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1.
Magn Reson Imaging ; 98: 149-154, 2023 05.
Article in English | MEDLINE | ID: mdl-36681313

ABSTRACT

PURPOSE: To evaluate the intraindividual reproducibility of functional lung imaging using non-contrast enhanced multi breath-hold 3D-UTE MRI. METHODS: Ten healthy volunteers underwent non-contrast enhanced 3D-UTE MRI at three time points for same-day and different-day measurements employing a stack-of-spirals trajectory at 3 T. At each time point, inspiratory and expiratory breathing states were acquired for tidal and deep breathing, each within a single breath-hold. For functional image analysis, fractional ventilation (FV) was calculated pixelwise after image registration from the MR signal change. To decouple FV from breathing depth, the individual lung volume was used for volume adjustment (rFV). Reproducibility evaluation was performed in eight lung segments. Statistical analyses included two way mixed intraclass correlation (ICC), sign-test, Friedman-test and modified Bland-Altman analyses. RESULTS: FV from tidal breathing showed an ICC of 0.81, a bias of 1.3% and an interval of confidence (CI) ranging from -67.1 to 69.6%. FV from deep breathing was higher reproducible with an ICC of 0.92 (bias, -0.2%; CI, -34.2 to 33.7%). Following volume adjustment, reproducibility of rFV for tidal breathing improved (ICC, 0,86; bias, 2.0%; CI, -34.3 to 38.3%), whereas it did not bear significant benefits for deep breathing (ICC, 0.89; bias, 2.8%; CI, -24.9 to 30.5%). Reproducibility was independent from the examination day. CONCLUSION: Non-contrast-enhanced multi breath-hold 3D-UTE MRI allows for highly reproducible ventilation imaging.


Subject(s)
Imaging, Three-Dimensional , Magnetic Resonance Imaging , Humans , Reproducibility of Results , Magnetic Resonance Imaging/methods , Imaging, Three-Dimensional/methods , Lung/diagnostic imaging , Breath Holding
2.
Lymphology ; 53(4): 195-203, 2020.
Article in English | MEDLINE | ID: mdl-33721925

ABSTRACT

Resistance exercise is deemed safe for women recovering from conventional breast cancer therapies but few clinicians are aware that dragon boat racing, as a form of resistive exercise, is available to the breast cancer community. The objectives of this study were to 1) increase clinician awareness of dragon boat racing (DBR) in breast cancer survivors as a community-based physical activity, and 2) evaluate quality of life (QOL) in breast cancer survivors with or without lymphedema who participate in DBR. This prospective, observational study surveyed 1,069 international breast cancer dragon boat racers from eight countries to compare function, activity, and participation in women with and without selfreported lymphedema using the Lymph-ICF questionnaire. Seventy-one percent of women (n=758) completed the questionnaires. Results revealed significantly higher Lymph-ICF scores in the lymphedema participants, signifying reduced QOL, when compared to the nonlymphedema participants (p<0.05), except for "go on vacation" for which no statistical difference was reported (p=0.20). International breast cancer survivors with lymphedema participating in DBR at an international competition had reduced function, limited activity, and restricted participation compared to participants without lymphedema. Clinicians should consider utilizing DBR as a community-based activity to support exercise and physical activity after a breast cancer diagnosis.


Subject(s)
Breast Neoplasms , Cancer Survivors , Lymphedema , Breast Neoplasms/therapy , Female , Humans , Lymphedema/etiology , Prospective Studies , Quality of Life
3.
Eur J Dent Educ ; 21(3): 200-205, 2017 Aug.
Article in English | MEDLINE | ID: mdl-26960967

