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1.
Breast Cancer Res ; 24(1): 55, 2022 07 30.
Article in English | MEDLINE | ID: mdl-35907862

ABSTRACT

BACKGROUND: Abbreviated breast MRI (abMRI) is being introduced in breast screening trials and clinical practice, particularly for women with dense breasts. Upscaling abMRI provision requires the workforce of mammogram readers to learn to effectively interpret abMRI. The purpose of this study was to examine the diagnostic accuracy of mammogram readers to interpret abMRI after a single day of standardised small-group training and to compare diagnostic performance of mammogram readers experienced in full-protocol breast MRI (fpMRI) interpretation (Group 1) with that of those without fpMRI interpretation experience (Group 2). METHODS: Mammogram readers were recruited from six NHS Breast Screening Programme sites. Small-group hands-on workstation training was provided, with subsequent prospective, independent, blinded interpretation of an enriched dataset with known outcome. A simplified form of abMRI (first post-contrast subtracted images (FAST MRI), displayed as maximum-intensity projection (MIP) and subtracted slice stack) was used. Per-breast and per-lesion diagnostic accuracy analysis was undertaken, with comparison across groups, and double-reading simulation of a consecutive screening subset. RESULTS: 37 readers (Group 1: 17, Group 2: 20) completed the reading task of 125 scans (250 breasts) (total = 9250 reads). Overall sensitivity was 86% (95% confidence interval (CI) 84-87%; 1776/2072) and specificity 86% (95%CI 85-86%; 6140/7178). Group 1 showed significantly higher sensitivity (843/952; 89%; 95%CI 86-91%) and higher specificity (2957/3298; 90%; 95%CI 89-91%) than Group 2 (sensitivity = 83%; 95%CI 81-85% (933/1120) p < 0.0001; specificity = 82%; 95%CI 81-83% (3183/3880) p < 0.0001). Inter-reader agreement was higher for Group 1 (kappa = 0.73; 95%CI 0.68-0.79) than for Group 2 (kappa = 0.51; 95%CI 0.45-0.56). Specificity improved for Group 2, from the first 55 cases (81%) to the remaining 70 (83%) (p = 0.02) but not for Group 1 (90-89% p = 0.44), whereas sensitivity remained consistent for both Group 1 (88-89%) and Group 2 (83-84%). CONCLUSIONS: Single-day abMRI interpretation training for mammogram readers achieved an overall diagnostic performance within benchmarks published for fpMRI but was insufficient for diagnostic accuracy of mammogram readers new to breast MRI to match that of experienced fpMRI readers. Novice MRI reader performance improved during the reading task, suggesting that additional training could further narrow this performance gap.


Subject(s)
Breast Neoplasms , Breast/diagnostic imaging , Breast Neoplasms/diagnostic imaging , Female , Humans , Magnetic Resonance Imaging/methods , Mammography/methods , Prospective Studies , Sensitivity and Specificity
2.
ACS Appl Mater Interfaces ; 12(23): 26525-26533, 2020 Jun 10.
Article in English | MEDLINE | ID: mdl-32321237

ABSTRACT

The simultaneous imaging of magnetic fields and temperature (MT) is important in a range of applications, including studies of carrier transport and semiconductor device characterization. Techniques exist for separately measuring temperature (e.g., infrared (IR) microscopy, micro-Raman spectroscopy, and thermo-reflectance microscopy) and magnetic fields (e.g., scanning probe magnetic force microscopy and superconducting quantum interference devices). However, these techniques cannot measure magnetic fields and temperature simultaneously. Here, we use the exceptional temperature and magnetic field sensitivity of nitrogen vacancy (NV) spins in conformally coated nanodiamonds to realize simultaneous wide-field MT imaging at the device level. Our "quantum conformally attached thermo-magnetic" (Q-CAT) imaging enables (i) wide-field, high-frame rate imaging (100-1000 Hz); (ii) high sensitivity; and (iii) compatibility with standard microscopes. We apply this technique to study the industrially important problem of characterizing multifinger gallium nitride high-electron mobility transistors (GaN HEMTs). We spatially and temporally resolve the electric current distribution and resulting temperature rise, elucidating functional device behavior at the microscopic level. The general applicability of Q-CAT imaging serves as an important tool for understanding complex MT phenomena in material science, device physics, and related fields.

