dose area product
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Author(s):  
T. C. Meine ◽  
L. S. Becker ◽  
C. L. A. Dewald ◽  
S. K. Maschke ◽  
B. Maasoumy ◽  
...  

Abstract Purpose To assess the feasibility, safety and effectiveness of portal vein recanalization (PVR)–transjugular portosystemic shunt (TIPS) placement via splenic access using a balloon puncture technique. Materials and Methods In a single-center retrospective study from March 2017 to February 2021, 14 consecutive patients with portal hypertension, chronic liver disease and portal vein occlusion or near-complete (> 95%) occlusion were referred for PVR–TIPS placement. Feasibility, safety and effectiveness including procedural characteristics such as technical success, complication profile and splenic access time (SAT), balloon positioning time (BPT), conventional portal vein entry time (CPVET), overall procedure time (OPT), fluoroscopy time (FT), dose–area product (DAP) and air kerma (AK) were evaluated. Results Transsplenic PVR–TIPS using balloon puncture technique was technically feasible in 12 of 14 patients (8 men, 49 ± 13 years). In two patients without detectable intrahepatic portal vein branches, TIPS placement was not feasible and both patients were referred for further treatment with nonselective beta blockers and endoscopic variceal ligation. No complications grade > 3 of the Cardiovascular and Interventional Radiological Society of Europe classification system occurred. The SAT was 25 ± 21 min, CPVET was 33 ± 26 min, the OPT was 158 ± 54 min, the FT was 42 ± 22 min, the DAP was 167.84 ± 129.23 Gy*cm2 and the AK was 1150.70 ± 910.73 mGy. Conclusions Transsplenic PVR–TIPS using a balloon puncture technique is feasible and appears to be safe in our series of patients with obliteration of the portal vein. It expands the interventional options in patients with chronic PVT.


Author(s):  
Yigit Ozpeynirci ◽  
Christoph Trumm ◽  
Robert Stahl ◽  
David Fischer ◽  
Thomas Liebig ◽  
...  

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.


2022 ◽  
Author(s):  
M.K. Saeed ◽  
A.A.M. Asiri ◽  
Q.S. Alhamami ◽  
K. Alshamrani

The purpose of this study was to determine local diagnostic reference levels (DRLs) for patients undergoing intraoral and panoramic dental examinations at the intraoral radiology units of the public hospitals in Najran, Saudi Arabia. DRLs were determined based on measurements of dose area product (DAP) at intraoral and dental panoramic radiology units. This study has covered over 47% of the public hospitals in Najran with the intention to establish the local DRLs for all the possible intraoral and panoramic X-ray examinations for children and adults. For intraoral, the values for the estimated DAP ranged from 6 to 70 mGy.cm2 (average: 27.6, 29.8, 39.9 and 39.6 mGy.cm2 for incisive, both premolar and canine, molar upper and lower jaw, respectively). For panoramic, the mean value of DAP is 61.5 and 89.8 mGy.cm2 for paediatric and adult patients, respectively. DRLs were established at the 3rd quartile for incisive, both premolar and canine, molar upper and lower jaw protocols are 29.2, 37.1, 50.2 and 50.1 mGy.cm2, respectively. Furthermore, DRLs for panoramic radiography for paediatric and adult patients are 72.7 and 92.3 mGy.cm2, respectively. The proposed DRLs were comparable to those previously reported in other countries, such as UK and India.


Vascular ◽  
2021 ◽  
pp. 170853812110633
Author(s):  
Selami Gurkan ◽  
Ozcan Gur ◽  
Ayhan Sahin ◽  
Mehmet Donbaloglu

Background Obesity is a common and growing health problem in vascular surgery patients, as it is in all patient groups. Evidence regarding body mass index (BMI) on endovascular aneurysm repair (EVAR) outcomes is not clear in the literature. We aimed to determine the impact of obesity on perioperative and midterm outcomes of elective EVAR between obese and non-obese patients. Methods Under a retrospective study design, a total of 120 patients (109 males, 11 females, mean age: 74.45 ± 8.59 (53–92 years)) undergoing elective EVAR between June 2012 and May 2020 were reviewed. Patients were stratified into two groups: obese (defined as a body mass index (BMI) ≥ 30 kg/m2) and non-obese (mean BMI < 30 kg/m2 (32.25 ± 1.07 kg/m2 vs 25.85 ± 2.69 kg/m2)). Results Of the 120 patients included in the study, 81 (67.5%) were defined as “nonobese,” while 39 (32.5%) were obese. The mean BMI of the study group was 27.93 ± 3.78 kg/m2. In obese patients, the procedure time, fluoroscopy time, and dose area product (DAP) values were longer than those of non-obese patients: 89.74 ± 20.54 vs 79.69 ± 28.77 min ( p = 0.035), 33.23 ± 10.14 vs 38.17 ± 8.61 min ( p = 0.01) and 133.69 ± 58.17 vs 232.56 ± 51.87 Gy.cm2 ( p < 0.001). Although there was no difference in sac shrinkage at 12-month follow-up, there was a significant decrease at 6-month follow-up in both groups ( p = 0.017). Endoleak occurred in 17.9% ( n = 7) of the obese group versus 11.1% ( n = 9) of the non-obese group ( p = 0.302). Iliac branch occlusion developed in four patients, 3 (3.7%) in the non-obese group and 1 (2.6%) in the obese group ( p = 0.608). The all-cause mortality rate was slightly higher in the obese group; however, it did not differ between the groups ( p = 0.463). Conclusion In addition to the longer procedure times, fluoroscopy times, and DAP values in obese patients, regardless of obesity, significant sac shrinkage in the first 6 months of follow-up was observed in both groups. No difference was documented with regards to mortality or morbidity following EVAR.