ABSTRACT

INTRODUCTION: With increasing use of digital scanning with restorative procedures in the dental office, it becomes necessary that educational institutions adopt instructional methodology for introducing this technology together with conventional impression techniques. OBJECTIVE: To compare the time differences between instructing dental students on digital scanning (DS) (LAVA C.O.S. digital impression system) and a conventional impression technique (CI) (polyvinyl siloxane), and to compare students' attitudes and beliefs towards both techniques. MATERIALS AND METHODS: Volunteer sophomore dental students (n = 25) with no prior experience in clinical impressions were recruited and IRB consent obtained. Participants responded to a pre-and post-exposure questionnaire. Participants were instructed on the use of both DS and CI for a single tooth full coverage crown restoration using a consecutive sequence of video lecture, investigator-led demonstration and independent impression exercise. The time necessary for each step (minutes) was recorded. Statistical significance was calculated using dependent t-tests (time measurements) and 2-sample Mann-Whitney (questionnaire responses). RESULTS: The time spent teaching students was greater for DS than CI for video lecture (15.95 and 10.07 min, P = 0.0000), demonstration time (9.06 and 4.70 min, P = 0.0000) and impression time (18.17 and 8.59 min, P = 0.0000). Prior to the instruction and practice, students considered themselves more familiar with CI (3.96) than DS (1.96) (P = 0.0000). After the instruction and practice, participants reported CI technique proved significantly easier than expected (pre-instruction: 3.52 and post-instruction: 4.08, P = 0.002). However, overall participants' perception of ease of use for DS was not influenced by this instruction and practice experience (pre-instruction: 3.84 and post-instruction: 3.56, P = 0.106). Despite the results, 96% of participants expressed an expectation that DS will become their predominant impression technique during their careers. CONCLUSIONS: Dental students with no clinical experience have high expectations for digital scanning, and despite their initial difficulty, expect it to become their primary impression technique during their professional futures. The instructional time necessary for introducing DS into the curriculum is significantly greater than CI in both classroom (lecture) and clinical simulation settings (investigator-led demonstration).


Subject(s)
Computer-Aided Design , Crowns , Dental Impression Materials , Dental Impression Technique , Education, Dental , Students, Dental , Tooth/diagnostic imaging , Attitude of Health Personnel , Humans , Manikins , Models, Dental , Polyvinyls , Siloxanes , Surveys and Questionnaires , Tooth/anatomy & histology
4.
Ophthalmologe ; 113(12): 1046-1050, 2016 Dec.
Article in German | MEDLINE | ID: mdl-27286673

ABSTRACT

BACKGROUND: Uveal melanomas (UM) are rare malignancies in young patients. It is unknown if UM in young patients significantly differs from those in older patients concerning tumor size and localization, metastasis and genetics. The aim of this study was to evaluate the clinical course and tumor characteristics in young patients with UM. MATERIAL AND METHODS: All patients with UM below the age of 32 years who had been treated at our hospital were included in the study. Patient age and sex, duration of symptoms, visual impairment, tumor size and location, genetics, therapy, follow-up interventions and tumor-associated deaths were documented. RESULTS: A total of 57 patients (67 % male, mean age 24.7 years) were included in the study with an average symptomatic course of 5 months. Of the patients 8 (14 %) had an initial visual acuity of ≥ 0.9, 16 (28 %) 0.5-0.8, 22 (39 %) 0.05-0.4 and 9 (16 %) < 0.05 (no data for 2 patients, 4 %). After therapy visual acuity was < 0.05 in 54 % and 53 % of the tumors were choroidal UM (70 % juxtapapillary/circumpapillary), whereas 47 % were ciliochoroidal (54 % with iridociliary involvement). The average tumor size was 12.7 ± 3.6 mm with an average prominence of 6.2 ± 3.2 mm. Genetic evaluation (n = 16) revealed disomy 3 in 64 % and 54 % of the patients received radiotherapy with local application of ruthenium 106. In 46 % of cases follow-up interventions were neccessary including 70 % due to radiogenic retinopathy. CONCLUSION: In young patients UM did not show any preferred localization. The majority of genetically evaluated tumors revealed disomy 3 with no significant correlation to tumor location. Independent of tumor size, location and therapy, approximately half of the patients needed follow-up interventions, predominantly due to radiogenic retinopathy.


Subject(s)
Melanoma/mortality , Melanoma/radiotherapy , Neoplasm Recurrence, Local/mortality , Neoplasm Recurrence, Local/prevention & control , Uveal Neoplasms/mortality , Uveal Neoplasms/radiotherapy , Adolescent , Adult , Age Distribution , Causality , Ciliary Body/pathology , Comorbidity , Disease Progression , Female , Germany/epidemiology , Humans , Iris Neoplasms/mortality , Iris Neoplasms/radiotherapy , Male , Prognosis , Retrospective Studies , Sex Distribution , Survival Rate , Tumor Burden , Vision Disorders , Young Adult
5.
Placenta ; 39: 87-93, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26992680

