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A Huber

Publications and source records attributed to A Huber.

At least 55 records · Page 3Linked to original sources
PubMed2001

Prospective detection of clinically relevant prostate cancer in the prostate specific antigen range 1 to 3 ng./ml. combined with free-to-total ratio 20% or less: the Aarau experience.

PURPOSE: Little is known about the incidence rate and clinical relevance of prostate cancer in a low prostate specific antigen (PSA) level. In a prospective PSA based screening study we investigated the incidence and clinicopathological features of prostate cancer that occurred within PSA range 1 to 3 ng./ml. when the free-to-total ratio was 0.20 or less. MATERIALS AND METHODS: Men participating in the Aarau, Switzerland, section of the European Randomized Study of Screening for Prostate Cancer between October 1998 and July 2000 were included in the study. As a side study, all men with PSA between 1 and 3 ng./ml. and free-to-total ratio 0.20 or less were invited to undergo further evaluation with ultrasound guided sextant prostate biopsy. RESULTS: Overall, 168 (7.8%) participants fulfilled inclusion criteria. A total of 158 (94%) patients underwent prostate biopsy, and prostate cancer was detected in 17 (10.8%). There were no statistically significant differences between prostate cancer and benign prostatic hyperplasia in regard to patient age (60.7 versus 59.8 years), prostate volume (23.9 versus 23.0 cc), PSA (1.98 versus 1.86 ng./ml.), free-to-total ratio (0.161 versus 0.160), PSA density (0.089 versus 0.076 ng./ml.) or PSA transition zone density (0.33 versus 0.24 ng./ml., respectively). Median Gleason score was 5 on prostate biopsy versus 6 on retropubic prostatectomy specimen. Of the 14 patients who underwent surgery there were positive lymph nodes in 1, stage pT3b Gleason 7 disease in 1, and pathologically organ confined Gleason 5 in 2, Gleason 6 in 5 and Gleason 7 in 5. Mean tumor volume was 1.01 cc (range 0.02 to 5.17). There were 2 (14.3%) insignificant (less than 0.2 cc, Gleason grade 3 or less), 1 (7.1%) minimal (less than 0.5cc, Gleason grade 3 or less) and 11 (78.6%) clinically relevant and potentially harmful cancers. CONCLUSIONS: There is a significant number of prostate cancer cases diagnosed at PSA as low as 1 to 3 ng./ml. A majority of these tumors are clinically significant. This free-to-total ratio range may be helpful for identifying prostate cancer. The "window of opportunity" for detection of curable cancer may change in populations with higher life expectancy towards lower PSA. Lack of specificity and characterization of tumor aggressiveness remains an unsolved issue for PSA.

Aged↗
PubMed2001

Modeling pesticide losses from diffuse sources in Germany.

A GIS-based model estimates the losses from diffuse sources in surface waters in Germany for 42 active ingredients applied to 11 field crops, vineyards and orchards. For the following pathways of entry: tile drainage, runoff and spray drift, the calculated mean pesticide input amounts to 1490 kg/year, 9060 kg/year and 3350 kg/year, respectively, in 1994. The model results are highly sensitive to the model parameters, primarily the chemical properties of the active ingredients. The modeled water inputs were compared with measured pesticide loads in smaller catchments and large river basins to validate model results. Both datasets agree as to the order of magnitude, nevertheless due to the scale of the study the results should be addressed mainly to comparative interpretations with the focus on the proportions between different active ingredients, soil regions, climates and application periods.

Agriculture↗
PubMed2000

Sensitivity of trypanosomatid protozoa to DFMO and metabolic turnover of ornithine decarboxylase.

alpha-Difluoromethylornithine (DFMO), the specific and irreversible inhibitor of ornithine decarboxylase (ODC), was able to induce the arrest of proliferation in Leishmania mexicana and ODC-transformed Trypanosoma cruzi cultures grown in a semi-defined medium essentially free of polyamines. Conversely, Crithidia fasciculata and Phytomonas 274 were not affected by the inhibitor. The drug-resistance of Crithidia and Phytomonas was neither caused by an impairment of DFMO uptake nor by a decrease of the enzyme affinity for the inhibitor. We were also able to rule out the possibility of ODC overexpression in the drug-tolerant parasites. The measurements of ODC metabolic turnover indicated that the enzymes from Crithidia and Phytomonas have a short half-life of 20-40 min, while ODC from Leishmania and transgenic Trypanosoma cruzi are rather stable with a half-life longer than 6 hours. Analyses of polyamine internal pools under different growth conditions have shown that DFMO was able to markedly decrease the levels of putrescine and spermidine in all parasites, but the depletion of spermidine was higher in trypanosomatids containing an ODC with slow turnover. Our results suggest that in these parasites cultivated in the presence of the drug, spermidine might decrease below critical levels needed to maintain trypanothione concentrations or other conditions essential for normal proliferation.

