Deep learning method for aortic root detection.

BACKGROUND: Computed tomography angiography (CTA) is a preferred imaging technique for a wide range of vascular diseases. However, extensive manual analysis is required to detect and identify several anatomical landmarks for clinical application. This study demonstrates the feasibility of a fully automatic method for detecting the aortic root, which is a key anatomical landmark in this type of procedure. The approach is based on the use of deep learning techniques that attempt to mimic expert behavior. METHODS: A total of 69 CTA scans (39 for training and 30 for validation) with different pathology types were selected to train the network. Furthermore, a total of 71 CTA scans were selected independently and applied as the test set to assess their performance. RESULTS: The accuracy was evaluated by comparing the locations marked by the method with benchmark locations (which were manually marked by two experts). The interobserver error was 4.6 ± 2.3 mm. On an average, the differences between the locations marked by the two experts and those detected by the computer were 6.6 ± 3.0 mm and 6.8 ± 3.3 mm, respectively, when calculated using the test set. CONCLUSIONS: From an analysis of these results, we can conclude that the proposed method based on pre-trained CNN models can accurately detect the aortic root in CTA images without prior segmentation.

Automatic detection of anatomical landmarks of the aorta in CTA images.

Computed tomography angiography (CTA) is one of the most common vascular imaging modalities. However, for clinical use, it still requires laborious manual analysis. This study demonstrates the feasibility of a fully automated technology for the accurate detection and identification of several anatomical reference points (landmarks), commonly used in intravascular imaging. This technology uses two different approaches, specially designed for the detection of aortic root and supra-aortic and visceral branches. In order to adjust the parameters of the developed algorithms, a total of 33 computed tomography scans with different types of pathologies were selected. Furthermore, a total of 30 independently selected computed tomography scans were used to assess their performance. Accuracy was evaluated by comparing the locations of reference points manually marked by human experts with those that were automatically detected. For supra-aortic and visceral branches detection, average values of 91.8 % for recall and 98.8 % for precision were obtained. For aortic root detection, the average difference between the positions marked by the experts and those detected by the computer was 5.7 ± 7.3 mm. Finally, diameters and lengths of the aorta were measured at different locations related to the extracted landmarks. Those measurements agreed with the values reported by the literature. Graphical abstract Schematic description of the proposed algorithm. The input includes an already segmented aorta (left), there are two main sub-processes related to the detection of branches and roots (center), and the output includes the segmented original aorta with the branches and the detected landmarks superimposed (right).

Automatic estimation of the aortic lumen geometry by ellipse tracking.

PURPOSE: The shape and size of the aortic lumen can be associated with several aortic diseases. Automated computer segmentation can provide a mechanism for extracting the main features of the aorta that may be used as a diagnostic aid for physicians. This article presents a new fully automated algorithm to extract the aorta geometry for either normal (with and without contrast) or abnormal computed tomography (CT) cases. METHODS: The algorithm we propose is a fast incremental technique that computes the 3D geometry of the aortic lumen from an initial contour located inside it. Our approach is based on the optimization of the 3D orientation of the cross sections of the aorta. The method uses a robust ellipse estimation algorithm and an energy-based optimization technique to automatically track the centerline and the cross sections. The optimization involves the size and eccentricity of the ellipse which best fits the aorta contour on each cross-sectional plane. The method works directly on the original CT and does not require a prior segmentation of the aortic lumen. We present experimental results to show the accuracy of the method and its ability to cope with challenging CT cases where the aortic lumen may have low contrast, different kinds of pathologies, artifacts, and even significant angulations due to severe elongations. RESULTS: The algorithm correctly tracked the aorta geometry in 380 of 385 CT cases. The mean of the dice similarity coefficient was 0.951 for aorta cross sections that were randomly selected from the whole database. The mean distance to a manually delineated segmentation of the aortic lumen was 0.9 mm for sixteen selected cases. CONCLUSIONS: The results achieved after the evaluation demonstrate that the proposed algorithm is robust and accurate for the automatic extraction of the aorta geometry for both normal (with and without contrast) and abnormal CT volumes.

Quality of life as assessed by adults with cerebral palsy.