ABSTRACT

OBJECTIVE: Maternal magnesium (Mg) deficiency has been associated with fetal growth restriction. Using a mouse model of maternal Mg deficiency-induced fetal growth restriction, we sought to investigate the effect of Mg deficiency on placental physiology and function. METHODS: In vivo: Pregnant Swiss Webster mice were fed either 100% of the recommended amount of Mg (control) or 10%Mg (Mg-deficient) (8 per group). Dams were euthanized on gestational day 17 and placentas were collected, weighed and assessed for Mg concentrations, as well as nutrient transporter mRNA expression. For nutrient transfer studies, control and Mg-deficient dams (6 per group) were injected with (14)C-amino acids and (3)H-glucose and trans-placental passage was determined. In vitro: BeWo placental cells were grown in media containing 10%Mg to 100%Mg and the effects of Mg status on cell proliferation, oxidative stress and nutrient uptake were measured. Data were analyzed by Student's t-tests comparing controls vs. Mg-deficient animals or cells. For multiple comparisons, data were analyzed by ANOVA followed by Dunnett's post hoc testing. RESULTS: In vivo: Maternal Mg deficiency decreased placental Mg content, placental and fetal weights, ratio of fetal:placental weight (P < 0.05), placental Slc7a5 transporter mRNA expression and transplacental nutrient transport (P < 0.05). In vitro: Mg deficiency reduced BeWo nutrient uptake (P < 0.01) and cell proliferation (P < 0.01), and increased oxidative stress (P < 0.01). CONCLUSION: These findings highlight the adverse effects of maternal Mg deficiency on fetal weight and placental function, including transport and proliferation and may explain the fetal growth restriction observed with moderate Mg deficiency in mice.


Subject(s)
Magnesium Deficiency/complications , Magnesium Deficiency/pathology , Placenta/pathology , Placenta/physiology , Pregnancy Complications/pathology , Animals , Cells, Cultured , Female , Fetal Growth Retardation/pathology , Fetal Growth Retardation/physiopathology , Magnesium Deficiency/physiopathology , Mice , Organ Size , Pregnancy , Pregnancy Complications/physiopathology
6.
J Hand Surg Eur Vol ; 41(9): 904-909, 2016 Nov.
Article in English | MEDLINE | ID: mdl-26912393

ABSTRACT

Pain reduction remains the main aim in the treatment of thumb carpometacarpal joint osteoarthritis. We performed a retrospective analysis of a case series of patients with symptomatic thumb carpometacarpal joint arthritis treated with denervation, joint lavage and capsular imbrication. A total of 60 patients participated in this study. Follow-up, including a clinical examination, was performed on 37 patients at a mean of 46 months (range 12 to 81); an additional 23 patients were followed-up by telephone at a mean of 52 months (range 14 to 93) post-operatively. The patients assessed in person showed a significant decrease in pain and a significant improvement in thumb function. The information gathered by telephone gave similar results. The findings of our study indicate that the presented treatment approach could be a good alternative to more invasive surgical options in patients with earlier stages of thumb carpometacarpal joint osteoarthritis. Advantages include the low rate of complications and invasiveness, as well as short recovery times. LEVEL OF EVIDENCE: IV.


Subject(s)
Carpometacarpal Joints , Denervation , Joint Capsule/surgery , Osteoarthritis/surgery , Therapeutic Irrigation , Thumb , Aged , Female , Humans , Male , Middle Aged , Range of Motion, Articular , Retrospective Studies , Treatment Outcome
7.
Ophthalmologe ; 112(12): 1017-21, 2015 Dec.
Article in German | MEDLINE | ID: mdl-26602097

ABSTRACT

Uveal melanomas are the most common malignant tumors of the eye. With modern molecular biological diagnostic methods, such as chromosome 3 typing and gene expression analysis, these tumors can be categorized into highly aggressive (monosomy 3, class II) and less aggressive forms. This molecular biological stratification is primarily important for determining the risk of these tumors as no therapy is currently available that is able to prevent or delay metastases. A randomized study of patients with a poor prognosis (monosomy 3) is currently being carried out in order to determine whether a cancer vaccine prepared from autologous (patient's own) dendritic cells and uveal melanoma RNA can prevent or delay progression and further metastases of this extremely aggressive form of cancer. Inclusion in the uveal melanoma study, which hopes to provide a potential therapeutic option for patients, is only possible if patients are referred to an institution that is able to manufacture and provide this vaccination before the patient is operated on or treated with radiation. Untreated tumor material is necessary for producing the vaccine on an individualized patient basis.


