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K Turetschek

Publications and source records attributed to K Turetschek.

At least 55 records · Page 3Linked to original sources
PubMed1998

[Treatment of arterial aneurysms of the pelvic leg vessels using dacron covered nitinol stents].

PURPOSE: To evaluate the success rates of the implantation of stent grafts in the treatment of peripheral aneurysms. MATERIALS AND METHODS: In 13 patients with 15 aneurysms at the common iliac artery (n = 6), external iliac artery (n = 1), hypogastric artery (n = 2), femoral artery (n = 2) or popliteal artery (n = 4), implantation of dacron-covered nitinol stents was performed. The patients were followed up for three to 20 months (mean, 8.8 months) with intravenous digital subtraction angiography, CT or colour-coded Doppler sonography. RESULTS: In all cases, the aneurysm was successfully occluded after stent implantation. In one case with a popliteal aneurysm, kinking of the vessel caused thrombosis of the stent. The stent was successfully reopened. The aneurysm however, had to be surgically treated 9 months later. The primary and secondary patency rates at 6 months were 93% and 100%, respectively. CONCLUSION: The method described might be an alternative therapy to surgery. There are some limitations in respect of treatment of popliteal aneurysms.

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

[Diagnostic imaging after liver transplantation].

INTRODUCTION: Orthotopic liver transplantation (OLT) has become an accepted treatment for end-stage liver disease. However, postoperative complications result in significant patient morbidity and mortality. Early detection and treatment of these complications is therefore of utmost importance. MATERIALS AND METHODS: We retrospectively reviewed the postoperative complications of the patients who underwent OLT at our institution. Duplex Doppler sonography and cholangiography were the primary imaging modalities in postoperative evaluation of the transplanted liver. Other important techniques were CT, MRI and angiography, which may contribute to a reliable diagnosis of vascular or biliary complications. RESULTS: Second to primary organ dysfunction, vascular complications are the most frequent cause of graft loss. Thrombosis of the hepatic artery is the most common and most serious vascular complication, with a reported incidence from 4 to 42%. Bile duct sludge, leaks and strictures are frequent complications after liver transplantation, which can contribute to graft dysfunction. Biliary tract complications usually occur within the first 3 months and require interventional radiological or surgical therapy. Since liver transplant recipients undergo immunosuppressive therapy, they are at increased risk of developing late post-transplant malignancies, which are best depicted by US, CT or MRI. However, radiological diagnosis of lympho-proliferative disorder has to be confirmed by liver biopsy. CONCLUSION: Cholangiography and Duplex sonography are routinely used in the postoperative evaluation of patients with OLT. CT, MRI, and angiography are problem-solving tools in equivocal cases.

Diagnostic Imaging↗
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

[MRI on low-field tomography systems (0.2 Tesla). A quantitative comparison with equipment of medium-field strength (1.0 Tesla)].

AIM OF THE STUDY: Using phantom studies, a dedicated low-field MR system with 0.2 T and a whole-body MR-scanner with 1.0 T were compared. METHODS: A spin-echo sequence was performed on the 0.2-T MR unit using the knee coil and on the 1.0-T MR unit with the head coil. In a water-filled phantom, signal-to-noise ratios (SNR) were calculated and contrast measurements on gels with well-defined relaxation times were obtained and compared to nominal relaxation times. Measurements of T1 and T2 relaxation times on the low-field system were compared to the 1.0-T unit. As a parameter for geometrical image quality, magnetic field distortions were calculated. In theory, influence of field strength and and receiver bandwidth on the minimal echo time and on chemical shift artifacts were calculated. RESULTS: The SNR was 63.2 on the 0.2-T and 179.6 on the 1.0-T MR unit (difference factor 3, against a theoretical difference of 5-16). Relaxation times on the low-field system were significantly (around 40-50%) lower. Measurements of contrast were similar on both systems. On the low-field system geometrical distortions of several pixels were recorded. The minimal echo time on the low-field system was 21.3 ms with the low receiver bandwidth and 4.3 ms on the 1.0-T MR unit. The amount of chemical shift artefacts was the same on both systems. DISCUSSION: On low-field MR systems SNR is markedly improved by small read-out gradients and a low receiver bandwidth (factor 3 vs 5-16 in comparison with the 1.0-T MR unit). However, an optimal homogeneous magnetic field is required, since inhomogeneities may create severe geometrical distortion.

Artifacts↗
PubMed1997

[Comparison of diagnostic sensitivity in meniscus diagnosis of MRI examinations with a 0.2 T low-field and a 1.5 T high field system].

The aim of this study was to evaluate the reliability of a low field strength MRI unit (0.2 T; Esaote, Biomedica) and a high field strength MRI unit (1.5 T; Siemens) in detecting meniscal lesions. Twenty patients were investigated on a 0.2-T low-field MRI unit and a 1.5-T high-field MRI unit for meniscal lesions. Evaluation was performed of four meniscal compartments (anterior and posterior medial and lateral meniscus), for a total of 80 observations. The reliability of diagnosis was ranked qualitatively on a three-point scale. Investigations of the high-field MRI unit revealed a meniscal tear in 6 patients and ruled out a tear in 14 patients. Evaluation of individual meniscal compartments revealed diagnosis with high confidence in 58 observations and with moderate confidence in 22 observations. Investigations of the low-field MRI unit revealed a meniscal tear in 5 patients and ruled out tears in 15 patients. Evaluation of individual meniscal compartments revealed diagnosis with high confidence in 39 observations, with moderate confidence in 38 observations, and with low confidence in 3 observations. The diagnosis in high- and low-field images was identical in 98.7% of cases; in one patient observations from the high-field unit changed the therapeutic management. Diagnostic reliability was significantly higher with high-field strength MR imaging. Low field strength MR imaging shows comparatively high diagnostic accuracy for meniscal lesions compared to high field strength imaging; however, we demonstrated a significantly higher confidence in diagnosis with high-field MR imaging.

Adult↗
PubMed1997

[Imaging of the middle ear. CT and MRI].

High-resolution computed tomography (HRCT) provides excellent contrast between osseous structures, air and soft tissue in conjunction with high spatial resolution. Therefore, thin-section HRCT with bone window setting is the method of choice for the examination of the middle ear structures. The indications are acute and chronic inflammatory changes, cholesteatoma and tumor, the "postoperative middle ear", and malformations. In most cases, HRCT enables differentiation between inflammatory changes, cholesteatoma, and tumor. The excellent depiction of subtle osseous details enables the identification of erosions of the ossicles or of the bony walls of the mastoid cells, of osseous defects of the tegmen, of the bony labyrinth, and of the tympanic course of the facial canal. In addition, HRCT enables excellent depiction of reconstructions of the ossicles or prosthesis of the ossicles. Although HRCT is the first method of choice, magnetic resonance imaging (MRI) may provide additional information and lead to a more accurate diagnosis in some cases. This is explained by the excellent soft tissue contrast provided by MRI. In addition, MRI offers the possibility of using various pulse sequences and the administration of i.v. contrast material. Therefore, MRI may allow the differentiation between inflammatory changes, cholesteatoma, and tumor in those cases in which accurate diagnosis cannot be made by HRCT. The differentiation between a meningocele or meningoencephalocele and other entities such as tumors or cholesteatoma can be established by MRI. Furthermore, MRI can accurately depict cases of labyrinthitis or of neuritis of the facial nerve or of intracranial disease caused by middle ear processes, while this is not always possible by HRCT. In summary, HRCT of the middle ear is the method of choice, but MRI may provide supplementary information in those cases in which accurate diagnosis cannot be established by HRCT.

Ear Diseases↗
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

Radiographic detection of intrabronchial malpositions of nasogastric tubes and subsequent complications in intensive care unit patients.

OBJECTIVE: The aim of our study was to illustrate the radiographic spectrum of the intrabronchial malposition of nasogastric tubes and subsequent complications, and to discuss the role of radiography in the detection of such malpositions. DESIGN: Retrospective clinical investigation. SETTING: Tertiary care university teaching hospital. PATIENTS AND METHODS: We reviewed chest radiographs of 14 intensive care patients with nasogastric tubes malpositioned in the tracheobronchial tree. The site and anatomic location of the malposition were recorded. Complications due to tube malpositioning were monitored on follow-up radiographs and on computed tomographic examinations, which were available in 4 patients. RESULTS: Nine of 14 nasogastric tubes were inserted in the right and 5 in the left tracheobronchial tree. Tube tips were malpositioned in the lower lobe bronchi (50%), the intermediate bronchus (36%), and the main bronchi (14%). There was perforation of the bronchial system with subsequent pneumothorax in 4 patients. In 4 other patients, pneumonia developed at the former site of the malpositioned tube tip. Radiographic detection of nasogastric tube malpositioning was prompt in 9 patients and delayed in 5 patients. CONCLUSIONS: Whereas clinical signs of nasogastric tube malpositioning in intensive care patients may be absent or misleading, chest radiography can accurately detect nasogastric tube malpositions in the tracheobronchial tree, may prevent complications, and avoid the use of further costly or invasive diagnostic techniques.

Adult↗
PubMed1996

Field strength dependence of MRI contrast enhancement: phantom measurements and application to dynamic breast imaging.

Differences in MRI-measured contrast enhancement have been used for tissue characterization, particularly for the characterization of mammary tumours. T1 weighted spoiled gradient echo sequences have usually been acquired for this purpose and relative signal intensity increase (Srel) has been determined to quantify contrast uptake. The field strength dependence of this technique is evaluated in this paper by phantom measurements. Srel is compared with the recently introduced "enhancement factor" (EF) and "contrast uptake equivalent" (CE) as a quantitative assessment parameter for contrast uptake. Enhancing tissues were simulated with water phantoms doped with increasing concentrations of Gd-DTPA. Spoiled gradients echo images (FLASH-2D) were obtained on a 0.2 T and 1.5 T MR system. Srel, EF and CE were determined and the results of the phantom measurements were applied to typical types of breast tissues. Srel showed a strong dependence on the magnetic field strength and was greater at higher field strengths. This is because Srel correlates positively with the native T1 which is longer at higher field strengths. Conversely, the EF and CE almost eliminated the distorting influences of the magnetic field strength. CE provided a good approximation of the actual contrast uptake. In practice, the dependence of Srel on the magnetic field strength might cause malignant lesions to be misclassified as benign at low field strengths. Either Srel criteria should be adjusted to magnetic field strength or EF and CE should be used instead of Srel for tissue characterization with dynamic contrast-enhanced MRI.

Breast Neoplasms↗
PubMed1996

Power Doppler versus color Doppler imaging in renal allograft evaluation.

The purpose of this study was to evaluate the impact of PDS compared to conventional CDI in the followup of 72 renal allograft patients. Renal allograft vascularization, assessed by PDS and CDI, was scored from 0 to 4, where 0 was the cortical "blush" and 4 was residual central perfusion. These scores were correlated with the resistive index, serum creatinine levels, hematocrit, and, in 35 cases, biopsy results. PDS scores of renal perfusion were one grade lower than CDI scores in 59 of 72 patients and two grades lower in two of 72 patients. A statistically significant correlation was found between PDS scores and the RI (r2 = 0.6, P < 0.05). However, no significant correlation was found between PDS scores and creatinine levels or hematocrit values. PDS scores are not related to histologic findings in renal allograft dysfunction. Overall, five biopsy-related arteriovenous fistulas were detected, two of which were missed on the initial PDS examination. In conclusion, PDS provides more complete visualization of the renal allograft vessel tree than CDI. However, biopsy-related arteriovenous fistulas are better seen by CDI.

Biopsy↗
PubMed1996

[Bilateral acute retrobulbar space-occupying lesion within the scope of thrombolytic therapy in myocardial infarct--a case report].

A 51-year-old male patient with circulatory arrest and ventricular fibrillation was brought to the emergency department after restoration of spontaneous circulation. ECG presented signs of acute anterolateral myocardial infarction. Thrombolytic therapy according to the Neuhaus scheme was initiated. After administration of 60 mg rt-PA continuously increasing protrusion and hyposphagma of both eyes (left > right) and left-sided monocle-hematoma was observed. CCT showed shadowing of sinus ethmoidales frontales, broadening of the left lateral rectus muscle and retrobulbar volume increase without any signs of recent bleeding. The ophthalmologist had to answer the question if there was, in spite of the massive retrobulbar volume increase, a sufficient blood supply for both eyes. Ophthalmoscopically there were no signs of intraretinal bleeding or retinal ischemia. Intraocular circulation was checked by color Doppler sonography: Ophthalmic artery, the short posterior ciliary arteries and central retinal artery of both eyes showed very low, but definitely positive bloodflow. Further course showed a constant trend towards higher systolic bloodflow velocities in all eye vessels, verified by color Doppler sonography. Computer perimetry, performed after the recovery of the patient, revealed a visual field defect, which was related to a breakdown of the flow in a ciliary artery rather than to damage due to compression of the optic nerve. Possible reasons of the retrobulbar volume increase under thrombolytic therapy are discussed.

Blood Flow Velocity↗
PubMed1995

[Malignant neoplasms after kidney transplantation: value of an annual radiological screening program].

