Factors Contributing to Delays to Accessing Appendectomy in Low- and Middle-Income Countries: A Scoping Review

BACKGROUND

Appendicitis is one of the most common emergency surgical conditions worldwide. Delays in accessing appendectomy can lead to complications. Evidence on these delays in low- and middle-income countries (LMICs) is lacking. The aim of this review was to identify and synthesise the available evidence on delays to accessing appendectomy in LMICs.

METHODS

This scoping review followed the Preferred Reporting Items for Systematic Reviews and Meta-analysis Extension for Scoping Reviews framework. The delays and their interconnectivity in LMICs were synthesised and interpreted using the Three Delays framework. We reviewed Africa Wide EBSCOhost, PubMed-Medline, Scopus, Web of Science, African Journals Online (AJOL), and Bioline databases.

RESULTS

Our search identified 21 893 studies, of which 78 were included in the final analysis. All of the studies were quantitative. Fifty per cent of the studies included all three types of delays. Delays in seeking care were influenced by a lack of awareness of appendicitis symptoms, and the use of self and alternative medication, which could be linked to delays in receiving care, and the barrier refusal of medical treatment due to fear. Financial concerns were a barrier observed throughout the care pathway.

CONCLUSION

This review highlighted the need for additional studies on delays to accessing appendectomy in additional LMICs. Our review demonstrates that in LMICs, persons seeking appendectomy present late to health-care facilities due to several patient-related factors. After reaching a health-care facility, accessing appendectomy can further be delayed owing to a lack of adequate hospital resources.

Evaluating a novel patient pathway to manage symptomatic breast referrals (the blue flag clinic): a longitudinal observational study

INTRODUCTION

A novel referral pathway for exhibited breast symptom (EBS) referrals to manage increasing referrals of urgent suspected cancer (USC) was implemented in our trust. We report on the safety and effect on compliance with the 2-week-wait rule (2WW).

METHODS

A single-centre longitudinal observational study included all patients referred to a UK breast unit during 13 May 2019 to 27 March 2020 (period 1) and 8 February 2021 to 31 January 2022 (period 2). USC referrals were assessed in a one-stop clinic (red flag clinic [RFC]); EBS referrals were assessed in a new clinic in which clinical evaluation was performed and imaging occurred subsequently (blue flag clinic [BFC]). Patients were followed up to determine the symptomatic interval cancer rate.

RESULTS

There were 9,695 referrals; 1,655 referrals (17%) were assessed in the BFC after 63 exclusions. Some 95.9% of patients had a benign clinical examination (P1/P2), 80.1% had imaging (mammogram or ultrasound) and 4% had a tissue biopsy. In total, 16/1,655 (0.97%) BFC patients and 510/7,977 (8.2%) RFC patients were diagnosed with breast cancer (breast cancer detection rate). Some 1,631 patients (with 1,639 referrals) were discharged and followed up for a median of 17 months (interquartile range 12-32) with one subsequent cancer diagnosis (symptomatic interval cancer rate, 0.06%). Implementation of the BFC pathway increased 3-month average trust performance of USC referrals with 2WW standard from 8.5% to 98.7% (period 1) and from 30% to 66% (period 2).

CONCLUSIONS

The BFC pathway for EBS patients is safe and implementation led to improvement against the 2WW target for USC referrals, ensuring resources are prioritised to patients with the highest likelihood of breast cancer.

Monitoring Cochlear Health With Intracochlear Electrocochleography During Cochlear Implantation: Findings From an International Clinical Investigation

OBJECTIVES

Electrocochleography (ECochG) is emerging as a tool for monitoring cochlear function during cochlear implant (CI) surgery. ECochG may be recorded directly from electrodes on the implant array intraoperatively. For low-frequency stimulation, its amplitude tends to rise or may plateau as the electrode is inserted. The aim of this study was to explore whether compromise of the ECochG signal, defined as a fall in its amplitude of 30% or more during insertion, whether transient or permanent, is associated with poorer postoperative acoustic hearing, and to examine how preoperative hearing levels may influence the ability to record ECochG. The specific hypotheses tested were threefold: (a) deterioration in the pure-tone average of low-frequency hearing at the first postoperative follow-up interval (follow-up visit 1 [FUV1], 4 to 6 weeks) will be associated with compromise of the cochlear microphonic (CM) amplitude during electrode insertion (primary hypothesis); (b) an association is observed at the second postoperative follow-up interval (FUV2, 3 months) (secondary hypothesis 1); and (c) the CM response will be recorded earlier during electrode array insertion when the preoperative high-frequency hearing is better (secondary hypothesis 2).

DESIGN

International, multi-site prospective, observational, between groups design, targeting 41 adult participants in each of two groups, (compromised CM versus preserved CM). Adult CI candidates who were scheduled to receive a Cochlear Nucleus CI with a Slim Straight or a Slim Modiolar electrode array and had a preoperative audiometric low-frequency average thresholds of ≤80 dB HL at 500, 750, and 1000 Hz in the ear to be implanted, were recruited from eight international implant sites. Pure tone audiometry was measured preoperatively and at postoperative visits (FUV1 and follow-up visit 2 [FUV2]). ECochG was measured during and immediately after the implantation of the array.

RESULTS

From a total of 78 enrolled individuals (80 ears), 77 participants (79 ears) underwent surgery. Due to protocol deviations, 18 ears (23%) were excluded. Of the 61 ears with ECochG responses, amplitudes were < 1 µV throughout implantation for 18 ears (23%) and deemed "unclear" for classification. EcochG responses >1 µV in 43 ears (55%) were stable throughout implantation for 8 ears and compromised in 35 ears. For the primary endpoint at FUV1, 7/41 ears (17%) with preserved CM had a median hearing loss of 12.6 dB versus 34/41 ears (83%) with compromised CM and a median hearing loss of 26.9 dB ( p < 0.014). In assessing the practicalities of measuring intraoperative ECochG, the presence of a measurable CM (>1 µV) during implantation was dependent on preoperative, low-frequency thresholds, particularly at the stimulus frequency (0.5 kHz). High-frequency, preoperative thresholds were also associated with a measurable CM > 1 µV during surgery.

