A systematic review of combined surgery and brachytherapy approaches for children and young people with relapsed and refractory rhabdomyosarcoma (Local-REFoRMS)

Approximately one third of children with rhabdomyosarcoma relapse or have refractory disease. Treatment approaches include a combination of systemic therapies and local therapies, directed at tumour site(s). This review was conducted to evaluate the effectiveness and safety of the combination of surgery and brachytherapy as local therapy for treating children and young people with relapsed/refractory rhabdomyosarcoma. This review identified studies based on a previous systematic review looking at the treatments for children and young people under 18 years old with relapsed/refractory rhabdomyosarcoma. Studies conducted after 2000 were included. Survival outcomes, relapse rates, adverse events and functional outcomes were extracted. From 16,965 records identified in the baseline systematic review, 205 included the words 'AMORE' or 'brachytherapy', and were screened for eligibility in this substudy. Thirteen studies met the inclusion criteria for Local-REFoRMS, including over 55 relapsed and refractory rhabdomyosarcoma patients. Most studies were retrospective cohort studies conducted within Europe. Most patients had embryonal disease within the head and neck or bladder/prostate regions, and received local therapy for first relapse. Approximately one quarter of patients relapsed following surgery and brachytherapy, with local relapses occurring more than metastatic relapse. Adverse events and functional outcomes were infrequently reported, but related to the site of surgery and brachytherapy. Study quality was limited by inconsistent reporting and potential selection bias. Outcomes following surgery and brachytherapy for a selected group of relapsed and refractory rhabdomyosarcoma show reasonable benefits, but reporting was often unclear and based on small sample sizes.

Guideline for the management of Clostridioides difficile infection in pediatric patients with cancer and hematopoietic cell transplantation recipients: 2024 update

Our objective was to update a clinical practice guideline for the prevention and treatment of Clostridioides difficile infection (CDI) in pediatric patients with cancer and hematopoietic cell transplantation recipients. We reconvened an international multi-disciplinary panel. A systematic review of randomized controlled trials (RCTs) for the prevention or treatment of CDI in any population was updated and identified 31 new RCTs. Strong recommendations were made to use either oral metronidazole or oral vancomycin for non-severe CDI treatment, and to use either oral vancomycin or oral fidaxomicin for severe CDI. A strong recommendation that fecal microbiota transplantation should not be routinely used to treat CDI was also made. The panel made two new good practice statements to follow infection control practices including isolation in patients experiencing CDI, and to minimize systemic antibacterial administration where feasible, especially in patients who have experienced CDI.

A systematic review of early phase studies for children and young people with relapsed and refractory rhabdomyosarcoma: The REFoRMS-SR project

Rhabdomyosarcoma is the commonest soft tissue sarcoma in children. Around one-third of children with rhabdomyosarcoma experience relapse or have refractory disease, which is associated with a poor prognosis. This systematic review of early phase studies in pediatric relapsed/refractory rhabdomyosarcoma was conducted to inform future research and provide accurate information to families and clinicians making difficult treatment choices. Nine databases and five trial registries were searched in June 2021. Early phase studies of interventions for disease control in patients under 18 years old with relapsed/refractory rhabdomyosarcoma were eligible. No language/geographic restrictions were applied. Studies conducted after 2000 were included. Survival outcomes, response rates, quality of life and adverse event data were extracted. Screening, data extraction and quality assessment (Downs and Black Checklist) were conducted by two researchers. Owing to heterogeneity in the included studies, narrative synthesis was conducted. Of 16,965 records screened, 129 published studies including over 1100 relapsed/refractory rhabdomyosarcoma patients were eligible. Most studies evaluated systemic therapies. Where reported, 70% of studies reported a median progression-free survival ≤6 months. Objective response rate was 21.6%. Adverse events were mostly hematological. One-hundred and seven trial registry records of 99 studies were also eligible, 63 of which report they are currently recruiting. Study quality was limited by poor and inconsistent reporting. Outcomes for children with relapsed/refractory rhabdomyosarcoma who enroll on early phase studies are poor. Improving reporting quality and consistency would facilitate the synthesis of early phase studies in relapsed/refractory rhabdomyosarcoma (PROSPERO registration: CRD42021266254).

What matters to you? Engaging with children in the James Lind Alliance Children's Cancer Priority Setting Partnership

BACKGROUND

Previous priority setting exercises have sought to involve children, but in the final reporting, it is evident that few children had been engaged through the process. A primary aim in the Children's Cancer Priority Setting Partnership was to find out from children what they want research to focus on. We report on our experience to inform methods of engagement with children in future James Lind Alliance Priority Setting Partnerships and similar exercises.

METHODS

We followed the James Lind Alliance process, collecting and shortlisting questions via online surveys with adult survivors of childhood cancer, carers, and professionals, and holding a final workshop. Alongside this, a parallel process to collect and prioritise questions from children was undertaken. We created animations for parents/carers to explain the project and surveys to children, gathered questions via online surveys and held a workshop with children to identify their priorities.

RESULTS

Sixty-one children and young people with cancer and 10 siblings, aged 3-21 years, submitted 252 potential questions/topics via the surveys. Submissions were refined into 24 summary questions. These questions were discussed at a workshop with eight children; they also added more questions on topics of importance to them. Workshop participants prioritised the Top 5 questions; top priority was, 'How can we make being in hospital a better experience for children and young people? (like having better food, internet, toys, and open visiting so other family members can be more involved in the child's care)'. The Top 5 also included cancer prevention, treatments closer to home, early diagnosis, and emotional support. These questions were taken to the final workshop at which the Top 10 priorities were decided, all five children's priorities were reflected in the final Top 10.

CONCLUSIONS

We have demonstrated that it is possible to successfully involve children directly in setting priorities for future research. Future priority setting exercises on topics relevant to children, should seek to include their views. The Children's Cancer Top 10 priorities reflect the voices of children and should inform the funding of future research.

Guideline for the management of fatigue in children and adolescents with cancer or pediatric hematopoietic cell transplant recipients: 2023 update

Objective was to update a clinical practice guideline (CPG) for the management of fatigue in children and adolescents with cancer or pediatric hematopoietic cell transplant recipients. We reconvened a multi-disciplinary and multi-national panel. While the previous 2018 CPG evaluated adult and pediatric randomized controlled trials (RCTs) to manage fatigue, this 2023 update revised previous recommendations based only on pediatric RCTs. Twenty RCTs were included in the updated systematic review. Physical activity significantly reduced fatigue (standardized mean difference -0.44, 95% confidence interval -0.64 to -0.24; n = 8 RCTs). Using the 2018 recommendations as a basis, the panel continued to make strong recommendations to use physical activity, and to offer relaxation, mindfulness or both, to manage fatigue in pediatric patients. Cognitive or cognitive behavioral therapies may be offered. Pharmacological approaches should not be routinely used. The panel made a new good practice statement to routinely assess for fatigue, ideally using a validated scale.

Using Evidence-Based Medicine to Support Clinical Decision-Making in RMS

The foundations of evidence-based practice are the triad of patient values and preferences, healthcare professional experience, and best available evidence, used together to inform clinical decision-making. Within the field of rhabdomyosarcoma, collaborative groups such as the European Paediatric Soft Tissue Sarcoma Group (EpSSG) have worked to develop evidence to support this process. We have explored many of the key research developments within this review, including patient and public involvement, decision-making research, research into areas other than drug development, core outcome sets, reporting and dissemination of research, evidence synthesis, guideline development and clinical decision rules, research of research methodologies, and supporting research in RMS.

