Sociodemographic disparities and potential biases in persistent pain estimates: Findings from 5 waves of the Irish Longitudinal Study on Ageing (TILDA)

BACKGROUND

Pain is a prevalent, debilitating condition among older adults. Much evidence on this topic comes from cohort studies, which may be affected by attrition and measurement bias. Little is known about the impact of these biases on pain estimates for European older adults. Additionally, there is a lack of longitudinal research on pain and sociodemographic disparities in Irish older adults.

METHODS

We analysed data from 8171 participants (aged ≥50 at baseline) across five waves of the Irish Longitudinal Study on Ageing. Longitudinal pain severity and sociodemographic disparities in pain were explored visually and using a latent growth curve model. Using multivariate logistic regression, we examined bias due to attrition at later waves associated with reported pain at Wave 1. Measurement biases due to reporting heterogeneity were assessed by investigating associations between sociodemographic factors and pain-related disability for given pain levels.

RESULTS

Wave 1 severe pain was associated with increased odds of attrition due to death by Wave 5 (AOR: 1.63, 95% CI: 1.20, 2.19). Not having private health insurance was associated with increased odds of pain-related disability at Wave 1, controlling for pain severity (AOR: 1.37, 95% CI: 1.15, 1.64). These results suggested mortality bias and reporting heterogeneity measurement bias, respectively. Sex, education level, and private health insurance status disparities in pain were observed longitudinally.

CONCLUSIONS

Mortality bias and reporting heterogeneity measurement bias must be accounted for to improve older adult pain estimates. There is a need for policymakers to address sociodemographic disparities in older adult pain levels.

SIGNIFICANCE

This study highlights a need to address bias in the estimation of pain in observational studies of older adults. Understanding the sources and extent of these biases is important so that health practices and policies to address pain disparities can be guided by accurate estimates. Women, those with lower educational attainment, and those without private health insurance were found to have the highest pain burden longitudinally, suggesting a need for targeted interventions for these groups in Ireland and internationally.

Education as Risk Factor of Mild Cognitive Impairment: The Link to the Gut Microbiome

BACKGROUND

With differences apparent in the gut microbiome in mild cognitive impairment (MCI) and dementia, and risk factors of dementia linked to alterations of the gut microbiome, the question remains if gut microbiome characteristics may mediate associations of education with MCI.

OBJECTIVES

We sought to examine potential mediation of the association of education and MCI by gut microbiome diversity or composition.

DESIGN

Cross-sectional study.

SETTING

Luxembourg, the Greater Region (surrounding areas in Belgium, France, Germany).

PARTICIPANTS

Control participants of the Luxembourg Parkinson's Study.

MEASUREMENTS

Gut microbiome composition, ascertained with 16S rRNA gene amplicon sequencing. Differential abundance, assessed across education groups (0-10, 11-16, 16+ years of education). Alpha diversity (Chao1, Shannon and inverse Simpson indices). Mediation analysis with effect decomposition was conducted with education as exposure, MCI as outcome and gut microbiome metrics as mediators.

RESULTS

After exclusion of participants below 50, or with missing data, n=258 participants (n=58 MCI) were included (M [SD] Age=64.6 [8.3] years). Higher education (16+ years) was associated with MCI (Odds ratio natural direct effect=0.35 [95% CI 0.15-0.81]. Streptococcus and Lachnospiraceae-UCG-001 genera were more abundant in higher education.

CONCLUSIONS

Education is associated with gut microbiome composition and MCI risk without clear evidence for mediation. However, our results suggest signatures of the gut microbiome that have been identified previously in AD and MCI to be reflected in lower education and suggest education as important covariate in microbiome studies.

Cancer-associated mesothelial cells are regulated by the anti-Müllerian hormone axis

Cancer-associated mesothelial cells (CAMCs) in the tumor microenvironment are thought to promote growth and immune evasion. We find that, in mouse and human ovarian tumors, cancer cells express anti-Müllerian hormone (AMH) while CAMCs express its receptor AMHR2, suggesting a paracrine axis. Factors secreted by cancer cells induce AMHR2 expression during their reprogramming into CAMCs in mouse and human in vitro models. Overexpression of AMHR2 in the Met5a mesothelial cell line is sufficient to induce expression of immunosuppressive cytokines and growth factors that stimulate ovarian cancer cell growth in an AMH-dependent way. Finally, syngeneic cancer cells implanted in transgenic mice with Amhr2-/- CAMCs grow significantly slower than in wild-type hosts. The cytokine profile of Amhr2-/- tumor-bearing mice is altered and their tumors express less immune checkpoint markers programmed-cell-death 1 (PD1) and cytotoxic T lymphocyte-associated protein 4 (CTLA4). Taken together, these data suggest that the AMH/AMHR2 axis plays a critical role in regulating the pro-tumoral function of CAMCs in ovarian cancer.

