Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 57
Filter
1.
Int J Infect Dis ; 81: 140-148, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30658169

ABSTRACT

BACKGROUND: Pulmonary nocardiosis (PN) is an uncommon but potentially life-threatening infection. Most of our knowledge on PN is derived from case reports and small case series. Increasing incidence rates of PN have been reported recently. The aim of this study was to describe the clinical course of and risk factors for PN in four Western European countries and to estimate population-based annual hospitalization rates. METHODS: This was a retrospective evaluation (1995-2011) of the clinical course of and risk factors for PN in patients at 11 hospitals in four European countries (Germany, Austria, Switzerland, and the Netherlands). Population-based estimates of hospitalization rates for PN in Germany (2005 to 2011) were calculated using official German nationwide diagnosis-related groups (DRG) hospital statistics. RESULTS: Forty-three patients fulfilled stringent criteria for proven (n=8) and probable (n=35) PN; seven had extrapulmonary dissemination. For these 43 patients, the major risk factors for PN were immunocompromising (83.7%) and/or pulmonary (58.1%; as only comorbidity in 27.9%) comorbidities. The median duration of PN targeted therapy was 12 weeks. Distinctive patterns of resistance were observed (imipenem susceptibility: Nocardia farcinica 33.3%; Nocardia asteroides 66.7%). The overall mortality rate was 18.9% (50% in disseminated PN). Over time, annual PN hospitalization rates remained unchanged at around 0.04/100000, with the highest rate among men aged 75-84 years (0.24/100000). CONCLUSIONS: PN is a rare, but potentially life-threatening disease, and mainly affects immunocompromised elderly males. Overall, annual hospitalization rates remained stable between 2005 and 2011.


Subject(s)
Hospitalization/statistics & numerical data , Nocardia Infections/epidemiology , Adult , Aged , Comorbidity , Female , Humans , Immunocompromised Host , Male , Middle Aged , Nocardia Infections/drug therapy , Nocardia Infections/etiology , Retrospective Studies , Risk Factors
2.
Rofo ; 187(5): 380-4, 2015 May.
Article in English | MEDLINE | ID: mdl-25962673

ABSTRACT

PURPOSE: Various technologies have been established for DICOM data exchange in radiology. In addition to the patient CD, online transfers via VPN (virtual private network) or DICOM email are common practice. However, dedicated network solutions are generally not appropriate for data exchange with occasional and spontaneous partners due to missing infrastructure at the partner institutions and/or complex setup procedures. The purpose was to develop a practical solution to complement the established technologies to allow users worldwide to transfer images without registration. MATERIALS AND METHODS: The development of the xPIPE system is based on Java and various software libraries. A client hosted on a website enables sending DICOM data to a receiving system of the hospital. RESULTS: The new xPIPE system creates a gateway to a receiving hospital which is accessible from any point worldwide, giving other hospitals, clinics and patients a simple and secure method to transmit DICOM data without intermediate storage on external servers. CONCLUSION: The system was deployed at the University Hospital Münster and subsequently widely used even without information events and training. Data protection during transfer is ensured by the use of signatures and encryption. From the user's perspective the system has only minor technical requirements and can be used with minimal setup effort.


Subject(s)
Computer Security , Confidentiality , Information Storage and Retrieval/methods , Internet , Medical Record Linkage/methods , Radiology Information Systems/organization & administration , Software , Algorithms , Electronic Health Records/organization & administration , Programming Languages , Software Design , User-Computer Interface
3.
Clin Exp Immunol ; 173(1): 112-20, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23607747

