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G Heinz-Peer

Publications and source records attributed to G Heinz-Peer.

At least 19 recordsLinked to original sources
PubMed2005

[Imaging techniques and their impact in treatment management of patients with acute flank pain].

The purpose of this overview is to provide a general summary of the imaging techniques applied at the Vienna Hospital for the investigation of acute flank pain and the diagnosis of stone disease and the evaluation of their efficacy and impact on therapy management. The number of publications on the issue of "intravenous urography (IVU) vs computed tomography (CT)" is abundant; in recent years, advocates of CT make up the majority. In the Department of Urology at the Vienna Hospital, conventional techniques such as ultrasound and IVU besides UHCT still play an important role. This overview presents the advantages and disadvantages of the various imaging techniques for diagnosis of stone disease and evaluates their significance regarding therapy management of patients with acute flank pain.

Flank Pain↗
PubMed2005

[MR urography: principles, examination techniques, indications].

MR urography is an evolving and promising technique in the evaluation of the urinary tract. MR urography is currently considered the method of choice for imaging of the renal parenchyma and the collecting systems in patients who cannot undergo routine radiographic studies such as pregnant women, pediatric patients, patients allergic to iodinated contrast agents, or patients with impaired renal function. The future development of MR urography in terms of functional, cellular, and molecular imaging is presently the subject of research. The ability of MR imaging to provide quantitative functional information (e.g., on blood flow, perfusion, glomerular filtration rate, and excretion as well as urine drainage) in addition to morphologic assessment of the parenchyma and the collecting system could lead to a single, "all-in-one approach" examination technique.

Humans↗
PubMed2005

[Virtual multislice computed tomography cystoscopy for evaluation of urinary bladder lesions].

The introduction of multislice computed tomography (MDCT) with the possibility of acquiring isotropic datasets has been an ideal prerequisite for development of virtual MDCT cystoscopy. Remarkable technical progress regarding post-processing of high-resolution 3D datasets as well as a considerable reduction of the time required for post-processing made it possible to introduce virtual MDCT cystoscopy into the clinical routine. 3D post-processing that often required 7-8 h when virtual endoscopy techniques were first developed can now be performed in less than 5 min after transfer of data to the 3D workstation. With the limitations and contraindications of conventional cystoscopy in mind, virtual MDCT cystoscopy may be seen as a valuable alternative to conventional cystoscopy for evaluation of hematuria.

Cystoscopy↗
PubMed2001

[Urological and nephrological emergency--value of diagnostic imaging].

Many diseases of the kidneys and the urinary tract may develop to urinary emergencies. A prompt evaluation of these critical situations is of utmost importance concerning therapeutic consequences, and implicates a considerable challenge for the radiologist. The use of the appropriate imaging method allows rapid diagnosis, and thus enables optimal therapeutic management. In this article we describe the most important urinary emergencies: urolithiasis, hydronephrosis, acute renal infection, acute obstruction, testicular torsion, complications after renal transplantation, and urinary trauma. Aetiology and pathogenesis of the specific entities are described as well as the use of the adequate imaging method. In addition, especially for CT examinations precise imaging techniques are reported. Complications and differential diagnosis of the specific emergencies are mentioned.

Acute Disease↗
PubMed2001

[Diagnostic imaging in gynecological emergencies].

A wide spectrum of differential diagnosis exists in case of gynaecological emergencies which also includes gastrointestinal and urologic diseases. Radiologic imaging primarily bases on sonography, computed tomography and magnetic resonance imaging are used for subsequent evaluation. The detailed algorithm is oriented on clinical symptoms and signs. The most important signs are left and right lower quadrant abdominal pain, vaginal bleeding, and sudden onset of pain in the breast.

Acute Disease↗
PubMed2000

Detection of focal hepatic lesions: comparison of unenhanced and SHU 555 A-enhanced MR imaging versus biphasic helical CTAP.