Animals↗
PubMed2000

Regulation of intracellular calcium by a signalling complex of IRAG, IP3 receptor and cGMP kinase Ibeta.

Calcium release from the endoplasmic reticulum controls a number of cellular processes, including proliferation and contraction of smooth muscle and other cells. Calcium release from inositol 1,4,5-trisphosphate (IP3)-sensitive stores is negatively regulated by binding of calmodulin to the IP3 receptor (IP3R) and the NO/cGMP/cGMP kinase I (cGKI) signalling pathway. Activation of cGKI decreases IP3-stimulated elevations in intracellular calcium, induces smooth muscle relaxation and contributes to the antiproliferative and pro-apoptotic effects of NO/cGMP. Here we show that, in microsomal smooth muscle membranes, cGKIbeta phosphorylated the IP3R and cGKIbeta, and a protein of relative molecular mass 125,000 which we now identify as the IP3R-associated cGMP kinase substrate (IRAG). These proteins were co-immunoprecipitated by antibodies directed against cGKI, IP3R or IRAG. IRAG was found in many tissues including aorta, trachea and uterus, and was localized perinuclearly after heterologous expression in COS-7 cells. Bradykinin-stimulated calcium release was not affected by the expression of either IRAG or cGKIbeta, which we tested in the absence and presence of cGMP. However, calcium release was inhibited after co-expression of IRAG and cGKIbeta in the presence of cGMP. These results identify IRAG as an essential NO/cGKI-dependent regulator of IP3-induced calcium release.

Amino Acid Sequence↗
PubMed2000

Cysteine-rich protein 2, a novel substrate for cGMP kinase I in enteric neurons and intestinal smooth muscle.

Nitric oxide/cGMP/cGMP kinase I (cGKI) signaling causes relaxation of intestinal smooth muscle. In the gastrointestinal tract substrates of cGKI have not been identified yet. In the present study a protein interacting with cGKIbeta has been isolated from a rat intestinal cDNA library using the yeast two-hybrid system. The protein was identified as cysteine-rich protein 2 (CRP2), recently cloned from rat brain (Okano, I., Yamamoto, T., Kaji, A., Kimura, T., Mizuno, K., and Nakamura, T. (1993) FEBS Lett. 333, 51-55). Recombinant CRP2 is specifically phosphorylated by cGKs but not by cAMP kinase in vitro. Co-transfection of CRP2 and cGKIbeta into COS cells confirmed the phosphorylation of CRP2 in vivo. Cyclic GMP kinase I phosphorylated CRP2 at Ser-104, because the mutation to Ala completely prevented the in vivo phosphorylation. Immunohistochemical analysis using confocal laser scan microscopy showed a co-localization of CRP2 and cGKI in the inner part of the circular muscle layer, in the muscularis mucosae, and in specific neurons of the myenteric and submucosal plexus. The co-localization together with the specific phosphorylation of CRP2 by cGKI in vitro and in vivo suggests that CRP2 is a novel substrate of cGKI in neurons and smooth muscle of the small intestine.

Amino Acid Sequence↗
PubMed2000

The visual G protein of fly photoreceptors interacts with the PDZ domain assembled INAD signaling complex via direct binding of activated Galpha(q) to phospholipase cbeta.

Visual transduction in the compound eye of flies is a well-established model system for the study of G protein-coupled transduction pathways. Pivotal components of this signaling pathway, including the principal light-activated Ca(2+) channel transient receptor potential, an eye-specific protein kinase C, and the norpA-encoded phospholipase Cbeta, are assembled into a supramolecular signaling complex by the modular PDZ domain protein INAD. We have used immunoprecipitation assays to study the interaction of the heterotrimeric visual G protein with this INAD signaling complex. Light-activated Galpha(q)- guanosine 5'-O-(thiotriphosphate) and AlF(4)(-)-activated Galpha(q), but not Gbetagamma, form a stable complex with the INAD signaling complex. This interaction requires the presence of norpA-encoded phospholipase Cbeta, indicating that phospholipase Cbeta is the target of activated Galpha(q). Our data establish that the INAD signaling complex is a light-activated target of the phototransduction pathway, with Galpha(q) forming a molecular on-off switch that shuttles the visual signal from activated rhodopsin to INAD-linked phospholipase Cbeta.