3.
Br J Radiol ; 92(1104): 20190663, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31559859

ABSTRACT

OBJECTIVES: To assess whether NHS breast screening programme (NHSBSP) mammogram readers could effectively interpret first post-contrast acquisition subtracted (FAST) MRI, for intended use in screening for breast cancer. METHODS: Eight NHSBSP mammogram readers from a single centre (four who also read breast MRI (Group 1) and four who do not (Group 2)) were given structured FAST MRI reader training (median 4 h: 32 min). They then prospectively interpreted 125 FAST MRIs (250 breasts: 194 normal and 56 cancer) comprising a consecutive series of screening MRIs enriched with additional cancer cases from 2015, providing 2000 interpretations. Readers were blinded to other readers' opinions and to clinical information. Categorisation followed the NHSBSP MRI reporting categorisation, with categories 4 and 5 considered indicative of cancer. Diagnostic accuracy (reference standard: histology or 2 years' follow-up) and agreement between readers were determined. RESULTS: The accuracy achieved by Group 2 (847/1000 (85%; 95% confidence interval (CI) 82-87%)) was 5% less than that of Group 1 (898/1000 (90%; 95% CI 88-92)). Good inter-reader agreement was seen between both Group 1 readers (κ = 0.66; 95% CI 0.61-0.71) and Group 2 readers (κ = 0.63; 95% CI 0.58-0.68). The median time taken to interpret each FAST MRI was Group 1: 34 s (range 3-351) and Group 2: 77 s (range 11-321). CONCLUSION: Brief structured training enabled multiprofessional mammogram readers to achieve similar accuracy at FAST MRI interpretation to consultant radiologists experienced at breast MRI interpretation. ADVANCES IN KNOWLEDGE: FAST MRI could be feasible from a training-the-workforce perspective for screening within NHSBSP.


Subject(s)
Breast Neoplasms/diagnostic imaging , Breast/diagnostic imaging , Data Accuracy , Magnetic Resonance Imaging/methods , Mammography , Radiologists/education , Confidence Intervals , Contrast Media , Female , Humans , Prospective Studies , Reference Standards , Sensitivity and Specificity , Time Factors
4.
Article in English | MEDLINE | ID: mdl-29075507

ABSTRACT

BACKGROUND: Skin tears are common in older adults and those taking steroids and warfarin. They are traumatic, often blunt injuries caused by oblique knocks to the extremities. The epidermis may separate from the dermis or both layers from underlying tissues leaving a skin flap or total loss of tissue, which is painful and prone to infection. 'Dermatuff™' knee-length socks containing Kevlar fibres (used in stab-proof vests and motorcyclists' clothing) aim to prevent skin tears. The acceptability of the socks and the feasibility of a randomised controlled trial (RCT) had not been explored. METHODS: In this pilot parallel group RCT, 90 people at risk of skin-tear injury from Devon care homes and primary care were randomised to receive the socks or treatment as usual (TAU). The pilot aimed to estimate parameters to inform the design of a substantive trial and record professionals' views and participants' acceptability of the intervention and of study participation. RESULTS: Participants were randomised from July 2013 and followed up until February 2015. Community participants were easier to recruit than care homes residents but were 10 years younger on average and more active. To recruit 90 participants, 395 had to be approached overall as 77% were excluded or declined. Seventy-nine participants (88%) completed the trial and 27/44 (61%) wore the socks for 16 weeks. There were 31 skin tear injuries affecting 18 (20%) of the 90 participants. The TAU group received more injuries, more repeated episodes, and larger tears with greater severity. Common daily diary reasons for not wearing the socks included perceived warmth in hot weather or not being available (holiday, in hospital, bed rest). Resource use data were obtainable and indicated that sock wearing gave a reduction in treatment costs whilst well-completed questionnaires showed improvements in secondary outcomes. CONCLUSIONS: This pilot trial has successfully informed the design and conduct of a future definitive cost-effectiveness RCT. It would need to be conducted in primary care with 880 active at-risk, elderly patients (440 per arm). Skin tear incidence and quality of life (from EQ5D5L) over a 4-month period would be the primary and secondary outcomes respectively. TRIAL REGISTRATION: ISRCTN, ISRCTN96565376.

