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1.
Clin Anat ; 2024 May 08.
Article in English | MEDLINE | ID: mdl-38715464

ABSTRACT

The dysplastic hip is characterized by incomplete coverage of the femoral head, resulting in increased risk of early osteoarthritis. The morphological variation of the hip joint is diverse and clear differences exist between females and males. The aim of this observational study was therefore to investigate the relationship between the morphology of the hip, sex, and hip dysplasia using a three-dimensional model. Statistical shape models of the combined femur and pelvic bones were created from bilateral hips of 75 patients. Using manual angle measurements and regression analysis, the characteristic shape differences associated with sex and hip dysplasia were determined. The model showed clear differences associated with sex and hip dysplasia. We found that the acetabular anteversion in females was significantly higher (p < 0.0001) than in males while no significant difference in acetabular anteversion was found between normal and dysplastic hips (p = 0.11). The model showed that decreased acetabular anteversion resulted in the appearance of the cross-over sign and the prominent ischial spine sign commonly associated with retroversion. Sex could be predicted with an area under the curve of 0.99 and hip dysplasia could be predicted with an area under the curve of ≥0.73. Our findings suggest that retroversion is a result of decreased anteversion of the acetabulum and is primarily associated with sex. This finding should be taken into account during the reorientation of the acetabulum in the surgical treatment of hip dysplasia.

2.
Eur Spine J ; 31(2): 248-257, 2022 02.
Article in English | MEDLINE | ID: mdl-34799780

ABSTRACT

PURPOSE: To investigate the spinopelvic alignment and vertebral shape in children, and associations with body composition and structural spinal abnormalities on magnetic resonance imaging (MRI). METHODS: We performed a cross-sectional study embedded in the Generation R Study, a prospective population-based birth cohort. Pelvic incidence and vertebral concavity ratios for each lumbar level were determined on sagittal MRI images in 9-year-old children, and structural spinal abnormalities were scored semi-quantitatively. The BMI-SD score was calculated, and body composition was assessed using DXA scans. Associations of pelvic incidence and vertebral concavity ratios with structural abnormalities and body composition measures were assessed using (multilevel) regression analyses. RESULTS: This study included 522 participants (47.7% boys), aged 9.9 years (IQR 9.7-10.0). The mean pelvic incidence was 36.6° (SD 8.0). Vertebral concavity ratios ranged from 0.87 to 0.90, with significantly lower ratios for boys compared to girls. Associations were found for a larger pelvic incidence with decreased disc height [OR 1.03 (95% CI 1.02-1.05)], and a pelvic incidence in the lowest tertile with less disc bulging [OR 0.73 (95% CI 0.56-0.95)]. Increased vertebral concavity ratio was associated with decreased disc height [OR 14.16 (95% CI 1.28-157.13)]. Finally, increased fat-free mass index was associated with a smaller pelvic incidence [adjusted OR 0.85 (95% CI 0.07-1.63)]. CONCLUSION: The mean pelvic incidence of 9-year-old children is 36.6° on supine MRI images, and a slightly concave shape of the lumbar vertebrae is seen. Spinopelvic alignment is associated with structural spinal abnormalities, and might itself be influenced by the children's body composition.


Subject(s)
Lumbar Vertebrae , Magnetic Resonance Imaging , Body Composition , Child , Cross-Sectional Studies , Female , Humans , Lumbar Vertebrae/diagnostic imaging , Lumbar Vertebrae/pathology , Male , Prospective Studies
3.
Neuro Oncol ; 23(8): 1315-1326, 2021 08 02.
Article in English | MEDLINE | ID: mdl-33560442

ABSTRACT

BACKGROUND: To analyze the effect of treatment on neurocognitive functioning and the association of neurocognition with radiological abnormalities in primary central nervous system lymphoma (PCNSL). METHODS: One hundred and ninety-nine patients from a phase III trial (HOVON 105/ALLG NHL 24), randomized to standard chemotherapy with or without rituximab, followed in patients ≤60 years old by 30-Gy whole-brain radiotherapy (WBRT), were asked to participate in a neuropsychological evaluation before and during treatment, and up to 2 years posttreatment. Scores were transformed into a standardized z-score; clinically relevant changes were defined as a change in z-score of ≥1 SD. The effect of WBRT was analyzed in irradiated patients. All MRIs were centrally assessed for white matter abnormalities and cerebral atrophy, and their relation with neurocognitive scores over time in each domain was calculated. RESULTS: 125/199 patients consented to neurocognitive evaluation. Statistically significant improvements in neurocognition were seen in all domains. A clinically relevant improvement was seen only in the motor speed domain, without differences between the arms. In the follow-up of irradiated patients (n = 43), no change was observed in any domain score, compared to after WBRT. Small but significant inverse correlations were found between neurocognitive scores over time and changes in white matter abnormalities (regression coefficients: -0.048 to -0.347) and cerebral atrophy (-0.212 to -1.774). CONCLUSIONS: Addition of rituximab to standard treatment in PCNSL patients did not impact neurocognitive functioning up to 2 years posttreatment, nor did treatment with 30-Gy WBRT in patients ≤60 years old. Increased white matter abnormalities and brain atrophy showed weak associations with neurocognition.