AIM: We explored the quality of life of adults with cerebral palsy without an intellectual disability and the predictors of quality of life. BACKGROUND: Because cerebral palsy is a disease that manifests in childhood, much of the research into quality of life for those dealing with it focuses on children; there are few studies that evaluate the quality of life of adults with cerebral palsy. Therefore, it is important to consider their perceptions in order to improve their general wellbeing and self-determination. DESIGN: This was a descriptive, cross-sectional study. METHOD: Quality of life was measured using the GENCAT Quality of Life Scale. Demographic and personal variables were also collected and examined. Participants comprised 75 adults (58.7 percent men, mean age = 40.84 years) with cerebral palsy who were members of the National Cerebral Palsy Association of Spain between 2014 and 2015. A linear multivariate model was examined as well. RESULTS: The overall mean score indicator of participants' quality of life was 103.29, which corresponds to the 56.6th percentile on the GENCAT scale. Examining the level of qualification, we found significant differences in the factors "personal development" and "self-determination," and those with a university education obtained higher scores than their less-educated counterparts. Having a partner was related to higher quality of life standard scores. After constructing a linear model, it was observed that maintaining sexual relationships was another factor that increased participants' quality of life. CONCLUSION: This study highlights the importance of social and romantic relationships to achieve a better quality of life in adults with cerebral palsy who do not have an intellectual disability. Social integration and sexuality education programs should be developed to improve their quality of life.

Automatic characterization of thoracic aortic aneurysms from CT images.

Accurate determination of the diameter is an important step for diagnosis and follow-up of aortic abnormalities such as aneurysms, caused by dilation of the vessel lumen. In this work we focus on the development of an automatic method for measuring the calibre of the thoracic aorta. The method is based on the application of principal component analysis on normal planes extracted from the aorta to establish the main axis of each section of the vessel. Two experiments were performed in order to test the accuracy and the rotational invariance of the developed method. Accuracy was determined by using a database of 15 clinical cases, where our method and a commercial software, which was considered as the gold standard, were compared. For the rotational invariance check, phantom images in different orientations were obtained and the diameter was measured with the proposed method. For clinical cases, a good agreement was observed between our method and the gold standard. The Bland Altman plots indicated that all of the values were within the acceptable limits of agreement with a bias of 0.2mm between both methods. For phantom cases, an ANOVA test revealed that the results achieved for the data sets acquired for the different orientations were not statistically different (F=1.88, p=0.153), which demonstrates the robustness of the method for rotations. The proposed method is applicable for measuring the diameter in all tested cases, and the results achieved underscored the capability of our approach for automatic characterization of thoracic aortic aneurysms.

Semi-automatic segmentation and detection of aorta dissection wall in MDCT angiography.

Aorta dissection is a serious vascular disease produced by a rupture of the tunica intima of the vessel wall that can be lethal to the patient. The related diagnosis is strongly based on images, where the multi-detector CT is the most generally used modality. We aim at developing a semi-automatic segmentation tool for aorta dissections, which will isolate the dissection (or flap) from the rest of the vascular structure. The proposed method is based on different stages, the first one being the semi-automatic extraction of the aorta centerline and its main branches, allowing an subsequent automatic segmentation of the outer wall of the aorta, based on a geodesic level set framework. This segmentation is then followed by an extraction the center of the dissected wall as a 3D mesh using an original algorithm based on the zero crossing of two vector fields. Our method has been applied to five datasets from three patients with chronic aortic dissection. The comparison with manually segmented dissections shows an average absolute distance value of about half a voxel. We believe that the proposed method, which tries to solve a problem that has attracted little attention to the medical image processing community, provides a new and interesting tool to isolate the intimal flap that can provide very useful information to the clinician.

A hybrid method based on level set and 3D region growing for segmentation of the thoracic aorta.

This study sought to develop a completely automatic method for image segmentation of the thoracic aorta. We used a total of 4682 images from 10 consecutive patients. The proposed method is based on the use of level set and region growing, automatically initialized using the Hough transform. The results obtained were compared to those of manual segmentation as performed by an external expert radiologist. Concordance between the developed method and manual segmentation ranged from 92.79 to 95.77% in the descending regions of the aorta and from 90.68 to 96.54% in the ascending regions, with a mean value of 93.83% being obtained for total segmentation.

