Advanced quantitative evaluation of PET systems using the ACR phantom and NiftyPET software

PURPOSE

A novel phantom-imaging platform, a set of software tools, for automated and high-precision imaging of the American College of Radiology (ACR) positron emission tomography (PET) phantom for PET/magnetic resonance (PET/MR) and PET/computed tomography (PET/CT) systems is proposed.

METHODS

The key feature of this platform is the vector graphics design that facilitates the automated measurement of the knife-edge response function and hence image resolution, using composite volume of interest templates in a 0.5 mm resolution grid applied to all inserts of the phantom. Furthermore, the proposed platform enables the generation of an accurate μ $\mu$ -map for PET/MR systems with a robust alignment based on two-stage image registration using specifically designed PET templates. The proposed platform is based on the open-source NiftyPET software package used to generate multiple list-mode data bootstrap realizations and image reconstructions to determine the precision of the two-stage registration and any image-derived statistics. For all the analyses, iterative image reconstruction was employed with and without modeled shift-invariant point spread function and with varying iterations of the ordered subsets expectation maximization (OSEM) algorithm. The impact of the activity outside the field of view (FOV) was assessed using two acquisitions of 30 min each, with and without the activity outside the FOV.

RESULTS

The utility of the platform has been demonstrated by providing a standard and an advanced phantom analysis including the estimation of spatial resolution using all cylindrical inserts. In the imaging planes close to the edge of the axial FOV, we observed deterioration in the quantitative accuracy, reduced resolution (FWHM increased by 1-2 mm), reduced contrast, and background uniformity due to the activity outside the FOV. Although it slows convergence, the PSF reconstruction had a positive impact on resolution and contrast recovery, but the degree of improvement depended on the regions. The uncertainty analysis based on bootstrap resampling of raw PET data indicated high precision of the two-stage registration.

CONCLUSIONS

We demonstrated that phantom imaging using the proposed methodology with the metric of spatial resolution and multiple bootstrap realizations may be helpful in more accurate evaluation of PET systems as well as in facilitating fine tuning for optimal imaging parameters in PET/MR and PET/CT clinical research studies.

Sustaining quality in the community: trends in the performance of a structured diabetes care programme in primary care over 16 years

AIM

To examine the quality of care delivered by a structured primary care-led programme for people with Type 2 diabetes mellitus in 1999-2016.

METHODS

The Midland Diabetes Structured Care Programme provides structured primary care-led management. Trends over time in care processes were examined (using a chi-squared trend test and age- and gender-adjusted logistic regression). Screening and annual review attendance were reviewed. A composite of eight National Institute for Health and Care Excellence-recommended processes was used as a quality indicator. Participants who were referred to diabetes nurse specialists were compared with those not referred (Student's t-test, Pearson's chi-squared test, Wilcoxon-Mann-Whitney test). Proportions achieving outcome targets [HbA_1c ≤58 mmol/mol (7.5%), blood pressure ≤140/80 mmHg, cholesterol <5.0 mmol/l] were calculated.

RESULTS

Data were available for people with diabetes aged ≥18 years: 1998/1999 (n=336); 2003 (n=843); 2008 (n=988); and 2016 (n=1029). Recording of some processes improved significantly over time (HbA_1c , cholesterol, blood pressure, creatinine), and in 2016 exceeded 97%. Foot assessment and annual review attendance declined. In 2016, only 29% of participants had all eight National Institute for Health and Care Excellence processes recorded. A higher proportion of people with diabetes who were referred to a diabetes nurse specialist had poor glycaemic control compared with those not referred. The proportions meeting blood pressure and lipid targets increased over time.

CONCLUSIONS

Structured primary care led to improvements in the quality of care over time. Poorer recording of some processes, a decline in annual review attendance, and participants remaining at high risk suggest limits to what structured care alone can achieve. Engagement in continuous quality improvement to target other factors, including attendance and self-management, may deliver further improvements.