Alterations of oral microbiota and impact on the gut microbiome in type 1 diabetes mellitus revealed by integrated multi-omic analyses

BACKGROUND

Alterations to the gut microbiome have been linked to multiple chronic diseases. However, the drivers of such changes remain largely unknown. The oral cavity acts as a major route of exposure to exogenous factors including pathogens, and processes therein may affect the communities in the subsequent compartments of the gastrointestinal tract. Here, we perform strain-resolved, integrated meta-genomic, transcriptomic, and proteomic analyses of paired saliva and stool samples collected from 35 individuals from eight families with multiple cases of type 1 diabetes mellitus (T1DM).

RESULTS

We identified distinct oral microbiota mostly reflecting competition between streptococcal species. More specifically, we found a decreased abundance of the commensal Streptococcus salivarius in the oral cavity of T1DM individuals, which is linked to its apparent competition with the pathobiont Streptococcus mutans. The decrease in S. salivarius in the oral cavity was also associated with its decrease in the gut as well as higher abundances in facultative anaerobes including Enterobacteria. In addition, we found evidence of gut inflammation in T1DM as reflected in the expression profiles of the Enterobacteria as well as in the human gut proteome. Finally, we were able to follow transmitted strain-variants from the oral cavity to the gut at the individual omic levels, highlighting not only the transfer, but also the activity of the transmitted taxa along the gastrointestinal tract.

CONCLUSIONS

Alterations of the oral microbiome in the context of T1DM impact the microbial communities in the lower gut, in particular through the reduction of "mouth-to-gut" transfer of Streptococcus salivarius. Our results indicate that the observed oral-cavity-driven gut microbiome changes may contribute towards the inflammatory processes involved in T1DM. Through the integration of multi-omic analyses, we resolve strain-variant "mouth-to-gut" transfer in a disease context. Video Abstract.

Age at onset as stratifier in idiopathic Parkinson’s disease – effect of ageing and polygenic risk score on clinical phenotypes

Several phenotypic differences observed in Parkinson’s disease (PD) patients have been linked to age at onset (AAO). We endeavoured to find out whether these differences are due to the ageing process itself by using a combined dataset of idiopathic PD (n = 430) and healthy controls (HC; n = 556) excluding carriers of known PD-linked genetic mutations in both groups. We found several significant effects of AAO on motor and non-motor symptoms in PD, but when comparing the effects of age on these symptoms with HC (using age at assessment, AAA), only positive associations of AAA with burden of motor symptoms and cognitive impairment were significantly different between PD vs HC. Furthermore, we explored a potential effect of polygenic risk score (PRS) on clinical phenotype and identified a significant inverse correlation of AAO and PRS in PD. No significant association between PRS and severity of clinical symptoms was found. We conclude that the observed non-motor phenotypic differences in PD based on AAO are largely driven by the ageing process itself and not by a specific profile of neurodegeneration linked to AAO in the idiopathic PD patients.

Place of death in Europe: trends and associations in a 30-country panel (2005-2017)

Background

End-of-life care attracts major policy interest. Place of death is an important metric of individual experience and health system performance. Most people prefer to die at home, but hospital is the most common place of death in high-income countries. Little is known about international trends in place of death over time.

Methods

We aimed to collate population-level data on place of death in Europe for the years 2005-2017, and to evaluate association with national characteristics and policy choices. We sought outcome data from the 32 European Economic Area countries. We identified national economic, societal, demographic and health system predictors from Eurostat, OECD and the WHO. We analysed these cross-national panel data using linear regression with panel-corrected standard errors.

Results

Our analytic dataset included 30 countries accounting for over 95% of Europe's population and economic activity. Average national proportion of deaths occurring in hospital in the study period ranged from 26% to 68%, with a median of 52%. Trends vary markedly by region and wealth, with low and decreasing hospital deaths in the North-West, and high and increasing prevalence in the South and East. Controlling for demographic and economic factors, strong palliative care provision and generous government finance of long-term care were associated with fewer hospital deaths.

