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1.
Br J Radiol ; 97(1163): 1833-1842, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39152998

RESUMEN

OBJECTIVES: We previously demonstrated the potential of radiomics for the prediction of severe histological placenta accreta spectrum (PAS) subtypes using T2-weighted MRI. We aim to validate our model using an additional dataset. Secondly, we explore whether the performance is improved using a new approach to develop a new multivariate radiomics model. METHODS: Multi-centre retrospective analysis was conducted between 2018 and 2023. Inclusion criteria: MRI performed for suspicion of PAS from ultrasound, clinical findings of PAS at laparotomy and/or histopathological confirmation. Radiomic features were extracted from T2-weighted MRI. The previous multivariate model was validated. Secondly, a 5-radiomic feature random forest classifier was selected from a randomized feature selection scheme to predict invasive placenta increta PAS cases. Prediction performance was assessed based on several metrics including area under the curve (AUC) of the receiver operating characteristic curve (ROC), sensitivity, and specificity. RESULTS: We present 100 women [mean age 34.6 (±3.9) with PAS], 64 of whom had placenta increta. Firstly, we validated the previous multivariate model and found that a support vector machine classifier had a sensitivity of 0.620 (95% CI: 0.068; 1.0), specificity of 0.619 (95% CI: 0.059; 1.0), an AUC of 0.671 (95% CI: 0.440; 0.922), and accuracy of 0.602 (95% CI: 0.353; 0.817) for predicting placenta increta. From the new multivariate model, the best 5-feature subset was selected via the random subset feature selection scheme comprised of 4 radiomic features and 1 clinical variable (number of previous caesareans). This clinical-radiomic model achieved an AUC of 0.713 (95% CI: 0.551; 0.854), accuracy of 0.695 (95% CI 0.563; 0.793), sensitivity of 0.843 (95% CI 0.682; 0.990), and specificity of 0.447 (95% CI 0.167; 0.667). CONCLUSION: We validated our previous model and present a new multivariate radiomic model for the prediction of severe placenta increta from a well-defined, cohort of PAS cases. ADVANCES IN KNOWLEDGE: Radiomic features demonstrate good predictive potential for identifying placenta increta. This suggests radiomics may be a useful adjunct to clinicians caring for women with this high-risk pregnancy condition.


Asunto(s)
Imagen por Resonancia Magnética , Placenta Accreta , Humanos , Femenino , Placenta Accreta/diagnóstico por imagen , Embarazo , Imagen por Resonancia Magnética/métodos , Estudios Retrospectivos , Adulto , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad , Diagnóstico Prenatal/métodos , Curva ROC , Radiómica
2.
J Ultrasound Med ; 32(8): 1471-5, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23887958

RESUMEN

OBJECTIVES: The purpose of this study was to determine the particulate concentration in a gelatin-based ultrasound phantom for lesion biopsy at 6 cm in depth to reduce visualization of the biopsy needle in the near field, simulating subcutaneous fat and tissue echogenicity, and maintain target lesion visualization. METHODS: Four gelatin-based phantoms with cornstarch at concentrations of 4, 8, 12, and 16 g/L and an anechoic gelatin target at 7 cm in depth were rated on a 5-point scale by readers for visibility of the target lesion, similarity of near-field to abdominal subcutaneous fat echogenicity, and visibility of a 22-gauge spinal needle in the phantom. A timed sonographically guided localization task was performed on the anechoic target by 4 radiology residents using the 22-gauge spinal needle. Results were analyzed by comparative statistical analysis. RESULTS: An increasing particulate concentration did not alter the similarity of near-field to abdominal subcutaneous fat echogenicity (P = .6) but did significantly reduce visibility of the anechoic target at a cornstarch concentration of 16 g/L (P = .04) and the 22-gauge needle at 12 g/L (P = .03). Decreased visualization of the needle or target lesion did not affect the time for needle localization of the anechoic target (P = .96). CONCLUSIONS: The optimal ultrasound phantom cornstarch concentration was 12 g/L to reduce visualization of the spinal needle, simulating subcutaneous fat echogenicity while maintaining target lesion visualization.


