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2.
Eur J Radiol ; 167: 111087, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37690352

RESUMO

Accumulating evidence from retrospective studies demonstrate at least non-inferior performance when using AI algorithms with different strategies versus double-reading in mammography screening. In addition, AI algorithms for mammography screening can reduce work load by moving to single human reading. Prospective trials are essential to avoid unintended adverse consequences before incorporation of AI algorithms into UK's National Health Service (NHS) Breast Screening Programme (BSP). A stakeholders' meeting was organized in Newnham College, Cambridge, UK to undertake a review of the current evidence to enable consensus discussion on next steps required before implementation into a screening programme. It was concluded that a multicentre multivendor testing platform study with opt-out consent is preferred. AI thresholds from different vendors should be determined while maintaining non-inferior screening performance results, particularly ensuring recall rates are not increased. Automatic recall of cases using an agreed high sensitivity AI score versus automatic rule out with a low AI score set at a high sensitivity could be used. A human reader should still be involved in decision making with AI-only recalls requiring human arbitration. Standalone AI algorithms used without prompting maintain unbiased screening reading performance, but reading with prompts should be tested prospectively and ideally provided for arbitration.


Assuntos
Neoplasias da Mama , Detecção Precoce de Câncer , Humanos , Feminino , Inteligência Artificial , Neoplasias da Mama/diagnóstico por imagem , Estudos Prospectivos , Estudos Retrospectivos , Medicina Estatal , Algoritmos
3.
Clin Radiol ; 76(10): 763-773, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33820637

RESUMO

In the UK, women between 50-70 years are invited for 3-yearly mammography screening irrespective of their likelihood of developing breast cancer. The only risk adaption is for women with >30% lifetime risk who are offered annual magnetic resonance imaging (MRI) and mammography, and annual mammography for some moderate-risk women. Using questionnaires, breast density, and polygenic risk scores, it is possible to stratify the population into the lowest 20% risk, who will develop <4% of cancers and the top 4%, who will develop 18% of cancers. Mammography is a good screening test but has low sensitivity of 60% in the 9% of women with the highest category of breast density (BIRADS D) who have a 2.5- to fourfold breast cancer risk. There is evidence that adding ultrasound to the screening mammogram can increase the cancer detection rate and reduce advanced stage interval and next round cancers. Similarly, alternative tests such as contrast-enhanced mammography (CESM) or abbreviated MRI (ABB-MRI) are much more effective in detecting cancer in women with dense breasts. Scintimammography has been shown to be a viable alternative for dense breasts or for follow-up in those with a personal history of breast cancer and scarring as result of treatment. For supplemental screening to be worthwhile in these women, new technologies need to reduce the number of stage II cancers and be cost effective when tested in large scale trials. This article reviews the evidence for supplemental imaging and examines whether a risk-stratified approach is feasible.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Diagnóstico por Imagem/métodos , Detecção Precoce de Câncer/métodos , Mama/diagnóstico por imagem , Feminino , Humanos , Risco
4.
Eur J Neurol ; 28(2): 587-594, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33058438

RESUMO

BACKGROUND: A randomized trial of phenytoin in acute optic neuritis (ON) demonstrated a 30% reduction in retinal nerve fiber layer (RNFL) loss with phenytoin versus placebo. Here we present the corresponding serum neurofilament analyses. METHODS: Eighty-six acute ON cases were randomized to receive phenytoin (4-6 mg/kg/day) or placebo for 3 months, and followed up for 6 months. Serum was collected at baseline, 3 and 6 months for analysis of neurofilament heavy chain (NfH) and neurofilament light chain (NfL). RESULTS: Sixty-four patients had blood sampling. Of these, 58 and 56 were available at 3 months, and 55 and 54 were available at 6 months for NfH and NfL, respectively. There was no significant correlation between serum NfH and NfL at the time points tested. For NfH, the difference in mean placebo - phenytoin was -44 pg/ml at 3 months (P = 0.019) and -27 pg/ml at 6 months (P = 0.234). For NfL, the difference was 1.4 pg/ml at 3 months (P = 0.726) and -1.6 pg/ml at 6 months (P = 0.766). CONCLUSIONS: At 3 months, there was a reduction in NfH, but not NFL, in the phenytoin versus placebo group, while differences at 6 months were not statistically significant. This suggests a potential neuroprotective role for phenytoin in acute ON, with the lower NfH at 3 months, when levels secondary to degeneration of the anterior visual pathway are still elevated, but not at 6 months, when levels have normalized.


