Hartmut Stützer

University of Bonn - Medical Center, Bonn, North Rhine-Westphalia, Germany

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Publications (36)114.11 Total impact

  • [show abstract] [hide abstract]
    ABSTRACT: Background: Short-acting opioids like remifentanil are suspected of an increased risk for tolerance, withdrawal and opioid-induced hyperalgesia (OIH). These potential adverse effects have never been investigated in neonates. Objectives: To compare remifentanil and fentanyl concerning the incidence of tolerance, withdrawal and OIH. Methods: 23 mechanically ventilated infants received up to 96 h either a remifentanil- or fentanyl-based analgesia and sedation regimen with low-dose midazolam. We compared the required opioid doses and the number of opioid dose adjustments. Following extubation, withdrawal symptoms were assessed by a modification of the Finnegan score. OIH was evaluated by the CHIPPS scale and by testing the threshold of the flexion withdrawal reflex with calibrated von Frey filaments. Results: Remifentanil had to be increased by 24% and fentanyl by 47% to keep the infants adequately sedated during mechanical ventilation. Following extubation, infants revealed no pronounced opioid withdrawal and low average Finnegan scores in both groups. Only 1 infant of the fentanyl group and 1 infant of the remifentanil group required methadone for treatment of withdrawal symptoms. Infants also revealed no signs of OIH and low CHIPPS scores in both groups. The median threshold of the flexion withdrawal reflex was 4.5 g (IQR = 2.3) in the fentanyl group and 2.7 g (IQR = 3.3) in the remifentanil group (p = 0.312), which is within the physiologic range of healthy infants. Conclusions: Remifentanil does not seem to be associated with an increased risk for tolerance, withdrawal or OIH.
    Neonatology 04/2013; 104(1):34-41. · 2.57 Impact Factor
  • B Kühne, H Stützer, B Roth, L Welzing
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    ABSTRACT: The idea that preterm and term infants are capable of experiencing pain is now widely accepted. However, there is still insufficient knowledge how pain perception develops throughout infancy. A promising approach to quantify the level of spinal excitability in infants is to measure cutaneous sensitivity by the flexion withdrawal reflex (WR). In our study we wanted to test how the threshold of the WR develops in healthy infants during the first year of life. Furthermore, we aimed to analyse the impact of the state of consciousness on the reflex threshold. In 44 healthy infants we tested the threshold of the WR with calibrated von-Frey-Filaments at the age of 3 days as well as with 4, 12, 26 and 52 weeks. To analyse the influence of the state of consciousness on the reflex threshold, we documented at 12, 26 and 52 weeks whether the infants were quietly awake or lightly asleep during testing. The median threshold of the WR increased during the first year of life from 1.2 g up to 4.6 g at the age of 1 year. At 12, 26 and 52 weeks we found significantly lower thresholds in sleeping infants compared to infants being awake (p=0.004, p<0.001 and p=0.086, respectively). The threshold of the flexion withdrawal reflex increases during infancy, probably reflecting neuronal maturation processes in the first year of life. Besides postnatal age, the threshold of the WR also depends on the state of consciousness. Therefore, future studies about the WR should consider postnatal age as well as the state of consciousness.