Asunto(s)
Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico/instrumentación , Gelatina/química , Fantasmas de Imagen , Almidón/química , Diseño de Equipo , Análisis de Falla de Equipo , Gelatina/análisis , Tamaño de la Partícula , Proyectos Piloto , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Almidón/análisis
3.
Case Rep Womens Health ; 37: e00497, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36992812

RESUMEN

Placenta accreta spectrum (PAS) is a rare complication of pregnancy associated with a high risk of massive haemorrhage and caesarean hysterectomy. This is a case report of abdominal aortic balloon occlusion, using intravascular ultrasound, to achieve uterine conservation in a case of severe PAS. The patient was a 34-year-old woman, G2P1, with one prior caesarean section. Antenatal imaging, consisting of transabdominal and transvaginal ultrasound, and magnetic resonance imaging, showed features of PAS. The risk of caesarean hysterectomy with PAS was explained, but the patient declared a desire to retain fertility. Following multi-disciplinary discussion, it was considered appropriate to attempt uterine conservation using en-bloc myometrial and placental resection. An elective caesarean delivery was performed at 36 weeks of gestation. An aortic balloon was inserted prior to surgery using intravascular ultrasound, which allowed for radiation-free, point-of-surgery, accurate balloon sizing, by measuring the aortic diameter, and correct placement of the balloon in the abdominal aorta below the renal vessels. Intraoperative findings confirmed PAS, and a myometrial resection was performed. There were no intraoperative complications. Estimated blood loss was 1000 mL and the patient had an uncomplicated postoperative course. This case demonstrates how the use of an intravascular intraoperative aortic balloon can facilitate uterine conservation in a case of severe PAS.

4.
Eur Radiol Exp ; 7(1): 54, 2023 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-37726591

RESUMEN

BACKGROUND: Placenta accreta spectrum (PAS) is a rare, life-threatening complication of pregnancy. Predicting PAS severity is critical to individualise care planning for the birth. We aim to explore whether radiomic analysis of T2-weighted magnetic resonance imaging (MRI) can predict severe cases by distinguishing between histopathological subtypes antenatally. METHODS: This was a bi-centre retrospective analysis of a prospective cohort study conducted between 2018 and 2022. Women who underwent MRI during pregnancy and had histological confirmation of PAS were included. Radiomic features were extracted from T2-weighted images. Univariate regression and multivariate analyses were performed to build predictive models to differentiate between non-invasive (International Federation of Gynecology and Obstetrics [FIGO] grade 1 or 2) and invasive (FIGO grade 3) PAS using R software. Prediction performance was assessed based on several metrics including sensitivity, specificity, accuracy and area under the curve (AUC) at receiver operating characteristic analysis. RESULTS: Forty-one women met the inclusion criteria. At univariate analysis, 0.64 sensitivity (95% confidence interval [CI] 0.0-1.00), specificity 0.93 (0.38-1.0), 0.58 accuracy (0.37-0.78) and 0.77 AUC (0.56-.097) was achieved for predicting severe FIGO grade 3 PAS. Using a multivariate approach, a support vector machine model yielded 0.30 sensitivity (95% CI 0.18-1.0]), 0.74 specificity (0.38-1.00), 0.58 accuracy (0.40-0.82), and 0.53 AUC (0.40-0.85). CONCLUSION: Our results demonstrate a predictive potential of this machine learning pipeline for classifying severe PAS cases. RELEVANCE STATEMENT: This study demonstrates the potential use of radiomics from MR images to identify severe cases of placenta accreta spectrum antenatally. KEY POINTS: • Identifying severe cases of placenta accreta spectrum from imaging is challenging. • We present a methodological approach for radiomics-based prediction of placenta accreta. • We report certain radiomic features are able to predict severe PAS subtypes. • Identifying severe PAS subtypes ensures safe and individualised care planning for birth.


Asunto(s)
Placenta Accreta , Embarazo , Humanos , Femenino , Placenta Accreta/diagnóstico por imagen , Estudios Prospectivos , Estudios Retrospectivos , Aprendizaje Automático , Proyectos de Investigación
5.
Can Urol Assoc J ; 15(11): E569-E573, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33999803