Conclusions

We found modifiable policy choices associated with hospital mortality, as well as wider structural economic and societal factors. Policymakers can act to curb worrisome trends in-hospital mortality. Data on places of death outside hospital can improve future research, policy and practice.

Key messages

Cross-national longitudinal analysis. Trends of hospital deaths in Europe, association between hospital mortality rate, palliative care and other healthcare factors.

Health and social care near the end of life: Can policies reduce costs and improve outcomes?

Background

A key concern related to population ageing is how it will impact on health and social care use and expenditure trends. The belief that older people are more costly for health and social care systems than younger people is pervasive, and so the logic goes that having a larger share of the population at older ages may unsustainably accelerate growth in public health spending. In reality, the evidence suggests that the effects of ageing on health care costs will be modest and growth will be slow, but there will naturally be some additional care needs. Health and social care costs can nevertheless be particularly high for people near the end of life. In fact, the costs associated with end of life care largely explain why health and social care expenditures per person, on average, are higher for older people than for younger people, since most people die at older ages.

Methods

Literature review of patterns of service use and costs of care at the end of life; how needs for end of life care are likely to change with population ageing; and effects of end of life care interventions on patterns and costs of care.

Results

The evidence suggests that costs near the end of life vary greatly, and high overall costs are driven by service use by a small proportion of decedents.

Conclusions

Although the numbers of people with needs for palliative and end of life care will rise with population ageing, a review of the literature indicates that it is possible to reduce use of services and costs, and to improve patient experiences with well-designed palliative and end of life care interventions.

Immunisation Status of Children with Cerebral Palsy in Rural Bangladesh: Results from the Bangladesh Cerebral Palsy Register (BCPR)

BACKGROUND

Cerebral palsy (CP) is the most common cause of physical disability in childhood, with an estimated 17 million cases worldwide. There is limited data concerning the general health of this population and the immunisation status of children with CP is largely unknown.

OBJECTIVE

We aimed to assess the immunisation status of children with CP in rural Bangladesh and determine the predictors of non-immunisation.

METHODS

This study is part of the Bangladesh CP Register (BCPR) study; a population based CP register commenced in January 2015 in the Shahjadpur sub-district of Bangladesh. As part of BCPR registration, all children with CP in the catchment area were assessed by a paediatrician and their clinical and immunisation history were collected.

RESULTS

Between January and December 2015, 615 children with CP were registered on the BCPR. The median age of the children was 7.5 years, and 38.5% were female. 91.7% of those children had a BCG vaccine scar (as an objective marker for immunisation at birth). However, only 43.2% reported to have received the rubella vaccine during the 2014 national rubella immunisation campaign. Timing of CP diagnosis was found to be an independent predictor for immunisation uptake; those diagnosed before the age of 3 were more likely to have received the rubella vaccine (95% confidence interval [CI] 1.6 - 4.3, odds ratio [OR] 2.6, p <0.0001).

CONCLUSIONS

To the best of our knowledge, this is the first paper to use a formal CP register to examine the relationship between CP and immunisation status in a low or middle income country like Bangladesh. Our data suggest that more than half of children with CP in rural Bangladesh did not receive immunisation during a recent national campaign.

Academic neurosurgery in the UK: present and future directions

Academic neurosurgery encompasses basic science and clinical research efforts to better understand and treat diseases of relevance to neurosurgical practice, with the overall aim of improving treatment and outcome for patients. In this article, we provide an overview of the current and future directions of British academic neurosurgery. Training pathways are considered together with personal accounts of experiences of structured integrated clinical academic training and unstructured academic training. Life as an academic consultant is also described. Funding is explored, for the specialty as a whole and at the individual level. UK academic neurosurgical organisations are highlighted. Finally, the UK's international standing is considered.

Creating a Synthetic Clinical Trial: Comparative Effectiveness Analyses Using an Electronic Medical Record

PURPOSE

Electronic medical records (EMRs) are a vast resource of potentially mineable data that can be used to complement and extend clinical trials. Extracting and analyzing EMR data are impeded by technical complexities associated with large, multiformat databases. We sought to develop and validate a framework that would overcome the difficulties associated with EMR data and create a simple, portable, and expandable system to better use this resource.

