Search PubMed⌕ Search

Biomedical subjects

P Wunderbaldinger

Publications and source records attributed to P Wunderbaldinger.

At least 37 records · Page 2Linked to original sources
PubMed1999

Amplitude-coded color doppler: clinical applications.

Amplitude-coded color Doppler sonography (ACD) has become an useful adjunct to gray-scale US and conventional color Doppler sonography (CD) for the assessment of vascular diseases and pathologic conditions that might affect or alter tissue vascularization or perfusion. Basically, all US units that generate conventional color Doppler information through autocorrelation technique are capable of displaying ACD. This technique is also referred to as power Doppler, amplitude-mode color Doppler US, color Doppler energy (CDE), or US angiography. Amplitude-coded color Doppler sonography has already emerged as a valuable adjunct to conventional CD, particularly for evaluating flow in parts of the body where CD signal is weak because of slow flow, small blood vessels, or both.

Blood Flow Velocity↗
PubMed1999

World Wide Web and Internet: applications for radiologists.

Global exchange of information is one of the major sources of scientific progress in medicine. For management of the rapidly growing body of medical information, computers and their applications have become an indispensable scientific tool. Approximately 36 million computer users are part of a worldwide network called the Internet or "information highway" and have created a new infrastructure to promote rapid and efficient access to medical, and thus also to radiological, information. With the establishment of the World Wide Web (WWW) by a consortium of computer users who used a standardized, nonproprietary syntax termed HyperText Markup Language (HTML) for composing documents, it has become possible to provide interactive multimedia presentations to a wide audience. The extensive use of images in radiology makes education, worldwide consultation (review) and scientific presentation via the Internet a major beneficiary of this technical development. This is possible, since both information (text) as well as medical images can be transported via the Internet. Presently, the Internet offers an extensive database for radiologists. Since many radiologists and physicians have to be considered "Internet novices" and, hence, cannot yet avail themselves of the broad spectrum of the Internet, the aim of this article is to present a general introduction to the WWW/Internet and its applications for radiologists. All Internet sites mentioned in this article can be found at the following Internet address: http://www.univie.ac. at/radio/radio.html (Department of Radiology, University of Vienna)

Humans↗
PubMed1999

Thoracic venous anatomy delineated by malpositioned central venous catheters on plain chest films.

The aim of this essay was to demonstrate the thoracic venous anatomy as delineated by malpositioned central venous catheters on plain chest radiographs. We therefore used the didactic advantage of clinically inadvertent catheter positions. This approach was chosen to illustrate venous anatomy with plain chest radiographs, and, thereby, to recognize malpositions promptly on the modality with which positions of central venous catheters is routinely performed.

Catheterization, Central Venous↗
PubMed1999

Cystic fibrosis: CT assessment of lung involvement in children and adults.

PURPOSE: To compare a computed tomographic (CT)-based scoring system with nonimaging indexes of pulmonary status in patients with cystic fibrosis. MATERIALS AND METHODS: Pulmonary CT findings were assessed in 117 patients with cystic fibrosis, with cases classified according to three groups by age; 0-5 years, 6-16 years, and 17 years and older. Images were examined for specific abnormalities, and the severity and anatomic extent of each sign were used to generate a score. Scores in each category and the global score for each patient were correlated with pulmonary function test results, clinical status, serum immunoglobulin levels, and genotype, all obtained within 2 weeks of CT. RESULTS: The most frequent individual CT abnormalities were bronchiectasis in 94 (80.3%), peribronchial wall thickening in 89 (76.1%), mosaic perfusion in 71 (63.9%), and mucous plugging in 56 (51.3%) patients. The percentage of patients with specific CT findings and the overall CT scores increased significantly (P < .05) with progressively increasing age groups. All CT findings and the overall CT scores correlated significantly (P < .05) with the pulmonary function test results, serum immunoglobulin levels, and clinical scores. No relationship was observed between genotype and CT scores. CONCLUSION: Scoring of CT studies in patients with cystic fibrosis seems to offer a reliable way to monitor disease status and progression and may provide a reasonable tool to assess treatment interventions.

Adolescent↗
PubMed1999

Evolution of CT findings in patients with cystic fibrosis.

OBJECTIVE: The aim of our study was to assess the evolution of pulmonary CT findings in cystic fibrosis patients. MATERIALS AND METHODS: Serial CT examinations were performed in four different follow-up periods on 107 patients with cystic fibrosis. Lung images of the initial and follow-up CT were reviewed and scored for specific morphologic findings. CT findings were correlated with the results of the pulmonary function tests and clinical (Shwachman-Kulczycki) scores. RESULTS: Morphologic changes were minor within the first 18 months of follow-up compared with the period after 18 months. The increase of the overall score was significantly higher in groups with follow-up periods longer than 18 months compared with groups with follow-up periods shorter than 18 months. Various components of morphologic changes contributed to the sequential changes seen on the CT scans. All morphologic changes and the CT scores correlated significantly (p < .0001) with pulmonary function tests and clinical score. CONCLUSION. Serial CT scans allow assessment of the evolution of pulmonary abnormalities in patients with cystic fibrosis. CT seems to have advantages over pulmonary function tests and clinical scoring in the depiction of pulmonary changes over time.