ABSTRACT

Growing evidence suggests a prominent role of the complement system in the pathogenesis of cardio- and cerebrovascular diseases (CVD). Mannan-binding lectin-associated serine proteases (MASPs) MASP-1 and MASP-2 of the complement lectin pathway contribute to clot formation and may represent an important link between inflammation and thrombosis. MBL-associated protein MAp44 has shown cardioprotective effects in murine models. However, MAp44 has never been measured in patients with CVD and data on MASP levels in CVD are scarce. Our aim was to investigate for the first time plasma levels of MAp44 and MASP-1, -2, -3 concomitantly in patients with CVD. We performed a pilot study in 50 healthy volunteers, in stable coronary artery disease (CAD) patients with one-vessel (n = 51) or three-vessel disease (n = 53) and age-matched controls with normal coronary arteries (n = 53), 49 patients after myocardial infarction (MI) and 66 patients with acute ischaemic stroke. We measured MAp44 and MASP-1 levels by in-house time-resolved immunofluorometric assays. MASP-2 and MASP-3 levels were measured using commercial enzyme-linked immunosorbent assay kits. MASP-1 levels were highest in subacute MI patients and lowest in acute stroke patients. MASP-2 levels were lower in MI and stroke patients compared with controls and CAD patients. MASP-3 and MAp44 levels did not differ between groups. MASP or MAp44 levels were not associated with severity of disease. MASP and MAp44 levels were associated with cardiovascular risk factors including dyslipidaemia, obesity and hypertension. Our results suggest that MASP levels may be altered in vascular diseases. Larger studies are needed to confirm our results and elucidate the underlying mechanisms.


Subject(s)
Brain Ischemia/blood , Complement Pathway, Mannose-Binding Lectin , Coronary Disease/blood , Mannose-Binding Protein-Associated Serine Proteases/analysis , Myocardial Infarction/blood , Acute Disease , Aged , Brain Ischemia/immunology , Coronary Disease/immunology , Diabetes Mellitus/blood , Diabetes Mellitus/epidemiology , Dyslipidemias/blood , Dyslipidemias/epidemiology , Enzyme-Linked Immunosorbent Assay , Female , Humans , Hypertension/blood , Hypertension/epidemiology , Male , Middle Aged , Myocardial Infarction/immunology , Overweight/blood , Overweight/epidemiology , Pilot Projects , Risk Factors , Severity of Illness Index , Smoking/blood , Smoking/epidemiology
4.
Sportverletz Sportschaden ; 27(1): 21-7, 2013 Mar.
Article in German | MEDLINE | ID: mdl-23413019

ABSTRACT

BACKGROUND: The aim of this study is to provide a valid and reliable German version of the Tegner activity scale (Tegner-G). The Tegner activity scale assesses on 11 levels the activity in sports (competitive and recreational) and work of patients with anterior cruciate ligament injuries. The English original version was elaborated in Sweden and contains sports that are unknown in German-speaking countries. METHODS: The translation and adaptation was conducted in several steps according to the guidelines in the literature. The validity (discriminative validity and content validity) and (absolute and relative) reliability were determined in 46 patients after reconstruction of the anterior cruciate ligament and in 20 healthy subjects. The patients were divided into an acute group (< 3 months after operation; 11 men; 30.9 ± 8.3 years) and a chronic group (3 - 12 months after operation; 18 men; 31.3 ± 11.6 years). All subjects filled in the scale two times within 3 - 7 days. For the additional determination of the relation between activity and function, they also filled in the German version of the Lysholm score (Lysholm-G). RESULTS: The three groups differed significantly from each other (Kruskal-Wallis test: χ2 = 27.95, p < 0.001; post hoc Mann-Whitney U tests: acute-chronic p < 0.001; acute-control p < 0.001; chronic-control p = 0.003). There was a floor effect in the acute patient group. The intraclass correlation coefficients indicated a high relative reliability (ICC2,1 > 0.9). The minimal detectable change was 1.4 points. The relation between activity (Tegner-G) and function (Lysholm-G) was stronger in the acute than in the chronic patient group (ρ = 0.77 and ρ = 0.60, respectively). CONCLUSION: The psychometric properties of the Tegner-G are comparable to those of the English original version. The Tegner-G is thus valid and reliable for the German-speaking part of Switzerland. The application in other German-speaking countries probably requires adaptations for some of the sports included. The relation between activity and function changes depending on time since operation. This confirms that a comprehensive assessment of the outcome after an anterior cruciate ligament injury requires the separate assessment of both parameters.


