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1.
Clin Transl Oncol ; 22(8): 1321-1328, 2020 Aug.
Article in English | MEDLINE | ID: mdl-31858434

ABSTRACT

PURPOSE: Whole-body magnetic resonance imaging (WB-MRI) is a radiation-free alternative to the 99mTc-HDP bone scan (BS) for the detection of bone metastasis. The major drawback is the long examination time and application of gadolinium enhancer. The aim of this study is to analyze (i) the performance of WB-MRI versus the BS and (ii) the diagnostic benefit of gadolinium (WB-MRI + Gd) compared to a non-enhanced protocol (NE WB-MRI). METHODS AND MATERIALS: 1256 eligible WB-MRI scans were analyzed retrospectively with a single inclusion criterion, a clinical 12-month follow-up or a biopsy as ground truth. N = 285 patients received both a WB-MRI and a BS within 12 months. All the patients were imaged with a coronal T1w and a STIR, and n = 528 (42%) received an additional T1w-mDixon with gadoteridol (0.1 mmol Gd-DTPA/kg). RESULTS: From 1256 eligible patients, n = 884 (70%) had breast cancer as a primary disease, n = 101(8%) prostate cancer, and n = 77(6%) lung cancer. The sensitivity (Se) and negative predictive value (NPV) of the WB-MRI was 98/99%, significantly higher compared to BS with 82/89%, P < 0.001 Mc Nemar's test. The specificity (Spe) and positive predictive value (PPV) of the WB-MRI and BS was 85/82% and 91/86%, respectively. The interobserver agreement between WB-MRI and BS was 71%, Cohen's kappa 0.42. Analysis of the added diagnostic value of gadolinium revealed Se/Spe/PPV/NPV of 98/93/92/98% for the NE WB-MRI and 99/93/85/100% for the WM-MRI + Gd, P > 0.05 binary logistic regression with Fischer's exact test. CONCLUSION: WB-MRI exceeds the sensitivity of BS without compromising the specificity, even after omitting the gadolinium enhancer.


Subject(s)
Bone Neoplasms/diagnostic imaging , Contrast Media , Heterocyclic Compounds , Magnetic Resonance Imaging/methods , Organometallic Compounds , Whole Body Imaging/methods , Bone Neoplasms/secondary , Breast Neoplasms/pathology , Female , Gadolinium , Humans , Incidental Findings , Lung Neoplasms/pathology , Male , Predictive Value of Tests , Prostatic Neoplasms/pathology , Retrospective Studies , Sensitivity and Specificity
2.
Radiologe ; 52(4): 366-72, 2012 Apr.
Article in German | MEDLINE | ID: mdl-22526116

ABSTRACT

BACKGROUND: A recently developed CAD software which highlights intravascular thrombotic structures from multislice computed tomography (MSCT) data was tested regarding feasibility, interobserver reliability and effect on radiology reports. MATERIAL AND METHODS: The CAD system ImageChecker® CT-Lung was tested in a randomized double-blinded study on 160 MSCT datasets (standardized technical conditions) performed for suspected pulmonary embolism (PE). The CAD data and images were analyzed by three radiologists in an independent and blinded fashion. RESULTS: The data from all 160 cases could be analyzed and 604 CAD prompts were set. Using the CAD analysis significantly more PEs were found in the peripheral pulmonary arterial circulation than described in the initial report. In 38 cases the 3 radiologists in consensus scored the images with the CAD adjunct as PE positive in peripheral vessels, which were initially reported as negative. Despite differences in the evaluation between two radiologists the amended assessment of the imaging data using the CAD softwear was reliable. There was a significant correlation between D-dimer values and the number of embolic structures detected by the CAD analysis. CONCLUSION: The recently developed CAD system is a useful adjunct as second reader to detect subtle emboli in peripheral vessels of MSCT datasets.


Subject(s)
Pulmonary Artery/diagnostic imaging , Pulmonary Embolism/diagnostic imaging , Radiographic Image Enhancement/methods , Radiographic Image Interpretation, Computer-Assisted/methods , Tomography, X-Ray Computed/methods , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Observer Variation , Pattern Recognition, Automated , Reproducibility of Results , Sensitivity and Specificity , Single-Blind Method , Young Adult
3.
Rofo ; 179(1): 53-7, 2007 Jan.
Article in German | MEDLINE | ID: mdl-17203444

ABSTRACT

PURPOSE: To analyze whether currently available CAD systems meet the diagnostic requirements for passing screening tests (first reader CAD) and to analyze whether the additional usage of CAD systems provides significant support for the diagnosing radiologist on the basis of official screening test cases (second reading by CAD). MATERIAL AND METHODS: 200 images of 100 mammographies of 50 patients of an official screening test case collection were analyzed double-blind with and without CAD printouts (iCAD, USA ) by three radiologists: one experienced in breast analysis and CAD application, one experienced in mammography analysis but inexperienced in CAD usage, one with minimal experience with breast analysis and CAD application. All radiologists measured the largest diameter of any malignant mass. The mean value of these calculations was correlated to the largest diameter given by CAD prompts. RESULTS: The mean sensitivity and specificity increased slightly as a result of the additional usage of CAD (1 and 0.6 %, resp.). Both values are not statistically significant. The highest effect was measured for the radiologist with CAD experience, while no effect was measured for the inexperienced radiologist. CAD met the sensitivity requirements but not the specificity criteria (96 and 20.3 %, resp.). The sizes given by CAD prompts corresponded significantly with the real sizes (r = 0.45, p < 0.05). CONCLUSION: A statistically significant effect of the use of CAD could not been detected dependent on the radiological experience or the CAD experience. The effect of CAD on radiologists is still subtle despite the highly sensitive CAD performance due to the high number of false positive prompts and thus does not reach statistical significance. Sizes given by CAD prompts correlate significantly with the real sizes of malignant lesions.


