Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 40
Filtrar
1.
Br J Surg ; 106(4): 367-374, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30706453

RESUMEN

BACKGROUND: The effect of sarcopenia based on the total psoas muscle area (TPMA) on CT is inconclusive in patients undergoing abdominal aortic aneurysm (AAA) intervention. The aim of this prospective cohort study was to evaluate morphometric sarcopenia as a method of risk stratification in patients undergoing elective AAA intervention. METHODS: TPMA was measured on preintervention CT images of patients undergoing elective endovascular aneurysm repair (EVAR) or open aneurysm repair. Mortality was assessed in relation to preintervention TPMA using Cox regression analysis, with calculation of hazard ratios at 30 days, 1 year and 4 years. Postintervention morbidity was evaluated in terms of postintervention care, duration of hospital stay and 30-day readmission. Changes in TPMA on surveillance EVAR imaging were also evaluated. RESULTS: In total, 382 patient images acquired between March 2008 and December 2016 were analysed. There were no significant intraobserver and interobserver differences in measurements of TPMA. Preintervention TPMA failed to predict morbidity and mortality at all time points. The mean(s.d.) interval between preintervention and surveillance imaging was 361·3(111·2) days. A significant reduction in TPMA was observed in men on surveillance imaging after EVAR (mean reduction 0·63(1·43) cm2 per m2 ; P < 0·001). However, this was not associated with mortality (adjusted hazard ratio 1·00, 95 per cent c.i. 0·99 to 1·01; P = 0·935). CONCLUSION: TPMA is not a suitable risk stratification tool for patients undergoing effective intervention for AAA.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Angiografía por Tomografía Computarizada/métodos , Procedimientos Quirúrgicos Electivos/métodos , Procedimientos Endovasculares/métodos , Músculos Psoas/diagnóstico por imagen , Sarcopenia/diagnóstico por imagen , Anciano , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/mortalidad , Estudios de Cohortes , Procedimientos Quirúrgicos Electivos/mortalidad , Procedimientos Endovasculares/mortalidad , Femenino , Mortalidad Hospitalaria/tendencias , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Análisis de Regresión , Análisis de Supervivencia , Resultado del Tratamiento
2.
Clin Radiol ; 74(6): 429-434, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30846190

RESUMEN

AIM: To provide an update of current practice in iliac artery intervention in the UK. MATERIALS AND METHODS: Ninety-nine interventional units across the UK completed online submission forms for iliac angioplasty and stent procedures between 2011 and 2014 (inclusive) for the British Iliac Angioplasty and Stenting (BIAS) IV registry. RESULTS: Data for 8,294 procedures were submitted during the study period. A total of 12,253 iliac segments were treated in 10,311 legs. The commonest indication was claudication (n=5219, 64.4%). Of the cases performed, 6,582 (80.8%) were performed electively with 3,548 (44.8%) of the procedures performed as a day-case and 6,586 (54%) of the lesions were treated with stents. Successful endovascular intervention (residual stenosis ≤49%) was achieved in 11,847 (97%) of treated segments, with residual stenosis in 1.5%. One point five percent of lesions could not be crossed with a wire. Limb complications were recorded in 366 (3.5%), resulting in 141 patients undergoing an unplanned intervention and 173 (2.2%) patients had a systemic complication. There were 84 deaths prior to discharge, of which 13 (15%) were procedure related. Both systemic and limb complication rates were higher in patients undergoing treatment for critical ischaemia. CONCLUSION: Iliac stenting and angioplasty are associated with high technical success with a low complication rate. These data provide up-to-date statistics for patient information and future audit and benchmarking purposes.


Asunto(s)
Angioplastia/métodos , Arteriopatías Oclusivas/diagnóstico por imagen , Arteriopatías Oclusivas/terapia , Arteria Ilíaca/diagnóstico por imagen , Radiología Intervencionista/métodos , Sistema de Registros , Stents , Humanos , Resultado del Tratamiento , Reino Unido
3.
Clin Radiol ; 73(9): 800-809, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29921442