CONCLUSIONS

Our data shows that CM drops occurring during electrode insertion were correlated with significantly poorer hearing preservation postoperatively compared to CMs that remained stable throughout the electrode insertion. The practicality of measuring ECochG in a large cohort is discussed, regarding the suggested optimal preoperative low-frequency hearing levels ( < 80 dB HL) considered necessary to obtain a CM signal >1 µV.

Access to health care for people with stroke in South Africa: a qualitative study of community perspectives

Background

Incidence of stroke is increasing in sub-Saharan Africa. People who survive stroke experience disability and require long-term care. Health systems in South Africa (SA) are experiencing important challenges, and services in the public health system for people with stroke (PWS) are fragmented. We aimed to explore the perspectives and experiences of PWS related to stroke care services to inform health system strengthening measures.

Methods

In-depth interviews with 16 PWS in urban and rural areas in the Western and Eastern Cape Provinces of SA were conducted between August and October 2020. PWS were recruited through existing research networks, non-government organisations and organisations of persons with disabilities by snowball sampling. Interviews were transcribed, coded, and thematically analysed. We used the conceptual framework of access to health care as proposed by Levesque et al. to map and inform barriers to accessing health care from the user perspective.

Results

PWS recognised the need for health care when they experienced signs of acute stroke. Health literacy on determinants of stroke was low. Challenges to accessing stroke care include complex pathways to care, physical mobility related to stroke, long travel distances and limited transport options, waiting times and out of pocket expenses. The perceived quality of services was influenced by cultural beliefs, attitudinal barriers, and information challenges. Some PWS experienced excellent care and others particularly poor care. Positive staff attitude, perceived competence and trustworthiness went in hand with many technical and interpersonal deficits, such as long waiting times and poor staff attitude that resulted in poor satisfaction and reportedly poor outcomes for PWS.

Conclusions

Strategic leadership, governance and better resources at multiple levels are required to address the unmet demands and needs for health care of PWS. Stroke care could be strengthened by service providers routinely providing information about prevention and symptoms of stroke, treatment, and services to patients and their social support network. The role of family members in continuity of care could be strengthened by raising awareness of existing resources and referral pathways, and facilitating connections within services.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-022-07903-9.

A Culturally Relevant Smartphone-Delivered Physical Activity Intervention for African American Women: Development and Initial Usability Tests of Smart Walk

Background

Smart Walk is a culturally relevant, social cognitive theory–based, smartphone-delivered intervention designed to increase physical activity (PA) and reduce cardiometabolic disease risk among African American (AA) women.

Objective

This study aimed to describe the development and initial usability testing results of Smart Walk.

Methods

Smart Walk was developed in 5 phases. Phases 1 to 3 focused on initial intervention development, phase 4 involved usability testing, and phase 5 included intervention refinement based on usability testing results. In phase 1, a series of 9 focus groups with 25 AA women (mean age 38.5 years, SD 7.8; mean BMI 39.4 kg/m2, SD 7.3) was used to identify cultural factors associated with PA and ascertain how constructs of social cognitive theory can be leveraged in the design of a PA intervention. Phase 2 included the analysis of phase 1 qualitative data and development of the structured PA intervention. Phase 3 focused on the technical development of the smartphone app used to deliver the intervention. Phase 4 consisted of a 1-month usability trial of Smart Walk (n=12 women; mean age 35.0 years, SD 8.5; mean BMI 40 kg/m2, SD 5.0). Phase 5 included refinement of the intervention based on the usability trial results.

Results

The 5-phase process resulted in the development of the Smart Walk smartphone-delivered PA intervention. This PA intervention was designed to target social cognitive theory constructs of behavioral capability, outcome expectations, social support, self-efficacy, and self-regulation and address deep structure sociocultural characteristics of collectivism, racial pride, and body appearance preferences of AA women. Key features of the smartphone app included (1) personal profile pages, (2) multimedia PA promotion modules (ie, electronic text and videos), (3) discussion boards, and (4) a PA self-monitoring tool. Participants also received 3 PA promotion text messages each week.

Conclusions

The development process of Smart Walk was designed to maximize the usability, cultural relevance, and impact of the smartphone-delivered PA intervention.

A 58-Year-Old Man With Fatigue, Weight Loss, and Diffuse Miliary Pulmonary Opacities

CASE PRESENTAION

A 58-year-old man presented with a 6-month history of profound fatigue and a weight loss of 35 to 40 pounds. He reported occasional night sweats and mildly painful knees and elbows without swelling or redness. He denied respiratory symptoms, rashes, or fevers. He had no respiratory symptoms. The patient's history was significant for rheumatoid arthritis (with arthralgias and joint involvement), paroxysmal atrial fibrillation, and hypothyroidism. His medications included digoxin and metoprolol. He had been taking methotrexate and low-dose prednisone (5 mg) for approximately 10 years but discontinued taking these medications 2 years prior to current presentation. Originally from West Virginia, the patient had relocated to Arizona during the early 1980s. There was no history of international travel or TB. He had no exposure history to birds, bird feathers, or mold; however, he did report exposure to dust at his current job as a home building superintendent. He reported a 10 pack-year history of smoking, having quit 20 years ago. His family history was significant for renal sarcoidosis in his mother.

Enhanced Excitotoxicity in Primary Feline Neural Cultures Exposed to Feline Immunodeficiency Virus (FIV)

The ability of feline immunodeficiency virus (FIV) to induce neurodegenerative changes in vitro similar to those due to HIV was examined as a potential model to examine the mechanisms underlying AIDS dementia. Primary cultures of feline neural tissue (neurons, astrocytes and microglia) were established from E40-E57 fetal cat cortex and challenged by inoculation with the NCSU₁ strain of FIV. Proviral FIV was detected in the cultures and correlated with the presence of microglia. No direct toxicity of FIV was seen. Stimulation of FIV-inoculated cortical cultures with 20 uM glutamate resulted in a greatly enhanced acute swelling response in approximately 14-24% of the neurons and an increase in the number of dead cells after 24 h relative to control cultures. The enhanced responses were due to an increase in the sensitivity of the cells to glutamate and were dependent on the presence of a soluble factor in the medium. The similarity of the indirect excitoxic effects of FIV to current models of HIV-gp120 neurotoxicity and the versatility of the in vitro cultures, indicate that FIV should provide a valuable model for the investigation of the mechanisms of neurodegeneration in AIDS dementia.

