[Computer-assisted diagnostic procedure for multislice computed tomography for assessment of the pulmonary arterial circulation. Clinical relevance]. / Computerassistiertes Diagnoseverfahren für die Mehrschichtcomputertomographie zur Beurteilung der pulmonalarteriellen Strombahn. Klinische Bedeutung.

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.

Whole-body MRI: a powerful alternative to bone scan for bone marrow staging without radiation and gadolinium enhancer.

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.

[Is the application of CAD useful for radiologists for passing the official tests required for outpatient breast imaging?]. / Inwieweit verbessert der Einsatz eines CAD-Systems das Prüfungsergebnis bei der Beurteilung einer kassenärztlichen Mammographiefallsammlung?

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.

[The effect of sports activities in children and adolescents on the calcaneus--an investigation with quantitative ultrasound]. / Einfluss sportlicher Aktivität von Kindern und Jugendlichen auf den Kalkaneus -- Eine Untersuchung mit quantitativem Ultraschall.

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.

[Influence of body constitution on bone mineral density measured by digital radiogrammetry]. / Einfluss der Körperkonstitution auf die mittels digitaler Radiogrammetrie evaluierte Knochenmineraldichte.

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.

Additional value of electrical impedance scanning: experience of 240 histologically-proven breast lesions.

The aim of this study was to quantify the clinical value of using electrical impedance scanning (EIS) as an adjunct to other diagnostic techniques in order to identify cancerous tissue based upon its inherent altered local dielectric properties. 210 consecutive women with 240 sonographically and/or mammographically suspicious findings were examined using EIS. All lesions were histologically-proven. 86/103 malignant and 91/137 benign lesions were correctly identified using EIS (87.8% sensitivity, 66.4% specificity). NPV and PPV of 84.3% and 65.2% were observed, respectively. Excluding cases as defined by a priori criteria, i.e. lesions located deeper than 35 mm, lesions larger than 35 mm, and retroareolar lesions, a sensitivity of 85.5% was observed, and for invasive cancers, 91.7%. The detection rate for ductal carcinoma in situ (DCIS) was poor (57.1%, n=14). By adding EIS to mammography and ultrasound, the sensitivity rose from 86.4 to 95.1%, whereas the accuracy decreased from 82.3 to 75.7%. EIS appears to be of interest as an adjunct to breast diagnostic techniques, performing with a reasonable sensitivity. Further investigations on histomorphological characteristics and the reasons for false-negative findings are essential to gain further knowledge about the bioelectricity of breast lesions, and prove the value of this new technology.

Contrast-enhanced near-infrared laser mammography with a prototype breast scanner: feasibility study with tissue phantoms and preliminary results of imaging experimental tumors.

RATIONALE AND OBJECTIVES: Near-infrared (NIR) optical mammography without contrast has a low specificity. The application of optical contrast medium may improve the performance. The concentration-dependent detectability of a new NIR contrast medium was determined with a prototype optical breast scanner. In vivo imaging of experimental tumors was performed. METHODS: The NIR contrast agent NIR96010 is a newly synthesized, hydrophilic contrast agent for NIR mammography. A concentration-dependent contrast resolution was determined for tissue phantoms consisting of whole milk powder and gelatin. A central part of the phantoms measuring 2 x 2 cm2 without contrast was replaced with phantom material containing 1 micromol/L to 25 nmol/L NIR96010. The composite phantoms were measured with a prototype NIR breast scanner with lasers of lambda1 = 785 nm and lambda2 = 850 nm wavelength. Intensity profiles and standard deviations of the transmission signal in areas with and without contrast were determined by linear fit procedures. Signal-to-noise ratios and spatial resolution as a function of contrast concentration were determined. Near-infrared imaging of five tumor-bearing SCID mice (MX1 breast adenocarcinoma, tumor diameter 5-10 mm) was performed before and after intravenous application of 2 micromol/kg NIR96010. RESULTS: Spectrometry showed an absorption maximum of the contrast agent at 755 nm. No spectral shifts occurred in protein-containing solution. Signal-to-noise ratio in the transmission intensity profiles ranged from 1.1 at 25 nmol/L contrast to 28 at 1 micromol/L. At concentrations <40 nmol/L, no differentiation from the background was possible. The transitional area between the contrast-free edge of the phantom and the central contrast-containing part appeared in the profiles as a steep increase with a width of 4.2 +/- 1.8 mm. The experimental tumors were detectable in nonenhanced images as well as contrast-enhanced images, with better delineation after contrast administration. In postcontrast absorption profiles, a 44.1% +/- 11.3% greater absorption increase was seen in tumor tissue compared with normal tissue. CONCLUSIONS: The laser wavelength lambda1 of the prototype laser mammography device was not situated at maximum absorption of the contrast agent NIR96010 but on the descending shoulder of the absorption spectrum. This implies a 20% signal loss for contrast detection. Despite the nonideal measurement conditions, concentrations as low as 40 nmol/L were detectable in vitro. In vivo, all tumors were detectable in color-coded nonenhanced scans as well as in contrast-enhanced scans, with better delineation after contrast administration.

Percutaneous radiofrequency (RF) thermal ablation of rabbit tumors embedded in fat: a model for RF ablation of breast tumors.

RATIONALE AND OBJECTIVES: To develop an experimental tumor model for RF ablation of breast tumors surrounded by fat and to investigate the minimally invasive treatment of such tumors by saline-enhanced RF ablation monitored by ultrasound (US). METHODS: Twenty-eight VX2 tumors were implanted into the retroperitoneum of 14 rabbits and monitored by B-mode US at regular intervals of 2 to 3 days. Saline-enhanced RF ablation (25-mm tip length) was performed 16 days after tumor implantation (10-minute treatment time, 28 W, 15 mL/h infusion of 0.9% NaCl, which was increased to 30 mL/h in cases of an impedance increase). Thermal lesion growth was monitored by B-mode US. Treatment was considered complete if no relapse was detectable histopathologically after a follow-up period of up to 3 weeks. RESULTS: All tumor implantations were successful, reaching sizes from 5 to 38 mm 16 days after implantation. Tumors >20 mm showed central necrosis on US. Smaller tumors without signs of necrosis required greater needle perfusion to maintain constant needle-to-tissue impedance. Local relapses occurred in 14 of 27 tumors (51.8%), all with tumors >20 mm. In 12 cases, they were already detected sonographically. In 2 cases, "islands" of vital tumor were detected only during histopathological assessment. CONCLUSIONS: VX2 tumors are implantable into hypovascular adipose tissue with a high success rate and may be used as a model for RF ablation of breast tumors. B-mode US is not suitable for guiding RF ablation of tumors embedded in fat. The method appears to be more successful with smaller tumors.

Electrical impedance scanning used in addition to ultrasound for the verification of submandibular and parotid lesions: initial results.

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.

Electrical impedance scanning: a new technique in the diagnosis of lymph nodes in which malignancy is suspected on ultrasound.

Differentiation between inflammatory and malignant lymph nodes by ultrasound is difficult. Electrical impedance scanning (EIS) is a new diagnostic tool, so far used primarily for the identification of malignant breast lesions. Cancer cells have altered dielectric properties compared with normal cells, thereby distorting the local electrical field. The induced changes in capacitance and conductivity are measurable using EIS. We evaluated EIS in demonstrating the cause of lymph node enlargement. 51 lymph nodes that were suspicious for malignancy on ultrasound (32 patients, mean age 32 years), with a mean size of 18 mm x 12 mm x 10 mm, were examined. The following lymph node locations were included in the study: cervical, inframandibular, axillary, paraaortic and inguinal. EIS results were compared with histopathological and follow-up findings. 30/34 malignant lymph nodes were correctly detected using EIS, while 14/17 inflammatory or benign lymph nodes were correctly identified as benign by EIS; thus, there were 4/51 false negative and 3/51 false positive cases. The sensitivity was 88.2% and the specificity was 82.4%. Corresponding negative and positive predictive values were 77.8% and 90.9%, respectively. Results from this initial study suggest the potential usefulness of EIS as an adjunctive imaging modality in the differentiation of lymphadenopathy that is equivocal on ultrasound. The best accuracy was obtained in the cervical, axillary and inguinal regions. Owing to technical restrictions of the present system, examination of inframandibular and paraaortic lymph nodes should be limited to special cases.

Reproducibility--an important factor determining the quality of computer-aided detection (CAD) systems.

PURPOSE: To test the reproducibility of markings on mammography films set by a commercial computer aided detection (CAD) system. PATIENTS AND METHODS: One hundred unilateral mammography examinations (each in CC and MLO) of 100 patients with mammographically detected suspicious foci, which were histopathologically proven to be malignant, were scanned three times with the CAD system, retrospectively. Every fifth patient of the institutional tumor case sampler was enrolled in the study. Only cases with one visible lesion were included in the study. Reproducibility and sensitivity (in both the strict and the broader sense) were determined. Strict sensitivity means the correct set of markers in both images, whereas broader sensitivity means the correct set in at least one of the images. Sixteen of 100 malignancies were indicated by focal suspicious microcalcification clusters, 53 tumors by masses and 31 cases by both signs of breast cancer. The CAD evaluation was divided into only two different markers: one for microcalcifications and one for masses. Thus, 47 (16+31) tumor-induced microcalcifications and 84 (53+31) malignancy-related masses were checked using the CAD system. RESULTS: Eighteen of 100 unilateral mammography examinations revealed identical patterns in all three scans (18% reproducibility). Eleven of 47 suspicious focal microcalcification clusters and 43/84 masses were correctly marked on both mammographic views in all three CAD scans (strict and broader sensitivity, 23.4 and 51.1%, respectively). Six of 47 microcalcification clusters and 8/84 masses were totally missed in all images by the system (false negative rate, 12.8 and 9.6%, respectively). CONCLUSION: Reproducibility is essential for CAD systems. Currently, reproducibility of the used CAD system appears to be insufficient for clinical routine. Improvement of the system characteristics would make such systems valuable as a 'second reader' in clinical examination.

[Prospective analysis of quantification of contrast media enhanced power Doppler sonography of equivocal breast lesions]. / Computerassistierte Quantifizierungsanalyse der kontrastmittelverstärkten Powerdoppler-Sonographie bei unklaren Herdbefunden der Mamma.

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.

[Evaluation of the primary diagnosis with a CAD-system in mammography]. / Evaluation der Primärbefundung durch ein CAD-System in der Mammadiagnostik.

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.

[Early results of ultrasound based calculation of broadband ultrasound attenuation and speed of sound in children and adolescents suffering from asthma]. / Erste Ergebnisse der ultraschallbasierten Bestimmung der Schallabsorption und Schallgeschwindigkeit bei Kindern mit Asthma bronchiale.

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.

The impact of lesion vascularisation on tumours detection by electrical impedance scanning at 200 Hz.

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.

[Emergency treatment of thoracic trauma]. / Erstversorgung bei Thoraxtrauma.

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.

Peripheral bone status in rheumatoid arthritis evaluated by digital X-ray radiogrammetry and compared with multisite quantitative ultrasound.

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.

Multi-site quantitative ultrasound compared to dual energy X-ray absorptiometry in rheumatoid arthritis: effects of body mass index and inflamed soft tissue on reproducibility.

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.

Digital radiogrammetry as a new diagnostic tool for estimation of disease-related osteoporosis in rheumatoid arthritis compared with pQCT.

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

Digital X-ray radiogrammetry combined with semiautomated analysis of joint space widths as a new diagnostic approach in rheumatoid arthritis: a cross-sectional and longitudinal study.

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.