Fast, High-Fidelity Addressed Single-Qubit Gates Using Efficient Composite Pulse Sequences

We use electronic microwave control methods to implement addressed single-qubit gates with high speed and fidelity, for ^{43}Ca^{+} hyperfine "atomic clock" qubits in a cryogenic (100 K) surface trap. For a single qubit, we benchmark an error of 1.5×10^{-6} per Clifford gate (implemented using 600 ns π/2 pulses). For 2 qubits in the same trap zone (ion separation 5  μm), we use a spatial microwave field gradient, combined with an efficient four-pulse scheme, to implement independent addressed gates. Parallel randomized benchmarking on both qubits yields an average error 3.4×10^{-5} per addressed π/2 gate. The scheme scales theoretically to larger numbers of qubits in a single register.

Robust Quantum Memory in a Trapped-Ion Quantum Network Node

We integrate a long-lived memory qubit into a mixed-species trapped-ion quantum network node. Ion-photon entanglement first generated with a network qubit in ^{88}Sr^{+} is transferred to ^{43}Ca^{+} with 0.977(7) fidelity, and mapped to a robust memory qubit. We then entangle the network qubit with a second photon, without affecting the memory qubit. We perform quantum state tomography to show that the fidelity of ion-photon entanglement decays ∼70 times slower on the memory qubit. Dynamical decoupling further extends the storage duration; we measure an ion-photon entanglement fidelity of 0.81(4) after 10 s.

Contrast-Enhanced Ultrasound (CEUS) Identifies Perfusion Differences Between Tibial Fracture Unions and Non-Unions

PURPOSE

 To assess the value of CEUS in the evaluation of tibial fracture perfusion and its ability to differentiate between physiologic and abnormal fracture healing.

MATERIALS AND METHODS

 From 2014 to 2017, 107 patients with tibial fractures or tibial non-unions underwent CEUS examination. CEUS was performed at the regular follow-up examination 26 weeks after osteosynthesis or before non-union surgery. Time-intensity curves (TICs) of the contrast enhancement in the fracture gap were generated, and volume parameters such as wash-in rate (WiR), peak enhancement (PE) and wash-in perfusion index (WiPI) were quantified.

RESULTS

 A total of 34 patients met the inclusion criteria of this study, including 14 consolidated fractures, 12 aseptic non-unions and 8 infected non-unions. WiR, PE and WiPI showed significantly lower values in aseptic non-unions compared to unions (p = 0.009, 0.009, 0.012, resp.). In contrast, infected non-unions showed higher values of WiR, PE and WiPI when compared to unions (p = 0.034, 0.056, 0.029, resp.).

CONCLUSION

 CEUS represents a feasible method in the assessment of tibial fracture perfusion. Perfusion differences between aseptic and infected tibial non-unions as well as healing tibial fractures could be detected. The deviation of physiologic fracture perfusion seems to be associated with disturbed osseous regeneration leading to non-union.

[Certification in cardiology : Contra: The concept should be improved]

Increasing complexity and new highly differentiated therapeutic procedures in cardiology result in a need for additional training beyond cardiology board certification. The German Cardiac Society therefore developed a variety of certifications of educational curricula and definition of specialized centers. Standardization and structuring in education and patient treatment, as defined by certifications may be helpful; however, introduction of certification can have serious consequences for hospital structure, the side effects of which may impair quality of treatment for individual patients. The current article discusses these issues against the background of the following questions: how is quality defined? How do certifications interfere with patient care on a nationwide level, how do they influence responsibilities and teamwork? Are there conflicts of interests by designing certifications and how good are the organizational structures? Finally, suggestions are made on what has to be considered when designing certifications. Certifications should acknowledge all cardiologists, irrespective of their position in the level of care. There should be a coherent unified concept synchronizing all certifications and administration needs to be transparent and well structured.

[Focal lesions in whole-body MRI in multiple myeloma : Quantification of tumor mass and correlation with disease-related parameters and prognosis]

BACKGROUND AND OBJECTIVES

In this study, we evaluated methods of quantification of tumor mass in whole-body MRI (wb-MRI) in multiple myeloma and correlated these with disease-related parameters in serum and bone marrow.

MATERIALS AND METHODS

We retrospectively evaluated wb-MRIs of 52 patients with focal infiltration pattern and a total of 700 focal lesions (subsequently called lesions). We determined the longest diameter (LD), the segmented volume (SV), and the morphology (spherical or non-spherical). We correlated total number/volume of the lesions with clinical parameters and prognosis and furthermore LD with SV. After that we analyzed the agreement of SV and estimated volume (EV) using the volume formula of a sphere based on LD.