Animals↗
PubMed2000

Salvage surgery after failure of nonsurgical therapy for carcinoma of the larynx and hypopharynx.

BACKGROUND: For larynx preservation, radiotherapy is gaining popularity for primary treatment of laryngeal and hypopharyngeal cancer, reserving surgery for salvage. OBJECTIVE: To analyze the outcome of salvage surgery after failure of primary radiotherapy. DESIGN: Nine-year retrospective outcome analysis. SETTING: University referral center. PATIENTS: Fifty-four patients with squamous cell carcinoma of the larynx (n = 39) or hypopharynx (n = 15). RESULTS: For laryngeal cancer, mean interval from radiation to detection of recurrence was 14.5 months (range, 2-66 months). Twenty-three patients (59%) presented with a more advanced tumor stage after radiation than at the initial evaluation. Total laryngectomy was needed in 36 patients (92%). Disease-specific 5-year survival rate was 63%. Survival of patients with small recurrent tumors was statistically significantly better than those with advanced tumors (P =.004). For hypopharyngeal cancer, mean interval from radiation to detection of the recurrence was 10.6 months (range, 3-40 months). Total laryngopharyngectomy was needed in 8 of 9 patients with local recurrrence; neck dissection, in 6 patients with regional recurrence. Disease-specific 5-year survival rate was only 20%. Recurrent tumor and node stages did not influence the outcome. Patients with regional recurrences did no better than those with local ones. CONCLUSIONS: Salvage surgery in laryngeal cancer achieves good results, especially for small recurrences. Because of tumor progression, larynx preservation is seldom possible at the time of salvage. Salvage surgery in hypopharyngeal cancer shows poor survival regardless of tumor stage and despite radical surgical procedures, and can be recommended only for carefully selected patients. Arch Otolaryngol Head Neck Surg. 2000;126:1473-1477

Carcinoma, Squamous Cell↗
PubMed2000

[Myocardial perfusion at rest and during stress. MR signal characteristics of persistent and reversible myocardial ischemia].

AIM: Performance of combined rest/stress MR perfusion studies and the analysis of qualitative signal intensity parameters in comparison with 99mTc-SestaMIBI SPECT in patients with known coronary artery disease (CAD). METHODS: Sixteen patients with CAD underwent MR myocardial perfusion assessment at rest and after dipyridamole-induced hyperemia. Qualitative parameters (SI increase, SI upslope) of the SI time-curves were evaluated and characteristics of normal, reversible and persistent hypoperfused myocardium as assessed by 99mTc-SestaMIBI SPECT were compared. RESULTS: Compared with the rest values, normal myocardium showed a significant increase of the SI upslope during hyperemia (P < 0.001), whereas persistent (P = 0.07) and reversible (P = 0.15) hypo-perfusions showed only minor changes. SI increase over baseline also showed a significant increase only in normal myocardium (P < 0.001). At rest, reversible ischemic areas showed no significant differences from normal myocardium, whereas during hyperemia SI increase was significantly lower (P = 0.02). CONCLUSIONS: Qualitative SI parameters of a combined rest/stress MR myocardial perfusion study allow to differentiate normal from reversibly or persistently hypoperfused myocardium.

Adult↗
PubMed2000

[MR angiography of the supraaortic vessels].

PURPOSE: To compare high resolution contrast-enhanced MR angiography (MRA) and digital subtraction angiography (DSA) in the assessment of supraaortic vessel stenosis. METHODS: 14 patients with suspicion of cerebrovascular disease or upper limb ischemia underwent selective DSA and high resolution contrast enhanced MRA employing a new Panoramic-Array coil. Stenosis assessment in comparison to DSA followed NASCET criteria. Additionally signal-/noise ratios (SNR) were evaluated to assess contrast enhancement. RESULTS: Diagnostic image quality was achieved in all patients. Sensitivity and specificity for assessing high-grade stenosis of the supraaortic vessels were 100% and 96% respectively. In the assessment of high-grade common or internal carotid artery stenosis sensitivity and specificity was 100%. CONCLUSION: High resolution contrast enhanced supraaortic MRA combined with new coil systems allow for a reliable assessment of stenoses along the whole vessel course including the aortic arch. Previous stent procedures limit its use in postinterventional follow-up.

