Klaus Herz

Mr. Klaus Herz

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Research Focus & Metrics

Academic Career Length

15Years (2012-Present)

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

Representative Publications

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Journal Article
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CRChrister Ruff
Christer Ruff
SPSasan Partovi
Sasan Partovi
ISIsabella Strobel
Isabella Strobel
SKStella Kaleth
Stella Kaleth
KHKlaus Herz
Klaus Herz
GGGerd Grözinger
Gerd Grözinger
Background/Objectives: To evaluate radiation exposure in standard interventional radiology procedures using a twin robotic X-ray system compared to a state-of-the-art conventional angiography system. Methods: Standard interventional radiology procedures (port implantation, SIRT, and pelvic angiography) were simulated using an anthropomorphic Alderson RANDO phantom (Alderson Research Laboratories Inc. Stamford, CT, USA) on an above-the-table twin robotic X-ray scanner (Multitom Rax, Siemens Healthineers, Forchheim, Germany) and a conventional below-the-table angiography system (Artis Zeego, Siemens Healthineers, Forchheim, Germany). The phantom’s radiation exposure (representing the potential patient on the procedure table) was measured with thermoluminescent dosimeters. Height-dependent dose curves were generated for examiners and radiation technologists in representative positions using a RaySafe X2 system (RaySafe, Billdal, Sweden). Results: For all scenarios, the device-specific dose distribution differs depending on the imaging chain, with specific advantages and disadvantages. Radiation exposure for the patient is significantly increased when using the Multitom Rax for pelvic angiography compared to the Artis Zeego, which is evident in the dose progression through the phantom’s body as well as in the organ-related radiation exposure. In line with these findings, there is an increased radiation exposure for the performing proceduralist, especially at eye level, which can be significantly minimized by using protective equipment (p < 0.001). Conclusions: In this study, the state-of-the-art conventional below-the-table angiography system is associated with lower radiation dose exposures for both the patient and the interventional radiology physician compared to an above-the-table twin robotic X-ray system for pelvic angiographies. However, in other clinical scenarios (port implantation or SIRT), both devices are suitable options with acceptable radiation exposure.

29 November 2012 in RöFo - Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren
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BWB. Wiesinger
B. Wiesinger
SKS. Kirchner
S. Kirchner
GBG. Blumenstock
G. Blumenstock
KHKlaus Herz
Klaus Herz
JSJ. Schmehl
J. Schmehl
JWJ. Wiskirchen
J. Wiskirchen
Purpose: Comparison of dose area products (DAP) in diagnostic angiography procedures between an image intensifier (II) and a flat panel detector (FPD) angiography system and the evaluation of DAP/body mass index (BMI) dependency. Materials and Methods: An image intensifier system or a flat panel detector system was used to perform 571 diagnostic angiographies (n = 328 and n = 243, respectively) of 5 different types: peripheral arterial, venous, single leg, abdominal and upper extremity. The results were retrospectively analyzed. The DAP, fluoroscopy time (t) and the number of series of the respective interventions as calculated by the respective machines was compared for all interventions and for the respective subtypes and machines. The BMI dependency was calculated separately for both machines for all interventions by subdividing the patients into 6 BMI classes defined by the WHO. Results: The average DAP for all diagnostic interventions was 1958.9 cGy×cm2 (t = 384.6 s, n = 7.85 series) for the II and 2927.4 cGy×cm2 (t = 267.4 s, n = 7.02 series) for the FPD. Group-dependent differences ranged between + 21 and + 252 % when using the FPD system. After time standardization, the respective increases were found to be 120 % for the FPD system. The DAPs increased considerably in patients with higher BMIs (766.7 cGy × cm2 – 6892.6 cGy × cm2, II machine, 950.5 cGy × cm2 – 12 487.7 cGy × cm2, FPD machine) with a greater DAP gain seen for the FPD. The average duration of the interventions was higher using the II machine. Conclusion: The use of an FPD system led to higher DAP values compared to the II system in diagnostic angiographic procedures. In addition, increased BMI values led to higher DAPs, especially for the FPD machine. However, the average fluoroscopy times were shorter. Ziel: Dosisflächenproduktvergleich (Dose-Area-Products, DAP) bei diagnostischen Angiografien zwischen einem Bildverstärkerangiografiesystem (II) und einem Flachbilddetektorsystem (FPD) und Erhebung der DAP/Body-Mass-Index (BMI) Abhängigkeit. Material und Methoden: Die folgenden 571 diagnostischen Angiografien wurden mit einem Bildverstärker- (n = 328) und mit einem Flachbilddetektorangiografiesystem (n = 243) retrospektiv evaluiert: arterielle Beckenbeinangiografien, venöse Beckenbeinangiografien, Feinnadelangiografien, abdominelle und obere Extremitätenangiografien. Erhoben wurde retrospektiv das Dosisflächenprodukt (DAP), die Fluoroskopiezeit (t) sowie die Serienanzahl der entsprechenden Interventionen an den entsprechenden Geräten. Die BMI-Abhängigkeit des DAPs wurde separat für beide Geräte und alle Interventionsklassen nach den 6 WHO-BMI-Klassen vorgenommen. Ergebnisse: Das durchschnittliche DAP über alle Interventionen lag bei 1958,9 cGy×cm2 (t = 384,6 s, n = 7,85 Serien) für das II und bei 2927,4 cGy×cm2 (t = 267,4 s, n = 7,02 Serien) für das FPD-Gerät. Der DAP-Zuwachs nach Interventionsgruppe betrug zwischen + 21 % und + 252 % für das FPD-System. Nach Zeitnormierung betrug der DAP-Zuwachs beim FPD-Gerät 120 %. Die DAPs nahmen beim FPD-Gerät mit steigendem BMI deutlicher zu im Vergleich zum II-Gerät (766,7 cGy×cm2 – 6892,6 cGy×cm2 II-System, 950,5 cGy/cm2 – 12 487,7 cGy/cm2, FPD-System). Die durchschnittliche Durchleuchtungszeit war beim II-System höher. Schlussfolgerung: Beim Gebrauch des FPD-Systems entstanden deutlich höhere DAP-Werte im Vergleich zum II-System bei diagnostischen Angiografien. Bei höherem BMI war der DAP-Zuwachs am FPD-Gerät höher, die Fluoroskopiezeiten jedoch deutlich geringer.

1 April 2021 in Radiation Measurements
Verified
Journal Article
Closed access
ISI. Strobel
I. Strobel
VBV. Bandalo
V. Bandalo
KHKlaus Herz
Klaus Herz
GFG. Fehrenbacher
G. Fehrenbacher
GGG. Grözinger
G. Grözinger
HHH. Hoedlmoser
H. Hoedlmoser