    Klinische Pädiatrie 04/2012; 224(5):291-5. · 1.90 Impact Factor
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    ABSTRACT: Common opioids for analgesia and sedation of mechanically ventilated infants may tend to accumulate and cause prolonged sedation with an unpredictable extubation time. Remifentanil is a promising option due to its unique pharmacokinetic properties, which seem to be valid in adults as well as in infants. In this double-blind, randomized, controlled trial mechanically ventilated neonates and young infants (<60 days) received either a remifentanil or fentanyl-based analgesia and sedation regimen with low dose midazolam. The primary endpoint of the trial was the extubation time following discontinuation of the opioid infusion. Secondary endpoints included efficacy and safety aspects. Between November 2006 and March 2010, we screened 431 mechanically ventilated infants for eligibility. The intention to treat group included 23 infants who were assigned to receive either remifentanil (n = 11) or fentanyl (n = 12). Although this was designed as a pilot study, median extubation time was significantly shorter in the remifentanil group (80.0 min, IQR = 15.0-165.0) compared to the fentanyl group (782.5 min, IQR = 250.8-1,875.0) (p = 0.005). Remifentanil and fentanyl provided comparable efficacy with more than two-thirds of the measurements indicating optimal analgesia and sedation (66.4 and 70.2 %, respectively; p = 0.743). Overall, both groups had good hemodynamic stability and a comparably low incidence of adverse events. As neonates and young infants have a decreased metabolism of common opioids like fentanyl and are more prone to respiratory depression, remifentanil could be the ideal opioid for analgesia and sedation of mechanically ventilated infants.
    European Journal of Intensive Care Medicine 03/2012; 38(6):1017-24. · 5.17 Impact Factor
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    ABSTRACT: To compare the detection of microcalcifications on mammograms of an anthropomorphic breast phantom acquired by a direct digital flat-panel detector mammography system (FPM) versus a stereotactic breast biopsy system utilizing CCD (charge-coupled device) technology with either a 1024 or 512 acquisition matrix (1024 CCD and 512 CCD). Randomly distributed silica beads (diameter 100-1400 μm) and anthropomorphic scatter bodies were applied to 48 transparent films. The test specimens were radiographed on a direct digital FPM and by the indirect 1024 CCD and 512 CCD techniques. Four radiologists rated the monitor-displayed images independently of each other in random order. The rate of correct positive readings for the "number of detectable microcalcifications" for silica beads of 100-199 μm in diameter was 54.2%, 50.0% and 45.8% by FPM, 1024 CCD and 512 CCD, respectively. The inter-rater variability was most pronounced for silica beads of 100-199 μm in diameter. The greatest agreement with the gold standard was observed for beads >400 μm in diameter across all methods. Stereotactic spot images taken by 1024 matrix CCD technique are diagnostically equivalent to direct digital flat-panel mammograms for visualizing simulated microcalcifications >400 μm in diameter.
    International journal of breast cancer. 01/2011; 2011:701054.
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    ABSTRACT: To examine in vitro whether an assessment of flow in normal and obstructed vessels is essentially possible using modern multislice CT-scanners. An experimental model allowed known stenoses to be perfused at defined flow rates. Aorta and coronary arteries were simulated by silicone tubes. A pulsatile pump was used to perfuse water through the system with intermittent injection of a bolus of radio-opaque contrast agent. CT-measurements were carried out with slice orientation perpendicular to the tubes. 50-90% concentric stenoses were examined 5 times at 4 different stenosis slice distances. A mathematical algorithm calculated the temporal density changes within a ROI in the tube cross-sections. Quantitative assessment of the data simultaneously acquired with the 16-slice system for the "coronary" and "aortal" time-density curves showed that the model allowed for exclusion of a ≥ 80% stenosis grade with a 99% probability when the slopes of the density increase quotient was > 0.79; a stenosis grade of ≥ 90% could be excluded when the slopes of the density increase quotient was > 0.52. A Quotient > 0.94 for "peak density" was associated with a 99% probability of a stenosis grade ≥ 70%. The 64-slice system allowed stenosis grades of ≥ 80% to be discriminated from lower grades. The general feasibility of the in vitro approach was verified in an in vivo model. The spatial, contrast and temporal resolution of CT scanners with at least 16 detector rows enables qualitative and semiquantitative assessment of stenotic changes in flow.
