scholarly journals Radiation Dose and Fluoroscopy Time of Endovascular Treatment in Patients with Intracranial Lateral Dural Arteriovenous Fistulae

2020 ◽  
Author(s):  
Robert Forbrig ◽  
Robert Stahl ◽  
Lucas L. Geyer ◽  
Yigit Ozpeynirci ◽  
Thomas Liebig ◽  
...  
Keyword(s):  
Low Dose ◽  
Endovascular Embolization ◽  
Fluoroscopy Time ◽  
Low Grade ◽  
Endovascular Technique ◽  
Dose Area Product ◽  
Single Center Study ◽  
Life Threatening ◽  
Area Product ◽  
Dosimetry Data

Abstract Purpose Intracranial lateral dural arteriovenous fistula (LDAVF) represents a specific subtype of cerebrovascular fistulae, harboring a potentially life-threatening risk of brain hemorrhage. Fluoroscopically guided endovascular embolization is the therapeutic gold standard. We provide detailed dosimetry data to suggest novel diagnostic reference levels (DRL). Methods Retrospective single-center study of LDAVFs treated between January 2014 and December 2019. Regarding dosimetry, the dose area product (DAP) and fluoroscopy time were analyzed for the following variables: Cognard scale grade, endovascular technique, angiographic outcome, and digital subtraction angiography (DSA) protocol. Results A total of 70 patients (19 female, median age 65 years) were included. Total median values for DAP and fluoroscopy time were 325 Gy cm2 (25%/75% percentile: 245/414 Gy cm2) and 110 min (68/142min), respectively. Neither median DAP nor fluoroscopy time were significantly different when comparing low-grade with high-grade LDAVF (Cognard I + IIa versus IIb–V; p > 0.05, each). Transvenous coil embolization yielded the lowest dosimetry values, with significantly lower median values when compared to a combined transarterial/transvenous technique (DAP 290 Gy cm2 versus 388 Gy cm2, p = 0.031; fluoroscopy time 85 min versus 170 min, p = 0.016). A significant positive correlation was found between number of arterial feeders treated by liquid embolization and both DAP (rs = 0.367; p = 0.010) and fluoroscopy time (rs = 0.295; p = 0.040). Complete LDAVF occlusion was associated with transvenous coiling (p = 0.001). A low-dose DSA protocol yielded a 20% reduction of DAP (p = 0.021). Conclusion This LDAVF study suggests several local DRLs which varied substantially dependent on the endovascular technique and DSA protocol.

scholarly journals Radiation Dose and Fluoroscopy Time of Diagnostic Angiography in Patients with Spinal Dural Arteriovenous Fistula

2022 ◽  
Author(s):  
Yigit Ozpeynirci ◽  
Christoph Trumm ◽  
Robert Stahl ◽  
David Fischer ◽  
Thomas Liebig ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Low Dose ◽  
Fluoroscopy Time ◽  
Reference Level ◽  
Spinal Angiography ◽  
Spinal Dural Arteriovenous Fistula ◽  
Dose Area Product ◽  
Arteriovenous Fistulas ◽  
Diagnostic Angiography ◽  
Area Product