Subject(s)
Central Nervous System Neoplasms , Lymphoma, Non-Hodgkin , Lymphoma , Humans , Lymphoma, Non-Hodgkin/complications , Lymphoma, Non-Hodgkin/drug therapy , Middle Aged , Neuropsychological Tests , Rituximab/therapeutic use
4.
Int J Cardiovasc Imaging ; 35(11): 2123-2133, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31312998

ABSTRACT

Chronic silent brain infarctions, detected as new white matter hyperintensities on magnetic resonance imaging (MRI) following transcatheter aortic valve implantation (TAVI), are associated with long-term cognitive deterioration. This is the first study to investigate to which extent the calcification volume of the native aortic valve (AV) measured with cardiac computed tomography angiography (CTA) predicts the increase in chronic white matter hyperintensity volume after TAVI. A total of 36 patients (79 ± 5 years, median EuroSCORE II 1.9%, Q1-Q3 1.5-3.4%) with severe AV stenosis underwent fluid attenuation inversion recovery (FLAIR) MRI < 24 h prior to TAVI and at 3 months follow-up for assessment of cerebral white matter hyperintensity volume (mL). Calcification volumes (mm3) of the AV, aortic arch, landing zone and left ventricle were measured on the CTA pre-TAVI. The largest calcification volumes were found in the AV (median 692 mm3) and aortic arch (median 633 mm3), with a large variation between patients (Q1-Q3 482-1297 mm3 and 213-1727 mm3, respectively). The white matter hyperintensity volume increased in 72% of the patients. In these patients the median volume increase was of 1.1 mL (Q1-Q3 0.3-4.6 mL), corresponding with a 27% increase from baseline (Q1-Q3 7-104%). The calcification volume in the AV predicted the increase of white matter hyperintensity volume (Δ%), with a 35% increase of white matter hyperintensity volume, per 100 mm3 of AV calcification volume (SE 8.5, p < 0.001). The calcification volumes in the aortic arch, landing zone and left ventricle were not associated with the increase in white matter hyperintensity volume. In 72% of the patients new chronic white matter hyperintensities developed 3 months after TAVI, with a median increase of 27%. A higher calcification volume in the AV was associated with a larger increase in the white matter hyperintensity volume. These findings show the potential for automated AV calcium screening as an imaging biomarker to predict chronic silent brain infarctions.


Subject(s)
Aortic Valve Stenosis/surgery , Cerebral Infarction/etiology , Leukoencephalopathies/etiology , Transcatheter Aortic Valve Replacement/adverse effects , Aged , Aged, 80 and over , Aortic Valve Stenosis/complications , Aortic Valve Stenosis/diagnostic imaging , Asymptomatic Diseases , Cerebral Infarction/diagnostic imaging , Chronic Disease , Computed Tomography Angiography , Coronary Angiography/methods , Female , Humans , Leukoencephalopathies/diagnostic imaging , Magnetic Resonance Imaging , Male , Prospective Studies , Risk Assessment , Risk Factors , Time Factors , Treatment Outcome
5.
Neurobiol Aging ; 81: 58-66, 2019 09.
Article in English | MEDLINE | ID: mdl-31247459

ABSTRACT

Hippocampal volume and shape are known magnetic resonance imaging biomarkers of neurodegeneration. Recently, hippocampal texture has been shown to improve prediction of dementia in patients with mild cognitive impairment, but it is unknown whether texture adds prognostic information beyond volume and shape and whether the predictive value extends to cognitively healthy individuals. Using 510 subjects from the Rotterdam Study, a prospective, population-based cohort study, we investigated if hippocampal volume, shape, texture, and their combination were predictive of dementia and determined how predictive performance varied with time to diagnosis and presence of early clinical symptoms of dementia. All features showed significant predictive performance with the area under the receiver operating characteristic curve ranging from 0.700 for texture alone to 0.788 for the combination of volume and texture. Although predictive performance extended to those without objective cognitive complaints or mild cognitive impairment, performance decreased with increasing follow-up time. We conclude that a combination of multiple hippocampal features on magnetic resonance imaging performs better in predicting dementia in the general population than any feature by itself.


Subject(s)
Cognitive Dysfunction/pathology , Dementia/pathology , Hippocampus/diagnostic imaging , Hippocampus/pathology , Aged , Aged, 80 and over , Cognitive Dysfunction/diagnostic imaging , Cohort Studies , Dementia/diagnostic imaging , Female , Forecasting , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Organ Size , Prognosis , ROC Curve , Time Factors
6.
IEEE Trans Med Imaging ; 38(1): 213-224, 2019 01.
Article in English | MEDLINE | ID: mdl-30047874

ABSTRACT

Many medical image segmentation methods are based on the supervised classification of voxels. Such methods generally perform well when provided with a training set that is representative of the test images to the segment. However, problems may arise when training and test data follow different distributions, for example, due to differences in scanners, scanning protocols, or patient groups. Under such conditions, weighting training images according to distribution similarity have been shown to greatly improve performance. However, this assumes that a part of the training data is representative of the test data; it does not make unrepresentative data more similar. We, therefore, investigate kernel learning as a way to reduce differences between training and test data and explore the added value of kernel learning for image weighting. We also propose a new image weighting method that minimizes maximum mean discrepancy (MMD) between training and test data, which enables the joint optimization of image weights and kernel. Experiments on brain tissue, white matter lesion, and hippocampus segmentation show that both kernel learning and image weighting, when used separately, greatly improve performance on heterogeneous data. Here, MMD weighting obtains similar performance to previously proposed image weighting methods. Combining image weighting and kernel learning, optimized either individually or jointly, can give a small additional improvement in performance.