RESUMEN

AIM: To ascertain current percutaneous lung biopsy practices around the UK. MATERIALS AND METHODS: A web-based survey was sent to all British Society of Thoracic Imaging (BSTI) and British Society of Interventional Radiology (BSIR) members (May 2017) assessing all aspects of lung biopsy practice. Responses were collected anonymously. RESULTS: Two hundred and thirty-nine completed responses were received (28.8% response rate). Of the respondents, 48.5% worked in a teaching hospital and 51.5% in a district general hospital, while 32.6% (78/239) were specialist thoracic radiologists, 29.2% (70/239) "general" radiologists with a thoracic subspecialty interest, and 28% (67/239) interventional radiologists. Of the respondents, 30.1% (72/239) did not require pre-biopsy lung function tests (PFTs); 45.6% (108/237) stopped aspirin before the procedure; 97.5% primarily use computed tomography (CT) guidance for biopsy and 88.7% (212/239) perform core needle biopsy (CNB); and 86.6% of radiologists use a co-axial technique. There was wide variation in the number of samples routinely taken with most radiologists performing 1-2 passes (55.9%) or 3-4 passes (40.8%). Sixty-four percent reported using chest drain prevention techniques to minimise the impact of iatrogenic pneumothorax, with needle aspiration most frequent (43.9%). Timing of post-biopsy chest radiography (CXR), performed by 95.8% (228/239), also varied greatly: most commonly at either 1 hour (23%), 2 hours (24.7%), or 4 hours (22.6%). Moreover, the time of patient discharge after uncomplicated biopsy was variable, although the majority (66.1%) discharge patients after ≥4 hours. CONCLUSION: There are striking variations among surveyed UK radiologists performing lung biopsy in decision-making, pre-biopsy work-up, post-biopsy monitoring, management of pneumothorax, and discharge. The results suggest a need for new updated national percutaneous lung biopsy guidelines.


Asunto(s)
Biopsia con Aguja/métodos , Biopsia Guiada por Imagen/métodos , Neoplasias Pulmonares/patología , Pautas de la Práctica en Medicina/estadística & datos numéricos , Radiografía Intervencional/métodos , Biopsia con Aguja/efectos adversos , Toma de Decisiones , Detección Precoz del Cáncer , Femenino , Humanos , Biopsia Guiada por Imagen/efectos adversos , Masculino , Persona de Mediana Edad , Radiografía Torácica/métodos , Encuestas y Cuestionarios , Reino Unido
4.
Mol Psychiatry ; 17(11): 1116-29, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21876539

RESUMEN

Coffee consumption is a model for addictive behavior. We performed a meta-analysis of genome-wide association studies (GWASs) on coffee intake from 8 Caucasian cohorts (N=18 176) and sought replication of our top findings in a further 7929 individuals. We also performed a gene expression analysis treating different cell lines with caffeine. Genome-wide significant association was observed for two single-nucleotide polymorphisms (SNPs) in the 15q24 region. The two SNPs rs2470893 and rs2472297 (P-values=1.6 × 10(-11) and 2.7 × 10(-11)), which were also in strong linkage disequilibrium (r(2)=0.7) with each other, lie in the 23-kb long commonly shared 5' flanking region between CYP1A1 and CYP1A2 genes. CYP1A1 was found to be downregulated in lymphoblastoid cell lines treated with caffeine. CYP1A1 is known to metabolize polycyclic aromatic hydrocarbons, which are important constituents of coffee, whereas CYP1A2 is involved in the primary metabolism of caffeine. Significant evidence of association was also detected at rs382140 (P-value=3.9 × 10(-09)) near NRCAM-a gene implicated in vulnerability to addiction, and at another independent hit rs6495122 (P-value=7.1 × 10(-09))-an SNP associated with blood pressure-in the 15q24 region near the gene ULK3, in the meta-analysis of discovery and replication cohorts. Our results from GWASs and expression analysis also strongly implicate CAB39L in coffee drinking. Pathway analysis of differentially expressed genes revealed significantly enriched ubiquitin proteasome (P-value=2.2 × 10(-05)) and Parkinson's disease pathways (P-value=3.6 × 10(-05)).