    The international journal of cardiovascular imaging 10/2010; 27(6):795-804. · 2.15 Impact Factor
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    ABSTRACT: When decompression of the lumbar spinal canal is performed, segmental stability might be affected. Exactly which anatomical structures can thereby be resected without interfering with stability, and when, respectively how, additional stabilization is essential, has not been adequately investigated so far. The present investigation describes kinetic changes in a surgically treated motion segment as well as in its adjacent segments. Segmental biomechanical examination of nine human lumbar cadaver spines (L1 to L5) was performed without preload in a spine-testing apparatus by means of a precise, ultrasound-guided measuring system. Thus, samples consisting of four free motion segments were made available. Besides measurements in the native (untreated) spine specimen further measurements were done after progressive resection of dorsal elements like lig. flavum, hemilaminectomy, laminectomy and facetectomy. The segment was then stabilised by means of a rigid system (ART((R))) and by means of a dynamic, transpedicularly fixed system (Dynesys((R))). For the analysis, range of motion (ROM) values and separately viewed data of the respective direction of motion were considered in equal measure. A very high reproducibility of the individual measurements could be verified. In the sagittal and frontal plane, flavectomy and hemilaminectomy did not achieve any relevant change in the ROM in both directions. This applies to the segment operated on as well as to the adjacent segments examined. Resection of the facet likewise does not lead to any distinct increase of mobility in the operated segment as far as flexion and right/left bending is concerned. In extension a striking increase in mobility of more than 1degree compared to the native value can be perceived in the operated segment. Stabilization with the rigid and dynamic system effect an almost equal reduction of flexion/extension and right/left bending. In the adjacent segments, a slightly higher mobility is to be noted for rigid stabilization than for dynamic stabilisation. A linear regression analysis shows that in flexion/extension monosegmental rigid stabilisation is compensated predominantly in the first cranial adjacent segment. In case of a dynamic stabilisation the compensation is distributed among the first and second cranial, and by 20% in the caudal adjacent segment. Monosegmental decompression of the lumbar spinal canal does not essentially destabilise the motion segment during in vitro conditions. Regarding rigid or dynamic stabilisation, the ROM does not differ within the operated segment, but the distribution of the compensatory movement is different.
    Archives of Orthopaedic and Trauma Surgery 11/2009; 130(2):285-92. · 1.36 Impact Factor
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    ABSTRACT: Increasingly frequent applications of opioid analgesics in neonatal intensive care require the evaluation of efficacy and side effects. Mechanically ventilated term neonates were consecutively enrolled. In a double-blind randomized trial 20 newborns received a continuous intravenous infusion of fentanyl (n=10) or sufentanil (n=10) in an assumed equipotent dose of 7:1. The analgesic dose was individually adjusted according to sedation scores. The period between cessation of analgesic medication and successful extubation (weaning time), adverse drug effects and urinary cortisol concentrations were evaluated. No significant difference of weaning time was seen between fentanyl and sufentanil group (mean weaning time (+/-SD) of fentanyl group 520+/-381 min, median 380 min; sufentanil group 585+/-531 min, median 405 min, p=0.78, 2-tailed U-Test, Mann and Whitney). The mean opioid dose resulted in a 10:1 ratio (fentanyl 4.11 microg/(kg x h) vs sufentanil 0.41 microg/(kg x h)). We found no marked differences in sedation levels, blood pressure, heart rate, oxygenation index, co-medication or urinary cortisol levels. In both groups similar adverse effects were assessed including respiratory depression, mild withdrawal symptoms or decrease of gastrointestinal motility. In our study sufentanil did not reduce the weaning period in ventilated term neonates when compared to fentanyl. The equipotent dose ratio for fentanyl/sufentanil was 10:1. According to sedation scores both substances provided effective pain and stress protection.