The purpose of this study was to compare the diagnostic sensitivity of unenhanced magnetic resonance (MR) imaging, and MR imaging with a new superparamagnetic iron oxide (SPIO)-enhanced contrast agent (SHU 555 A) with biphasic helical computed tomography during arterial portography (CTAP) in patients with focal liver lesions. Eighteen patients with a total of 91 (78 malignant, 13 benign) proven liver lesions underwent unenhanced short tau inversion recovery (STIR), T2-weighted (T2-w) TSE, and SHU 555 A-enhanced T2-w turbo spin-echo (TSE) MR imaging and biphasic helical CTAP. The standard of reference was histopathologic analysis of resected specimens in 59 lesions, intraoperative ultrasound with biopsy in 20 lesions, and CT-guided biopsy and follow-up in 12 lesions. Diagnostic performance of the imaging modalities was compared quantitatively and qualitatively by assessing lesion involvement in liver segments. There were 68 lesions detected on unenhanced T2-w TSE, which resulted in a sensitivity of 75%. With the STIR sequence, 76 lesions were detected, for a sensitivity of 84%, and with SHU 555 A-enhanced MRI, 84 lesions were detected, for a sensitivity of 92%. CTAP detected 88 lesions, for a sensitivity of 97%. The accuracy for unenhanced T2-w TSE was 98%, for STIR 99%, for enhanced-MRI 100%, and for CTAP 95%. The specificity was 100% for SHU 555 A-enhanced MRI and 95% for CTAP. SHU 555 A-enhanced MRI was superior to nonenhanced MRI (P < 0.05) and equivalent to CTAP in terms of sensitivity. Due to the absence of false-positive results on SHU 555 A-enhanced MRI, the specificity and accuracy of enhanced MRI were higher than those of CTAP, but the difference was not statistically significant (P = 0.134).

Adult↗
PubMed1999

[Characterization of adrenal gland space-occupying lesions. Can diagnostic imaging replace biopsy?].

This paper describes the diagnostic value of new imaging techniques in characterization of adrenal masses and evaluates the role of adrenal biopsy. For differentiation of benign and malignant adrenal lesions, sensitivities and specificities of 85-100% can be reached by unenhanced computed tomography (CT) methods, chemical shift techniques in magnetic resonance imaging (MRI), delayed enhanced CT techniques, and by evaluation of wash-out curves in contrast-enhanced CT. The diagnostic value of all CT techniques depends on threshold values. The value of dynamic contrast-enhanced MRI is under discussion and should be reevaluated by using delayed enhanced series. Biochemical and scintigraphic methods (NP 59 iodine iodomethyl-norcholesterol and MIBG meta-iodobenzylguanidine scintigrams) are valuable for the diagnosis of functional adrenal masses; however, they do not allow differentiation of benign and malignant tumors. According to excellent results of new imaging techniques in characterization of adrenal masses, the indications for fine-needle aspiration biopsy have already regressed, as have complications associated with this invasive technique.

Adrenal Gland Diseases↗
PubMed1999

Paclitaxel and carboplatin in patients with metastatic transitional cell cancer of the urinary tract.

OBJECTIVES: The combination of methotrexate, vinblastine, doxorubicin, and cisplatin (MVAC) is currently considered the most effective chemotherapy for metastatic transitional cell cancer (TCC) of the urinary tract, but because of its considerable toxicity, alternative regimens appear very interesting. We evaluated the efficacy and toxicity of a combination of paclitaxel and carboplatin as first-line therapy for metastatic TCC. METHODS: Thirty-two patients (8 women, 24 men; mean age 67.03 years, range 50 to 79) with metastatic TCC of the bladder or upper urinary tract were included in the study. Paclitaxel (175 mg/m2) was given as a 3-hour intravenous infusion, carboplatin was dosed to an area under the plasma concentration curve of 5 mg/m/min calculated according to the Calvert formula [(creatinine clearance + 25) x 5] as a 30-minute intravenous infusion immediately after paclitaxel. Response evaluation was performed after every 2 cycles and additional therapy depended on response. The maximum number of cycles was 6. RESULTS: With a mean follow-up of 13.1 months (range 2 to 28), 23 of 32 patients responded to treatment (response rate 71.9%), with 31.3% complete remission (CR) (10 of 32) and 40.6% partial remission (PR) (13 of 32). Four patients (12.5%) had stable disease, and 5 patients (15.6%) showed progression. These results compare well with the outcome after MVAC. Toxicity was mainly characterized by neurotoxicity grade 3 and 4 in 9.4%, grade 3 and 4 leukopenia in 37.5%, and grade 3 thrombocytopenia in 3.1% of the patients. No nephrotoxicity was observed, but all patients developed alopecia. Time to progression after CR was a mean of 7.0 months (range 4 to 13) and after PR a mean of 5.9 months (range 2 to 9). CONCLUSIONS: Paclitaxel/carboplatin is an effective therapy for metastatic TCC, with low toxicity.