Subject(s)
Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Supervised Machine Learning , Algorithms , Hippocampus/diagnostic imaging , Humans , White Matter/diagnostic imaging
7.
Neuroimage Clin ; 20: 466-475, 2018.
Article in English | MEDLINE | ID: mdl-30128285

ABSTRACT

Many successful approaches in MR brain segmentation use supervised voxel classification, which requires manually labeled training images that are representative of the test images to segment. However, the performance of such methods often deteriorates if training and test images are acquired with different scanners or scanning parameters, since this leads to differences in feature representations between training and test data. In this paper we propose a feature-space transformation (FST) to overcome such differences in feature representations. The proposed FST is derived from unlabeled images of a subject that was scanned with both the source and the target scan protocol. After an affine registration, these images give a mapping between source and target voxels in the feature space. This mapping is then used to map all training samples to the feature representation of the test samples. We evaluated the benefit of the proposed FST on hippocampus segmentation. Experiments were performed on two datasets: one with relatively small differences between training and test images and one with large differences. In both cases, the FST significantly improved the performance compared to using only image normalization. Additionally, we showed that our FST can be used to improve the performance of a state-of-the-art patch-based-atlas-fusion technique in case of large differences between scanners.


Subject(s)
Hippocampus/diagnostic imaging , Hippocampus/physiology , Magnetic Resonance Imaging/methods , Transfer, Psychology/physiology , Aged , Databases, Factual , Hippocampus/anatomy & histology , Humans
8.
Fish Shellfish Immunol ; 74: 190-204, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29288813

ABSTRACT

The effects of two protocols (density gradient versus hypotonic lysis) used for leukocyte isolation from three major lymphoid tissue of fish (head-kidney, spleen and blood) were examined on some cell functional activities (tissue leucocytes distributions, phagocytosis, basal and burst oxidative activities) classically used to estimate the fish immune status. Experiments were conducted on roach (Rutilus rutilus), a cyprinid fish model often studied in different eco-physiological contexts (aquaculture, ecotoxicology …). All of immune endpoints were assessed either immediately after cell isolation or after a 12 h of incubation in order to observe if a post-isolation incubation may influence the leukocytes activities. Compared to the density gradient, hypotonic lysis is associated with granulocytes enrichments of cell suspensions. This is particularly true for leukocyte suspensions isolated from head kidney where granulocytes are naturally abundant. However, important variabilities in leukocyte distributions were observed in head kidney and spleen cells samples obtained by the use of hypotonic lysis for two incubation conditions used (no incubation or 12 h of incubation at 4 °C). The density gradient protocol leads to a transitory increase in basal ROS production in spleen lymphocytes and macrophages The blood leukocytes isolated by this same method exhibit high basal oxidative activities after 12 h of incubation at 4 °C and for the three leukocyte types (lymphocytes, monocytes and granulocytes). The hypotonic lysis is associated with an increase in PMA-induced ROS production especially in head kidney leukocytes. The increases in cell oxidative activities are consistent with increases in granulocyte proportions observed in leukocyte suspensions obtained by hypotonic lysis. Finally, the two protocols have no effect on leukocyte mortality and phagocytic activity. Within limits of our experimental conditions, the spleen is the organ whose leukocyte oxidative activities (stimulated or not) are only slightly influenced by the methods used for leukocyte isolation. This is also the case for the anterior kidney, but for this tissue, it is necessary to incubate the isolated cells for 12 h at 4 °C before functional analyses. Each of the two methodologies used has advantages and disadvantages. The hypotonic lysis allows to isolate a greater variety of leukocytes types whereas the density gradient used ensures a better stability of cells distributions over time. However, for the same fish species and for the same tissue, the method used to isolate leukocytes influences results and must be taken into consideration during acquired data analysis for evaluation of fish immune status.


Subject(s)
Cell Separation/veterinary , Cyprinidae/immunology , Immunity, Innate , Leukocytes/cytology , Lymphoid Tissue/cytology , Monitoring, Immunologic/veterinary , Animals , Blood/immunology , Cell Separation/methods , Centrifugation, Density Gradient/methods , Centrifugation, Density Gradient/veterinary , Head Kidney/cytology , Hemolysis , Monitoring, Immunologic/methods , Spleen/cytology
9.
Hum Brain Mapp ; 35(9): 4916-31, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24700485

ABSTRACT

Because hypoperfusion of brain tissue precedes atrophy in dementia, the detection of dementia may be advanced by the use of perfusion information. Such information can be obtained noninvasively with arterial spin labeling (ASL), a relatively new MR technique quantifying cerebral blood flow (CBF). Using ASL and structural MRI, we evaluated diagnostic classification in 32 prospectively included presenile early stage dementia patients and 32 healthy controls. Patients were suspected of Alzheimer's disease (AD) or frontotemporal dementia. Classification was based on CBF as perfusion marker, gray matter (GM) volume as atrophy marker, and their combination. These markers were each examined using six feature extraction methods: a voxel-wise method and a region of interest (ROI)-wise approach using five ROI-sets in the GM. These ROI-sets ranged in number from 72 brain regions to a single ROI for the entire supratentorial brain. Classification was performed with a linear support vector machine classifier. For validation of the classification method on the basis of GM features, a reference dataset from the AD Neuroimaging Initiative database was used consisting of AD patients and healthy controls. In our early stage dementia population, the voxelwise feature-extraction approach achieved more accurate results (area under the curve (AUC) range = 86 - 91%) than all other approaches (AUC = 57 - 84%). Used in isolation, CBF quantified with ASL was a good diagnostic marker for dementia. However, our findings indicated only little added diagnostic value when combining ASL with the structural MRI data (AUC = 91%), which did not significantly improve over accuracy of structural MRI atrophy marker by itself.