Serum Amyloid Beta Precursor Protein, Neurofilament Light, and Visinin-like Protein-1 in Rugby Players: An Exploratory Study

Concussion diagnosis is difficult and may be improved with the addition of a blood-based biomarker that indicates concussion. The purpose of this research was to investigate the capability of serum amyloid beta precursor protein (APP), neurofilament light (NfL), and visinin-like protein-1 (VILIP-1) to distinguish athletes who were diagnosed with a concussion pitch-side. An observational cross-sectional study design was used to replicate sideline concussion diagnosis. Subjects included mutually exclusive pre-match (n = 9), post-match (n = 15), and SRC (n = 7) groups. Six paired pre-and post-match subjects were analyzed for APP. APP increased significantly from pre-match (mean = 57.98 pg·mL−1, SD = 63.21 pg·mL−1) to post-match (mean = 111.37 pg·mL−1, SD = 106.89 pg·mL−1, p = 0.048) in the paired subjects. NfL was lower in the SRC group (median = 8.71 pg·mL−1, IQR = 6.09 pg·mL−1) compared to the post-match group (median = 29.60 pg·mL−1, IQR = 57.45 pg·mL−1, p < 0.001). VILIP-1 was higher in the post-match group (median = 212.18 pg·mL−1, IQR = 345.00 pg·mL−1) compared to both the pre-match (median = 32.63 pg·mL−1, IQR = 52.24 pg·mL−1), p = 0.001) and SRC (median = 30.21 pg·mL−1, IQR = 47.20 pg·mL−1), p = 0.003) groups. APP, NfL, and VILIP-1 were all able to distinguish between pre-match and post-match groups (AUROC > 0.700) but not from the SRC group (AUROC < 0.660). Our results show that APP, NfL, and VILIP-1 were not helpful in differentiating concussed from non-concussed athletes pitch-side in this study.

Quantifying biomarkers of axonal degeneration in early glaucoma to find the disc at risk

To evaluate regional axonal-related parameters as a function of disease stage in primary open angle glaucoma (POAG) and visual field (VF) sensitivity. Spectral domain optical coherence tomography was used to acquire 20° scans of POAG (n = 117) or healthy control (n = 52) human optic nerve heads (ONHs). Region specific and mean nerve fibre layer (NFL) thicknesses, border NFL and peripapillary NFL, minimum rim width (MRW)/ area (MRA) and prelamina thickness; and volume were compared across POAG disease stages and with visual field sensitivity. Differences identified between early glaucoma (EG), preperimetric glaucoma (PG) and control (C) ONHs included thinner PG prelamina regions than in controls (p < 0.05). Mean border NFL was thinner in EG (p < 0.001) and PG (p = 0.049) compared to control eyes; and EG mean, and inferior and ST, border NFL was thinner than in PG (p < 0.01). Mean, superior and inferior PG peripapillary NFL were thinner than in controls (p < 0.05), and EG ST peripapillary NFL was thinner than in PG (p = 0.023). MRW differences included: PG SN and inferior less than in controls (p < 0.05); thinner EG mean regional, inferior, nasal, and ST MRW versus PG MRW (p < 0.05). Regional border NFL, peripapillary NFL, MRW, MRA, prelamina thickness (except centre, p = 0.127) and prelamina volume (p < 0.05) were significantly associated with VF mean deviation (MD). Novel axon-derived indices hold potential as biomarkers to detect early glaucoma and identify ONHs at risk.

Protein S100B and Brain Lipid-Binding Protein Concentrations in the Serum of Recently Concussed Rugby Players

The purpose of this study was to test the ability of serum protein S100B (S100B) and brain lipid-binding protein (BLBP) to identify athletes who sustained a sports-related concussion (SRC). Subjects included a non-athlete group, whereas the rugby players were separated into two match-control and two SRC groups. The match-control <1-h group included players undergoing venipuncture within 60-min post-match, and the match-control >1-h/<8-h group included players undergoing venipuncture between 1 and 8 h post-match; the SRC <1-h group included players undergoing venipuncture within 60-min post-SRC, and the SRC >1-h/<8-h group included players undergoing venipuncture between 1 and 8 h post-SRC. Serum S100B concentrations were not significantly different (p = 0.112) among protocols. Serum BLBP was greater in the match-control <1-h group (p < 0.001) and the SRC >1-h/<8-h group (p = 0.003) compared to the non-athlete group. The ability of serum BLBP to distinguish between SRC groups and the non-athlete group was shown to be good to excellent (AUROC, >0.8; p < 0.05), and between match-control groups and the non-athlete group were shown to be excellent (AUROC, >0.9; p < 0.05). Our results show that serum S100B is not useful in distinguishing concussed or post-match athletes from non-athletes. However, serum BLBP was shown to distinguish non-athletes from post-match or concussed athletes. Serum BLBP could not distinguish between athletes experiencing an SRC within 1 h of blood draw and those participating in a contact sport.

Optimising Antimicrobial Selection and Duration in the Treatment of Febrile Neutropenia in Children

Febrile neutropenia (FN) is a frequent complication of cancer treatment in children. Owing to the potential for overwhelming bacterial sepsis, the recognition and management of FN requires rapid implementation of evidenced-based management protocols. Treatment paradigms have progressed from hospitalisation with broad spectrum antibiotics for all patients, through to risk adapted approaches to management. Such risk adapted approaches aim to provide safe care through incorporating antimicrobial stewardship (AMS) principles such as implementation of comprehensive clinical pathways incorporating de-escalation strategies with the imperative to reduce hospital stay and antibiotic exposure where possible in order to improve patient experience, reduce costs and diminish the risk of nosocomial infection. This review summarises the principles of risk stratification in FN, the current key considerations for optimising empiric antimicrobial selection including knowledge of antimicrobial resistance patterns and emerging technologies for rapid diagnosis of specific infections and summarises existing evidence on time to treatment, investigations required and duration of treatment. To aid treating physicians we suggest the key features based on current evidence that should be part of any FN management guideline and highlight areas for future research. The focus is on treatment of bacterial infections although fungal and viral infections are also important in this patient group.

How to be successful in an academic interview in pediatric oncology: A survey of Children's Oncology Group (COG) and International Society of Paediatric Oncology (SIOP) mentors

BACKGROUND

A successful academic interview has been reported as the most important factor contributing to ranking of candidates for residency. However, little published guidance exists to help a prospective oncologist or researcher give such an interview. The International Society of Paediatric Oncology (SIOP) Young Investigator (YI) Network and Children's Oncology Group (COG) YI group thus cosponsored a survey of senior investigators seeking their advice.

METHODS

An electronic survey covering aspects of the academic interview of both trainees and faculty were sent to all current/past mentors serving in the COG YI mentorship program and those registered as mentors in the SIOP YI mentorship program. The responses were quantitatively and qualitatively analyzed.

RESULTS

The response rate was 43.7% (118/270) from 25 countries. Majority of United States (US) interviewers (86.8%) conducted interviews individually, while 74% of non-US interviewers conducted panel interviews or both types equally (P < .001). Majority of interviewers (83.4%) at least occasionally contacted colleagues for off the record opinions on candidates, and 40.9% conducted an internet or social media search. Enthusiasm for the job (97.2%) and being a team player (95.3%) were the qualities most rated as at least moderately important, while a priority for work-life balance (45.4%) and having interests/hobbies outside of medicine (29.2%) were considered less important. Interviewers provided interview questions, tips for candidates, and key pitfalls to avoid.

DISCUSSION

Candidates should prepare for their academic interviews in advance, be enthusiastic and honest when giving responses. Detailed guidance for those applying at different career stages and in different countries are provided.