Assuntos
Neurite Óptica , Fenitoína , Biomarcadores , Humanos , Filamentos Intermediários , Proteínas de Neurofilamentos , Neuroproteção , Neurite Óptica/tratamento farmacológico , Fenitoína/uso terapêutico
5.
Eye (Lond) ; 35(5): 1418-1426, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32555545

RESUMO

BACKGROUND/AIMS: Optic nerve sheath fenestration (ONSF) is a surgical intervention in the management of idiopathic intracranial hypertension (IIH) infrequently performed in the United Kingdom. Numerous surgical approaches have been described, including medial transconjunctival, lateral and endoscopic. We describe our outcomes and complications from ONSF via a supero-medial eyelid skin crease incision in patients with IIH. METHODS: We performed a retrospective review of consecutive patients undergoing ONSF for IIH between January 2011 and December 2017 by a single surgeon. RESULTS: Thirty patients were included in the analysis with a median follow-up of 14.5 months. Bilateral ONSFs were undertaken in 27 (90%). The data from one eye per patient were analysed. The mean kinetic perimetry score in mean radial degrees of the I4e isopter improved from 27.3° to 35.7°, p = 0.04. After removing cases with optic atrophy, the median modified Frisén grade of papilloedema improved from 2.5 to 1.0, p = 0.007. A total of 5/30 (17%) patients had complications: two (7%) had recurrence/late failure (one managed medically and one with cerebrospinal fluid [CSF] diversion surgery), one had transient cotton wool spots post-operatively, one had transient retinal haemorrhages and one patient had a transiently oval pupil. No patients had repeat ONSF, but CSF diversion surgery was subsequently carried out in 4/30 (13%) patients. CONCLUSIONS: ONSF via a supero-medial eyelid skin crease approach is effective at improving visual function in patients with IIH. The complication rates are low when compared with CSF diversion surgery and other surgical approaches for ONSF.


Assuntos
Pseudotumor Cerebral , Descompressão Cirúrgica , Pálpebras/cirurgia , Humanos , Nervo Óptico/cirurgia , Pseudotumor Cerebral/cirurgia , Estudos Retrospectivos , Reino Unido
7.
Case Rep Infect Dis ; 2020: 4630809, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32733717

RESUMO

Streptococcus constellatus is an oropharyngeal commensal Gram-positive coccus, frequently associated with the respiratory tract. S. constellatus is part of the Streptococcus anginosus or milleri group, which has traditionally been considered to have propensity to cause empyema and purulent abscesses, a property that is sometimes overlooked as the severity of infections it causes may have a varying degree. In this case, we present the case of a 54-year-old male with known liver cirrhosis who developed a severe empyema during an acute liver failure episode, requiring extensive decortication and prolonged hospital admission.