Abstract Purpose Spinal dural arteriovenous fistulas (SDAVFs) represent the most common indication for a spinal angiography. The diagnostic reference level (DRL) for this specific endovascular procedure is still to be determined. This single-center study provides detailed dosimetrics of diagnostic spinal angiography performed in patients with SDAVFs. Methods Retrospective analysis of all diagnostic spinal angiographies between December 2011 and January 2021. Only patients with an SDAVF who had baseline magnetic resonance angiography (MRA), diagnostic digital subtraction angiography (DSA), treatment and follow-up at this institution were included. Dose area product (DAP, Gy cm2) and fluoroscopy time were compared between preoperative and postoperative angiographies, according to SDAVF locations (common versus uncommon), MRA results at baseline (positive versus negative) and DSA protocols (low-dose, mixed-dose, normal-dose). The 75th percentile of the DAP distribution was used to define the local DRL. Results A total of 62 spinal angiographies were performed in 25 patients with SDAVF. Preoperative angiographies (30/62, 48%) yielded a significantly higher DAP and longer fluoroscopy time when compared to postoperative angiographies (32/62, 53%) (p < 0.01). The local DRL was 329.41 Gy cm2 for a nonspecific (n = 62), 395.59 Gy cm2 for a preoperative and 138.6 Gy cm2 for a postoperative spinal angiography. Preoperative angiography of uncommonly located SDAVFs yielded a significantly longer fluoroscopy time (p = 0.02). The MRA-based fistula detection had no significant impact on dosimetrics (p > 0.05). A low-dose protocol yielded a 61% reduction of DAP. Conclusion The results of the present study suggest novel DRLs for spinal angiography in patients with SDAVF. Dedicated low-dose protocols enable radiation dose optimization in these procedures.

scholarly journals Feasibility of low-dose digital pulsed video-fluoroscopic swallow exams (VFSE): effects on radiation dose and image quality

2017 ◽  
Vol 58 (9) ◽  
pp. 1037-1044 ◽  
Author(s):  
Jakob Weiss ◽  
Mike Notohamiprodjo ◽  
Klement Neumaier ◽  
Minglun Li ◽  
Wilhelm Flatz ◽  
...  
Keyword(s):  
Image Quality ◽  
Radiation Dose ◽  
Dose Reduction ◽  
Low Dose ◽  
Research Evaluation ◽  
Diagnostic Image Quality ◽  
Organ Doses ◽  
Dose Area Product ◽  
Thermoluminescent Dosimeters ◽  
Area Product

Background Fluoroscopy is a frequently used examination in clinical routine without appropriate research evaluation latest hardware and software equipment. Purpose To evaluate the feasibility of low-dose pulsed video-fluoroscopic swallowing exams (pVFSE) to reduce dose exposure in patients with swallowing disorders compared to high-resolution radiograph examinations (hrVFSE) serving as standard of reference. Material and Methods A phantom study (Alderson-Rando Phantom, 60 thermoluminescent dosimeters [TLD]) was performed for dose measurements. Acquisition parameters were as follows: (i) pVFSE: 76.7 kV, 57 mA, 0.9 Cu mm, pulse rate/s 30; (ii) hrVFSE: 68.0 kV, 362 mA, 0.2 Cu mm, pictures 30/s. The dose area product (DAP) indicated by the detector system and the radiation dose derived from the TLD measurements were analyzed. In a patient study, image quality was assessed qualitatively (5-point Likert scale, 5 = hrVFSE; two independent readers) and quantitatively (SNR) in 35 patients who subsequently underwent contrast-enhanced pVFSE and hrVFSE. Results Phantom measurements showed a dose reduction per picture of factor 25 for pVFSE versus hrVFSE images (0.0025 mGy versus 0.062 mGy). The DAP (µGym2) was 28.0 versus 810.5 (pVFSE versus hrVFSE) for an average examination time of 30 s. Direct and scattered organ doses were significantly lower for pVFSE as compared to hrVFSE ( P < 0.05). Image quality was rated 3.9 ± 0.5 for pVFSE versus the hrVFSE standard; depiction of the contrast agent 4.8 ± 0.3; noise 3.6 ± 0.5 ( P < 0.05); SNR calculations revealed a relative decreased of 43.9% for pVFSE as compared to hrVFSE. Conclusion Pulsed VFSE is feasible, providing diagnostic image quality at a significant dose reduction as compared to hrVFSE.