PURPOSE: To evaluate the prevalence of malignant neoplasms after renal transplantation by means of a radiological screening programme and to determine the role of some clinical and demographic parameters concerning pathogenesis of these malignancies. MATERIAL AND METHODS: Between November 1992 and June 1994 in a prospective study 504 consecutive renal allograft recipients (331 m, 173 f) aged 51 +/- 13 years underwent routine abdominal ultrasound examinations including the renal transplant and p.a. and lateral chest x-rays once a year. RESULTS: This screening programme revealed 11 malignant neoplasms in 11 patients (2.2%). We detected 6 renal cell carcinomas (RCC) in the patient's native kidneys, two RCCs in two renal allografts, two non-Hodgkin-lymphomas in the liver and the renal allograft, respectively, and one ovarial carcinoma. Patients with renal cell carcinomas in the native kidneys were significantly older than allograft recipients without tumors. The presence of acquired cystic kidney disease (ACKD) seems to be an additional risk for the development of RCC. There were no significant differences in the time on dialysis, the time with functional renal allograft, and the immunosuppressive therapy. CONCLUSION: Yearly abdominal ultrasound screening including the renal allograft is a valuable tool for the early detection of neoplasms in asymptomatic renal allograft recipients. However, routine yearly chest x-rays should not be performed in renal allograft recipients without preexisting tumours.

Adult↗
PubMed1995

Case report: epidermoid cyst of the floor of the mouth: diagnostic imaging by sonography, computed tomography and magnetic resonance imaging.

Epidermoid and dermoid cysts are rare benign tumours which may occur anywhere in the body. About 7% of them are found in the head and neck region and only 1.6% are located within the oral cavity. Pre-operative imaging of these lesions provides important diagnostic and anatomical information with regard to the patient's therapeutic management. This case report describes imaging findings in a patient with an extensive epidermoid cyst located within the sublingual space.

Adult↗
PubMed1994

[Imaging in parotid tumors: US versus MRT].

27 patients, clinically suspected of having parotid tumours, were examined prospectively by sonography (high frequency linear array) and MRI (1.5 T, T1- and T2-weighted SE sequences before, and T1-weighted SE sequences after contrast). In 23 patients, 25 intraglandular tumours were demonstrated (two were multicentric); they consisted of 6 malignant parotid tumours, 11 pleomorphic adenomas, 7 cystadenolymphomas and one oncocytic adenoma. 4 patients had extraglandular tumours. All tumours were demonstrated by either method, but two extraglandular tumours were incorrectly diagnosed by sonography as being intraglandular and 8 tumours (28%) were not completely delineated by sonography. MRI localised the tumours correctly in all cases and demonstrated all lesions accurately, independent of their position or size. In summary, sonography appears suitable as the primary imaging method in the investigation of parotid tumours but in case of large, parapharyngeal or malignant tumours, MRI is clearly superior to sonography.

Adolescent↗
PubMed1994

[Emergency management of ruptured/dissecting aortic aneurysm--diagnosis and therapeutic strategies].

Between December 1991 and January 1994 fifteen patients with a ruptured abdominal aortic aneurysm and seven patients with a dissecting aortic aneurysm were treated in our emergency department. Dissection/rupture of an aortic aneurysm is still a dramatic event with poor outcome, whereby survival depends largely on early diagnosis. In most cases the diagnosis can be made with reasonable assurance by history taking and physical examination. The most frequent differential diagnoses are pulmonary embolism and myocardial infarction (thoracic aneurysms) and renal or biliary colic and lumbago (abdominal aneurysms). The largest delay in commencing therapy is caused by patients' hesitation to call the Emergency Medical Service. Chest X-ray, echocardiography and abdominal sonography are of high diagnostic value, computed tomography confirms the diagnosis in most cases. Our Emergency Department provides the facilities for rapid diagnosis and interdisciplinary preoperative management of dissecting/ruptured aortic aneurysms.

Adult↗
PubMed1993

[The sonography of laryngeal cysts].

To evaluate the sonographic appearance of laryngeal cysts, ultrasound examinations of 7 patients were evaluated retrospectively. The ultrasound studies were correlated with endoscopic findings. In two cases, the diagnosis was confirmed histologically, and in 4 patients, a CT examination was additionally performed. The endolaryngeal space could be well seen if the thyroid cartilage was not calcified (n = 6), whereas in one patient, the endolaryngeal part of the cyst could not be seen because of complete calcification of the thyroid cartilage. The laryngeal cysts presented as unechoic (n = 4) or hypoechoic (n = 3) masses, which demonstrated smooth margins in all cases and ranged in size from 6 to 38 mm. In three cases, the cyst was located in the endolaryngeal space, and in 4 cases, it extended cranial of the thyroid cartilage into the pre-epiglottic space. All cysts were closely related to the inner surface of the thyroid cartilage, from which they were delineated by a thin hyperechoic band in all cases.

Adult↗