Subject(s)
Mammography , Radiographic Image Interpretation, Computer-Assisted , Breast Diseases/diagnostic imaging , Breast Neoplasms/diagnostic imaging , Diagnosis, Differential , Female , Humans , Observer Variation , Outpatients , Sensitivity and Specificity
4.
Biomed Imaging Interv J ; 3(4): e33, 2007 Oct.
Article in English | MEDLINE | ID: mdl-21614295

ABSTRACT

OBJECTIVE: Cancer cells exhibit altered local dielectric properties compared to normal cells. These properties are measurable as a difference in electrical conductance using electrical impedance scanning (EIS). EIS is at present not sufficiently accurate for clinical routine despite its technological advantages. To modify the technology and increase its accuracy, the factors that influence precision need to be analysed and identified. While size, depth, localisation and invasiveness affect sensitivity, vascularisation might show an increased conductance and thus might affect specificity. SUBJECTS AND METHODS: All patients were investigated with EIS (TransScan TS 2000, Migdal Ha Emek, Israel) Planned DCE-MRI prior to histological clarification were included (295 lesions). Dynamic enhancements were assigned scores after analysis of subtracted images after application of Gd-DTPA. D1: strong enhancement of >100% from initial signal obtained on native T1weighted sequence; D2: moderate enhancement 50-100%; D3: enhancement similar to glandular tissue, <50%; D4: subtle or no enhancement, less then surrounding glandular tissue. RESULTS: 89/113 malignant and 107/182 benign findings were visible by a focal increased conductance and/or capacitance using EIS (Sensitivity 79%, Specificity 59%). DCE-MRI was aborted due to claustrophobia in 17/295 cases. MR was used and out of 278 completed MR examinations, 101/104 malignant and 141/174 benign lesions were correctly diagnosed as benign or malignant leading to a sensitivity of 97% and a specificity of 81%. D1 benign lesions were positive in EIS in 33/55 cases suggesting a specificity of 44.4%. This value increases significantly with decreased vascularity to 68.9% (D2-4; 82/119). Out of 60 fibroadenomatous lesions, 10/23 fibroadenomas in class 1 had no focal increased conductance or capacitance and were thus considered as non-suspicious in EIS. The same result was applicable for the 29/37 benign lesions with a D2-4 contrast uptake (43.5% vs. 78.4%, p<.01). CONCLUSION: Vascularisation influences the measurable conductance at low frequency and therefore partially causes the insufficiently low specificity of EIS. Impedance measurements at frequencies in a range of 0.1 KHz to 1 MHz are required . According to theoretical and in vitro studies this might increase the accuracy of EIS technology. © 2007 Biomedical Imaging and Intervention Journal. All rights reserved.

5.
Anaesthesist ; 55(11): 1172-88, 2006 Nov.
Article in German | MEDLINE | ID: mdl-17004064

ABSTRACT

Thoracic trauma, most often associated with other serious injuries, is the main cause of death in the first 45 years of life. The percentage of chest injuries in multiple trauma, mainly from blunt impact, has remained relatively constant at 80% during the last 30 years. Isolated thoracic injuries comprise only 25% of all trauma cases, 90% of chest injuries are due to blunt impact, while penetrating injuries make up 5-10%. Since 25% of deaths from trauma are attributable to chest injuries, they determine the survival rate in multiple trauma to a significant extent. The pattern of chest injuries is variable, frequently in different combinations comprising rib cage and diaphragm, lung parenchyma, airway and mediastinal organs. This article details the immediate simultaneous diagnostic and therapeutic procedures in the prehospital phase, management in the emergency room, the relative importance of computed tomography, ultrasound examination and endoscopy in the primary diagnostic evaluation and the principles of anaesthetic management of thoracic trauma.


