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Dive into the research topics where Johannes Petersen is active.

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Featured researches published by Johannes Petersen.


BJUI | 2009

Kidney fusion anomalies revisited: clinical and radiological analysis of 209 cases of crossed fused ectopia and horseshoe kidney

Bernhard Glodny; Johannes Petersen; Karin J. Hofmann; Claudia Schenk; R. Herwig; Thomas Trieb; Christian Koppelstaetter; Iris Steingruber; Peter Rehder

To analyse the morphological appearance of horseshoe kidneys (HKs) and crossed fused ectopia (CFE) and to assess the frequency and clinical significance of associated anomalies and diseases.


BMC Urology | 2009

Normal kidney size and its influencing factors - a 64-slice MDCT study of 1.040 asymptomatic patients

Bernhard Glodny; Verena Unterholzner; Bernadette Taferner; Karin J. Hofmann; Peter Rehder; Alexander Strasak; Johannes Petersen

BackgroundNormal ultrasound values for pole-to-pole kidney length (LPP) are well established for children, but very little is known about normal kidney size and its influencing factors in adults. The objectives of this study were thus to establish normal CT values for kidney dimensions from a group of unselected patients, identify potential influencing factors, and to estimate their significance.MethodsIn multiphase thin-slice MDCTs of 2.068 kidneys in 1.040 adults, the kidney length pole to pole (LPP), parenchymal (PW) and cortical width (CW), position and rotation status of the kidneys, number of renal arteries, pyelon width and possible influencing factors that can be visualized, were recorded from a volume data set. For length measurements, axes were adjusted individually in double oblique planes using a 3D-software. Analyses of distribution, T-tests, ANOVA, correlation and multivariate regression analyses were performed.ResultsLPP was 108.5 ± 12.2 mm for the right, and 111.3 ± 12.6 mm for the left kidney (p < 0.0001 each). PW on the right side was 15.4 ± 2.8 mm, slightly less than 15.9 ± 2.7 mm on the left side (p < 0.0001), the CW was the same (6.6 ± 1.9 mm). The most significant independent predictors for LPP, CW, and PW were body size, BMI, age, and gender (p < 0.001 each). In men, the LPP increases up to the fifth decade of life (p < 0.01). It is also influenced by the position of the kidneys, stenoses and number of renal arteries (SRA/NRA), infarctions suffered, parapelvic cysts, and absence of the contralateral kidney; CW is influenced by age, position, parapelvic cysts, NRA and SRA, and the PW is influenced in addition by rotation status (p < 0.05 each). Depending on the most important factors, gender-specific normal values were indicated for these dimensions, the length and width in cross section, width of the renal pelvis, and parenchyma-renal pyelon ratio.ConclusionsDue to the complex influences on kidney size, assessment should be made individually. The most important influencing factors are BMI, height, gender, age, position of the kidneys, stenoses and number of renal arteries.


BMC Pulmonary Medicine | 2012

Systemic air embolism during percutaneous core needle biopsy of the lung: frequency and risk factors

Martin C. Freund; Johannes Petersen; Katharina C Goder; Tillmann Bunse; Franz J. Wiedermann; Bernhard Glodny