    Klinische Pädiatrie 10/2009; 222(2):62-6. · 1.90 Impact Factor
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    ABSTRACT: Neurogenic intermittent claudication, caused by lumbar spinal stenosis (LSS), usually occurs after the age of 50 and is one of the most common degenerative spinal diseases in the elderly. Among patients over the age of 65 with LSS, open decompression is the most frequently performed spinal operation. The recently introduced interspinous spacers are a new alternative under discussion. In this retrospective study, we reviewed medical records and radiographs of patients with LSS and NIC treated from June 2003 to June 2007. All included patients (n = 129) were treated with interspinous implants (X Stop Wallis, or Diam). Evaluations of pain, using a visual analog scale (VAS), and radiographic signs, using two-plane X-rays of the lumbar spine, were performed preoperatively (preop), postoperatively (postop) and after discharge (FU 2-3). Gender ratio (m:w) was 1.1:1. Mean age of the patients was 60.8 +/- 16.3 years. Foraminal height, foraminal width, foraminal cross-sectional area, intervertebral angle, as well as anterior and posterior disc height changed significantly (P < 0.0001) after implantation of the interspinous device. Postoperatively, symptom relief (VAS) was significant (P < 0.0001). The X Stop implant improved (in some cases significantly) the radiographic parameters of foraminal height, width, and cross-sectional area, more than the Diam and Wallis implants; however, there was no significant difference among the three regarding symptom relief. FU 1 was on average 202.3 +/- 231.9 and FU 2 527.2 +/- 377.0 days postoperatively. During FU, the radiological improvements seemed to revert toward initial values. Pain (VAS) did not increase despite this "loss of correction." There was no correlation between age and symptom improvement. There was only very weak correlation between the magnitude of radiographic improvement and the extent of pain relief (VAS). The interspinous implant did not worsen low-grade spondylolisthesis. Provided there is a strict indication and fusion is not required, implantation of an interspinous spacer is a good alternative to treat LSS. The interspinous implant offers significant, longlasting symptom control, even if initially significant radiological changes seem to revert toward the initial values ("loss of correction").
    European Spine Journal 07/2009; 18(10):1494-503. · 2.13 Impact Factor
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    ABSTRACT: Retrospective analysis of therapy results in patients with stage I-II and limited stage III nodal low-grade non-Hodgkin's lymphoma (NHL). The present retrospective study covers 65 patients treated between 1988 and 2006 at the Department of Radiation Oncology, University of Cologne, Germany. 50 patients were treated with radiotherapy alone (EF [extended field]: n = 35, IF/REG [involved field/regional field]: n = 9, TNI/TLI [total nodal/total lymphatic]: n = 6), 15 patients additionally received chemotherapy. Median age was 58 years. 58 patients presented with centroblastic-centrocytic or follicular lymphomas, seven patients had centrocytic lymphomas. Apart from overall and relapse-free survival, relapse patterns were examined and the impacts of patient characteristics and therapy modalities were analyzed. After a median follow-up of 9.1 years, overall 5-year and 10-year survival was 86% and 55%, relapse-free survival was 55% and 37%, respectively. Relapses occurred in 28 patients during the observation period. Overall survival was favorably influenced by low patient age (p = 0.037), centroblastic-centrocytic/follicular histology (p = 0.006), and early disease stage (p = 0.045). Favorable prognostic factors for relapse-free survival were low patient age (p = 0.035) and centroblastic-centrocytic/follicular histology (p = 0.001). Radiotherapy of early-stage low-grade NHL is a curative therapy option, particularly in younger patients and patients with follicular histology. Relapse analysis confirmed the benefits of total nodal or total lymphatic irradiation, although the small number of patients needs to be considered.
    Strahlentherapie und Onkologie 06/2009; 185(5):288-95. · 4.16 Impact Factor
  • Strahlentherapie Und Onkologie - STRAHLENTHER ONKOL. 01/2009; 185(5):288-295.