Aged↗
PubMed1999

Magnetic resonance imaging in hemophilic children: value of gradient echo and contrast-enhanced imaging.

The purpose of this study was to determine the value of Gradient Echo imaging for the evaluation of cartilage (3D fatsat) and blood products (2D Hemoflash), and the use of contrast enhanced SE imaging for the evaluation of synovial changes, in comparison to the clinical evaluation of children with hemophilia A. We investigated 21 joints in 16 patients with evidence of hemophilia A (mean age 11.3+/-2.1 years). In all patients, clinical examination, plain film radiographs, and MR evaluation were performed magnetic resonance imaging (MRI) was performed by using sagittal T1 SE and T2 SE images, as well as 3D fatsat GE and 2D GE images. Axial and sagittal T1 weighted SE images were obtained before and after contrast application. Findings from the clinical examination and MR imaging, regarding the evaluation of blood, synovia, and cartilage were compared. Clinical examination revealed evidence of a bleeding episode in 12 joints (57.1%), whereas MRI revealed evidence of blood or blood products in 15 joints (71.4%). Clinical investigations, including bleeding scores, pain scores, and physical examination scores did not correlate with MR findings. Due to the MR findings in 6 of 16 patients, therapeutic management was changed from on demand to prophylactic therapy. MR imaging with gradient echo and contrast-enhanced sequences is more sensitive than clinical examination for the detection of blood products in children with hemophilia. Its ability to demonstrate potentially early stages of cartilage or synovial alterations might assist in therapy planning. Clinical scores might underestimate effects of hemophilia.

Ankle Joint↗
PubMed1999

[Differential diagnosis of space-occupying adrenal masses].

Computed tomography (CT) and magnetic resonance (MR) imaging are first line modalities in the evaluation of patients with adrenal gland masses, and have the potential to be very accurate for the localization of adrenal gland masses in patients with diseases associated with hyperfunctioning conditions of the adrenal gland. Both CT and MR imaging allow a specific diagnosis of acute adrenal hemorrhage, adrenal myelolipoma, and adrenal cysts. CT is also helpful in the assessment of patients with Addison's disease, particularly the subacute form secondary to granulomatous diseases. Quantitative evaluation of adrenal masses on unenhanced CT scans and/or qualitative analysis on chemical-shift MR imaging have been shown to be accurate in distinguishing adrenal adenomas from non-adenomas. Attenuation of 11 HE or less on unenhanced CT scans and/or signal loss on opposed phase MR images indicate adenoma with a high specificity and acceptable sensitivity. More recently, delayed-enhanced CT has yielded higher sensitivity and specificity values in distinguishing between adrenal adenomas and non-adenomas than both unenhanced CT and chemical-shift MR imaging do. On delayed-enhanced CT scans, adrenal adenomas exhibit a greater washout of contrast material than do adrenal non-adenomas. Therefore, adrenal non-adenomas have significantly higher attenuation than adenomas on delayed-enhanced CT scans obtained at several arbitrarily chosen time points (3-60 min) after the initiation of contrast material administration.

Adenoma↗
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

Characterization of adrenal masses using MR imaging with histopathologic correlation.