Asunto(s)
Moléculas de Adhesión Celular/genética , Café/genética , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A2/genética , Ingestión de Líquidos/genética , Estudio de Asociación del Genoma Completo/métodos , Antígenos de Neoplasias/genética , Proteínas Reguladoras de la Apoptosis/genética , Cafeína/farmacología , Línea Celular , Femenino , Expresión Génica/efectos de los fármacos , Perfilación de la Expresión Génica/métodos , Predisposición Genética a la Enfermedad/genética , Humanos , Masculino , Enfermedad de Parkinson/genética , Polimorfismo de Nucleótido Simple , Proteínas Serina-Treonina Quinasas/genética , Población Blanca/genética
5.
Eur J Vasc Endovasc Surg ; 42(5): 608-14, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21852165

RESUMEN

OBJECTIVES: The United Kingdom abdominal aortic aneurysm (AAA) screening programme refers aneurysms with ultrasound (US) diameters of ≥5.5 cm to vascular services for consideration of computed tomography (CT) and intervention. We investigated the discrepancy between US and CT, implications on clinical decisions and question at which stage CT be used. DESIGN/METHODS: AAA USs over 5 years were retrospectively analysed. Patients included had aneurysms measuring ≥5 cm on US with subsequent CT within 2 months (n = 123). Based on maximum US diameters, 44 patients had aneurysms between 5 and 5.4 cm (group I) and 79 patients ≥5.5 cm (group II). Results were cross-referenced. Correlation and limits of agreement were calculated. Two radiologists re-measured 44 pairs of CT/US scans and the inter-observer bias in determining discrepancies between imaging modalities calculated. RESULTS: Mean difference between imaging modalities was 0.21 cm (±0.39 cm, p < 0.001). Limits of agreement were -0.55 to 0.96 cm, exceeding clinical acceptability. Mean difference was higher and significant in group I (0.39 cm, p < 0.001) compared to group II (0.10 cm, p > 0.05). Seventy-percent of group I patients had CT scans revealing diameters of ≥5.5 cm. Inter-observer bias was not significant. CONCLUSION: Significant differences between imaging modalities, more in US diameters of below 5.5 cm, exist. We recommend AAAs measuring ≥5 cm on US should undergo earlier referral to a vascular service and CT.


Asunto(s)
Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Anciano , Aneurisma de la Aorta Abdominal/terapia , Aortografía , Femenino , Humanos , Masculino , Variaciones Dependientes del Observador , Selección de Paciente , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Ultrasonografía
6.
Ann R Coll Surg Engl ; 102(5): 383-390, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32233869

RESUMEN

INTRODUCTION: Cardiopulmonary exercise testing (CPET) and transthoracic echocardiography (TTE) are common preparative investigations prior to elective endovascular aneurysm repair (EVAR). Whether these investigations can predict survival following EVAR and contribute to shared decision making is unknown. METHODS: Patients who underwent EVAR at a tertiary centre between June 2007 and December 2014 were identified from the National Vascular Registry. Variables obtained from preoperative investigations were assessed for their association with survival at three years. Regression analysis was used to determine variables that independently predicted survival at three years. RESULTS: A total of 199 patients underwent EVAR during the study period. Of these, 120 had preoperative CPET and 123 had TTE. Lower forced expiratory ventilation (FEV1), ratio of FEV1 to forced vital capacity, work at peak oxygen consumption and higher ventilatory equivalent for carbon dioxide were associated with increased mortality. Variables obtained from TTE were not associated with survival at three years although there was a low incidence of left ventricular systolic dysfunction and significant valvular disease in this cohort. CONCLUSIONS: CPET might be a useful adjunct to assist in shared decision making in patients undergoing elective EVAR and may influence anaesthetic technique. TTE does not appear to be able to discriminate between high and low risk individuals. However, a low rate of significant ventricular dysfunction and valvular disease in patients undergoing elective EVAR may account for these findings.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Prueba de Esfuerzo , Complicaciones Posoperatorias/prevención & control , Cuidados Preoperatorios/métodos , Anciano , Anciano de 80 o más Años , Aneurisma de la Aorta Abdominal/mortalidad , Ecocardiografía , Procedimientos Quirúrgicos Electivos/efectos adversos , Procedimientos Endovasculares/efectos adversos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Guías de Práctica Clínica como Asunto , Valor Predictivo de las Pruebas , Cuidados Preoperatorios/normas , Sistema de Registros/estadística & datos numéricos , Medición de Riesgo/métodos , Medición de Riesgo/normas , Factores de Riesgo , Análisis de Supervivencia , Factores de Tiempo , Resultado del Tratamiento
7.
Clin Radiol ; 64(5): 502-10, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19348846