COVID-19 and children with cancer: Parents' experiences, anxieties and support needs

BACKGROUND

Children with cancer were designated as clinically extremely vulnerable if they were to contract SARS-CoV-2 due to immune suppression in the early phase of the COVID-19 pandemic. Our aim was to explore experiences, information and support needs, and decision making of parents with a child with cancer in response to this phase in the United Kingdom.

METHODS

Parents of a child with cancer completed a survey at a time when the UK moved into a period of 'lockdown'. An online survey was developed by the research team to capture parents' experiences, information and support needs, and decision making, using closed statements and open text boxes. Descriptive quantitative analyses and qualitative thematic content analysis were undertaken.

FINDINGS

One hundred seventy-one parents/caregivers completed the survey. Eighty-five percent were worried about the virus and they were vigilant about the virus (92%) or cancer symptoms (93.4%). For two-thirds (69.6%), hospital was no longer considered a safe place. Eight overarching themes were identified related to the virus: (a) risk of infection; (b) information, guidance and advice; (c) health care provision; (d) fears and anxieties; or related to lockdown/isolation: (e) psychological and social impact; (f) keeping safe under lockdown; (g) provisions and dependence; and (h) employment and income.

CONCLUSIONS

This is the first study, to the best of our knowledge, to report experiences of parents of a child with cancer during the SARS-CoV-2/COVID-19 pandemic. The majority of parents were worried about SARS-CoV-2 and transmitting the virus to their child. Hospital was no longer perceived to be a safe place, and parents were worried about suboptimal cancer care. Parents described fear and anxiety and the psychological, social and economic impact of isolation.

A systematic review of evidence for and against routine surveillance imaging after completing treatment for childhood extracranial solid tumors

BACKGROUND

Regular off-treatment imaging is often used to assess for recurrence of disease after childhood cancer treatment. It is unclear if this increases survival, or what burden surveillance places on patients, families, or health-care services. This systematic review examines the impact of routine surveillance imaging after treatment of pediatric extracranial solid tumors.

METHODS

Collaborative patient and public involvement informed the design and interpretation of this work. Thirteen electronic databases, conference proceedings, and trial registries were searched alongside reference list checking and forward citation searching from 1990 onwards. Studies were screened and data were extracted by two researchers. Risk of bias was assessed using a modified ROBINS-I tool. Relevant outcomes were overall survival, psychological distress indicators, number of imaging tests, cost-effectiveness, and qualitative data regarding experiences of surveillance programs. PROSPERO (CRD42018103764).

RESULTS

Of 17 727 records identified, 55 studies of 10 207 patients were included. All studies used observational methods. Risk of bias for all except one study was moderate, serious, or critical. Data were too few to conduct meta-analysis; however, narrative synthesis was performed. Surveillance strategies varied, and poorly reported, involving many scans and substantial radiation exposure (eg, neuroblastoma, median 133.5 mSv). For most diseases, surveillance imaging was not associated with increased overall survival, with the probable exception of Wilms tumor. No qualitative or psychological distress data were identified.

CONCLUSIONS

At present, there is insufficient evidence to evaluate the effects of routine surveillance imaging on survival in most pediatric extracranial solid tumors. More high-quality data are required, preferably through randomized controlled trials with well-conducted qualitative elements.

From the sticky floor to the glass ceiling and everything in between: protocol for a systematic review of barriers and facilitators to clinical academic careers and interventions to address these, with a focus on gender inequality

BACKGROUND

Gender inequality within academic medicine and dentistry is a well-recognised issue, but one which is not completely understood in terms of its causes, or interventions to facilitate equality. This systematic review aims to identify, critically appraise, and synthesise the literature on facilitators and barriers to progression through a clinical academic career across medicine and dentistry. It will also explore interventions developed to increase recruitment and retention to clinical academic careers, with a particular focus on gender inequality.

METHODS

The search will cover five databases (MEDLINE (including MEDLINE Epub Ahead of Print, MEDLINE In-Process & Other Non-Indexed Citations, and MEDLINE Daily), Cochrane Controlled Register of Trials (CENTRAL), PsycINFO, and Education Resource Information Center (ERIC)), reference lists, and forward citation searching. We will include studies of doctors, dentists, and/or those with a supervisory role over their careers, with or without an academic career. Outcomes will be study defined, but relate to success rates of joining or continuing within a clinical academic career, including but not limited to success in gaining funding support, proportion of time spent in academic work, and numbers of awards/higher education qualifications, as well as experiences of professionals within the clinical academic pathway. Study quality will be assessed using the Cochrane risk of bias tool for randomised controlled trials, the Newcastle-Ottawa tool for non-randomised studies, and the QARI tool for qualitative studies. Detailed plans for screening, data extraction, and analysis are provided within this protocol.

DISCUSSION

This systematic review is situated within a larger project evaluating gender inequalities in clinical academic careers. This review will identify and synthetize barriers, facilitators, and interventions addressing gender inequalities in clinical academia. Our findings will increase awareness of inequalities in clinical academic careers through informing clinical academics, regulators and funders of the issues involved, and potential interventions to counteract these. Results will be published in a peer-reviewed journal.

SYSTEMATIC REVIEW REGISTRATION

Open Science Framework: https://osf.io/mfy7a.

Interventions aiming to reduce time to antibiotics (TTA) in patients with fever and neutropenia during chemotherapy for cancer (FN), a systematic review

Purpose

Multiple interventions have been developed aiming to reduce time to antibiotics (TTA) in patients with fever and neutropenia (FN) following chemotherapy for cancer. We evaluated their effect to reduce TTA and their impact on important clinical outcomes in a systematic review.

Methods

The search covered seven databases. Biases and quality of studies were assessed with the Risk of Bias in Non-randomized Studies of Interventions (ROBINS-I) tool. Interventions could be implemented in any setting and performed by any person included in the FN management. Absolute change of TTA was the primary outcome. Registration: PROSPERO (CRD42018092948).

Results

Six thousand two hundred ninety-six titles and abstracts were screened, 177 studies were retrieved and 30 studies were included. Risk of bias was moderate to serious in 28 studies and low in two studies. All but one study reported a reduction of TTA after the intervention. Various types of interventions were implemented; they most commonly aimed at professionals. Most of the studies made more than one single intervention.

Conclusion

This review may help centers to identify their specific sources of delay and barriers to change and to define what intervention may be the best to apply. This review supports the assertion that TTA can be considered a measure of quality of care, emphasizes the importance of education and training, and describes the very different interventions which have effectively reduced TTA.

Electronic supplementary material

The online version of this article (10.1007/s00520-019-05056-w) contains supplementary material, which is available to authorized users.

Does routine surveillance imaging after completing treatment for childhood solid tumours cause more harm than good? A systematic review and meta-analysis protocol

BACKGROUND

This systemic review aims to synthesise the current literature surrounding off-therapy surveillance imaging in children and young people with extra-cranial solid tumours, with a view to establishing if routine imaging studies after treatment for childhood cancer increase overall survival, increase the psychological distress caused to patients and families, result in other harms to patients and are cost-effective strategies. Within this manuscript, we also describe how patient and public involvement has impacted upon the protocol.