Adolescent↗
PubMed1998

[Trauma of the facial bones and skull].

Facial trauma is frequent and mainly caused by motor vehicle accidents. Due to this main etiologic factor, trauma to the facial skeleton is often associated with serious injuries, commonly involving the brain, chest or abdomen. As a consequence, the initial clinical management of these patients includes control of hemorrhage and immediate assessment of life-threatening injuries, including the maintenance of the airways. Patients presenting with facial trauma are initially evaluated with a systematic clinical examination because many fractures can be accurately diagnosed by inspection and palpation alone. In these cases plain film radiographs serve only for confirmation and documentation of the diagnosis. In many other cases accompanying and extensive soft tissue swelling may clinically obscure fractures. A complete and accurate evaluation of these patients requires additional radiological imaging methods. A series of plain films may be generally sufficient but in most of the cases they can be regarded as initial screening methods for more thorough diagnosis with computed tomography (CT). In trauma patients CT is the imaging method of choice because it shows more fracture lines and displaced fragments than any other imaging modality. CT delineates soft tissue and bony structures and can localize and even characterize foreign bodies. A complete and accurate characterization of the fracture type and potentially associated complications in mandatory for the appropriate treatment and can only be achieved by careful radiological (CT) evaluation.

Craniocerebral Trauma↗
PubMed1998

New-born infants with severe hyaline membrane disease: radiological evaluation during high frequency oscillatory versus conventional ventilation.

OBJECTIVE: The aim of our study was to determine the impact of treatment with exogenous surfactant (ES) and high frequency oscillatory ventilation (HFOV) on the radiological appearance and clinical course of hyaline membrane disease (HMD) in new-born infants. MATERIALS AND METHODS: New-born infants (18) (median weight, 1010 g) with severe HMD (stages 3.5 and 4) who were treated with ES and HFOV were matched by birth weight and severity of disease with 18 new-born infants treated with ES and conventional mechanical ventilation (CV). Chest radiograms taken on days 1, 2/3, 4/5, 7, 14 and 28 were analyzed to check for the severity of generalized parenchymal opacities (GPO), local opacifications, pulmonary interstitial emphysema (PIE), gross air leak, general and localized overinflation, bronchopulmonary dysplasia (BPD) and clinical variables such as survival rates, duration of mechanical ventilation, mean airway pressure and inspired oxygen concentration. RESULTS: At 4 weeks of age, new-born infants treated by HFOV had less severe GPO (median degree 1.5 vs. 3), less PIE (1 vs. 7 patients) and fewer signs of BPD (median BPD degree 1.5 vs. 2.6). The incidence of pneumothorax and of local opacifications were similar in both groups. New-born infants on HFOV had a lower mortality rate (5 vs. 13), needed fewer days of mechanical ventilation (median 15 vs. 23 days) and lower inspiratory oxygen concentrations (median FiO2 0.38 vs. 0.64). CONCLUSION: In new-born infants with HMD, treatment with ES and HFOV resulted in a favourable radiological and clinical outcome as compared to treatment with ES and CV.

Bronchopulmonary Dysplasia↗
PubMed1998

Double inversion recovery imaging of the brain: initial experience and comparison with fluid attenuated inversion recovery imaging.

The purpose of this study was to evaluate the diagnostic efficacy of the double inversion recovery fast spin echo (DIR-FSE) sequence for brain imaging compared to the fluid-attenuated inversion recovery (FLAIR) sequence. DIR-FSE and FLAIR-FSE sequences were obtained and compared side by side. Image assessment criteria included lesion conspicuity, contrast between different types of normal tissue, image quality, and artifacts. In addition, contrast ratios and contrast-to-noise ratios were determined. Scan time of DIR-FSE was 33% longer than scan time of FLAIR-FSE. Overall lesion conspicuity was equal on DIR-FSE and FLAIR-FSE; however, DIR-FSE showed particular advantages for infratentorial lesions and lesions with only poor contrast on T2-weighted images, whereas FLAIR was slightly superior for small superficial cerebral abnormalities. Gray-white differentiation was better with DIR-FSE. Cerebrospinal fluid suppression was equal on both sequences; cerebrospinal fluid pulsation artifacts were more pronounced on DIR-FSE but did not cause diagnostic difficulties on these images. We conclude that DIR-FSE might be obtained if infratentorial lesions and abnormalities with only slightly prolonged T2 relaxation times are suspected. Otherwise, FLAIR-FSE seems preferable.

