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M Strotzer

Publications and source records attributed to M Strotzer.

86 records · Page 5Linked to original sources
PubMed1995

Renal arteries: evaluation with optimized 2D and 3D time-of-flight MR angiography.

PURPOSE: To compare two-dimensional (2D) and three-dimensional (3D) time-of-flight (TOF) techniques in magnetic resonance (MR) angiography of renal arteries. MATERIALS AND METHODS: In 46 patients, MR angiography was performed with 3D tilted optimized non-saturating excitation (TONE), 3D fast imaging with steady precession (FISP), and 2D fast low-angle shot (FLASH) during breath holding. Intraarterial angiography was used as a reference. MR angiograms were evaluated for stenoses, length of renal arteries, accessory arteries, venous overlap, and image quality. RESULTS: The 3D TONE sequence was best for detection of severe stenoses (sensitivity, 100%; specificity, 89%), delineation of accessory arteries, and image quality. Overlap of renal veins was the most important disadvantage of 2D FLASH. Decreased saturation effects, however, can be advantageous in 2D TOF imaging. CONCLUSION: Use of the 3D TONE sequence provided improved image quality and diagnostic value compared with 3D FISP technique. The 2D TOF sequence can be useful in combination with the 3D TONE sequence.

Adult↗
PubMed1995

Noninvasive assessment of renal artery stenosis. A comparison of MR angiography, color Doppler sonography, and intraarterial angiography.

The purpose of this study was to evaluate MR angiography (MRA) and color Doppler sonography as noninvasive screening methods in suspected renovascular hypertension. Fifty-five consecutive patients with arterial hypertension were examined prospectively using high resolution 3-D TOF MRA and color Doppler sonography. Intraarterial angiography was the standard of reference. Stenoses of 60% or more were regarded as significant. MR angiograms were evaluated by 3 independent observers who studied 110 main renal arteries. All 8 significant stenoses and 2 occlusions were correctly classified with MRA while one 60% stenosis was underestimated by color Doppler sonography. Mild stenoses were overestimated by MRA in 4 and by color Doppler sonography in 6 cases. A drawback of both methods was the large number of not evaluable arteries (6 in MRA, 11 in color Doppler sonography). These arteries were regarded as pathologic because stenosis could not be excluded. Due to this fact specificities of MRA and color Doppler sonography were 90% and 85% respectively. Accessory vessels were detected in 47% (8/17) by MRA and in 0% (0/17) by color Doppler sonography.

Adult↗
PubMed1994

[Sclerotherapy of the internal spermatic vein in varicocele. Significance of normal anatomical variants].

During a period of four years, 386 patients with left sided varicoceles were treated by sclerotherapy of the left internal spermatic vein. This was successful in 93.8%. The most common complication was perforation of the vein in 6.2%. Technical success and complications depended on anatomical variations. Of particular significance was Bähren type IVb (competent main vein, incompetent collaterals) which occurred in 18.9%. This accounted for 66.5% of all perforations and 54.2% of unsuccessful interventions. The recurrence rate was 3.8%.

Adolescent↗
PubMed1993

Detection of fat in a renal cell carcinoma mimicking angiomyolipoma.

The authors report a case of renal cell carcinoma in which computed tomography (CT) revealed fatty tissue and calcification within a solid renal mass. The detection of a mass with negative CT numbers at CT and increased echogenicity at ultrasound led to the incorrect diagnosis of angiomyolipoma (renal hamartoma). The presence of intratumoral calcification should have prompted further evaluation because angiomyolipomas usually do not calcify. The authors do not believe that the nonsurgical approach to angiomyolipomas should be abandoned.

Adipose Tissue↗
PubMed1991

HLA typing in families with multiple cases of rheumatoid arthritis.

Thirty one white patients from 14 families with multiple cases of rheumatoid arthritis (RA) and 42 of their healthy relatives were completely HLA typed. In contrast with class I antigens, the class II antigens DR1 and DR4 were significantly more common in the patients than in a group of 200 healthy local white controls (DR1: 32% v 12%; DR4: 48% v 28%, in patients and controls respectively). Owing to the small number of cases the data from this study were combined with those of published reports. Examination of patients for DR1 and DR4 homozygosity and DR1/4 heterozygosity showed an increase of DR1 homozygous patients, which was not statistically significant. There was no striking deviation from random expectation in haplotype sharing of affected sib pairs. These results are compatible with a dominant influence of DR1 and DR4 in the mode of inheritance. The nearly random haplotype sharing and the molecular relation between DR1 and DR4 support the hypothesis of a direct influence of these antigens in the pathogenesis of RA. Only 68% of the patients in this study possessed either DR1 or DR4, possibly indicating a subtype of RA which is independent of HLA. Clinical and serological variables were measured and indicated no significant difference between DR1 (or DR4) positive and DR1 (or DR4) negative disease. In this small group of patients the clinical course of RA seemed to be determined mainly by other genetic or environmental factors.

Arthritis, Rheumatoid↗
PubMed1991

[Measuring regional blood flow in evaluating CT-controlled lumbar sympathetic neurolysis in arterial occlusive disease].