8.
BMJ Open ; 9(8): e027529, 2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31434767

RESUMO

OBJECTIVE: Most skin lesions first present in primary care, where distinguishing rare melanomas from benign lesions can be challenging. Dermoscopy improves diagnostic accuracy among specialists and is promoted for use by primary care physicians (PCPs). However, when used by untrained clinicians, accuracy may be no better than visual inspection. This study aimed to undertake a systematic review of literature reporting use of dermoscopy to triage suspicious skin lesions in primary care settings, and challenges for implementation. DESIGN: A systematic literature review and narrative synthesis. DATA SOURCES: We searched MEDLINE, Cochrane Central, EMBASE, Cumulative Index to Nursing and Allied Health Literature, and SCOPUS bibliographic databases from 1 January 1990 to 31 December 2017, without language restrictions. INCLUSION CRITERIA: Studies including assessment of dermoscopy accuracy, acceptability to patients and PCPs, training requirements, and cost-effectiveness of dermoscopy modes in primary care, including trials, diagnostic accuracy and acceptability studies. RESULTS: 23 studies met the review criteria, representing 49 769 lesions and 3708 PCPs, all from high-income countries. There was a paucity of studies set truly in primary care and the outcomes measured were diverse. The heterogeneity therefore made meta-analysis unfeasible; the data were synthesised through narrative review. Dermoscopy, with appropriate training, was associated with improved diagnostic accuracy for melanoma and benign lesions, and reduced unnecessary excisions and referrals. Teledermoscopy-based referral systems improved triage accuracy. Only three studies examined cost-effectiveness; hence, there was insufficient evidence to draw conclusions. Costs, training and time requirements were considered important implementation barriers. Patient satisfaction was seldom assessed. Computer-aided dermoscopy and other technological advances have not yet been tested in primary care. CONCLUSIONS: Dermoscopy could help PCPs triage suspicious lesions for biopsy, urgent referral or reassurance. However, it will be important to establish further evidence on minimum training requirements to reach competence, as well as the cost-effectiveness and patient acceptability of implementing dermoscopy in primary care. TRIAL REGISTRATION NUMBER: CRD42018091395.


Assuntos
Dermoscopia/métodos , Melanoma/diagnóstico , Neoplasias Cutâneas/diagnóstico , Triagem/métodos , Biópsia , Humanos , Atenção Primária à Saúde , Reprodutibilidade dos Testes
9.
Clin Radiol ; 74(5): 357-366, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30898381

RESUMO

This article reviews current limitations and future opportunities for the application of computer-aided detection (CAD) systems and artificial intelligence in breast imaging. Traditional CAD systems in mammography screening have followed a rules-based approach, incorporating domain knowledge into hand-crafted features before using classical machine learning techniques as a classifier. The first commercial CAD system, ImageChecker M1000, relies on computer vision techniques for pattern recognition. Unfortunately, CAD systems have been shown to adversely affect some radiologists' performance and increase recall rates. The Digital Mammography DREAM Challenge was a multidisciplinary collaboration that provided 640,000 mammography images for teams to help decrease false-positive rates in breast cancer screening. Winning solutions leveraged deep learning's (DL) automatic hierarchical feature learning capabilities and used convolutional neural networks. Start-ups Therapixel and Kheiron Medical Technologies are using DL for breast cancer screening. With increasing use of digital breast tomosynthesis, specific artificial intelligence (AI)-CAD systems are emerging to include iCAD's PowerLook Tomo Detection and ScreenPoint Medical's Transpara. Other AI-CAD systems are focusing on breast diagnostic techniques such as ultrasound and magnetic resonance imaging (MRI). There is a gap in the market for contrast-enhanced spectral mammography AI-CAD tools. Clinical implementation of AI-CAD tools requires testing in scenarios mimicking real life to prove its usefulness in the clinical environment. This requires a large and representative dataset for testing and assessment of the reader's interaction with the tools. A cost-effectiveness assessment should be undertaken, with a large feasibility study carried out to ensure there are no unintended consequences. AI-CAD systems should incorporate explainable AI in accordance with the European Union General Data Protection Regulation (GDPR).


Assuntos
Inteligência Artificial/tendências , Neoplasias da Mama/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Mamografia/métodos , Mama/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador/tendências , Mamografia/tendências
10.
Neuroophthalmology ; 40(2): 59-68, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27928387

RESUMO

Sarcoidosis can affect the optic nerves by means of optic disc oedema secondary to posterior uveitis, optic disc oedema secondary to raised intracranial pressure, optic neuritis, optic atrophy secondary to compression or infiltration from a primary central nervous system lesion, and primary granuloma of the optic nerve head. The authors report the use of optical coherence tomography in assessing the response to immunosuppression in a 57-year-old woman with an optic nerve head granuloma.