Subject(s)
Cancer Vaccines/therapeutic use , Dendritic Cells/immunology , Melanoma/immunology , Melanoma/therapy , Uveal Neoplasms/immunology , Uveal Neoplasms/therapy , Adult , Aged , Female , Humans , Immunotherapy/methods , Male , Melanoma/diagnosis , Middle Aged , RNA, Neoplasm/immunology , Treatment Outcome , Uveal Neoplasms/diagnosis
8.
Immunol Res ; 63(1-3): 197-208, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26476732

ABSTRACT

Although classically characterized by chronic airway inflammation with eosinophil infiltration, asthma is a complex and multifactorial condition with numerous clinical phenotypes. Epidemiological studies strongly support the link between obesity and asthma and suggest that obesity precedes and promotes asthma development, increases asthma severity, and reduces steroid responsivity. Using a house dust mite (HDM) model of airway hyperresponsiveness in C57BL/6 mice, we examined the effects of diet-induced obesity on allergic airway inflammation and its treatment with dexamethasone. When compared to lean mice treated with HDM, obese-HDM mice had reduced plasma adiponectin, an anti-inflammatory adipokine, lower eosinophil and higher macrophage infiltration into the lungs and bronchoalveolar lavage (BAL) fluid, increased expression of total, M1, and M2 macrophage markers in the lungs, and enhanced Th2 and non-Th2 cytokine expression in the lungs. While Th2-associated responses in obese-HDM mice were suppressed by systemic dexamethasone, several Th2-independent responses, including total and M1 macrophage markers in the lungs, and lung CXC-motif ligand 1 (CXCL1) levels, were not improved following dexamethasone treatment. Thus, HDM combined with obesity promotes mixed localized inflammatory responses (e.g., M1, M2, Th1, and Th2) and shifts the cellular infiltration from eosinophils to macrophages, which are less sensitive to dexamethasone regulation. Because obese asthmatics exhibit more severe symptoms, lack a predominance of Th2 biomarkers, and are predicted to experience more steroid resistance when compared to lean asthmatics, this model could be used to study blunted steroid responses in obese-HDM mice and to define the macrophages found in the lungs.


Subject(s)
Asthma/immunology , Eosinophils/immunology , Macrophages/immunology , Obesity/immunology , Respiratory System/immunology , Adiponectin/blood , Animals , Antigens, Dermatophagoides/immunology , Asthma/complications , Asthma/drug therapy , Cytokines/metabolism , Dexamethasone/administration & dosage , Diet , Disease Progression , Eosinophils/drug effects , Humans , Macrophages/drug effects , Male , Mice , Mice, Inbred C57BL , Obesity/complications , Obesity/drug therapy , Pyroglyphidae/immunology , Th2 Cells/drug effects , Th2 Cells/immunology
9.
Arch Pediatr ; 22(11): 1112-8, 2015 Nov.
Article in French | MEDLINE | ID: mdl-26482185

ABSTRACT

UNLABELLED: French guidelines do not recommend systematic supplementation of vitamin D in children aged 5-10 years old owing to the lack of data on vitamin D status in this age group. Our objective was to assess the prevalence of vitamin D deficiency in these children. METHODOLOGY: Single-center, prospective, epidemiological study including 358 children aged 0-15 years. The endpoint was the concentration of vitamin D. RESULTS: In all, 316 children were divided into four groups according to age: 0-18 months (n=113); 18 months to 5 years (n=103); 5-10 years (n=62); and 10-15 years (n=38). The median concentration of vitamin D decreased with age (P<0.001): 90.2 nmol/L in the group aged 0-18 months; 56.7 nmol/L in the group aged 18 months to 5 years; 49.05 nmol/L in the group aged 5-10 years; and 42.45 nmol/L in the group aged 10-15 years. This corresponds to an increase in the prevalence of vitamin D deficiency in children aged 5-10 years (51.6% vs. 8.8% in the group aged 0-18 months, P<0.001). For children aged 5-10 years, the prevalence of deficiency was greater in the non-supplementation group (75%) compared with the supplementation group (13%; P<0.001). CONCLUSION: This study demonstrates the high prevalence of vitamin D deficiency in children aged 5-10 years and the relationship between supplementation and vitamin D status. It provides an argument in favor of supplementation in children aged 5-10 years in this region and a reconsideration of the French recommendations.


Subject(s)
Vitamin D Deficiency/epidemiology , Adolescent , Child , Child, Preschool , Female , France/epidemiology , Humans , Infant , Infant, Newborn , Male , Prevalence , Prospective Studies , Vitamin D/administration & dosage , Vitamins/administration & dosage
10.
Klin Monbl Augenheilkd ; 232(7): 845-9, 2015 Jul.
Article in German | MEDLINE | ID: mdl-26193117