Adult↗
PubMed2000

Human glandular kallikrein as a tool to improve discrimination of poorly differentiated and non-organ-confined prostate cancer compared with prostate-specific antigen.

OBJECTIVES: Human glandular kallikrein (hK2) possesses 80% structure identity with prostate-specific antigen (PSA) and is secreted by identical prostate epithelial cells. Although increasing with pathologic stage, PSA is not clinically sufficient to predict histologic grade and pathologic stage of prostate cancer (PCa) in individual cases. To address this issue, serum hK2 in various PCa grades was investigated. METHODS: Sera from 122 consecutive patients with PCa, graded as well-differentiated (G1, n = 35); moderately differentiated (G2, n = 61), and poorly differentiated (G3, n = 26) PCa, was studied. In patients who underwent radical prostatectomy (n = 42), 24 had organ-confined (pT2a-b) and 18 extracapsular (pT3a or greater) disease. hK2 was measured by an indirect immunofluorometric assay with a functional sensitivity of 0.03 ng/mL. Total PSA (tPSA), free PSA (fPSA), and PSA bound to alpha(1)-antichymotrypsin (PSA-ACT) were also measured. Multivariate logistic regression analysis was used for evaluation of the best combinations of tumor markers. RESULTS: Median hK2 and tPSA increased twofold from G1 to G2 tumors (hK2 0.07 versus 0.14 ng/mL, P <0.002; tPSA 6.1 versus 12.1 ng/mL, P <0.0002). Between G2 and G3 tumors, hK2 increased threefold (0.14 versus 0.43 ng/mL, P <0.02), and tPSA showed no significant increase (12.1 versus 26.5 ng/mL, P <0.18). The f/t PSA ratio decreased between G1 and G2 cancers (0.15 vs. 010, P <0.001); no difference was found between G2 and G3 tumors (0.10 versus 0.11, P = 0.93). However, the hK2/fPSA ratio distinguished between G1 and G3 tumors and G2 and G3 tumors (0.085 [G1] and 0.11 [G2] versus 0.22 [G3], P <0.0002 and P <0.002, respectively). Using multivariate regression analysis, the fPSA/(tPSA x hK2) ratio differentiated G2 and G3 tumors (P <0.01). In the tPSA range of 3 to 15 ng/mL, hK2, the hK2/fPSA ratio, and the fPSA/(tPSA x hK2) ratio differentiated between the G1/G2 and G3 tumors, and tPSA, the f/t PSA ratio, and PSA-ACT did not. In radical prostatectomy cases, hK2 (0.06 versus 0. 156, P <0.005) and the fPSA/(tPSA x hK2) ratio (2.104 versus 0.828, P <0.005) discriminated between pT2a-b and pT3a or greater PCa. CONCLUSIONS: hK2 significantly improved the identification of poorly differentiated (G3) tumors compared with PSA. By multivariate logistic regression analysis, the hK2/fPSA and fPSA/(tPSA x hK2) ratios further improved the detection of PCa grade. This improvement was also seen with the intermediate range of tPSA. hK2 was also helpful in the prediction of organ-confined disease. Thus, hK2 may be a useful tool for more accurate prediction of tumor grade or stage and allow better clinical decision-making.

Aged↗
PubMed2000

The Calliphora rpa mutant lacks the PDZ domain-assembled INAD signalling complex.

The visual transduction cascade of fly photoreceptors is a G protein-coupled phospholipase C-signalling pathway which is assembled into a supramolecular signalling complex by the PDZ (postsynaptic density protein-95, discs large, Z0-1) domain protein INAD (inactivation no afterpotential D). The norpA-encoded phospholipase Cbeta, the light-activated transient receptor potential (TRP) Ca2+ channel and an eye-specific protein kinase C are bound to INAD and together form the core of the signalling complex. In the present study we show that the Calliphora rpa mutant, which has previously been hypothesized to represent an equivalent of Drosophila norpA mutants, has normal amounts of norpA mRNA but fails to express inaD mRNA. Electrophysiological recordings from the eyes of the rpa mutant reveal that the electroretinogram is reduced (about 12% of wild type) but not completely absent, and that it exhibits markedly prolonged deactivation kinetics. Furthermore, rpa mutants display a slow, light-dependent degeneration of the photoreceptor cells. With respect to the INAD signalling complex, the rpa mutant is similar to the Drosophila inaD null mutant: not only INAD itself, but also the other core components of the INAD signalling complex, are reduced or absent in photoreceptor membranes of rpa flies. Residual TRP is localized throughout the plasma membrane of the photoreceptor cell, rather than being restricted to the microvillar photoreceptor membrane. [35S]methionine-labelling of newly synthesized retinal proteins reveals that TRP is synthesized in the rpa mutant at wild-type level, but is transported to or incorporated into the microvillar photoreceptor membrane at a much lower rate. We thus suggest, that the formation of the INAD signalling complex is required for specifically targeting its components to the photoreceptor membrane.