RESUMEN

AIM: To audit the use of inferior vena cava (IVC) filter insertions at three UK centres over 12 years to assess whether trends in filter use in the UK mirrored those seen elsewhere. MATERIALS AND METHODS: Radiology department databases were interrogated for IVC filter insertions and removals between 1994 and 2006. Reports for these interventions, along with prior and subsequent imaging reports, were analysed. Follow-up data were obtained when available. RESULTS: Five hundred and sixteen filters were placed with a significant year-on-year trend towards increasing use. Fifty-seven percent of filters placed were for absolute indications and 37% for relative indications. The filters were used for prophylaxis in 6% of patients in the absence of proven pulmonary embolism (PE) or deep vein thrombosis (DVT). A retrievable filter was used in 74% of cases with retrieval attempted in 40% of these and no evidence of an increasing rate of retrieval over time. A significant complication related to insertion or retrieval was encountered in 0.4 and 1% of procedures, respectively. Mean 24 h and 30 day mortalities were 1 and 8%, respectively. There was an absence of organized follow-up at all three centres. CONCLUSION: IVC filter use in the UK is increasing. The use of retrievable filters has not resulted in increased filter retrieval. Filter insertion and retrieval is associated with a low risk of significant complication, but lack of systematic follow-up limits conclusions regarding safety and efficacy.


Asunto(s)
Remoción de Dispositivos/estadística & datos numéricos , Filtros de Vena Cava/estadística & datos numéricos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Toma de Decisiones , Remoción de Dispositivos/mortalidad , Remoción de Dispositivos/tendencias , Femenino , Humanos , Masculino , Auditoría Médica , Persona de Mediana Edad , Implantación de Prótesis/efectos adversos , Implantación de Prótesis/mortalidad , Implantación de Prótesis/tendencias , Embolia Pulmonar/diagnóstico por imagen , Embolia Pulmonar/prevención & control , Radiografía , Resultado del Tratamiento , Reino Unido , Filtros de Vena Cava/efectos adversos , Vena Cava Inferior/diagnóstico por imagen , Vena Cava Inferior/cirugía , Trombosis de la Vena/diagnóstico por imagen , Trombosis de la Vena/prevención & control , Adulto Joven
8.
Eur J Vasc Endovasc Surg ; 35(4): 405-12, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18262445

RESUMEN

OBJECTIVES: Modern conventional ultrasound is sensitive to slow flow, but may misclassify some tight stenoses as occlusion. Symptomatic patients with tight proximal internal carotid artery stenoses may benefit from carotid endarterectomy but those with occlusion or long-segment disease do not. DESIGN: A prospective study of the diagnostic accuracy of contrast-enhanced ultrasound (CE-US), 2D time-of-flight magnetic resonance angiography (2D-TOF MRA) and contrast-enhanced magnetic resonance angiography (CE-MRA) against a reference standard of digital subtraction angiography (DSA) in patients with apparent carotid occlusion on conventional ultrasound. MATERIALS AND METHODS: Thirty-one patients with apparent carotid occlusion on conventional ultrasound and with recent ispilateral hemispheric transient ischaemeic attacks (TIAs) were studied. The primary endpoint was confirmation of occlusion with a secondary endpoint of identification of a surgically correctible lesion. RESULTS: The sensitivity and specificity of CE-US, 2D-TOF MRA and CE-MRA for patency were 1 & 1, 0.33 & 1 and 0.6 & 1 respectively and for the detection of a surgically correctible lesion were 1 & 0.96, 0.67 & 1 and 1 and 0.96 respectively. CE-US was difficult to interpret, precluding confident diagnosis in 5 cases. CONCLUSIONS: 2D-TOF MRA had poor sensitivity for patency and cannot be recommended as a second-line investigation to assess vessels apparently occluded on conventional ultrasound. Confident diagnosis on CE-US and CE-MRA accurately identified occlusion. If occlusion is confirmed by either of these modalities, no further imaging is required. The relative advantages of CE-US or CE-MRA in this situation are uncertain.