Randomized clinical trial on the effect of fibrin sealant on latissimus dorsi donor-site seroma formation after breast reconstruction

BACKGROUND

Latissimus dorsi (LD) flap procedures comprise 50 per cent of breast reconstructions in the UK. They are frequently complicated by seroma formation. Fibrin sealants may reduce seroma volumes at the donor site. The aim was to investigate the effect of fibrin sealant (Tisseel(®)) on total seroma volumes from the breast, axilla and back (donor site) after LD breast reconstruction. Secondary outcomes were specific back seroma volumes together with incidence and severity of wound complications.

METHODS

Consecutive women undergoing implant-assisted or extended autologous LD flap reconstruction were randomized to either standard care or application of fibrin sealant to the donor-site chest wall. All participants were blinded for the study duration but assessors were only partially blinded. Non-parametric methods were used for analysis.

RESULTS

A total of 107 women were included (sealant 54, control 53). Overall back seroma volumes were high, with no significant differences between control and sealant groups over 3 months. Fibrin sealant failed to reduce in situ back drainage volumes in the 10 days after surgery, and did not affect the rate or volume of seromas following drain removal.

CONCLUSION

This randomized study, which was powered for size effect, failed to show any benefit from fibrin sealant in minimizing back seromas after LD procedures.

P2-16-07: A Randomised Controlled Trial To Evaluate the Role of Tisseel, a Fibrin Sealant on Seroma Formation in Latissimus dorsi Breast Reconstruction

Introduction: Donor site seromas are common complications following Latissimus dorsi breast reconstructions (LDBR), as shown in the UK National Mastectomy and Breast Reconstruction audit. Level I clinical evidence following the performance of an RCT supports ‘fixation’ of the back skin flaps by quilting sutures1. Fibrin sealants (Tisseel) have been postulated to reduce seromas after simple mastectomy and axillary dissections2, but their role in reducing donor site seromas after breast reconstruction has yet to be performed in a ‘robust’ clinical trial. The aim of this RCT was to compare Tisseel against Control (no Tisseel) on the incidence of seromas after LDBR.

Methods: In an ethics approved single centre, single-blinded study comprising 2 surgeons from 2005–2010; 106 women were randomised to either Control (52) or Tisseel (54) interventions after immediate or delayed breast reconstructions. Sixteen patient's were excluded as follows due to incomplete data at 3 months or re-operations of the donor site for complications. The types of breast reconstructions comprised implant-assisted LD (LDI) in 45 women, 23 extended LD flaps (ELD) and 23 ELD with implant (ELDI). Immediate breast reconstructions (n=87) comprised the majority compared to only 4 delayed procedures. Intraoperative drains were placed to the breast, axilla and donor site (x two) as per standard practice. A 0.5% fibrinogen concentration was used in a hydraulic hand-held Tisseel spray application to the donor site chest wall over 60 seconds. Two stay sutures were pre-placed 2 cm adjacent to the donor wound skin edges above and below prior to the Tisseel application. In the control group, 2 drains only were placed. The primary outcome measure was the total seroma volumes from all the sites over 3 months. This was used for the power calculation of the sample size and showed a requirement for a minimum of 95 women. Secondary outcomes included the volumes of the donor site seromas, and the frequency of post-drain removal donor site aspirations of all symptomatic seromas by patient self-report.

Results: The effect of Tisseel glue was to reduce the mean total drain (breast, axilla and back) volume from 2170ml to 1919ml (P=0.05, Mann-Whitney) within 7–10 days. The donor site seroma volumes were similar between the 2 groups over 3 months. The mean donor site total drain volumes (LD donor site drain volume and symptomatic donor site aspirations) were 5412ml in the Control group (840-6252), compared to the Tisseel group producing 4646ml (5384-738). There were no statistical differences between the frequencies or volumes of patient reported seromas aspirated post-drain removal between the two groups. This comprised a mean of 4 aspirations (range 0–13) in the Control group compared to a mean of 9 aspirations (range 0–11) after the use of Tisseel (P=0.548).

Conclusion: Tisseel glue may reduce the ‘early’ effect of seroma development, but has not shown any significant role in minimising the potential ‘shearing’ of the donor site skin flaps causing later seroma formation. Current evidence recommends quilting sutures as the gold-standard in reducing this complication.

1. Daltrey I et. al. BJS 2006; 93(7):825–830.

2. Jain PK et. al. BJS 2004; 91:54–60.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-16-07.

Building capacity for antiretroviral delivery in South Africa: a qualitative evaluation of the PALSA PLUS nurse training programme

BACKGROUND

South Africa recently launched a national antiretroviral treatment programme. This has created an urgent need for nurse-training in antiretroviral treatment (ART) delivery. The PALSA PLUS programme provides guidelines and training for primary health care (PHC) nurses in the management of adult lung diseases and HIV/AIDS, including ART. A process evaluation was undertaken to document the training, explore perceptions regarding the value of the training, and compare the PALSA PLUS training approach (used at intervention sites) with the provincial training model. The evaluation was conducted alongside a randomized controlled trial measuring the effects of the PALSA PLUS nurse-training (Trial reference number ISRCTN24820584).

METHODS

Qualitative methods were utilized, including participant observation of training sessions, focus group discussions and interviews. Data were analyzed thematically.

RESULTS

Nurse uptake of PALSA PLUS training, with regard not only to ART specific components but also lung health, was high. The ongoing on-site training of all PHC nurses, as opposed to the once-off centralized training provided for ART nurses only at non-intervention clinics, enhanced nurses' experience of support for their work by allowing, not only for ongoing experiential learning, supervision and emotional support, but also for the ongoing managerial review of all those infrastructural and system-level changes required to facilitate health provider behaviour change and guideline implementation. The training of all PHC nurses in PALSA PLUS guideline use, as opposed to ART nurses only, was also perceived to better facilitate the integration of AIDS care within the clinic context.