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    ABSTRACT: We assess whether negative findings on computed tomography (CT), magnetic resonance imaging (MRI), and/or 18F-fluorodeoxyglucose positron emission tomography (18FDG-PET) may contribute to the decision-making process of elective neck dissection (eND) in patients with squamous cell carcinoma of the oral cavity or the oropharynx (oSCC) staged cT1-T2 cN0 cM0. We interpreted CT, MRI, and 18FDG-PET images separately, after combining the data of CT with those of 18FDG-PET and the data of MRI with those of 18FDG-PET. Each set of results was then compared with the histopathologic results of ipsilateral or bilateral eND in a prospective, blinded study. The histopathologic examination of 594 lymph nodes revealed 4 metastases less than 4 mm in diameter and 3 micrometastases (less than 2 mm) in 6 of 17 patients. On CT, MRI, and 18FDG-PET, respectively, 5, 5, and 0 cases were true-malignant (true positives) and 4, 10, and 1 cases were false-malignant (false positives). The accuracy was not enhanced by fusing CT with 18FDG-PET or MRI with 18FDG-PET. The detectability threshold of occult metastases appears to be below the spatial and contrast resolution of CT, MRI, and 18FDG-PET. The decision for eND in patients with cT1-T2 cN0 cM0 oSCC cannot be based upon cross-sectional imaging at the resolutions currently available.
    The Annals of otology, rhinology, and laryngology 12/2008; 117(11):854-63. · 1.21 Impact Factor
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    ABSTRACT: The objective of our study was to compare the detectability and distinguishability of simulated soft-tissue opacities of 50 variants of an anthropomorphic breast phantom in mammograms acquired with a digital direct flat-panel detector versus an analog system; we also compared the image settings "analog film," "digital film," and "digital monitor." The studies were performed on digital (Lorad Selenia) and analog (Mammomat 3) mammography systems. Four hundred fifty silicone cubes devised with different randomly distributed columns, holes, or both columns and holes (diameter, 3-7 mm; height, 0.5-4.0 mm) were used as test bodies. One experimental series was performed with a silicone scatter body and one with a silicone and an anthropomorphic ground-meat scatter body. All x-rays were obtained at identical settings and exposures. Four radiologists rated the films and monitor-displayed images independently of each other in randomized order on a standardized electronic questionnaire. The digital monitor technique generally scored better than digital film viewing and analog readings. The McNemar test for multiple paired comparisons mostly yielded a p value of < 0.0005. The smallest volume category counted as the most valid test scenario for all raters, where the percentage of correct positive findings ranged between 30% and 58% (analog technique), 43% and 68% (digital film viewing), and 55% and 66% (monitor viewing). The corresponding accuracy rates were 77-93%, 75-95%, and 81-85%, respectively, with kappa values of 0.2-0.5 (analog) and 0.3-0.6 (digital) for comparing the gold standard with raters' evaluations. Digital flat-panel mammography is superior to the analog screen-film method for the detection of simulated opacities.
    American Journal of Roentgenology 10/2008; 191(3):W80-8. · 2.90 Impact Factor
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    ABSTRACT: To evaluate whether the experience with a method to administer surfactant during spontaneous breathing with nasal continuous positive airway pressure (nCPAP) as primary respiratory support in infants with respiratory distress syndrome (RDS) influences the frequency of its use and affects the outcome of patients. All inborn extremely low birthweight (ELBW) infants treated after introduction of the method were retrospectively studied (n=196). The entire observational period was divided into four periods (periods 1-4) and compared with a control period (period 0) (n=51). Primary respiratory support, demographics, prenatal risks and outcomes were compared. There were no changes in demographics or prenatal risks over time. The choice of nCPAP as initial airway management significantly increased from 69% to 91% and for nCPAP with surfactant from 75% to 86%. The rate of nCPAP failure decreased from 46% to 25%. Survival increased significantly between periods 0 and 1 from 76% to 90% and survival without bronchopulmonary dysplasia (BPD) rose from 65% to 80%. No changes in nonpulmonary outcomes were observed. The success of nCPAP increased with increasing use of nCPAP with surfactant. Simultaneously, mortality decreased without deterioration of other outcomes indicating that the use of surfactant in spontaneous breathing with nCPAP could be beneficial.