METHODS

The search will cover thirteen different databases, key conference proceedings and trial registers, as well as reference lists and forward citations of included papers. Prominent authors/clinicians in the field will be contacted. A full search strategy is provided. The study designs to be included in the review will be added in an iterative way (RCTs, quasi-randomised trials, prospective cohorts and retrospective cohorts). Qualitative studies will also be eligible for inclusion. We will include studies which examine a programme of surveillance imaging that aims to detect relapse in children or young people up to age 25 years who have completed treatment for a malignant extracranial solid tumour and have no evidence of active and ongoing disease at end of treatment. The primary outcome is overall survival, with secondary outcomes including psychological distress indicators, number of imaging tests performed, other harms of imaging and cost-effectiveness measures. Studies will be screened and data extracted by two researchers. Studies will be critically appraised using a stratified version of the ROBINS-I tool. Where appropriate, data will be synthesised using a random effects meta-analysis. A detailed analysis plan, including assessment of heterogeneity and publication bias, is provided.

DISCUSSION

The aim of routine surveillance imaging is to detect recurrence of disease before clinical symptoms and signs develop. Some studies have suggested that most relapses of childhood cancer are detected due to clinical symptoms or signs, particularly in those with extra-cranial solid tumours, and when these relapses are detected by imaging, there is no increase in survival. This review aims to establish whether routine surveillance imaging is beneficial, as well as evaluating the potential negative impacts of surveillance programmes.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42018103764.

Fifteen minute consultation: Fever in children being treated for cancer

Fever is a common symptom in children receiving treatment for cancer. Clinicians and families are most concerned about febrile neutropenia, though non-neutropenic fever often causes more challenging treatment dilemmas. This article provides a structured approach to the initial assessment, examination, investigation and risk assessment of children with fever during treatment for childhood cancer. Non-neutropenic fever in children with cancer is not well researched. There are no systematic reviews of its management and no National Institute for Health and Care Excellence (NICE) (or other international) guidance about what to do. Features to consider when managing non-neutropenic fever are discussed. Febrile neutropenia, meanwhile, is an oncological emergency and requires management using standard sepsis principles including administration of broad-spectrum antibiotics. Relevant NICE guidance provides a clear structure for treatment. Ongoing management depends on the response to initial treatment.

Quest for certainty regarding early discharge in paediatric low-risk febrile neutropenia: a multicentre qualitative focus group discussion study involving patients, parents and healthcare professionals in the UK

OBJECTIVES

A systematic review of paediatric low-risk febrile neutropenia found that outpatient care is safe, with low rates of treatment failure. However, this review, and a subsequent meta-ethnography, suggested that early discharge of these patients may not be acceptable to key stakeholders. This study aimed to explore experiences and perceptions of patients, parents and healthcare professionals involved in paediatric febrile neutropenia care in the UK.

SETTING

Three different centres within the UK, purposively selected from a national survey on the basis of differences in their service structure and febrile neutropenia management.

PARTICIPANTS

Thirty-two participants were included in eight focus group discussions.

PRIMARY OUTCOMES

Experiences and perceptions of paediatric febrile neutropenia care, including possible future reductions in therapy.

RESULTS

Participants described a quest for certainty, in which they attempted to balance the uncertainty involved in understanding, expressing and negotiating risk with the illusion of certainty provided by strict protocols. Participants assessed risk using both formal and informal stratification tools, overlaid with emotional reactions to risk and experiences of risk within other situations. The benefits of certainty provided by protocols were counterbalanced by frustration at their strict constraints. The perceived benefits and harms of previous inpatient care informed participants' appraisals of future treatment strategies.

CONCLUSIONS

This study highlighted the previously underestimated harms of admission for febrile neutropenia and the paternalistic nature of decision making, along with the frustrations and challenges for all parties involved in febrile neutropenia care. It demonstrates how the same statistics, generated by systematic reviews, can be used by key stakeholders to interpret risk differently, and how families in particular can view the harms of therapeutic options as different from the outcomes used within the literature. It justifies a reassessment of current treatment strategies for these children and further exploration of the potential to introduce shared decision making.

Paired learning – improving collaboration between clinicians and managers

Purpose

Close collaboration between NHS clinicians and managers is essential in providing effective healthcare, but relationships between the two groups are often poor. Paired learning is a peer-peer buddying tool that can break down barriers, increase knowledge and change attitudes. Paired learning has been used with doctors and managers but not for multi-professional clinicians. The purpose of this paper is to assess whether a paired learning programme (PLP) can improve knowledge and attitudes between multi-professional NHS clinicians and managers.

Design/methodology/approach

A PLP pairing clinicians and managers over a four-month period to participate in four buddy meetings and three group meetings was delivered. A mixed methods study was completed which collected quantitative and qualitative data in the form of pre- and post-course questionnaires and focus group discussions.

Findings

Participants reported increased understanding, changed attitudes and better communication between clinicians and managers following the PLP. Self-rated knowledge increased across all domains but was only statistically significant for ability to engage, ability to establish shared goals and knowledge of decision-making processes.

Research limitations/implications

This paper highlights the value of paired learning in encouraging collaboration between clinicians and managers but is of a small size. The PLP did not provide enough data to examine relationships and interaction between clinicians and managers, this should be considered in any future work.

Originality/value

To the authors’ knowledge, this is the only published paper showing data from a PLP involving multi-disciplinary health professionals.

The optical detection of retinal ganglion cell damage

We provide an overview of developments in the use optical coherence tomography (OCT) imaging for the detection of retinal ganglion cell (RGC) damage in vivo that avoid use of any exogenous ligands to label cells. The method employs high-resolution OCT using broad spectral light sources to deliver axial resolution of under 5 μm. The resolution approximates that of cellular organelles, which undergo degenerative changes that progress to apoptosis as a result of axon damage. These degenerative changes are manifest as the loss of RGC dendrites and fragmentation of the subcellular network of organelles, in particular, the mitochondria that support dendritic structure. These changes can alter the light-scattering behavior of degenerating neurons. Using OCT imaging techniques to identify these signals in cultured neurons, we have demonstrated changes in cultured cells and in retinal explants. Pilot studies in human glaucoma suggest that similar changes are detectable in the clinical setting. High-resolution OCT can be used to detect optical scatter signals that derive from the RGC/inner plexiform layer and are associated with neuronal damage. These findings suggest that OCT instruments can be used to derive quantitative measurements of RGC damage. Critically, these signals can be detected at an early stage of RGC degeneration when cells could be protected or remodeled to support visual recovery.

Quantitative analysis of three-dimensional fibrillar collagen microstructure within the normal, aged and glaucomatous human optic nerve head

The aim of this study was to quantify connective tissue fibre orientation and alignment in young, old and glaucomatous human optic nerve heads (ONH) to understand ONH microstructure and predisposition to glaucomatous optic neuropathy. Transverse (seven healthy, three glaucomatous) and longitudinal (14 healthy) human ONH cryosections were imaged by both second harmonic generation microscopy and small angle light scattering (SALS) in order to quantify preferred fibre orientation (PFO) and degree of fibre alignment (DOFA). DOFA was highest within the peripapillary sclera (ppsclera), with relatively low values in the lamina cribrosa (LC). Elderly ppsclera DOFA was higher than that in young ppsclera (p < 0.00007), and generally higher than in glaucoma ppsclera. In all LCs, a majority of fibres had preferential orientation horizontally across the nasal–temporal axis. In all glaucomatous LCs, PFO was significantly different from controls in a minimum of seven out of 12 LC regions (p < 0.05). Additionally, higher fibre alignment was observed in the glaucomatous inferior–temporal LC (p < 0.017). The differences between young and elderly ONH fibre alignment within regions suggest that age-related microstructural changes occur within the structure. The additional differences in fibre alignment observed within the glaucomatous LC may reflect an inherent susceptibility to glaucomatous optic neuropathy, or may be a consequence of ONH remodelling and/or collapse.