Subject(s)
Activities of Daily Living , Anterior Cruciate Ligament Injuries , Anterior Cruciate Ligament/surgery , Knee Injuries/diagnosis , Knee Injuries/surgery , Outcome Assessment, Health Care/methods , Trauma Severity Indices , Adult , Germany , Humans , Male , Recovery of Function , Reproducibility of Results , Sensitivity and Specificity , Treatment Outcome
5.
N Engl J Med ; 368(7): 610-22, 2013 Feb 14.
Article in English | MEDLINE | ID: mdl-23406026

ABSTRACT

BACKGROUND: Subthalamic stimulation reduces motor disability and improves quality of life in patients with advanced Parkinson's disease who have severe levodopa-induced motor complications. We hypothesized that neurostimulation would be beneficial at an earlier stage of Parkinson's disease. METHODS: In this 2-year trial, we randomly assigned 251 patients with Parkinson's disease and early motor complications (mean age, 52 years; mean duration of disease, 7.5 years) to undergo neurostimulation plus medical therapy or medical therapy alone. The primary end point was quality of life, as assessed with the use of the Parkinson's Disease Questionnaire (PDQ-39) summary index (with scores ranging from 0 to 100 and higher scores indicating worse function). Major secondary outcomes included parkinsonian motor disability, activities of daily living, levodopa-induced motor complications (as assessed with the use of the Unified Parkinson's Disease Rating Scale, parts III, II, and IV, respectively), and time with good mobility and no dyskinesia. RESULTS: For the primary outcome of quality of life, the mean score for the neurostimulation group improved by 7.8 points, and that for the medical-therapy group worsened by 0.2 points (between-group difference in mean change from baseline to 2 years, 8.0 points; P=0.002). Neurostimulation was superior to medical therapy with respect to motor disability (P<0.001), activities of daily living (P<0.001), levodopa-induced motor complications (P<0.001), and time with good mobility and no dyskinesia (P=0.01). Serious adverse events occurred in 54.8% of the patients in the neurostimulation group and in 44.1% of those in the medical-therapy group. Serious adverse events related to surgical implantation or the neurostimulation device occurred in 17.7% of patients. An expert panel confirmed that medical therapy was consistent with practice guidelines for 96.8% of the patients in the neurostimulation group and for 94.5% of those in the medical-therapy group. CONCLUSIONS: Subthalamic stimulation was superior to medical therapy in patients with Parkinson's disease and early motor complications. (Funded by the German Ministry of Research and others; EARLYSTIM ClinicalTrials.gov number, NCT00354133.).


Subject(s)
Electric Stimulation Therapy , Parkinson Disease/therapy , Quality of Life , Activities of Daily Living , Adult , Antiparkinson Agents/adverse effects , Antiparkinson Agents/therapeutic use , Combined Modality Therapy , Dopamine Agonists/adverse effects , Dopamine Agonists/therapeutic use , Dyskinesias/etiology , Electric Stimulation Therapy/adverse effects , Female , Humans , Implantable Neurostimulators/adverse effects , Intention to Treat Analysis , Male , Middle Aged , Parkinson Disease/drug therapy , Parkinson Disease/physiopathology , Subthalamic Nucleus , Surveys and Questionnaires , Treatment Outcome
6.
Neurology ; 77(9): 888-95, 2011 Aug 30.
Article in English | MEDLINE | ID: mdl-21849650

ABSTRACT

OBJECTIVE: To examine whether prior statin use affects outcome and intracranial hemorrhage (ICH) rates in stroke patients receiving IV thrombolysis (IVT). METHODS: In a pooled observational study of 11 IVT databases, we compared outcomes between statin users and nonusers. Outcome measures were excellent 3-month outcome (modified Rankin scale 0-1) and ICH in 3 categories. We distinguished all ICHs (ICH(all)), symptomatic ICH based on the criteria of the ECASS-II trial (SICH(ECASS-II)), and symptomatic ICH based on the criteria of the National Institute of Neurological Disorders and Stroke (NINDS) trial (SICH(NINDS)). Unadjusted and adjusted odds ratios (OR) with 95% confidence intervals were calculated. RESULTS: Among 4,012 IVT-treated patients, 918 (22.9%) were statin users. They were older, more often male, and more frequently had hypertension, hypercholesterolemia, diabetes, coronary heart disease, and concomitant antithrombotic use compared with nonusers. Fewer statin users (35.5%) than nonusers (39.7%) reached an excellent 3-month outcome (OR(unadjusted) 0.84 [0.72-0.98], p = 0.02). After adjustment for age, gender, blood pressure, time to thrombolysis, and stroke severity, the association was no longer significant (0.89 [0.74-1.06], p = 0.20). ICH occurred by trend more often in statin users (ICH(all) 20.1% vs 17.4%; SICH(NINDS) 9.2% vs 7.5%; SICH(ECASS-II) 6.9% vs 5.1%). This difference was statistically significant only for SICH(ECASS-II) (OR = 1.38 [1.02-1.87]). After adjustment for age, gender, blood pressure, use of antithrombotics, and stroke severity, the OR(adjusted) for each category of ICH (ICH(all) 1.15 [0.93-1.41]; SICH(ECASS-II) 1.32 [0.94-1.85]; SICH(NINDS) 1.16 [0.87-1.56]) showed no difference between statin users and nonusers. CONCLUSION: In stroke patients receiving IVT, prior statin use was neither an independent predictor of functional outcome nor ICH. It may be considered as an indicator of baseline characteristics that are associated with a less favorable course.