Impacto do tabagismo parental sobre a asma infantil / Impact of parental smoking on childhood asthma

OBJETIVO: Avaliar a exposição da população infantil à FCA em nossa comunidade e sua relação com os sintomas de asma. MÉTODOS: Foi realizado um estudo transversal usando o questionário de estudo ISAAC em crianças e adolescentes da nossa comunidade. Pelo questionário, fez-se a definição por "já ocorreu sibilância", "asma atual", "asma grave" e "asma induzida pelo exercício". O tabagismo parental foi classificado em quatro categorias mutuamente excludentes: 1) nenhum dos pais fuma; 2) somente a mãe fuma; 3) somente o pai fuma; e 4) ambos os pais fumam. Calculou-se a odds ratio da prevalência de sintomas de asma, de acordo com a exposição à FCA, usando regressão logística. RESULTADOS: Foram incluídas, no total, 10.314 crianças e 10.453 adolescentes. Mais de 51% das crianças e adolescentes foram expostos à FCA em casa. A FCA se associa a uma prevalência mais alta de sintomas de asma, particularmente se a mãe ou ambos os pais fumam. CONCLUSÕES: A prevalência da FCA continua a ser alta em nossa comunidade, embora com uma tendência para diminuição nos últimos 15 anos. A FCA se associa a uma prevalência mais alta de asma.

OBJETIVE: To evaluate the exposure to environmental tobacco smoke (ETS) of the childhood population in this community and its relationship with asthma symptoms. METHODS: A cross-sectional study was conducted using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire on children and adolescents in this community. The symptoms "wheezing ever", "current asthma", "severe asthma", and "exercise-induced asthma" were defined by this questionnaire. Parental smoking was classified into four mutually exclusive categories: 1) no parent smokes; 2) only the mother smokes; 3) only the father smokes; and 4) both parents smoke. The odds ratio of the prevalence of asthma symptoms according to ETS exposure was calculated using logistic regression. RESULTS: A total of 10,314 children and 10,453 adolescents were included. Over 51% of the children and adolescents were exposed to ETS at home. ETS is associated with a higher prevalence of asthma symptoms, particularly if the mother or both parents smoke. CONCLUSION: The prevalence of ETS is still high in this community, although there has been a decreasing tendency in the last 15 years. ETS is associated with higher prevalence of asthma.

Impact of parental smoking on childhood asthma.

OBJECTIVE: To evaluate the exposure to environmental tobacco smoke (ETS) of the childhood population in this community and its relationship with asthma symptoms. METHODS: A cross-sectional study was conducted using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire on children and adolescents in this community. The symptoms "wheezing ever", "current asthma", "severe asthma", and "exercise-induced asthma" were defined by this questionnaire. Parental smoking was classified into four mutually exclusive categories: 1) no parent smokes; 2) only the mother smokes; 3) only the father smokes; and 4) both parents smoke. The odds ratio of the prevalence of asthma symptoms according to ETS exposure was calculated using logistic regression. RESULTS: A total of 10,314 children and 10,453 adolescents were included. Over 51% of the children and adolescents were exposed to ETS at home. ETS is associated with a higher prevalence of asthma symptoms, particularly if the mother or both parents smoke. CONCLUSION: The prevalence of ETS is still high in this community, although there has been a decreasing tendency in the last 15 years. ETS is associated with higher prevalence of asthma.

[Hemodynamic depression in carotid artery stent without angioplasty]. / Incidencia de la depresion hemodinamica en el implante de endoprotesis en la arteria carotida sin dilatacion.

INTRODUCTION: Hemodynamic depression is a frequent complication related to carotid artery stenting with angioplasty. The aim of this study was to assess our results regarding hemodynamic depression, in patients who underwent carotid artery stenting without angioplasty. PATIENTS AND METHODS: Between October 2002 and April 2010, 261 carotid stenosis (in 242 patients) were treated with the use of self-expanding stents without angioplasty. Inclusion criteria were symptomatic carotid stenosis > 50%, asymptomatic carotid stenosis > 70%, and stenosis ranging between 50-70% with evidence of high risk plaque morphology or micro-embolism. Outcomes during hospitalization and 30 days after procedure were registered. Hemodynamic depression was defined as hypotension (systolic blood pressure < 90 mm Hg) or bradycardia (heart rate < 60 beats/min). RESULTS: During the procedure 7 (2.9%) patients presented bradycardia and 3 (1.2%) hypotension. No patient required vasopressor drugs or ICU for hemodynamic monitoring. No patient developed asystole or other types of arrhythmia. During hospitalization, hemodynamic depression was not observed in any patients. During the first 30 days post-procedure, there were 11 TIAs (4.5%), 1 disabling stroke (0.4%), 1 non disabling stroke (0.4%), and 1 death (0.4%) (1 stent thrombosis at 11 days). CONCLUSION: The incidence of hemodynamic depression is low when carotid stenting procedure is performed without balloon angioplasty. The incidence of neurological complications post procedure was also low. This report highlights the need for performing randomized trials comparing both techniques.