Aminoaciduria in the prediction of ifosfamide-induced tubulopathy after childhood cancer: a feasibility study

BACKGROUND

Ifosfamide, an alkylating agent used widely in the treatment of childhood malignancy, can cause many side effects including a proximal tubulopathy. Studies suggest that aminoaciduria is seen most commonly of all the biochemical abnormalities of ifosfamide-induced tubulopathy. A recent systematic review has found a paucity of data regarding the value of early markers indicating clinically significant tubulopathy. We undertook a pilot study to determine the feasibility of examining whether patients can be risk-stratified on the basis of aminoaciduria for the development of future significant ifosfamide-induced tubulopathy, to allow the evolution of appropriate follow-up strategies. We also aimed to define accrual rates, costs and clinical demands for a future larger study.

METHODS

This observational study recruited 21 patients from the Leeds Paediatric Oncology service. The medical notes of each patient were reviewed for demographic and clinical data. Simultaneous samples of blood and urine were obtained.

RESULTS

The investigations in the feasibility study were acceptable to patients and were minimally demanding on both clinical and laboratory staff. Financially, the cost per patient was minimal. This study was not powered to detect significant associations with TmP/GFR (ratio of renal tubular maximum reabsorption rate of phosphate to glomerular filtration rate), growth and electrolyte supplementation. However, all patients with minimal aminoaciduria (≤2 elevated urinary amino acids) had normal TmP/GFR and no need for electrolyte supplementation.

CONCLUSIONS

This pilot study has shown that a larger study is feasible and may provide clinically useful data to change current practice. This should aim to establish whether the number of abnormal amino acids or the degree of abnormality is most significant in predicting clinically significant proximal tubulopathy.

Systematic review of reduced therapy regimens for children with low risk febrile neutropenia

PURPOSE

Reduced intensity therapy for children with low-risk febrile neutropenia may provide benefits to both patients and the health service. We have explored the safety of these regimens and the effect of timing of discharge.

METHODS

Multiple electronic databases, conference abstracts and reference lists were searched. Randomised controlled trials (RCT) and prospective observational cohorts examining the location of therapy and/or the route of administration of antibiotics in people younger than 18 years who developed low-risk febrile neutropenia following treatment for cancer were included. Meta-analysis using a random effects model was conducted. I (2) assessed statistical heterogeneity not due to chance.

REGISTRATION

PROSPERO (CRD42014005817).

RESULTS

Thirty-seven studies involving 3205 episodes of febrile neutropenia were included; 13 RCTs and 24 prospective observational cohorts. Four safety events (two deaths, two intensive care admissions) occurred. In the RCTs, the odds ratio for treatment failure (persistence, worsening or recurrence of fever/infecting organisms, antibiotic modification, new infections, re-admission, admission to critical care or death) with outpatient treatment was 0.98 (95% confidence interval (95%CI) 0.44-2.19, I (2) = 0 %) and with oral treatment was 1.05 (95%CI 0.74-1.48, I (2) = 0 %). The estimated risk of failure using outpatient therapy from all prospective data pooled was 11.2 % (95%CI 9.7-12.8 %, I (2) = 77.2 %) and using oral antibiotics was 10.5 % (95%CI 8.9-12.3 %, I (2) = 78.3 %). The risk of failure was higher when reduced intensity therapies were used immediately after assessment, with lower rates when these were introduced after 48 hours.

CONCLUSIONS

Reduced intensity therapy for specified groups is safe with low rates of treatment failure. Services should consider how these can be acceptably implemented.

Protocol for a systematic review of reductions in therapy for children with low-risk febrile neutropenia

BACKGROUND

Febrile neutropenia is a common complication of therapy in children with cancer. Some patients are at low risk of complications, and research has considered reduction in therapy for these patients. A previous systematic review broadly considered whether outpatient treatment and oral antibiotics were safe in this context and concluded that this was likely to be the case. Since that review, there has been further research in this area. Therefore, we aim to provide a more robust answer to these questions and to additionally explore whether the exact timing of discharge, including entirely outpatient treatment, has an impact on outcomes.

METHODS/DESIGN

The search will cover MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, EMBASE, CDSR, CENTRAL, LILACS, HTA and DARE. A full search strategy is provided. Key conference proceedings and reference lists of included papers will be hand searched. Prominent authors/clinicians in the field will be contacted. We will include randomised and quasi-randomised controlled trials along with prospective single-arm studies that examine the location of therapy and/or the route of administration of antibiotics in children or young adults (aged less than 18 years) who attend paediatric services with fever and neutropenia due to treatment for cancer and are assessed to be at low risk of medical complications. Studies will be screened and data extracted by one researcher and independently checked by a second. All studies will be critically appraised using tools appropriate to the study design. Data from randomised controlled trials (RCTs) will be combined to provide comparative estimates of treatment failure, safety and adequacy. Information from quasi-randomised trials and single-arm studies will provide further data on the safety and adequacy of regimes. Random effects meta-analysis will be used to combine studies. A detailed analysis plan, including assessment of heterogeneity and publication bias, is provided.

DISCUSSION

This study will aim to specifically define the features of a low-risk strategy that will maintain levels of safety and adequacy equivalent to those of traditional treatments. This will both inform the development of services and provide patients and families with data to help them make an informed decision about care.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42014005817.

Improving accuracy and efficiency of mutual information for multi-modal retinal image registration using adaptive probability density estimation

Mutual information (MI) is a popular similarity measure for performing image registration between different modalities. MI makes a statistical comparison between two images by computing the entropy from the probability distribution of the data. Therefore, to obtain an accurate registration it is important to have an accurate estimation of the true underlying probability distribution. Within the statistics literature, many methods have been proposed for finding the 'optimal' probability density, with the aim of improving the estimation by means of optimal histogram bin size selection. This provokes the common question of how many bins should actually be used when constructing a histogram. There is no definitive answer to this. This question itself has received little attention in the MI literature, and yet this issue is critical to the effectiveness of the algorithm. The purpose of this paper is to highlight this fundamental element of the MI algorithm. We present a comprehensive study that introduces methods from statistics literature and incorporates these for image registration. We demonstrate this work for registration of multi-modal retinal images: colour fundus photographs and scanning laser ophthalmoscope images. The registration of these modalities offers significant enhancement to early glaucoma detection, however traditional registration techniques fail to perform sufficiently well. We find that adaptive probability density estimation heavily impacts on registration accuracy and runtime, improving over traditional binning techniques.

Observation of electron-antineutrino disappearance at Daya Bay

The Daya Bay Reactor Neutrino Experiment has measured a nonzero value for the neutrino mixing angle θ(13) with a significance of 5.2 standard deviations. Antineutrinos from six 2.9 GWth reactors were detected in six antineutrino detectors deployed in two near (flux-weighted baseline 470 m and 576 m) and one far (1648 m) underground experimental halls. With a 43,000 ton-GWth-day live-time exposure in 55 days, 10,416 (80,376) electron-antineutrino candidates were detected at the far hall (near halls). The ratio of the observed to expected number of antineutrinos at the far hall is R=0.940±0.011(stat.)±0.004(syst.). A rate-only analysis finds sin(2)2θ(13)=0.092±0.016(stat.)±0.005(syst.) in a three-neutrino framework.