CONCLUSION

PALSA PLUS training successfully engaged all PHC nurses in a comprehensive approach to a range of illnesses affecting both HIV positive and negative patients. PHC nurse-training for integrated systems-based interventions should be prioritized on the ART funding agenda. Training for individual provider behaviour change is nonetheless only one aspect of the ongoing system-wide interventions required to effect lasting improvements in patient care in the context of an over-burdened and under-resourced PHC system.

The Practical Approach to Lung Health in South Africa (PALSA) intervention: respiratory guideline implementation for nurse trainers

AIM

This paper describes the design, facilitation and preliminary assessment of a 1-week cascade training programme for nurse trainers in preparation for implementation of the Practical Approach to Lung Health in South Africa (PALSA) intervention, tested within the context of a pragmatic cluster randomized controlled trial in the Free State province. PALSA combines evidence-based syndromic guidelines on the management of respiratory disease in adults with group educational outreach to nurse practitioners.

BACKGROUND

Evidence-based strategies to facilitate the implementation of primary care guidelines in low- to middle-income countries are limited. In South Africa, where the burden of respiratory diseases is high and growing, documentation and evaluation of training programmes in chronic conditions for health professionals is limited.

METHOD

The PALSA training design aimed for coherence between the content of the guidelines and the facilitation process that underpins adult learning. Content facilitation involved the use of key management principles (key messages) highlighted in nurse-centred guidelines manual and supplemented by illustrated material and reminders. Process facilitation entailed reflective and experiential learning, role-playing and non-judgemental feedback.

DISCUSSION AND RESULTS

Preliminary feedback showed an increase in trainers' self-awareness and self-confidence. Process and content facilitators agreed that the integrated training approach was balanced. All participants found that the training was motivational, minimally prescriptive, highly nurse-centred and offered personal growth.

CONCLUSION

In addition to tailored guideline recommendations, training programmes should consider individual learning styles and adult learning processes.

Analysis of clinical decision-making in multi-disciplinary cancer teams

Management decisions for patients with cancer are frequently taken within the context of a multi-disciplinary team (MDT). There is little known, however, about decision-making at team meetings and whether MDT decisions are all implemented. This study evaluated team decision-making in upper gastrointestinal cancer. Consecutive MDT treatment decisions were recorded for patients with oesophageal, gastric, pancreatic and peri-ampullary tumours. Implementation of MDT decisions was investigated by examining hospital records. Where decisions were implemented it was recorded as concordant and discordant if the decision changed. Reasons for changes in MDT decisions were identified. 273 decisions were studied and 41 (15.1%) were discordant (not implemented), (95% confidence interval 11.1-20.0%). Looking at the reasons for discordance, 18 (43.9%) were due to co-morbid health issues, 14 (34.2%) related to patient choice and 8 (19.5%) decisions changed when more clinical information was available. For one discordant decision, the reason was not apparent. Discordant decisions were more frequent for patients with pancreatic or gastric carcinoma as compared to oesophageal cancer (P = 0.001). Results show that monitoring concordance between MDT decisions and final treatment implementation is useful to inform team decision-making. For upper gastrointestinal cancer, MDTs require more information about co morbid disease and patient choice to truly optimize the implementation of multi-disciplinary expertise.

Budesonide/formoterol and formoterol provide similar rapid relief in patients with acute asthma showing refractoriness to salbutamol

BACKGROUND

To compare the efficacy and safety of budesonide/formoterol (Symbicort) with formoterol (Oxis) in the treatment of patients with acute asthma who showed evidence of refractoriness to short-acting beta2-agonist therapy.

METHODS

In a 3 hour, randomized, double-blind study, a total of 115 patients with acute asthma (mean FEV1 40% of predicted normal) and a refractory response to salbutamol (mean reversibility 2% of predicted normal after inhalation of 400 microg), were randomized to receive either budesonide/formoterol (320/9 microg, 2 inhalations at t = -5 minutes and 2 inhalations at 0 minutes [total dose 1280/36 microg]) or formoterol (9 microg, 2 inhalations at t = -5 minutes and 2 inhalations at 0 minutes [total dose 36 microg]). The primary efficacy variable was the average FEV1 from the first intake of study medication to the measurement at 90 minutes. Secondary endpoints included changes in FEV1 at other timepoints and change in respiratory rate at 180 minutes. Treatment success, treatment failure and patient assessment of the effectiveness of the study medication were also measured.

RESULTS

FEV1 increased after administration of the study medication in both treatment groups. No statistically significant difference between the treatment groups was apparent for the primary outcome variable, or for any of the other efficacy endpoints. There were no statistically significant between-group differences for treatment success, treatment failure or patient assessment of medication effectiveness. Both treatments were well tolerated.

CONCLUSION

Budesonide/formoterol and formoterol provided similarly rapid relief of acute bronchoconstriction in patients with asthma who showed evidence of refractoriness to a short-acting beta2-agonist.

Predictors of outcome of mammography in the National Health Service Breast Screening Programme

BACKGROUND

Little is known about the factors influencing the risk of recall for assessment, invasive diagnostic procedures, and early rescreening after screening mammography.

METHODS

From June 1996 to March 1998 women attending screening at 10 National Health Service Breast Screening Programme (NHSBSP) centres completed a self administered questionnaire and were followed up for their screening outcome.

RESULTS

1969 (3.3%) out of 60 443 women aged 50-64 who had never used hormone replacement therapy (HRT) were recalled for assessment but were not diagnosed with breast cancer (defined here as false positive recall). After adjustment for the variation between centres, false positive recall was decreased significantly among women who were likely to have had a previous NHSBSP mammogram (odds ratio (OR) 0.49, 95% confidence interval (95% CI) 0.38 to 0.63 for likely versus unlikely), who were postmenopausal (OR 0.65, 95% CI 0.56 to 0.76 for postmenopausal v premenopausal) and increased significantly for women reporting previous breast surgery (OR 1.64, 95% CI 1.42 to 1.89). Although false positive recall decreased significantly with parity and increasing body mass index, these effects were not large and no significant variation was found with age, education, family history of breast cancer, oral contraceptive use, sterilisation, exercise, smoking, or alcohol consumption. Altogether 655 (1.1%) women had an invasive diagnostic procedure; no personal characteristics were predictive of this outcome, 286(0.5%) were referred for early rescreening, and this was increased significantly by nulliparity and a family history of breast cancer.