ABSTRACT

BACKGROUND: Intraocular lymphoma is in most cases a diagnostic challenge. Gold standard is a diagnostic vitrectomy. Vitreous biopsy and transretinal biopsies are therefore employed. METHODS: A retrospective analysis was undertaken of all cases of cytological or histological proven intraocular lymphoma between 2002 and the beginning of 2015 in our clinic. RESULTS: The diagnosis of intraocular lymphoma could be established in 16 cases by cytological or histological analysis. Six patients had previously been treated with steroids in the assumption of uveitis. Five of 16 patients had a systemic or CNS lymphoma in their history. The diagnosis of intraocular lymphoma could be made on the basis of a vitreous biopsy in only in 3 cases. In 7 cases an additional vitrectomy with transretinal biopsy was needed. In 1 case a transretinal biopsy was performed initially and in 1 case a re-transretinal biopsy was needed to establish the diagnosis. Two patients underwent iris biopsy to diagnose a secondary metastatic intraocular lymphoma. One amaurotic eye was diagnosed with intraocular lymphoma after enucleation. DISCUSSION: Due to the high relevance for the diagnosis intraocular lymphoma, when a vitreous biopsy was non-informative, a transretinal biopsy should always be considered in cases of retinal or subretinal involvement.


Subject(s)
Biopsy/methods , Eye Neoplasms/pathology , Lymphoma/pathology , Retina/pathology , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Reproducibility of Results , Retrospective Studies , Sensitivity and Specificity
11.
IEEE Trans Med Imaging ; 33(5): 1023-34, 2014 May.
Article in English | MEDLINE | ID: mdl-24770908

ABSTRACT

2D/3D registration of patient vasculature from preinterventional computed tomography angiography (CTA) to interventional X-ray angiography is of interest to improve guidance in percutaneous coronary interventions. In this paper we present a novel feature based 2D/3D registration framework, that is based on probabilistic point correspondences, and show its usefulness on aligning 3D coronary artery centerlines derived from CTA images with their 2D projection derived from interventional X-ray angiography. The registration framework is an extension of the Gaussian mixture model (GMM) based point-set registration to the 2D/3D setting, with a modified distance metric. We also propose a way to incorporate orientation in the registration, and show its added value for artery registration on patient datasets as well as in simulation experiments. The oriented GMM registration achieved a median accuracy of 1.06 mm, with a convergence rate of 81% for nonrigid vessel centerline registration on 12 patient datasets, using a statistical shape model. The method thereby outperformed the iterative closest point algorithm, the GMM registration without orientation, and two recently published methods on 2D/3D coronary artery registration.


Subject(s)
Coronary Angiography/methods , Coronary Vessels/diagnostic imaging , Imaging, Three-Dimensional/methods , Normal Distribution , Algorithms , Humans , Percutaneous Coronary Intervention , Surgery, Computer-Assisted
12.
Klin Monbl Augenheilkd ; 230(7): 686-91, 2013 Jul.
Article in German | MEDLINE | ID: mdl-23877823

ABSTRACT

Uveal melanoma is the most common primary intraocular tumour in Caucasians. There are approximately 500 new cases of uveal melanoma in Germany per year and the incidence rate peaks at the age of 70 years. Half of all uveal melanoma patients develop metastatic disease, which can be observed even many years after successful treatment of the primary tumour. In most cases the liver is the location of first manifestation. Based on the chromosome 3 status uveal melanomas can be divided into two major classes that differ in their metastatic potential. Tumours with a high risk to metastasise usually show monosomy 3, whereas tumours showing disomy 3 rarely metastasise. If a patient wishes to know about his individual risk, prognostic testing of the primary tumour tissue can be performed after obtaining tumour material via transscleral or transretinal biopsy, or by enucleation. To date results of prognostic testing do not influence therapeutic strategies. Recently, major key genes involved in uveal melanoma development, GNAQ, GNA11, BAP1, SF3B1 and EIF1AX, have been identified. Mutation profiling, in addition to chromosomal 3 analysis, will further refine the classification or subclassification of uveal melanomas and will hopefully influence diagnostic or therapeutic concepts. Hereditary mutations in tumour suppressor gene BAP1 are associated with an increased risk for different tumour entities. Detection of germ line mutations in this tumour suppressor gene should implicate further general screening examinations of the patient to be able to detect these tumour entities. Moreover relatives of these patients should be offered a screening for BAP1 mutation.