Psychosocial Treatment to Improve Resilience and Reduce Impairment in Youth With Tics: An Intervention Case Series of Eight Youth

Background: Many youth with tic disorders experience distress about having tics and how others may perceive them. Such symptoms are often more impairing and distressing than the tics themselves and negatively impact self-concept, psychosocial functioning, and quality of life. Objective: Although there exist pharmacological and behavioral treatments that target the frequency and severity of tics, no intervention has been developed specifically to help youth with tics cope with their condition and limit associated functional impairment and distress. With this in mind, we report an intervention case series of eight youth (ages 8–16 years) supporting the initial efficacy of a cognitive-behavioral therapy program entitled “Living with Tics” that promotes coping and resiliency among youth with tics. Method: Eight youth with a principal diagnosis of a tic disorder (i.e., Tourette syndrome [N = 6]; Chronic Tic Disorder [N = 2]) and associated psychosocial impairment participated. Assessments were conducted at screening, pretreatment, and posttreatment by trained raters. Treatment consisted of 10 weekly individual psychotherapy session focused on improving coping with having tics. Results: Six of eight youth were considered treatment responders. On average, participants exhibited meaningful reductions in tic-related impairment, anxiety, and overall tic severity as well as improvements in self-concept and quality of life. Conclusions: These data provide preliminary evidence for conducting a larger controlled trial to examine the utility of the Living with Tics psychosocial intervention for promoting adaptive functioning among youth with tics.

Muscle histology vs MRI in Duchenne muscular dystrophy

OBJECTIVE

There are currently no effective treatments to halt the muscle breakdown in Duchenne muscular dystrophy (DMD), although genetic-based clinical trials are being piloted. Most of these trials have as an endpoint the restoration of dystrophin in muscle fibers, hence requiring sufficiently well-preserved muscle of recruited patients. The choice of the muscles to be studied and the role of noninvasive methods to assess muscle preservation therefore require further evaluation.

METHODS

We studied the degree of muscle involvement in the lower leg muscles of 34 patients with DMD >8 years, using muscle MRI. In a subgroup of 15 patients we correlated the muscle MRI findings with the histology of open extensor digitorum brevis (EDB) muscle biopsies. Muscle MRI involvement was assigned using a scale 0-4 (normal-severe).

RESULTS

In all patients we documented a gradient of involvement of the lower leg muscles: the posterior compartment (gastrocnemius > soleus) was most severely affected; the anterior compartment (tibialis anterior/posterior, popliteus, extensor digitorum longus) least affected. Muscle MRI showed EDB involvement that correlated with the patient's age (p = 0.055). We show a correlation between the MRI and EDB histopathologic changes, with MRI 3-4 grades associated with a more severe fibro-adipose tissue replacement. The EDB was sufficiently preserved for bulk and signal intensity in 18/22 wheelchair users aged 10-16.6 years.

CONCLUSION

This study provides a detailed correlation between muscle histology and MRI changes in DMD and demonstrates the value of this imaging technique as a reliable tool for the selection of muscles in patients recruited into clinical trials.

Transretinal degeneration in ageing human retina: a multiphoton microscopy analysis

AIM

Retinal cell remodelling has been reported as a consistent feature of ageing. However, the degree to which this results in transretinal degeneration is unclear. To address this, the authors used multiphoton microscopy to quantify retinal degeneration in post-mortem human eyes of two age groups.

METHODS

Retinas from six young subjects (18-33 years old) and six older subjects (74-90 years old) were prepared as wholemount preparations. All retinas were stained with 4,6-diamidino-2-phenylindole and imaged by multiphoton confocal microscopy to quantify neuron densities in the retinal ganglion cell layer (RGCL), inner nuclear layer (INL) and outer nuclear layer (ONL). Neurons were counted using automated cell identification algorithms. All retinas were imaged hydrated to minimise tissue artefacts.

RESULTS

In both groups, 56% of the area within the central 4 mm eccentricity and 27% of the area with eccentricity between 4 mm and 7 mm were imaged. Compared with young subjects, the peak RGCL neuron loss in the aged subjects (25.5%) was at 1 mm eccentricity. INL and ONL neuron densities significantly decreased at 1-2 mm eccentricity (8.7%) and 0.5-4 mm eccentricity (15.6%) respectively (P <0.05). The reduction in neuron density in the INL corresponded, spatially, to the region with the greatest neuron loss in the RGCL and ONL.

CONCLUSIONS

This is the first study to correlate neurodegeneration in different populations of cells in the ageing retinas. These data confirm that the greatest neuronal loss occurs in the RGCL and ONL in human ageing retinas, whereas the INL is relatively preserved.

Mouse models of dominant optic atrophy: what do they tell us about the pathophysiology of visual loss?

Dominant optic atrophy (DOA) is the most common inherited optic neuropathy affecting one in every 12,000 people. It presents with bilateral visual loss, central visual fields defects, colour vision disturbance and optic disc pallor. OPA1 has been identified as the responsible gene and its locus mapped to chromosome 3q28-q29. Mutations in this gene are responsible for the clinical phenotype in over 70% of patients with DOA. Histopathological studies in tissues from patients reveal loss of retinal ganglion cells but the paucity of viable human tissue has raised the importance of an animal model to study the pathophysiology of the disease. In the last decade considerable work has gone into the generation of animal, most notably mouse, models of Opa1 DOA. Two murine models of DOA have been published, designated B6;C3-Opa1(Q285STOP) and B6;C3-Opa1(329-355del) and they provide valuable insights with respect to neurological and visual phenotyping, mitochondrial dysfunction, optic nerve and axonal changes, retinal ganglion cell depletion and dendritic atrophy. Here we summarise the current state of knowledge of the mechanisms of disease based on data from these models of Opa1 DOA.

BMP signalling permits population expansion by preventing premature myogenic differentiation in muscle satellite cells

Satellite cells are the resident stem cells of adult skeletal muscle, supplying myonuclei for homoeostasis, hypertrophy and repair. In this study, we have examined the role of bone morphogenetic protein (BMP) signalling in regulating satellite cell function. Activated satellite cells expressed BMP receptor type 1A (BMPR-1A/Alk-3) and contained phosphorylated Smad proteins, indicating that BMP signalling is operating during proliferation. Indeed, exogenous BMP4 stimulated satellite cell division and inhibited myogenic differentiation. Conversely, interfering with the interactions between BMPs and their receptors by the addition of either the BMP antagonist Noggin or soluble BMPR-1A fragments, induced precocious differentiation. Similarly, blockade of BMP signalling by siRNA-mediated knockdown of BMPR-1A, disruption of the intracellular pathway by either Smad5 or Smad4 knockdown or inhibition of Smad1/5/8 phosphorylation with Dorsomorphin, also caused premature myogenic differentiation. BMP signalling acted to inhibit the upregulation of genes associated with differentiation, in part, through regulating Id1. As satellite cells differentiated, Noggin levels increased to antagonise BMP signalling, since Noggin knockdown enhanced proliferation and impeded myoblast fusion into large multinucleated myotubes. Finally, interference of normal BMP signalling after muscle damage in vivo perturbed the regenerative process, and resulted in smaller regenerated myofibres. In conclusion, BMP signalling operates during routine satellite cell function to help coordinate the balance between proliferation and differentiation, before Noggin is activated to antagonise BMPs and facilitate terminal differentiation.

Topography of neuron loss in the retinal ganglion cell layer in human glaucoma

AIM

To determine if retinal ganglion cell (RGC) loss influences the loss of surrounding RGCs to generate clustered patterns of cell death in human glaucoma. It is hypothesised that retinal ganglion cell loss accelerates the loss of surrounding cells to generate, at a local, cellular scale, clustered patterns of retinal of RGC death. The absence of these interactions would result in a diffuse pattern RGC loss.