RESULTS

Results showed no significant correlations of total number/volume with prognosis or clinical parameters. The latter were situated predominantly in the normal range. Furthermore, 10% of lesions were spherical. SV and LD correlated significantly in single lesions and on patient level. SV was in lesions <6 cm³ systematically larger and in lesions ≥6 cm³ smaller than EV. In 95%, we found in small lesions a deviation of EV versus SV from +0.9 cm³ to -4.6 cm³ and in large lesions from +160 cm³ to -111 cm³ (EV-SV).

CONCLUSIONS

Quantification of tumor mass in the focal infiltration pattern is performed more accurately by volumetry than LD due to the predominant existence of non-spherical lesions. The patient cohort with clinical parameters predominantly in the normal range is distributed to ISS stage I and partly pretreated, a fact that makes interpretation of absent correlations more difficult. Consider also a variation in activitiy of lesions and a diffuse infiltration not detectable by MRI.

CT-Guided Percutaneous Spine Biopsy in Suspected Infection or Malignancy: A Study of 214 Patients

Purpose: To retrospectively determine the effectiveness and accuracy of CT-guided percutaneous biopsy of malignant and inflammatory bone lesions of the spine and to assess the reliability of pre-biopsy CT and MRI. Materials and Methods: 214 patients with lesions of the spine, which were suspicious either for being malignant or inflammatory, underwent CT-guided biopsy for pathological and/or microbiological detection. Biopsy samples were sent for histological examination in 128/214 patients, for microbiological analysis in 17/214 patients and for both analyses in 69/214 patients. Retrospectively, the diagnostic accuracy and sensitivity/specificity of the pre-interventional imaging (CT and MRI) were determined. In addition, the influence of the biopsy on subsequent patient management was assessed. Results: The accuracy was 94.4 % for histopathological analysis and 97.7 % for microbiological analysis. In 25 % of cases the microbiological analysis revealed an underlying pathogen that was not significantly affected by pre-biopsy antibiotic therapy. The sensitivity/specificity of the pre-biopsy cross-sectional imaging concerning suspected malignancy was 69 %/78 %. For suspected infection, the sensitivity/specificity of pre-biopsy imaging was 81 %/44 %. In 52 % of all cases, the biopsy result changed subsequent patient management. Conclusion: Percutaneous CT-guided spine biopsy is a useful and reliable diagnostic procedure to establish a definitive diagnosis but with a relatively low yield of microorganisms in the case of infection. Key Points: • CT-guided spine biopsy is an accurate and reliable procedure in case of infection and tumour.• The results of the CT-guided spine biopsy have a significant influence on the subsequent patient management.• Pathogen recovery-rate in case of infection is moderate but not significantly affected by prebiopsy antibiotic therapy. Citation Format: • Rehm J, Veith S, Akbar M et al. CT-Guided Percutaneous Spine Biopsy in Suspected Infection or Malignancy: A Study of 214 Patients. Fortschr Röntgenstr 2016; 188: 1156 - 1162.

Cloud-Based Evaluation of Anatomical Structure Segmentation and Landmark Detection Algorithms: VISCERAL Anatomy Benchmarks

Variations in the shape and appearance of anatomical structures in medical images are often relevant radiological signs of disease. Automatic tools can help automate parts of this manual process. A cloud-based evaluation framework is presented in this paper including results of benchmarking current state-of-the-art medical imaging algorithms for anatomical structure segmentation and landmark detection: the VISCERAL Anatomy benchmarks. The algorithms are implemented in virtual machines in the cloud where participants can only access the training data and can be run privately by the benchmark administrators to objectively compare their performance in an unseen common test set. Overall, 120 computed tomography and magnetic resonance patient volumes were manually annotated to create a standard Gold Corpus containing a total of 1295 structures and 1760 landmarks. Ten participants contributed with automatic algorithms for the organ segmentation task, and three for the landmark localization task. Different algorithms obtained the best scores in the four available imaging modalities and for subsets of anatomical structures. The annotation framework, resulting data set, evaluation setup, results and performance analysis from the three VISCERAL Anatomy benchmarks are presented in this article. Both the VISCERAL data set and Silver Corpus generated with the fusion of the participant algorithms on a larger set of non-manually-annotated medical images are available to the research community.

Comparison of Modern 3D and 2D MR Imaging Sequences of the Wrist at 3 Tesla

PURPOSE

To compare the image quality of modern 3 D and 2 D sequences for dedicated wrist imaging at 3 Tesla (T) MRI.

MATERIALS AND METHODS

At 3 T MRI, 18 patients (mean age: 36.2 years) with wrist pain and 16 healthy volunteers (mean age: 26.4 years) were examined using 2 D proton density-weighted fat-saturated (PDfs), isotropic 3 D TrueFISP, 3 D MEDIC, and 3 D PDfs SPACE sequences. Image quality was rated on a five-point scale (0 - 4) including overall image quality (OIQ), visibility of important structures (cartilage, ligaments, TFCC) and degree of artifacts. Signal-to-noise ratios (SNR) and contrast-to-noise ratios (CNR) of cartilage/bone/muscle/fluid as well as the mean overall SNR/CNR were calculated using region-of-interest analysis. ANOVA, paired t-, and Wilcoxon-signed-rank tests were applied.