Incidencia de la depresión hemodinámica en el implante de endoprótesis en la arteria carótida sin dilatación / Hemodynamic depression in carotid artery stent without angioplasty

Introducción. La depresión hemodinámica es una complicación frecuente tras el implante de una endoprótesis carotídea con angioplastia. El objetivo del estudio es evaluar la incidencia de depresión hemodinámica en pacientes sometidos al implante de endoprótesis carotídea sin angioplastia. Pacientes y métodos. Entre octubre de 2002 y abril de 2010, se trataron 261 estenosis carotídeas (242 pacientes) con endoprótesis autoexpandibles sin angioplastia. Los criterios de inclusión fueron estenosis carotídea sintomática > 50%, estenosis carotídea asintomática > 70%, estenosis entre el 50-70% y evidencia de alto riesgo de microembolismo por la morfología de la placa de ateroma. Se evaluó a los pacientes al ingreso y 30 días después del procedimiento. La depresión hemodinámica se definió como hipotensión (presión arterial sistólica < 90 mmHg) o bradicardia (pulso < 60 lpm). Resultados. Durante el procedimiento, siete pacientes (2,9%) presentaron bradicardia y tres (1,2%), hipotensión. Ninguno de ellos necesitó medicación o monitorización. No se observó asistolia u otro tipo de arritmia en ningún paciente. Durante la hospitalización, no se observó depresión hemodinámica en ningún paciente. En los 30 primeros días después del procedimiento se produjeron 11 ataques isquémicos transitorios (4,5%), un ictus incapacitante (0,4%), un ictus no incapacitante (0,4%) y un fallecimiento (0,4%) (por trombosis de la endoprótesis a los 11 días). Conclusiones. La incidencia de depresión hemodinámica y de complicaciones neurológicas es baja en pacientes sometidos a implante de endoprótesis en la arteria carótida sin angioplastia con balón. Este estudio subraya la necesidad de realizar ensayos aleatorios que comparen ambas técnicas con y sin angioplastia(AU)

Introduction. Hemodynamic depression is a frequent complication related to carotid artery stenting with angioplasty. The aim of this study was to assess our results regarding hemodynamic depression, in patients who underwent carotid artery stenting without angioplasty. Patients and methods. Between October 2002 and April 2010, 261 carotid stenosis (in 242 patients) were treated with the use of self-expanding stents without angioplasty. Inclusion criteria were symptomatic carotid stenosis > 50%, asymptomatic carotid stenosis > 70%, and stenosis ranging between 50-70% with evidence of high risk plaque morphology or microembolism. Outcomes during hospitalization and 30 days after procedure were registered. Hemodynamic depression was defined as hypotension (systolic blood pressure < 90 mm Hg) or bradycardia (heart rate < 60 beats/min). Results. During the procedure 7 (2.9%) patients presented bradycardia and 3 (1.2%) hypotension. No patient required vasopressor drugs or ICU for hemodynamic monitoring. No patient developed asystole or other types of arrhythmia. During hospitalization, hemodynamic depression was not observed in any patients. During the first 30 days post-procedure, there were 11 TIAs (4.5%), 1 disabling stroke (0.4%), 1 non disabling stroke (0.4%), and 1 death (0.4%) (1 stent thrombosis at 11 days). Conclusion. The incidence of hemodynamic depression is low when carotid stenting procedure is performed without balloon angioplasty. The incidence of neurological complications post procedure was also low. This report highlights the need for performing randomized trials comparing both techniques(AU)

Exposure to paracetamol and asthma symptoms.