METHOD

Six glaucomatous retinas (67-83 years old) and six age-matched control retinas (61-89 years old) were prepared as wholemounts and stained by 4',6-diamidino-2-phenylindole (DAPI) solution (3 microg/ml in PBS). An area corresponding to central 14 degrees of the visual field was imaged. The nearest-neighbour distribution was determined for cells in both normal and glaucomatous RGCL.

RESULTS

Clustered RGC loss in human glaucoma was observed on a background of diffuse loss. The mean nearest-neighbour distance (NND) of the glaucomatous retinas was significantly higher than with controls (p<0.001). The distribution of NND in glaucomatous retinas was skewed to the higher values with a higher positive kurtosis relative to controls. The quantitative analysis of the pattern of cell loss is supported by the visual inspection of the patterns of cell loss.

DISCUSSION

The nearest-neighbour analysis is consistent with the presence of two patterns of cell loss in the RGCL in glaucoma. While the diffuse of cell loss can account for an overall reduction in the RGC population, an additional non-random pattern is consistent with the hypothesis that RGC loss has a local influence on the viability of surrounding cells.

Comparative analysis of antisense oligonucleotide sequences for targeted skipping of exon 51 during dystrophin pre-mRNA splicing in human muscle

Duchenne muscular dystrophy (DMD) is caused by mutations in the dystrophin gene that result in the absence of functional protein. In the majority of cases these are out-of-frame deletions that disrupt the reading frame. Several attempts have been made to restore the dystrophin mRNA reading frame by modulation of pre-mRNA splicing with antisense oligonucleotides (AOs), demonstrating success in cultured cells, muscle explants, and animal models. We are preparing for a phase I/IIa clinical trial aimed at assessing the safety and effect of locally administered AOs designed to inhibit inclusion of exon 51 into the mature mRNA by the splicing machinery, a process known as exon skipping. Here, we describe a series of systematic experiments to validate the sequence and chemistry of the exon 51 AO reagent selected to go forward into the clinical trial planned in the United Kingdom. Eight specific AO sequences targeting exon 51 were tested in two different chemical forms and in three different preclinical models: cultured human muscle cells and explants (wild type and DMD), and local in vivo administration in transgenic mice harboring the entire human DMD locus. Data have been validated independently in the different model systems used, and the studies describe a rational collaborative path for the preclinical selection of AOs for evaluation in future clinical trials.

Measurement of intraocular pressure (IOP) in chickens using a rebound tonometer: quantitative evaluation of variance due to position inaccuracies

Intraocular pressure (IOP), an important risk factor for glaucoma, is a continuous trait determined by a complex set of genetic and environmental factors that are largely unknown. Genetic studies in laboratory animals may facilitate the identification of genes that affect IOP. We examined the use of the rebound tonometer for measuring IOP in non-anaesthetised birds, along with the device's robustness to alignment errors. Calibration curves were obtained by measuring the IOP of cannulated chicken eyes with the rebound tonometer over a range of pressures. To simulate different types of alignment errors that might be expected with measurement of IOP in alert chickens, for some calibrations the tonometer was positioned (1) at various distances from the cornea, (2) laterally displaced from the visual axis, or (3) angled away from the visual axis. In vivo measurements were taken on three-week-old alert chickens from a layer line, a broiler line, and a layer-broiler "advanced intercross line" (AIL) designed to facilitate QTL mapping. The rebound tonometer showed excellent linearity (R2=0.95-0.99) during calibration, as well as robustness to variation in the probe-to-cornea distance over the range 3-5mm and to lateral displacement over the range 0-2mm. However, the tonometer appeared less robust to off-axis misalignment over the range 0-20 degrees (P<0.05). Also, the slope of calibration curves sometimes differed between eyes (P<0.001), presumably reflecting differences in ocular structure. The IOP measured in non-anaesthetised three-week-old AIL chickens was 17.51+/-0.13 mmHg (mean+/-S.E.; N=105 birds). IOP was significantly associated with corneal thickness (P<0.05) and body weight (P<0.001) in a regression model. Replicate measurements were necessary in order to gauge IOP accurately in individual birds; a series of seven tonometry sessions over a 12-h period during the light phase of the light/dark cycle permitted IOP to be measured with a 95% CI of +/-0.7 mmHg. IOP did not differ significantly between the broiler and layer chicken lines which served as the progenitor lines for the AIL. In conclusion, the rebound tonometer permits rapid estimation of IOP in chickens and is well tolerated. The small alignment errors that are expected when taking measurements in non-anaesthetised animals are unlikely to affect accuracy. Since high IOP is a major risk factor for glaucoma, identifying QTL controlling IOP may offer future health benefits. However, our preliminary findings highlight several obstacles to mapping such QTL using the chicken advanced intercross line evaluated here.

Stem cells to treat muscular dystrophies

Stem cells, capable of giving rise to both differentiated skeletal muscle and to more stem cells, would be ideal for treating chronic myopathies such as Duchenne Muscular Dystrophy. However, although satellite cells have been shown to be functional muscle stem cells in animal models, other muscle or non-muscle stem cells are far less capable of contributing to skeletal muscle regeneration. This review discusses recent work on stem cell contribution to skeletal muscle regeneration and highlights the problems to be overcome before stem cell treatment of muscle diseases may become a possibility.

Digital imaging of the optic nerve head: monoscopic and stereoscopic analysis

AIMS

To compare monoscopic and stereoscopic assessment of the optic disc using novel software for the digital stereoscopic analysis of optic disc stereopairs.

METHODS

Software was developed for the stereoscopic display of digital optic disc images using an interlaced display method. Neuroretinal rim width was determined at 10 degree intervals around the optic disc using a custom (stereoscopic) cursor whose depth was adjusted to that of Elschnig's rim. Measurements were taken, first viewing the disc monoscopically and at a separate sitting, stereoscopically.

RESULTS

Measurements were made in 35 eyes from 35 patients (1260 estimates for each observer) using three observers. The mean cup to disc ratio (CDR) ranged from 0.57 to 0.66 (SD 0.13-0.14) for monoscopic viewing compared with 0.64 to 0.69 (SD 0.12-0.14) for stereoscopic viewing. Stereoscopic assessments gave higher CDRs in temporal, superior, nasal, and inferior aspects of the optic disc (p<0.001, Mann-Whitney U test). Agreement between observers in estimating CDR was high for monoscopic assessment (intraclass correlation coefficient 0.74 (CI 0.72 to 0.76) increasing to 0.80 (0.78 to 0.82) for stereoscopic assessment.

CONCLUSION

Digital stereoscopic optic disc assessment provides lower estimates of neuroretinal rim width and higher levels of interobserver agreement compared with monoscopic assessments.

Ocular complications of neurological therapy

Treatments used for several neurological conditions may adversely affect the eye. Vigabatrin-related retinal toxicity leads to a visual field defect. Optic neuropathy may result from ethambutol and isoniazid, and from radiation therapy. Posterior subcapsular cataract is associated with systemic corticosteroids. Transient refractive error changes may follow treatment with acetazolamide or topiramate, and corneal deposits and keratitis with amandatine. Intraocular pressure can be elevated in susceptible individuals by anticholinergic drugs, including oxybutynin, tolterodine, benzhexol, propantheline, atropine and amitriptyline, and also by systemic corticosteroids and by topiramate. Nystagmus, diplopia and extraocular muscle palsies can occur with antiepileptic drugs, particularly phenytoin and carbamazepine. Ocular neuromyotonia can follow parasellar radiation. Congenital ocular malformations can result from in utero exposure to maternally prescribed sodium valproate, phenytoin and carbamazepine. Neurologists must be aware of potential ocular toxicity of these drugs, and appropriately monitor for potential adverse events.