BackgroundDetection of risk factors for an air embolism in the left atrium, left ventricle, or systemic circulation (systemic air embolism, SAE) during a percutaneous core needle biopsy (PCNB) of the thorax.MethodsIn a retrospective observational study, all PCNBs of the thorax in 610 patients between 2007 and 2009 were analyzed. The SmartStep™ technique (General Electric) was used for the biopsy, with which the examiner can prepare a batch of three 1.25-mm or 2.5-mm collimated slices within a second using a foot switch in the CT room to check the needle position. The image data thus generated and the control CT scans that followed were examined retrospectively for the presence of intravascular air. Intravascular air was defined as two or more adjacent voxels with absorption values of < -200 HU in the left atrium, left ventricle, aorta, or arteries during or after the procedure. The univariate statistical analysis of categorical variables was made using 2 by 2 tables and the Fisher test. The groups were compared using the Mann-Whitney test. Finally, a multivariate logistic regression analysis was used to identify independent risk factors for the occurrence of an SAE.ResultsThe radiological incidence of an SAE during a PCNB was 3.8% (23/610 patients), whereas the clinically apparent incidence was 0.49%. Two patients developed clinical symptoms consisting of transient hemiplegia or transient amaurosis; one died due to a fatal SAE of the coronary arteries. The mortality was thus 0.16%. The depth of the needle in the lesion (Wald: 6.859), endotracheal anesthesia (Wald: 5.721), location of the lesion above the level of the left atrium (Wald: 5.159), and prone position of the patients (Wald: 4.317) were independent risk factors for the incidence of an SAE (p < 0.05 each). Using explorative criteria, the acute angle of the needle to the tumor surface, and the transition of ventilated lung were independent factors. The frequency of biopsies, needle penetration depth, and tumor location near the diaphragm or in the lower lobe also played a subordinate role, not however, the needle penetration depth through the lung.ConclusionIf possible, the PCNB should be performed under local anesthesia. We recommend avoiding endotracheal anesthesia and prone position. Whenever possible, patients should be positioned on the back in such a way that the tumor is lower than the left atrium. The tip of the needle should be within the tumor during the biopsy procedure.


European Radiology | 2009

A method for calcium quantification by means of CT coronary angiography using 64-multidetector CT: very high correlation with agatston and volume scores

Bernhard Glodny; Bettina Helmel; Thomas Trieb; Claudia Schenk; Bernadette Taferner; Verena Unterholzner; Alexander Strasak; Johannes Petersen

To find out whether calcium scoring of the coronary arteries (CAC scoring) could be carried out with a CT angiography of the coronary arteries (CTCA) in a single CT data acquisition. The Agatston and V130 scores for 113 patients were assessed. A calcium volume score (V600 score) was compiled from the CTCA data sets. Intra- and interobserver correlations were excellent (ρ > 0.97). The intra- and interobserver repeatability coefficients were extremely low, increasing in magnitude from the V600 score to the V130 and Agatston scores. The V600 score underestimates the coronary calcium burden. However, it has a linear relation to the Agatston and V130 scores. Thus, they are predictable from the values of the V600 score. The V600 score shows a linear relation to the classic CAC scores. Due to its extremely high reliability, the score may be a feasible alternative for classic CAC scoring methods in order to reduce radiation dosages.


Surgical Neurology | 2008

Endovascular therapy of distal anterior cerebral artery aneurysms : an effective treatment option

Peter Waldenberger; Johannes Petersen; Andreas Chemelli; Claudia Schenk; Ingrid Gruber; Alexander Strasak; Wilhelm Eisner; Ronny Beer; Bernhard Glodny

BACKGROUND Surgical treatment of APAs is associated with relatively high morbidity and mortality. The aim of this study was to illustrate the technical achievements of endovascular procedures in the distal anterior cerebral artery area, technical difficulties and how they can be overcome, and the outcome of endovascular treatment of APAs. METHODS Between 1997 and 2006, of 49 patients with APAs at our institution, 29 were treated endovascularly (4.1% of all endovascularly treated aneurysms; F:M = 3.8; mean age, 52.8 +/- 11.5 years), and 12 were treated surgically. Twenty-one (72.4%) of the endovascularly treated patients had a subarachnoid hemorrhage. The mean observation period was 25 +/- 22.8 months. RESULTS In 27 (93.1%) cases, complete occlusion of the aneurysm was achieved. The intervention led to 5 (17.2%) cases of minor complications with no neurologic deficits: 2 thromboembolisms, 1 local thrombus, 1 occlusion, and 1 recurrent hemorrhage. Mortality related to the intervention was 3.4%. There was no morbidity associated with the elective procedures. The dome-to-neck ratio is the main predictor of reperfusion. The most important factor impairing the outcome in terms of the GOS status is the presence of an intraparenchymal hematoma, followed by thrombembolic complications. CONCLUSION Endovascular treatment of APAs is feasible, safe, and effective. Mortality and morbidity are comparable with surgical therapy. An intraparenchymal hematoma has a severe negative influence on the patients condition after rehabilitation. In these cases, surgical intervention should be considered. In case of incomplete occlusion of the aneurysm, prompt reintervention is required.