Asunto(s)
Arteria Carótida Interna , Estenosis Carotídea/diagnóstico , Angiografía por Resonancia Magnética , Ultrasonografía Doppler en Color , Estenosis Carotídea/fisiopatología , Estenosis Carotídea/terapia , Medios de Contraste , Endarterectomía Carotidea , Humanos , Selección de Paciente , Estudios Prospectivos , Sensibilidad y Especificidad , Grado de Desobstrucción Vascular/fisiología
9.
Med Hypotheses ; 69(1): 113-6, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17196758

RESUMEN

Major theories about the etiologies of chronic mental illnesses such as bipolar disorder and schizophrenia include genetic and environmental factors such as famine and infection. It is likely that multiple genes play a role in the pathogenesis of these disorders, but no single gene has been identified as causative. Several viruses have been investigated as potential candidates, but conflicting reports exist. Although a relationship between bipolar disorder and schizophrenia with autoimmune disorders has also been documented for many years, reports are often conflicting. We hypothesize that parvovirus B19 (B19), a common human pathogen, due to its ability to infect the brain and induce autoimmunity, is a strong candidate that may unite prevailing theories. In particular, our preliminary data suggest that B19 may be most likely involved in co-morbid bipolar and autoimmune thyroid disorders in females. In schizophrenics, the gender trend may be reversed. We propose that there is a complex interaction between immuno-genetics, autoimmunity, gender, and B19 infection that leads to at least some forms of bipolar disorder and schizophrenia. Future studies that investigate this hypothesis are warranted and outlined.


Asunto(s)
Encefalitis Viral/virología , Trastornos Mentales/virología , Infecciones por Parvoviridae/virología , Parvovirus B19 Humano , Tiroiditis Autoinmune/virología , Adulto , Encéfalo/virología , Encefalitis Viral/complicaciones , Femenino , Humanos , Masculino , Trastornos Mentales/complicaciones , Persona de Mediana Edad , Modelos Biológicos , Infecciones por Parvoviridae/complicaciones , Factores Sexuales , Tiroiditis Autoinmune/complicaciones
10.
Br J Ophthalmol ; 89(11): 1427-32, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16234446

RESUMEN

AIMS: To evaluate the test-retest variability of stereometric parameter measurements made with the Heidelberg retina tomograph (HRT) and Heidelberg retina tomograph-II (HRT-II), and to establish which parameter(s) provided the most repeatable and reliable measurements with both devices. An investigation into the factors affecting the repeatability of the measurements of this parameter(s) was conducted. METHODS: 43 ocular hypertensive and 31 glaucoma subjects were recruited to a test-retest study. One eye from each subject underwent HRT and HRT-II imaging by two observers on each of two occasions within 6 weeks of each other. Lens grading was carried out by LOCS III grading and Scheimpflug camera generated densitogram analysis. RESULTS: Rim area (RA) and mean cup depth measurements were found to be least variable. Both inter-test reference height difference and image quality had a strong relation (R(2)>0.5, p<0.0001) with inter-test RA difference and, together, are responsible for 70% of RA measurement variability. Image quality was influenced by lens opacity, cylindrical error, and age. Inter-test RA measurement differences were unrelated to the observer or visit interval. CONCLUSIONS: RA represents an appropriate measure for monitoring glaucomatous progression. Reference height difference and image quality were the factors that most influenced RA measurement variability. Image analysis strategies that address these factors may reduce test-retest variability.


Asunto(s)
Glaucoma de Ángulo Abierto/diagnóstico , Tomografía/métodos , Adulto , Anciano , Anciano de 80 o más Años , Técnicas de Diagnóstico Oftalmológico , Femenino , Glaucoma de Ángulo Abierto/patología , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Disco Óptico/patología , Reproducibilidad de los Resultados
11.
Eye (Lond) ; 29(10): 1270-84, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26337943

RESUMEN

Glaucoma is a neurodegenerative disorder with established relationships with ocular structures such as the retinal nerve fibre layer (RNFL) and the ganglion cell layer (GCL). Ocular imaging techniques such as optical coherence tomography (OCT) allow for quantitative measurement of these structures. OCT has been used in the monitoring of glaucoma, as well as investigating other neurodegenerative conditions such as Alzheimer's disease (AD) and multiple sclerosis (MS). In this review, we highlight the association between these disorders and ocular structures (RNFL and GCL), examining their usefulness as biomarkers of neurodegeneration. The average RNFL thickness loss in patients with AD is 11 µm, and 7 µm in MS patients. Most of the studies investigating these changes are cross-sectional. Further longitudinal studies are required to assess sensitivity and specificity of these potential ocular biomarkers to neurodegenerative disease progression.