    Acta Paediatrica 04/2008; 97(3):293-8. · 1.97 Impact Factor
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    ABSTRACT: Bone tumours are comparatively rare tumours and delays in diagnosis and treatment are common. The purpose of this study was to analyse sociodemographic risk factors for bone tumour patients in order to identify those at risk of prolonged patients delay (time span from first symptoms to consultation), professional delay (from consultation to treatment) or symptom interval (from first symptoms to treatment). Understanding these relationships might enable us to shorten time to diagnosis and therapy. We carried out a retrospective analysis of 265 patients with bone tumours documenting sociodemographic factors, patient delay, professional delay and symptom interval. A multivariate explorative Cox model was performed for each delay. Female gender was associated with a prolonged patient delay. Age under 30 years and rural living predisposes to a prolonged professional delay and symptom interval. Early diagnosis and prompt treatment are required for successful management of most bone tumour patients. We succeeded in identifying the histology independent risk factors of age under 30 years and rural habitation for treatment delay in bone tumour patients. Knowing about the existence of these risk groups age under 30 years and female gender could help the physician to diagnose bone tumours earlier. The causes for the treatment delays of patients living in a rural area have to be investigated further. If the delay initiates in the lower education of rural general physicians, further training about bone tumours might advance early detection. Hence the outcome of patients with bone tumours could be improved.
    BMC Cancer 02/2008; 8:22. · 3.33 Impact Factor
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    ABSTRACT: Molecular prognostic indicators for oropharyngeal squamous cell carcinoma (OSCC), including HPV-DNA detection, epidermal growth factor receptor (EGFR) and p16 expression, have been suggested in the literature, but none of these are currently used in clinical practice. To compare these predictors, 106 newly diagnosed OSCC for the presence of HPV-DNA and expression of p16 and EGFR were analyzed. The 5-year disease-free survival (DFS) and overall survival (OS) were calculated in relation to these markers and a multivariate Cox analysis was performed. Twenty-eight percent of the cases contained oncogenic HPV-DNA and 30% were positive for p16. The p16 expression was highly correlated with the presence of HPV-DNA (p < 0.001). Univariate analysis of the 5-year DFS revealed a significantly better outcome for patients with p16-positive tumors (84% vs. 49%, p = 0.009). EGFR-negative tumors showed a tendency toward a better prognosis in DFS (74% vs. 47%, p = 0.084) and OS (70% vs. 45%, p = 0.100). Remarkable and highly significant was the combination of p16 and EGFR expression status, leading to 5-year DFS of 93% for p16+/EGFR- tumors vs. 39% for p16-/EGFR+ tumors (p = 0.003) and to a 5-year OS of 79% vs. 38%, respectively (p = 0.010). In multivariate analysis p16 remained a highly significant prognostic marker for DFS (p = 0.030) showing a 7.5-fold increased risk for relapse in patients with p16-negative tumors. Our data indicate that p16 expression is the most reliable prognostic marker for OSCC and further might be a surrogate marker for HPV-positive OSCC. HPV+/p16+ tumors tended to have decreased EGFR expression, but using both immunohistological markers has significant prognostic implications.
    International Journal of Cancer 05/2007; 120(8):1731-8. · 6.20 Impact Factor
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    ABSTRACT: To assess the single and multimodal treatment results and prognostic factors for sinonasal carcinoma. Overall survival (OS), disease-specific survival (DSS), local control (LC), and disease-free survival (DFS) in 229 patients with sinonasal carcinoma treated from 1967 to 2003 were calculated. Prognostic factors were univariately and multivariately analyzed. The median follow-up period for survivors was 126 months. 32% of the patients were operated only, 47% underwent multimodal therapy, and 20% were treated without operation. The 5-year OS rate was 41%, and the DSS rate was 51%. The LC rate was 64%, and the DFS rate was 34%. Prognostic for DSS were M status (p<0.001), UICC stage (p<0.001), T classification (p=0.001), N status (p=0.002), intracranial tumor infiltration (p=0.008), infiltration of the pterygopalatine fossa (p=0.02), infiltration of the skull base (p=0.021), infiltration of the orbita (p=0.041), and the type of therapy (p<0.001): The 5-year DSS rate was 63% for patients operated only, 56% for all operated patients, 46% for patients undergoing surgery and radiotherapy, but only 21% for patients treated with radiotherapy+/-chemotherapy. Multivariate analysis revealed that T classification (p=0.042), N classification (p=0.035), M classification (p=0.007), UICC stage (p=0.038), and type of therapy (p=0.038) were independent prognostic factors for DSS. Radical surgery is recommended for stage I/II sinonasal carcinomas. Stage III/IV carcinomas still have a poor prognosis, but multimodal treatment seems to favor the outcome.