RESULTS

The image quality of all tested sequences was superior to 3 D PDfs SPACE (p < 0.01). 3 D TrueFISP had the highest combined cartilage score (mean: 3.4) and performed better in cartilage comparisons against 3 D PDfs SPACE in both groups and 2 D PDfs in volunteers (p < 0.05). 3 D MEDIC performed better in 7 of 8 comparisons (p < 0.05) regarding ligaments and TFCC. 2 D PDfs provided constantly high scores. The mean overall SNR/CNR for 2 D PDfs, 3 D PDfs SPACE, 3 D TrueFISP, and 3 D MEDIC were 68/65, 32/27, 45/47, and 57/45, respectively. 2 D PDfs performed best in most SNR/CNR comparisons (p < 0.05) and 3 D MEDIC performed best within the 3 D sequences (p < 0.05).

CONCLUSION

Except 3 D PDfs SPACE, all tested 3 D and 2 D sequences provided high image quality. 3 D TrueFISP was best for cartilage imaging, 3 D MEDIC for ligaments and TFCC and 2 D PDfs for general wrist imaging.

KEY POINTS

• 3 D TrueFISP is recommended for cartilage imaging of the wrist at 3 T.• 3 D MEDIC is recommended for ligaments and TFCC.• Robust 2 D PDfs should be used in routine protocols. 3 D sequences may be added depending on the clinical question.• 3 D PDfs SPACE is currently inferior. Citation Format: • Rehnitz C, Klaan B, von Stillfried F et al. Comparison of Modern 3D and 2D MR Imaging Sequences of the Wrist at 3 Tesla. Fortschr Röntgenstr 2016; 188: 753 - 762.

A Generative Probabilistic Model and Discriminative Extensions for Brain Lesion Segmentation--With Application to Tumor and Stroke

We introduce a generative probabilistic model for segmentation of brain lesions in multi-dimensional images that generalizes the EM segmenter, a common approach for modelling brain images using Gaussian mixtures and a probabilistic tissue atlas that employs expectation-maximization (EM), to estimate the label map for a new image. Our model augments the probabilistic atlas of the healthy tissues with a latent atlas of the lesion. We derive an estimation algorithm with closed-form EM update equations. The method extracts a latent atlas prior distribution and the lesion posterior distributions jointly from the image data. It delineates lesion areas individually in each channel, allowing for differences in lesion appearance across modalities, an important feature of many brain tumor imaging sequences. We also propose discriminative model extensions to map the output of the generative model to arbitrary labels with semantic and biological meaning, such as "tumor core" or "fluid-filled structure", but without a one-to-one correspondence to the hypo- or hyper-intense lesion areas identified by the generative model. We test the approach in two image sets: the publicly available BRATS set of glioma patient scans, and multimodal brain images of patients with acute and subacute ischemic stroke. We find the generative model that has been designed for tumor lesions to generalize well to stroke images, and the extended discriminative -discriminative model to be one of the top ranking methods in the BRATS evaluation.

Prevalence of carpal tunnel syndrome and wrist osteoarthritis in long-term paraplegic patients compared with controls

We compared functional and structural changes in the hands, in particular the prevalence of carpal tunnel syndrome, in 56 paraplegic patients who had been wheelchair dependent for over 25 years with a group of able-bodied volunteers (with matching criteria for gender and age). The hands were assessed by clinical examination, electrophysiology, disabilities of the arm shoulder and hand score and magnetic resonance imaging. Hand function was worse and wrist pain was experienced more often in the paraplegic patients, and they also had a significantly higher prevalence of carpal tunnel syndrome both clinically and electrophysiologically. The prevalence of wrist and trapeziometacarpal osteoarthritis was significantly higher in the right hand.

Antihypertensive efficacy of the angiotensin receptor blocker azilsartan medoxomil compared with the angiotensin-converting enzyme inhibitor ramipril

Drug therapy often fails to control hypertension. Azilsartan medoxomil (AZL-M) is a newly developed angiotensin II receptor blocker with high efficacy and good tolerability. This double-blind, controlled, randomised trial compared its antihypertensive efficacy and safety vs the angiotensin-converting enzyme inhibitor ramipril (RAM) in patients with clinic systolic blood pressure (SBP) 150-180 mm Hg. Patients were randomised (n=884) to 20 mg AZL-M or 2.5 mg RAM once daily for 2 weeks, then force-titrated to 40 or 80 mg AZL-M or 10 mg RAM for 22 weeks. The primary endpoint was change in trough, seated, clinic SBP. Mean patient age was 57±11 years, 52.4% were male, 99.5% were Caucasian. Mean baseline BP was 161.1±7.9/94.9±9.0 mm Hg. Clinic SBP decreased by 20.6±0.95 and 21.2±0.95 mm Hg with AZL-M 40 and 80 mg vs12.2±0.95 mm Hg with RAM (P<0.001 for both AZL-M doses). Adverse events leading to discontinuation were less frequent with AZL-M 40 and 80 mg (2.4% and 3.1%, respectively) than with RAM (4.8%). These data demonstrated that treatment of stage 1-2 hypertension with AZL-M was more effective than RAM and better tolerated.

