A RCT to explore the effectiveness of supporting adherence to nebuliser medication in adults with cystic fibrosis: fidelity assessment of study interventions

BACKGROUND

A multi-component self-management intervention 'CFHealthHub' was developed to reduce pulmonary exacerbations in adults with Cystic Fibrosis (CF) by supporting adherence to nebuliser medication. It was evaluated in a randomized controlled trial (RCT) involving 19 CF centres, with 32 interventionists, 305 participants in the intervention group, and 303 participants in the standard care arm. Ensuring treatment fidelity of intervention delivery was crucial to ensure that the intervention produced the expected outcomes.

METHODS

Fidelity of the CFHealthHub intervention and standard care was assessed using different methods for each of the five fidelity domains defined by the Borrelli framework: study design, training, treatment delivery, receipt, and enactment. Study design ensured that the groups received the intended intervention or standard care. Interventionists underwent training and competency assessments to be deemed certified to deliver the intervention. Audio-recorded intervention sessions were assessed for fidelity drift. Receipt was assessed by identifying whether participants set Action and Coping Plans, while enactment was assessed using click analytics on the CFHealthHub digital platform.

RESULTS

Design: There was reasonable agreement (74%, 226/305) between the expected versus actual intervention dose received by participants in the CFHealthHub intervention group. The standard care group did not include focused adherence support for most centres and participants. Training: All interventionists were trained. Treatment delivery: The trial demonstrated good fidelity (overall fidelity by centre ranged from 79 to 97%), with only one centre falling below the mean threshold (> 80%) on fidelity drift assessments. Receipt: Among participants who completed the 12-month intervention, 77% (205/265) completed at least one action plan, and 60% (160/265) completed at least one coping plan. Enactment: 88% (268/305) of participants used web/app click analytics outside the intervention sessions. The mean (SD) number of web/app click analytics per participant was 31.2 (58.9). Additionally, 64% (195/305) of participants agreed to receive notifications via the mobile application, with an average of 53.6 (14.9) notifications per participant.

CONCLUSIONS

The study demonstrates high fidelity throughout the RCT, and the CFHealthHub intervention was delivered as intended. This provides confidence that the results of the RCT are a valid reflection of the effectiveness of the CFHealthHub intervention compared to standard care.

TRIAL REGISTRATION

ISRCTN registry: ISRCTN55504164 (date of registration: 12/10/2017).

Full automation of total metabolic tumor volume from FDG-PET/CT in DLBCL for baseline risk assessments

Background

Current radiological assessments of ¹⁸fluorodeoxyglucose-positron emission tomography (FDG-PET) imaging data in diffuse large B-cell lymphoma (DLBCL) can be time consuming, do not yield real-time information regarding disease burden and organ involvement, and hinder the use of FDG-PET to potentially limit the reliance on invasive procedures (e.g. bone marrow biopsy) for risk assessment.

Methods

Our aim is to enable real-time assessment of imaging-based risk factors at a large scale and we propose a fully automatic artificial intelligence (AI)-based tool to rapidly extract FDG-PET imaging metrics in DLBCL. On availability of a scan, in combination with clinical data, our approach generates clinically informative risk scores with minimal resource requirements. Overall, 1268 patients with previously untreated DLBCL from the phase III GOYA trial (NCT01287741) were included in the analysis (training: n = 846; hold-out: n = 422).

Results

Our AI-based model comprising imaging and clinical variables yielded a tangible prognostic improvement compared to clinical models without imaging metrics. We observed a risk increase for progression-free survival (PFS) with hazard ratios [HR] of 1.87 (95% CI: 1.31–2.67) vs 1.38 (95% CI: 0.98–1.96) (C-index: 0.59 vs 0.55), and a risk increase for overall survival (OS) (HR: 2.16 (95% CI: 1.37–3.40) vs 1.40 (95% CI: 0.90–2.17); C-index: 0.59 vs 0.55). The combined model defined a high-risk population with 35% and 42% increased odds of a 4-year PFS and OS event, respectively, versus the International Prognostic Index components alone. The method also identified a subpopulation with a 2-year Central Nervous System (CNS)-relapse probability of 17.1%.

Conclusion

Our tool enables an enhanced risk stratification compared with IPI, and the results indicate that imaging can be used to improve the prediction of central nervous system relapse in DLBCL. These findings support integration of clinically informative AI-generated imaging metrics into clinical workflows to improve identification of high-risk DLBCL patients.

