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1.
Clin Radiol ; 77(1): e64-e74, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34716007

RESUMO

AIM: To review outcomes of male patients attending the breast unit, evaluate effectiveness of imaging and examination in detecting breast cancer and review adherence to guidelines for male breast imaging. MATERIALS AND METHODS: A retrospective review was undertaken of male patients attending Cambridge Breast Unit from 1 January 2015 to 31 December 2019. Patient electronic records and imaging were reviewed to establish demographics, clinical findings, imaging, biopsy, and pathology outcomes. RESULTS: Of 1,362 male patients attending the breast unit, 1,028 (75%) had imaging performed. Biopsy was performed in 41 men (3%), with 14 cancers diagnosed (1%). Clinical examination showed 42.7% sensitivity, 99.6% specificity, 54.6% positive predictive value (PPV) and 99.4% negative predictive value (NPV) for detection of cancer. Mammogram demonstrated 84.6% sensitivity, 99.4% specificity, 69.8% PPV, and 99.8% NPV for detection of malignancy. Ultrasound demonstrated 78.6% sensitivity, 98.9% specificity, 73.3% PPV and 99.2% NPV for detection of cancer. Forty-one percent of patients <40 years and 51% < 50 years were imaged, who according to local and Royal College of Radiologists (RCR) guidelines did not require imaging based on age and clinical score. CONCLUSION: Male patients account for a small proportion of referrals to the breast unit but generate significant workload. Imaging protocols, incorporating clinical score and age cut-off at 40 years remains robust for detecting malignancy. Clinician awareness of the imaging protocol, and close liaison with radiologists is essential to minimise additional radiology workload.


Assuntos
Neoplasias da Mama Masculina/diagnóstico por imagem , Fidelidade a Diretrizes/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Mama/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
2.
Clin Radiol ; 75(10): 757-762, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32646605

RESUMO

AIM: To determine imaging and pathological outcomes in cases of unprovoked venous thromboembolism (VTE) referred for mammogram. A secondary objective was to elucidate outcomes of abdominopelvic computed tomography (CT) imaging performed in this cohort. MATERIALS AND METHODS: A retrospective review of mammograms performed in cases of unprovoked VTE was undertaken from January 2016 to September 2019. Patient notes and imaging were reviewed to establish patient demographics, additional imaging required, biopsies performed, pathology findings, and eventual outcomes. Cases were reviewed to determine if concurrent CT abdomen/pelvis was performed to screen for malignancy. Outcomes of CT were recorded. RESULTS: One hundred and thirty-nine women attended for screening mammogram following unprovoked VTE during the study period. Mean patient age was 68 years (range 42-89 years). Fourteen women (10%) were recalled for further breast imaging, with two cases of confirmed malignancy (1.4%). Of the 139 women, 118 also underwent CT imaging, with 18 patients (15%) recalled for further investigations. Two (1.7%) cases of malignancy (lung and ovarian) were identified. CONCLUSION: A low cancer detection rate was demonstrated in women undergoing mammography or CT following unprovoked VTE. In addition, the high number of false-positive findings and need for additional investigations questions the value of screening in this setting. Based on these findings, Cambridge Breast Unit has ceased mammographic and abdominopelvic CT imaging in women with unprovoked VTE, anticipating the newly updated National Institute for Health and Care Excellence (NICE) guidelines.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Mamografia , Programas de Rastreamento/métodos , Tomografia Computadorizada por Raios X , Tromboembolia Venosa/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Detecção Precoce de Câncer , Inglaterra , Feminino , Humanos , Pessoa de Meia-Idade , Radiografia Abdominal , Fatores de Risco
3.
Clin Radiol ; 72(6): 517.e7-517.e12, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28069161

RESUMO

AIM: To determine the breast cancer detection rate at routine bilateral screening mammography in women aged 35-39 years attending a symptomatic breast clinic, in women of population-risk profile with a normal clinical examination. METHODS AND MATERIALS: A retrospective analysis of all mammograms performed on patients aged 35-39 years at St James's Hospital from 2011-2015 was carried out. Patients with moderate or high familial risk of breast cancer, personal breast cancer history or chest radiation, males, general practitioner (GP) and internal hospital referrals, and those with abnormal clinical examinations were excluded. Included women had "normal", "benign", or undocumented examination findings. Results of imaging, including ultrasound and histopathological results, were recorded. Information was extracted from the hospital's electronic record systems. RESULTS: Of 4,087 patients aged 35-39 who had bilateral mammograms from 2011-2015, 2,148 patients were excluded from analysis. Of 1,939 included women, four (0.21%) were diagnosed with breast cancer confirmed at histology based on mammographic findings: two invasive ductal carcinoma (8 and 2 mm) and two ductal carcinoma in situ (DCIS; 4.5 mm high-grade DCIS and 2 mm low-grade DCIS). Other histological findings included two B3, 46 B2, and three B1 lesions. Overall, 115 biopsies were performed in this cohort; 55 (47.8%) were attributable to mammographic screening, producing a biopsy rate of 2.8% due to mammography alone. CONCLUSION: Per 1,000 women screened, 2.1 cases of cancer were detected. This figure would be below accepted international thresholds to undertake screening mammography and raises radiation protection issues. Additionally, a large number of benign biopsies were undertaken, with likely resultant psychological impact. Further studies could inform national guidance.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Detecção Precoce de Câncer , Mamografia , Adulto , Feminino , Humanos , Estudos Retrospectivos
4.
Opt Lett ; 41(8): 1700-3, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-27082323

RESUMO

Since their first demonstration some 25 years ago, thermally poled silica fibers have been used to realize device functions such as electro-optic modulation, switching, polarization-entangled photons, and optical frequency conversion with a number of advantages over bulk free-space components. We have recently developed an innovative induction poling technique that could allow for the development of complex microstructured fiber geometries for highly efficient χ(2)-based device applications. To systematically implement these more advanced poled fiber designs, we report here the development of comprehensive numerical models of the induction poling mechanism itself via two-dimensional (2D) simulations of ion migration and space-charge region formation using finite element analysis.