Animals↗
PubMed2000

[Rehabilitation of homonymous hemianopsia].

BACKGROUND: Homonymous hemianopia, most often caused by cerebral arterial infarction, represents for the patient a severe handicap, whereby beside bumping into persons and objects disturbance of reading and writing are predominant. In the beginning the patients often are not aware of the hemianopia (anosognosia) or even completely deny it (hemi-neglect). For rehabilitation of homonymous hemianopia different successful methods are at disposal. METHODS: 1. Improvement of the patient's attention for the blind hemifield, 2. Enlargement of the saccadic search field. 3. Systematization of the search strategies, 4. Treatment of the hemianopic reading and writing disturbance, 5. Auxiliary optical measures. CONCLUSIONS: The rehabilitation of homonymous hemianopia with the described different methods is most successful and improves for the patient not only elementary and higher visual functions (visual exploration, reading and writing ability, parafoveal visual field, recognition of forms and colours), but may under favorable circumstances even restore partial or total working capacity.

Attention↗
PubMed2000

[Unstable pediatric femoral and forearm shaft fractures. Comparison between conservative treatment and stable intramedullary nailing].

Elastic intramedullary nailing represents a new surgical concept in the treatment of unstable shaft fractures in children. The present case control study wanted to examine the superiority of intramedullary nailing in comparison to conservative therapeutic concepts which had been applied so far. 13 children with forearm fractures who were treated initially by conservative measures were compared to 13 other children who received a primary intramedullary nailing. With femoral fractures, 12 children were included in each group. In each patient pair age, type and localisation of the fracture were comparable. During the observation period (until the termination of final therapeutic measures or until the third year after injury) we examined clinical variables and subjective findings. Both therapeutic concepts led to comparably good functional results. Also subjective judgement of the therapeutic success did not differ between groups. However, with intramedullary nailing of shaft fractures of the femur the mean hospital length of stay (7.0 +/- 3.5 days) was significantly shorter than with initial conservative treatment (36.5 +/- 2.2 days, P < 0.05). Irrespective of the localisation of the fracture intramedullary nailing required significantly less x-ray examinations during the observation period. These results suggest intramedullary nailing to be the procedure of choice to treat unstable forearm and femoral fractures in children.

Adolescent↗
PubMed2000

Gastroesophageal reflux and diaphragmatic motility after repair of congenital diaphragmatic hernia.

At the Department of Pediatric Surgery in Graz, 31 boys and 23 girls were operated on for congenital diaphragmatic hernia (CDH) from 1978 to 1994. In 49 patients the defect was on the left, in five on the right side. In 46 cases, the hernia was diagnosed within the first week of life; in eight children at a later date. 19 children (35%) died. 25 of the 35 survivors (71%) came to a follow-up examination on average 9.4 (1-17) years after the operation. 24 h pH-monitoring or manometry and Upper G.I. series revealed pathological gastroesophageal reflux (GER) in 16 patients. Nine children were treated conservatively; in seven patients an antireflux procedure was performed. A thoracic position of the stomach or left liver lobe, presence of a hernial sac, gestational age, prenatal diagnosis, use of a patch or severity of lung hypoplasia did not significantly influence the incidence of GER. In three patients, a hiatal hernia was found. The motility of the diaphragm was documented with M-mode sonography (n = 18); a restricted motility could be demonstrated in five patients. GER is very common in patients after repair of CDH. We recommend long-term follow-up with special interest in respect of GER.

Child↗
PubMed2000

Three new NifA-regulated genes in the Bradyrhizobium japonicum symbiotic gene region discovered by competitive DNA-RNA hybridization.