Subject(s)
Alzheimer Disease/diagnosis , Brain/pathology , Brain/physiopathology , Cerebrovascular Circulation , Image Interpretation, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Aged , Alzheimer Disease/pathology , Alzheimer Disease/physiopathology , Area Under Curve , Atrophy , Diagnosis, Differential , Female , Frontotemporal Dementia/diagnosis , Frontotemporal Dementia/pathology , Frontotemporal Dementia/physiopathology , Gray Matter/pathology , Humans , Linear Models , Male , Middle Aged , Organ Size , Prospective Studies , Support Vector Machine
10.
Hum Brain Mapp ; 35(5): 2359-71, 2014 May.
Article in English | MEDLINE | ID: mdl-24039001

ABSTRACT

Previous studies have shown that hippocampal volume is an early marker for dementia. We investigated whether hippocampal shape characteristics extracted from MRI scans are predictive for the development of dementia during follow up in subjects who were nondemented at baseline. Furthermore, we assessed whether hippocampal shape provides additional predictive value independent of hippocampal volume. Five hundred eleven brain MRI scans from elderly nondemented participants of a prospective population-based imaging study were used. During the 10-year follow-up period, 52 of these subjects developed dementia. For training and evaluation independent of age and gender, a subset of 50 cases and 150 matched controls was selected. The hippocampus was segmented using an automated method. From the segmentation, the volume was determined and a statistical shape model was constructed. We trained a classifier to distinguish between subjects who developed dementia and subjects who stayed cognitively healthy. For all subjects the a posteriori probability to develop dementia was estimated using the classifier in a cross-validation experiment. The area under the ROC curve for volume, shape, and the combination of both were, respectively, 0.724, 0.743, and 0.766. A logistic regression model showed that adding shape to a model using volume corrected for age and gender increased the global model-fit significantly (P = 0.0063). We conclude that hippocampal shape derived from MRI scans is predictive for dementia before clinical symptoms arise, independent of age and gender. Furthermore, the results suggest that hippocampal shape provides additional predictive value over hippocampal volume and that combining shape and volume leads to better prediction.


Subject(s)
Aging/pathology , Dementia/diagnosis , Hippocampus/pathology , Aged , Aged, 80 and over , Brain Mapping , Cohort Studies , Female , Follow-Up Studies , Humans , Image Processing, Computer-Assisted , Logistic Models , Magnetic Resonance Imaging , Male , Middle Aged , Neuropsychological Tests , ROC Curve
11.
Ann Vasc Surg ; 25(4): 481-4, 2011 May.
Article in English | MEDLINE | ID: mdl-21549916

ABSTRACT

BACKGROUND: Allogeneic blood products have become a limited and expensive resource. The Continuous Autotransfusion System (CATS) has been promoted as a method for reducing the need for allogeneic blood transfusion. This study was undertaken to ascertain whether the use of CATS in emergency open AAA surgery has any benefits. METHODS: This is a retrospective study of all patients undergoing emergency open AAA surgery in our center during a 5-year period (between July 2004 and July 2009). Patients were identified from a prospectively maintained vascular database, and data were obtained from patient records. RESULTS: CATS was used in 69 emergency open AAA repairs. The median total blood loss was 3,500 mL (range: 751-13,796 mL) but the median volume of packed red blood cells produced by CATS was only 493 mL (~ 2 U). An average of 7 U (range: 0-19 U) of bank blood was still used despite the availability of CATS. The mean hemoglobin 24 hours postoperatively was 10.3 g/dL (6.4-14.1) with a hematocrit of 0.30. CONCLUSION: The use of CATS in emergency AAA surgery does not seem to reduce the use of allogeneic blood transfusion. This may be because of over transfusion, as reflected by relatively high postoperative hemoglobin levels.


Subject(s)
Aortic Aneurysm, Abdominal/surgery , Aortic Rupture/surgery , Blood Loss, Surgical/prevention & control , Blood Transfusion, Autologous/instrumentation , Operative Blood Salvage/instrumentation , Vascular Surgical Procedures , Aged , Aortic Aneurysm, Abdominal/blood , Aortic Rupture/blood , Biomarkers/blood , Blood Component Transfusion , Blood Transfusion, Autologous/adverse effects , England , Equipment Design , Female , Hematocrit , Hemoglobins/metabolism , Humans , Male , Operative Blood Salvage/adverse effects , Retrospective Studies , Time Factors , Treatment Outcome , Vascular Surgical Procedures/adverse effects
12.
Medicina (B.Aires) ; 65(6): 533-540, 2005. tab
Article in Spanish | BINACIS | ID: bin-123335