Subject(s)
Genetic Markers/genetics , Genetic Testing/methods , Melanoma/genetics , Melanoma/secondary , Molecular Biology/methods , Uveal Neoplasms/diagnosis , Uveal Neoplasms/genetics , Genetic Predisposition to Disease/genetics , Humans , Melanoma/diagnosis
13.
Med Image Anal ; 17(8): 859-76, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23837963

ABSTRACT

Though conventional coronary angiography (CCA) has been the standard of reference for diagnosing coronary artery disease in the past decades, computed tomography angiography (CTA) has rapidly emerged, and is nowadays widely used in clinical practice. Here, we introduce a standardized evaluation framework to reliably evaluate and compare the performance of the algorithms devised to detect and quantify the coronary artery stenoses, and to segment the coronary artery lumen in CTA data. The objective of this evaluation framework is to demonstrate the feasibility of dedicated algorithms to: (1) (semi-)automatically detect and quantify stenosis on CTA, in comparison with quantitative coronary angiography (QCA) and CTA consensus reading, and (2) (semi-)automatically segment the coronary lumen on CTA, in comparison with expert's manual annotation. A database consisting of 48 multicenter multivendor cardiac CTA datasets with corresponding reference standards are described and made available. The algorithms from 11 research groups were quantitatively evaluated and compared. The results show that (1) some of the current stenosis detection/quantification algorithms may be used for triage or as a second-reader in clinical practice, and that (2) automatic lumen segmentation is possible with a precision similar to that obtained by experts. The framework is open for new submissions through the website, at http://coronary.bigr.nl/stenoses/.


Subject(s)
Algorithms , Coronary Angiography/standards , Coronary Stenosis/diagnostic imaging , Pattern Recognition, Automated/methods , Radiographic Image Interpretation, Computer-Assisted/methods , Radiographic Image Interpretation, Computer-Assisted/standards , Tomography, X-Ray Computed/standards , Adult , Aged , Aged, 80 and over , Humans , Middle Aged , Netherlands , Radiographic Image Enhancement/methods , Radiographic Image Enhancement/standards , Reproducibility of Results , Sensitivity and Specificity
14.
Med Image Anal ; 17(6): 698-709, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23628692

ABSTRACT

Accurate alignment of intra-operative X-ray coronary angiography (XA) and pre-operative cardiac CT angiography (CTA) may improve procedural success rates of minimally invasive coronary interventions for patients with chronic total occlusions. It was previously shown that incorporating patient specific coronary motion extracted from 4D CTA increases the robustness of the alignment. However, pre-operative CTA is often acquired with gating at end-diastole, in which case patient specific motion is not available. For such cases, we investigate the possibility of using population based coronary motion models to provide constraints for the 2D+t/3D registration. We propose a methodology for building statistical motion models of the coronary arteries from a training population of 4D CTA datasets. We compare the 2D+t/3D registration performance of the proposed statistical models with other motion estimates, including the patient specific motion extracted from 4D CTA, the mean motion of a population, the predicted motion based on the cardiac shape. The coronary motion models, constructed on a training set of 150 patients, had a generalization accuracy of 1mm root mean square point-to-point distance. Their 2D+t/3D registration accuracy on one cardiac cycle of 12 monoplane XA sequences was similar to, if not better than, the 4D CTA based motion, irrespective of which respiratory model and which feature based 2D/3D distance metric was used. The resulting model based coronary motion estimate showed good applicability for registration of a subsequent cardiac cycle.


Subject(s)
Coronary Angiography/methods , Coronary Stenosis/diagnostic imaging , Coronary Stenosis/physiopathology , Imaging, Three-Dimensional/methods , Models, Cardiovascular , Models, Statistical , Tomography, X-Ray Computed/methods , Cardiac-Gated Imaging Techniques/methods , Computer Simulation , Humans , Image Enhancement/methods , Movement , Reproducibility of Results , Sensitivity and Specificity
15.
Med Image Anal ; 17(5): 515-24, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23602917

ABSTRACT

The distensibility of a blood vessel is a marker of atherosclerotic disease. In this paper we investigate the feasibility of measuring carotid artery distensibility on 4D CTA, both manually and using a new automatic method. On 4D CTA datasets manual (n=38) and automatic (n=76) measurements of the carotid distensibility were performed. A subset (n=10) of the manual annotations were repeated by a second observer. The interobserver variability was assessed using a Bland-Altman analysis and appeared to be too large to reliably measure the distensibility using manual annotation. We compared two versions of the automatic method: one using 3D registration and one using a 4D registration method. The latter resulted in a more smooth deformation over time. The automatic method was evaluated using a synthetic deformation and by investigating whether known relations with cardiovascular risk factors could be reproduced. The relation between distensibility and cardiovascular risk factors was tested with a Mann-Whitney U test. Automatic measurements revealed an association with hypertension whereas the manual measurements did not. This relation has been found by other studies too. We conclude that carotid artery distensibility measurements should be performed automatically and that the method described in this paper is suitable for that. All CTA datasets and related clinical data used in this study can be downloaded from our website (http://ctadist.bigr.nl).