RESUMEN

INTRODUCTION: Varicocele is a relatively common condition in men that causes pain in approximately 10% of cases. There have been few studies to date assessing the improvements in both pain and quality of life parameters associated with spermatic vein embolization (SVE) as a treatment for patients with symptomatic varicocele, so we aimed to assess this. METHODS: A review was carried out of consecutive SVE procedures performed at our institution from 2013-2019. Only patients with painful varicocele were included after other causes of testicular pain were excluded. The technique employed was a combination of distal coil embolization of the spermatic vein with 4-6 mm coils at the level of the inguinal canal, as well as sclerotherapy to prevent reflux of sclerosant. Furthermore, a prospective validated Pain Impact Questionnaire-6 (PIQ-6) was performed to assess for improvement in quality of life. A matched pair Student two-tailed t-test was used to compare mean scores pre- and post-treatment, with 95% confidence intervals presented as T scores and their associated p-values. RESULTS: Over six years, 62 SVE procedures were performed for symptomatic varicocele. Success rate was 95%, with a median followup of nine months. Two patients had a failed procedure on two occasions requiring subsequent surgical ligation. There was one clinically significant recurrence. All components of PIQ-6 score showed a statistically significant reduction post-SVE, most noticeably pain severity and impact on leisure activities. CONCLUSIONS: SVE is a safe, effective, and well-tolerated treatment for symptomatic varicocele, improving pain and quality of life.

6.
Can J Surg ; 52(3): 201-6, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19503664

RESUMEN

BACKGROUND: Predicting the clinical course in adhesional small bowel obstruction is difficult. There are no validated clinical or radiologic features that allow early identification of patients likely to require surgical intervention. METHODS: We conducted a retrospective review of 100 patients consecutively admitted to a tertiary level teaching hospital over a 3-year period (2002-2004) who had acute adhesional small bowel obstruction and underwent computed tomography (CT). The primary outcomes that we assessed were conservative management or the need for surgical intervention. We investigated time to physiologic gastrointestinal function recovery as a secondary outcome. We examined independent predictors of surgical intervention in a bivariate analysis using a stepwise logistic regression analysis. RESULTS: Of the 100 patients investigated, we excluded 12. Of the 88 remaining patients, 58 (66%) were managed conservatively and 30 (34%) underwent surgery. Peritoneal fluid detected on a CT scan (n = 37) was associated more frequently with surgery than conservative management (46% v. 29%, p = 0.046, chi(2)). Logistical regression identified peritoneal fluid detected on a CT scan as an independent predictor of surgical intervention (odds ratio 3.0, 95% confidence interval 1.15-7.84). CONCLUSION: The presence of peritoneal fluid on a CT scan in patients with adhesional small bowel obstruction is an independent predictor of surgical intervention and should alert the clinician that the patient is 3 times more likely to require surgery.


Asunto(s)
Líquido Ascítico/diagnóstico por imagen , Obstrucción Intestinal/diagnóstico por imagen , Obstrucción Intestinal/cirugía , Intestino Delgado , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Tránsito Gastrointestinal , Humanos , Obstrucción Intestinal/complicaciones , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Recuperación de la Función , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
9.
Vasc Endovascular Surg ; 51(5): 274-281, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28639918

RESUMEN

PURPOSE: To assess rates of complications, secondary interventions, survival, and cause of death following endovascular abdominal aortic aneurysm (AAA) repair over a 10-year period. MATERIALS AND METHODS: Single-institution retrospective cohort study of all patients undergoing primary endovascular aortic aneurysm repair (EVAR) between July 2006 and June 2015. The population constituted 175 patients with 163 fusiform and 12 saccular AAAs. Of these, 149 (85%) were male, with mean age 75.4 (±7.1) years. Patients were followed up until June 30, 2016. Cause of death was determined from the national death register. RESULTS: Mean follow-up was 34.4 (±24.4) months. The secondary intervention rate was 9.7%, and there were 4 aneurysm ruptures (0.8% annual incidence). Thirty-day mortality was 0.6%. Survival at 1, 3, and 5 years was 93.1%, 84%, and 64.9%, respectively. Forty-eight patients died during follow-up, 3 secondary to rupture, leading to overall and aneurysm-related death rates of 9.7 and 0.6 per 100 person-years. All other deaths were due to nonaneurysm causes, most commonly cardiovascular (n = 15), pulmonary (n = 13), and malignancy (n = 9). Baseline renal impairment ( P < .001), ischemic heart disease ( P < .05), age greater than 75 years ( P < .05), and urgent/emergency EVAR were associated with inferior long-term survival. Type II endoleak negatively influenced fusiform aneurysm sac regression ( P = .02), but there was no association between survival and occurrence of any complication or secondary intervention. CONCLUSION: The majority of deaths during medium-term follow-up post-EVAR are due to nonaneurysm-related causes. Survival is determined by the following baseline factors: renal impairment, ischemic heart disease, advanced age, and the presence of a symptomatic/ruptured aneurysm.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Anciano , Anciano de 80 o más Años , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/mortalidad , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/mortalidad , Causas de Muerte , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/mortalidad , Femenino , Humanos , Irlanda , Estimación de Kaplan-Meier , Masculino , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
10.
Diagn Interv Radiol ; 23(6): 441-447, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29063856