ABSTRACT

Durante el embarazo y la lactancia la mujer debe formar y mantener el esqueleto del feto y del neonato, lo que demanda importantes adaptaciones hormonales y metabólicas. La absorción intestinal de calcio aumenta desde el inicio del embarazo siendo máxima en los últimos trimestres. Se produceuna hipercalciuria que desaparece al suspender la lactancia. El calcio de la leche proviene de la reducción ensu excreción urinaria y de un aumento de la resorción ósea. Las oncentraciones de 1,25 (OH)(2) D(3) se duplican desde el comienzo del embarazo manteniéndose elevadas hasta el parto, debido a un aumento de la actividad de la 1-alfa-hidroxilasa placentaria, normalizándose durante la lactancia. Los estrógenos, prolactina y lactógeno placentario, hormonas implicadas en el aumento de la absorción intestinal de calcio, aumentan conjuntamente.La parathormona (PTH) se mantiene en rango normal o bajo, por lo tanto sus acciones fisiológicas serían ejercidas por el péptido relacionado con la PTH (PTHrP), cuyos niveles aumentan tardíamente en el embarazo y permanecen elevados durante el parto y la lactancia. La calcitonina se eleva durante el embarazo, cae durante la lactancia, y se normaliza al finalizar la misma. El papel fisiológico del factor de necrosis tumoral, interleuquina 1, interleuquina 6 y osteoprotegerina todavía no han sido aclarados. Los cambios analizados favorecen,en casos excepcionales, el desarrollo de osteoporosis generalizada y regional. El objetivo de este trabajo es revisar la bibliografía publicada sobre la fisiopatología y clínica de estas entidades.(AU)


During pregnancy and lactation women have to form and maintain fetus and newborn skeleton. These processes require maternal hormonal and metabolic adjustments. During the first weeks of pregnancy, calcium intestinal absorption rise and reach a maximum in the last trimester. Hypercalciuria can be detected until lactation is stopped. During lactation, calcium that is present in maternal milk, results from lowering maternal calcium excretion and increasing bone resorption. Plasma 1,25 (OH)(2) D(3) levels increase two-fold early in pregnancy due to high placental 1-alpha-hydroxilase activity, remain high until delivery and decline to normal values during lactation. Estrogen, prolactin and placental lactogen, which are involved in calcium absorption, increase at the same time. Normal or even low levels of parathyroid hormone (PTH) can be detected during pregnancy. This suggests that their physiological actions could be mimicked by the parathyroid- related-peptide (PTHrP), which increases in late stages of pregnancy and remain high during delivery and lactation. Calcitonin levels increase during pregnancy, decline during lactation and return to normal values after lactation is stopped. The physiological roll of tumor necrosis factor, interleukin 6 and osteoprotegerin has not been elucidated yet. The above mentioned changes can exceptionally lead to generalized or regional osteoporosis. The aim of this article is to review the published bibliography concerning the physiopathology of these diseases.(AU)


Subject(s)
Humans , Female , Pregnancy , Adult , Lactation/metabolism , Osteoporosis/metabolism , Pregnancy Complications/metabolism , Bone Density/physiology , Bone Resorption/etiology , Bone Resorption/metabolism , Calcium/metabolism , Calcium/therapeutic use , Absorptiometry, Photon , Glomerular Filtration Rate/physiology , Intestinal Absorption/physiology , Lactation/physiology , Osteoporosis/physiopathology , Osteoporosis/diagnostic imaging , Parathyroid Hormone/metabolism , Phosphorus/metabolism , Pregnancy Complications/physiopathology , Pregnancy Complications/diagnostic imaging , Vitamin D/metabolism , Vitamin D/therapeutic use
13.
Medicina (B.Aires) ; 65(6): 489-494, 2005. tab, graf
Article in Spanish | BINACIS | ID: bin-123325

ABSTRACT

Tanto la osteoporosis generalizada como la regional son enfermedades que excepcionalmente seasocian con el embarazo. El objetivo de este trabajo es revisar nuestra experiencia en el diagnósticoy tratamiento de estas afecciones. Entre 1984 y 2004 consultaron seis puérperas por osteoporosis y dospor osteoporosis regional. En el primer grupo tres pacientes refirieron fracturas vertebrales y las restantes gravedesmineralización detectada por densitometría ósea (DEXA). Los síntomas comenzaron en el tercer trimestre o en el posparto inmediato. Cinco eran primíparas mientras que una era multípara y había amamantado porun tiempo prolongado. Los factores de riesgo detectados fueron: baja ingesta láctea, delgadez, osteoporosisfamiliar, amenorreas, tabaquismo y corticoterapia. El laboratorio mostró recambio óseo acelerado. La DEXAdocumentó marcada desmineralización especialmente en esqueleto axial. En todas se interrumpió la lactanciay se indicaron drogas anti-resortivas en cuatro, estrógenos en una y sólo calcio y vitamina D en otra. Todas, menos una, evolucionaron favorablemente independientemente del tratamiento utilizado. Dos pacientes consultaronpor dolor y limitación funcional progresiva durante el embarazo, en cadera izquierda y pie derecho respectivamente. La DEXA mostró desmineralización del lado afectado. El diagnóstico de osteoporosis regionalse confirmó por resonancia magnética nuclear. Los informes de laboratorio indicaron aumento del turnover óseo.Ambas fueron tratadas exitosamente con reposo y bifosfonatos.(AU)