OBJECTIVE: The purpose of this study was to evaluate the sensitivity, specificity, and accuracy of MR imaging in the characterization of adrenal masses by correlating imaging findings with histopathologic results. In addition, adrenal tumors that were of an indeterminate nature on MR imaging were analyzed. SUBJECTS AND METHODS: For 114 patients with 134 adrenal masses, MR findings were compared with histologic results. In all patients, MR imaging was performed using T2-weighted fast spin-echo imaging and unenhanced and gadolinium-enhanced T1-weighted spin-echo imaging. Chemical-shift imaging was performed in 92 patients and dynamic gadolinium-enhanced studies in 108 patients. Chemical-shift images were analyzed quantitatively and qualitatively, and dynamic gadolinium-enhanced studies were qualitatively assessed. RESULTS: The sensitivity of MR imaging in differentiating between benign and malignant adrenal masses was 91%, the specificity was 94%, and the accuracy was 93%. The diagnosis at MR imaging differed from that at histology in 12 (9%) of 134 patients. Results of quantitative analyses of chemical-shift imaging techniques showed significant differences between adenomas and nonadenomas (-36.0% versus -3.7%; p < .001). Qualitative analysis provided a similar diagnostic confidence compared with quantitative analysis. Both chemical-shift and dynamic gadolinium-enhanced studies proved to be unreliable in characterizing borderline tumors (epithelial tumors with high malignant potential). Moreover, such imaging failed to allow correct diagnosis of adenomas in two patients. CONCLUSION: The characterization of an adrenal mass can be made with high sensitivity and specificity using MR imaging. The increased reliance on MR imaging seems to be based mainly on findings from chemical-shift and dynamic gadolinium-enhanced studies. The need to perform histologic sampling of incidentally discovered adrenal masses may be reduced to some problematic lesions, which will remain during the era of MR imaging.

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↗
PubMed1999

Anemia and carnitine supplementation in hemodialyzed patients.

Carnitine supplementation in hemodialyzed patients was studied in a double-blinded, randomized, controlled trial in order to elucidate the effect of intravenous carnitine on renal anemia in patients treated with recombinant human erythropoietin (rHuEPO). Twenty stable hemodialysis (HD) patients received intravenous L-carnitine after each dialysis session in a dosage of 5 (N = 15) and 25 (N = 5) mg/kg, respectively, together with intravenous iron saccharate (20 mg/HD session) for four months and without iron for a further four months. Twenty patients received placebo instead of carnitine with an identical iron regimen. After a run-in phase of six months with a stable rHuEPO requirement, the rHuEPO dose was adjusted monthly when necessary to maintain target hemoglobin levels. At study entry (T0), plasma and red blood cell carnitine levels did not correlate significantly with the rHuEPO requirement. However, plasma free and total carnitine levels showed a significant negative correlation with erythrocyte survival time at T0. After four months of coadministration of intravenous iron and L-carnitine (T4), the rHuEPO requirement decreased in 8 of 19 evaluable HD patients. In these responders, the weekly rHuEPO dose was decreased significantly by 36.9+/-23.3% (183.7+/-131.7 at T0 vs. 126.6+/-127.9 U/kg/week at T4, P < 0.001). The rHuEPO requirement, however, was unchanged when all carnitine-treated patients were compared between T0 and T4 (T0: 172.0+/-118.0 vs. T4: 152.3+/-118.8 U/kg/week, P = 0.07, NS), but the erythropoietin resistance index decreased significantly in this group (T0: 16.0+/-11.0 vs. T4: 13.6+/-10.5 U/kg/week/g of hemoglobin, P < 0.02). The erythrocyte survival time was measured in five HD patients treated with iron and carnitine at T0 and T4. Two out of these patients were carnitine responders and showed an increase of erythrocyte survival time of 15 and 20%, respectively. After the withdrawal of iron supplementation, the rHuEPO requirement increased comparably in both L-carnitine- and placebo-treated patients during four more months. According to our data, L-carnitine, in addition to iron supplementation, may have an effect on erythropoietin resistance and erythrocyte survival time in HD patients. More than half of our patients, however, showed no benefit. Further studies to identify those HD patients who might have a benefit of carnitine supplementation, as well as studies concerning the optimal dosage, duration, and way of administration of carnitine supplementation and its mechanism of action, are required.

Adult↗
PubMed1998

Role of magnetic resonance imaging in renal transplant recipients with acquired cystic kidney disease.

OBJECTIVES: To evaluate the impact of magnetic resonance imaging (MRI) in renal transplant recipients whose ultrasound (US) examinations of the native kidneys have met the criteria of acquired cystic kidney disease (ACKD). METHODS: The US scans of 840 renal allograft recipients were prospectively studied. In addition, 46 of 169 patients diagnosed with ACKD by US scans underwent MR examination. MRI protocols included (a) T1 and T2-weighted fast spin echo imaging, (b) T2-weighted gradient echo imaging, and (c) gadolinium-enhanced T1-weighted imaging in 7 patients with evidence of complex cysts. In the case of complex lesions, both US and MRI follow-up examinations were performed between 6 and 12 months after the prior examination. RESULTS: US examination showed ACKD in 169 of 840 patients. In addition, US revealed 8 patients with renal cell carcinomas (RCC). Of these 8 patients, 7 had evidence of ACKD. The median number of cysts depicted on US examination in native kidneys of renal transplant recipients was 3 (range 0 to 10) on both sides. MRI revealed significantly more and smaller cysts compared to US. The median number of cysts was seven on the left and nine on the right native kidneys, respectively. MRI revealed 18 complex lesions in 7 patients. Thirteen of 18 complex lesions were undetected by US. CONCLUSIONS: MRI is superior to US in depiction of simple and complex lesions of native kidneys in renal allograft recipients. MRI exhibits no overestimation of the prevalence of ACKD on the basis of the US criteria already mentioned. Advantages of MRI do not justify routine screening tests by this imaging modality. However, MRI should be used for further evaluation of complex lesions detected by US.

Adult↗
PubMed1998

Implantable microballoons: an attractive alternative in the management of intrinsic sphincter deficiency.

PURPOSE: All current bulking agents employed for treating stress urinary incontinence (SUI) have significant limitations due to various side effects, technical difficulties and inadequate long-term results. Implantable microballoons were therefore tested as a new therapeutic modality for female urinary incontinence. MATERIAL AND METHODS: The microballoons are implanted with a new system which consists of the self-detachable cross-linked silicone balloon, biocompatible filler material and a delivery system. Nineteen female patients (mean age 63.3 years) with SUI grade 1 or 2 were studied prospectively. Using the Blaivas-Olsson classification, 6 patients had stress incontinence type I, 4 had type II and 9 had type III. Three to seven balloons (mean 4.2) were implanted per patient. Patients were followed up with pad tests (g) and determination of leak point pressure (LPP; cm H2O) and maximal urethral closing pressure (Pura max; cm H2O) at 1, 3, 6, 12 and 18 months. RESULTS: The biocompatibility of the microballoons was excellent. No significant adverse events were associated with the procedure. With a mean follow-up of 14.4 months (range 10-18) 42.1% (8/19) of the women are dry. In the latter the pad test improved from a preoperative mean of 22.6 g (2-75) to 0 and the LPP increased from a preoperative mean of 38.5 cm H2O (25-60) to 80.5 cm H2O (68-106). 36.8% (7/19) of the patients showed significant improvement of their incontinence. In this group the pad test improved from a preoperative mean of 39.1 g (8-112) to 9.7 g (2-29) and LPP from a mean of 37.1 cm H2O (25-50) to 42.0 cm H2O (30-58). In 4 patients (21.05%) the technique failed. Seven of the 8 cured patients had type III incontinence; the eighth patient had type I incontinence. It failed in all patients with type II incontinence. CONCLUSION: The implantation of microballoons is a safe, well-tolerated and clinically effective modality for the treatment of type III SUI, i.e. intrinsic sphincter deficiency.

Adult↗