12.
Clin Otolaryngol ; 40(6): 704-14, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26769686

RESUMO

BACKGROUND: Otogenic paediatric cerebral venous sinus thrombosis (CVST) is rare but has potential clinical sequelae. Its management has long been debated mainly concerning the role of surgery and the use of anticoagulant therapy. OBJECTIVE OF REVIEW: To review the current literature and examine the medical and surgical management of paediatric otogenic CVST and its clinical and radiological outcome. TYPE OF REVIEW: Systematic review. SEARCH STRATEGY: The electronic databases (MEDLINE, EMBASE, Cochrane) were searched from inception to November 2014 using text words 'cerebral venous sinus thrombosis OR cerebral venous thrombosis OR lateral sinus thrombosis OR sigmoid sinus thrombosis' AND 'otogenic OR mastoiditis OR otitis media' AND 'children OR paediatric OR pediatric'. EVALUATION METHOD: Inclusion criteria were applied by two reviewers and data extraction was carried out. The type of otological surgery (conservative versus extensive) and the use of anticoagulants with their clinical and radiological outcomes were tabulated. RESULTS: Thirty-six studies (15 case reports and 21 case series) were included with a total of 190 patients. A total of 92.1% of patients underwent otological surgery, and 69.5% had conservative surgery and 30.5% extensive otological surgery. Anticoagulants were used in 59%. A total of 79.2% of patients were reported to have had a good clinical outcome. Within this group, 56% had conservative surgery and anticoagulants. Follow-up scans were documented in 61.6% of patients and complete recanalisation was observed in 51%. Complete recanalisation was observed in 47% of those who had been anticoagulated and 55% of those who received no anticoagulation. CONCLUSIONS: Conservative otological surgery with the combination of anticoagulation was the most common treatment modality found in the group of patients with good clinical outcome. However, given the current low level of evidence, a multicentre collaborative study is needed to help establish the optimum surgical approach and the role of anticoagulation in managing paediatric otogenic CVST.


Assuntos
Anticoagulantes/uso terapêutico , Gerenciamento Clínico , Trombose do Seio Lateral/tratamento farmacológico , Otite Média/complicações , Humanos , Trombose do Seio Lateral/etiologia
13.
Neuroophthalmology ; 38(6): 310-319, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-27928318

RESUMO

A retrospective notes review was conducted for 50 consecutive patients who underwent shunt surgery for idiopathic intracranial hypertension (IIH). The decimal visual acuity and the mean radial degrees (MRD) of the I4e isopter of the Goldmann visual field were measured pre-operatively and after a mean follow-up period of 1123 days (range: 13-3551 days). A ventriculo-peritoneal shunt was the first procedure in 38 patients and a lumbo-peritoneal shunt in 12. The mean decimal visual acuity of the worse affected eye improved from 0.75 to 0.84, p = 0.011. The MRD score of the worse affected eye improved on average from 25.6° to 35.5°, p < 0.0001. In those with significant pre-operative visual impairment in their worse affected eye (defined as an MRD score ≤30°), the MRD score improved on average from 10.3° to 26.5°, p = 0.0008. The mean number of surgical procedures for each patient was 2.8 (range: 1-15). Taking all surgical procedures into account, post-operative complications were experienced by 30 patients. At last follow-up, 28 patients still complained of headache, 8 of whom had the intervention performed primarily for headache. Shunting can improve visual function in patients with IIH. There is significant post-operative morbidity and often the need for repeated procedures. Headache also commonly remains in these patients. There is a need for a randomised controlled trial of operative interventions in IIH. Sample size calculations for such a trial to treat significant vision loss are presented.

14.
Neuroophthalmology ; 37(4): 146-156, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-28167978

RESUMO

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) can lead to prominent nerve hypertrophy, which can mimic other forms of neuropathy radiologically. Neuro-ophthalmological complications can also occur in CIDP, either at presentation or chronically in the disorder. This can also cause diagnostic difficulties. We report three cases of neuro-ophthalmological complications of CIDP: two cases of papilloedema and one case of proptosis. In all three cases cranial nerve hypertrophy was present. CIDP should be considered in neuro-ophthalmological presentations associated with cranial/spinal nerve root hypertrophy.