Adolescent↗
PubMed1998

Evaluation of needle size for breast biopsy: comparison of 14-, 16-, and 18-gauge biopsy needles.

OBJECTIVE: The purpose of our study was to compare the quantity and quality of tissue harvested from breast biopsy when using 14-, 16-, and 18-gauge "long-throw" needles. SUBJECTS AND METHODS: We performed a prospective randomized study in 64 patients with 66 breast lesions. Under stereotactic guidance, passes were made in random order with each of the three biopsy needles in each lesion. Samples were measured for tissue area and scored for their quality. All lesions, including benign and malignant lesions and lesions with and without microcalcifications, were analyzed. Findings of the biopsy samples were compared with the final diagnoses made at surgical excision. RESULTS: In all 66 lesions, 14-gauge biopsy needles obtained significantly larger specimens (14-gauge, 13.14 mm2; 16-gauge, 9.6 mm2; 18-gauge, 6.41 mm2; p < .05) and scored significantly better (14-gauge, 8.37; 16-gauge, 7.56; 18-gauge, 7.14; p < .016) than either of the smaller needles. The results for malignant and benign lesions and for lesions with and without microcalcifications were similar but not equal to the overall results. However, benign lesions and areas with microcalcifications seem to be more problematic for both smaller needles than for 14-gauge needles. CONCLUSION: Our results indicate that the quantity and quality of breast biopsy specimens depend on the needle size. Of the three needle sizes tested, only 14-gauge long-throw biopsy needles can be recommended for breast biopsy.

Biopsy, Needle↗
PubMed1998

[Computer-assisted diagnosis in mammography: the R2 ImageChecker System in detection of spiculated lesions].

Because of the rapid development of computer systems for digitalization and image analysis, they play an increasing important role in computer-assisted diagnosis (CAD). Especially in the field of mammography, the early signs of malignancy are relatively uniform and therefore more easily detected by a computer algorithm. In this study, we tested one of the few commercially available systems for the detection of both microcalcifications and suspicious, spiculated solid lesions on 40 cases of proven breast carcinomas. These mammograms were analyzed by three independent observers with and without knowledge of the computer results, respectively. Depending on the time of their radiologic experience, the sensitivity of the observers alone was 92.4%, 86.1% and 82%. With knowledge of the computer interpretation, sensitivity of all three observers rose significantly to 100%, 92.7%, and 95%, respectively. However, due to a high number of false positive results of the computer algorithm (0.4 markers per image), the positive predictive value of the interpretations worsened from 100%, 92.7%, and 95.5% to 86.4%, 97.3%, and 91.1%, respectively. It can be expected that future developments will soon overcome this problem and CAD will become an effective tool in screening mammography.

Adult↗
PubMed1998

[Ultrasound-controlled stereotactic breast biopsy--description and initial clinical results of a new breast biopsy device].

UNLABELLED: The aim of this prospective study was first to describe a new dedicated 3D-ultrasound guided stereotaxic breast biopsy unit and second its specificity, sensitivity, accuracy and positive predictive value (concerning malignant and benign lesions). Technical considerations are noted and discussed. SUBJECTS AND METHODS: 45 women (aged between 20 and 77 years; mean age: 49.73 years) with sonographically suspect breast lesions were assigned to the new biopsy device (Sonopsy, NeoVision Corporation, Seattle). All biopsies were performed by an experienced radiologists (G. Wolf) and the results compared to the surgical biopsies. RESULTS: Sensitivity and accuracy was 93.3%, specificity 100%, the positive predictive value (concerning malignant lesions) 95.4% and (concerning benign lesions) 97.8%. In 9/45 biopsies (20%) complications were noted (1 hematoma, 2 collapses, 5 vasovagale reactions). In 13/45 Cases (28.9%) the suspect lesions were more distinctively, respectively more clearly defined on the conventional/dedicated sonography unit. CONCLUSION: This dedicated unit combines all advantages of sonographic and stereotaxic guided core biopsies. Our results show that this technique is a promising new method for breast biopsy.

Adult↗
PubMed1997

[Sitting or supine stereotaxic core biopsy of the breast? A comparison based on a randomized, prospective study].

UNLABELLED: OBJECTIVE/MATERIAL AND METHODS: In a prospective randomized study, the techniques of stereotactic breast biopsies in prone and sitting position were compared. Part of the data has already been published. A total of 103 women underwent stereotactic breast biopsies, either prone (n = 51; using TRC-Mammotest, Sweden) or in the sitting position (n = 52; using Stereotix 2, General Electric Medical Systems, Milwaukee, Wisconsin, USA). With the help of pre- and post-biopsy questionnaires, anxiety, pain, and subjective experience were recorded in all patients. Vasovagal reactions were scored from 0 to 2 according to their severity. All biopsy results were verified by surgery. The specificities and sensitivities for the two positions were calculated and statistically compared. RESULTS: With regard to overall tolerance no statistically significant difference between biopsies performed in the sitting or the prone position was noted. Significantly more patients (p = 0.04) in the prone position stated they would prefer premedication prior to a repeat biopsy. Three patients (prone; n = 1; sitting; n = 2) fainted during the procedure. There was no statistically significant difference between the two biopsy positions regarding sensitivity (95%) and specificity (100%). CONCLUSIONS: More attention should be paid to patient care and, especially, preintervention information. Biopsies in the prone or sitting position are equally well tolerated. Somatic reactions are not a major problem during breast biopsy. Success and validity are independent of the biopsy position.

Adult↗
PubMed1997

[Temporal bone trauma and imaging].

Fractures of the temporal bone result from direct trauma to the temporal bone or occur as one component of a severe craniocerebral injury. Complications of temporal trauma are hemotympanon, facial nerve paralysis, conductive or sensorineur hearing loss, and leakage of cerebrospinal fluid. Early recognition and an appropriate therapy may improve or prevent permanent deficits related to such complications. Only 20-30% of temporal bone fractures can be visualized by plain films (7). CT has displaced plain radiography in the investigation of the otological trauma because subtle bony details are best evaluated by CT which even can be reformatted in multiple projections, regardless of the original plane of scanning. Associated epidural, subdural, and intracerebral hemorrhagic lesions are better defined by MRI.

Ear↗
PubMed1997

Sonomorphology of the gallbladder in critically ill patients. Value of a scoring system and follow-up examinations.

PURPOSE: The aim of the study was to assess the value of a scoring system for the diagnosis of acalculous cholecystitis (AC) on ultrasound (US) follow-up examinations and to discuss the merits of scoring system compared to clinical outcome and pathohistologic findings. MATERIAL AND METHODS: In this prospective study, 21 patients at the intensive care unit (ICU) of a medical department were examined by follow-up US. Sonographic parameters of the gallbladder (GB) were obtained (longitudinal and transversal diameter, wall thickening, contents, and pericholecystic fluid) and scored (2 points: distension of GB, thickening of GB wall; 1 point: striated thickening of GB wall, sludge, and pericholecystic fluid; range (0-8). The US findings were correlated with clinical findings and histology at cholecystectomy or autopsy. RESULTS: Of a total of 77 follow-up examinations in these 21 patients, US demonstrated GB distension in 19 patients, wall thickening in 18, sludge in 15, striated thickening of the GB wall in 13, and pericholecystic fluid in 12 patients. Of these, 41 (53%) examinations were scored > or = 6, and 36 (47%) examinations < or = 5. None of the patients with a maximum score during follow-up of < or = 5 (n = 8) had pathohistologic proof of AC or died due to GB complications. Patients with maximum scores of > or = 6: had pathohistologic proof of AC (n = 4); survived with normalization of GB morphology (n = 4); had a normal GB at autopsy (n = 1); or were lost for pathohistologic proof at autopsy (n = 2). CONCLUSION: Our results indicate that regular, short-term follow-up allows early diagnosis and immediate therapy for AC. The scoring system could be helpful in differentiating between patients with an abnormal GB without AC (score < or = 5) and those with an abnormal GB (score > or = 6) with a suspicion of AC. In the latter group, more aggressive diagnostic and therapeutic procedures may be indicated.

Adolescent↗
PubMed1997

Influence of osteophytic size on bone mineral density measured by dual X-ray absorptiometry.

PURPOSE: To quantify the relationship between individual osteophytic size and measured bone mineral density (BMD) of the lumbar spine by dual x-ray absorptiometry (DXA). Further, to evaluate the possible consequences of this relationship for the management of DXA measurements in postmenopausal patients. MATERIAL AND METHODS: In 142 postmenopausal women (mean age 61.8 +/- 8.9 years), plain radiographs of the lumbar spine were evaluated and graded according to evidence and size of osteophytes. The BMD (g/cm2) and Z-score (deviation of BMD from an age-matched population, %) of each vertebral body was determined by DXA. The effects of the individual osteophytic size on BMD measurements were analyzed by using analysis of variance followed by a multiple test procedure. RESULTS: The presence of osteophytes resulted in a significant increase in BMD of L1 through L4. The increase in relation to an osteophytic size of about 10 mm was: in L1 5.7%, in L2 6.8%, in L3 4.4% and in L4 3.5%. Increases were significantly higher for an osteophytic size of 10-20 mm (L1 23.1%, L2 13.0%, L3 13.4%, and L4 16.3%) and of > 20 mm (L1 21.4%, L2 22.4%, L3 21.1% and L4 4.1%). CONCLUSION: Our results indicate a nonlinear increase of measured BMD with increasing osteophytic size. These effects should be considered in routine examination and patient management.

Absorptiometry, Photon↗