Trial Registration

Registered clinicaltrials.gov number: NCT01287741.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s40644-022-00476-0.

Development of an intervention to increase adherence to nebuliser treatment in adults with cystic fibrosis: CFHealthHub

BACKGROUND

Cystic fibrosis (CF) is a life-limiting genetic condition in which daily therapies to maintain lung health are critical, yet treatment adherence is low. Previous interventions to increase adherence have been largely unsuccessful and this is likely due to a lack of focus on behavioural evidence and theory alongside input from people with CF. This intervention is based on a digital platform that collects and displays objective nebuliser adherence data. The purpose of this paper is to identify the specific components of an intervention to increase and maintain adherence to nebuliser treatments in adults with CF with a focus on reducing effort and treatment burden.

METHODS

Intervention development was informed by the Behaviour Change Wheel (BCW) and person-based approach (PBA). A multidisciplinary team conducted qualitative research to inform a needs analysis, selected, and refined intervention components and methods of delivery, mapped adherence-related barriers and facilitators, associated intervention functions and behaviour change techniques, and utilised iterative feedback to develop and refine content and processes.

RESULTS

Results indicated that people with CF need to understand their treatment, be able to monitor adherence, have treatment goals and feedback and confidence in their ability to adhere, have a treatment plan to develop habits for treatment, and be able to solve problems around treatment adherence. Behaviour change techniques were selected to address each of these needs and were incorporated into the digital intervention developed iteratively, alongside a manual and training for health professionals. Feedback from people with CF and clinicians helped to refine the intervention which could be tailored to individual patient needs.

CONCLUSIONS

The intervention development process is underpinned by a strong theoretical framework and evidence base and was developed by a multidisciplinary team with a range of skills and expertise integrated with substantial input from patients and clinicians. This multifaceted development strategy has ensured that the intervention is usable and acceptable to people with CF and clinicians, providing the best chance of success in supporting people with CF with different needs to increase and maintain their adherence. The intervention is being tested in a randomised controlled trial across 19 UK sites.

ESMO Consensus Conference on malignant lymphoma: management of 'ultra-high-risk' patients

The European Society for Medical Oncology (ESMO) consensus conference on malignant lymphoma was held on 20 June 2015 in Lugano, Switzerland, and included a multidisciplinary panel of 25 leading experts. The aim of the conference was to develop recommendations on critical subjects difficult to consider in detail in the ESMO Clinical Practice Guidelines. The following areas were identified: (1) the elderly patient, (2) prognostic factors suitable for clinical use and (3) the 'ultra-high-risk' group. Before the conference, the expert panel was divided into three working groups; each group focused on one of these areas in order to address clinically relevant questions relating to that topic. All relevant scientific literature, as identified by the experts, was reviewed in advance. During the consensus conference, each working group developed recommendations to address each of the questions devised by their group. These recommendations were then presented to the entire multidisciplinary panel and a consensus was reached. This manuscript presents recommendations regarding the management of the following 'ultra-high-risk' situations: (1) early central nervous system relapse of diffuse large B-cell lymphoma, (2) primary refractory Hodgkin lymphoma and (3) plasmablastic lymphoma. Results, including a summary of evidence supporting each recommendation, are detailed in this manuscript. All expert panel members approved this final article.

ESMO Consensus Conference on malignant lymphoma: general perspectives and recommendations for the clinical management of the elderly patient with malignant lymphoma

The European Society for Medical Oncology (ESMO) consensus conference on mature B cell lymphomas and chronic lymphocytic leukaemia (CLL) was held on 20 June 2015 in Lugano, Switzerland, and included a multidisciplinary panel of 25 leading experts. The aim of the conference was to develop recommendations on critical subjects difficult to consider in detail in the ESMO Clinical Practice Guidelines. The following areas were identified: (1) the elderly patient, (2) prognostic factors suitable for clinical use, and (3) the 'ultra-high-risk' group. Before the conference, the expert panel was divided into three working groups; each group focused on one of these areas in order to address clinically-relevant questions relating to that topic. All relevant scientific literature, as identified by the experts, was reviewed in advance. During the consensus conference, each working group developed recommendations to address each of the four questions assigned to their group. These recommendations were presented to the entire panel and a consensus was reached. This consensus, which was further developed in continuous post-meeting discussions, formed the basis of three manuscripts, each covering one of the three key areas identified. This manuscript presents the consensus recommendations regarding the clinical management of elderly patients diagnosed with malignant lymphoma. Four clinically-relevant topics identified by the panel were: 1) how to define patient fitness, 2) assessing quality of life, 3) diagnostic work-up and 4) clinical management of elderly patients with lymphoma. Each of these key topics is addressed in the context of five different lymphoma entities, namely: CLL, follicular lymphoma, mantle cell lymphoma, peripheral T-cell lymphoma and diffuse large B-cell lymphoma. Results, including a summary of evidence supporting each recommendation, are detailed in this manuscript.