Asunto(s)
Enfermedad de Alzheimer/fisiopatología , Glaucoma/fisiopatología , Esclerosis Múltiple/fisiopatología , Fibras Nerviosas/patología , Enfermedades Neurodegenerativas/fisiopatología , Células Ganglionares de la Retina/patología , Enfermedad de Alzheimer/diagnóstico , Biomarcadores , Glaucoma/diagnóstico , Humanos , Esclerosis Múltiple/diagnóstico , Enfermedades Neurodegenerativas/diagnóstico
12.
Invest Ophthalmol Vis Sci ; 42(6): 1232-6, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11328732

RESUMEN

PURPOSE: A classical twin study was performed to examine the relative importance of genes and environment in refractive error. METHODS: Refractive error was examined in 226 monozygotic (MZ) and 280 dizygotic (DZ) twin pairs aged 49 to 79 years (mean age, 62.4 years). Using a Humphrey-670 automatic refractor, continuous measures of spherical equivalent, total astigmatism, and corneal astigmatism were recorded. Univariate and bivariate maximum likelihood model fitting was used to estimate genetic and environmental variance components using information from both eyes. RESULTS: For the continuous spectrum of myopia/hyperopia, a model specifying additive genetic and unique environmental factors showed the best fit to the data, yielding a heritability of 84% to 86% (95% confidence interval [CI], 81%-89%). If myopia and hyperopia (< or = -0.5 D and > or = 0.5 D, respectively) were treated as binary traits, the heritability was 90% (95% CI, 81%-95%) for myopia and 89% (95% CI, 81%-94%) for hyperopia. For total and corneal astigmatism, modeling showed dominant genetic effects are important; dominant genetic effects accounted for 47% to 49% of the variance of total astigmatism (95% CI, 37%-55%) and 42% to 61% of corneal astigmatism variance (95% CI, 8%-71%), with additive genetic factors accounting for 1% to 4% and 4% to 18%, respectively (95% CIs, 0%-13% and 0%-60%, respectively). CONCLUSIONS: Genetic effects are of major importance in myopia/hyperopia; astigmatism appears to be dominantly inherited.


Asunto(s)
Astigmatismo/genética , Enfermedades en Gemelos , Hiperopía/genética , Miopía/genética , Anciano , Femenino , Humanos , Persona de Mediana Edad , Gemelos Dicigóticos , Gemelos Monocigóticos
13.
Invest Ophthalmol Vis Sci ; 42(3): 601-5, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11222516

RESUMEN

PURPOSE: A classical twin study was performed to establish the relative importance of genes and environment in cortical cataract. METHODS: Five hundred six pairs of unselected female twin volunteers (226 monozygotic and 280 dizygotic) with a mean age of 62 years (range, 49-79 years) were examined. Cortical cataract was assessed using the slit-lamp-based Oxford Clinical Cataract Classification and Grading System (clinical grading) and the Wilmer Automated Grading System, which analyzed digital retroillumination images of subjects' lenses (digital grading). The worse eye categorized score for each individual was used in maximum likelihood path modeling of the correlations within twin pairs. These correlations were used to determine the underlying liability to cortical cataract. RESULTS: Prevalence of significant cortical cataract (>/=5% of lens area) was similar in monozygotic and dizygotic twins, occurring in 19.4% and 20.6% with the clinical grading system and 24% and 23% using the digital grading system, respectively. Modeling suggested liability to cortical cataract is explained by additive and dominant genes, individual environment, and age. Estimates of the broad sense heritability of cortical cataract were 58% (95% confidence interval [CI], 51%-64%) for the clinical grading system and 53% (95% CI, 45%-60%) for the digital system. Dominant genes were estimated to contribute to 38% (95% CI, 1%-64%) of the genetic effect with the clinical grading and 53% (95% CI, 28%-60%) with the digital grading. Individual environment explained 26% and 37% and age 16% and 11% of cortical cataract variance in clinical and digital gradings, respectively. CONCLUSIONS: Genetic effects are important in the development of cortical cataract and involve the action of dominant genes.