Subject(s)
Hydroxymethylglutaryl-CoA Reductase Inhibitors/administration & dosage , Hydroxymethylglutaryl-CoA Reductase Inhibitors/adverse effects , Stroke/drug therapy , Thrombolytic Therapy/methods , Aged , Aged, 80 and over , Female , Humans , Infusions, Intravenous , Intracranial Hemorrhages/chemically induced , Intracranial Hemorrhages/epidemiology , Male , Middle Aged , Prospective Studies , Stroke/epidemiology , Thrombolytic Therapy/adverse effects , Treatment Outcome
7.
Eur J Cell Biol ; 89(10): 769-77, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20656376

ABSTRACT

Here we demonstrate that physiological concentrations of the thyroid hormones T3 and T4 enhance the KERATIN 15 promoter activity and expression in epithelial stem cells of adult human scalp hair follicles in situ and in vitro. Additionally, T3 and T4 stimulate expression of the immuno-inhibitory surface molecule CD200. Subsequently, T3 and T4 induce apoptosis and differentiation and inhibit clonal growth of these progenitor cells in vitro. These data suggest that human hair follicle bulge-derived epithelial stem cells underlie profound, previously unknown hormonal regulation by thyroid hormones, and show that primary human keratin 15-GFP+ progenitor cells can be exploited to further elucidate fundamental endocrine controls of human epithelial stem cells.


Subject(s)
Apoptosis/physiology , Cell Differentiation/physiology , Epithelial Cells/metabolism , Hair Follicle/metabolism , Keratin-15/metabolism , Stem Cells/metabolism , Triiodothyronine/physiology , Adult , Apoptosis/drug effects , Cell Differentiation/drug effects , Cell Line , Cell Proliferation/drug effects , Cells, Cultured , Epithelial Cells/cytology , Hair Follicle/cytology , Humans , Keratin-15/biosynthesis , Keratin-15/genetics , Organ Culture Techniques , Stem Cells/cytology , Thyroxine/pharmacology , Thyroxine/physiology , Triiodothyronine/pharmacology
9.
Phys Rev Lett ; 102(1): 012301, 2009 Jan 09.
Article in English | MEDLINE | ID: mdl-19257182

ABSTRACT

We report the first measurement of an angular correlation parameter in neutron beta decay using polarized ultracold neutrons (UCN). We utilize UCN with energies below about 200 neV, which we guide and store for approximately 30 s in a Cu decay volume. The interaction of the neutron magnetic dipole moment with a static 7 T field external to the decay volume provides a 420 neV potential energy barrier to the spin state parallel to the field, polarizing the UCN before they pass through an adiabatic fast passage spin flipper and enter a decay volume, situated within a 1 T field in a 2x2pi solenoidal spectrometer. We determine a value for the beta-asymmetry parameter A_{0}=-0.1138+/-0.0046+/-0.0021.