International Working Group consensus response evaluation criteria in lymphoma (RECIL 2017)

In recent years, the number of approved and investigational agents that can be safely administered for the treatment of lymphoma patients for a prolonged period of time has substantially increased. Many of these novel agents are evaluated in early-phase clinical trials in patients with a wide range of malignancies, including solid tumors and lymphoma. Furthermore, with the advances in genome sequencing, new "basket" clinical trial designs have emerged that select patients based on the presence of specific genetic alterations across different types of solid tumors and lymphoma. The standard response criteria currently in use for lymphoma are the Lugano Criteria which are based on [18F]2-fluoro-2-deoxy-D-glucose positron emission tomography or bidimensional tumor measurements on computerized tomography scans. These differ from the RECIST criteria used in solid tumors, which use unidimensional measurements. The RECIL group hypothesized that single-dimension measurement could be used to assess response to therapy in lymphoma patients, producing results similar to the standard criteria. We tested this hypothesis by analyzing 47 828 imaging measurements from 2983 individual adult and pediatric lymphoma patients enrolled on 10 multicenter clinical trials and developed new lymphoma response criteria (RECIL 2017). We demonstrate that assessment of tumor burden in lymphoma clinical trials can use the sum of longest diameters of a maximum of three target lesions. Furthermore, we introduced a new provisional category of a minor response. We also clarified response assessment in patients receiving novel immune therapy and targeted agents that generate unique imaging situations.

ESMO consensus conference on malignant lymphoma: general perspectives and recommendations for prognostic tools in mature B-cell lymphomas and chronic lymphocytic leukaemia

The European Society for Medical Oncology (ESMO) consensus conference on mature B-cell lymphomas and chronic lymphocytic leukaemia (CLL) was held on 20 June 2015 in Lugano, Switzerland, and included a multidisciplinary panel of 25 leading experts. The aim of the conference was to develop recommendations on critical subjects difficult to consider in detail in the ESMO Clinical Practice Guidelines. The following areas were identified: (i) the elderly patient, (ii) prognostic factors suitable for clinical use and (iii) the 'ultra-high-risk' group. Before the conference, the expert panel was divided into three working groups; each group focused on one of these areas in order to address four clinically relevant questions relating to that topic. All relevant scientific literature, as identified by the experts, was reviewed in advance. During the consensus conference, each working group developed recommendations to address each of the four questions assigned to their group. These recommendations were then presented to the entire panel and a consensus was reached. This manuscript presents recommendations dedicated to the second area of interest, i.e. prognostic factors suitable for clinical use. The four topics [i.e. interim positron emission tomography (PET), TP53 mutations, cell of origin (COO) and minimal residual disease (MRD)] were primarily chosen because of the bulk of available data together with the lack of clear guidance regarding their use in clinical practice and within clinical trials. Results, including a summary of evidence supporting each recommendation, are detailed in this manuscript. The panel acknowledged that detection of TP53 inactivation by deletion or mutation in CLL should be implemented in clinical practice (level of evidence I, strength of recommendation A). Due to their potentially high prognostic value, at least in some lymphoma entities, implementation of interim PET, COO and MRD was highly recommended in the context of clinical trials. All expert panel members approved this final article.

The value of routine bone marrow biopsy in patients with diffuse large B-cell lymphoma staged with PET/CT: a Danish-Canadian study

BACKGROUND

The added diagnostic and prognostic value of routine bone marrow biopsy (BMB) in patients with diffuse large B-cell lymphoma (DLBCL) undergoing positron emission tomography combined with computed tomography (PET/CT) staging is controversial.