Analysis of Radiation Exposure during Endovascular Aneurysm Repair

2012 ◽  
Vol 78 (10) ◽  
pp. 1029-1032 ◽  
Author(s):  
Michael Butler ◽  
Madhukar S. Patel ◽  
Samuel E. Wilson
Keyword(s):  
Radiation Exposure ◽  
Endovascular Aneurysm Repair ◽  
Abdominal Aortic Aneurysm Repair ◽  
Fluoroscopy Time ◽  
Potential Hazard ◽  
Dose Area Product ◽  
Contrast Volume ◽  
Using Data ◽  
Area Product ◽  
Aneurysm Repair

Endovascular aneurysm repair (EVAR) is now the preferred procedure for abdominal aortic aneurysm repair. As a result of the need for fluoroscopy during EVAR, radiation exposure is a potential hazard. We studied the quantity of radiation delivered during EVAR to identify risks for excessive exposure. Fluoroscopy time, contrast volume used, and procedural details were recorded prospectively during EVARs. Using data collected from similar EVARs, an equation was derived to calculate approximate dose-area product (DAP) from fluoroscopy time. DAP values were then compared between procedures in which a relevant postdeployment procedure (PDP) was necessary intraoperatively with those without. Clinical data on 17 patients were collected. The mean age of patients was 68 (±9) years. Fluoroscopy times and approximate DAP values were found to be significantly higher in the seven patients with a PDP compared with the 10 patients without an intraoperative PDP (31.2 [±9.6] vs 22.7 [±6.0] minutes, P = 0.033 and 537 [±165] vs 390 [±103] Gy-cm2, P = 0.033, respectively). The average amount of contrast volume used was not significantly different between groups. Radiation emitted during EVARs with PDPs was significantly greater relative to those without PDPs. Device design and operators should thus aim to decrease PDPs and to minimize fluoroscopy time.

scholarly journals Mortality after mechanical thrombectomy in anterior circulation stroke may be higher at nighttime and on weekends

2020 ◽  
Author(s):  
C. Zaeske ◽  
L. Goertz ◽  
J. Kottlors ◽  
M. Schlamann ◽  
O. A. Onur ◽  
...  
Keyword(s):  
Hospital Mortality ◽  
Mechanical Thrombectomy ◽  
Fluoroscopy Time ◽  
Anterior Circulation ◽  
Technical Aspects ◽  
Dose Area Product ◽  
Dosimetric Data ◽  
Key Points ◽  
Procedural Time ◽  
Area Product

Abstract Objectives The objective of this study was to compare clinical outcome and procedural differences of mechanical thrombectomy (MT) during on-call with regular operating hours. We particularly focused on dosimetric data which may serve as potential surrogates for patient outcome. Methods A total of 246 consecutive patients who underwent MT in acute anterior circulation stroke between November 2017 and March 2020 were retrospectively included. Patients treated (1) during standard operational hours (n = 102), (2) daytime on-call duty (n = 38) and (3) nighttime on-call duty (n = 106) were compared with respect to their pre-interventional status, procedural specifics, including dosimetrics (dose area product (DAP), fluoroscopy time and procedural time), and outcome. Results The collectives treated outside the regular operational hours showed an increased in-hospital mortality (standard operational hours 7% (7/102), daytime on-call duty 16% (6/38), nighttime on-call duty 20% (21/106), p = 0.02). Neither the dosimetric parameters nor baseline characteristics other procedural specifics and outcome parameters differed significantly between groups (p > 0.05 each). In most cases (> 90%), a successful reperfusion was achieved (TICI ≥ 2b). Conclusions We found an increased in-hospital mortality in patients admitted at night and during weekends which was not explained by technical aspects of MT. Key Points • There is an increased mortality of stroke patients admitted at night and on weekends. • This is not explained by technical aspects of mechanical thrombectomy. • There were no statistical differences in the comparison of parameters linked to the radiation exposure, such as DAP, fluoroscopy time and procedure time.