Changing patterns of infant death over the last 100 years: autopsy experience from a specialist children's hospital

OBJECTIVES

Infant mortality has undergone a dramatic reduction in the UK over the past century because of improvements in public health policy and medical advances. Postmortem examinations have been performed at Great Ormond Street Hospital for over 100 years, and analysis of cases across this period has been performed to assess changing patterns of infant deaths undergoing autopsy.

DESIGN

Autopsy reports from 1909 and 2009 were examined. Age, major pathology and cause of death was reviewed from these cases and entered into an anonymized database. A subsequent comparative analysis was performed.

SETTING

All postmortems performed and reported at Great Ormond Street Hospital in 1909 and 2009.

PARTICIPANTS

Infant deaths, aged 0-365 days, were identified and subsequently analysed for the two years.

MAIN OUTCOME MEASURES

Comparative proportional analysis of postmortem findings from the two time periods.

RESULTS

Three-hundred and fifty-seven and 347 autopsy reports were identified from 1909 and 2009 including 178 and 128 infant deaths, respectively. The commonest cause of death in 1909 was infection (74%) compared to 20% of deaths in 2009. The most frequent final 'diagnosis' in 2009 was 'unexplained sudden unexpected infant death (SUDI)', despite a full postmortem including ancillary investigations. In contrast, there were no such cases recorded in 1909, but there were frequent deaths due to gastroenteritis and malnutrition together accounting for 16% of cases, compared to one case of gastroenteritis in 2009. Fifteen percent of 1909 cases had infections which are almost never fatal with appropriate treatment in 2009, including tuberculosis, diphtheria and syphilis. Congenital anomalies were detected with similar frequencies at both time points, (21% and 19% in 1909 and 2009, respectively).

CONCLUSION

In the UK, significant changes in patterns of pathology have occurred in paediatric autopsy cases performed at a single specialist centre. Fatal infections and malnutrition (both poverty-related) have reduced yet the incidence of congenital anomalies has remained similar.

Histological examination in sudden unexpected death in infancy: evidence base for histological sampling

AIM

Pathologists currently follow the 'Kennedy guidelines' when performing autopsies for sudden unexpected death in infancy (SUDI); these include extensive histological sampling. This study establishes the frequency with which histological examination of visceral organs determines cause of death and examines associations between clinical, macroscopic and microscopic findings.

METHODS

Retrospective review of 546 SUDI autopsies performed for a 10-year period (1996-2005) at a single centre. The proportion of cases in which non-neuropathological histological examination directly determined the cause of death was identified, and clinical, macroscopic and histological findings at autopsy were compared.

RESULTS

Of 510 SUDIs included, 166 cases were explained SUDI, and of these, 54% (89/166) were identified solely on microscopic examination, based on histology of the lungs in 71 (43%), heart in 13 (8%), liver in 4 (2%) and kidneys in 1 (<1%). The proportions of macroscopically normal organs with significant histological findings were 26% lungs, 2% heart and 1% each of liver and kidneys, but none of spleen, thymus, pancreas or adrenals. Macroscopically abnormal organs were more likely to yield significant histological features. Symptoms preceding death were more common in cases with significant histological findings in lungs, heart, liver and adrenals.

CONCLUSION

A non-neuropathological cause of death in explained SUDI can be established from histological examination of lungs, heart, liver and kidneys. Significant histological abnormalities may be detected in selected organs with macroscopically normal appearances. Routine histological sampling of other organs in the absence of specific clinical history or macroscopic abnormalities has a low yield for establishing cause of death.

Tandem mass spectrometry findings at autopsy for detection of metabolic disease in infant deaths: postmortem changes and confounding factors

AIM

Tandem mass spectrometry (MS/MS) is a recommended investigation for sudden unexpected death in infancy (SUDI), but there are limited data regarding yield and potential influencing factors. This study investigates postmortem acylcarnitine profiles in a large cohort of infant deaths from a single centre, including those with metabolic disease.

METHODS

Acylcarnitine results obtained by MS/MS from routine blood/bile spot samples during the standard autopsy investigation were identified from infant deaths over a 14-year period. Results were categorised as normal or abnormal according to the clinical report by a specialist paediatric biochemist. Possible interdependent variables were assessed, multiple linear regression models were constructed and residual comparison was undertaken.