MATERIALS AND METHODS

An Internet-accessible program was developed in Python that applied user-defined criteria to identify and extract patient data from Memorial Sloan Kettering databases. A Worker Application composed of individual modules was developed to identify each patient's functional status, smoking status, and treatment classification. The validity of this approach was tested by identifying, extracting, and analyzing data from a patient cohort that paralleled a practice-changing, prospective, randomized phase III clinical trial performed at a different institution. We called this a synthetic clinical trial.

RESULTS

Our synthetic clinical trial identified and extracted data on a cohort of 281 patients with lung cancer who matched inclusion criteria and received their first treatment between October 2003 and July 2010. The data extraction modules were precise and accurate, with F-measures greater than 0.98. Results were similar in directionality and magnitude to the chosen comparator clinical trial.

CONCLUSION

Our framework offers an accurate and user-friendly interface for identifying and extracting EMR data that can be used to create synthetic clinical trials. Additional studies are needed to validate this approach in other patient cohorts, replicate our findings, and leverage this methodology to improve patient care and accelerate drug development.

Passive eye movements induced by electromagnetic force (EMF) in rats

Accurate information on eye position in the orbit is available from visual feedback, efference copy of the oculomotor commands and proprioceptive signals from the extraocular muscles (EOM). Whereas visual feedback and oculomotor commands have been extensively studied, central processing of EOM proprioceptive signals remains to be elucidated. A challenge to the field is to develop an approach to induce passive eye movements without physically contacting the eyes. A novel method was developed to generate passive eye movements in rats. A small rare-earth magnet disk (0.7 mm diameter, 0.5 mm thickness) was attached to the surface of a rat's eyeball. A metal rod (5 mm diameter) wrapped with an electromagnetic (EM) coil was placed near the magnet (8-15 mm). By passing currents to the EM coil, electromagnetic force (EMF) was generated and acted upon the magnet and induced passive eye movements. The EMF induced well-defined passive eye movements, whose directions were dependent on current polarity and amplitudes and peak velocities were dependent on current intensity and duration. Peak velocities of the EMF-induced eye movements were linearly related to amplitudes, exhibiting main sequence relationships similar to that of saccades in awake rats and eye movements induced by electrical microstimulation of the abducens nucleus in anesthetized rats. Histological examination showed that repetitive EMF stimulations did not appear to result in damages in the EOM fibers. These results validated the EMF approach as a novel tool to investigate EOM proprioceptive signals and their roles in visual localization and gaze control.

Attitudes and Knowledge of Healthcare Professionals Regarding Organ Donation. A Survey of the Saolta University Health Care Group

Organ donation saves lives and healthcare professionals (HCPs) play a vital role in that process. Therefore, the purpose of this study was to assess the attitudes and level of knowledge of HCPs regarding organ donation. An online anonymous self-administered questionnaire containing 40 questions on organ donation using google forms was created. The survey was distributed to HCPs working in the Saolta University Health Care Group. A hundred and thirty-nine responses were received giving a response rate of 11.8%. HCPs willingness to donate their organs was at 93% compared to 97% willing to receive a transplant. More HCPs understood or had knowledge of the term donation after brain death (64%) than donation after circulatory death (49%). HCPs working in intensive care knew more about the management of brain dead donors than other specialties (p<0.0001). Over 60% of HCPs when asked either disagreed or strongly disagreed with the adequacy of training in organ donation and transplant. Overall, HCPs surveyed had positive attitudes towards organ donation but there was a lack of knowledge particularly among non-intensive care professionals. This study highlights the need to increase awareness along with implementation of educational programmes among HCPs regarding organ donation and transplant.

Use of Robotic Anastomosis Competency Evaluation (RACE) for assessment of surgical competency during urethrovesical anastomosis

INTRODUCTION

We sought to evaluate the Robotic Anastomosis Competency Evaluation (RACE), a validated tool that objectively quantifies surgical skills specifically for urethrovesical anastomosis (UVA), as a tool to track progress of trainees, and to determine the predictive value of RACE.

METHODS

UVAs performed by trainees at our institution were evaluated using RACE over a period of two years. Trainees were supervised by an experienced robotic surgeon. Outcomes included trainee-related variables (RACE score, proportion of UVA performed by trainee, and suturing speed), and clinical outcomes (total UVA duration, postoperative urinary continence, and UVA-related complications). Significance was determined using linear regression analysis.