5.
Clin Radiol ; 71(11): 1143-7, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27542654

RESUMO

AIM: To review all surveillance breast magnetic resonance imaging (MRI) examinations performed over a 6-year period at an Irish national centre to determine the recall rate, biopsy rate, and cancer-detection rates. MATERIALS AND METHODS: All breast MRI examinations performed for surveillance purposes in women at high risk of developing breast cancer between January 2009 and December 2014 were reviewed. The Breast Imaging-Reporting and Data System (BI-RADS) score for each MRI examination was determined, the type of additional imaging performed, and the method of biopsy, if performed, was recorded. Histology of the biopsy specimens was reviewed. RESULTS: Data for 715 women undergoing 1445 surveillance MRI examinations were identified. Of the examinations, 10.9% (157/1445) had MRI BI-RADS scores that required recall for further imaging and 6.3% (91/1445) required a biopsy. Recall rates were 14.2% (86/607) and 8.5% (71/838) in the prevalent and incident rounds, respectively. The overall cancer detection rate was 17 per 1000. CONCLUSION: The current UK guideline was not achieved and no studies to date have achieved the target of <7%. Aiming for this target could risk lowering the cancer-detection rate. The authors would suggest a target rate of <15% and <10% for the prevalent round and incident rounds, respectively.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/epidemiologia , Detecção Precoce de Câncer/estatística & dados numéricos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Mamografia/estatística & dados numéricos , Biópsia/estatística & dados numéricos , Mama/diagnóstico por imagem , Mama/patologia , Neoplasias da Mama/patologia , Feminino , Humanos , Incidência , Irlanda/epidemiologia , Mamografia/métodos , Prevalência , Estudos Retrospectivos , Risco
7.
Opt Express ; 23(13): 17263-8, 2015 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-26191735

RESUMO

A hybrid silicon-core, silica-clad microspherical resonator has been fabricated from the semiconductor core fiber platform. Linear and nonlinear characterization of the resonator properties have shown it to exhibit advantageous properties associated with both materials, with the low loss cladding supporting high quality (Q) factor whispering gallery modes which can be tuned through the nonlinear response of the crystalline core. By exploiting the large wavelength shift associated with the Kerr nonlinearity, we have demonstrated all-optical modulation of a weak probe on the timescale of the femtosecond pump pulse. This novel geometry offers a route to ultra-low loss, high-Q silica-based resonators with enhanced functionality.

8.
Ir Med J ; 108(10): 310-1, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26817290

RESUMO

Fat embolism syndrome usually occurs following trauma where fat globules from long bone fractures produce pulmonary, cerebral or cutaneous effects. This case illustrates the presence of macroscopic fat in the right common femoral vein secondary to a long bone fracture. This finding is rare but should be looked for on cross-sectional imaging to allow early, aggressive treatment of fat embolism syndrome.


Assuntos
Embolia Gordurosa/etiologia , Ferimentos e Lesões/complicações , Acidentes de Trânsito , Embolia Gordurosa/diagnóstico por imagem , Veia Femoral/diagnóstico por imagem , Humanos , Masculino , Tomografia Computadorizada por Raios X , Adulto Jovem
9.
Opt Lett ; 39(22): 6513-6, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25490507

RESUMO

Conventional thermal poling methods require direct physical contact to internal fiber electrodes. Here, we report an indirect electrostatic induction technique using electrically floating wires inside the fiber combined with external electric fields that can allow for facile poling of complex microstructured fibers (MOFs) of arbitrarily long lengths. In combination with our unique ability to use liquid gallium electrodes, inducing second-order nonlinearities inside otherwise difficult to access multi-core or multi-hole MOFs now becomes entirely feasible and practical. The formation of a permanent second-order nonlinearity is unequivocally demonstrated by realizing quasi-phase-matched frequency doublers using periodic UV erasure methods in the induction-poled fibers. The second-order susceptibility created inside the fiber is driven by the potential difference established between the floating electrodes, which we calculate via numerical simulations.

10.
Opt Lett ; 39(19): 5721-4, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25360968

RESUMO

An octave-spanning supercontinuum is generated in a hydrogenated amorphous silicon core fiber when pumped in the mid-infrared regime. The broadband wavelength conversion which extends from the edge of the telecommunications band into the mid-infrared (1.64-3.37 µm) is generated by four-wave mixing (FWM) and subsequent pulse break-up, facilitated by the high material nonlinear figure of merit and the anomalous dispersion of the relatively small 1.7 µm diameter core fiber. The FWM sidebands and corresponding supercontinuum can be tuned through the pump parameters, and show good agreement with the predicted phase-matching curves for the fiber.

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