Asunto(s)
Envejecimiento/genética , Catarata/genética , Corteza del Cristalino/patología , Gemelos Dicigóticos/genética , Gemelos Monocigóticos/genética , Anciano , Catarata/clasificación , Catarata/diagnóstico , Femenino , Genes Dominantes , Humanos , Persona de Mediana Edad , Modelos Genéticos , Prevalencia
14.
Br J Ophthalmol ; 84(10): 1173-6, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11004106

RESUMEN

BACKGROUND/AIMS: Well dilated pupils make eye surgery easier. A classic twin study was established to examine the relative importance of genes and environment in the variance of pupil size after mydriasis, and to examine the effects of other factors such as age, iris colour, and refractive error. METHODS: 506 twin pairs, 226 monozygotic (MZ) and 280 dizygotic (DZ), aged 49-79 (mean age 62.2 years, SD 5.7) were examined. Dilated pupil size was measured using a standardised grid superimposed over digital retroillumination images taken 50-70 minutes after mydriasis using tropicamide 1% and phenylephrine 10%. Univariate maximum likelihood model fitting was used to estimate genetic and environmental variance components. RESULTS: Dilated pupil size was more highly correlated in MZ compared with DZ twins (intraclass correlation coefficients 0.82 and 0.39 respectively). A model specifying additive genetic and unique environmental factors showed the best fit to the data, yielding a heritability of 78-80%. Individual environmental factors explained 18-19% of the variance in this population. Age only accounted for 2-3% of the variance and refractive error and iris colour did not significantly contribute to the variance. CONCLUSIONS: Pupil size after mydriasis is largely genetically determined, with a heritability of up to 80%.


Asunto(s)
Midriáticos/farmacología , Pupila/efectos de los fármacos , Pupila/fisiología , Anciano , Envejecimiento/fisiología , Color del Ojo/fisiología , Femenino , Humanos , Persona de Mediana Edad , Modelos Genéticos , Errores de Refracción/fisiopatología , Gemelos Dicigóticos , Gemelos Monocigóticos
15.
Br J Ophthalmol ; 80(2): 164-7, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8814749

RESUMEN

AIMS/BACKGROUND: Interrupted corneal sutures are used routinely by many cataract and corneal surgeons. A slim compact knot facilitates burial and allows atraumatic suture removal, with decreased risk of wound dehiscence. The size and morphology of knots tied in different configurations were investigated. METHODS: 10-0 nylon suture material was used to tie knots on porcine corneal cataract sections using 2/1/1 (reef and granny), 3/1/1, and 1/1/1/1 (slip knot) configurations. 10-0 Mersilene was used to tie 2/1/1 reef knots. Scanning electron micrographs of the knots were digitised and their maximal lengths and widths estimated. In addition, the area of each knot was calculated and used as an index of its volume. RESULTS: 2/1/1 reef knots were significantly smaller in all dimensions compared with the other knots (all p < 0.03) except for the maximal width of 2/1/1 granny knots which were no wider than the 2/1/1 granny knots. The Mersilene knots were larger than the nylon ones. CONCLUSION: The use of 2/1/1 reef knots is recommended for corneal suturing.


Asunto(s)
Córnea/cirugía , Técnicas de Sutura , Suturas , Animales , Microscopía Electrónica de Rastreo , Porcinos
16.
J Neurosurg ; 95(2 Suppl): 232-5, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11599842

RESUMEN

Long-term survivors of Hodgkin disease may develop second primary tumors caused by the mutagenic effects of radio- and chemotherapy. The authors describe the case of a 35-year-old woman who presented with an unusual meningioma of the cervical spine 9 years after undergoing combined-modality treatment for Hodgkin disease. To the authors' knowledge, this is the first report of spinal meningioma as a complication of such therapy. Whereas radiation-induced intracranial meningiomas are well described in the literature, treatment-induced meningiomas of the spine have not been widely recognized.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Enfermedad de Hodgkin/terapia , Meningioma/etiología , Neoplasias Primarias Secundarias , Neoplasias de la Columna Vertebral/etiología , Adulto , Terapia Combinada/efectos adversos , Femenino , Humanos , Radioterapia/efectos adversos
18.
Equine Vet J ; 18(4): 284-7, 1986 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3758006

RESUMEN

Routine post mortem examination of 195 Thoroughbreds in Hong Kong revealed that 66 per cent suffered from gastric ulceration. Racehorses killed straight out of training suffered a significantly greater incidence of ulceration (80 per cent) than those having been retired for a month or more (52 per cent). The macroscopic findings post mortem enabled a classification of equine gastric ulceration to be suggested (Types 1, 2, 3), according to severity. Severe lesions (Types 2 and 3) were present in 45 per cent of horses put down from training and 5 per cent of retired horses. This difference was significant. Lesions appeared to be chronically progressive during training, but to regress during retirement. The observed difference of gastric ulceration between the two groups of horses was similar for different age groups.