RESULTS

A total of 51 UVAs performed by six trainees were evaluated. Trainee RACE scores (19.8 to 22.3; p=0.01) and trainee proportion of UVA (67% to 80%; p=0.003) improved significantly over time. Trainee suture speed was significantly associated with RACE score (mean speed range 0.54-0.74 sutures/minute; p=0.03). Neither urinary continence at six weeks nor six months was significantly associated with RACE score (p=0.17 and p=0.15, respectively), and only one UVA-related postoperative complication was reported.

CONCLUSIONS

Trainee RACE scores improved and proportion of UVA performed by trainees increased over time. RACE can be used as an objective measure of surgical performance during training. Strict mentor supervision allowed safe training without compromising patient outcomes.

The British Neurosurgical Trainee Research Collaborative: Five years on

Since its inception in 2012, the British Neurosurgical Trainee Research Collaborative (BNTRC) has established itself as a robust example of a trainee-led research collaborative. This article summarises the work of the collaborative over its first 5 years of existence, outlining the structure, its research projects, impact and future directions.

Natural History and Predictors of Parastomal Hernia after Robot-Assisted Radical Cystectomy and Ileal Conduit Urinary Diversion

PURPOSE

We investigated the prevalence of and variables associated with parastomal hernia and its outcomes after robot-assisted radical cystectomy and ileal conduit creation for bladder cancer.

MATERIALS AND METHODS

We retrospectively reviewed the records of patients who underwent robot-assisted radical cystectomy at our institution. Parastomal hernia was defined as the protrusion of abdominal contents through the stomal defect in the abdominal wall on cross-sectional imaging. Parastomal hernia was further described in terms of patient and hernia characteristics, symptoms, management and outcomes. The Kaplan-Meier method was used to determine time to parastomal hernia and time to surgery. Multivariate stepwise logistic regression was done to evaluate variables associated with parastomal hernia.

RESULTS

A total of 383 patients underwent robot-assisted radical cystectomy and ileal conduit creation. Of the patients 75 (20%) had parastomal hernia, which was symptomatic in 23 (31%), and 11 (15%) underwent treatment. Median time to parastomal hernia was 13 months (IQR 9-22). Parastomal hernia developed in 9%, 23% and 32% of cases at 1, 2 and 3 years, respectively. Patients with parastomal hernia had a significantly higher body mass index (30 vs 28 kg/m², p = 0.02), longer overall operative time (357 vs 340 minutes, p = 0.01) and greater blood loss (325 vs 250 ml, p = 0.04). On multivariate analysis operative time (OR 1.25, 95% CI 1.21-3.90, p <0.001), a fascial defect 30 mm or greater (OR 5.23, 95% CI 2.32-11.8, p <0.001) and a lower postoperative estimated glomerular filtration rate (OR 2.17, 95% CI 1.21-3.90, p = 0.01) were significantly associated with parastomal hernia.

CONCLUSIONS

Symptoms develop in approximately a third of patients with parastomal hernia and 15% will require surgery. The risk of parastomal hernia plateaued after postoperative year 3. Longer operative time, a larger fascial defect and lower postoperative kidney function were associated with parastomal hernia.

'Finishing up' on country: challenges and compromises

A core consideration in the care of Indigenous patients at the end of life is their place of death. Dying in community can be of paramount importance to Indigenous people. This paper reports the experiences of the Top End Palliative Care Service with respect to the barriers and solutions in the return of Indigenous patients to community for end-of-life care. These barriers include not only those associated with the significant distances and remoteness in the Northern Territory but, also, spiritual and cultural factors, which often influence healthcare delivery.

Association between EMS Question Bank Completion and Passing Rates on the EMS Certification Examination

INTRODUCTION

A board review question bank was created to assist candidates in their preparation for the 2015 EMS certification examination. We aimed to describe the development of this question bank and evaluate its successes in preparing candidates to obtain EMS subspecialty board certification.

METHODS

An online question bank was developed by 13 subject matter experts who participated as item writers, representing eight different EMS fellowship programs. The online question bank consisted of four practice tests, with each of the tests comprised of 100 questions. The number of candidates who participated in and completed the question bank was calculated. The passing rate among candidates who completed the question bank was calculated and compared to the publicly reported statistics for all candidates. The relationship between candidates' performance on the question bank and subspecialty exam pass rates was determined.