5.
Article in English | MEDLINE | ID: mdl-27965791

ABSTRACT

BACKGROUND: Skin tears are traumatic injuries occurring mostly on the extremities due to shearing and friction forces that separate the epidermis and the dermis from underlying tissues. They are common and occur mostly in older adults and those taking medications that compromise skin integrity. Pretibial skin tears can develop into leg ulcers, which require lengthy, expensive treatment to heal. Traumatic injuries are the second most common type of wounds after pressure ulcers in care homes and are the commonest reason for older adults to require the attention of a community nurse. Common causes of skin tear injuries are bumping into furniture and other obstacles, using mobility aids, transfer to/from wheelchairs, getting in and out of bed and falls. No effective preventative measures currently exist but knee-length, protective socks are now available that contain impact-resistant Kevlar fibres (of the type used in stab-proof vests) and cushioning layers underneath. METHODS/DESIGN: In this pilot parallel group, randomised controlled trial, 90 people at risk of skin-tear injury will be randomised with equal allocation to receive the intervention or usual care. They will be recruited from care homes and from the community via general practices and a research volunteer database. Pilot outcomes include recruitment, eligibility, attrition, ascertainment of injuries and completion of outcome measures. Acceptability of the intervention and of study participation will be explored using semi-structured interviews. The proposed primary outcome for the future definitive trial is skin tear-free days. Secondary outcomes are skin tear severity, health status, specific skin-tears quality of life, capability and fear of falling, measured at baseline and the end of the study and in the event of a skin tear. DISCUSSION: The results of this study will be used to inform the development and design of a future randomised controlled trial to assess the effectiveness and cost-effectiveness of a unique and innovative approach to skin tear prevention. Approval was granted by the NRES - Cornwall and Plymouth Research Ethics Committee (13/SW/013). Dissemination will include publication of quantitative and qualitative findings, and experience of public involvement in peer-reviewed journals. TRIAL REGISTRATION: Current Controlled Trials: ISRCTN96565376.

6.
Surg Endosc ; 26(12): 3616-21, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22733191

ABSTRACT

BACKGROUND: Magnetic endoscopic imagers (MEIs) are being introduced during colonoscopy, principally for training. They aid recognition and resolution of loops. This has potential to improve technique resulting in increased completion rates and better patients' experience. OBJECTIVE: To determine whether the use of a MEI improves colonoscopists' performance. DESIGN: Cohort study. SETTINGS: Endoscopy unit in a district general hospital. PATIENTS: Consecutive patients undergoing colonoscopy during a 33 month period were studied. INTERVENTION: Patients underwent colonoscopy with or without the use of a magnetic endoscopic imager. MAIN OUTCOME MEASURES: Patient comfort and colonoscopy completion rates with and without the use of a magnetic endoscopic imager. Other data recorded included sedation and analgesia doses, patient age and gender, bowel preparation quality, antispasmodic dose, time of day, and consciousness level. RESULTS: A total of 5,879 colonoscopies were performed. A magnetic endoscopic imager was used for 4,873. A greater proportion of patients in the imager group had the lowest discomfort score (56.2 vs. 39.8%, logistic regression; p = 0.005). Doses of midazolam were similar in both groups (1.93 vs. 2.14 mg for imager and nonimager groups respectively). Completion rates were 94.5% with an imager and 91% without (logistic regression; p = 0.088). Logistic regression analysis showed that buscopan improved completion rate but detrimental factors included increasing patient age, discomfort, poor bowel preparation, and an afternoon procedure. Factors not influencing completion included gender, sedation and analgesia doses, and consciousness level. There was no correlation between documented reason for failure and use of the imager. LIMITATIONS: This was a nonrandomized trial although improved with logistic regression analysis. CONCLUSIONS: Magnetic endoscopic imager use improves patient comfort during colonoscopy but has not been shown to improve completion.


Subject(s)
Colonoscopy/standards , Diagnostic Imaging/instrumentation , Intraoperative Care/instrumentation , Cohort Studies , Female , Humans , Magnetic Phenomena , Male , Middle Aged , Prospective Studies
7.
Menopause Int ; 16(2): 56-9, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20729494

ABSTRACT

OBJECTIVE: To test the hypothesis that premenopausal hysterectomy compromises ovarian function and accelerates ovarian failure. DESIGN: Longitudinal prospective cohort study. Annual follow-up with serum follicle-stimulating hormone levels with all women being 46 years of age or less at the time of hysterectomy for benign disease. SETTING: Gloucestershire Royal Hospital, Gloucester, UK. PARTICIPANTS: Five hundred and thirty-one women recruited over a four-year period from 1994 to 1997. RESULTS: The median age of women in the study was 37 (range 22-46). Women had earlier ovarian failure after unilateral oophorectomy (hazard ratio 2.41, 95% confidence interval (CI) 1.44-4.04) and after vaginal hysterectomy (hazard ratio 2.04, 95% CI 1.33-3.14) compared with abdominal hysterectomy. The mean age of ovarian failure across all groups was 45.87 (+/-3.58), and 59 (11%) women remained in the study at the end of 10 years who had not yet entered the menopause. CONCLUSION: This is the largest number of cases collected prospectively looking at ovarian failure after hysterectomy. Earlier ovarian failure occurred in those women having unilateral oophorectomy or vaginal hysterectomy. Early ovarian failure was not confirmed across the study group with only 2% of women having confirmed ovarian failure by Kaplan-Meier estimate one year after surgery and 14% at five years.