INTERPRETATION

Premenopausal women, those without a previous NHSBSP mammogram, and women with previous breast surgery have an increased risk of false positive recall by the NHSBSP.

A mammographic dilemma: calcification or haemosiderin as a cause of opacities? Validation of a new digital diagnostic tool

Core biopsies of an area of microcalcification demonstrated large collections of macrophages containing haemosiderin, with evidence of minimal microcalcification on H&E staining. Algorithms were developed that were capable of differentiating with high accuracy those signs due to calcification, using quantitative measurements such as the apparent volume composition of calcium. Using the linear attenuation coefficients of calcification and assuming an ellipsoid model for the 3-dimensional shape of calcification, we computed the relative calcification volume for each region of interest. The difference in the linear attenuation coefficients of iron and calcification allowed the two to be differentiated on a mammogram based on this measure of relative calcification volume.

Fixed implant rehabilitation of the edentulous maxilla: clinical guidelines and case reports. Part II

Fixed prosthetic implant reconstruction of the edentulous maxilla demands skill and state-of-the-art techniques of both the surgeon and the restorative dentist. As discussed in Part I (Implant Dent. 1999;8: 186-193), accurate diagnosis and treatment planning are essential to successful, predictable clinical results. How and where implants are placed have a lasting impact on the quality and prognosis of the final restoration. A series of clinical guidelines and considerations is reviewed with illustrative clinical treatment protocols of edentulous maxillae of unfavorable anatomy including attendant prosthetic difficulties. This article addresses the fixed implant rehabilitation of edentulous maxillas with inadequate posterior bone and favorable arch position, inadequate posterior bone and unfavorable arch position, and inadequate anterior and posterior bone and unfavorable arch position.

Three-dimensional reconstruction of microcalcification clusters from two mammographic views

Classification of benign/malignant microcalcification clusters is a major diagnostic challenge for radiologists. Clinical studies have revealed that the shape of the cluster, and the spatial distribution of individual microcalcifications within it, are important indicators of its malignancy. However, mammographic images of clustered microcalcifications confound their three-dimensional (3-D) distribution with image projection and breast compression. This paper presents a novel model-based method for reconstructing microcalcification clusters in 3-D from two mammographic views (cranio-caudal and medio-lateral oblique--"shoulder to the opposite hip" or lateral-medio). We develop a 3-D breast representation and a parameterised breast compression model which constraints geometrically the possible 3-D positions of a calcification in a two-dimensional image. Corresponding calcifications in the two views are matched using an estimate of the calcification volume. Both the geometric constraint and the matching criterion are utilized in the final reconstruction step to build the 3-D reconstructed clusters. Validation experiments are described using 30 clusters to verify the individual steps of the model, and results consistent with known ground truth are obtained. Some of the approximations in the model and future work are discussed in the concluding section.

Fixed implant rehabilitation of the edentulous maxilla: clinical guidelines and case reports. Part I

Fixed implant reconstruction is one of the most challenging prosthetic treatment alternatives for the edentulous maxilla. Accurate diagnosis and treatment planning are essential to successful, predictable clinical results. Decisions concerning the placement of implants may have a lasting impact on the quality and prognosis of the final restoration. A series of clinical guidelines and considerations is presented with illustrative clinical treatment protocols of edentulous maxillae that vary in degrees of anatomical and prosthetic difficulty. This article addresses the fixed implant rehabilitation of edentulous maxillas with favorable anatomy and favorable arch position, favorable anatomy, and unfavorable arch position, and unfavorable anatomy and favorable arch position.

Detecting film-screen artifacts in mammography using a model-based approach

Microcalcifications can be one of the earliest signs of breast cancer. Unfortunately, their appearance in mammograms can be mimicked by dust and dirt entering the imaging process and this has been shown previously to lead to false positives. We use a model of the imaging process and, in particular, the blurring functions inherent within it to detect the film-screen artifacts caused by dust and dirt and, thus, reduce false-positives. A crucial facet of the work is the choice of the correct image representation upon which to perform the image processing. After extensive testing, our algorithm has identified no microcalcifications as being artifacts and has an artifact detection rate of approaching 96%.

Taking on the student role: how can we improve the experience of registered nurses returning to study?

Regardless of the number of nurses who undertake graduate certificate courses in critical care nursing in Victoria, Australia, there is still a shortage of skilled nurses in the critical care areas. Preparation for practice in this specialist field has moved from hospital-based programs to tertiary-based courses during the past decade. As a consequence, there has been scrutiny of the clinical ability of graduates to perform the role function. Although this is understandable, anecdotal evidence to date indicates that students in these courses experience many difficulties, yet very little is written about the stressors they encounter. As the future of the critical care work force depends on a constant supply of students undertaking courses, it is essential to gain insight into the student experience, with a view to optimising it for future students and perhaps preventing attrition from courses. This paper describes a qualitative research study involving 14 students undertaking a graduate certificate course in critical care nursing. The aim of the study was to document the students' experience in relation to factors they identified as helping or hindering their progress on the course. Data were obtained at three points during the academic component of the course: on entry, at the end of semester 1 and at the end of semester 2. Interviews and questionnaires were used as the data collection methods. Results indicate that for this group of students, the experience of undertaking the course was adversely affected by stress related to three factors: change of role from clinician back to student; unmet expectations, and exhaustion. Recommendations related to preparation for study, curriculum timelines and peer support are included in this paper.