RESULTS

A total of 252 candidates took at least one practice test and, of those, 225 candidates completed all four 100-question practice tests. The pass rate on the 2015 EMS certification exam was 79% (95%CI 74-85%) among candidates who completed the question bank, which is 12% higher than the overall pass rate (p = 0.003). Candidates' performance on the question bank was positively associated with overall success on the exam (X² = 75.8, p < 0.0001). Achieving a score of ≥ 70% on the question bank was associated with a higher likelihood of passing the exam (OR = 17.8; 95% CI: 8.0-39.6).

CONCLUSION

Completing the question bank program was associated with improved pass rates on the EMS certification exam. Strong performance on the question bank correlated with success on the exam.

Bilateral encephaloduroarteriosynangiosis (EDAS) in a 6-year-old female for moyamoya disease: case report and technical note with 12-year follow-up

PURPOSE

To demonstrate that despite disease progression, indirect cerebral revascularisation via EDAS for moyamoya disease is able to maintain sufficient collateral blood supply over a 12-year period.

METHODS

Case report of an individual patient with surgically managed moyamoya disease followed up with imaging and outpatient clinic assessments.

RESULTS

Follow-up imaging and assessment over 12 years concluded with a good functional and radiographic outcome.

CONCLUSION

The extensive follow-up in our case of a 6-year-old female treated with bilateral EDAS procedures for moyamoya disease demonstrates that despite disease progression over 12 years, sufficient collateral blood supply was maintained to achieve a good functional outcome.

Belief propagation in genotype-phenotype networks

Graphical models have proven to be a valuable tool for connecting genotypes and phenotypes. Structural learning of phenotype-genotype networks has received considerable attention in the post-genome era. In recent years, a dozen different methods have emerged for network inference, which leverage natural variation that arises in certain genetic populations. The structure of the network itself can be used to form hypotheses based on the inferred direct and indirect network relationships, but represents a premature endpoint to the graphical analyses. In this work, we extend this endpoint. We examine the unexplored problem of perturbing a given network structure, and quantifying the system-wide effects on the network in a node-wise manner. The perturbation is achieved through the setting of values of phenotype node(s), which may reflect an inhibition or activation, and propagating this information through the entire network. We leverage belief propagation methods in Conditional Gaussian Bayesian Networks (CG-BNs), in order to absorb and propagate phenotypic evidence through the network. We show that the modeling assumptions adopted for genotype-phenotype networks represent an important sub-class of CG-BNs, which possess properties that ensure exact inference in the propagation scheme. The system-wide effects of the perturbation are quantified in a node-wise manner through the comparison of perturbed and unperturbed marginal distributions using a symmetric Kullback-Leibler divergence. Applications to kidney and skin cancer expression quantitative trait loci (eQTL) data from different mus musculus populations are presented. System-wide effects in the network were predicted and visualized across a spectrum of evidence. Sub-pathways and regions of the network responded in concert, suggesting co-regulation and coordination throughout the network in response to phenotypic changes. We demonstrate how these predicted system-wide effects can be examined in connection with estimated class probabilities for covariates of interest, e.g. cancer status. Despite the uncertainty in the network structure, we demonstrate the system-wide predictions are stable across an ensemble of highly likely networks. A software package, geneNetBP, which implements our approach, was developed in the R programming language.

Plantar keloids: diagnostic and therapeutic issues in six patients

BACKGROUND

Keloids are benign fibro-proliferative skin lesions that very rarely occur on the soles. Because of their rarity, the diagnosis of plantar keloids can be difficult. We describe the clinical and histopathological characteristics of eight plantar keloids.

METHODS

All patients presenting with plantar keloids between 2005 and 2012 in our Dermatology unit were retrospectively included. Diagnosis was definitely established by re-reading of pathological slides in all cases. Clinical characteristics, histopathological features, treatments given and their results were collected.