RESULTS

397 blood and 268 bile MS/MS results were identified from infant cases, including 255 matched blood-bile pairs. There was significant association between blood acylcarnitine findings and postmortem interval (PMI), body mass index and liver weight. A probable cause of death was identified in 40% of sudden death cases, including 18 (2%) with a definite or highly likely cause of death as underlying metabolic disease; this represented 12 (12%) unexpected deaths in the first week of life and six (<1%) aged 7-365 days. Fatty acid oxidation disorders identified included very long chain acyl-CoA dehydrogenase deficiency, medium chain acyl-CoA dehydrogenase deficiency and carnitine transporter defects.

CONCLUSION

Postmortem blood and bile acylcarnitine profiles are influenced by several variables, and PMI can influence MS/MS acylcarnitine results. Metabolic disease may present as SUDI and may be identified from postmortem samples.

Virological investigations in sudden unexpected deaths in infancy (SUDI)

Previous studies have implicated viral infections in the pathogenesis of sudden unexpected death in infancy (SUDI), and routine virological investigations are recommended by current SUDI autopsy protocols. The aim of this study is to determine the role of post-mortem virology in establishing a cause of death. A retrospective review of 546 SUDI autopsies was carried out as part of a larger series of >1,500 consecutive paediatric autopsies performed over a 10-year period, 1996-2005, in a single specialist centre. Virological tests were performed as part of the post-mortem examination in 490 (90%) of the 546 SUDI autopsies, comprising 4,639 individual virological tests, of which 79% were performed on lung tissue samples. Diagnostic methods included immunofluorescence assays (using a routine respiratory virus panel; 98% of cases), cell culture (61%), rapid culture techniques such as the DEAFF test for CMV (55%), PCR (13%), electron microscopy (10%), and others. Virus was identified in only 18 cases (4%), viz. five cases of enterovirus, four of RSV, three of HSV and CMV, and one each of adenovirus, influenza virus and HIV. In seven of the 18 cases the death was classified as due to viral infection, whilst of the remaining 11 cases, death was due to bacterial infection in five, a non-infective cause in one and unexplained in five. Virus was identified in 33% of deaths due to probable viral infections, but also in 6% of SUDI due to bacterial infections, and in 2% of SUDI due to known non-infective causes and unexplained SUDI. When predominantly using immunofluorescence, virus is identified in only a small proportion of SUDI autopsies, resulting in a contribution to the final cause of death in <2% of SUDI post-mortem examinations. Routine post-mortem virological analysis by means of an immunofluorescence respiratory virus panel appears to be of limited benefit in SUDI for the purposes of determining cause of death. Application of a broader panel using more sensitive detection techniques may reveal more viruses, although their contribution to the final cause of death requires further exploration.

Prospective parental consent for autopsy research following sudden unexpected childhood deaths: a successful model

BACKGROUND

Organ retention issues, recent changes in the Coroners' (Amendment) Rules 2005 and the Human Tissue Act have resulted in pessimism regarding prospective consent for paediatric autopsy research in the UK.

OBJECTIVES

To examine the feasibility and acceptability of a prospective telephone consenting model for post-mortem magnetic resonance (MR) imaging research in HM Coroners' cases.

DESIGN

Following each autopsy referral from the HM Coroner, permission to contact the family for research was requested. A family liaison sister, with experience in dealing with bereaved families, then contacted the parents by telephone, explained the study and obtained oral, and then written consent for post-mortem imaging.

SETTING

London and an area south of London.

RESULTS

Of 76 eligible HM Coroners' cases referred during the study period, permission to contact parents (provided by the HM Coroners' Office) was obtained for only 32 cases (42%). The research sister contacted 32 parents during the study period of whom 31 (96.8%) gave oral research consent. "Helping other parents in the future" and "the importance of post-mortem research" were the main reasons for parents wanting to participate in research.

CONCLUSIONS

Prospective consenting for HM Coroners' cases for research is feasible in children, and can be done ethically by parental consenting via telephone contact before autopsy by appropriately trained staff. However, close co-ordination between mortuary staff, HM Coroners, research staff and medical staff is required. This model may be useful in performing post-mortem research in HM Coroners' cases and in developing paediatric tissue and brain banks in the UK.

The role of post-mortem investigations in determining the cause of sudden unexpected death in infancy

INTRODUCTION

Several autopsy protocols have been suggested for investigating sudden unexpected deaths in infancy (SUDI). The aim of this study is to provide data on the utility of such post-mortem investigations from a large paediatric autopsy series to inform future policy.

METHODS

Retrospective analysis of >1500 consecutive post-mortem examinations carried out by specialist paediatric pathologists at a single centre during a 10-year period according to a common autopsy protocol that included the use of detailed ancillary investigations. SUDI was defined as the sudden unexpected death of an infant aged from 7 to 365 days. All data capture and cause of death classification were carried out according to defined criteria.