Subject(s)
Emergency Medical Services , Thoracic Injuries/therapy , Adult , Aged , Anesthesia , Blood Substitutes/therapeutic use , Blood Volume/physiology , Child , Child, Preschool , Humans , Infant , Middle Aged , Pain Management , Respiration, Artificial , Respiratory Mechanics/physiology , Thoracic Injuries/etiology , Thoracic Injuries/mortality , Thoracic Injuries/surgery , Wounds, Nonpenetrating/etiology , Wounds, Nonpenetrating/therapy
6.
Rheumatol Int ; 26(12): 1084-90, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16736163

ABSTRACT

The objective of the study is to evaluate multi-site quantitative ultrasound (QUS) in comparison to dual energy X-ray absorptiometry (DXA) considering the effects of body mass index (BMI) and disease activity on measurements in patients suffering from rheumatoid arthritis (RA). Sixty-eight patients underwent a cross-sectional analysis of bone mineral density measured by DXA (lumbar spine, total femur) and speed of sound estimated by QUS (phalanx III, distal radius). The short-term precision of QUS was investigated with regard to BMI of healthy individuals and with regard to the level of disease activity in patients suffering from RA. The patients with RA were divided into two BMI groups as well as into low and advanced disease activity groups. The short-term precision of QUS-SOS ranged from 0.90 to 2.55% (healthy controls) and from 0.64 to 1.89% (patients with RA). The association between DXA and QUS parameters were limited in the case of advanced disease activity and pronounced BMI. Low QUS-SOS was observed for advanced disease activity group (QUS-SOS phalanx: -2.5%; QUS-SOS distal radius: -2.1%) in comparison to low disease activity group, whereas only a slight change of DXA parameters was observed. DXA-BMD and QUS parameters revealed higher values with pronounced BMI. The system shows only a short-term precision with limitations in healthy controls with accentuated BMI, as well as in patients with active RA. The application of multi-site QUS seems to be restricted for patients with active inflammation based on soft tissue alteration in RA and for healthy individuals with pronounced body mass.


Subject(s)
Arthritis, Rheumatoid/diagnosis , Body Mass Index , Absorptiometry, Photon , Aged , Arthritis, Rheumatoid/diagnostic imaging , Arthrography , Female , Femur/diagnostic imaging , Finger Phalanges/diagnostic imaging , Humans , Joints/diagnostic imaging , Male , Middle Aged , Reproducibility of Results , Ultrasonography
7.
Calcif Tissue Int ; 78(1): 25-34, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16397736

ABSTRACT

The development of secondary osteoporosis in rheumatoid arthritis (RA) has recently become well recognized, characterized by demineralization at axial and in particular periarticular peripheral bone sites. Our aim was to evaluate multisite quantitative ultrasound (QUS) compared to digital X-ray radiogrammetry (DXR) by the quantification of cortical bone loss dependent on the severity of RA. Fifty-three patients with verified RA underwent QUS measurements (Sunlight Omnisense 7000) with estimation of the speed of sound (QUS-SOS) at the distal radius and at the phalanx of the third digit. Also, bone mineral density (DXR-BMD) and metacarpal index (DXR-MCI) were estimated on metacarpals II-IV using DXR technology. Additionally, Larsen score and Steinbroker stage were assessed. Disease activity of RA was estimated by disease activity score 28 (DAS 28). For the group with minor disease activity (3.2 5.1), QUS-SOS of the radius revealed a significant correlation to DXR-BMD (R = 0.71) and DXR-MCI (R = 0.84), whereas for QUS-SOS (phalanx) no significant association to the DXR parameters was shown. The DXR parameters and, to a lesser extent, the QUS data also demonstrated pronounced declines in the case of accentuated disease activity (DAS > 5.1). Both DXR-BMD (-25.9 %, P < 0.01) and DXR-MCI (-38.6 %, P < 0.01) revealed a notable reduction dependent on the severity of RA. Otherwise, QUS-SOS marginally decreased, with -2.6% (radius) and -3.9% (phalanx). DXR revealed a significant reduction of DXR-BMD as well as DXR-MCI dependent on the severity of RA and surpassed multisite QUS as a promising diagnostic tool.


Subject(s)
Absorptiometry, Photon/methods , Arthritis, Rheumatoid/diagnostic imaging , Bone Density , Radiographic Image Enhancement/methods , Ultrasonics , Adult , Aged , Aged, 80 and over , Arthritis, Rheumatoid/metabolism , Arthritis, Rheumatoid/pathology , Cross-Sectional Studies , Female , Germany , Humans , Linear Models , Male , Metacarpal Bones/diagnostic imaging , Metacarpal Bones/metabolism , Metacarpal Bones/pathology , Middle Aged , Radius/diagnostic imaging , Radius/metabolism , Radius/pathology , Severity of Illness Index
8.
Arthritis Rheum ; 52(12): 3850-9, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16320332

ABSTRACT

OBJECTIVE: To evaluate digital x-ray radiogrammetry (DXR) and the Radiogrammetry Kit program as new diagnostic tools for quantifying disease-related periarticular osteoporosis and for measuring joint space narrowing according to the severity and duration of rheumatoid arthritis (RA). METHODS: Using DXR, we performed computerized calculations of bone mineral density (BMD) and the metacarpal index (MCI) in 258 patients with active RA. Using the Radiogrammetry Kit program, we also performed semiautomated measurements of joint space width (JSW) at the second through the fifth metacarpophalangeal (MCP) joints in these patients. RESULTS: All correlations between the different parameters of both techniques (BMD and the MCI as measured by DXR and MCP JSW as measured by the Radiogrammetry Kit) were significant (0.36 < or = R < or = 0.63; P < 0.01). As expected, a significant negative association was shown between the different MCP JSW results and the results of all scoring methods (-0.67 < or = R < or = -0.29). The BMD and the MCI measured by DXR both decreased significantly between Steinbrocker stage I and stage IV (by 32.7% and 36.6%, respectively; both P < 0.01). Reductions in the overall (mean) MCP JSW varied from 35.3% (Larsen score) to 52.9% (Steinbrocker stage). Over a period of 6 years, we observed relative decreases in BMD and the MCI as measured by DXR (32.1% and 33.3%, respectively), as well as in the overall (mean) MCP JSW (23.5%), and these were pronounced in early RA (duration <1 year). In addition, excellent reproducibility of DXR and Radiogrammetry Kit parameters was verified (coefficients of variation <1%). CONCLUSION: DXR with the integrated Radiogrammetry Kit program could be a promising, widely available diagnostic tool for supplementing the different RA scoring methods with quantitative data, thus allowing an earlier and improved diagnosis of RA and more precision in determining disease progression.