Evaluation of the high specificity Screening Program (C-20-1) of the Frequency Doubling Technology (FDT) perimeter in clinical practice

AIMS

To compare the efficacy of the high specificity Frequency Doubling Technology (FDT) Perimeter Screening Program (C-20-1) to standard threshold automated perimetry in the diagnosis of open-angle glaucoma.

METHODS

A total of 100 consecutively presenting patients attending a glaucoma clinic who volunteered for the study (approximately 30% of whom were attending for an initial visit) were examined with the FDT C-20-1 Screening Program and with the Humphrey Field Analyzer (HFA) SITA Fast algorithm and Program 24-2.

RESULTS

Of the patients, 17 were excluded due to unreliable visual field results or non-glaucomatous ocular abnormalities. In all, 10 patients were diagnosed as normal, 54 with open-angle glaucoma, eight with ocular hypertension, and 11 as glaucoma suspects. Of the 54 glaucomatous patients, 45 exhibited high-tension glaucoma and nine normal tension glaucoma. Perimetry with the HFA gave a sensitivity of 81.5% for the combined category of glaucoma and glaucoma suspect and a specificity of 83.3% for the combined category of normal and ocular hypertension. Perimetry with the FDT gave a sensitivity of 74.5% and a specificity of 85.2% compared to that of the HFA.

CONCLUSION

In the detection of glaucoma, Program C-20-1 of the FDT perimeter exhibits high specificity. It exhibits low sensitivity for the detection of mild loss but high sensitivity for advanced field loss relative to Program 24-2 and the SITA Fast algorithm of the HFA.

Discrimination of glaucomatous optic neuropathy by digital stereoscopic analysis

PURPOSE

To evaluate the diagnostic power of a novel digital stereoscopic imaging system in the diagnosis of glaucomatous optic neuropathy.

DESIGN

Prospective cross-sectional analysis of the diagnostic accuracy of digital stereoscopic optic disc analysis in the diagnosis of glaucomatous optic neuropathy exhibiting mild to moderate field loss.

PARTICIPANTS

Fifty-two patients with open-angle glaucoma and 54 normal individuals were recruited. The presence of a reproducible visual field loss characteristic of glaucoma was used as the reference standard for the presence of glaucoma independent of the optic nerve head appearance. Patients were excluded if the optic disc, fundus, or visual field indicated other disease. One eye from each patient and individual was included in the study, the eye with the least field loss and a randomly designated normal eye, respectively.

METHODS

Simultaneous stereoscopic optic disc photography was performed on each specified eye. Three experienced observers viewed the resultant stereoscopic image of each nerve head using a Z screen, recorded a subjective clinical diagnosis, and undertook digital stereoscopic planimetry. Separate linear regression analysis was performed, post hoc, from the planimetric results for each observer of the logarithm of neuroretinal rim (NRR) against optic disc area derived from each normal eye. Eyes with NRR areas below the 95th prediction interval of the normal cohort were then classified as glaucomatous.

MAIN OUTCOME MEASURES

Sensitivity and specificity for the detection of glaucomatous optic neuropathy.

RESULTS

With subjective stereoscopic analysis, sensitivity for glaucoma detection among the 3 observers was 80.8%, 76.9%, and 90.4%, with respective specificities of 94.4%, 79.6%, and 79.6%. Regression analysis of the NRR in 30 degrees segments gave sensitivities between 69.2% and 80.8% and specificities between 83.3% and 90.7%. A combination of the subjective and quantitative analysis did not significantly improve discrimination.

CONCLUSIONS

The subjective analysis of digital stereoscopic images provides a useful method for the discrimination of normal and glaucomatous optic nerves. Planimetric analysis does not significantly improve the diagnostic precision of this technique.

Human muscle precursor cell regeneration in the mouse host is enhanced by growth factors

The aim of this study was to optimize human muscle formation in vivo from implanted human muscle precursor cells. We transplanted donor muscle precursor cells (MPCs) prepared from postnatal or fetal human muscle into immunodeficient host mice and showed that irradiation of host muscle significantly enhanced muscle formation by donor cells. The amount of donor muscle formed in cryodamaged host muscle was increased by exposure of donor cells to growth factors before their implantation into injured host muscle. Insulin-like growth factor type I (IGF-I) significantly increased the amount of muscle formed by postnatal human muscle cells, but not by fetal human MPCs. However, treatment of fetal muscle cells with IGF-I, in combination with basic fibroblast growth factor and plasmin, significantly increased the amount of donor muscle formed. In vivo, human MPCs formed mosaic human-mouse muscle fibers, in which each human myonucleus was associated with a zone of human sarcolemmal protein spectrin.

Circulation and axonal transport in the optic nerve

Retinal ganglion cells are the output cells of the retina whose axons are under considerable metabolic stress in both health and disease states. They are highly polarised to ensure that mitochondria and enzymes involved in the generation of ATP are strategically concentrated to meet the local energy demands of the cell. In passing from the eye to the brain, axons are protected and supported by glial tissues and the blood supply of the optic nerve head is regulated to maintain the supply of oxygen and nutrients to the axons. In spite of this, the optic nerve head remains the point at which retinal ganglion cell axons are most vulnerable to the effects of increased intraocular pressure or ischaemia. Considerable work has been undertaken in this area to advance our understanding on the pathophysiology of axon damage and to develop new strategies for the prevention of retinal ganglion cell death.

Advances in broad bandwidth light sources for ultrahigh resolution optical coherence tomography

Novel ultra-broad bandwidth light sources enabling unprecedented sub-2 microm axial resolution over the 400 nm-1700 nm wavelength range have been developed and evaluated with respect to their feasibility for clinical ultrahigh resolution optical coherence tomography (UHR OCT) applications. The state-of-the-art light sources described here include a compact Kerr lens mode locked Ti:sapphire laser (lambdaC = 785 nm, delta lambda = 260 nm, P(out) = 50 mW) and different nonlinear fibre-based light sources with spectral bandwidths (at full width at half maximum) up to 350 nm at lambdaC = 1130 nm and 470 nm at lambdaC = 1375 nm. In vitro UHR OCT imaging is demonstrated at multiple wavelengths in human cancer cells, animal ganglion cells as well as in neuropathologic and ophthalmic biopsies in order to compare and optimize UHR OCT image contrast, resolution and penetration depth.

Histological measurement of retinal nerve fibre layer thickness

PURPOSE

Accurate assessment of the retinal nerve fibre layer (RNFL) is central to the diagnosis and follow-up of glaucoma. The in vivo measurement of RNFL thickness by a variety of digital imaging technologies is becoming an important measure for early detection, as well as for follow-up, of glaucomatous damage. However, when drawing clinical inference concerning the state of the RNFL, it is important to have valid reference data on RNFL thickness in both healthy and diseased eyes. In this review, we summarize the knowledge currently available about RNFL thickness in human and primate eyes.

METHODS

A review of the literature on histological analysis of RNFL thickness in the context of glaucomatous damage.

CONCLUSIONS

Six studies have so far analysed RNFL thickness. Despite the diverse study methodology taken, a consistent feature of all the data is that the superior and inferior quadrants of the peripapillary retina are thicker than the nasal and temporal quadrants; that the RNFL thickness rapidly diminishes with increasing distance from the disc margin; and that apparently at different locations the ratio of axons to supportive tissue varies significantly. We conclude that limited data are available to describe the normal variation in RNFL thickness in the normal human eye. Further studies may help better characterize the RNFL thickness in health and disease and to facilitate the correlation with clinical methods for nerve fibre layer assessment.