Both generalized and regional osteoporosis exceptionally occur during pregnancy and lactation. The aim of this paper is to show our experience in the diagnosis and treatment of these diseases. From 1984 to 2004 six lactating women with osteoporosis and two with regional osteoporosis consulted us. In the former group, three patients had vertebral fractures and the others experienced substantial demineralization detected by dual-energy X-ray absorptiometry (DXA). In all cases, symptoms began during the third trimester of pregnancy or immediately after delivery. Five of them were primiparous and one was multiparous with a long period of lactation. Risk factors were: low calcium intake, low weight, family history of osteoporosis, amenorrhea, cigarette consumption and corticosteroid therapy. Laboratory tests evidenced increased bone turnover. DXA scan showed substantial demineralization, particularly in axial skeleton. Lactation was interrupted in all women and four received anti-resorptive drugs, one estrogen and only calcium plus vitamin D the remaining. All of them, but one, evolved successfully. The women affected by regional osteoporosis complained of unilateral pain and progressive functional limitation of right foot and left hip respectively. Reduced bone mineral density at symptomatic sites was seen by DXA. Diagnosis was confirmed by typical magnetic resonance imaging pattern. Both patients cured with rest and bisphosfonates treatment.(AU)


Subject(s)
Humans , Pregnancy , Adult , Humans , Female , Lactation/physiology , Osteoporosis/physiopathology , Pregnancy Complications/physiopathology , Bone Density/physiology , Breast Feeding/adverse effects , Calcium/analysis , Calcium/therapeutic use , Absorptiometry, Photon , Femur Neck , Follow-Up Studies , Osteoporosis/drug therapy , Pregnancy Complications/drug therapy , Spine , Vitamin D/therapeutic use , Vitamin D Deficiency/drug therapy
14.
Medicina (B.Aires) ; 65(6): 533-540, 2005. tab
Article in Spanish | LILACS | ID: lil-443092

ABSTRACT

Durante el embarazo y la lactancia la mujer debe formar y mantener el esqueleto del feto y del neonato, lo que demanda importantes adaptaciones hormonales y metabólicas. La absorción intestinal de calcio aumenta desde el inicio del embarazo siendo máxima en los últimos trimestres. Se produceuna hipercalciuria que desaparece al suspender la lactancia. El calcio de la leche proviene de la reducción ensu excreción urinaria y de un aumento de la resorción ósea. Las oncentraciones de 1,25 (OH)(2) D(3) se duplican desde el comienzo del embarazo manteniéndose elevadas hasta el parto, debido a un aumento de la actividad de la 1-alfa-hidroxilasa placentaria, normalizándose durante la lactancia. Los estrógenos, prolactina y lactógeno placentario, hormonas implicadas en el aumento de la absorción intestinal de calcio, aumentan conjuntamente.La parathormona (PTH) se mantiene en rango normal o bajo, por lo tanto sus acciones fisiológicas serían ejercidas por el péptido relacionado con la PTH (PTHrP), cuyos niveles aumentan tardíamente en el embarazo y permanecen elevados durante el parto y la lactancia. La calcitonina se eleva durante el embarazo, cae durante la lactancia, y se normaliza al finalizar la misma. El papel fisiológico del factor de necrosis tumoral, interleuquina 1, interleuquina 6 y osteoprotegerina todavía no han sido aclarados. Los cambios analizados favorecen,en casos excepcionales, el desarrollo de osteoporosis generalizada y regional. El objetivo de este trabajo es revisar la bibliografía publicada sobre la fisiopatología y clínica de estas entidades.


During pregnancy and lactation women have to form and maintain fetus and newborn skeleton. These processes require maternal hormonal and metabolic adjustments. During the first weeks of pregnancy, calcium intestinal absorption rise and reach a maximum in the last trimester. Hypercalciuria can be detected until lactation is stopped. During lactation, calcium that is present in maternal milk, results from lowering maternal calcium excretion and increasing bone resorption. Plasma 1,25 (OH)(2) D(3) levels increase two-fold early in pregnancy due to high placental 1-alpha-hydroxilase activity, remain high until delivery and decline to normal values during lactation. Estrogen, prolactin and placental lactogen, which are involved in calcium absorption, increase at the same time. Normal or even low levels of parathyroid hormone (PTH) can be detected during pregnancy. This suggests that their physiological actions could be mimicked by the parathyroid- related-peptide (PTHrP), which increases in late stages of pregnancy and remain high during delivery and lactation. Calcitonin levels increase during pregnancy, decline during lactation and return to normal values after lactation is stopped. The physiological roll of tumor necrosis factor, interleukin 6 and osteoprotegerin has not been elucidated yet. The above mentioned changes can exceptionally lead to generalized or regional osteoporosis. The aim of this article is to review the published bibliography concerning the physiopathology of these diseases.


Subject(s)
Humans , Female , Pregnancy , Adult , Pregnancy Complications/metabolism , Lactation/metabolism , Osteoporosis/metabolism , Absorptiometry, Photon , Intestinal Absorption/physiology , Calcium/metabolism , Calcium/therapeutic use , Pregnancy Complications/physiopathology , Pregnancy Complications , Bone Density/physiology , Phosphorus/metabolism , Parathyroid Hormone/metabolism , Lactation/physiology , Osteoporosis/physiopathology , Osteoporosis , Bone Resorption/etiology , Bone Resorption/metabolism , Glomerular Filtration Rate/physiology , Vitamin D/metabolism , Vitamin D/therapeutic use
15.
Medicina (B.Aires) ; 65(6): 489-494, 2005. tab, graf
Article in Spanish | LILACS | ID: lil-443102