Subject(s)
Absorptiometry, Photon/methods , Arthritis, Rheumatoid/diagnostic imaging , Bone Density , Metacarpophalangeal Joint/diagnostic imaging , Radiographic Image Enhancement/methods , Adolescent , Adult , Aged , Aged, 80 and over , Cross-Sectional Studies , Disability Evaluation , Female , Humans , Longitudinal Studies , Male , Middle Aged , Severity of Illness Index
9.
Rofo ; 177(4): 524-9, 2005 Apr.
Article in German | MEDLINE | ID: mdl-15838757

ABSTRACT

PURPOSE: To determine whether quantitative ultrasound (QUS) parameters speed of sound (SOS) and broadband ultrasound attenuation (BUA) on the calcaneus are different between athletic children and a reference population. PATIENTS AND METHODS: From a college of physical education, 177 children and adolescents (121 boys and 56 girls, age range from 11 to 18 years) were included in this study. QUS was performed on the calcaneus using the Saharatrade mark device (Hologic, USA). SOS and BUA were estimated. Regional reference values of 3299 children were used to determine significant differences between athletes and reference population. The influence of activitiy level, age, height, and weight was estimated using correlation analysis. RESULTS: Sportsmen showed significant (p < 0.05) higher values of the QUS parameters (SOS 1581.1 m/s; BUA 69.7 dB/MHz) compared to the reference data (SOS 1563.9 m/s; BUA 64.2 dB/MHz). Significant correlation was observed between BUA and the level of activity, age, weight, and height (p < 0.01) and between SOS and weight and height (p < 0.05). In the group of soccer players and athlets, significant correlation was found between BUA vs. age and BUA vs. weight (p < 0.05). Furthermore, significant corelation was observed between BUA vs. age and weight in judokas and wrestlers. For the level of activity, a significant correlation to BUA was only found in the group of judokas and wrestlers (p < 0.01). CONCLUSION: An increase in quantitative ultrasound parameters on the calcaneus occurs in children and adolescents with increased physical activity.


Subject(s)
Calcaneus/diagnostic imaging , Calcaneus/physiology , Image Interpretation, Computer-Assisted/methods , Motor Activity/physiology , Sports/physiology , Sports/statistics & numerical data , Adolescent , Child , Female , Germany/epidemiology , Humans , Male , Sex Distribution , Ultrasonography
10.
Rheumatol Int ; 25(6): 457-64, 2005 Aug.
Article in English | MEDLINE | ID: mdl-15761729

ABSTRACT

OBJECTIVES: To investigate the potential of a new osteogeometric technology based on digital X-ray radiogrammetry (DXR) as a diagnostic tool for quantification of severity-dependent osteoporosis, and to distinguish between inflammation-mediated and corticoid-induced variations of bone mineralisation in patients suffering from rheumatoid arthritis. METHODS: Ninety-six patients (duration of disease: <18 months) underwent retrospective calculations of bone mineral density (DXR-BMD) and metacarpal index (MCI) by DXR, which were calculated from plain radiographs of the non-dominant hand. For comparison, pQCT-calculated BMD (total, cortical-subcortical and trabecular partition of bone tissue) was done on the distal radius. Severity was classified using Ratingen Score by two independent radiologists, and divided into three main groups. In addition, the patients were separated into those with corticoid medication (n=44; 5 mg/day over a half year period) and a control group (n=52) without any corticoid therapy. RESULTS: Correlations between DXR-BMD and MCI versus pQCT parameters were all significant (0.36

Subject(s)
Absorptiometry, Photon/methods , Arthritis, Rheumatoid/diagnostic imaging , Bone Density , Osteoporosis/diagnostic imaging , Radiographic Image Enhancement/methods , Tomography, X-Ray Computed/methods , Adult , Aged , Aged, 80 and over , Arthritis, Rheumatoid/complications , Arthritis, Rheumatoid/metabolism , Early Diagnosis , Female , Humans , Male , Metacarpal Bones/metabolism , Metacarpal Bones/pathology , Middle Aged , Osteoporosis/etiology , Osteoporosis/metabolism , Retrospective Studies
11.
Rofo ; 177(2): 197-203, 2005 Feb.
Article in German | MEDLINE | ID: mdl-15666227

ABSTRACT

PURPOSE: In addition to many established osteodensitometric techniques, digital radiogrammetry (DXR) is considered to be a reliable method for measuring the cortical bone mineral density (DXR-BMD). This study investigates the influence of body constitution on BMD of healthy adults as calculated by DXR. MATERIALS AND METHODS: In a prospective study, 246 adults without bone affecting diseases in their clinical history underwent DXR for analysis and calculations of bone mineral density and determination of metacarpal index (MCI) and porosity index (PI). Height, weight and body mass index (BMI) were recorded for each patient. RESULTS: For all individuals and for all BMI subgroups, both height (0.55 < R < 0.70, p < 0.01) and body weight (0.56 < R < 0.78, p < 0.01) correlated closely with DXR-BMD. Only in the over-weight group, no significant correlation was found between body weight and DXR-BMD. In addition, a significant reduction of the relative DXR-BMD and MCI values was observed between the over-weight and the under-weight group as well as between normal-weight and under-weight individuals (p < 0.01). Otherwise, cortical porosity decreased with increasing body weight. CONCLUSION: Similar to Dual Energy X-ray Absorptiometry-based studies (DXA), digital radiogrammetry measures an increase in BMD with increasing body weight. Therefore DXR, which provides a precise technique without influence of soft tissue, seems to be a promising technique for quantifying marginal alterations in cortical BMD as well for following the course of osteoporosis.


Subject(s)
Absorptiometry, Photon/methods , Body Mass Index , Bone Density , Adult , Anthropometry , Female , Functional Laterality , Hand/diagnostic imaging , Humans , Male , Prospective Studies , Radiographic Image Enhancement
12.
Z Rheumatol ; 63(6): 473-82, 2004 Dec.
Article in German | MEDLINE | ID: mdl-15605213

ABSTRACT

PURPOSE: To investigate a new bone densitometric technology based on digital radiogrammetry (DXR) with respect to its ability to measure severity-dependent variations of bone mineral density (BMD) in patients with rheumatoid arthritis and to differentiate between corticoid-induced and periarticular bone mineral density loss. PATIENTS AND METHODS: A total of 153 randomly selected patients suffering from verified rheumatoid arthritis underwent digitally performed plain radiographs of the non-dominant hand and also measurements of dual-energy X-ray absorptiometry (DXA) regarding total femur and lumbar spine in 102 patients and peripheral quantitative computed tomography (pQCT) regarding the distal radius in 51 patients. Using DXR the radiographs of the non-dominant hand were analyzed for cortical bone mineral density calculation. The severity was classified in the DXA group using the Ratingen score. Furthermore, both study populations were divided into patients with and without corticoid therapy. RESULTS: Correlations between BMD determined by DXR and by DXA (R=0.44 for lumbar spine and R=0.61 for total femur) versus pQCT (0.46

Subject(s)
Absorptiometry, Photon , Arthritis, Rheumatoid/drug therapy , Bone Density/drug effects , Bone Diseases, Metabolic/chemically induced , Image Processing, Computer-Assisted , Mathematical Computing , Tomography, X-Ray Computed , Adult , Aged , Arthritis, Rheumatoid/diagnostic imaging , Bone Diseases, Metabolic/diagnostic imaging , Diagnosis, Differential , Female , Femur/diagnostic imaging , Femur/drug effects , Humans , Long-Term Care , Lumbar Vertebrae/diagnostic imaging , Lumbar Vertebrae/drug effects , Male , Metacarpus/diagnostic imaging , Metacarpus/drug effects , Middle Aged , Osteoporosis/chemically induced , Osteoporosis/diagnostic imaging , Sensitivity and Specificity , Statistics as Topic
13.
Skeletal Radiol ; 33(12): 698-703, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15480639

ABSTRACT

OBJECTIVE: To evaluate the reproducibility of imaging and analysis for bone mineral density (BMD) determination using digital computer-assisted X-ray radiogrammetry (DXR; Pronosco X-posure, version V.2, Sectra Pronosco, Denmark); to verify potential factors that influence BMD extrapolation such as tube voltage, film-focus distance (FFD), film quality and brand (Kodak T-MAT-Plus, Konika SRH, Agfa Scopix), imaging technology (conventional, digital), imaging system (Kodak, Agfa) and exposure level (mAs); and to clarify whether DXR analysis based on printouts of digital images is comparable to analysis of conventional images. DESIGN AND PATIENTS: The hand of a cadaver was X-rayed using varied parameters: 4-8 mAs, 40-52 kV, 90-130 cm FFD. Radiographs under standardised conditions were performed 10 times using a conventional machine (Philips Super 80 CP) and the printouts of a digital system (Digital Diagnost Philips Optimus) for the analysis of reproducibility. One image was scanned and analysed 10 times additionally for imaging reproducibility. RESULTS: Reliability error of the system for the imaging process using conventional radiographs-rays was 0.49% (standard conditions: 6 mAs, 40 kV, 1 m FFD), using printouts of digital images was 2.89% (4 mAs, 42 kV, 1 m FFD) and regarding the analysis process was 0.22%. BMD calculation is not affected by alterations in FFD (precision error 1.21%), mAs (0.83%) or film quality/brand (0.38%), but differs significantly depending on tube voltage (2.70%). The system was not able to analyse conventional images with tube voltages of 49/52 kV. CONCLUSION: DXR technology is stable with most of the tested parameters. Normative data should exclusively be used for calculations using similar tube voltage or correction factors. All other parameters had no significant influence on the BMD calculation. Reproducibility is high. For technical reasons it is not recommended to use the printouts of digital images for BMD determination.