Asunto(s)
Enfermedades de los Caballos/patología , Úlcera Gástrica/veterinaria , Animales , Hong Kong , Enfermedades de los Caballos/epidemiología , Caballos , Úlcera Gástrica/epidemiología , Úlcera Gástrica/patología
19.
Equine Vet J ; 33(5): 478-86, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11558743

RESUMEN

For improvements to the safety and welfare of racehorses to be possible, it is essential to have access to basic descriptive information about the veterinary incidents encountered during horseracing. A 3 year surveillance study (1996-1998) was conducted by The Jockey Club into racing injuries, other postrace clinical problems and fatalities from all 59 British racecourses (mainland Britain only) to identify risk factors. During the survey there were 222,993 racing starts: 106,897 starts in flat races on turf (47.9%), 26,519 starts in flat races on all-weather surfaces (11.9%), 30,932 starts in chases on turf (13.9%), 51,786 starts in hurdle races on turf (23.2%) and 6,859 starts in National Hunt flat races (3.1%). Information was recorded about age of horses, racing surfaces and clinical events observed or attended by a veterinary team of 2 clinicians and one veterinary surgeon employed by the racing authority. Of the 2358 clinical events reported (1.05% of all starts), 1937 involved the musculoskeletal system and 421 involved other body systems. Six hundred and fifty-seven incidents (0.29% of starts) resulted in death or euthanasia. Eighty-one percent of limb injury reports involved forelimbs and 46% involved flexor tendons/suspensory ligaments. Nonlimb problems included epistaxis (0.83/1000 starts), 'exhausted horse syndrome' (0.47/1000 starts) and paroxysmal atrial fibrillation (0.20/1000 starts). Incidents including fatalities per 1000 starts were 24.7 from chases, 19.45 from hurdle races, 8.46 from National Hunt flat races and 3.97 from flat races. The overall tendon injury was higher in chases than in hurdle races, even though age-specific rates of tendon injury were higher in hurdle races than in chases. The risk of injuries per start increased significantly with age, while softer racing surfaces were associated with fewer fatalities and injuries than firmer surfaces. The survey described in this paper has provided an up-to-date description of the fatal and non-fatal horseracing incidents under conditions on mainland Britain, enabling progress to be made towards improving the safety and welfare of racehorses.


Asunto(s)
Bienestar del Animal , Caballos/lesiones , Factores de Edad , Animales , Fibrilación Atrial/veterinaria , Epistaxis/veterinaria , Pisos y Cubiertas de Piso , Incidencia , Traumatismos de la Pierna/veterinaria , Factores de Riesgo , Seguridad , Deportes , Reino Unido , Tiempo (Meteorología)
20.
Int J Obstet Anesth ; 20(4): 282-7, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21852107

RESUMEN

BACKGROUND: Placenta praevia and accreta are leading causes of major obstetric haemorrhage and peripartum hysterectomy. Detection is largely based on a high index of clinical suspicion, though the diagnostic accuracy of radiological imaging is improving. Interventional radiological techniques can reduce blood loss and the incidence of hysterectomy. METHODS: We have reviewed our experience with bilateral prophylactic uterine artery balloon occlusion in the management of women with suspected placenta accreta. Thirteen women at high risk of major haemorrhage due to placenta praevia or suspected placenta accreta were retrospectively studied. Uterine artery balloons were placed prophylactically under neuraxial anaesthesia in the angiography suite followed by caesarean delivery in the obstetric operating theatre. RESULTS: Intraoperative blood loss and transfusion requirements were low in our case series. There were no hysterectomies or admissions to the intensive care unit. Fetal bradycardia necessitating immediate caesarean delivery occurred in two women (15.4%). CONCLUSION: In our case series in women with suspected placenta accreta, prophylactic use of uterine artery balloons was associated with a low requirement for blood transfusion but with possible increased risk of fetal compromise. Performing the interventional procedure at a different site from the operative room complicated management.


Asunto(s)
Oclusión con Balón/métodos , Placenta Accreta/terapia , Adulto , Transfusión Sanguínea , Femenino , Humanos , Imagen por Resonancia Magnética , Embarazo , Estudios Retrospectivos , Arteria Uterina
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA