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W A Kaiser

Publications and source records attributed to W A Kaiser.

At least 73 records · Page 4Linked to original sources
PubMed2001

[Cost-effectiveness of MR-imaging in the preoperative work-up of suspicious breast lesions].

UNLABELLED: Cost-effectiveness of MR-imaging in the preoperative work-up of suspicious breast lesions. PURPOSE: To assess the clinical and economic consequences of a preoperative magnetic resonance mammography (MRM) in patients with suspicious breast lesions. PATIENTS AND METHODS: 483 out of 2426 patients operated because of breast neoplasms at the University Hospital of Jena between August 1995 and March 1999 underwent preoperative Gd-enhanced breast MRI in addition to mammography and breast ultrasound because of suspicious breast lesions. The histological assessment was correlated with the results of the diagnostic imaging work-up in 447 cases. The costs of surgery for malignant lesions were calculated based on case- dependent billing agreements, costs of surgery of benign lesions were calculated based on current billing procedure. In 36 cases no surgery was performed due to the exclusion of malignancy by breast MRI. 140 benign lesions were treated surgically in spite of negative breast MRI diagnosis. The hospitalization time related costs caused by these cases were compared to the costs of preoperative MR-imaging. RESULTS: The total costs for MR mammography in all 483 patients amounted to DM 499,857. In 11 cases false positive results in MRM led to additional costs of DM 32,565. Assuming that there is no need for surgical treatment of benign breast lesions, total savings of DM 521,048 due to avoided hospitalization in 176 cases could have been possible. The savings per patient amount in these 176 cases are DM 2,960.50 compared to DM 1,034.90 costs for breast MRI. CONCLUSION: Despite the currently still high costs of breast MRI a major cost reduction can be achieved by prevention of unnecessary surgery, avoidance of additional surgery and associated trauma for patients.

Breast Neoplasms↗
PubMed2001

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.

Adipose Tissue↗
PubMed2001

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.

Alkenes↗
PubMed2001

Electromagnetic heating of breast tumors in interventional radiology: in vitro and in vivo studies in human cadavers and mice.

PURPOSE: To assess relevant parameters for the minimally invasive elimination of breast tumors by using a selective application of magnetite and exposure of the breast to an alternating magnetic field. MATERIALS AND METHODS: The specific absorption rate (SAR) of different magnetite samples was determined calorimetrically. Temperature elevations based on magnetite mass (7-112 mg) and magnetic field amplitude (1.2-6.5 kA/m frequency, 400 kHz) were investigated by using human breast tissue. Parameter combinations (21 mg +/- 9 [SD], 242-second magnetic field exposure, 6.5-kA/m amplitude) were tested in 10 immunodeficient mice bearing human adenocarcinomas (MX-1 cells). Histologic sections of heated tumor tissue were analyzed. RESULTS: SAR data of different magnetite particle types ranged from 3 to 211 W/g. Temperature elevation (DeltaT) as a function of the magnetite mass increased linearly up to 28 mg; at higher masses, a saturation of DeltaT was observed at nearly 88 degrees C. The dependence of DeltaT on magnetic field amplitude (H) revealed a third-order power law: DeltaT = 0.26 degrees C/(kA/m)(3). H(3), with r(2) = 0.95. A mean temperature of 71 degrees C +/- 8 was recorded in the tumor region at the end of magnetic field exposure of the mice. Typical macroscopic findings included tumor shrinkage after heating. Histologically nuclear degenerations were observed in heated malignant cells. CONCLUSION: Magnetic heating of breast tumors is a promising technique for future interventional radiologic treatments.

Animals↗
PubMed2001

Cerebral phosphate metabolism in first-degree relatives of patients with schizophrenia.

OBJECTIVE: Most phosphorus-31 magnetic resonance spectroscopy ((31)P-MRS) studies have described measures of lower membrane anabolism or greater catabolism in the frontal lobes of patients with schizophrenia. The purpose of the present study was to evaluate whether these findings can also be detected in young subjects at genetic risk for schizophrenia. METHOD: Fourteen children and siblings of patients with schizophrenia (mean age=16.7 years) and 14 comparison subjects (mean age=16.9 years) were included in a (31)P-MRS study of the frontal lobe. RESULTS: The high-risk subjects had significantly lower mean ratios of phosphomonoesters to phosphodiesters (0.25 versus 0.31) and higher mean phosphodiester values (37.59% versus 34.87%) than comparison subjects. CONCLUSIONS: These findings suggest greater phospholipid breakdown even in young first-degree relatives of patients with schizophrenia. This suggestion is discussed with respect to the membrane phospholipid hypothesis of schizophrenia.

Adolescent↗
PubMed2001

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.