BACKGROUND: Paracetamol is one of the factors that have been associated with the observed increase in asthma prevalence in the last few years. The influence of environmental or genetic factors in this disease may be different in some countries than in others. The purpose of this study was to analyse the relationship between the paracetamol consumption and asthma prevalence in our community. METHODS: A cross-sectional study was conducted on more than 20,000 children and adolescents in Galicia, Spain. The International Study of Asthma and Allergies in Childhood methodology was used to collect the information on asthma symptoms in children, paracetamol consumption, body mass index (BMI), pets in the home, education level of the mother and parental asthma and smoking habits. The influence of paracetamol consumption on the prevalence of asthma symptoms was calculated using logistic regression, adjusted for the other parameters included in the study. RESULTS: After adjusting for gender, BMI, having a cat or dog, maternal education, parental asthma and smoking, in 6- to 7-year-old children, the consumption of paracetamol during the first year of life is associated with asthma [odds ratio (OR) 2.04 (1.79-2.31) for wheezing at some time]. Paracetamol consumption in the previous year leads to a significant increase in the probability of wheezing at some time [OR 3.32 (2.51-4.41)] in young children and adolescents [OR 2.12 (1.68-2.67)]. CONCLUSIONS: Paracetamol consumption is associated with a significant increase in asthma symptoms. The effect is greater the more often the drug is taken.

Trends in adult asthma hospitalization: gender-age effect.

BACKGROUND: Hospital admissions due to asthma are a reliable source of information on the morbidity of the disease which, after the increase observed in the last quarter of the last century, shows a declining trend in the last few years. The aim of this study was to look at hospital admission trends due to asthma in our community and analyze some of its associated factors. METHODS: Retrospective analysis of all hospital admissions involving adults aged 15 years and older with asthma as the primary or secondary diagnosis (if the first diagnosis was respiratory failure or respiratory infection) in Public Health Service hospitals in the Galician region of Spain between the years 1995-2009 (total 24,766 admissions). RESULTS: The majority of patients admitted were female (71%), over 60 years of age (64%), and admission occurred predominantly in the winter months. The hospitalization rate due to asthma tripled over the period studied, this being mainly accounted for by women aged over 60 years. Mean hospital stay was 9.2 days, longer in older patients or those admitted over the weekend. CONCLUSIONS: A significant increase in hospital admissions due to asthma over the last few years has been observed in our community, mainly involving older women. The mean stay seems long, increasing with patients' age and admission over the weekend.

Endovascular treatment of an acutely ruptured intracranial aneurysm in pregnancy: report of eight cases.

Treatment of acutely ruptured intracranial aneurysms in pregnancy represents a clinical challenge requiring a meticulously selected strategy. We report eight cases of ruptured cerebral aneurysms in eight pregnant patients treated safely and effectively via an endovascular approach.

Adecuación del aislamiento respiratorio e influencia del tratamiento en lamicrobiología del esputo en pacientes con tuberculosis / No disponible

Objetivo: Evaluar la adecuación del aislamiento y la respuesta microbiológica al tratamiento en pacientes con tuberculosis (TB).Métodos: Determinaciones: 1. Adecuación del aislamiento: hospitalario (sospecha diagnóstica y aislamiento desde la admisión en la planta de hospitalización) o domiciliario (diagnóstico y tratamiento tras el alta en urgencias y aislamiento en el domicilio 15 días). 2. Influencia del tratamiento en el estado bacteriológico del esputo. Resultados: 1. De 100 pacientes consecutivos con TB, 50 tenían baciloscopia +, 37 de ellos tenían aislamiento correcto (28 hospitalario, 9 domiciliario). En los 13 restantes el aislamiento fue incorrecto,3 domiciliario (dos alta sin aislamiento y retraso diagnóstico de 7 y 10 días, otro con aislamiento 10días) y 10 ingresados (retraso de 1-14 días, media 4.5; en 5 retraso de un día y en los 5 restantes retraso de 3 a 14 días). 2. De 50 pacientes con baciloscopia + en 14 se realizó control microbiológicoal mes del inicio del tratamiento (todos baciloscopia +, 10 cultivo +). En 25 con control al 2º mes, 8baciloscopia +, 7 Cultivo +.Conclusiones: 1. Se ha objetivado que en el 13% de los pacientes con TB no se realizó el aislamiento correctamente. 2. En pacientes con TB bacilífera, tras uno o dos meses de tratamiento existe un número importante con baciloscopia y cultivo +. Se deben controlar la política de aislamiento y la respuesta microbiológica al tratamiento por la influencia que pueden tener en la transmisión de la TB (AU)

