Richard Nolz

Richard Nolz

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Research Focus & Metrics

Academic Career Length

18Years (2009-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 April 2012 in Journal of Endovascular Therapy
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RNRichard Nolz
Richard Nolz
HTHarald Teufelsbauer
Harald Teufelsbauer
UAUlrika Asenbaum
Ulrika Asenbaum
DBDietrich Beitzke
Dietrich Beitzke
MFMartin Funovics
Martin Funovics
MSMaria Schoder
Maria Schoder
Purpose To evaluate the frequency of type II endoleaks after endovascular aneurysm repair (EVAR) and to compare sac diameter and neck changes in patients with type II endoleak to endoleak-free patients with at least 3-year imaging follow-up. Methods Among 407 consecutive EVAR patients, 109 patients (101 men; mean age 72.1 years, range 55–86) had at least 3-year computed tomography (CT) data and no type I or III endoleak. In this cohort, 49 patients presented with a type II endoleak at some time and 60 patients had no endoleak. Patients with type II endoleaks were further divided into subgroups based on the vessel origin and the perfusion status (persistent or transient). The course of the perfusion status of type II endoleaks and changes in the aneurysm sac diameters, neck diameters, and renal to stent-graft distances (RSD) were evaluated in the defined groups. Reintervention and death rates were also reported. Results The mean follow-up was 68.1±23.8 months. Compared to the no endoleak group, overall sac diameter increased significantly in the type II endoleak group (p=0.007), but vessel origin did not have any influence. With regard to the perfusion status of type II endoleaks, aneurysm sac changes were significantly higher (p = 0.002) in the persistent endoleak group. During the study period, the increase in the proximal neck diameter was significantly higher in the no endoleak group compared to the type II endoleak group (p=0.025). No significant difference was found in RSD changes between the defined groups. Reinterventions were performed in 20 (18.3%) patients (13 for type II endoleak); 2 (1.8%) patients without type II endoleak died of ruptured aneurysm. Conclusion Persistent type II endoleaks led to significant aneurysm sac enlargement, but without increased mortality or rupture rates.

16 May 2018 in European Radiology
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UAUlrika Asenbaum
Ulrika Asenbaum
KKKlaus Kaczirek
Klaus Kaczirek
ABAhmed Ba-Ssalamah
Ahmed Ba-Ssalamah
HRHelmut Ringl
Helmut Ringl
CSChristoph Schwarz
Christoph Schwarz
RNRichard Nolz
Richard Nolz
Objectives To compare the value of functional future liver remnant (functFLR) to established clinical and imaging variables in prediction of post-hepatectomy liver failure (PHLF) after major liver resection. Methods This retrospective, cross-sectional study included 62 patients, who underwent gadoxetic acid enhanced MRI and MDCT within 10 weeks prior to resection of ≥ 4 liver segments. Future liver remnant (FLR) was measured in MDCT using semi-automatic software. Relative liver enhancement for each FLR segment was calculated as the ratio of signal intensity of parenchyma before and 20 min after i.v. administration of gadoxetic acid and given as mean (remnantRLE). Established variables included indocyanine green clearance, FLR, proportion of FLR, weight-adapted FLR and remnantRLE. functFLR was calculated as FLR multiplied by remnantRLE and divided by patient’s weight. The association of measured variables and PHLF was tested with univariate and multivariate logistic regression analysis and receiver operator characteristics (ROC) curves compared with the DeLong method. Results Sixteen patients (25.8%) experienced PHLF. Univariate logistic regression identified FLR (p = 0.015), proportion of FLR (p = 0.004), weight-adapted FLR (p = 0.003), remnantRLE (p = 0.002) and functFLR (p = 0.002) to be significantly related to the probability of PHLF. In multivariate logistic regression analysis, a decreased functFLR was independently associated with the probability of PHLF (0.561; p = 0.002). Comparing ROC curves, functFLR showed a significantly higher area under the curve (0.904; p < 0.001) than established variables. Conclusions functFLR seems to be superior to established variables in prediction of PHLF after major liver resection. Key Points • functFLR is a parameter combining volumetric and functional imaging information, derived from MDCT and gadoxetic acid enhanced MRI. • In comparison to other established methods, functFLR is superior in prediction of post-hepatectomy liver failure. • functFLR could help to improve patient selection prior major hepatic surgery.

19 July 2016 in European Radiology
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Journal Article
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DJD. Javor
D. Javor
AWA. Wressnegger
A. Wressnegger
SUS. Unterhumer
S. Unterhumer
KKKathrin Kollndorfer
Kathrin Kollndorfer
RNRichard Nolz
Richard Nolz
CLChristian Loewe
Christian Loewe
Objectives To assess a single-phase, dual-energy computed tomography (DECT) with a split-bolus technique and reconstruction of virtual non-enhanced images for the detection of endoleaks after endovascular aneurysm repair (EVAR). Methods Fifty patients referred for routine follow-up post-EVAR CT and a history of at least one post-EVAR follow-up CT examination using our standard biphasic (arterial and venous phase) routine protocol (which was used as the reference standard) were included in this prospective trial. An in-patient comparison and an analysis of the split-bolus protocol and the previously used double-phase protocol were performed with regard to differences in diagnostic accuracy, radiation dose, and image quality. Results The analysis showed a significant reduction of radiation dose of up to 42 %, using the single-acquisition split-bolus protocol, while maintaining a comparable diagnostic accuracy (primary endoleak detection rate of 96 %). Image quality between the two protocols was comparable and only slightly inferior for the split-bolus scan (2.5 vs. 2.4). Conclusions Using the single-acquisition, split-bolus approach allows for a significant dose reduction while maintaining high image quality, resulting in effective endoleak identification. Key Points • A single-acquisition, split-bolus approach allows for a significant dose reduction. • Endoleak development is the most common complication after endovascular aortic repair (EVAR). • CT angiography is the imaging modality of choice for aortic aneurysm evaluation.