Subject(s)
Hand/diagnostic imaging , Image Processing, Computer-Assisted , Radiographic Image Enhancement , Bone Density , Hand/physiology , Humans , Reproducibility of Results
14.
Eur Spine J ; 13(2): 147-51, 2004 Mar.
Article in English | MEDLINE | ID: mdl-14634853

ABSTRACT

Conjoined lumbosacral nerve roots (CLNR) are the most common anomalies involving the lumbar nerve structures which can be one of the origins of failed back syndromes. They can cause sciatica even without the presence of a additional compressive impingement (such as disc herniation, spondylolisthesis or lateral recess stenosis), and often congenital lumbosacral spine anomalies (such as bony defects) are present at the "conjoined sheaths". This congenital anomaly has been reported in 14% of cadaver studies, but myelographic or computed tomographic studies have revealed an incidence of approximately 4% only. Diagnostic methods such as magnetic resonance imaging (MRI) are helpful for determination of the exact anatomical relations in this context. We present five typical cases of conjoined nerve roots observed during a 1 year period, equivalent to 6% of our out-patients without a history of surgical treatment on the lumbar spine. In all cases with suspicious radiological findings MRI or lumbar myelography combined with CT and multiplanar reconstructions is recommended.


Subject(s)
Low Back Pain/etiology , Low Back Pain/pathology , Magnetic Resonance Imaging , Spinal Nerve Roots/abnormalities , Adolescent , Humans , Intervertebral Disc Displacement/diagnostic imaging , Intervertebral Disc Displacement/pathology , Low Back Pain/diagnostic imaging , Lumbosacral Region , Male , Middle Aged , Myelography , Sciatica/diagnostic imaging , Sciatica/etiology , Sciatica/pathology , Spinal Nerve Roots/diagnostic imaging
15.
Eur Radiol ; 14(4): 631-7, 2004 Apr.
Article in English | MEDLINE | ID: mdl-14600776

ABSTRACT

The aim of this study was to investigate a new bone densitometric technology based on digital radiogrammetry (DXR) with respect to its ability to measure severity-dependent variations of bone mineralization in patients with rheumatoid arthritis. One hundred six randomly selected patients suffering from verified rheumatoid arthritis underwent digitally performed plain radiographs of the non-dominant hand and measurements of dual-energy X-ray absorptiometry (DXA) regarding total femur and lumbar spine. Using DXR the radiographs were analyzed retrospectively for bone mineral density (BMD) calculation. The severity was classified using Larsen score and Steinbroker stage blinded by two radiologists. A third radiologist reviewed the incongruently scored cases. Mean values of calculated parameters changed as follows from Larsen 1 to Larsen 5: Bone mineral density (DXR-BMD) decreased from 0.55 to 0.44 g/cm2 (p=0.000), DXR-MCI decreased from 0.44 to 0.33 (p=0.001), DXA-BMD (total femur) decreased from 0.92 to 0.78 g/cm2 (p=0.090) and DXA-BMD (lumbar spine) decreased from 0.91 to 0.84 g/cm2 (p=0.595). Similar results were verified for the Steinbroker stage. The relative decrease of BMD measured by DXR between the highest and lowest score was 20% for Steinbroker stage and Larsen score (p<0.05). The relative decrease of BMD using DXA revealed not such a significant result. Similar results were verified for metacarpal index (estimated by DXR). Correlations between BMD determined by DXR and by DXA were all significant (R=0.45 for lumbar spine and R=0.59 for total femur). Consequently, less than 35% of the DXR-BMD value is explainable by corresponding DXA values. The DXR-based BMD calculation seems to be able to distinguish severity and progress of the disease in contrast to those of DXA at lumbar spine and total femur.


Subject(s)
Absorptiometry, Photon , Arthritis, Rheumatoid/diagnostic imaging , Bone Density , Radiographic Image Enhancement , Female , Femur/diagnostic imaging , Hand/diagnostic imaging , Humans , Lumbar Vertebrae/diagnostic imaging , Male , Middle Aged
16.
Eur Radiol ; 14(3): 394-401, 2004 Mar.
Article in English | MEDLINE | ID: mdl-14517688

