolonged MTT based on DCSPWI, and wash-out pattern of TIC derived from the DCE-MRI. Our case suggests that functional MRI modalities, including DWI, DSC-PWI or DCE-MR, could provide additional information for differential diagnoses. Both CT and MRI should be performed and comprehensively analyzed for limiting differential diagnoses, determining lesion extension and facilitating operative approach.     

Comparison of magnetic resonance imaging and computed tomography-myelography for quantitative evaluation of lumbar intracanalar cross-section

Purpose

A comparison of MRI and computed tomography-myelography (CTM) for lumbar intracanalar dimensions. To compare the capability and reproducibility of MRI and CTM in measuring the cross-sectional morphology of intracanalar lesions of the lumbar spine.

Materials and Methods

MRI and CTM of lumbar disc levels from 61 subjects with various lumbar spinal diseases were studied. Dural area, dural anteroposterior (AP) diameter, dural right-left diameter, and thickness of the ligamentum flavum were measured by two orthopedic surgeons. Each section was graded by degree of stenosis. Absolute value and intra- and inter-observer correlation coefficients (ICC) of these measurements and the associations between MRI and CTM values were determined.

Results

Except for MRI determination of ligament flavum thickness, CTM and MRI and intra- and ICC suggested sufficient reproducibility. When measurements of dural area, dural AP diameter, and RL diameter were compared, values in CTM were significantly (p = 0.01-0.004) larger than those in MRI (CTM/MRI ratios, 119%, 111%, and 105%, respectively). As spinal stenosis became more severe, discrepancies between CTM and MRI in measurements of the dural sac became larger.

Conclusion

Both CTM and MRI provided reproducible measurements of lumbar intracanalar dimensions. However, flavum thickness may be more accurately measured by CTM. Because the differences in the measurements between CTM and MRI are very slight and there is very little data to suggest that the precise degree of stenosis is related to symptoms or treatment outcome, the usefulness of the CTM over MRI needs to be confirmed in future studies.     

A computed tomography and magnetic resonance imaging study of the variations of the sciatic nerve branches of the pediatric knee: Implications for peripheral nerve blockade

In pediatric patients, peripheral anesthetic blockade of the sciatic nerve is useful for postoperative pain relief after orthopedic procedures of the lower limb. The identification of the sciatic and its branches relative to the surrounding anatomical structures of the knee significantly contribute to the successful nerve blockade. However, reports have demonstrated complications arising from the inadequate and inconsistent understanding of the anatomy of the nerves in the knee region. In addition, the paucity of information regarding the location of the nerves of the knee throughout the pediatric development needs to be addressed in order for peripheral nerve blockades to become more readily used among the pediatric population. This clinical imaging study therefore aimed to document and analyze the relative morphometric relationship of the nerves in the knee region throughout the different stages of pediatric development. The locations of the sciatic, tibial, and common fibular nerves were measured in relation to relevant anatomical structures in 142 pediatric magnetic resonance imaging and computed tomography. A strong correlation was found between age and the distance from the common fibular nerve to the semitendinosus muscle, and thus can be used to predict stature. Significant differences were found between males and females, specifically after puberty, suggesting that sexual dimorphism emerges more distinctively at puberty. In order to predict the location of the nerves at the popliteal fossa, a regression formula using the patient's age and bicondylar width was created. These finding may have significant implications for popliteal approach of the sciatic nerve blockade in pediatric patients. Clin. Anat. 32:836–850, 2019. © 2019 Wiley Periodicals, Inc.