PATIENTS AND METHODS

Patients with newly diagnosed DLBCL who underwent both staging PET/CT and BMB were retrospectively identified in British Columbia, Aalborg, and Copenhagen. Original written PET/CT and pathology reports were retrospectively reviewed to determine Ann Arbor stage and outcomes, with and without the contribution of BMB.

RESULTS

A total of 530 patients were identified: 146 (28%) had focal bone marrow (BM) lesions on PET/CT and 87 (16%) had positive BMB. Fifty-two of 146 patients (36%) with positive PET/CT had a positive BMB [39 DLBCL, 13 indolent non-Hodgkin lymphoma (iNHL)], while 35 of 384 patients (9%) with negative PET/CT had positive BMB (12 DLBCL, 23 iNHL). BMB upstaged 12/209 (6%) of stage I/II patients to stage IV, although this was the case for only 3 (1%) patients with DLBCL in the BMB. PET/CT identified BM involvement by BMB with sensitivity 60%, specificity 79%, positive predictive value 36%, and negative predictive value 91%. Concordant histological involvement of the BM by DLBCL was associated with worse overall survival and progression-free survival than discordant or no involvement in univariate and multivariate analyses.

CONCLUSIONS

In patients with DLBCL, staging PET/CT can miss BM involvement with concordant DLBCL (less common) or discordant iNHL (more common). Routine BMB does not add relevant diagnostic or prognostic value over PET/CT alone in the majority of patients with DLBCL.

FDG-PET after two to three cycles of chemotherapy predicts progression-free and overall survival in high-grade non-Hodgkin lymphoma

BACKGROUND

Less than 50% of all high-grade non-Hodgkin lymphoma (NHL) patients experience lasting disease-free survival. Risk-adapted treatment strategies require better tools for prediction of outcome. This investigation aimed to assess the value of positron emission tomography with 2-[18F]fluoro-2-deoxy-D-glucose (FDG-PET) after two to three cycles of chemotherapy for prediction of progression-free survival (PFS) and overall survival (OS).

PATIENTS AND METHODS

One hundred and twenty-one patients with high-grade NHL underwent FDG-PET. The therapy response on FDG-PET was correlated to PFS and OS using Kaplan-Meier survival analysis. Cox regression analyses were employed to test for independence of known pretreatment prognostic factors.

RESULTS

Fifty FDG-PET scans were negative, 19 scans showed minimal residual uptake (MRU), and 52 scans were positive. The estimated 5 year PFS was 88.8% for the PET-negative group, 59.3% for the MRU group, and 16.2% for the PET-positive group. Kaplan-Meier analyses showed strong associations between FDG-PET results and PFS (P <0.0001) and OS (P <0.01). Early interim FDG-PET was independent of the other prognostic factors.

CONCLUSIONS

Early interim FDG-PET is an accurate and independent predictor of PFS and OS. An early assessment of chemotherapy response with FDG-PET could provide the basis for selection of patients for alternative therapeutic strategies.

Prognostic value of interim FDG-PET after two or three cycles of chemotherapy in Hodgkin lymphoma

BACKGROUND

Long-term survival from Hodgkin lymphoma (HL) is 80-90%, but the treatment has serious late adverse effects. Modern risk-adapted treatment requires accurate assessment of the patient's prognosis. This investigation assessed the value of positron emission tomography (PET) with 2-[18F]fluoro-2-deoxy-D-glucose (FDG-PET) after two or three cycles of chemotherapy for prediction of progression-free survival (PFS) and overall survival (OS).

PATIENTS AND METHODS

A total of 85 patients with HL underwent FDG-PET after two or three cycles of chemotherapy. Median follow-up was 3.3 years. FDG-PET results were related to PFS and OS using Kaplan-Meier analysis. Regression analyses were employed to test for independence of established pretreatment prognostic factors.

RESULTS

After two or three cycles of chemotherapy, 63 patients had negative FDG-PET scans, nine patients had minimal residual uptake (MRU) and 13 patients had positive scans. Three PET-negative patients and one patient from the MRU group relapsed. In the PET-positive group, nine patients progressed and two died. Survival analyses showed highly significant associations between early interim FDG-PET and PFS (P <0.0001) and OS (P <0.03). All advanced-stage patients with positive interim FDG-PET relapsed within 2 years.