The so-called symbiotic region of the Bradyrhizobium japonicum chromosome (C. Kündig, H. Hennecke, and M. Göttfert, J. Bacteriol. 175:613-622, 1993) was screened for the presence of genes controlled by the nitrogen fixation regulatory protein NifA. Southern blots of restriction enzyme-digested cosmids that represent an ordered, overlapping library of the symbiotic region were competitively hybridized with in vitro-labeled RNA from anaerobically grown wild-type cells and an excess of RNA isolated either from anaerobically grown nifA and rpoN mutant cells or from aerobically grown wild-type cells. In addition to the previously characterized nif and fix gene clusters, we identified three new NifA-regulated genes that were named nrgA, nrgB, and nrgC (nrg stands for NifA-regulated gene). The latter two probably form an operon, nrgBC. The proteins encoded by nrgC and nrgA exhibited amino acid sequence similarity to bacterial hydroxylases and N-acetyltransferases, respectively. The product of nrgB showed no significant similarity to any protein with a database entry. Primer extension experiments and expression studies with translational lacZ fusions revealed the presence of a functional -24/-12-type promoter upstream of nrgA and nrgBC and proved the NifA- and RpoN (sigma(54))-dependent transcription of the respective genes. Null mutations introduced into nrgA and nrgBC resulted in mutant strains that exhibited wild-type-like symbiotic properties, including nitrogen fixation, when tested on soybean, cowpea, or mung bean host plants. Thus, the discovery of nrgA and nrgBC further emphasizes the previously suggested role of NifA as an activator of anaerobically induced genes other than the classical nitrogen fixation genes.

Amino Acid Sequence↗
PubMed2000

Pulmonary embolism: comprehensive diagnosis by using electron-beam CT for detection of emboli and assessment of pulmonary blood flow.

PURPOSE: To comprehensively assess thoracic anatomy and pulmonary microcirculation in pulmonary embolism by using computed tomographic (CT) angiography of the pulmonary arteries combined with functional CT imaging of blood flow. MATERIALS AND METHODS: Twenty-two patients suspected of having acute pulmonary embolism underwent contrast material-enhanced thin-section electron-beam CT angiography of the pulmonary arteries. In addition, in each patient, a dynamic multisection blood flow CT study was performed on a 7.6-cm lung volume with electrocardiographic gating. Pulmonary blood flow was calculated, and perfusion parameters were visualized on color-coded maps. The color-coded maps and CT angiograms were independently evaluated, segment by segment, by two readers for perfusion deficits and the presence of clots, respectively. The results were compared. RESULTS: Mean pulmonary blood flow was 0.63 mL/min/mL in the occluded segments versus 2.27 mL/min/mL in the nonoccluded segments (P: =.001). The sensitivity and specificity of perfusion maps for the presence of segmental pulmonary embolism compared with those of CT angiography were 75.4% and 82.3%, respectively, with positive and negative predictive values of 79.6% and 84.7%, respectively. The false-negative findings were caused mainly by partial occlusion of vessels. In eight patients, a substantial alternative or additional pathologic entity was diagnosed. CONCLUSION: By combining CT angiography and dynamic CT imaging, a comprehensive and noninvasive diagnosis of thoracic structure and function is feasible with a single modality.

Acute Disease↗
PubMed2000

Dynamic contrast-enhanced MR angiography from the distal aorta to the ankle joint with a step-by-step technique.

OBJECTIVE: The aim of this study was to visualize the arteries from the distal aorta to the ankle joint and to determine the accuracy of MR angiography for detecting stenoses and occlusions. SUBJECTS AND METHODS: Twenty-four patients with peripheral arterial occlusive disease underwent digital subtraction angiography and were examined on a 1.5-T MR scanner. The transit time for contrast material was determined with a test bolus injection. A T1-weighted three-dimensional gradient-echo sequence with short TR and TE was used for a dynamic measurement at the level of the iliac arteries, the upper leg, and the lower leg arteries. For each level a single dose of gadolinium was injected into an antecubital vein with an MR power injector. Maximal-intensity-projection reconstructions were calculated after subtraction of the first measurement at each level. Two experienced MR radiologists who were unaware of the digital subtraction angiography results interactively evaluated both the MIP reconstructions and the single slices on a workstation, first independently and then in a consensus interpretation. RESULTS: With digital subtraction angiography, 80 hemodynamically significant stenoses and 39 occlusions were detected. For the stenoses and occlusions, a sensitivity of 100% was found for MR angiography. The specificity for the assessment of stenoses and occlusions was 98% and 94%, respectively, for the iliac arteries; 98% and 94%, respectively, for the upper leg arteries; and 94% and 95%, respectively, for the lower leg arteries. Most false-positive findings of occlusion were due to metal stents present in the iliac (n = 3) and upper leg (n = 4) arteries. CONCLUSION: The MR imaging technique that we used revealed the arteries from the distal aorta to the ankle and proved to be reliable at showing arterial stenoses and occlusions.

Aged↗