11.
Ann Nutr Metab ; 53(2): 91-5, 2008.
Article in English | MEDLINE | ID: mdl-18946205

ABSTRACT

BACKGROUND: In patients with phenylketonuria (PKU), the carnitine status may be impaired for metabolic or dietary reasons, including low carnitine intake, a deficient synthesis and acylcarnitine production from phenylalanine (Phe) metabolites. METHODS: Free carnitine and acylcarnitine status was assessed in 30 PKU patients, aged 0.5-36 years, mean age 13.8 years. Our cohort was divided into 2 groups according to the preparations of Phe-free amino acids (AA) prescribed, with or without carnitine supplementation. Daily Phe intake, dosage of AA mixtures and body weight were recorded along with measurements of acylcarnitines in blood spots (by tandem mass spectrometry) and serum AA. Control data were obtained from 50 healthy volunteers (aged 0.2-39 years, mean age 14.2. years). Statistical analysis comprised the t test, ANOVA and Pearson's correlation. RESULTS: PKU patients had lower free carnitine (C0) concentrations than controls (25.82 +/- 7.38 vs. 31.28 +/- 6.17 micromol/l; p < 0.001) and lower octanoyl- and decanoylcarnitine. Mean C0 and acylcarnitine concentrations did not differ between PKU patients taking the various protein substitutes with or without carnitine; mean C0 levels in PKU patients receiving AA enriched with carnitine were still lower compared with controls (p < 0.05). CONCLUSIONS: Actual dietary regimens can not completely normalize the carnitine status; therefore, carnitine levels should be given careful consideration in subjects with PKU.


Subject(s)
Carnitine/blood , Carnitine/deficiency , Nutritional Status , Phenylalanine/administration & dosage , Phenylketonurias/diet therapy , Adolescent , Adult , Analysis of Variance , Carnitine/administration & dosage , Case-Control Studies , Child , Child, Preschool , Cohort Studies , Diet, Protein-Restricted , Female , Humans , Infant , Male , Nutritional Requirements , Phenylalanine/blood , Phenylketonurias/blood , Young Adult
12.
J Neurol ; 255(10): 1503-7, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18677634

ABSTRACT

BACKGROUND: Comparisons between younger and older stroke patients including comorbidities are limited. METHODS: Prospective data of consecutive patients with first ever acute ischemic stroke were compared between younger (< or = 45 years) and older patients (> 45 years). RESULTS: Among 1004 patients, 137 (14 %) were < or = 45 years. Younger patients were more commonly female (57 % versus 34 %; p < 0.0001), had a lower frequency of diabetes (1 % versus 15 %; p < 0.0001), hypercholesterolemia (26 % versus 56 %; p < 0.0001), hypertension (19 % versus 65 %; p < 0.0001), coronary heart disease (14 % versus 40 %; p < 0.0001), and a lower mean Charlson co-morbidity index (CCI), (0.18 versus 0.84; p < 0.0001). Tobacco use was more prevalent in the young (39 % versus 26 %; P < 0.0001). Large artery disease (2 % versus 21 %; p < 0.0001), small artery disease (3 % versus 12 %; p = 0.0019) and atrial fibrillation (1 % versus 17 %; p = 0.001) were less common in young patients, while other etiologies (31 % versus 9 %; p < 0.0001), patent foramen ovale or atrial septal defect (44 % versus 26 %; p < 0.0001), and cervical artery dissection (26 % versus 7 %; p < 0.0001) were more frequent. A favorable outcome (mRS 0 or 1) was more common (57.4 % versus 46.9 %; p = 0.023), and mortality (5.1 % versus 12 %; p = 0.009) was lower in the young. After regression analysis, there was no independent association between age and outcome (p = 0.206) or mortality (p = 0.073). Baseline NIHSS score (p < 0.0001), diabetes (p = 0.041), and CCI (p = 0.002) independently predicted an unfavorable outcome. CONCLUSIONS: Younger patients were more likely to be female, had different risk factors and etiologies and fewer co-morbidities. There was no independent association between age and clinical outcome or mortality.


Subject(s)
Ischemia/epidemiology , Stroke/epidemiology , Acute Disease/epidemiology , Adult , Age Factors , Comorbidity , Demography , Female , Humans , Ischemia/etiology , Ischemia/therapy , Male , Middle Aged , Neuropsychological Tests , Regression Analysis , Risk Factors , Stroke/etiology , Stroke/therapy , Treatment Outcome
13.
Dtsch Med Wochenschr ; 132(27): 1469-74, 2007 Jul 29.
Article in German | MEDLINE | ID: mdl-17583831

ABSTRACT

Pernicious anemia and Vitamin B12 deficiency have a wide range of symptoms and are a common finding in the elderly. A 73 year old female is admitted to the hospital because of dyspnea, fatigue and loss of appetite and weight. While previous medical history and physical examination are inconspicuous, laboratory findings show severe pancytopenia with macrocytosis, low reticulocyte count and marked signs of hemolysis. A very low serum level of vitamin B12 and chronic atrophic type A gastritis upon endoscopy with presence of parietal cell antibodies in the serum lead to the diagnosis of pernicious anemia. Complete restitution is achieved by parenteral vitamin B12 substitution. Nowadays, severe pernicious anemia is only rarely seen. The differential diagnosis of pancytopenia (with macrocytic anemia) combined with hemolysis and the essential hints to the diagnosis of pernicious anemia are discussed, and thereby practical aspects including therapy actualized.