Subject(s)
Angiography/methods , Carotid Arteries/diagnostic imaging , Carotid Artery Diseases/diagnostic imaging , Carotid Artery Diseases/physiopathology , Four-Dimensional Computed Tomography/methods , Radiographic Image Interpretation, Computer-Assisted/methods , Subtraction Technique , Aged , Elastic Modulus , Feasibility Studies , Female , Humans , Male , Pattern Recognition, Automated/methods , Reproducibility of Results , Sensitivity and Specificity , Vascular Resistance
16.
Placenta ; 33(5): 392-8, 2012 May.
Article in English | MEDLINE | ID: mdl-22341339

ABSTRACT

OBJECTIVES: Maternal magnesium sulfate (MgSO4) administration exerts anti-inflammatory and fetal neuroprotective effects. Based on the link between placental inflammation and fetal immune responses, we examined the effect of MgSO4 on LPS-induced inflammation at the maternal-fetal interface. STUDY DESIGN: In vivo model: Pregnant rats (GD19) were injected intraperitoneally with saline, LPS, or MgSO4 plus LPS (n = 6 per group). Rats were euthanized; placentas were assayed for CCL2, IL6, and TNFα and placentas were screened for gene expression. Ex vivo model: Human placental cultures were treated with vehicle, LPS, or MgSO4 plus LPS. Supernatants were assayed for CCL2, IL6, and TNFα. In addition, placental cultures were analyzed for inflammation-related gene expression and NFκ B activation. RESULTS: In vivo model: Maternal LPS administration resulted in pro-inflammatory mediator production within the placenta; maternal MgSO4 treatment significantly attenuated LPS-induced inflammation. Several placental transcripts (APOE, CCL4, CXCL1, and NFκBIZ) differentially expressed following maternal LPS challenge were counter-regulated by MgSO4 treatment. Ex vivo model: LPS promoted human placental inflammation and MgSO4 significantly reduced inflammation induced by LPS. MgSO4 treatment of human placental explants significantly reversed the expression of numerous genes sensitive to LPS regulation and suppressed LPS-induced NFκB activation. CONCLUSIONS: MgSO4 administration inhibited placental inflammation during LPS-mediated maternal infection. Several placental inflammatory genes whose expression was regulated by LPS were reversed by MgSO4 treatment. Our data support the hypothesis that MgSO4 attenuates excessive inflammation at the maternal-fetal interface, which when uncontrolled may compromise neonatal health, including neurologic outcomes.


Subject(s)
Chorioamnionitis/drug therapy , Magnesium Sulfate/therapeutic use , Placenta/drug effects , Pregnancy Complications, Infectious/drug therapy , Tocolytic Agents/therapeutic use , Animals , Female , Gene Expression Regulation/drug effects , Humans , Lipopolysaccharides , Magnesium Sulfate/pharmacology , NF-kappa B/metabolism , Placenta/metabolism , Pregnancy , Rats , Rats, Sprague-Dawley , Tocolytic Agents/pharmacology
17.
Comput Med Imaging Graph ; 36(3): 215-26, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22284861

ABSTRACT

In this paper a method which combines iterative computed tomography reconstruction and coronary centerline extraction technique to obtain motion artifact-free reconstructed images of the coronary arteries are proposed and evaluated. The method relies on motion-vector fields derived from a set of coronary centerlines extracted at multiple cardiac phases within the R-R interval. Hereto, start and end points are provided by the user in one time-frame only. Using an elastic image registration, these points are propagated to all the remaining cardiac phases. Consequently, a multi-phase three-dimensional coronary centerline is determined by applying a semi-automatic minimum cost path based extraction method. Corresponding centerline positions are used to determine the relative motion-vector fields from phase to phase. Finally, dense motion-vector fields are achieved by thin-plate-spline interpolation and used to perform a motion-corrected iterative reconstruction of a selected region of interest. The performance of the method is validated on five patients, showing the improved sharpness of cardiac motion-corrected gated iterative reconstructions compared to the results achieved by a classical gated iterative method. The results are also compared to known manual and fully automatic coronary artery motion estimation methods.