RESUMEN

PURPOSE: We aimed to compare the overall (OS) and disease-free survival (DFS) of patients undergoing orthotopic liver transplant (OLT) for hepatocellular carcinoma who did and did not have neoadjuvant doxorubicin drug-eluting bead transarterial chemoembolization (DEB-TACE). METHODS: This is a retrospective study of 94 patients with HCC transplanted between 2000 and 2014 in a single tertiary center. Pre- and postoperative features, DFS and OS were compared between patients who received pre-OLT DEB-TACE (n=34, DEB-TACE group) and those who did not (n=60, non-TACE group). Radiologic and histologic response to neoadjuvant treatment as well as its complications were also studied. RESULTS: There were no significant differences in post-transplantation DFS and OS rates between groups (5-year DFS: 70% in DEB-TACE group vs. 63% in non-TACE group, P = 0.454; 5-year OS: 70% in DEB-TACE group vs. 65% in non-TACE group, P = 0.532). The DEB-TACE group had longer OLT waiting time compared with the non-TACE group (110 vs. 72 days; P = 0.01). On univariate and multivariate analyses, alpha-fetoprotein (AFP) levels >500 ng/mL prior to OLT were associated with decreased OS and DFS regardless of neoadjuvant approach (hazard ratio of 6, P = 0.001 and 5.5, P = 0.002, respectively). CONCLUSION: Patients who underwent neoadjuvant DEB-TACE and OLT for hepatocellular carcinoma had no statistically different OS or DFS at 3 and 5 years from patients undergoing OLT alone.


Asunto(s)
Carcinoma Hepatocelular/terapia , Quimioembolización Terapéutica/métodos , Doxorrubicina/uso terapéutico , Neoplasias Hepáticas/terapia , Trasplante de Hígado , Terapia Neoadyuvante/métodos , Antibióticos Antineoplásicos/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/cirugía , Supervivencia sin Enfermedad , Femenino , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/cirugía , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
13.
Ann Med Surg (Lond) ; 4(1): 76-9, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25834731

RESUMEN

INTRODUCTION: Acute mesenteric ischaemia (AMI) continues to have a high mortality, ranging from 60 to 80%. PRESENTATION OF CASE: A 78-year-old male presented with a 20-hour history of abdominal pain, secondary to a superior mesenteric artery (SMA) thromboembolic occlusion diagnosed on computed tomography (CT) angiography. Following confirmation of bowel viability at laparotomy, endovascular intervention using combined thrombolysis, angioplasty and thromboaspiration was performed. Despite successful recanalisation of the occlusion, his condition continued to deteriorate fatally due to progressive sepsis. DISCUSSION: We discuss the role of biphasic CT in diagnosis of AMI, and review the evidence for endovascular interventions now increasingly used in the emergent management of thromboembolic AMI. CONCLUSION: Early diagnosis using CT angiography is essential, as it is highly sensitive in detecting a visceral arterial occlusion. However, laparotomy is often required to accurately determine bowel viability and the need for resection. Endovascular interventions appear to be effective alternatives to open surgery with appropriate patient selection.