Liver International | 2016

Excellent post-transplant survival in patients with intermediate stage hepatocellular carcinoma responding to neoadjuvant therapy.

Armin Finkenstedt; Anja Vikoler; Manuela Portenkirchner; Kerstin Mülleder; Manuel Maglione; Christian Margreiter; Patrizia Moser; Wolfgang Vogel; Reto Bale; Martin C. Freund; Anna K. Luger; Herbert Tilg; Johannes Petersen; Stefan Schneeberger; Ivo Graziadei; Heinz Zoller; Bernhard Glodny

Current treatment guidelines preclude liver transplantation for patients with BCLC B (intermediate stage) HCC, and expanding transplantation criteria for selected patients beyond early stage HCC remains controversial. The aim of this study was to determine stage‐dependent HCC recurrence and overall survival rates in transplant recipients and the impact of response to neoadjuvant treatment on outcome.


Clinics | 2013

The occurrence of dental caries is associated with atherosclerosis

Bernhard Glodny; Parinaz Nasseri; Adriano Crismani; Elisabeth Schoenherr; Anna K. Luger; Kristina Bertl; Johannes Petersen

OBJECTIVE: Previous studies have suggested that marginal periodontitis is a risk factor for developing atherosclerosis. The objective of this study was to determine whether caries may also be associated with atherosclerosis. METHODS: The computed tomography data sets of 292 consecutive patients, 137 women and 155 men with a mean age of 54.1±17.3 years, were analyzed. Caries were quantified based on the number of decayed surfaces of all the teeth, and periodontitis was quantified on the basis of the horizontal bone loss in the jaw. The presence of chronic apical periodontitis (CAP) was assessed, and the aortic atherosclerotic burden was quantified using a calcium scoring method. RESULTS: The patients with <1 caries surfaces/tooth had a lower atherosclerotic burden (0.13±0.61 mL) than patients with ≥1 caries surfaces/tooth. The atherosclerotic burden was greater in patients with a higher number of lesions with pulpal involvement and more teeth with chronic apical periodontitis. In the logistical regression models, age (Wald 49.3), number of caries per tooth (Wald 26.4), periodontitis (Wald 8.6), and male gender (Wald 11) were found to be independent risk factors for atherosclerosis. In the linear regression analyses, age and the number of decayed surfaces per tooth were identified as influencing factors associated with a higher atherosclerotic burden, and the number of restorations per tooth was associated with a lower atherosclerotic burden. CONCLUSION: Dental caries, pulpal caries, and chronic apical periodontitis are associated positively, while restorations are associated inversely, with aortic atherosclerotic burden. Prospective studies are required to confirm these observations and answer the question of possible causality.


American Journal of Roentgenology | 2017

Measures to Prevent Air Embolism in Transthoracic Biopsy of the Lung

Bernhard Glodny; Elisabeth Schönherr; Martin C. Freund; Melanie Haslauer; Johannes Petersen; Alexander Loizides; Astrid E. Grams; Florian Augustin; Franz J. Wiedermann; Rafael Rehwald

OBJECTIVE Systemic air embolism (AE) is a rare but feared complication of transthoracic biopsy with potentially fatal consequences. The aim of the study was to assess the effect of patient positioning during transthoracic biopsy on preventing systemic AE. MATERIALS AND METHODS We compared a historical control group of 610 patients (group 1) who underwent transthoracic biopsy before the implementation of measures to prevent systemic AE during transthoracic biopsy and a group of 1268 patients (group 2) who underwent biopsy after the measures were implemented. The patients in group 2 were placed in the ipsilateral-dependent position so that the lesion being biopsied was located below the level of the left atrium. RESULTS The rate of systemic AE was reduced from 3.77% to 0.16% (odds ratio [OR], 0.040; 95% CI, 0.010-0.177; p < 0.001). Logistic regression analyses identified needle penetration depth, prone position of the patient during biopsy, location above the level of the left atrium, needle path through ventilated lung, and intubation anesthesia as independent risk factors for systemic AE (p < 0.05). Propensity score-matched analyses identified the number of biopsy samples obtained as an additional risk factor (p = 0.003). The rate of pneumothorax was reduced from 15.41% in group 1 to 5.99% in group 2 (OR, 0.374; 95% CI, 0.307-0.546; p < 0.001). CONCLUSION Performing transthoracic biopsy with the patient in an ipsilateral-dependent position so that the lesion is located below the level of the left atrium is an effective measure for preventing systemic AE. Needle path through ventilated lung and intubation anesthesia should be avoided whenever possible.