RESULTS

Six patients were included. Five patients had a single plantar keloid and one had three lesions. They all were of African descent. Only one patient remembered of a previous injury at the site of the keloid. Three patients presented with associated extra-plantar keloids. In four patients, the diagnosis of keloid was not initially suspected clinically or histologically. Re-reading of the clinical photographs showed that the eight plantar keloids shared common morphological features, leading to a distinctive clinical picture, defined by a hardened lesion of rounded or polycyclic shape, with a pink surface crossed by keratotic furrows and the presence of a hyperkeratotic rim. Concerning pathological features, typical hyalinized collagen can be missing and deep fibrosis should not rule out the diagnosis of keloid. Intralesional injection of triamcinolone acetonide and orthopaedic shoes were useful. All patients who had surgical excision presented recurrence.

CONCLUSION

The knowledge of the clinical features of plantar keloids is helpful to the diagnosis. There is no well-established treatment, but supportive measures are important.

Central sleep apnea and associated Chiari malformation in children with syndromic craniosynostosis: treatment and outcome data from a supraregional national craniofacial center

OBJECT

The association of Chiari malformation Type I (CM-I) with syndromic craniosynostosis (SC) in children is well established. Central sleep apnea (CSA) may subsequently occur. However, sleep studies performed in these patients have been focused mainly on assessing the severity of obstructive sleep apnea. Therefore, the incidence and management of CSA in these patients remains poorly defined. Authors of this study aimed to assess the efficacy of foramen magnum decompression (FMD) in resolving CSA, initially detected incidentally, in a small cohort of patients with CM-I and SC.

METHODS

The clinical data for 5 children who underwent FMD for CSA at Alder Hey Children's Hospital between December 2007 and December 2009 were retrospectively analyzed. Outcomes were evaluated with respect to FMDs by utilizing pre- and postdecompression sleep studies. Of the 5 patients, 2 had Crouzon syndrome and 3 had Pfeiffer syndrome.

RESULTS

Patient age at the time of surgery ranged from 1.1 to 12.6 years (median 4.1 years). The median postoperative follow-up was 3.6 years. Sleep studies revealed that 2 children experienced a > 80% reduction in CSAs at 1.5 and 21 months after decompression. The remaining 3 children experienced a > 60% reduction in CSAs when reevaluated between 2 and 10 months after decompression. The associated central apnea index improved for all patients.

CONCLUSIONS

Findings suggested that FMD is an effective treatment modality for improving CSA in patients with SC and associated CM-I. The use of multimodal polysomnography technology may improve the evaluation and management of these patients.

Reducing surgical margins in dermatofibrosarcoma protuberans using the pathological analysis technique 'vertical modified technique': a 5-year experience

BACKGROUND

For the treatment of dermatofibrosarcoma protuberans (DFSP), wide surgical excision has been recommended, with 3-5-cm margins, including the first underlying clear fascia. Since 2006, a technical improvement in pathological analysis called the vertical modified technique (VMT) has allowed us to reduce the surgical margin without increased oncological risk.

METHODS

Between 2006 and 2011, 66 cases of DFSP were analysed in our hospital, using VMT. We reviewed patient records, considering the initial margin, total margin, number of surgeries and outcomes. Functional and aesthetic consequences were assessed by the surgeon and by the patients.

RESULTS

Mean initial margin for the first resection was 18 mm (10-30 mm). First resection allowed complete resection of the tumour in 52 cases (78.8%). Mean total surgical margin was 21.3 mm (10-60 mm). There were no cases of local tumour recurrence at a median follow-up of 30 months. Reconstruction was performed using direct sutures in 53 cases (80.3%), split-thickness skin grafts in six cases (9.1%), full-thickness skin grafts in five cases (7.6%) and flaps in two patients (3%). For 90.9% of the patients, the aesthetic result was acceptable, whereas 84.8% patients were satisfied with the functional result.

CONCLUSION

VMT reduces surgical margins and allows for extensive analysis of margins. This technique represents a safe and reliable strategy in DFSP, without increasing the risk of recurrence. The outcomes of our study have confirmed the data from the literature regarding oncological safety.

Learning in fully recurrent neural networks by approaching tangent planes to constraint surfaces

In this paper we present a new variant of the online real time recurrent learning algorithm proposed by Williams and Zipser (1989). Whilst the original algorithm utilises gradient information to guide the search towards the minimum training error, it is very slow in most applications and often gets stuck in local minima of the search space. It is also sensitive to the choice of learning rate and requires careful tuning. The new variant adjusts weights by moving to the tangent planes to constraint surfaces. It is simple to implement and requires no parameters to be set manually. Experimental results show that this new algorithm gives significantly faster convergence whilst avoiding problems like local minima.