Fancy a cup of scald? - The role of hot beverage burns in paediatric burns admissions in Ireland

Burns and scalds are preventable injuries in children that typically occur in the home. This study aimed to examine the role of hot beverage scalds in paediatric burn admissions in order to identify key target audiences for future safety strategies. Using the Hospital Inpatient Enquiry System (HIPE) a retrospective study of paediatric burn admissions in 2014 examined demographics, cause and severity of injury and location of occurrence. There were 233 paediatric discharges (age 0-18 yrs.) with a principal diagnosis of burn injury; 57% of these occurred in children under three years and 95% of these occurred in the home. Scalds caused 74% of burn injuries; hot beverages accounted for least 33% of these of which 77% were partial thickness and 73% were upper body burns. Effective hot beverage scald prevention strategies, targeted towards caregivers in the home, are required.

Opportunistic screening for atrial fibrillation in a rural area

INTRODUCTION

Opportunistic screening is an effective means of identifying subjects with Atrial Fibrillation (AF). Previous studies of opportunistic screening have been performed areas with high population density and before the development of novel oral anticoagulant drugs. We performed a study to determine feasibility of AF screening in a predominantly rural, low population density area.

METHODS

Over 6 months, subjects 65 years and older were screened by local General Practitioners using radial pulse palpation confirmed by 12 lead Electrocardiogram. Data were recorded electronically and those with newly identified AF were followed up to examine management post diagnosis.

RESULTS

In total, 7262 subjects were screened and an irregular pulse was found in 916 (12.6%) of whom 735 (10.1%) had known AF and 55 (0.76%) had newly detected AF. Of these 55 patients with newly documented AF, 28 (50.9%) were women, 38 (69.1%) had hypertension and eight (14.5%) had a smoking history. Mean body mass index in subjects with newly documented AF was 28.9 kg/m(2)(SD 5.6) There was no significant difference in gender mix (P =  0.4), smoking history (P  =  0.8) or alcohol history (P  =  0.8) with the overall population. Fifty-one (92.7%) subjects had a CHA2DS2VaSC score  ≥ 2 of whom 33 (64.7%) were eventually anticoagulated and nine (17.6%) commenced on Aspirin. The rate of newly identified patients in AF was lower than in previous reported key studies because of a higher rate of subjects with known AF.

CONCLUSION

Opportunistic AF screening in a rural environment identified a substantial number of new cases, although less than in previous screening studies.

Developing the radiation protection safety culture in the UK

In the UK, as elsewhere, there is potential to improve how radiological challenges are addressed through improvement in, or development of, a strong radiation protection (RP) safety culture. In preliminary work in the UK, two areas have been identified as having a strong influence on UK society: the healthcare and nuclear industry sectors. Each has specific challenges, but with many overlapping common factors. Other sectors will benefit from further consideration.In order to make meaningful comparisons between these two principal sectors, this paper is primarily concerned with cultural aspects of RP in the working environment and occupational exposures rather than patient doses.The healthcare sector delivers a large collective dose to patients each year, particularly for diagnostic purposes, which continues to increase. Although patient dose is not the focus, it must be recognised that collective patient dose is inevitably linked to collective occupational exposure, especially in interventional procedures.The nuclear industry faces major challenges as work moves from operations to decommissioning on many sites. This involves restarting work in the plants responsible for the much higher radiation doses of the 1960/70s, but also performing tasks that are considerably more difficult and hazardous than those original performed in these plants.Factors which influence RP safety culture in the workplace are examined, and proposals are considered for a series of actions that may lead to an improvement in RP culture with an associated reduction in dose in many work areas. These actions include methods to improve knowledge and awareness of radiation safety, plus ways to influence management and colleagues in the workplace. The exchange of knowledge about safety culture between the nuclear industry and medical areas may act to develop RP culture in both sectors, and have a wider impact in other sectors where exposures to ionising radiations can occur.

Breath metabolomic profiling by nuclear magnetic resonance spectroscopy in asthma

BACKGROUND

Metabolomic profiling of exhaled breath condensate offers opportunities for the development of noninvasive diagnostics in asthma. We aimed to determine and validate discriminatory metabolomic profiles in adult asthma and to explore profiles in clinically relevant disease phenotypes.

METHODS

Nuclear magnetic resonance spectroscopy was used to analyse breath condensate samples from 82 subjects with asthma and 35 healthy volunteers. Multivariate modelling was performed on a 'training set' (70% of the total sample) in order to produce a discriminatory model classifying asthmatics from healthy controls, and the model tested in the remaining subjects. Secondary analyses were performed to determine the models for the identification of asthmatic subgroups based on sputum eosinophilia, neutrophilia, asthma control and inhaled corticosteroid use.