RESULTS

Of 1516 paediatric post-mortem examinations, 546 presented as SUDI. In 202 infants (37%), death was explained by the autopsy findings. The other 344 cases (63%) remained unexplained. Of the explained deaths, over half (58%) were infective, most commonly due to pneumonia (22%). The component of the post-mortem examination that primarily determined the final cause of death was histological examination in 92 infants (46%), macroscopic examination in 61 (30%), microbiological investigations in 38 (19%) and clinical history in 10 (5%).

CONCLUSION

This constitutes the largest single-institution autopsy study of SUDI. Ten years on from the Confidential Enquiry into Stillbirths and Deaths in Infancy (CESDI) SUDI studies, the ascertainment of a cause of death at autopsy has improved. However, with almost two thirds of SUDI remaining unexplained, alternative and/or additional diagnostic techniques are required to improve detection rates of identifiable causes of death at autopsy.

Clinicopathological features of paediatric deaths due to myocarditis: an autopsy series

INTRODUCTION

Myocarditis is a recognised cause of cardiac failure in childhood but the frequency of myocarditis as a cause of sudden unexpected death across the paediatric age range is uncertain.

METHODS

A structured review of the results of all autopsies carried out in a single paediatric centre over a 10-year period, including the results of all investigations performed as part of the centre's policy for the post-mortem investigation of paediatric deaths.

RESULTS

During the study period there were 1516 autopsies of children aged 0-18 years. Histologically proven myocarditis was present in 28 cases (1.8%, age range 10 days to 16 years, median age 10 months), of which 16 (57%) presented as sudden death. More than half of all cases (54%) occurred in infants less than 1 year of age, accounting for 2% of infant deaths referred for autopsy, compared with around 5% of childhood deaths over the age of 5 years. In almost 40% of cases there were no macroscopic cardiac abnormalities, the diagnosis being entirely dependent on routine histological examination of the heart, and post-mortem heart weight was normal in the majority of cases. Virus was detected in nine (36%) of the 25 cases in whom virological analyses were performed. The histological features were similar in all cases, with an interstitial inflammatory cell infiltrate, predominantly lymphocytic, with focal myocyte necrosis and interstitial oedema.

CONCLUSIONS

Myocarditis is a rare cause of death in infancy and childhood, and the majority of cases present as sudden unexpected deaths, which require routine histological sampling of the heart for its detection.

Infection and sudden unexpected death in infancy: a systematic retrospective case review

BACKGROUND

The cause and mechanism of most cases of sudden unexpected death in infancy (SUDI) remain unknown, despite specialist autopsy examination. We reviewed autopsy results to determine whether infection was a cause of SUDI.

METHODS

We did a systematic retrospective case review of autopsies, done at one specialist centre between 1996 and 2005, of 546 infants (aged 7-365 days) who died suddenly and unexpectedly. Cases of SUDI were categorised as unexplained, explained with histological evidence of bacterial infection, or explained by non-infective causes. Microbial isolates gathered at autopsy were classified as non-pathogens, group 1 pathogens (organisms usually associated with an identifiable focus of infection), or group 2 pathogens (organisms known to cause septicaemia without an obvious focus of infection).

FINDINGS

Of 546 SUDI cases, 39 autopsies were excluded because of viral or pneumocystis infection or secondary bacterial infection after initial collapse and resuscitation. Bacteriological sampling was done in 470 (93%) of the remaining 507 autopsies. 2079 bacteriological samples were taken, of which 571 (27%) were sterile. Positive cultures yielded 2871 separate isolates, 484 (32%) of which showed pure growth and 1024 (68%) mixed growth. Significantly more isolates from infants whose deaths were explained by bacterial infection (78/322, 24%) and from those whose death was unexplained (440/2306, 19%) contained group 2 pathogens than did those from infants whose death was explained by a non-infective cause (27/243, 11%; difference 13.1%, 95% CI 6.9-19.2, p<0.0001 vs bacterial infection; and 8.0%, 3.2-11.8, p=0.001 vs unexplained). Significantly more cultures from infants whose deaths were unexplained contained Staphylococcus aureus (262/1628, 16%) or Escherichia coli (93/1628; 6%) than did those from infants whose deaths were of non-infective cause (S aureus: 19/211, 9%; difference 7.1%, 95% CI 2.2-10.8, p=0.005; E coli: 3/211, 1%, difference 4.3%, 1.5-5.9, p=0.003).

INTERPRETATION

Although many post-mortem bacteriological cultures in SUDI yield organisms, most seem to be unrelated to the cause of death. The high rate of detection of group 2 pathogens, particularly S aureus and E coli, in otherwise unexplained cases of SUDI suggests that these bacteria could be associated with this condition.