ABSTRACT

The aim of this study was to evaluate potential diagnostic relevance of blooming effect for verification of suspicious breast lesions in MR mammography (MRM). The MRM examinations of 1035 patients, all following the same imaging protocol (from 1994 to 2001) were retrospectively evaluated by two experienced radiologists in consensus. A total of 817 lesions showed a focal enhancement; of these, 793 were histologically verified after surgical intervention so that 514 malignant and 279 benign lesions could be evaluated. Using a 1.5-T Gyroscan ACS II-imager (Philips, Hamburg, Germany) and a double breast coil with the patient lying in a prone position, 0.1 mmol/kgbw Magnevist (Schering, Berlin, Germany) were injected into the cubital vein to obtain dynamic axial and coronal T1-weighted fast-field-echo images every minute up to 7 min after bolus injection. Blooming sign describes a progradient unsharpness of lesion borders initially sharply shaped and fast enhancing 7 min after bolus injection; 324 of 514 (63.0%) malignant lesions and 41 of 279 (14.7%) benign lesions revealed a blooming sign (sensitivity 63.0%, specificity 85.3%, accuracy 70.9%, positive predictive value 88.8%, negative predictive value 56.0%). Forty-one of 279 benign lesions showed a blooming sign; of these, there were 4 of 86 (4.7%) fibroadenomas, 2 of 21 (9.5%) phylloides tumours, 11 of 38 (28.9%) papillomas, 3 of 9 (33.3%) radial scars, 2 of 19 (10.5%) mastitis, 1 of 4 (25%) galactophoritis, 1 of 3 (33.3%) ADH and 19 of 99 (17.2%) mastopathic proliferations, respectively. Blooming sign is a phenomenon which should be taken into account when diagnosing MR mammographies because it might increase the ability to discriminate uncertain breast lesions; however, this effect can only be used as an additional item to other well-known effects such as plateau, washout and cancer corner.


Subject(s)
Breast Neoplasms/diagnostic imaging , Breast Neoplasms/pathology , Magnetic Resonance Imaging , Mammography/methods , Adult , Female , Humans , Mammography/statistics & numerical data , Predictive Value of Tests , Reproducibility of Results , Retrospective Studies , Sensitivity and Specificity
17.
Rofo ; 175(9): 1225-31, 2003 Sep.
Article in German | MEDLINE | ID: mdl-12964078

ABSTRACT

PURPOSE: To assess the capability of the computer assisted detection (CAD) system to classify calcifications that are histologically verified as malignant and benign or are proven benign by magnification and follow up mammography. MATERIALS AND METHODS: Three groups of microcalcifications (MC) with and without associated masses were enrolled in the study. The cancer group included 141 screen-detected breast cancer cases. One benign group comprised 109 cases with histologically benign specimens obtained through a minimally invasive breast biopsy. A second benign group included 72 lesions with MC that appeared benign on magnification/compression views and were confirmed to be benign on follow-up mammograms over a period of at least 1.5 years. All mammograms were evaluated with a CAD system (Second Look version 3.5, CADx Medical Systems, Canada). RESULTS: CAD correctly detected 125 of 141 (89 %) cancer cases. Of the 16 false negative cases, CAD marked the location of the MC (which were associated with malignant mass) with a mass mark in 12 cases. For benign cases, CAD did not correctly mark the microcalcifications in 59 of the 109 lesions confirmed benign histologically (54.1 %) and in 39 of the 72 lesions established benign mammographically (54.2 %). Adenosis introduced the highest rate of falsely marked microcalcifications (62 %). CONCLUSION: Due to its limited specificity, CAD can still not be recommended for the primary classification of microcalcifications as malignant or benign. Nevertheless, the low false negative rate and rather high detection rate of malignant findings indicate some value of CAD for an independent second reading.


Subject(s)
Breast Diseases/diagnostic imaging , Breast Neoplasms/diagnostic imaging , Mammography , Radiographic Image Interpretation, Computer-Assisted , Adenocarcinoma/diagnostic imaging , Adenocarcinoma, Mucinous/diagnostic imaging , Biopsy , Breast/pathology , Breast Diseases/pathology , Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/diagnostic imaging , Carcinoma, Lobular/diagnostic imaging , Carcinoma, Papillary/diagnostic imaging , Diagnosis, Differential , Female , Fibroadenoma/diagnostic imaging , Fibrocystic Breast Disease/diagnostic imaging , Fibrosis/diagnostic imaging , Humans , Hyperplasia , Papilloma/diagnostic imaging , Retrospective Studies
18.
Rofo ; 175(4): 495-501, 2003 Apr.
Article in German | MEDLINE | ID: mdl-12677504

ABSTRACT

PURPOSE: To evaluate the potential diagnostic value of quantification of contrast enhanced power Doppler sonography in breast lesions. MATERIALS AND METHODS: Before and after bolus application of 300 mg/ml of the contrast agent Levovist (Schering, Germany), 76 randomly selected equivocal breast lesions (37 benign, 39 malignant) underwent power Doppler sonography. The data were acquired with a 7.5 MHz linear array transducer (Sonoline Versa Pro and Sonoline Elegra Plus, Siemens, Germany). Following postprocessing digitalization, color pixel density (CPD) and dynamic contrast enhancement were calculated and compared using different regions of the tumor (entire lesion, center and periphery). RESULTS: A measurable pixel signal prior to the application of the contrast agent was observed in 12 of 37 benign and in 18 of 39 malignant lesions (32.4 % and 46.2 %, respectively). After administration of the contrast agent, the lesions with measurable signal increased to 20 of 37 (54 %) and 25 of 39 (64.1 %), respectively. No statistically significant difference of dignity-related signal intensity could be verified before or after administration of the contrast agent. Maximum CPD and relative increase in pixel density after contrast medium was appreciably higher in the center of malignant lesions than in corresponding regions of benign lesions. CONCLUSION: Quantification of color pixel density is rather nonspecific for the discrimination of equivocal breast lesions and not suitable for clinical routine. Signal detection and quantification of color coded pixels enable comparison of dynamic contrast enhancement.