Subject(s)
Anemia, Pernicious/diagnosis , Pancytopenia/diagnosis , Vitamin B 12/therapeutic use , Age Factors , Aged , Anemia, Macrocytic/blood , Anemia, Macrocytic/diagnosis , Anemia, Pernicious/blood , Diagnosis, Differential , Female , Folic Acid/administration & dosage , Gastritis, Atrophic/diagnosis , Hemolysis , Humans , L-Lactate Dehydrogenase/blood , Pancytopenia/blood , Vitamin B 12/administration & dosage , Vitamin B 12/blood
14.
Int J Oral Maxillofac Surg ; 32(6): 600-5, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14636609

ABSTRACT

Computed radiography (CR) provides the dynamic exposure range to reveal objects in film areas exposed by very low X-ray exposure. Conventional cephalometric radiographs are normally beam limited to the facial skeleton. The cranial vault and cervical vertebra are collimated and only exposed by extra-focal radiation and scatter. We hypothesize that, on conventional cephalometric radiographs obtained with CR, image data of collimated film areas can be enhanced for reliable performance of Delaire's cephalometric analysis of the entire skull. Therefore the aim of the present study was to compare the reproducibility of landmark placement on normal and underexposed film areas of CR images. Intra- and inter-observer reproducibility of landmark identification was evaluated on 200 randomly selected radiographs by calculating the error radius of repeated landmark placements. A paired-samples t-test revealed differences (P< 0.001) between intra- and inter-observer reproducibility. Intra-observer accuracy was influenced (P< 0.001) by variability of suture obliteration (bregma). Identification of landmarks in areas of extra-focal radiation showed no difference (P> 0.05) from that of landmarks inside the normally exposed area. CR offers the opportunity to perform of a full cranial analysis on a cephalometric radiograph collimated to the facial region.


Subject(s)
Cephalometry/methods , Radiography, Dental, Digital , Humans , Observer Variation , Phantoms, Imaging , Radiographic Image Interpretation, Computer-Assisted , Reproducibility of Results , Tomography, X-Ray Computed/methods
15.
Br J Oral Maxillofac Surg ; 41(2): 102-8, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12694702

ABSTRACT

The survival of loaded implants is critically dependent on their biomechanical stability. We have used a computer-guided navigation technique to evaluate the accuracy of computer-assisted insertion for immediately-loaded implants in minipigs. On the basis of computed tomographical data, the Robodent system was used for preoperative planning and guidance of inserting the implant. An optical tracking system allowed positioning of the implant and immediate prosthetic rehabilitation by inserting it in a plaster model and during the operation. Postoperative computed tomograms (CT) showed that the implants were placed precisely in the preoperatively planned position. The accuracy achieved corresponded well with the spatial resolution of the CT used. Immediate placement of the prefabricated crowns resulted in favourable occlusal positioning. Histological cross-sections showed that the implants were biomechanically stable. The accuracy of insertion of oral implants illustrated here suggests that insertion and prosthetic modelling of implants may benefit from computer-assisted navigation.


Subject(s)
Dental Implantation, Endosseous/methods , Dental Implants , Dental Prosthesis, Implant-Supported , Surgery, Computer-Assisted , Animals , Biomechanical Phenomena , Crowns , Dental Abutments , Dental Prosthesis Design , Male , Mandible/surgery , Microscopy, Electron, Scanning , Models, Dental , Osseointegration , Patient Care Planning , Surgery, Computer-Assisted/instrumentation , Surgery, Computer-Assisted/methods , Swine , Swine, Miniature , Tomography, X-Ray Computed
16.
Rofo ; 175(1): 112-7, 2003 Jan.
Article in German | MEDLINE | ID: mdl-12525991