15.
Eur J Neurol ; 18(10): 1266-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21426442

RESUMO

BACKGROUND AND PURPOSE: The purpose of this study was to identify the incidence and prevalence of idiopathic intracranial hypertension (IIH) in Sheffield, UK. METHODS: A retrospective review of case notes was conducted to identify cases of IIH seen between 1 January 2007 and 31 December 2008. RESULTS: Sixteen (15 women and 1 man) new patients were identified to give an incidence within Sheffield of 1.56/100,000/year and 2.86/100,000/year for women. The incidence of IIH in obese women was 11.9/100,000/year. The prevalence of IIH was calculated as 10.9/100,000, and 85.7/100,000 in obese women. CONCLUSION: A higher incidence of IIH than previously reported UK data was found, which may be because of increasing obesity within the population, or improved case ascertainment.


Assuntos
Obesidade/epidemiologia , Pseudotumor Cerebral/diagnóstico , Pseudotumor Cerebral/epidemiologia , Adulto , Comorbidade , Feminino , Humanos , Incidência , Masculino , Obesidade/diagnóstico , Prevalência , Estudos Retrospectivos , Reino Unido/epidemiologia , Adulto Jovem
19.
Neurology ; 65(10): 1526-32, 2005 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-16301477

RESUMO

Diffusion imaging is a quantitative, MR-based technique potentially useful for the study of multiple sclerosis (MS), due to its increased pathologic specificity over conventional MRI and its ability to assess in vivo the presence of tissue damage occurring outside T2-visible lesions, i.e., in the so-called normal-appearing white and gray matter. The present review aims at critically summarizing the state-of-the-art and providing a background for the planning of future diffusion studies of MS. Several pieces of evidence suggest that diffusion-weighted and diffusion tensor MRI are sensitive to MS damage and able to detect its evolution over relatively short periods of time. Although a significant relationship between diffusion-weighted MRI findings and MS clinical disability was not found in the earliest studies, with improved diffusion imaging technology correlations between diffusion abnormalities and MS clinical aspects are now emerging. However, the best acquisition and postprocessing strategies for MS studies remain a matter of debate and the contribution of newer and more sophisticated techniques to diffusion tensor MRI investigations in MS needs to be further evaluated. Although changes in diffusion MRI indices reflect a net loss of structural organization, at present we can only speculate on their possible pathologic substrates in the MS brain. Postmortem studies correlating diffusion findings with histopathology of patients with MS are, therefore, also warranted.


Assuntos
Sistema Nervoso Central/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Difusão por Ressonância Magnética/normas , Esclerose Múltipla/diagnóstico , Autopsia/normas , Sistema Nervoso Central/fisiopatologia , Difusão , Imagem de Difusão por Ressonância Magnética/tendências , Humanos , Esclerose Múltipla/fisiopatologia , Fibras Nervosas Mielinizadas/química , Fibras Nervosas Mielinizadas/metabolismo , Fibras Nervosas Mielinizadas/patologia , Mudanças Depois da Morte , Valor Preditivo dos Testes , Degeneração Walleriana/diagnóstico , Degeneração Walleriana/fisiopatologia
20.
Mult Scler ; 11(5): 537-41, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16193891

RESUMO

Although multiple sclerosis (MS) frequently involves the optic nerves, imaging this structure is not yet performed routinely in clinical practice. The recent improvement of magnetic resonance (MR) technology and the development of new MR strategies, capable of providing an, in vivo, overall assessment of MS pathology has allowed objective metrics to be obtained for monitoring disease evolution, essentially in the brain. However, despite this progress, the correlation between brain MR metrics of the disease and clinical disability are still disappointing. An objective and accurate estimate of the presence and extent of optic nerve involvement might help to overcome this clinical/MRI paradox. This review summarizes the main results obtained from the application of conventional and modern MR-based techniques for the evaluation of optic nerve damage in MS.


Assuntos
Imageamento por Ressonância Magnética , Esclerose Múltipla/patologia , Nervo Óptico/patologia , Neurite Óptica/patologia , Atrofia , Humanos
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