Subject(s)
Breast Diseases/diagnostic imaging , Breast Neoplasms/diagnostic imaging , Contrast Media/administration & dosage , Polysaccharides , Ultrasonography, Doppler, Color/statistics & numerical data , Ultrasonography, Mammary/statistics & numerical data , Adult , Aged , Aged, 80 and over , Breast Neoplasms/blood supply , Diagnosis, Differential , Female , Humans , Image Processing, Computer-Assisted/statistics & numerical data , Mathematical Computing , Middle Aged , Neovascularization, Pathologic/diagnostic imaging , Prospective Studies , Regional Blood Flow/physiology , Sensitivity and Specificity
19.
Rofo ; 175(3): 366-73, 2003 Mar.
Article in German | MEDLINE | ID: mdl-12635013

ABSTRACT

PURPOSE: To determine broadband ultrasound attenuation (BUA) and speed of sound (SOS) on the os caicis in asthmatic children. To correlate these findings with sex, age, weight and height, topical steroid intake, and asthma severity grade (ASG). PATIENTS AND METHODS: 178 children (ASG 1 - 3)/(98 m, 80 f; mean age 11.9 +/- 3.1 y) were consecutively chosen from 4/00 to 9/01. Children with any other chronic disease were excluded. BUA and SOS were measured using SAHARA (Hologic lnc. Waltham, USA). Regional normative BUA and SOS data of 3 299 children (obtained with the same system), were used to calculate age-, weight- and height-matched standard-deviation-scores (SDS) for both sexes. Asthma severity grade and steroidal intake were determined. The highest topical steroid dosage was 500 micro g Fluticasone or 800 micro g Budesonide per day. RESULTS: 10/178 children were small and 7/178 tall per age (5.6 %/3.9 %), 11/178 children were light (6.2 %) and 9 heavy per age (5.0 %). 19 and 45 children had reduced BUA and SOS values, respectively. The following rates of reduced values were observed: girls: BUA 15.0 % (12/80), SOS 25.0 % (20/80); boys: BUA 7.1 %, SOS 25.5 % (7/98 and 25/98). Sexual differences were not significant. Reduced SOS-values were associated with higher severity and occurred significantly more frequent at children under steroidal intake (0.09 vs. 0.25 [BUA] and - 0.37 vs. - 0.07 [SOS]). CONCLUSION: Following our results an increase incidence of reduced speed of sound occurs in asthmatic children which is attributed to asthma severity and seems to be negatively influenced even by topically applied low dose steroids. This could be attributed to a steroid induced collagen synthesis deficiency followed by a reduced bone elasticity. Further studies, especially using a longitudinal study design are required to verify these findings.


Subject(s)
Asthma/diagnostic imaging , Adolescent , Adrenal Cortex Hormones/administration & dosage , Adrenal Cortex Hormones/therapeutic use , Age Factors , Androstadienes/administration & dosage , Androstadienes/therapeutic use , Anti-Inflammatory Agents/administration & dosage , Anti-Inflammatory Agents/therapeutic use , Asthma/drug therapy , Body Height , Body Weight , Bronchodilator Agents/administration & dosage , Bronchodilator Agents/therapeutic use , Budesonide/administration & dosage , Budesonide/therapeutic use , Child , Female , Fluticasone , Humans , Male , Multivariate Analysis , Sex Factors , Ultrasonography
20.
Invest Radiol ; 37(8): 421-7, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12138357

ABSTRACT

OBJECTIVES: Different dielectric properties of cancerous tissues are correlated with increased conductance potentially measurable using Electrical Impedance Scanning (EIS). Sonographically based differentiation of lesions in the salivary glands remains difficult. The clinical value of EIS used additionally to Ultrasound was investigated. METHODS: Sonographically suspicious lesions of parotid (n = 25) and submandibular (n = 16) glands were examined using TransScan TS2000 (TransScan Medical, Israel; distributed by Siemens, Sweden). Bright focal spots representing areas of high conductance were read as positive; absence of a focal spot (ie, homogeneous gray) was read as negative. All lesions were histopathologically proved. RESULTS: 14/15 malignant (93.3%) and 13/26 benign lesions (50.0%) were correctly detected using EIS, NPV 93%, PPV 52%. All cases of squamous cell carcinoma were correctly identified. Lymph node relapse of T-cell lymphoma, lymph node relapse of malignant melanoma, malignant hemangioendothelioma and 2/3 adenocystic carcinoma (primary metastases) were correctly detected. CONCLUSIONS: Our initial results suggest EIS to be of interest when used adjunctively to ultrasound for the identification of malignant lesions of the salivary glands. However, low specificity induced in part by current technical restrictions (bone interference, skin alterations, contact artifacts, prominence of the lesions) limit this clinical application.


Subject(s)
Electric Impedance , Parotid Neoplasms/diagnostic imaging , Parotid Neoplasms/diagnosis , Submandibular Gland Neoplasms/diagnostic imaging , Submandibular Gland Neoplasms/diagnosis , Humans , Ultrasonography
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