Aim: To know 1º. The respiratory isolation policy, 2º. The effect of treatment on the sputum bacteriologic status in patients with tuberculosis (TB).Methods: 1. Description of isolation policies. We defined correct isolation in hospital as diagnosis suspicion and isolation on admission and duration no less than 15 days and correct domiciliary isolation as diagnosis in emergency room with recommendation of treatment and stay at home at least 15days. 2. Follow-up of sputum status after treatment. Results: 1. 100 consecutive patients, sputum smear + in 50, 37 with correct isolation (28 in hospital and 9 domiciliary). In 13 with incorrect isolation, 3 were outpatients (2 without diagnosis neither isolation and delay in diagnosis of 7 and 10 days and another with domiciliary isolation of 10 days). In10 inpatients the diagnosis delay was 1 to 14 days (mean 4.5). 2. Fifty positive smear patients were followed-up for bacteriology controls. First month control on 14 showed positive smear for all and positive culture for 10 of them. Second month control was performed on 25, 8 of them were smear positive and 7 culture positive. Conclusions: 1. In 13% of patients with TB we did not perform the isolation correctly. 2. There was a high rate of positives smear and culture after one and two months of treatment within TB patients with initial positive smear. We must control isolation policy and bacteriologic response to treatment because of the influence that can have in TB transmission (AU)

Long-term follow-up of Symphony nitinol stents in iliac arteriosclerosis obliterans.

The purpose of this study was to evaluate the long-term results of iliac artery stent placement with use of the symphony stent for the treatment of patients with intermittent claudication. In a prospective study, 31 cases of iliac occlusive arterial disease were treated in 26 patients. Stenoses (n = 27) were treated after failed angioplasty, and occlusions (n = 4) were treated with primary stent placement. Clinical history, clinical stage and the ankle brachial-index (ABI) examination measurement were assessed. The patients were followed up with clinical examination, ABI examination measurement and intravenous angiography. The follow-up period ranged between 9.5 months and 7.5 years (median = 5.9 yr). Data were analyzed using the univariate analysis (Kaplan-Meier method). The mean+/-SD ABI pre-, post-procedure and in the last control was 0.70+/-0.17, 0.97+/-0.15, and 0.96+/-0.20, respectively. Primary patency rates (%) +/- SE were 83+/-7 after 3 years, 75+/-8 after five years, and 67+/-9 after seven years, and secondary patency rates were 93+/-5 after three years, 86+/-7 after five years, and 86+/-7 after seven years. During the first 24 hours, one patient presented occlusion of the treated segment. During follow-up, 9 (29%) patients were admitted to our hospital because of worsening of the symptoms. In this study, the symphony stent has been proven to be a good device to treat lesions in the iliac region but more experience is needed to optimize endovascular treatment in this area. In our experience the treatment of iliac artery occlusive disease with symphony stents can be considered a good option with acceptable patency rates and low morbidity and mortality.

Influence of the tibial stem design on bone density after cemented total knee arthroplasty: a prospective seven-year follow-up study.

We prospectively measured the changes in bone mineral density (BMD) in the proximal tibia of 20 total knee arthroplasties, ten with cruciform stems and ten with cylindrical stems. The measurements were made one, four and seven years after surgery. We observed a uniform density decrease in three regions of interest from one to seven years of follow-up. Cylindrical stems showed an asymmetrical density decrease between the three regions of interest, with no change in the central region, a slight decrease in the lateral region, and large decrease in the medial region. Multivariate analysis with general linear model showed the stem type factor as statistically significant for medial region of interest (p = 0.006). The cylindrical stem produces heterogeneous BMD changes under the tibial platform in knee arthroplasties, and this could be a potential risk factor for asymmetrical subsidence of this component.

Bilateral hypogastric artery occlusion in endovascular repair of abdominal aortic aneurysms and its clinical significance.