ABSTRACT

PURPOSE: To evaluate a possible dose reduction in pediatric pelvic radiographs in congenital hip dysplasia using a digital flat-panel system instead of a phosphor-storage system. MATERIALS AND METHODS: During a six-month period, all pediatric patients referred for pelvic radiography for the evaluation of congenital hip dysplasia were randomly assigned to be examined by either a phosphor-storage system or a digital flat-panel system, whereby the latter system was operated with half the radiation dose. Thirty pairs of radiographs were assessed for the visibility of 16 anatomic details and for 5 orthopedic-radiographic measurements (5-point scale with 1 = excellent; three independent observers). The projection indices of Ball and Kommenda and of Tönnis and Brunken were calculated for all radiographs. The Student's t-test was used to compare the flat-panel and the phosphor-storage radiographs for observers' assessments, patients' age and projection indices. RESULTS: In a total of 7560 observations, the scores for the visibility of anatomic details and orthopedic-radiographic measurements were respectively 2.72 and 2.64 for the flat-panel system and 2.93 and 2.79 for the phosphor-storage system. No significant differences were found between both systems (p > 0.05) and between patient age and projection indices (p > 0.05). CONCLUSION: Pediatric pelvic radiographs can be obtained with a digital flat-panel system using half the radiation dose instead of a phosphor-storage system without sacrificing relevant information in the diagnosis of congenital hip dysplasia.


Subject(s)
Hip Dislocation, Congenital/diagnostic imaging , Radiation Protection , Radiographic Image Enhancement/methods , Age Factors , Child , Child, Preschool , Data Interpretation, Statistical , Humans , Infant , Radiation Dosage
17.
Calcif Tissue Int ; 72(2): 156-65, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12370799

ABSTRACT

The purpose of this study was to use high resolution magnetic resonance imaging (HR-MRI) combined with structure analysis to investigate the trabecular structure of the human proximal femur and to compare this technique with bone mineral density (BMD) using dual energy X-ray absorptiometry (DXA) in the prediction of bone strength in vitro. Thirty-one fresh human proximal femur specimens were examined with HR-MRI using a T1-weighted 3D spinecho-sequence in a coronal plane (voxel size: 0.195 x 0.195 x 0.9 mm and 0.195 x 0.195 x 0.3 mm). In these images structure parameters analogous to standard bone histomorphometry were obtained in a femoral head, neck, and trochanteric region of interest (ROI). In addition, BMD measurements were obtained using DXA and finally, all specimens were tested biomechanically in a materials testing machine, and maximum compressive strength (MCS) was determined. Correlations between BMD and MCS were significant (p <0.01) with R-values up to 0.74. Correlating structure parameters and MCS R-values up to 0.69 (P <0.01) were obtained. Using multivariate regression analysis, combining structure parameters and BMD, improved correlations versus MCS substantially (up to R = 0.93; P <0.01). In conclusion, this study showed that in an experimental setting, structure parameters determined in high resolution MR images of the proximal femur correlated significantly with bone strength. The highest correlations, however, were obtained combining BMD and structure measures.


Subject(s)
Femur/anatomy & histology , Magnetic Resonance Imaging/methods , Aged , Bone Density , Bone and Bones/anatomy & histology , Bone and Bones/diagnostic imaging , Compressive Strength , Female , Femur/diagnostic imaging , Femur/physiology , Humans , Male , Radiography , White People
18.
Br J Oral Maxillofac Surg ; 40(2): 96-104, 2002 Apr.
Article in English | MEDLINE | ID: mdl-12180219

ABSTRACT

The outcome of complex craniofacial operations is critically dependent on careful and accurate preoperative planning. Recent advances in computer technology enable the surgeon to do surgical simulations directly on to a computer terminal. We describe the clinical application of a public domain-based computer-aided system in craniofacial surgery. Operation planning was based on clinical investigations and radiological images, with particular use of a virtual three-dimensional surgical simulation. Three patients with complex craniofacial malformations were admitted for orbital correction. Surgical simulation defined numerically the extent of bone movements and the extent of resection areas. Operations were guided by the virtual planning. The outcome was compared with the planning to assess the accuracy of the operative correction. Our first experience confirms that computer-assisted simulation is a reliable and useful tool that improves surgical planning and helps to evaluate the surgical outcome.