19 January 2021 in Neurology
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PSPeter Sporns
Peter Sporns
Marios-Nikos PsychogiosMarios-Nikos Psychogios
Marios-Nikos Psychogios
RSRonald Straeter
Ronald Straeter
UHUta Hanning
Uta Hanning
JMJens Minnerup
Jens Minnerup
AKAndre Kemmling
Andre Kemmling
Objective To determine whether thrombectomy is safe in children up to 24 hours after onset of symptoms when selected by mismatch between clinical deficit and infarct. Methods A secondary analysis of the Save ChildS Study (January 2000–December 2018) was performed, including all pediatric patients (<18 years) diagnosed with arterial ischemic stroke who underwent endovascular recanalization at 27 European and United States stroke centers. Patients were included if they had a relevant mismatch between clinical deficit and infarct. Results Twenty children with a median age of 10.5 (interquartile range [IQR] 7–14.6) years were included. Of those, 7 were male (35%), and median time from onset to thrombectomy was 9.8 (IQR 7.8–16.2) hours. Neurologic outcome improved from a median Pediatric NIH Stroke Scale score of 12.0 (IQR 8.8–20.3) at admission to 2.0 (IQR 1.2–6.8) at day 7. Median modified Rankin Scale (mRS) score was 1.0 (IQR 0–1.6) at 3 months and 0.0 (IQR 0–1.0) at 24 months. One patient developed transient peri-interventional vasospasm; no other complications were observed. A comparison of the mRS score to the mRS score in the DAWN and DEFUSE 3 trials revealed a higher proportion of good outcomes in the pediatric compared to the adult study population. Conclusions Thrombectomy in pediatric ischemic stroke in an extended time window of up to 24 hours after onset of symptoms seems safe and neurologic outcomes are generally good if patients are selected by a mismatch between clinical deficit and infarct. Classification of Evidence This study provides Class IV evidence that for children with acute ischemic stroke with a mismatch between clinical deficit and infarct size, thrombectomy is safe.

1 April 2020 in Stroke
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PSPeter Sporns
Peter Sporns
RSRonald Straeter
Ronald Straeter
JMJens Minnerup
Jens Minnerup
HWHeinz Wiendl
Heinz Wiendl
UHUta Hanning
Uta Hanning
OIon behalf of Save ChildS Investigators
on behalf of Save ChildS Investigators
Background and Purpose—: The recent Save ChildS study provides multicenter evidence for the use of mechanical thrombectomy in children with large vessel occlusion arterial ischemic stroke. However, device selection for thrombectomy may influence rates of recanalization, complications, and neurological outcomes, especially in pediatric patients of different ages. We, therefore, performed additional analyses of the Save ChildS data to investigate a possible association of different thrombectomy techniques and devices with angiographic and clinical outcome parameters. Methods—: The Save ChildS cohort study (January 2000–December 2018) analyzed data from 27 European and United States stroke centers and included all pediatric patients (<18 years), diagnosed with arterial ischemic stroke who underwent endovascular recanalization. Patients were grouped into first-line contact aspiration (A Direct Aspiration First Pass Technique [ADAPT]) and non-ADAPT groups as well as different stent retriever size groups. Associations with baseline characteristics, recanalization rates (modified Treatment in Cerebral Infarction), complication rates, and neurological outcome parameters (Pediatric National Institutes of Health Stroke Scale after 24 hours and 7 days; modified Rankin Scale and Pediatric Stroke Outcome Measure at discharge, after 6 and 24 months) were investigated. Results—: Seventy-three patients with a median age of 11.3 years were included. Currently available stent retrievers were used in 59 patients (80.8%), of which 4×20 mm (width×length) was the most frequently chosen size (36 patients =61%). A first-line ADAPT approach was used in 7 patients (9.6%), and 7 patients (9.6%) were treated with first-generation thrombectomy devices. In this study, a first-line ADAPT approach was neither associated with the rate of successful recanalization (ADAPT 85.7% versus 87.5% No ADAPT) nor with the complication rate or the neurological outcome. Moreover, there were no associations of stent retriever sizes with rates of recanalization, complication rates, or outcome parameters. Conclusions—: Our study suggests that neurological outcomes are generally good regardless of any specific device selection and suggests that it is important to offer thrombectomy in eligible children regardless of technique or device selection. Registration—: URL: https://www.drks.de/ ; Unique identifier: DRKS00016528.

28 June 2011 in European Radiology
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DBDietrich Beitzke
Dietrich Beitzke
FWFlorian Wolf
Florian Wolf
GEGundula Edelhauser
Gundula Edelhauser
CPChristina Plank
Christina Plank
RSRüdiger Schernthaner
Rüdiger Schernthaner
CLChristian Loewe
Christian Loewe