Subject(s)
Hysterectomy/adverse effects , Premenopause , Primary Ovarian Insufficiency/epidemiology , Primary Ovarian Insufficiency/etiology , Adult , Age Factors , Female , Follicle Stimulating Hormone/blood , Humans , Hysterectomy/methods , Longitudinal Studies , Menopause/blood , Middle Aged , Prospective Studies , United Kingdom/epidemiology , Young Adult
8.
Menopause Int ; 16(2): 60-4, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20729495

ABSTRACT

OBJECTIVE: To quantify compliance with using estrogen-only hormone replacement therapy (HRT) up until the time of mean age of natural menopause in women undergoing either bilateral oophorectomy or removal of one remaining ovary at the time of hysterectomy for benign disease. DESIGN: Prospective study. Annual questionnaire follow-up for ten years of women undergoing hysterectomy and bilateral oophorectomy for benign disease aged 46 or less at the time of surgery. SETTING: Gloucestershire Royal Hospital. PARTICIPANTS: Five hundred and twenty-one women recruited over a four-year period from 1994 to 1997. MAIN OUTCOME MEASURES: Compliance with HRT use, changes in HRT preparations and reasons for discontinuation. RESULTS: The median age of women at the time of hysterectomy was 42 (range 22-46) years; 4.9% (n = 24) stopped HRT within the first two years and 16.5% (n = 86) by the end of the study. The majority of women were prescribed HRT tablets (253, 48%) and the next most common being patches. In total, there were 1271 episodes of changing HRT, with the range between 0 and 18 changes per woman over the ten-year period. In all, 32% of changes were to a different route of HRT, 19% were to a different preparation of the same route, 18% were to an increased dose of the same preparation and 7% were to a decreased dose of the same preparation. CONCLUSIONS: Compliance with HRT use was high throughout the study, although responses decreased after five years. Change to HRT preparations was consistently high across all preparations. Women requiring HRT after surgical menopause need to be supported in finding the right preparation for them.


Subject(s)
Estrogen Replacement Therapy , Medication Adherence , Menopause, Premature , Ovariectomy/adverse effects , Adult , Female , Follow-Up Studies , Humans , Middle Aged , Prospective Studies , Surveys and Questionnaires , Young Adult
9.
Fam Pract ; 25(5): 328-33, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18687983

ABSTRACT

BACKGROUND: Polymyalgia rheumatica (PMR) is common and is usually diagnosed and managed in primary care. There are no generally accepted primary care criteria for diagnosis. OBJECTIVES: To identify what features are used to diagnose PMR, to benchmark these against diagnostic criteria and to identify features at diagnosis with prognostic significance. METHODS: This was a retrospective cohort study of all patients diagnosed with PMR in three UK general practices between January 1994 and December 2003. The medical records were examined for features of PMR. The duration of steroid treatment was used as a proxy for duration of disease. Analysis of prognostic predictors was by Cox proportional hazards models. RESULTS: One hundred and eighty-three patients were identified, giving an overall annual incidence of 11.3 per 10 000 patients aged 50 or over. The median age at diagnosis was 75 (interquartile range 69, 79) years: 138 (75%) were female. The most common diagnostic features were proximal muscle pain in 151 (82%), raised inflammatory markers in 160 (87%), clinical response to corticosteroids in 166 (91%) and normalization of inflammatory markers in 147 (81%). Twenty (11%) had normal inflammatory indices. The median duration of treatment was 1.4 years (interquartile range 0.8, 2.4). Female sex and raised inflammatory markers were independently associated with longer treatment: female hazard ratio 1.5 (1.0, 2.2) P = 0.047 and raised inflammatory markers 2.0 (1.2, 3.2) P = 0.01. CONCLUSIONS: Primary care practitioners do not use established criteria to diagnose PMR and sometimes diagnose the condition even when inflammatory markers are normal. This exposes patients to a risk of inappropriate steroid use.


Subject(s)
Outcome Assessment, Health Care , Polymyalgia Rheumatica/diagnosis , Polymyalgia Rheumatica/drug therapy , Primary Health Care , Aged , Cohort Studies , Female , Humans , Male , Middle Aged , Polymyalgia Rheumatica/physiopathology , Retrospective Studies , United Kingdom
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