Using 7.5 frames per second reduces radiation exposure in lower extremity peripheral vascular interventions

Vascular ◽  
2014 ◽  
Vol 23 (3) ◽  
pp. 240-244 ◽  
Author(s):  
Nuri I Akkus ◽  
George S Mina ◽  
Abdulrahman Abdulbaki ◽  
Fereidoon Shafiei ◽  
Neeraj Tandon
Keyword(s):  
Radiation Dose ◽  
Radiation Exposure ◽  
Success Rate ◽  
Frame Rate ◽  
Fluoroscopy Time ◽  
Peripheral Vascular ◽  
Dose Area Product ◽  
Group A ◽  
Group B ◽  
Area Product

Background Peripheral vascular interventions can be associated with significant radiation exposure to the patient and the operator. Objective In this study, we sought to compare the radiation dose between peripheral vascular interventions using fluoroscopy frame rate of 7.5 frames per second (fps) and those performed at the standard 15 fps and procedural outcomes. Methods We retrospectively collected data from consecutive 87 peripheral vascular interventions performed during 2011 and 2012 from two medical centers. The patients were divided into two groups based on fluoroscopy frame rate; 7.5 fps (group A, n = 44) and 15 fps (group B, n = 43). We compared the demographic, clinical, procedural characteristics/outcomes, and radiation dose between the two groups. Radiation dose was measured as dose area product in micro Gray per meter square. Results Median dose area product was significantly lower in group A (3358, interquartile range (IQR) 2052–7394) when compared to group B (8812, IQR 4944–17,370), p < 0.001 with no change in median fluoroscopy time in minutes (18.7, IQR 11.1–31.5 vs. 15.7, IQR 10.1–24.1), p = 0.156 or success rate (93.2% vs. 95.3%), p > 0.999. Conclusion Using fluoroscopy at the rate of 7.5 fps during peripheral vascular interventions is associated with lower radiation dose compared to the standard 15 fps with comparable success rate without associated increase in the fluoroscopy time or the amount of the contrast used. Therefore, using fluoroscopy at the rate of 7.5 fps should be considered in peripheral vascular interventions.

scholarly journals Electrophysiological procedures for the use of the RPC: without hindrance and negligible radiation

2018 ◽  
Vol 1 (1) ◽  
pp. 01-03
Author(s):  
Matvei Ilya ◽  
Vladislav Gleb
Keyword(s):  
Dose Reduction ◽  
Low Dose ◽  
Sensitivity Threshold ◽  
Visualization Technique ◽  
Dose Area Product ◽  
Major Benefit ◽  
Electrophysiological Procedures ◽  
High Doses ◽  
Area Product ◽  
Personal Dosimeter

Background: Fluoroscopy is the main visualization technique for EP procedures. A radiation protection cabin (RPC) shielded with 2 mm lead-equivalent walls was tested as an alternative protection tool (Cathpax®, Lemer Pax). Methods: To assess the scattered radiation to the operator inside the RPC an electronic personal dosimeter (EPD; Mk2, Thermo Electron) was placed at the neck level of the operator. A second EPD was located outside the RPC at 150 cm height from the floor, to record the presumable head radiation dose. Results: Radiation doses were measured in a total of 138 consecutive patients (age 54±16 yrs, BMI 28±5 kg/m2 (18-45), 64% male) undergoing a variety of ablation procedures (SVT=75, AFL=32, AF=17, VT=14). Median fluoroscopy time was 39 min (7-140), the cumulative dose-area product (DAP) 4702 cGy.cm2 (493-65620). Doses outside the RPC showed a median of 135 µSv (1-4881). Doses inside the RPC were detected only at sensitivity threshold or background levels (mean 0.2SD0.7 µSv, median 0.0, range 0-4). The dose reduction to the operator was highest for AF ablations (354 vs 0.5 µSv, respectively; p<0.001). The total accumulated dose outside the RPC was 37883 µSv for all 138 procedures, whereas for the protected operator inside only 30 µSv. Conclusions: There were highly concordant low dose values measured for the operator inside the RPC in comparison to high doses outside the RPC. The use of a RPC represents a major benefit over a lead apron and contributes to a significant dose reduction as low as reasonably achievable (ALARA principle).

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