Subject(s)
Computer Simulation , Craniofacial Abnormalities/surgery , Craniotomy/methods , Plastic Surgery Procedures/methods , Surgery, Computer-Assisted , Adult , Cephalometry , Child, Preschool , Female , Humans , Imaging, Three-Dimensional , Microphthalmos/surgery , Orbit/abnormalities , Patient Care Planning , Public Sector , Software , Tomography, X-Ray Computed , User-Computer Interface
19.
Rofo ; 173(12): 1099-103, 2001 Dec.
Article in German | MEDLINE | ID: mdl-11740670

ABSTRACT

PURPOSE: In the present study the reduction of artifacts using an extended CT scale technique was examined in 5 vitallium and 5 titanium-aluminium-vanadium tumor prostheses. METHODS: 5 titanium-aluminium-vanadium and 5 vitallium distal femur Mutars(R) tumor prostheses (Mutars(R) - Modular Universal Tumor And Revision System) were implanted in 10 human femur specimens. 110 artifical drill hole lesions of 1 mm, 2 mm, 3 mm, 5 mm and 8 mm diameter were placed in the bone around the hexagonal stem of the tumor prosthesis and furthermore in the proximal part of the femur. All specimens were examined using conventional CT and an extended CT scale technique in a slice thickness of 3 mm. RESULTS: In the proximal part of the femur all drill holes could be detected using 3 mm slices, no artefacts were observed. Along the hexagonal stem smooth lines arising from each hexagonal plane could be observed. This made it impossible to detect a 1 mm drill in 1 vitallium and in 1 titanium-aluminium-vanadium stem. There was no difference between the extended CT scale and conventional CT. CONCLUSION: The extended CT scale did not significantly (p > 0.05, t-test) improve the imaging of artificial drill hole lesions along the hexagonal Mutras(R) stem.


Subject(s)
Bone Neoplasms/surgery , Femoral Neoplasms/surgery , Postoperative Complications/diagnostic imaging , Prosthesis Implantation , Tibia/surgery , Titanium , Tomography, X-Ray Computed , Vitallium , Aged , Aged, 80 and over , Alloys , Artifacts , Bone Neoplasms/diagnostic imaging , Femoral Neoplasms/diagnostic imaging , Humans , Middle Aged , Neoplasm Recurrence, Local/diagnostic imaging , Prosthesis Design , Radiographic Image Enhancement , Sensitivity and Specificity , Tibia/diagnostic imaging
20.
Nuklearmedizin ; 40(6): 193-7, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11797507

ABSTRACT

PURPOSE: To retrospectively evaluate FDG accumulations in major joints in a large series of non-absorption corrected partial body and whole body FDG-PET scans, and to determine the frequency and intensity of accumulation. MATERIALS AND METHODS: 354 consecutive PET partial- and whole body non-transmission corrected scans of patients obtained for tumor staging were examined with respect to FDG accumulations in the acromio-clavicular (AC)-, gleno-humeral-, hip-, knee- and talo-tibial joints. FDG-uptake was graded using a semi-quantitative scale from 0 (no accumulation) to 4 (very strong accumulation comparable to brain uptake). RESULTS: Joint activity of grade 1-2 was noted frequently, while grade 3 was rare, occurring only in the knee and shoulder joints, and grade 4 was inexistent. The 43 patients with grade 3 accumulations or with at least 4 joints showing grade 2 uptake were interviewed, but all denied pain specifically referred to a joint. Joint accumulations were seen in 50% of the acromio-clavicular-, 80% in the glenohumeral-, 50% in the hip-, 90% in the knee and 80% in the talo-tibial joints. The intensities of joint accumulations correlated positively and significantly with patient age, ranging from r = 0.7 and p < 0.05 in the knee to r = 0.96 and p < 0.0001 in the AC joint. CONCLUSIONS: FDG accumulations in the joints in whole body FDG-PET scans are frequent and are very likely not related to symptoms. As there is a strong age correlation, and FDG is known to accumulate in inflammatory lesions, the findings are most likely a result of sub-clinical inflammatory synovial proliferation or other chronic inflammatory processes occurring in aging joints.


Subject(s)
Fluorodeoxyglucose F18/pharmacokinetics , Neoplasms/diagnostic imaging , Radiopharmaceuticals/pharmacokinetics , Tomography, Emission-Computed , Adolescent , Adult , Aged , Aged, 80 and over , Biological Transport , Child , Child, Preschool , Female , Humans , Infant , Joints/diagnostic imaging , Knee Joint/diagnostic imaging , Male , Middle Aged , Neoplasm Staging , Neoplasms/pathology , Tissue Distribution
SELECTION OF CITATIONS
SEARCH DETAIL
...