RESULTS

A classification model consisting of five discriminating spectral regions was derived using data from the training set with an area under the receiver operating curve (AUROC) of 0.84. In the test set (the remaining 30% of subjects), the AUROC was 0.91, thus providing external validation for the model. The success of the technique for classifying asthma phenotypes was variable, with AUROC for: sputum eosinophilia (3% cut-off) 0.69; neutrophilia (65% cut-off) 0.88; asthma control (cut-off Asthma Control Questionnaire score of 1) 0.63; and inhaled corticosteroid use 0.89.

CONCLUSION

Nuclear magnetic resonance spectroscopy of breath condensate successfully differentiates asthmatics from healthy subjects. With identification of the discriminatory compounds, this technique has the potential to provide novel diagnostics and identify novel pathophysiological mechanisms, biomarkers and therapeutic targets.

Time from hospital admission to CT brain in acute ischaemic stroke

A retrospective study of all acute ischaemic stroke patients admitted to Midland Regional Hospital Mullingar (MRHM) between January 2004 and September 2009 was undertaken in order to assess the median time from hospital admission to CT brain scan (n = 496). The median time to CT scan ranged from 19-24 hours between 2004-7. In 2008, coinciding with setting up a new Acute Stroke Service (ACSS), the median time to CT scan dropped to 15 hours (n = 130, p =0.03) and decreased further to 3 hours in 2009 (n = 125, p = 0.003). The proportion scanned within 1 hour of admission increased from 7 patients (4.6%) over 2004-7, to 28 patients (21.5%) in 2008 (p = 0) and 44 patients (35%) in 2009 (p = 0.018). This clinically and statistically significant reduction occurred following reorganisation of existing resources on a budget neutral basis at MRHM and was facilitated by the enthusiastic support of a range of disciplines bridging the community and acute hospital interface. Measurement of admission to CT brain scan time is one of several audit parameters which can assess hospitals responsiveness to acute stroke.

How do people with Type 2 diabetes perceive and respond to cardiovascular risk?

OBJECTIVES

To explore how people with Type 2 diabetes perceive cardiovascular risk, and how those perceptions might affect their motivation to make lifestyle changes.

METHODS

The setting was a diabetes clinic in a UK teaching hospital. A qualitative study was conducted, using semistructured individual interviews and template analysis of content. The participants were 20 Type 2 diabetic patients, aged between 52 and 77 years, half with and half without cardiovascular disease (CVD).

RESULTS

Whether they had CVD or not, most people were aware they were at risk of it, of its causative factors, and possible effects. However, they were more likely to attribute it to unchangeable factors like 'stress' and 'heredity', than medical risk factors like cholesterol and smoking. Patients with pre-existing CVD correctly regarded their risk as higher than those without. Few saw any direct link between being diabetic per se and cardiovascular risk. Lifestyle changes were precipitated by major life events and motivated by family support, fear of complications, and a belief that one should follow doctors' advice. A common reaction to CVD and diabetes was stoical acceptance, allowing patients to view their lives positively, whilst living with unpredictable potentially disabling diseases.

CONCLUSIONS

Patients were unaware how strongly diabetes influences cardiovascular risk. Their ideas about risk were very different from those of conventional medicine, and provided individual rationales for making choices about treatment and risk-influencing behaviour. Contextual factors, such as family milieu, also influenced their behaviour. Clinicians should not assume patients share the same mental model of risk as they, and must be prepared to explore peoples' individual constructs and health beliefs.

Amnesic syndrome and severe ataxia following the recreational use of 3,4-methylene-dioxymethamphetamine (MDMA, 'ecstasy') and other substances

A 26-year-old woman suffered disseminated intravascular coagulation (DIC) and a brief respiratory arrest following recreational use of 3,4-methylene-dioxymethamphetamine (MDMA; 'ecstasy'), together with amyl nitrate, lysergic acid (LSD), cannabis and alcohol. She was left with residual cognitive and physical deficits, particularly severe anterograde memory disorder, mental slowness, severe ataxia and dysarthria. Follow-up investigations have shown that these have persisted, although there has been some improvement in verbal recognition memory and in social functioning. Magnetic resonance imaging and quantified positron emission tomography investigations have revealed: (i) severe cerebellar atrophy and hypometabolism accounting for the ataxia and dysarthria; (ii) thalamic, retrosplenial and left medial temporal hypometabolism to which the anterograde amnesia can be attributed; and (iii) some degree of fronto-temporal-parietal hypometabolism, possibly accounting for the cognitive slowness. The putative relationship of these abnormalities to the direct and indirect effects of MDMA toxicity, hypoxia and ischaemia is considered.