14.
Endocrine ; 44(2): 504-9, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23471696

RESUMEN

According to the international guidelines, a multidisciplinary approach is currently advised for the optimal care of patients with a gastroenteropancreatic neuroendocrine tumor (GEP NET). In our institution (tertiary care center), a systematic multidisciplinary approach was established in May 2007. In this study, we have aimed to assess the initial impact of establishing a systematic multidisciplinary approach to the management of GEP NET patients. We have collected and compared the biochemical, imaging, and pathological data and the therapeutic strategies in GEP NET patients diagnosed, treated, or followed-up from January 1993 to April 2007 versus GEP NET patients attending our institution after the multidisciplinary approach starting, from May 2007 to October 2008. Data of 91 patients before and 42 patients after the establishment of the multidisciplinary approach (total: 133 consecutive GEP NET patients) have been finally collected and analyzed. Before the establishment of the multidisciplinary approach, a lack of consistency in the biochemical, imaging, and pathological findings before treatment initiation as well as during follow-up of GEP NET patients was identified. These inconsistencies have been reduced by the systematic multidisciplinary approach. In addition, the therapeutic management of GEP NET patients has been altered by the multidisciplinary approach and became more consistent with recommended guidelines. We think that a systematic multidisciplinary approach significantly impacts on GEP NET patient care and should be established in all centers dealing with these tumors.


Asunto(s)
Comunicación Interdisciplinaria , Neoplasias Intestinales/diagnóstico , Neoplasias Intestinales/terapia , Tumores Neuroendocrinos/diagnóstico , Tumores Neuroendocrinos/terapia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/terapia , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Terapia Combinada/estadística & datos numéricos , Femenino , Humanos , Neoplasias Intestinales/epidemiología , Masculino , Persona de Mediana Edad , Tumores Neuroendocrinos/epidemiología , Neoplasias Pancreáticas/epidemiología , Grupo de Atención al Paciente , Pronóstico , Neoplasias Gástricas/epidemiología , Resultado del Tratamiento , Adulto Joven
16.
Am J Surg ; 200(4): e51-2, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20887834

RESUMEN

Acute aortic plaque rupture is an uncommon cause of acute lower limb ischemia. The authors report sequence computed tomographic imaging of a distal aortic plaque rupture in a young man with bilateral lower limb complications. Clinical awareness, prompt recognition and imaging, and appropriate treatment of this uncommon condition are necessary to improve patient outcomes.


Asunto(s)
Aneurisma Roto/complicaciones , Aneurisma de la Aorta Abdominal/complicaciones , Embolia/complicaciones , Claudicación Intermitente/etiología , Arteria Poplítea , Enfermedad Aguda , Adulto , Aneurisma Roto/diagnóstico por imagen , Aneurisma Roto/cirugía , Angiografía , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/cirugía , Aortografía , Diagnóstico Diferencial , Embolectomía/métodos , Embolia/diagnóstico por imagen , Embolia/terapia , Humanos , Claudicación Intermitente/diagnóstico por imagen , Claudicación Intermitente/terapia , Masculino , Terapia Trombolítica/métodos , Tomografía Computarizada por Rayos X
18.
Radiology ; 224(1): 225-30, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12091687

RESUMEN

PURPOSE: To determine if cardiac pulsations are visible and quantifiable on spectral waveforms during Doppler ultrasonographic (US) evaluation of transjugular intrahepatic portosystemic shunts (TIPS), and if so, whether their magnitude declines with shunt dysfunction. MATERIALS AND METHODS: Baseline and pre-revision US images obtained in 15 patients with venographically confirmed TIPS malfunction were retrospectively examined for spectral waveform pulsation. Cardiac pulsatility was quantified by using the venous pulsatility index (VPI), the venous equivalent of resistive index. VPIs were obtained at four locations from the main portal vein to the stent-hepatic venous junction. Baseline and follow-up examination results in 11 patients with functional TIPS acted as controls and were evaluated similarly. Baseline and follow-up mean VPIs at all four locations were compared for both sets of patients by using the Newman-Keuls pairwise multiple sample comparison test. The chi(2) test was used to determine if a VPI threshold that would result in an acceptable sensitivity and specificity for shunt dysfunction existed. RESULTS: One hundred twenty mean VPIs were obtained in the study group, and 88 mean VPIs were obtained in the control group. Pre-revision VPIs at each location were significantly lower (P <.01) than all baseline values and than the follow-up values in the control group. A VPI less than 0.16 was 94% sensitive and 87% specific for shunt dysfunction. CONCLUSION: The VPI, a quantitative measure of cardiac pulsation obtained with Doppler US, may be a useful parameter for assessing TIPS function.


Asunto(s)
Derivación Portosistémica Intrahepática Transyugular , Pulso Arterial , Ultrasonografía Doppler , Anciano , Anciano de 80 o más Años , Femenino , Corazón/fisiología , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Sensibilidad y Especificidad
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