Horizontal transmission of feline immunodeficiency virus with semen from seropositive cats

The AIDS virus of cat species, feline immunodeficiency virus (FIV), has been used extensively as an animal model of HIV-1 infection. This felid lentivirus shares many molecular and biochemical traits with HIV-1 and causes similar immunologic and clinical perturbations, most notably CD4+ cell loss, impaired cell-mediated immunity and increased susceptibility to opportunistic pathogens. Previous reports have shown that FIV is transmitted horizontally by biting and vertically in utero and through nursing. Our objective was to determine whether FIV could be venereally transmitted in domestic cats. In the first experiment, susceptibility of the female reproductive tract to mucosal transmission of the FIV isolate, NCSU1, was demonstrated via intravaginal inoculation with infected cultured cells. We next identified virus in electroejaculates from asymptomatic, chronically FIV-NCSU1-infected, adult males. A fragment of FIV gag provirus DNA was detected by nested polymerase chain reaction (PCR) in nonfractionated seminal cells and in swim-up sperm preparations. Additionally, replication-competent virus was isolated from cell-free seminal plasma and seminal cells by co-cultivation with a feline CD4+ T-cell line. In the third study, queens were artificially inseminated via an intrauterine laparoscopic technique with electroejaculates from FIV-NCSU1-infected males. Of six inseminations carried out with fresh semen, three resulted in infection of queens. Lastly, immunohistochemical studies identified potential virus target cell populations in normal female reproductive tissues. In conclusion, these experiments indicate that FIV infection in domestic cats may provide a unique small animal model of sexual transmission of HIV-1.

Responses to time-varying stimuli in rat auditory cortex

Responses to frequency modulated (FM) sweeps were recorded in rat primary auditory cortex. Forty-four percent of the cells were direction-selective. For speed selectivity, the majority of the cells preferred faster sweeps. The results suggest that rat auditory cortex may be used for processing communication signals of their predators or for detecting spectral changes in acoustic signals.

Effect on attendance at breast cancer screening of adding a self administered questionnaire to the usual invitation to breast screening in southern England

STUDY OBJECTIVE

The primary aim of the research described in this paper was to ascertain whether inclusion of a self administered questionnaire with the usual invitation to routine breast screening affected screening uptake. Secondary aims included establishing appropriate questionnaire distribution and collection methods within the framework of the National Health Service Breast Screening Programme and optimisation of questionnaire design.

DESIGN

Randomised study.

SETTING

Oxfordshire and West of London Breast Screening Units.

PARTICIPANTS/METHODS

6400 women invited for routine screening mammography were individually randomised to receive either the usual breast screening invitation alone, or to receive the usual invitation accompanied by a self administered questionnaire, to be returned at the time of screening. Participants were then followed up and attendance rates at screening were compared between groups.

MAIN RESULTS

Screening attendance rates were similar in women who did and did not receive a questionnaire (71% in each group). Of those who were sent a questionnaire and attended for screening, 77% returned a completed questionnaire. Screening uptake was not affected by the way in which the questionnaire was returned or by whether or not personal details and signed permission for follow up were requested.

CONCLUSIONS

The inclusion of a self administered questionnaire accompanying the invitation to breast screening did not adversely affect screening uptake. A high proportion of women completed the questionnaire.

Cortical cell loss in asymptomatic cats experimentally infected with feline immunodeficiency virus

Specific pathogen-free cats experimentally infected with feline immunodeficiency virus (FIV) were used to evaluate the development of central nervous system changes during the asymptomatic stages of viral infection. The brains of asyptomatic cats were examined at postinoculation times ranging from 8 weeks to 3 years for changes in neuron density, glutamate receptor density, and synaptophysin immunoreactivity. At 2-3 years postinoculation a small decrease in neuronal density was found in layers 2-3 and layer 5 of the frontal cortex (-14.4%), parietal cortex (-18.1%), and striatum (-29.5%). The only other indications of pathology within these regions were a mild diffuse astrogliosis, occasional microglial nodules, and the accumulation of satellite cells around selected neurons. An average loss of large neurons of 56-68% was seen in the cortex of four random source cats euthanized with AIDS. These values contrasted with the absence of any significant cell loss in FIV-infected cats 18 weeks after inoculation or FIV-negative controls. The loss of neurons in the asymptomatic cats showed a significant positive correlation with a decrease in the blood CD4:CD8 ratios. Morphometric evaluation of synaptic terminal densities immunocytochemically stained with synaptophysin revealed a significant increase in the asymptomatic cats at 2-3 years postinoculation that correlated negatively with the CD4:CD8 ratios. Random source AIDS cats showed a 34% decrease in synaptophysin-immunoreactive profiles. Glutamate binding in the cortex did not change significantly in the asymptomatic cats (4-7% decline). Thus, experimentally infected specific pathogen-free cats show a loss of cortical neurons similar to what has been observed in postmortem studies of humans infected with HIV. The detection of neuronal loss during the asymptomatic stage of disease and the correlation with the peripheral CD4:CD8 cell ratios indicate that neurodegeneration may progress in parallel with peripheral disease.

Women doctors' use of hormone replacement therapy. High prevalence of use is not confined to doctors

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Enhanced expression of novel CD57+CD8+ LAK cells from cats infected with feline immunodeficiency virus

As a model for lymphokine-activated killer (LAK) function in HIV infection, we studied LAK cells in cats infected with feline immunodeficiency virus (FIV), which causes an acquired immunodeficiency syndrome. Peripheral blood mononuclear cells cultured in concanavalin A and interleukin-2 developed LAK cytotoxicity against chronically FIV-infected CrFK cells and acutely infected CD4+ lymphocytes but not uninfected cells. LAK cells from FIV+ cats were more cytotoxic than LAK cells from uninfected cats. Enhanced FIV+ LAK cytotoxicity against feline leukemia virus-infected cells (FL74) suggested that the cytotoxicity was not antigen specific. Two-color fluorescence-activated cell sorter analysis and antibody depletion studies demonstrated that the majority of LAK cells and their progenitors were positive for both CD8 and CD57. The in vitro induction of dual positive CD8+CD57+ LAK cells was enhanced in FIV+ cats, as reported for HIV+ patients. These CD8+CD57+ LAK cells may play a role in maintaining the long asymptomatic stage of infection in FIV+ cats.

Therapeutic effects of diethylcarbamazine and 3'-azido-3'-deoxythymidine on feline leukemia virus lymphoma formation

Twenty-four specific pathogen-free kittens were infected with the Rickard strain of feline leukemia virus (FeLVR). The kittens were divided into four equal groups and were orally administered either a high dose of diethylcarbamazine (DECH, 12 mg kg-1), a low dose of diethylcarbamazine (DECL, 3 mg kg-1), 3'-azido-3'-deoxythymidine (AZT, 15 mg kg-1, b.i.d.), or a placebo (250 mg granular dextrose) daily for 10 weeks. Blood was collected at 2-week intervals for complete blood counts (CBC) and flow cytometric analysis (FACS) of peripheral blood lymphocytes (PBL). Plasma was assayed for antibodies to FeLV gp70 and for FeLV p27 antigen using ELISA assays. For FACS analysis, lymphocytes were incubated with monoclonal antibodies to feline Pan T, CD8+, CD4+, and B cell (Anti-Ig) antigens. In the placebo treated cats, FeLVR infection caused an early (2 weeks p.i.) and persistent decrease in leukocyte numbers attributable primarily to a decrease in neutrophil numbers and a secondary lesser decrease in B and CD4+ lymphocyte numbers. The DEC-treated groups showed a delayed but similar leukopenia by 4 weeks p.i. The lymphopenia in the DEC groups (primarily B cells and CD4+ cells) was reversed by 10 weeks p.i., but the neutropenia persisted. AZT treatment inhibited FeLVR-induced lymphopenia but did not prevent a reduction in neutrophil numbers. A marked p27 antigenemia that peaked at 4 weeks p.i. was noted in the placebo treated cats and in most cats (11/12) treated with either dose of DEC. However, AZT significantly inhibited the p27 antigenemia and all cats were negative for p27 antigen between 6 and 10 weeks of treatment. In general, placebo treated cats as well as DECH and DECL cats had low levels of antibody to gp70 throughout the study, suggesting FeLVR-induced immunosuppression. In contrast, significantly higher titers of anti-gp70 antibodies were seen in AZT-treated cats at 6 weeks p.i., and were maintained throughout treatment. Eighteen month survival rates provide efficacy data for AZT as well as both DEC treatment groups. While all placebo treated cats were euthanized by 52 weeks p.i. due to FeLV associated lymphomas with a mean survival time of 35.5 weeks p.i., median survival time of the AZT treated group was > or = 102 weeks p.i., while that of the DECH and DECL groups was 69.7 and 72 weeks p.i., respectively. Thus, DEC as well as AZT therapy delays the development of lymphomas associated with FeLV infection and significantly improves survival.

Chin bone harvesting for autogenous grafting in the maxillary sinus: a clinical report

The sinus lift has become a common dental procedure when insufficient bone exists to support endosseous dental implants. The goal of the procedure is to augment existing bone in the posterior maxilla. Various resorbable and nonresorbable allograft, xenograft, and synthetic materials and mixtures, with and without autogenous bone, have been used for sinus augmentation. The authors prefer a mixture of autogenous bone with resorbable bovine xenograft, utilizing as much autogenous bone as possible. The chin offers an ideal site for bone harvesting because of its advantages over other potential sites, such as iliac crest, rib, and calvarium. These advantages include ease of accessibility, relatively simple office-based surgery, minimal morbidity, and the benefits of utilizing intramembranous versus endochondral bone. This article describes the harvesting and the sinus lift procedures. The learning objective of this article is to present this particular procedure using a clinical report to illustrate.

Achieving implant reconstruction through bilateral mandibular nerve repositioning

Grafting is one treatment option for patients who have insufficient bone for implant placement. However, repositioning the neurovascular bundle also can allow for placement of endosseous implants. This case illustrates bilateral repositioning of the mandibular nerves and subsequent implant placement.

Herpes simplex hepatitis in a patient with psoriatic arthritis taking prednisone and methotrexate. Report and review of the literature

Herpes simplex hepatitis is a rare disease in adults and with high mortality (81%). Most cases are seen in immunocompromised hosts or in the third trimester of pregnancy. A 43-year-old woman with psoriatic arthritis, treated with prednisone and methotrexate (MTX), presented with an acute abdomen and elevated liver enzymes. The diagnosis was made by liver biopsy. MTX was stopped and acyclovir was started. The patient survived. The diagnosis of Herpes simplex should be suspected in immunocompromised hosts and established by liver biopsy and viral cultures. Treatment includes parenteral acyclovir and discontinuation or reduction of immunosuppressive therapy.

Detection of periodontal disease activity with a scintillation camera

The goal of this study was to assess the ability of a scintillation camera method to detect areas of active bone loss due to periodontitis. Technetium 99m methylene diphosphonate was used as the bone-seeking radiopharmaceutical. Bone-seeking radiopharmaceutical uptake (BSRU) was imaged and quantified in alveolar bone regions of interest with a scintillation camera and a computer. Analysis of the sequential radiographs over six months constituted the basis for determination of sites of active disease. The study was composed of two parts. First, 18 subjects, nine with adult periodontitis and nine controls, were enrolled in a cross-sectional study to determine whether the quantitative scintillation amera methodology detected differences in BSRU in periodontitis vs. periodontally healthy patients. Second, the nine patients with periodontitis were studied longitudinally in order to determine whether the BSRU examination was indicative of bone loss subsequently measured radiographically. In the cross-sectional study, the mean uptake ratio for the periodontitis group was significantly higher than that for the control group (1.63 +/- 0.06 and 1.42 +/- 0.04, respectively, p less than 0.01, t test). From the longitudinal study, the mean patient scintillation image uptake ratios were highly correlated with the mean bone loss determined from serial radiographs (p less than 0.01). The accuracy, sensitivity, and specificity of the quantitative gamma camera method for detecting site(s) of active bone loss within the region of interest were assessed relative to the longitudinal radiographic data. The accuracy, sensitivity, and specificity were 85%, 90%, and 79%, respectively. Alveolar bone scintigraphy with a gamma camera and computer may provide a simple and valid technique for the immediate indication of areas of periodontal disease activity.