"Spiritual starvation?": a case series concerning christianity and eating disorders

METHOD

We describe the cases of four patients with eating disorders in whom complex interactions occurred among religious faith, pathogenesis of the eating disorder, and clinical management.

RESULTS

In some of the cases, religious beliefs seemed to provide a containment of maladaptive behaviors, partly through prayer and through a sense of belonging to the religious community. In other cases, it proved difficult to separate the concept of a punitive God from the illness process.

DISCUSSION

The cases are discussed with reference to a limited empirical literature. Similarities are noted between some religious institutions and eating disorder treatment regimes. This paper explores management issues, including the use of pastoral counseling and the ethics of addressing religious beliefs in therapy. We note the benefits of a rapprochement between psychiatry and religion.

FDG-PET analysis and findings in amnesia resulting from hypoxia

The assumptions underlying neuroimaging, and problems in its analysis and interpretation, are commonly underestimated in neuropsychology. The ways in which fluoro-deoxy-glucose (FDG) positron emission tomography (PET) data can be analysed are discussed. PET findings from four patients who had suffered severe amnesia, following episodes of acute hypoxia, are presented. These patients had shown evidence of medial temporal (hippocampal and parahippocampal) atrophy on MRI brain scans. The PET data were analysed in several different ways. The converging findings were that the patients showed bilateral thalamic hypometabolism, and there was also evidence of retrosplenial hypometabolism bilaterally. Cognitively, these patients performed most like other patients with medial temporal lesions, but the results indicate that structural lesions can have distal metabolic effects on structures elsewhere. These findings are interpreted in the light of neuroanatomical observations concerning parallel projections between medial temporal lobe structures and the thalamus, some of which pass via the retrosplenium.

Interictal regional slow activity in temporal lobe epilepsy correlates with lateral temporal hypometabolism as imaged with 18FDG PET: neurophysiological and metabolic implications

OBJECTIVES

The phenomenon of interictal regional slow activity (IRSA) in temporal lobe epilepsy and its relation with cerebral glucose metabolism, clinical data, MRI, and histopathological findings was studied.

METHODS

Interictal 18F-fluorodeoxyglucose positron emission tomography (FDG PET) was performed under continuous scalp EEG monitoring in 28 patients with temporal lobe epilepsy not associated with intracranial foreign tissue lesions, all of whom subsequently underwent resective surgery. Regions of interest (ROIs) were drawn according to a standard template. IRSA was considered lateralised when showing a 4:1 or greater ratio of predominance on one side.

RESULTS

Sixteen patients (57%) had lateralised IRSA which was always ipsilateral to the resection and of maximal amplitude over the temporal areas. Its presence was significantly related to the presence of hypometabolism in the lateral temporal neocortex (p=0.0009). Logistic regression of the asymmetry indices for all measured cerebral regions confirmed a strong association between IRSA and decreased metabolism of the posterior lateral temporal neocortex only (p=0.009). No significant relation could be shown between slow activity and age at onset, duration of the epilepsy, seizure frequency, and MRI evidence for hippocampal atrophy. Furthermore, IRSA was not specifically related to mesial temporal sclerosis or any other pathology.

CONCLUSIONS

Interictal regional slowing in patients with temporal lobe epilepsy not associated with a mass lesion is topographically related to the epileptogenic area and therefore has a reliable lateralising, and possibly localising, value. Its presence is irrelevant to the severity or chronicity of the epilepsy as well as to lateral deactivation secondary to neuronal loss in the mesial temporal structures. Although slow EEG activity is generally considered as a non-specific sign of functional disturbance, interictal regional slowing in temporal lobe epilepsy should be conceptualised as a distinct electrographic phenomenon which is directly related to the epileptogenic abnormality. The strong correlation between interictal regional slowing and lateral temporal hypometabolism suggests in turn that the second may delineate a field of reduced neuronal inhibition which can receive interictal and ictal propagation.

Strategies to prevent thrombosis in xenotransplants

Coagulation remains a major barrier to successful xenotransplantation. Identification of the role of complement activation in HAR and prevention of complement activation by high expression of DAF and CD59 has largely overcome HAR. Understanding the molecular basis of DXR and identification of novel strategies to prevent activation of endothelial cells using monoclonal antibodies, soluble inhibitors of coagulation, vaccination, antisense constructs, and recombinant DNA technology offers the promise of overcoming the thrombosis associated with xenotransplantation.

Regional differences in cerebral blood flow and glucose utilization in diabetic man: the effect of insulin

To determine the effect of insulin on regional cerebral blood flow (rCBF) and glucose metabolism (CMRglu), we performed quantitative dynamic PET scanning of labeled water (H215O) and deoxyglucose (18FDG) using two protocols in 10 diabetic men. In protocol A, to test reproducibility of the technique, insulin was infused at 1.5 mU.kg-1.min-1 twice (n = 5). In protocol B, low (0.3 mU.kg-1.min-1) and high (3 mU.kg-1.min-1) dose insulin was given on separate occasions (n = 5). Euglycemia (5 mmol/L) was maintained by glucose infusion. In protocol A, CMRglu was 6% higher during the first infusion, and catecholamines were also increased, indicating stress. Blood flow was not different. Changing free insulin levels from 20.5 +/- 4.8 to 191 +/- 44.5 mU/L (P < 0.001, low versus high dose, protocol B) did not alter total or regional CMRglu (whole brain 36.6 +/- 4.0 versus 32.8 +/- 6.2 mumol.100 g-1.min-1, P = 0.32) or CBF (41.7 +/- 5.1 and 45.6 +/- 9.7 mL.100 g-1.min-1, P = 0.4) or rCBF. In cerebellum, CMRglu was lower than in cortex and the ratio between rate constants for glucose uptake and phosphorylation (K1 and k3) was reversed. There are regional differences in cerebral metabolic capacity that may explain why cerebral cortex is more sensitive to hypoglycemia than cerebellum. Brain glucose metabolism is not sensitive to insulin concentration within the physiologic range. This suggests that intracerebral insulin receptors have a different role from those in the periphery.

[Effect of bed nets impregnated with deltamethrin on malaria morbidity in an area of the Brazilian Amazones]

In 1992 an investigation regarding the value of insecticide impregnated mosquito nets was conducted in the municipality of Costa Marques, Rondonia. Impregnated mosquito nets gave similar protection to those not impregnated, without modifying the incidence of infection during the season of low transmission. The multivariate analysis for age and antibody titre showed a significant protection of impregnated nets against the risk of infection only in the season of high transmission, when bed nets were used more correctly. There was no difference in the effect of both kinds of bed nets in the prevention of high parasitaemia. At the end of the study, there was a reduction of the prevalence of splenomegaly in both groups but hematocrit values rose to normal in the below 15 year olds using impregnated nets.

[Comparative study of meglumine antimoniate, pentamidine isethionate and aminosidine sulfate in the treatment of primary skin lesions caused by Leishmania (Viannia) braziliensis]

With the aim of comparing the therapeutic efficacy, tolerability and toxicity of meglumine antimoniate, aminosidine sulphate and pentamidine isethionate, a field study was conducted on randomized treatment of patients with primary cutaneous leishmaniasis due to Leishmania (Viannia) braziliensis (L(V)b), in Corte de Pedra, BA, from October 1992 up to January 1993. Forty six patients were treated and distributed into three groups, two with 15 and one with 16 subjects. All patients were submitted to clinical examination, histopathological and immunological investigations, as diagnostic criterium. All patients were treated by intramuscular route. Group 1 received pentamidine 4 mg/kg/every 2 days, for 8 applications; Group 2 received aminosidine 20 mg/kg/day, for 20 days, and Group 3 received meglumine 10 mg Sbv/kg/day, for 20 days. Failure of therapy was defined as ulceration of the skin lesion four months after treatment. Such failure occurred in five cases as follows: two cases in patients of group 1 one case in patients of group 2, and two cases in group 3, after the first year of follow up. In the evaluation after three years we reviewed fifteen patients, five in each group; except for one in Group 3, all of them were cured. Statistical significance of the results between the three schedules used was not verified.

Cardiac function, metabolism and perfusion in Duchenne and Becker muscular dystrophy

We studied 23 DMD and eight BMD patients using cardiac echo, 24 h ECG and positron emission tomography (PET) with the radiotracers N-13 ammonia and F-18 fluorine deoxyglucose. The ECG was abnormal in 23 cases with alterations in the PR and/or QT intervals, abnormal Q waves in the lateral leads and ST segment depression. Twenty-four hour ECG showed that patients were more likely to produce premature ventricular ectopic beats with advancing age and 17 patients had paroxysmal ST segment depression. LV function was normal or mildly reduced in 24 cardiac echoes. PET studies were visibly abnormal in 15 patients. Regional perfusion defects involving the apex, lateral or anterior left ventricular walls were present, nine cases demonstrated a corresponding increase in glucose metabolism. Three out of 15 demonstrated matched perfusion/metabolism defects. One BMD had severe LV dilation with globally poor perfusion and metabolism. The abnormalities seen with PET were confirmed with both quantitative and semi-quantitative analysis of radioactive counts. Similar results were obtained for both DMD and BMD, where both groups demonstrated significant regional perfusion/metabolism mismatches. We have shown a reduced uptake of N-13 ammonia which is indicative of a reduction in myocardial perfusion. The use of N-13 ammonia to measure perfusion has been validated in animal studies. PET with either N-13 ammonia- or oxygen labelled water can be used to measure myocardial perfusion. We chose N-13 ammonia as this was most readily available to us.

Human interaction with technology: the accidental user

Information technology is part of a growing number of applications in work and everyday life. It seems inevitable that the average person soon will have to interact with information technology in many ways, even when there is no desire to do so. Examples include finding a book in a library, personal financial transactions, the health sector, traffic and transportation, process control, etc. People who in this way are forced to interact with information technology shall be called accidental users. The accidental users poses a particular challenge to the design of technological artefacts because the disciplines of dealing with human-machine interaction are predicated on the assumption that users are motivated and have a minimum level of knowledge and skills. In particular, models of 'human error' and human reliability implicitly assume that users are benign and only fail as anticipated by designers. In this paper we investigate the extent to which current models of human erroneous actions and cognitive reliability can be used to account for interactions between accidental users and technology.

[Effectiveness of aminosidine sulphate in severe visceral leishmaniasis, resistant to the treatment with pentavalent antimony]

A grave kala-azar infection in a 14 years old boy is described. The leishmanial infection failed to respond to ten interrupted courses of glucantime of variable duration (14-56 days) at a dose of 20mg Sb5/kg/day. However a favorable response occurred to intramuscular aminosidine sulphate (20mg/kg/day) for 20 days. This same regimen was repeated 20 days later. After the first treatment splenic puncture parasite density fell from 50 amastigotes per oil immersion field to 3 amastigotes in 10 fields. A further splenic puncture 7 months after treatment was negative. The marked hepatoesplenomegaly gradually resolved over 26 months follow up and he gained 13 kilograms in weight. After aminosidine sulphate therapy his Montenegro reaction become positive and his lymphocytes responded to leishmania antigens.

Whole-body 18F-fluorodeoxyglucose positron emission tomography in preoperative evaluation of lung cancer

Despite use of computed tomography, some lung cancer patients are found to have unresectable disease at surgery, or they present early with metastases. We studied whether whole-body positron emission tomography (PET) with 18F-fluorodeoxyglucose (18FDG) would improve the preoperative detection of metastases. We retrospectively analysed 34 patients with "operable" non-small-cell lung cancer who underwent 18FDG PET after routine assessment. Management changes produced by the PET scan and confirmatory tests were reviewed. PET identified unsuspected malignant lesions in 10 (29%) patients. Management changes occurred in 14 (41%), including 6 (18%) patients who were changed to non-surgical therapy. These data suggest that whole-body 18FDG PET improves preoperative assessment of lung cancer patients.

Clinical and immunopathological aspects of disseminated cutaneous leishmaniasis

The clinico-pathological and immunological findings in eight patients from Bahia, Brazil with disseminated cutaneous leishmaniasis are described. This condition differs from anergic diffuse cutaneous leishmaniasis (DCL) and from classical American cutaneous leishmaniasis (ACL). The number of lesions in these patients ranged from 75 to 800 and were characterized by papules and an acneiform type of lesion with a few ulcers rather than nodules that are the main characteristic of DCL. On the other hand the high incidence of mucosal disease (38%) in patients with disseminated cutaneous leishmaniasis make the prevalence of mucosal involvement in this condition higher than that observed in ACL. L. amazonensis (five cases) and L. braziliensis (two cases) were the causal agents in the patients where the infecting agent was characterized. Antibody titers in disseminated cutaneous leishmaniasis were higher than those observed in ACL and patients with the highest antibody titers had mucosal involvement. Abnormalities in cellular immunity that are not observed in ACL such as decrease in CD4+ cells and absence of T cell response to leishmania antigen were observed in several patients with disseminated cutaneous leishmaniasis but restoration of these abnormalities occurred after treatment. In spite of the great number of lesions, the therapeutic response was good in six patients with disappearance of the lesions in a period shorter than that observed in ACL. In the two patients that presented therapeutic failure the causal agent was L. amazonensis. In such patients there was a predominance of ulcerated lesions, and a high titer of antibody was detected.

[The first 13 years of controlling Chagas' disease in Mambaí, Goiás, Brazil 1980-1992]

The Mambaí Project was launched in 1980 for the purpose of making a longitudinal clinical-epidemiologic study of Chagas' disease and of serving as a pilot program for the Ministry of Health of Brazil. At the beginning of the project, a census was carried out, the housing units were evaluated, and clinical examination and laboratory tests were performed on the population. After a phase of massive attack with insecticides, ongoing epidemiologic surveillance was instituted in order to detect residual foci of triatomine bugs in all the housing units in the municipality. The campaign included a program of health education combined with community participation. All infested housing units were selectively fumigated. In 1988 a new census was carried out, together with a serologic survey of children born after the control program was initiated. This article describes the results of epidemiologic surveillance during the first 13 years of the program. The prevalence of T. infestans in the housing units diminished to levels that suggest that vector transmission of the disease in Mambaí has been stopped. However, the risk of reinfestation from neighboring areas without control programs and the risk of colonization by secondary T. sordida vectors are factors that should be carefully monitored.

Improved diabetes care in a UK health district

The present study reports an analysis of diabetes care in general practice in a London Health District. A specialist nurse facilitator used various techniques to obtain practice information building up individual practice profiles. Four groups of constraints were identified as affecting the provision of GP diabetes care. Individual practice plans were formulated, working with key staff, to apply various interventions to ameliorate identified constraints. Using a non-prescriptive approach, GPs were encouraged to become involved in diabetes care in the way they felt most appropriate for their practice. Using this method, GP involvement in diabetes care has increased from 17 to 53% during the three years of the study.

Otolaryngology-head and neck surgery in the Canadian military: practice trends

The practice of medicine in the Canadian military is poorly publicized except in times of war. The specialty of otolaryngology-head and neck surgery is not well known, even in medical circles. To correct this deplorable ignorance, a review was conducted on the otolaryngologic activities within the Canadian Forces. This revealed a dynamic specialty whose many contributions warrant acknowledgment. Starting with Major-General M.J.C.E. Fiset, who was the first such specialist in Canada, military otolaryngologists have maintained excellent standards of medical practice for the benefit of the Canadian soldier. This paper traces the development of military otolaryngology in Canada. Trends in the practice of this versatile specialty are presented.

Quantitative assessment of diagnostic ability

This paper describes variables critical to diagnostic thinking that are based on research by Bordage and Grant & Marsden on the diagnostic thinking of medical students and experienced doctors. The purpose of the study is to use their findings to develop an inventory of diagnostic thinking. A 56-item diagnostic thinking inventory was initially developed; each item contains a stem followed by a 6-point, semantic differential scale. The inventory is designed to measure two aspects of diagnostic thinking: the degree of flexibility in thinking and the degree of knowledge structure in memory. The specific goal of the study is to determine which items discriminate best between weaker and stronger diagnosticians and to reduce the inventory to only those items which significantly contribute to the overall score. Thirty subjects from nine groups, each representing a distinct phase of medical education and clinical practice, participated, namely first- and third-year clinical medical students, house officers, senior house officers, registrars, senior registrars, consultants, trainees in general practice, and general practitioners, all from the UK (n = 270). Discrimination indices were calculated for each item. The revised version of the inventory contains 41 items. All the subjects found the exercise meaningful and the resulting scores showed variance and discrimination. The inventory will eventually be used to assess individual student's and clinician's diagnostic thinking and to plan ways of improving their diagnostic thinking.

The learning needs in diabetes of general practitioners

The aim of the study was to determine the learning needs of General Practitioners (GPs) in diabetes. A postal questionnaire was sent to all GPs in South East Thames Region (England). The level of interest in continuing professional education in diabetes is sufficient to merit production of tailored learning materials and opportunities. Eighty-three percent of GPs would definitely or probably avail themselves of the opportunity even if they did have to pay. This percentage represents a figure of over 780 GPs. They are most keen to learn the clinical and other skills associated with diabetes and its management. A large number, 71%, requested education on retinal examination and adjustment of insulin, 56% on adjustment of tablet therapy, and 51% on the management of children with diabetes. Individual study materials, backed up by small group meetings and video material would be the most appreciated format. A course of study divided into half-hourly periods adding up to a total of about 5 h might be the most widely acceptable format. GPs would most like to study with other GPs from local practices and with hospital staff. Group work might best be designed to incorporate both an experienced GP, if one were available, and a consultant. The materials themselves might also best be designed and written by such a partnership.

[Information-related changes in attitude to mucocutaneous leishmaniasis of a population from an endemic region of the south of Bahia]

The mutilant nature of the mucosal form of leishmaniasis can cause alterations in personal relations. To identify the level of understanding of leishmaniasis and the psychological reaction to it patients and houseowners in an endemic area of Bahia were interviewed. Several false beliefs were identified and there was a strong tendency to reject mutilated patients among the population for a false fear of contagion. Possibly future clarification of the real nature of leishmaniasis could change such a negative attitude among the resident population.

Senior house officers and their training. I. Personal characteristics and professional circumstances

To assess the experience and perceptions of training of senior house officers in medicine a population survey of senior house officer training was conducted on senior house officers, registrars, senior registrars, and consultants in six medical specialties in South East Thames region by interview and postal questionnaire. The overall response rate was 72%, varying from 62% to 83% according to status and from 61% to 80% according to specialty. Although most of the 226 senior house officer respondents were aged 28 or under (168/225), had been qualified for four years or less (168/225) and were British (176/223), a quarter were older and had been qualified for five years or more; in all, 17 other nationalities were represented. Twenty two were aged over 33, and 17 had been qualified for more than 10 years. Thirty five senior house officers worked more than the mode of the distribution of duty rotas (one in three). Among postgraduate qualifications achieved or pursued, those related to general practice were highly represented (164 examinations); 111 senior house officers intended becoming general practitioners, 63 non-teaching hospital consultants, and 34 university or NHS teaching staff. Analysis of career progression showed that an appreciable number (31/221) had had more than three senior house officer posts. The findings indicate that the main implications for training and education are time for study, careers advice, and revision of educational programmes.

Senior house officers and their training. II. Perceptions of service and training

Aspects of teaching and learning at senior house officer level in South East Thames region were investigated by analysis of the responses of consultants, senior registrars, registrars, and senior house officers to a postal questionnaire. Responses to sections about who teaches senior house officers, how senior house officers learn, and the relation between the service and training elements of these posts varied significantly, according to the status of the respondents; certain grades commonly overestimated their own contribution when compared with the estimates of the other grades. Although the replies of senior house officers showed that they were taught by various grades, 47% of this group did not regard the consultant as their main teacher. Senior registrars and registrars rather than consultants were regarded by senior house officers as best at teaching (63% v 48% respectively). Consultants and registrars were considered to require more commitment to training, personal educational training, and to be more approachable. Inquiry about teaching methods used most by senior house officers showed absence of a systematic approach to training. Only about half of senior house officers cited ward rounds with consultants. Views on the relation between training and service were significantly different among grades, but there was general dissatisfaction. Overall, the findings disclosed the ineffectiveness of senior house officer training posts. This arises from lack of a clear distinction between training and service elements, of educational training for teachers, of a clear contractual obligation to teach im the consultant grade, and of allotted time for training and study for the teachers and senior house officers respectively. Reversal of these current trends is needed for senior house officer posts to fulfil their main training function.