A prospective study was designed to evaluate the effect of CT-guided lumbar sympathectomy in PAOD using the following investigations: 1: laser flowmetry, 2. thermography, 3. plethysmography, 4. thallium scintigraphy. A significant improvement of perfusion was shown. The results of thallium scintigraphy disproved the often claimed steal effect of the muscle perfusion in favor of an increased skin perfusion. 80% of the treated patients experienced relief of their pain. Chemical sympathectomy proved to be as effective as the surgical procedure.

Arterial Occlusive Diseases↗
PubMed1991

Is ultrasonography a reliable method for evaluation of fragment clearance after biliary ESWL? A prospective, blinded study of two independent ultrasound units.

Ultrasound is the preceding method for evaluation of fragmentation and subsequent fragment clearance from the gallbladder. Considering the methodological shortcomings of ultrasonography, this study was therefore designed to investigate the degree of conformity between two independent ultrasound units. In our protocol patients were evaluated for fragments two weeks and three, six, nine and twelve months after ESWL. A restricted number of experienced sonographers in two independent ultrasound units examined the patient without knowledge of the other unit's findings. A total of 62 examinations have been carried out so far. Complete or sufficient conformity with a difference in size of 0-3mm was achieved in 24 examinations. Seven examinations revealed differences of 4-13 mm. In 31 cases the diagnosis of a stone-free gallbladder has been made, but only in 25 cases this could be confirmed by the other ultrasound unit. In six examinations a small fragment of less than 5mm was found by the respective other sonographer. We conclude that the diagnoses of a stone-free gallbladder after ESWL should be reconsidered by a second independent and experienced sonographer.

Adult↗
PubMedDate not supplied

Post-traumatic pseudocyst of the spleen: sclerotherapy with ethanol.

We report a case of successful percutaneous treatment of a chronic post-traumatic splenic pseudocyst using alcohol as the sclerosing agent. A 26-year-old man presented with a symptomatic cystic mass located in the spleen. Aspiration of 300 ml of fluid was only temporarily effective, and therefore a drainage catheter was placed 3 days later. After histopathologic and microbiologic exclusion of a malignant or infectious origin, local sclerotherapy with alcohol was performed because of recurrence after percutaneous drainage. This therapy was repeated six times within 2 weeks. Two weeks later, the remaining volume was determined to be 16 ml. Six months after treatment the cyst was no longer visible. To our knowledge this is the first case of a chronic post-traumatic splenic cyst treated with alcohol. Percutaneous sclerotherapy of a symptomatic post-traumatic splenic pseudocyst may be an alternative to surgical treatment.

Adult↗
PubMedDate not supplied

Signal, contrast, and resolution in optimized PD- and T2-weighted turbo SE images of the knee.

OBJECTIVE: Signal and contrast behavior, delineation of anatomical details, and flow artifacts were compared in dual echo SE and turbo SE (TSE) sequences. Results were correlated with theoretical aspects of the TSE technique. MATERIALS AND METHODS: A TSE sequence (TR = 3,500 ms, TEeff = 19, 93 ms, ETL = 3) and a conventional SE sequence (TR = 2,500 ms, TE = 20, 70 ms) were applied to 64 patients with knee injuries. Signal intensities of anatomical structures were measured in regions of interest. Contrast and edge sharpness of menisci and posterior cruciate ligament were evaluated by three independent observers. RESULTS: The TSE sequence yielded similar signal and contrast behavior compared with SE. Visual evaluation revealed nearly equivalent contrast and edge sharpness of menisci and posterior cruciate ligament in proton-density (PD)-weighted TSE images. Contrast and edge sharpness of menisci were significantly lower in T2-weighted TSE images. Reduced flow artifacts were found in PD- and especially in T2-weighted TSE images. Differences between both techniques are interpreted, taking into account influence of TEeff, ETL, k-space trajectory, magnetization transfer effects, and J-coupling. CONCLUSION: The TSE sequence yielded good image quality in PD-weighted, but slightly inferior quality in T2-weighted, images, reducing the time of acquisition by 50%.

Adult↗
PubMedDate not supplied

Spiral-CT in diagnosis of vascular involvement in pancreatic cancer.

BACKGROUND/AIMS: The purpose of this prospective study was to evaluate the efficacy of spiral-CT for the identification of portal venous, superior mesenteric artery and celiac trunk infiltration in the staging of pancreatic (n = 29) and periampullary (n = 6) cancers. MATERIALS AND METHODS: All patients were examined by contrast enhanced spiral-CT using a total volume of 240 ml contrast medium i.v. With a slice thickness of 5 mm and a table increment of 7 mm/sec a overlapping data set, representing a total volume of 21 cm, was covered. The images were reconstructed in 4 mm intervals. In 28 patients the spiral CT results were correlated with surgical findings. RESULTS: Regarding portal venous infiltration spiral-CT had a sensitivity of 91% (10/11), a specificity of 9.4% (16/17), a positive predictive value of 91% (10/11), a negative predictive value of 94% (16/17) and, an overall accuracy of 92.8% (26/28). Spiral CT correctly identified arterial involvement in 5 patients, and no false negative result compared to surgical findings was observed. CONCLUSIONS: These results indicate that spiral-CT reliably verifies occlusion, stenosis and encasement of the major peripancreactic vessels caused by pancreatic cancer.

Aged↗