European Journal of Radiology | 2012

Prediction of the presence of renal artery stenosis by calcium scoring of the abdominal aorta.

Bernhard Glodny; Parinaz Nasseri; Michaela Plaikner; Verena Unterholzner; Peter Rehder; Christian Koppelstätter; Johannes Petersen

OBJECTIVE To establish a method for estimating the probability of renal artery stenosis (RAS) based on the calcium volume score of the aorta (ACS). MATERIALS AND METHODS In a retrospective observation study, CT angiographies acquired on a 64-slice MDCT scanner were analyzed for 1351 patients (female: 531; male 826; mean age 60.9 ± 17.7 years). A volumetric scoring method was used, detecting plaques with a density of more than 600 HU. RESULTS 13.8% of the patients showed a stenosis >50%, 4.1% a stenosis >70%. The ACS was 0.61 ± 1.01 ml calcium. The sensitivity for detection of RAS >50% and RAS >80% was 0.9572 and 1.0, respectively. The negative predictive value (NPV) of a lack of calcification for excluding RAS >50% and RAS >80% was 0.9752 and 1, respectively. As ACS increased, the specificity for RAS >50% increased to 0.9390. With an ACS of 0.380 ml, accuracy reached a maximum of 0.6585. ROC analyses yielded an area under the curve of 0.88 (p<0.0001). Sensitivity, specificity, NPV and PPV are indicated in relation to the degree of RAS, as well as the diagnostic yield of the method, which is valuable in patients older than 50 years. CONCLUSION Due to its extremely high sensitivity and NPV, the ACS is a very useful screening method for RAS. The validity of the method, as well as its diagnostic value is equivalent to that of coronary artery calcium scoring. Lack of calcifications of the aorta renders atherosclerotic RAS highly improbable.


Cases Journal | 2009

CT appearance of a patent impar umbilical artery in an adult woman and related anomalies: a case report and review of the literature

Bernhard Glodny; Benjamin Henninger; Karin J. Hofmann; Thomas Trieb; Johannes Petersen; Peter Rehder

BackgroundWe report on a case of an impar umbilical artery (IUA) in an 18-year-old woman.Case presentationThe aorta branched off at level L2 into a ventral IUA and a dorsal aorta. The strong IUA produced the inferior mesenteric artery (IMA), the renal artery of a left-sided duplex kidney, and the right-sided ovarian artery before it turned to the right to merge into the right common iliac artery. From the aorta arose the lumbar arteries, the median sacral artery, lateral sacral arteries, and iliolumbar arteries before it turned to the left. Both vessels were connected by an artery 0.8 cm in diameter running infraperitoneal, from the left side of which the uterine artery arose for a left paramedian uterus didelphys.ConclusionThis anatomical situation is presented for the first time using an arterial contrast enhanced CT and is discussed within the context of previously known cases.

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Bernhard Glodny

Innsbruck Medical University

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Peter Rehder

Innsbruck Medical University

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Benjamin Henninger

Innsbruck Medical University

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Werner Jaschke

Innsbruck Medical University

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Thomas Trieb

Innsbruck Medical University

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Karin J. Hofmann

Innsbruck Medical University

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Parinaz Nasseri

Innsbruck Medical University

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Anna K. Luger

Innsbruck Medical University

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Claudia Schenk

Innsbruck Medical University

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Verena Unterholzner

Innsbruck Medical University

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