Subject(s)
Cone-Beam Computed Tomography/methods , Coronary Vessels/physiology , Image Processing, Computer-Assisted/methods , Movement/physiology , Algorithms , Cardiac-Gated Imaging Techniques/methods , Humans , Imaging, Three-Dimensional , Radiographic Image Interpretation, Computer-Assisted/methods
18.
Infection ; 40(2): 191-4, 2012 Apr.
Article in English | MEDLINE | ID: mdl-21826435

ABSTRACT

PURPOSE: Bartonella henselae, the cause of cat-scratch disease in humans, may lead to characteristic vision-threatening ocular findings, which importantly indicate diagnosis. METHODS: This is an observational case report of a 6-year-old boy who presented with bilateral stellate maculopathy and lymphadenopathy. RESULTS: After serologic verification of B. henselae infection, systemic azithromycin therapy initiated the full recovery of visual acuity and bilateral complete resolution of stellate exudates during the following months. CONCLUSION: Stellate maculopathy should always include the differential diagnosis of B. henselae infection. In this rare case of bilateral stellate maculopathy, we observed full recovery of function following systemic macrolide therapy.


Subject(s)
Bartonella henselae/isolation & purification , Cat-Scratch Disease/microbiology , Eye Infections, Bacterial/microbiology , Retinitis/microbiology , Animals , Anti-Bacterial Agents/therapeutic use , Azithromycin/therapeutic use , Cat-Scratch Disease/diagnosis , Cat-Scratch Disease/drug therapy , Cats , Child , Diagnosis, Differential , Eye Infections, Bacterial/diagnosis , Eye Infections, Bacterial/drug therapy , Humans , Macula Lutea , Male , Retinitis/diagnosis , Retinitis/drug therapy , Treatment Outcome , Visual Acuity
19.
Int J Comput Assist Radiol Surg ; 7(4): 557-71, 2012 Jul.
Article in English | MEDLINE | ID: mdl-21948075

ABSTRACT

PURPOSE: In clinical practice, both coronary anatomy and myocardial perfusion information are needed to assess coronary artery disease (CAD). The extent and severity of coronary stenoses can be determined using computed tomography coronary angiography (CTCA); the presence and amount of ischemia can be identified using myocardial perfusion imaging, such as perfusion magnetic resonance imaging (PMR). To determine which specific stenosis is associated with which ischemic region, experts use assumptions on coronary perfusion territories. Due to the high variability between patient's coronary artery anatomies, as well as the uncertain relation between perfusion territories and supplying coronary arteries, patient-specific systems are needed. MATERIAL AND METHODS: We present a patient-specific visualization system, called Synchronized Multimodal heART Visualization (SMARTVis), for relating coronary stenoses and perfusion deficits derived from CTCA and PMR, respectively. The system consists of the following comprehensive components: (1) two or three-dimensional fusion of anatomical and functional information, (2) automatic detection and ranking of coronary stenoses, (3) estimation of patient-specific coronary perfusion territories. RESULTS: The potential benefits of the SMARTVis tool in assessing CAD were investigated through a case-study evaluation (conventional vs. SMARTVis tool): two experts analyzed four cases of patients with suspected multivessel coronary artery disease. When using the SMARTVis tool, a more reliable estimation of the relation between perfusion deficits and stenoses led to a more accurate diagnosis, as well as a better interobserver diagnosis agreement. CONCLUSION: The SMARTVis comprehensive visualization system can be effectively used to assess disease status in multivessel CAD patients, offering valuable new options for the diagnosis and management of these patients.


Subject(s)
Cardiac-Gated Imaging Techniques/methods , Coronary Angiography/methods , Coronary Artery Disease/diagnosis , Image Enhancement/methods , Image Interpretation, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Tomography, X-Ray Computed/methods , Aged , Contrast Media , Coronary Artery Disease/diagnostic imaging , Gadolinium DTPA , Humans , Imaging, Three-Dimensional/methods , Male , Middle Aged
20.
Med Image Anal ; 15(4): 477-88, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21419689

ABSTRACT

This paper describes an evaluation framework that allows a standardized and objective quantitative comparison of carotid artery lumen segmentation and stenosis grading algorithms. We describe the data repository comprising 56 multi-center, multi-vendor CTA datasets, their acquisition, the creation of the reference standard and the evaluation measures. This framework has been introduced at the MICCAI 2009 workshop 3D Segmentation in the Clinic: A Grand Challenge III, and we compare the results of eight teams that participated. These results show that automated segmentation of the vessel lumen is possible with a precision that is comparable to manual annotation. The framework is open for new submissions through the website http://cls2009.bigr.nl.


Subject(s)
Angiography/methods , Carotid Arteries/diagnostic imaging , Carotid Stenosis/diagnostic imaging , Imaging, Three-Dimensional/methods , Pattern Recognition, Automated/methods , Radiographic Image Interpretation, Computer-Assisted/methods , Tomography, X-Ray Computed/methods , Algorithms , Humans , Radiographic Image Enhancement/methods , Reproducibility of Results , Sensitivity and Specificity
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