Pharmacokinetic analysis of malignant pleural mesothelioma-initial results of tumor microcirculation and its correlation to microvessel density (CD-34)

RATIONALE AND OBJECTIVES

Malignant mesothelioma (MM) of the pleura is an aggressive and often fatal neoplasm. Because MM frequently demonstrates marked angiogenesis, it may be responsive to antiangiogenic therapy, but effective methods for selecting and monitoring of patients are further needed. We employed dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and quantitative immunohistochemistry (IHC) to characterize the microvascularity of MM using both a physiologic and ultrastructural method.

MATERIALS AND METHODS

Nineteen patients diagnosed with MM were enrolled and DCE-MRI was performed before antiangiogenic treatment. For each patient, tumor regions were characterized by their DCE-MRI-derived pharmacokinetic parameters (Amp, k(ep), k(el)), which were also compared to those of normal tissue (aorta, liver, spleen, and muscle). In addition, quantitative IHC of representative samples was performed with CD-34 staining to compare the calculated microvessel density (MVD) results with DCE-MRI results.

RESULTS

MM demonstrated markedly abnormal pharmacokinetic properties compared with normal tissues. Among the parameters tested, Amp was significantly different in MM (P < or = .001) compared to normal organs. Despite the observation that the MVD of mesotheliomas in this series was high compared to other tumors, DCE-MRI pharmacokinetic parameters had a moderately positive correlation with MVD (r = 0.5).

CONCLUSIONS

DCE-MRI and IHC can be used in patients with MM to visualize tumor microvascularity and to characterize tumor heterogeneity. DCE-MRI and IHC results positively correlated, though moderately, but these two methods present as essential tumor biomarkers. This multimodal characterization may be useful in selecting possible tumor subtypes that would benefit from antiangiogenic therapy.

Treatment of microalbuminuria in hypertensive subjects with elevated cardiovascular risk: Results of the IMPROVE trial

Microalbuminuria independently predicts increased cardiovascular risk in hypertensive patients, especially in those with concomitant diabetes or established cardiovascular disease. Drugs that target the renin-angiotensin-aldosterone system reduce microalbuminuria regardless of diabetic status. The Irbesartan in the Management of PROteinuric patients at high risk for Vascular Events was a multicenter, randomized, double-blind, placebo-controlled paralleled group study in which hypertensive patients with microalbuminuria and increased cardiovascular risk were randomized to 20 weeks treatment with ramipril plus irbesartan or to ramipril plus placebo. Patients discontinued or tapered previous antihypertensive therapy during a 14-day placebo lead-in period. Change in albumin excretion rate from baseline to week 20 was the primary end point. Adjusted week 20 baseline geometric ratios for ramipril plus irbesartan and ramipril plus placebo were not significantly different. Although differences in blood pressure reductions were observed between the two treatments, these changes did not affect microalbuminuria. More patients on dual therapy achieved target blood pressure goals at week 20 than with monotherapy. The incidence of adverse effects and treatment-related adverse effects was similar in both groups. Our results suggest that patients with cardiovascular risk and relatively low albumin excretion rates in early-stage disease may only require monotherapy with renin-angiotensin-aldosterone blocking agents.

Challenges to implementation of the new Coroners' (Amendment) Rules 2005: experience from a tertiary paediatric pathology centre

In the UK sudden unexpected childhood deaths are referred to Her Majesty's Coroner (HMC) for postmortem examination during which small tissue samples are obtained for diagnostic purposes. Recent changes to regulate tissue use include the Coroners' (Amendment) Rules 2005. We audited the impact of these at a specialist paediatric centre. A retrospective audit of HMC tissue forms for autopsies was performed between 1 June 2005 - 31 May 2006, with regard to the options provided to, and chosen by, parents. Of 213 coronial autopsies, 178 were non-forensic. Tissue forms were submitted pre-autopsy in 25 (14%). An additional 47 were received after sending follow-up letters for a total of 72/178 (40%). Forms varied between coroners, but most failed to distinguish between blocks, slides, and other tissue samples and 6/40 (15%) forms did not specifically allow an option for research consent. Forty-three (60%) parents opted for retention, with 34 (79%) also consenting to research. Only six (8%) requested return of tissue. A simple, unified tissue disposal form and information sheet for all HMC districts, which includes appropriate options, would ensure that parents' wishes are met, to achieve best practice, maximise sample availability for positive societal outcomes such as teaching and research, and to comply with new regulations.