CONCLUSION

Early interim FDG-PET is an accurate and independent predictor of PFS and OS in HL. A positive interim FDG-PET is highly predictive of relapse in advanced-stage disease.

Renal 131I-hippuran extraction in man: effects of dopamine

AIMS

This study examined the 131I-hippuran extraction fraction during baseline renal blood flow rates and at high flow rates induced by dopamine.

METHODS

In 12 healthy subjects, arterial and renal venous sampling was used to measure the renal extraction of 131I-hippuran. Effective renal plasma flow values determined by the urinary clearance of 131I-hippuran were compared with renal plasma flow values corrected for incomplete extraction of 131I-hippuran.

RESULTS

Dopamine (3 micro g kg-1 min-1) decreased 131I-hippuran extraction from 75 +/- 4% at baseline to 62 +/- 6% (means +/- 95% confidence intervals, P < 0.001). Hence, the increase in renal plasma flow (85 +/- 23%) greatly exceeded the rise in effective renal plasma flow (51 +/- 15%, P < 0.002).

CONCLUSIONS

Dopamine induced increases in renal blood flow are largely under-estimated when measurements are not corrected for incomplete extraction of 131I-hippuran.

4-Pyridin-5-yl-2-(3,4,5-trimethoxyphenylamino)pyrimidines: potent and selective inhibitors of ZAP 70

Activation of the tyrosine kinase ZAP 70 has been shown to be crucial to the transduction of the T-cell receptor signalling pathway, which leads ultimately to proliferation, cytokine gene expression and T-cell effector functions. A series of 2-phenylaminopyrimidines have been identified as potent and selective inhibitors of ZAP 70.

Treatment with granulocyte colony-stimulating factor decreases the capacity of hematopoietic progenitor cells for generation of lymphocytes in human immunodeficiency virus-infected persons

An obstacle to stem cell gene therapy for AIDS is the limited numbers of hematopoietic progenitors available. Granulocyte colony-stimulating factor (G-CSF) is used for mobilization of progenitors, but little is known about the functional characteristics of mobilized progenitors, and immature and T cell progenitors may not be mobilized. This study examined the effect of G-CSF on the function of progenitors. Ten human immunodeficiency virus-infected patients received G-CSF (filgrastim, 300 microgram/day) for 5 days. Absolute numbers of immature and T cell progenitors did not increase. The ability of CD34+ progenitor cells to generate lymphocytes was examined by use of thymic organ cultures. The mean number of lymphocytes generated per CD34+ cell on day 0 was 0.72 and on day 4 was 0.09 (P<.003). The number of CD4+ cells generated per CD34+ cell was significantly reduced after G-CSF treatment. Thus, G-CSF increased the number of mature progenitor cells but did not increase T cell progenitors.

Selective loss of progenitor subsets following clinical CD34+ cell enrichment by magnetic field, magnetic beads or chromatography separation

In this preclinical evaluation we have compared the efficacy of three clinical CD34+enrichment procedures with respect to purity, yield and recovery, as well as risk of selective loss of CD34+ lineage-specific subsets. The three devices work by different principles and have several different manipulation steps: The magnetic field separator uses paramagnetic iron-dextran particles; the magnetic microbead selection is based on the advantage of a large surface area for immobilisation of the monoclonal antibody within a very small volume; the original immunoabsorption technique is based on the use of biotinylated antibody applied to a column of avidin-coated sephadex beads. The results of this evaluation gave a median purity 96% (88-98%), 86% (62-97%), and 49% (18-85%), and median yield of 65% (54-100%), 40% (21-74%), and 30% (8-55%), respectively. Subset analysis recognised a selective loss of CD34+/61+ after enrichment, most likely due to class I-II antibodies used for the enrichment step or, alternatively, nonspecific binding of megakaryocytic progenitors. Tumour cell spiking experiments on a clinical scale documented an expected 2-4 log reduction resulting in a number of potentially malignant cells in the CD34 enriched product. Our data support four major conclusions: First, that magnetic field separation is superior to magnetic beads and chromatography selection, mainly due to the risk of cell loss and insufficient recovery with the two latter methods. Second, that late differentiated progenitors with CD34 class III epitopes present are lost during the enrichment procedures. The third major conclusion is that chromatography selection results in a selective loss of CD34bright cells, which are most likely uncommitted early progenitors. This was an unexpected finding which may be a consequence of an imbalance between the strong forces between biotin-avidin and insufficient physical manipulation for CD34+ cell release. Finally, the data document that CD34 selection alone is an inappropriate way to eliminate tumour cells due to the uncontrolled variables and the inconsistent outcome. The only products which can be expected to be purged free of tumour cells are the ones with very minimal (<10-5) contamination in the starting products, ie products documented tumour free with the most sensitive techniques for quantitation. If this is not the case, the optimal purging strategy may be a two-step procedure including CD34 selection and subsequent depletion of the tumour cells in question.