ABSTRACT

Tanto la osteoporosis generalizada como la regional son enfermedades que excepcionalmente seasocian con el embarazo. El objetivo de este trabajo es revisar nuestra experiencia en el diagnósticoy tratamiento de estas afecciones. Entre 1984 y 2004 consultaron seis puérperas por osteoporosis y dospor osteoporosis regional. En el primer grupo tres pacientes refirieron fracturas vertebrales y las restantes gravedesmineralización detectada por densitometría ósea (DEXA). Los síntomas comenzaron en el tercer trimestre o en el posparto inmediato. Cinco eran primíparas mientras que una era multípara y había amamantado porun tiempo prolongado. Los factores de riesgo detectados fueron: baja ingesta láctea, delgadez, osteoporosisfamiliar, amenorreas, tabaquismo y corticoterapia. El laboratorio mostró recambio óseo acelerado. La DEXAdocumentó marcada desmineralización especialmente en esqueleto axial. En todas se interrumpió la lactanciay se indicaron drogas anti-resortivas en cuatro, estrógenos en una y sólo calcio y vitamina D en otra. Todas, menos una, evolucionaron favorablemente independientemente del tratamiento utilizado. Dos pacientes consultaronpor dolor y limitación funcional progresiva durante el embarazo, en cadera izquierda y pie derecho respectivamente. La DEXA mostró desmineralización del lado afectado. El diagnóstico de osteoporosis regionalse confirmó por resonancia magnética nuclear. Los informes de laboratorio indicaron aumento del turnover óseo.Ambas fueron tratadas exitosamente con reposo y bifosfonatos.


Both generalized and regional osteoporosis exceptionally occur during pregnancy and lactation. The aim of this paper is to show our experience in the diagnosis and treatment of these diseases. From 1984 to 2004 six lactating women with osteoporosis and two with regional osteoporosis consulted us. In the former group, three patients had vertebral fractures and the others experienced substantial demineralization detected by dual-energy X-ray absorptiometry (DXA). In all cases, symptoms began during the third trimester of pregnancy or immediately after delivery. Five of them were primiparous and one was multiparous with a long period of lactation. Risk factors were: low calcium intake, low weight, family history of osteoporosis, amenorrhea, cigarette consumption and corticosteroid therapy. Laboratory tests evidenced increased bone turnover. DXA scan showed substantial demineralization, particularly in axial skeleton. Lactation was interrupted in all women and four received anti-resorptive drugs, one estrogen and only calcium plus vitamin D the remaining. All of them, but one, evolved successfully. The women affected by regional osteoporosis complained of unilateral pain and progressive functional limitation of right foot and left hip respectively. Reduced bone mineral density at symptomatic sites was seen by DXA. Diagnosis was confirmed by typical magnetic resonance imaging pattern. Both patients cured with rest and bisphosfonates treatment.


Subject(s)
Humans , Pregnancy , Adult , Female , Pregnancy Complications/physiopathology , Lactation/physiology , Osteoporosis/physiopathology , Absorptiometry, Photon , Breast Feeding/adverse effects , Calcium/analysis , Calcium/therapeutic use , Pregnancy Complications/drug therapy , Vitamin D Deficiency/drug therapy , Bone Density/physiology , Femur Neck , Follow-Up Studies , Osteoporosis/drug therapy , Spine , Vitamin D/therapeutic use
16.
Radiology ; 221(3): 633-40, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11719657

ABSTRACT

PURPOSE: To assess the performance of radiologists in the detection of masses and microcalcification clusters on digitized mammograms by using different computer-assisted detection (CAD) cuing environments. MATERIALS AND METHODS: Two hundred nine digitized mammograms depicting 57 verified masses and 38 microcalcification clusters in 85 positive and 35 negative cases were interpreted independently by seven radiologists using five display modes. Except for the first mode, for which no CAD results were provided, suspicious regions identified with a CAD scheme were cued in all the other modes by using a combination of two cuing sensitivities (90% and 50%) and two false-positive rates (0.5 and 2.0 per image). A receiver operating characteristic study was performed by using soft-copy images. RESULTS: CAD cuing at 90% sensitivity and a rate of 0.5 false-positive region per image improved observer performance levels significantly (P < .01). As accuracy of CAD cuing decreased so did observer performances (P < .01). Cuing specificity affected mass detection more significantly, while cuing sensitivity affected detection of microcalcification clusters more significantly (P < .01). Reduction of cuing sensitivity and specificity significantly increased false-negative rates in noncued areas (P < .05). Trends were consistent for all observers. CONCLUSION: CAD systems have the potential to significantly improve diagnostic performance in mammography. However, poorly performing schemes could adversely affect observer performance in both cued and noncued areas.


Subject(s)
Breast Neoplasms/diagnostic imaging , Mammography , Radiographic Image Interpretation, Computer-Assisted , Area Under Curve , Calcinosis/diagnostic imaging , Cues , False Positive Reactions , Female , Humans , Observer Variation , ROC Curve , Sensitivity and Specificity
17.
Neurosurg Clin N Am ; 12(4): 761-73, ix, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11524297

ABSTRACT

This article presents a brief history of normal-pressure hydrocephalus, its clinical presentation, and different theories on its pathophysiology. The different diagnostic tests, differential diagnosis, and its treatment are presented.