PURPOSE: Endovascular treatment of aortoiliac aneurysms near or involving the hypogastric artery (HGA) requires HGA occlusion before endografting to avoid retrograde filling of the aneurysm. The purpose of this study is to evaluate clinical outcomes of bilateral HGA occlusion and determine if benefits gained by endovascular aneurysm repair (EVAR) outweigh the morbidity associated with the procedure. MATERIALS AND METHODS: Between 1999 and 2004, 128 patients with abdominal aortic aneurysm (AAA) were treated with bifurcated endograft placement. Bilateral coverage or embolization of HGAs was performed in 14 patients (10.9%). Embolization was achieved by deployment of coils and coverage was accomplished by extending the endoprosthesis into the external iliac artery. Clinical follow-up and computed tomographic angiography were performed at 1, 3, 6, 9, and 12 months and annually thereafter to detect potential aneurysm growth and endoleaks. RESULTS: During follow-up (range, 1-72 months), buttock claudication was noted in four patients (28.6%), including unilateral claudication in two and bilateral claudication in two. One patient experienced claudication longer than 12 months, which resolved within 18 months. De novo erectile dysfunction was seen in one patient, and pelvic ischemia was not found in any patient. There was no evidence of endoleak, aneurysm enlargement, or death associated with HGA occlusion. CONCLUSIONS: In our series, complications of bilateral HGA occlusion before EVAR were moderate and resolved over time. The benefits gained from EVAR outweigh the clinical problems caused by bilateral HGA occlusion, as there are no technical complications added to the EVAR procedure.

Free-response receiver operating characteristic evaluation of lossy JPEG2000 and object-based set partitioning in hierarchical trees compression of digitized mammograms.

PURPOSE: To assess the effects of two irreversible wavelet-based compression algorithms--Joint Photographic Experts Group (JPEG) 2000 and object-based set partitioning in hierarchical trees (SPIHT)--on the detection of clusters of microcalcifications and masses on digitized mammograms. MATERIALS AND METHODS: The use of the images in this retrospective image-collection study was approved by the institutional review board, and patient informed consent was not required. One hundred twelve mammographic images (28 with one or two clusters of microcalcifications, 19 with one mass, 17 with both abnormal findings, and 48 with normal findings) obtained in 60 women who ranged in age from 25 to 79 years were digitized and compressed at 40:1 and 80:1 by using the JPEG2000 and object-based SPIHT methods. Five experienced radiologists were asked to locate and rate clusters of microcalcifications and masses on the original and compressed images in a free-response receiver operating characteristic (FROC) data acquisition paradigm. Observer performance was evaluated with the jackknife FROC method. RESULTS: The mean FROC figures of merit for detecting clusters of microcalcifications, masses, and both radiographic findings on uncompressed images were 0.80, 0.81, and 0.72, respectively. With object-based SPIHT 80:1 compression, the corresponding values were larger than the values for uncompressed images by 0.005, 0.009, and -0.005, respectively. The 95% confidence interval for the differences in figures of merit between compressed and uncompressed images was -0.039, 0.033 for the microcalcification finding; -0.055, 0.034 for the mass finding; and -0.039, 0.030 for both findings. Because each of these confidence intervals includes zero, no significant difference in detection accuracy between uncompressed and object-based SPIHT 80:1 compression was observed at a P value of 5%. The F test of the null hypothesis that all of the modes (uncompressed and four compressed modes) were equivalent yielded the following results: F = 0.255, P = .903 for the microcalcification finding; F = 0.340, P = .848 for the mass finding; and F = 0.122, P = .975 for both findings. CONCLUSION: To within the accuracy of these measurements, lossy compression of digital mammographic data at 80:1 with JPEG2000 or the object-based SPIHT algorithm can be performed without decreasing the rate of detection of clusters of microcalcifications and masses.

Utilidad del gadolinio como medio de contraste en procedimientos terapéuticos endovasculares / Utility of gadolinium as a contrast medium in endovascular therapeutic procedures

Objetivo: Valorar la utilidad del gadolinio asociado al CO2 como medio de contraste angiográfico para la realización de procedimientos terapéuticos endovasculares en pacientes que presentan alteración de la función renal. Material y métodos: Desde enero del 2000 a junio del 2001 se realizaron 10 tratamientos endovasculares usando CO2 y gadolinio como medio de contraste en pacientes con deterioro de la función renal (creatinina > 1,5 mg/ml).Resultados: La dosis media de gadolinio administrada fue 42 ml. En todos los casos las imágenes diagnósticas o terapéuticas fueron satisfactorias. No se detectaron incrementos significativos entre los valores de urea y creatinina previos y los obtenidos a las 24, 48 y 72 horas después del procedimiento. Conclusión: El gadolinio es un medio de contraste útil en combinación con CO2 para la realización de procedimientos terapéuticos endovasculares en pacientes con deterioro de la función renal (AU)