Cerebral amyloid angiopathy: amyloid beta accumulates in putative interstitial fluid drainage pathways in Alzheimer's disease

Cerebral amyloid angiopathy in Alzheimer's disease is characterized by deposition of amyloid beta (Abeta) in cortical and leptomeningeal vessel walls. Although it has been suggested that Abeta is derived from vascular smooth muscle, deposition of Abeta is not seen in larger cerebral vessel walls nor in extracranial vessels. In the present study, we examine evidence for the hypothesis that Abeta is deposited in periarterial interstitial fluid drainage pathways of the brain in Alzheimer's disease and that this contributes significantly to cerebral amyloid angiopathy. There is firm evidence in animals for drainage of interstitial fluid from the brain to cervical lymph nodes along periarterial spaces; similar periarterial channels exist in humans. Biochemical study of 6 brains without Alzheimer's disease revealed a pool of soluble Abeta in the cortex. Histology and immunocytochemistry of 17 brains with Alzheimer's disease showed that Abeta accumulates five times more frequently around arteries than around veins, with selective involvement of smaller arteries. Initial deposits of Abeta occur at the periphery of arteries at the site of the putative interstitial fluid drainage pathways. These observations support the hypothesis that Abeta is deposited in periarterial interstitial fluid drainage pathways of the brain and contributes significantly to cerebral amyloid angiopathy in Alzheimer's disease.

Increased transduction efficiency of primary hematopoietic cells by physical colocalization of retrovirus and target cells

Efficient gene transfer into hematopoietic stem cells offers a number of potential therapeutic applications. However, the relatively low titer of retroviral supernatants and the requirement for cell division to ensure integration have meant that transduction efficiency has been low. We have modified a flowthrough approach to cell transduction and have been able consistently to increase gene transfer efficiency into human hematopoietic progenitor cells. We transduced CD34 cells with retroviral vectors encoding a truncated nerve growth factor receptor (NGFR) or neo. Retroviral supernatant was pulled through 0.2-micron polycarbonated membranes, followed by placement of cells on the filter. In the absence of cytokines, the transduction efficiency of CD34 cells with a NGFR vector was increased 3-11-fold over that obtained at an identical MOI in liquid culture to produce 11%-44% transduction. Furthermore, both Thy1+ and Thy1- subsets in a total CD34 population were transduced with similar efficiency, and transduction with a neo vector, as measured by G418 resistance in clonogenic assays, increased 1.5-5-fold. The mechanism by which gene transfer is improved may reflect colocalization of cells and retrovirus. Costaining of cells transduced on the filter with an NGFR retrovirus with both an NGFR antibody and a gp70 antibody that recognizes viral coat protein revealed high-level coexpression. The levels of in vitro gene transfer we obtain are equivalent to those observed when CD34 cells are cocultured in liquid culture with cytokines. However, culture with cytokines may commit CD34 cells to differentiation and has produced disappointingly low levels of subsequent in vivo gene transfer. Gene marking studies using distinguishable retroviral vectors will provide a means of learning whether the effects of flowthrough transduction genuinely enhance the efficiency of gene transfer to human marrow-repopulating cells.