Subject(s)
Hydrocephalus, Normal Pressure/diagnosis , Brain/physiopathology , Cerebral Ventricles/physiopathology , Cerebrospinal Fluid Pressure/physiology , Diagnostic Imaging , Humans , Hydrocephalus, Normal Pressure/pathology , Hydrocephalus, Normal Pressure/physiopathology , Neurologic Examination , Prognosis , Ventriculoperitoneal Shunt
18.
Med Phys ; 28(4): 455-61, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11339741

ABSTRACT

The purpose of this work was to develop and evaluate a computer-aided detection (CAD) scheme for the improvement of mass identification on digitized mammograms using a knowledge-based approach. Three hundred pathologically verified masses and 300 negative, but suspicious, regions, as initially identified by a rule-based CAD scheme, were randomly selected from a large clinical database for development purposes. In addition, 500 different positive and 500 negative regions were used to test the scheme. This suspicious region pruning scheme includes a learning process to establish a knowledge base that is then used to determine whether a previously identified suspicious region is likely to depict a true mass. This is accomplished by quantitatively characterizing the set of known masses, measuring "similarity" between a suspicious region and a "known" mass, then deriving a composite "likelihood" measure based on all "known" masses to determine the state of the suspicious region. To assess the performance of this method, receiver-operating characteristic (ROC) analyses were employed. Using a leave-one-out validation method with the development set of 600 regions, the knowledge-based CAD scheme achieved an area under the ROC curve of 0.83. Fifty-one percent of the previously identified false-positive regions were eliminated, while maintaining 90% sensitivity. During testing of the 1,000 independent regions, an area under the ROC curve as high as 0.80 was achieved. Knowledge-based approaches can yield a significant reduction in false-positive detections while maintaining reasonable sensitivity. This approach has the potential of improving the performance of other rule-based CAD schemes.


Subject(s)
Mammography/methods , Software , Breast Neoplasms/diagnosis , Databases, Factual , Female , Humans , Mammography/instrumentation , Models, Statistical , ROC Curve
19.
AJR Am J Roentgenol ; 176(3): 603-6, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11222188

ABSTRACT

OBJECTIVE: This study evaluated helical CT as an imaging modality for preoperative staging of endometrial carcinoma. MATERIALS AND METHODS: Three radiologists retrospectively and independently reviewed the preoperative helical CT scans of 25 consecutive patients with endometrial carcinoma. The presence or absence of deep myometrial invasion and the presence or absence of cervical involvement were evaluated on helical CT and compared with pathologic findings at hysterectomy. RESULTS: Helical CT has a sensitivity of 83% and a specificity of 42% for the detection of deep myometrial invasion (stage IC). Helical CT has a sensitivity of 25% and a specificity of 70% for the detection of cervical involvement (state II). These results compare poorly with those of MR imaging (sensitivity 92%, specificity 90% for the detection of deep myometrial invasion; sensitivity 86%, specificity 97% for the detection of cervical involvement). CONCLUSION: Helical CT is insensitive and nonspecific compared with MR imaging for the preoperative staging of endometrial carcinoma. MR imaging remains the imaging modality of choice.


Subject(s)
Carcinoma, Endometrioid/diagnostic imaging , Endometrial Neoplasms/diagnostic imaging , Tomography, X-Ray Computed/methods , Aged , Carcinoma, Endometrioid/pathology , Carcinoma, Endometrioid/surgery , Endometrial Neoplasms/pathology , Endometrial Neoplasms/surgery , Endometrium/pathology , Female , Humans , Magnetic Resonance Imaging , Neoplasm Invasiveness , Neoplasm Staging , Preoperative Care , Sensitivity and Specificity
20.
Oncogene ; 18(47): 6488-95, 1999 Nov 11.
Article in English | MEDLINE | ID: mdl-10597251

ABSTRACT

Hematopoietic cell growth, differentiation, and commitment to a restricted lineage are guided by a set of cytokines acting exclusively on cells expressing the corresponding cytokine receptor. The macrophage colony stimulating factor (M-CSF, also termed CSF-1) and its cognate receptor, the tyrosine kinase c-Fms, are essential for monocyte and macrophage development. The underlying molecular mechanism, however, is poorly understood. Here we identified a novel Fms-interacting protein (FMIP, MW 78 kDa) which binds transiently via its N-terminal 144 residues to the cytoplasmic domain of activated Fms-molecules. Binding of FMIP was paralleled by rapid tyrosine phosphorylation within the binding domain which drastically reduced its ability to associate with Fms. Binding was specific as evidenced by co-immunoprecipitation and association with recombinant GST-Fms fusion proteins. No binding was observed with the tyrosine phosphorylated cytoplasmic domains of c-Kit, TrkA, c-Met, and the insulin receptor. The role of FMIP in hematopoietic differentiation was studied in the bipotential myeloid progenitor cell line, FDC-P1Mac11. Overexpression of FMIP prevented M-CSF induced macrophage differentiation. Instead, cells differentiated into granulocytes. Our data suggest that the level of FMIP expression could form a threshold that decides about differentiation either into macrophages or into granulocytes.


Subject(s)
Carrier Proteins/metabolism , Cell Differentiation , Granulocytes/cytology , Intracellular Signaling Peptides and Proteins , Macrophages/cytology , Amino Acid Sequence , Carrier Proteins/chemistry , Carrier Proteins/genetics , Cell Line , Macrophage Colony-Stimulating Factor/physiology , Molecular Sequence Data , Phosphorylation , Protein Binding , Receptor Protein-Tyrosine Kinases/metabolism , Receptor, Macrophage Colony-Stimulating Factor/metabolism , Substrate Specificity
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