Human recombinant interleukin-2 induces maturation and activation signals for feline eosinophils in vivo

Immunotherapy, with interleukin-2 (IL-2) or IL-2 plus lymphokine-activated killer (LAK) cells, has been used to treat cancer and acquired immunodeficiency syndrome (AIDS) in man. Similarities between feline leukemia virus (FeLV) infection in the cat and human immunodeficiency virus (HIV) infection in man have prompted immunotherapeutic studies in the cat. To develop baseline data on hematological responses to infused IL-2, cats were given daily (1-14 days) i.v. injections of 5 x 10(4) U/kg of recombinant human IL-2 (rHulL-2). Complete blood cell (CBC) counts were done weekly. Red blood cell (RBC), neutrophil, and lymphocyte numbers did not change appreciably over the course of the study. In contrast, rHulL-2 caused an eosinophilia in all but the 1 day treatment group. Treatment for 3 days generated a transient eosinophilia on day 7 that returned to baseline by 3 weeks. Five day and 7 day treatments generated an eosinophilia by day 7 that peaked on day 14 and returned to normal values by day 28. Treatment of cats for 14 days did not increase the magnitude or duration of the eosinophilia beyond the 5 or 7 day treatments. Bone marrow (BM) biopsies from rHulL-2-treated cats revealed a marked selective hyperplasia of eosinophil precursors. In the 5 day treatment group, all maturation stages of eosinophils were elevated by week 1 of treatment. By week 2, the early stages had returned to normal, whereas the late stage cells remained elevated, suggesting an ordered maturation response. Numbers of all eosinophil precursors approximated pretreatment numbers by weeks 3-4. Thus the BM hyperplasia preceded the blood eosinophilia by 1 week, suggesting that an enhanced maturation response of BM eosinophil precursors is a major contributor to the rHulL-2-induced blood eosinophilia. In addition to a maturation signal, rHulL-2 induces a potent activation signal for eosinophils as measured by a decrease in density and an increase in longevity in culture. The significance of the activated eosinophil in the therapeutic or toxicologic response to rHulL-2 infusion is discussed.

Osteosarcoma--presumed lymph node metastases in two cases

Two patients with osteosarcoma of a lower limb and presumed lymph node metastases are described. The metastases presented in both children as palpable masses, one in the inguinal region and the other in the pelvis. One was visible on plain radiography; both were demonstrated on computed tomography and bone scintigraphy. The inguinal mass was present at the first examination and was resected with the primary lesion. The pelvic mass presented 12 months after amputation and was unresectable; its subsequent rapid growth was demonstrated by computed tomography. In one patient the osteosarcoma was of the osteoblastic type.

Five patients with Rasmussen's syndrome investigated by single-photon-emission computed tomography

Five patients with Rasmussen's syndrome (sometimes known as smouldering encephalitis), are presented. This rare form of childhood epilepsy is characterized by intractable partial seizures with progressive neurological and mental impairment. Diagnostic brain biopsy shows the histological changes of active encephalitis, consistent with a viral infection. Although the raised cerebrospinal fluid (CSF) complement and interferon levels seen in some patients support this hypothesis, no infective agent has yet been isolated. All five patients were investigated by transmission computed tomography (CT) of the head, electroencephalography (EEG) and cerebral single-photon-emission computed tomography (SPECT) using 99Tcm-hexamethylpropylenamine oxime (HMPAO) and in addition 123I-amphetamine (IMP) in Patient 1. 99Tcm-HMPAO is now regarded as reflecting cerebral perfusion, whereas the uptake of 123I-amphetamine is more dependent on cell function. In all patients SPECT imaging demonstrated an area of hypoperfusion/hypometabolism which corresponded to the anatomical localization of the epiletogenic foci found by clinical assessment, EEG and CT. In all cases the SPECT study also demonstrated a more extensive area of abnormality than CT, and in the two patients who had sequential studies, alteration in the size of the defect was found which correlated with the patients' changing clinical condition. SPECT imaging in Rasmussen's syndrome may facilitate anatomical localization of the area of pathology, and may demonstrate a changing pattern in cerebral hypoperfusion/hypometabolism. It could also serve as a guide to accurate brain biopsy.

Viral encephalitis: imaging with SPECT

SPECT brain imaging performed in two patients with presumed herpes encephalitis demonstrated greater sensitivity and more precise localization than either planar brain imaging or CT scanning.

Single photon emission computed tomography in Alzheimer's disease. Abnormal iofetamine I 123 uptake reflects dementia severity

To determine whether abnormalities in regional cerebral functional activity estimated by iofetamine hydrochloride I 123 and single photon emission computed tomography can be detected in mild or moderate as well as severe cases of Alzheimer's disease (AD), we performed iofetamine I 123-single photon emission computed tomography in 37 patients with probable AD (nine patients with mild, 18 patients with moderate, and ten patients with severe dementia) and nine age-matched control subjects. Iofetamine I 123 uptake was measured in right and left frontal, temporal, parietal, and occipital cortices. Mean (right and left) iofetamine I 123 activity was lowest in the parietal region of patients with AD and was significantly reduced in the other three regions compared with control subjects. Only in the parietal region was lower relative iofetamine I 123 activity associated with an impaired level of patient function and with cognitive deficit.

Metacarpophalangeal arthropathy associated with manual labor (Missouri metacarpal syndrome). Clinical radiographic, and pathologic characteristics of an unusual degeneration process

We describe 7 manual laborers with painful, palpably enlarged metacarpophalangeal joints. Characteristic radiographic changes were joint space loss, prominent osteophytes, and cystic metacarpal heads most prominent in the second and third metacarpophalangeal joints. In 3 of 4 patients, joint biopsy specimens showed subsynovial fibrosis and villous hyperplasia. All 7 patients had similar backgrounds of heavy work demanding sustained gripping motions of both hands, for periods that exceeded 30 years. We designated their condition metacarpophalangeal arthropathy associated with manual labor.