    European Journal of Surgical Oncology 04/2007; 33(2):222-8. · 2.61 Impact Factor
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    ABSTRACT: The objective of our study was to compare the detection and distinguishability of microcalcifications on mammograms obtained with a digital direct flat-panel detector versus an analog system using an anthropomorphic breast phantom. Studies were performed with a digital mammography system (Selenia) and an analog mammography system (Mammomat 3). Sixty-five transparent films were used as test specimens. Randomly distributed round and heterogeneous silicate particles (diameter, 100-1,400 microm) and an anthropomorphic scatter body were applied to the films. All radiographs were taken at identical settings and exposures. Six radiologists rated the films and monitor-displayed images independently of each other in random order on a standardized electronic questionnaire. Interpretations based on monitor reading produced superior results over those based on digital image reading and analog film reading. In 41.1% (95% CI, 38.7-43.5%) of all the monitor readings, 20.2% (18.2-22.2%) of all digital images, and 19.6% (17.6-21.6%) of all analog films, the number of detectable microcalcifications agreed with the gold standard method. The diameter of visible microcalcifications was interpreted correctly in 35.6% (33.2-38.0%) of monitor readings, 19.0% (17.1-21.0%) of digital images, and 21.0% (18.9-23.0%) of analog films; and microcalcification shape was interpreted correctly in 53.8% (51.4-56.3%) of monitor readings, 28.2% (26.0-30.4%) of digital images, and 28.3% (26.0-30.5%) of analog films. Microcalcification number and size were underestimated more frequently than overestimated. Regardless of display medium, accuracy increased proportionately with the diameter of the simulated microcalcifications for all evaluation variables. Digital flat-panel mammography is superior to the analog screen-film method for the detection and morphologic characterization of microcalcifications larger than 200 microm in diameter when the display medium is a monitor.
    American Journal of Roentgenology 03/2007; 188(2):399-407. · 2.90 Impact Factor
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    ABSTRACT: Neonatal reference values of gallbladder size have been assessed in healthy newborns with enteral feeding regimen. Their applicability to critically ill patients under total parenteral nutrition (TPN) remains to be questioned. Our aim was to evaluate the impact of short-term TPN versus enteral nutrition (EN), gender and birth weight on neonatal gallbladder volume. A prospective pilot study was initiated with a single sonographic investigator blinded towards feeding regimen. In total, 61 neonates (33 males, 28 females) were consecutively enrolled on the intensive care unit; 31 newborns were examined both under TPN and bolus EN (breast milk/formula). Patients with malformations of the biliary tract were excluded. Prior to ultrasound examinations, a minimum fasting period of 2 h was maintained. Sonographic measurements of gallbladder length, depth and width were performed to calculate gallbladder volume using the ellipsoid formula. Neonatal gallbladder volume differed significantly between TPN and EN (p < 0.001). Using TPN, range of gallbladder length, width and volume exceeded reference values. Birth weight was weakly correlated with gallbladder volume (correlation index 0.3776, p = 0.01). We found no gender-related differences. Neonatal gallbladder volume under TPN was significantly larger compared to EN. Using TPN, gallbladder dimensions exceeded reference values without causing clinical complications. The benign course of gallbladder enlargement required no specific medication or surgical treatment.
    Neonatology 02/2007; 92(3):201-4. · 2.57 Impact Factor
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    ABSTRACT: In an effort to minimise the stress and pain of mechanically ventilated neonates, the application of opioids has increased markedly. Abdominal adverse effects of opioid analgesics are constipation and increased pressure in the biliary system. Our aim was to evaluate the impact of continuous intravenous infusion of fentanyl on the volume of the neonatal gallbladder and to assess potential gastrointestinal side effects. We prospectively matched pairs of 40 mechanically ventilated neonates (28-42 gestational weeks) under total parenteral nutrition and midazolam sedation. One group (20 patients) received continuous fentanyl infusions (dose 0.5-2 microg kg(-1) h(-1)) the other group (20 patients) served as controls. Sonographic measurements of gallbladder length, depth and width were performed to calculate gallbladder volume using the ellipsoid method. Repeated ultrasound images, date of meconium release and serum bilirubin levels were documented. Fentanyl application was not associated with gallbladder sludge/stones, gallbladder hydrops, hyperbilirubinemia or prolonged meconium release. Neonatal gallbladder length, width and volume did not differ significantly (data expressed as mean, standard deviation, median, interquartile range: length (cm) 3.16+/-0.68, 3.3, 0.675 vs 3.06+/-0.62, 3.3, 1.1; P=0.645; width (cm) 1.02+/-0.23, 1.0, 0.28 vs 0.89+/-0.27, 0.9, 0.38, P=0.12; volume (cm(3)) 1.52+/-0.67, 1.7, 0.86 vs 1.22+/-0.77, 1.09, 1.19, P=0.20). In our study fentanyl caused no major complications in the biliary system and intestine of ventilated preterm and term neonates. Sonographic investigations of the gallbladder under fentanyl treatment may be dispensable. Further investigations are required to assess adverse gastrointestinal effects.
    European Journal of Clinical Pharmacology 11/2006; 62(10):823-7. · 2.74 Impact Factor
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    ABSTRACT: We analyzed the potential prognostic significance of the immunohistochemical expression of androgen and growth factor receptors determined in prostatectomy specimens of patients with prostate cancer. A cohort of 211 patients with locally confined prostate cancer treated with radical prostatectomy with or without antiandrogen pretreatment between January 1, 1990 and August 31, 1996 was observed prospectively. Prostatectomy samples were processed immunohistochemically to visualize androgen and growth factor receptors, of which immunoreaction intensity was scored relative to that of positive control tissue. Clinical postoperative data were processed using the Kaplan-Meier method, log rank test, and univariate and multivariate explorative Cox modeling to evaluate the contribution to overall and relapse-free survival. There were statistical dependencies between the androgen receptor and epidermal growth factor receptor staining indexes. Following data stratification according to the epidermal growth factor receptor staining index the prognosis associated with a low androgen receptor staining index was worse than that with a higher androgen receptor staining index. Cox regression analysis for relapse-free survival confirmed that the risk factors low androgen receptor and increased epidermal growth factor receptor staining were associated with significantly increased relative risk. Univariate Kaplan-Meier analysis showed that patients with grade 3 carcinoma had a worse prognosis than those with better differentiated carcinoma, whereas antiandrogen pretreatment had no influence on overall survival or relapse-free survival. Using a multivariate proportional hazards regression model for data on a cohort of 211 patients with 68 showing relapse/progress or death from disease a low intensity of androgen receptor staining indicated a poor prognosis.
    The Journal of Urology 09/2006; 176(2):532-7. · 3.70 Impact Factor

Publication Stats

691 Citations
114.11 Total Impact Points


  • 2013
    • University of Bonn - Medical Center
      Bonn, North Rhine-Westphalia, Germany
  • 2012
    • Childrens Hospital of Pittsburgh
      Pittsburgh, Pennsylvania, United States
  • 2001–2011
    • University of Cologne
      • • Department of Internal Medicine
      • • Division of Neonatology and Pediatric Intensive Care
      Köln, North Rhine-Westphalia, Germany
  • 2006
    • Jung-Stilling-Krankenhaus
      Siegen, North Rhine-Westphalia, Germany