Funktionelle Bildgebung bei Hirntumoren (Perfusion, DTI, MR-Spektroskopie)

This contribution considers the possibilities involved with using functional methods in magnetic resonance imaging (MRI) diagnostics for brain tumors. Of the functional methods available, we discuss perfusion MRI (PWI), diffusion MRI (DWI and DTI) and MR spectroscopy (H-MRS). In cases of brain tumor, PWI aids in grading and better differentiation in diagnostics as well as for pre-therapeutic planning. In addition, the course of treatment, both after chemo- as well as radiotherapy in combination with surgical treatment, can be optimized. PWI allows better estimates of biological activity and aggressiveness in low grade brain tumors, and in the case of WHO grade II astrocytoma showing anaplasically transformed tumor areas, allows more rapid visu-alization and a better prediction of the course of the disease than conventional MRI diagnostics. Diffusion MRI, due to the directional dependence of the diffusion, can illustrate the course and direction of the nerve fibers, as well as reconstructing the nerve tracts in the cerebrum, pons and cerebellum 3-dimensionally. Diffusion imaging can be used for describing brain tumors, for evaluating contralateral involvement and the course of the nerve fibers near the tumor. Due to its operator dependence, DTI based fiber tracking for defining risk structures is controversial. DWI can also not differentiate accurately between cystic and necrotic brain tumors, or between metastases and brain abscesses. H-MRS provides information on cell membrane metabolism, neuronal integrity and the function of neuronal structures, energy metabolism and the formation of tumors and brain tissue necroses. Diagnostic problems such as the differentiation between neoplastic and non-neoplastic lesions, grading cerebral glioma and distinguishing between primary brain tumors and metastases can be resolved. An additional contribution will discuss the control of the course of glial tumors after radiotherapy.

Ultrastructural features of gaucher disease treated with enzyme replacement therapy presenting as mesenteric mass lesions

The classical ultrastructural features of Gaucher disease include large numbers of intracytoplasmic, membrane-bound lysosomal inclusions containing characteristic tubular structures on an electron-lucent background, representing the periodic acid schiff (PAS)-positive Gaucher cells identifiable on light microscopy. Following enzyme replacement therapy (ERT), many of the manifestations of the condition are ameliorated, but persistent mesenteric lymphadenopathy has been reported, the ultrastructural features of which previously have not been described. Two children, aged 4 and 8 years old, respectively, both presented with persistent abdominal lymphadenopathy whilst receiving ERT for Gaucher disease. Needle core biopsies were carried out, that demonstrated collections of macrophages and only scattered storage-type cells on light microscopy. PAS staining was negative in one case and only focally positive in the other Electron microscopic examination, however, confirmed the cells represented macrophages, the cytoplasm of which contained scattered abnormal inclusions containing occasional twisted tubular structures of the type reported in classic Gaucher disease. ERT in Gaucher disease appears to reduce accumulation of the metabolic products at many sites. But for uncertain reasons, abdominal lymphadenopathy may occur containing macrophages that do not form granulomas or classic Gaucher cells on light microscopy. These probably represent incomplete clearance, incomplete/partial enzyme replacement, or possibly an unusual response to a relatively small amount of storage material.

Diagnostic performance of spectroscopic and perfusion MRI for distinction of brain tumors

OBJECTIVE

To assess the value of spectroscopic and perfusion MRI for glioma grading and for distinguishing glioblastomas from metastases and from CNS lymphomas.

METHODS

The authors examined 79 consecutive patients with first detection of a brain neoplasm on nonenhanced CT scans and no therapy prior to evaluation. Spectroscopic MRI; arterial spin-labeling MRI for measuring cerebral blood flow (CBF); first-pass dynamic, susceptibility-weighted, contrast-enhanced MRI for measuring cerebral blood volume; and T1-weighted dynamic contrast-enhanced MRI were performed. Receiver operating characteristic analysis was performed, and optimum thresholds for tumor classification and glioma grading were determined.

RESULTS

Perfusion MRI had a higher diagnostic performance than spectroscopic MRI. Because of a significantly higher tumor blood flow in glioblastomas compared with CNS lymphomas, a threshold value of 1.2 for CBF provided sensitivity of 97%, specificity of 80%, positive predictive value (PPV) of 94%, and negative predictive value (NPV) of 89%. Because CBF was significantly higher in peritumoral nonenhancing T2-hyperintense regions of glioblastomas compared with metastases, a threshold value of 0.5 for CBF provided sensitivity, specificity, PPV, and NPV of 100%, 71%, 94%, and 100%. Glioblastomas had the highest tumor blood flow values among all other glioma grades. For discrimination of glioblastomas from grade 3 gliomas, sensitivity was 97%, specificity was 50%, PPV was 84%, and NPV was 86% (CBF threshold value of 1.4), and for discrimination of glioblastomas from grade 2 gliomas, sensitivity was 94%, specificity was 78%, PPV was 94%, and NPV was 78% (CBF threshold value of 1.6).

CONCLUSION

Perfusion MRI is predictive in distinguishing glioblastomas from metastases, CNS lymphomas and other gliomas vs MRI and magnetic resonance spectroscopy.