Adult↗
PubMed2000

Hemodynamic assessment of acute stroke using dynamic single-slice computed tomographic perfusion imaging.

BACKGROUND: Stroke management would benefit from a broadly available imaging tool that detects perfusion deficits in patients with acute stroke. OBJECTIVE: To determine the role of dynamic, single-slice computed tomographic (CT) perfusion imaging (CTP) in the assessment of acute middle cerebral artery stroke. DESIGN AND PATIENTS: Imaging with CTP and CT within the first 6 hours of symptom onset and before the start of treatment in a consecutive clinical series of 22 patients (mean age, 68.3 years; 14 women; studied within 143 +/- 96 minutes of stroke onset). SETTING: A stroke unit in a university hospital. MAIN OUTCOME MEASURES: Area of the perfusion deficit (nAP(0)) from time-to-peak maps, hemispheric lesion area from follow-up CT (HLA(F)), final infarct volume, and stroke recovery (National Institutes of Health Stroke Scale scores). RESULTS: Eighteen patients had perfusion deficits in the middle cerebral artery territory and corresponding hypoattenuation in follow-up CT. Three patients with normal CTP findings showed lacunar infarctions or normal findings on follow-up CT. In 1 patient, CTP did not reveal a territorial deficit above the imaging slice. The overall sensitivity and specificity of CTP for the detection of perfusion deficits in patients with proven territorial infarction (n = 18) on follow-up CT were 95% and 100%, respectively. The nAP(0) was significantly correlated with the National Institutes of Health Stroke Scale score at admission (P<.003) and the HLA(F) (P<.001). Different stroke patterns were identified in patients with follow-up CTP (n = 10): (1) initial perfusion deficit and partial nutritional reperfusion (nAP(0)>HLA(F); n = 6), (2) initial perfusion deficit and nonnutritional reperfusion (nAP( 0)>/=HLA(F); n = 2), and (3) initial perfusion deficit without reperfusion (nAP(0)>/=HLA(F); n = 2). CONCLUSIONS: Computed tomographic perfusion imaging detects major perfusion deficits in the middle cerebral artery territory. Because CTP is broadly available, it may play a role in acute stroke management. Arch Neurol. 2000;57:1161-1166

Acute Disease↗
PubMed2000

Comparison of artifacts produced from carbon fiber and titanium alloy needles at 1.5 T MR imaging.

A novel coaxial carbon fiber-based biopsy needle set was investigated in phantom experiments and compared with a commercially available, magnetic resonance (MR)-compatible titanium alloy set using MR imaging at 1.5 T. Image artifacts observed with different MR sequences were assessed. It was found that the carbon fibers produced distinctly smaller image artifacts compared with the titanium needle. Depending on the type of MR sequence, the relative range of artifact size ratios between the carbon and titanium needles was between 0.7 (spin-echo sequence) and 0.4 (gradient-echo sequence) with the needles oriented perpendicular to the main magnetic field. Carbon fiber composites are promising materials for the design and construction of MR-compatible instruments.

Artifacts↗
PubMed2000

Ultrasound bone densitometry of the os calcis in children and adolescents.

The aim of the present investigation was to evaluate reference data and to examine whether there were weight-, height-, age-, and sex-related differences of the quantitative ultrasound bone parameters for healthy children and adolescents. A total of 3299 healthy Caucasian children and teenagers (1623 girls and 1676 boys), age range from 6-18 years (mean age 11.4 +/- 3.4 years for boys and mean age 11.5 +/- 3.3 years for girls) were examined by quantitative ultrasound densitometry (QUS) using the bone sonometer SAHARA (Hologic Inc., Waltham, MA, USA), a waterless, dry system. The parameters broadband ultrasound attenuation (BUA) [dB/MHz] and speed of sound (SOS) [m/second] were evaluated on the right heel in relation to age, sex, weight, and height. There is no correlation between the ultrasound bone parameter SOS and age, height, and weight. BUA increases with age, height, and weight. Significant differences in SOS and BUA between girls and boys were found to probably be caused by the different onset of growth phases and the onset of puberty. SOS and BUA are influenced by changes of bone mineral density. But BUA is dependent on bone size, too. In conclusion, ultrasound bone densitometry is a useful measuring method showing the physiological bone development in childhood and adolescence. The presented results can be used as reference data. Further studies in children with disorders influencing bone metabolism will show in what way various patterns of osteopenia in childhood can be detected.

Adolescent↗
PubMed2000

Electrical impedance scanning for classifying suspicious breast lesions: first results.

It has long been established that cancer cells exhibit altered local dielectric properties compared with normal cells. Consequently, different electrical conductivity and capacitance are measurable in malignant vs normal tissues. In this study we evaluated the reliability of electrical impedance scanning (EIS), a new technology, for the classification of suspicious lesions: differentiating benign from malignant, and as a primary means of detection of breast cancer. Fifty-two women with 58 sonographically and/or mammographically suspicious findings were examined using electrical impedance scanning. Two different examination modes of TransScan TS2000 (Siemens, Erlangen, Germany), the standard-resolution mode for a routine overview examination, and the targeted high-resolution mode for a local examination of the suspicious lesion were used. All patients were additionally imaged by MR mammography (MRM) and underwent core-biopsy and/or surgical treatment after the EIS examination. With respect to the histopathological findings (29 malignant and 29 benign lesions) 27 of 29 (93.1%) malignant lesions were correctly identified using the high-resolution mode of EIS, whereas 19 of 29 (65.5%) benign lesions were correctly identified as benign (10 of 29 benign lesions showed as false-positive findings). Negative and positive predictive values of 90.5 and 73.0% were observed, respectively. Using the standard-resolution mode 22 of 29 malignancies were correctly detected (sensitivity 75.9%), whereas 22 of 29 were correctly identified as benign (specificity 72.4%). Electrical impedance scanning appears to be a promising new technology providing a relatively high sensitivity for the verification of suspicious mammographic and/or sonographic lesions especially using the high-resolution mode for local examinations. Artifacts, such as signals from superficial skin lesions, poor contact, and air bubbles, are currently a limitation.

Breast Neoplasms↗
PubMed2000

Imaging in ureteral complications of renal transplantation: value of static fluid MR urography.

Ureteral obstruction is an infrequent complication after renal transplantation that may cause rapid loss of transplant function. We tested static fluid MR urography for determining the cause of graft hydronephrosis. Magnetic resonance urography was performed in nine transplants with dilated collecting systems on ultrasound. A heavily T2-weighted 3D turbo spin-echo sequence on a 1.5-T scanner was used and maximum intensity projections were obtained. The patients also underwent excretory urography (n = 1), renal scintigraphy (n = 1), antegrade pyelography (n = 3), voiding cystourethrography (n = 4), and non-enhanced CT (n = 2). Six patients had pathologic conditions including ureteral stricture, compression by lymphoceles, implantation stenosis, vesicoureteral reflux, and late-occurring transitional cell carcinoma at the implantation site. Static MRU was able to diagnose or exclude a dilation of the graft collecting system. It visualized the course of the ureters and localized the obstruction site in four of five obstructed transplants. In one case the ureter was obscured by lymphoceles, which were demonstrated by hydrographic MRU as well. The definite cause for obstruction was provided in only 2 of 5 cases. Dilation due to vesicoureteral reflux could not be differentiated. The current multimodality approach to renal transplant imaging already provides comprehensive assessment of graft hydronephrosis. Static MRU may be useful in some cases since complications associated with intravenous iodinated contrast or antegrade pyelography can be avoided. Its main drawback, the lack of functional information, may be overcome by combining it with contrast-enhanced MRU.

Adult↗
PubMed2000

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.

Breast Neoplasms↗
PubMed2000

[Reduction of radiation dosage by using digital luminescence radiography on a hand phantom].

PURPOSE: How much can the radiation dose be reduced for hand radiography by using digital luminescence radiography (DLR)? METHODS AND MATERIALS: A hand phantom (3M) with a cyst, two fractures and an "amputation" was digitally exposed in an anterior-posterior orientation using DLR (ADC-70, Agfa). The tube current time product (mAs) was reduced gradually while keeping the voltage constant. The surface entrance dose was measured by a Dosimax sensor (Wellhöfer). Five investigators evaluated the images for characteristics and critical features, pathological findings, visual resolution and contrast. RESULTS: The surface entrance dose at 50 kV/5 mAs was 31 microGy. The images could be evaluated very well down to an average dose of 36% (11 microGy); sufficient images were obtained down to an average dose of 26% (8 microGy). The resolution of the line pairs was the same or reduced by 1 level depending on the investigator. Contrast was assessed as being very good to sufficient. CONCLUSION: For the sufficient exclusion of a fracture the dose can be reduced to at least 39%, for the sufficient assessment of bony union and possible inflammatory changes to at least 42%, to position check and foreign body search to at least 23%. By DLR the following question-referred mAs-product at 50 kV are stated: fracture exclusion 2 mAs, bony union, arthritis and osteomyelitis 2.2 mAs, position check and foreign body search 1.25 mAs.

Foreign Bodies↗
PubMed2000

31P magnetic resonance spectroscopy in fibromyalgic muscle.

OBJECTIVE: To measure inorganic phosphate (Pi), phosphocreatine (PCr), ATP and phosphodiesters (PDE) in fibromyalgic muscle tissue by (31)P magnetic resonance spectroscopy. METHODS: A 1.5 Tesla scanner with a P 100 surface coil was used to examine 15 patients (mean age 49.9+/-14.3 yr) with fibromyalgia, according to the American College of Rheumatology criteria, and 17 healthy controls (mean age 30.2+/-5.8 yr). RESULTS: Compared with the controls, there were increases in the levels of PDE (+22%, P = 0.032) and Pi (+19%, P = 0.019) in the spectra of fibromyalgia patients, but there was no difference in pH. CONCLUSION: The metabolic differences we found may have been related to weakness and fatigue in the fibromyalgia patients, but they do not fully explain the fibromyalgia symptoms.

Adenosine Triphosphate↗
PubMed2000

Saline-enhanced radiofrequency ablation of breast tissue: an in vitro feasibility study.

RATIONALE AND OBJECTIVES: The feasibility of radiofrequency (RF) ablation for the treatment of breast tumors was investigated in vitro. The best parameters for ablation of breast tissue were chosen. METHODS: Saline-enhanced RF ablation was performed in human breast tissue specimens and cow udder tissue. Temperature profiles were measured depending on RF power (20, 28, 36 W) and NaCl infusion rate (15, 30, 60 mL/h) using eight thermocouples. Lesion development was monitored by ultrasound. Thermolysis efficiency was measured by tissue weight determinations before and after ablation. RESULTS: After RF ablation of tissue samples, 73.6% turned into a fat/saline emulsion. Ultrasound monitoring showed a cone-shaped hyperechoic area during the first 2 minutes of RF ablation, followed by an irregular expansion of the area. Time-dependent spatial temperature curves were more homogeneous at low infusion rates (15 mL/h). Peak temperatures up to 160 degrees C were measured. CONCLUSIONS: Controlled RF ablation of breast tissue is feasible. The irregular expansion of RF lesions in fatty breast tissue is due to liquefied fat. Low saline interstitial infusion rates result in better control of lesioning.

Animals↗
PubMed2000

Effects of magnetic thermoablation in muscle tissue using iron oxide particles: an in vitro study.

RATIONALE AND OBJECTIVES: To study the effects of magnetic thermoablation in muscle tissue from cow to assess interrelations that might be relevant for a minimally invasive therapy system in the long term. METHODS: Magnetite particles (50-180 mg) were placed in muscle tissue. Temperature elevations as a function of time and distance from the center of the magnetite deposition area were measured during the exposure (up to 304 seconds) to an alternating magnetic field (frequency 400 kHz, amplitude 6.5 kA/m) generated by a circular coil (diameter 90 mm). Measured curves were reproduced by numerical calculations. Tissue alterations, macroscopically visible as light-brown discoloration, were recorded by volume estimations and histopathologic studies. RESULTS: Significant temperature elevations (up to 87 degrees C) were reported within a distance of less than 15 mm from the magnetite deposition area. High initial heating rates were observed during the first 150 seconds of heating. The reproduction of the measured curves by numerical calculations was good (SD = 0.7 degrees C). The theoretical simulation was verified and applied to situations beyond the range of experimental conditions. Damaged tissue comprised pyknotic cell nuclei and degenerated myofibrils. Corresponding volumes were found to be up to 10 times higher than the volume of iron oxide dispersion. CONCLUSIONS: The data demonstrate the applicability of local magnetic thermoablation for therapy of muscle lesions in the long term.

Animals↗
PubMed2000

First experiences in using a new ultrasound mode and ultrasound contrast agent in the diagnosis of blunt renal trauma: a feasibility study in an animal model.

RATIONALE AND OBJECTIVES: To evaluate the diagnostic value of the new ultrasound mode "wide-band harmonic" (WBH) using an ultrasound contrast agent in blunt renal trauma in an animal model. METHODS: A defined blunt renal trauma was induced in 10 rabbits according to published standards. Ultrasound (B-mode, color and power Doppler, WBH) was performed before and after trauma, with and without using a contrast agent (Levovist). Ultrasound features were compared with histologic findings. RESULTS: In 2 of the 10 rabbits, three focal renal intraparenchymal lesions with diameters ranging from 1.0 to 1.8 mm were found that could be identified only using WBH with contrast. Six of the 10 rabbits developed a subcapsular hematoma with a thickness of up to 1.5 mm, which was identified by conventional B-mode as well as WBH. Histologic workup confirmed these findings of intraparenchymal hematomas and did not reveal further lesions. CONCLUSIONS: Only 20% of the experimental subjects developed parenchymal lesions with diameters of 1.0 mm or larger. All these lesions were identified only using WBH. These results indicate the potential to use WBH plus contrast for the diagnosis of blunt renal trauma.

Animals↗