Perivascular spaces in the basal ganglia of the human brain: their relationship to lacunes

There is evidence for lymphatic drainage of interstitial fluid from the brain along perivascular spaces in a number of mammalian species. Ultrastructural studies suggest that there are similar drainage pathways in the human cerebral cortex. Perivascular spaces in the basal ganglia, however, differ from those in the cortex in that they dilate to form lacunes and rarely accumulate beta-amyloid (amyloid angiopathy) in Alzheimer's disease; in the cortex, lacunes are rare but amyloid angiopathy is common. The aim of the present study is to compare the structure of perivascular spaces in the basal ganglia and at the anterior perforated substance with perivascular spaces in the cerebral cortex. Eight postmortem brains from patients aged 23-80 years (mean 68 y) were examined by light microscopy, by scanning and transmission electron microscopy and by direct visualisation of etched paraffin blocks. The results show that arteries in the basal ganglia are surrounded by 2 distinct coats of leptomeninges separated by a perivascular space which is continuous with the perivascular space around arteries in the subarachnoid space. The inner layer of leptomeninges closely invests the adventitia of the vessel wall and the outer layer is continuous with the pia mater on the surface of the brain at the anterior perforated substance. Veins in the basal ganglia have no outer layer of leptomeninges and thus the perivascular space is continuous with the subpial space. The anatomy of the periarterial spaces in the basal ganglia differs significantly from that in the cerebral cortex where there is only a single periarterial layer of leptomeninges. Differences in structure of perivascular spaces around arteries may reflect relative efficiencies in the drainage of interstitial fluid from different sites in the brain. Furthermore, the structure of the perivascular spaces may contribute to the relatively high frequency of lacunes in the basal ganglia, and the low frequency of amyloid angiopathy at this site in Alzheimer's disease.

Acquired high titre factor VIII inhibitor with underlying polyarteritis nodosa

We here present the case of a 70-year-old woman referred to our unit for investigation of bleeding. Investigations confirmed a high titre acquired Factor VIII inhibitor. In association there was relapse of systemic illness associated with anti-neutrophil cytoplasmic antibodies (atypical pattern) for which she had been treated five years previously. Immunosuppression was attempted, but it failed to have an impact both on the inhibitor titre and on the underlying disorder. The patient died from multi-organ failure and massive chest hemorrhage. Post-mortem showed necrotizing vasculitis of medium sized vessels at several sites, including the kidney, consistent with a diagnosis of polyarteritis nodosa. Although it is well recognised that Factor VIII inhibitors are found in conjunction with autoimmune disorders, this case is significant in that it is the first associated with histologically proven polyarteritis nodosa type vasculitis. The case illustrates the difficulties in the investigation and management of patients with acquired high titre Factor VIII inhibitors.

Posterior fontanelle cranial ultrasound: anatomic and sonographic correlation

OBJECTIVE

The purpose of this study was to correlate normal brain anatomy as seen on posterior fontanelle cranial sonography with anatomical sections of the premature infant brain.

MATERIALS AND METHODS

Images obtained from 93 cranial ultrasound examinations performed via both the anterior and posterior fontanelle in 53 infants, ranging in gestational age from 24 to 42 weeks, were reviewed to determine the ultrasound anatomy visible and also the changing appearances with increasing gestational age. The brains of five infants were sectioned at post-mortem according to predetermined anatomical landmarks to correlate with posterior fontanelle ultrasound scan planes. Brain preservation techniques involved fixation in formalin at room temperature, refrigeration of brain following formalin fixation, and brain freezing at -17 degrees C.

RESULTS

In the premature infant brain, the subarachnoid space is up to 15 mm in thickness. Occipital lobe anatomy well seen includes occipital horns of lateral ventricles, and white matter tracts to the visual cortex and visual association areas. Brain anatomy was better appreciated on sections obtained following brain freezing rather than formalin fixation.

CONCLUSION

Satisfactory ultrasound anatomic correlation of the premature brain is possible using a brain freezing preservation technique. Posterior fontanelle ultrasound allows detailed illustration of occipital lobe anatomy.

Flexible approach to amperometric oxygen determination

In vitro and in vivo results obtained from a novel flexible amperometric oxygen sensor are reported. The sensor is fabricated using thin film deposition techniques and is operated by the application of a pulsed waveform. Development of the sensor was undertaken in order to produce a device that is capable of being sited at the interface of a wound and an overlying wound dressing. Oxygen determinations in such an environment would aid in gaining an understanding of the role of oxygen in wound healing and the type of wound dressing that would provide an environment conducive towards wound healing. In vitro data indicate that linearity of response is good although other performance characteristics are irreproducible. In vivo response to oxygen has been observed 50 h after insertion into a porcine sham wound. Expected trends were followed when changes to the oxygen regime of the wound space were effected, but absolute values of oxygen tension are difficult to state with certainty. This may be due to poor calibration stability and inadequate sealing of the sensor from the surrounding environment.