Author(s):  
Nicholas K. Brown ◽  
Nazia Husain ◽  
Jennifer Arzu ◽  
Sandhya R. Ramlogan ◽  
Alan W. Nugent ◽  
...  

AbstractPercutaneous balloon pulmonary valvuloplasty (PBPV) is the treatment of choice for isolated pulmonary valve stenosis. While this procedure is highly efficacious and has an excellent safety profile, as currently practiced, patients are obligatorily exposed to the secondary risks of ionizing radiation and contrast media. To mitigate these risks, we developed a protocol which utilized echo guidance for portions of the procedure which typically require fluoroscopy and/or angiography. Ten cases of echo-guided pulmonary valvuloplasty (EG-PBPV) for isolated pulmonary stenosis in children less than a year of age were compared to a historical cohort of nineteen standard cases using fluoroscopy/angiography alone, which demonstrated equivalent procedural outcomes and safety, while achieving a median reduction in radiation (total dose area product) and contrast load of 80% and 84%, respectively. Our early experience demonstrates that EG-PBPV in neonates and infants has results equivalent to standard valvuloplasty but with less radiation and contrast.


Author(s):  
M. Ali ◽  
B. Banavalikar ◽  
M. K. Ghadei ◽  
A. Kottayan ◽  
D. Padmanabhan ◽  
...  

Background. Radiofrequency catheter ablation (CA) has been the treatment of choice in patients with accessory pathway (AP)-mediated tachycardias. Most of these procedures are done under fluoroscopic guidance, leading to significant radiation exposure to the patient and the laboratory personnel. In this analysis, we have looked at the amount of radiation exposure in AP CA procedures performed without the support of a three-dimensional electroanatomic mapping system. We have analyzed changes in exposure indices over the study period and the impact of change in fluoroscopy frame rate (FFR). Objectives. The objectives of this study are to quantify radiation exposure in accessory pathway ablation procedures; to analyze the radiation exposure trend over time; and to evaluate the effect of fluoroscopy frame rate reduction on the radiation exposure indices in these procedures. Methods. All the AP ablation procedures performed at our institute from January 2016 to December 2019 were retrospectively analyzed. The collected data were age, sex, location of APs based on successful site of ablation on fluoroscopy, procedure time, fluoroscopy time, and dose-area product (DAP). Effective dose (ED) was estimated from DAP. The data of procedures performed before January 2018 (“pre” group) were compared with those of the procedures performed after that date (“post” group). Pre-group procedures were performed at an FFR of 7.5 frames per second (fps), and post-group procedures – at an FFR of 3.75 fps. Results. The total number of procedures included in the analysis was 635. The mean age of the patients was 39±14 years, and 401 of them (63%) were males. The most common location of the APs was left lateral (38%). Procedure time and radiation indices showed a significant decrease over the study period (p < 0.001). Post group procedures had significantly shorter procedure time and lower radiation exposure than pre group procedures. Conclusions. A decrease in the FFR was associated with a significant reduction in radiation exposure in AP ablation procedures


2021 ◽  
Vol 8 ◽  
Author(s):  
Florian Straube ◽  
Janis Pongratz ◽  
Alexander Kosmalla ◽  
Benedikt Brueck ◽  
Lukas Riess ◽  
...  

Background: Cryoballoon ablation is established for pulmonary vein isolation (PVI) in paroxysmal atrial fibrillation (AF). The objective was to evaluate CBA strategy in consecutive patients with persistent AF in the initial AF ablation procedure.Material and Methods: Prospectively, patients with symptomatic persistent AF scheduled for AF ablation all underwent cryoballoon PVI. Technical enhancements, laboratory management, safety, single-procedure outcome, predictors of recurrence, and durability of PVI were evaluated.Results: From 2007 to 2020, a total of 1,140 patients with persistent AF, median age 68 years, underwent cryoballoon ablation (CBA). Median left atrial (LA) diameter was 45 mm (interquantile range, IQR, 8), and Congestive heart failure, Hypertension, Age ≥75 years (doubled), Diabetes mellitus, prior Stroke or TIA or thromboembolism (doubled), Vascular disease, Age 65 to 74 years, Sex category (CHA2DS2-VASc) score was 3. Acute isolation was achieved in 99.6% of the pulmonary veins by CBA. Median LA time and median dose area product decreased significantly over time (p &lt; 0.001). Major complications occurred in 17 (1.5%) patients including 2 (0.2%) stroke/transitory ischemic attack (TIA), 1 (0.1%) tamponade, relevant groin complications, 1 (0.1%) significant ASD, and 4 (0.4%) persistent phrenic nerve palsy (PNP). Transient PNP occurred in 66 (5.5%) patients. No atrio-esophageal fistula was documented. Five deaths (0.4%), unrelated to the procedure, occurred very late during follow-up. After initial CBA, arrhythmia recurrences occurred in 46.6% of the patients. Freedom from atrial arrhythmias at 1-, and 2-year was 81.8 and 61.7%, respectively. Independent predictors of recurrence were LA diameter, female sex, and use of the first cryoballoon generation. Repeat ablations due to recurrences were performed in 268 (23.5%) of the 1,140 patients. No pulmonary vein (PV) reconduction was found in 49.6% of the patients and 73.5% of PVs. This rate increased to 66.4% of the patients and 88% of PVs if an advanced cryoballoon was used in the first AF ablation procedure.Conclusion: Cryoballoon ablation for symptomatic persistent AF is a reasonable strategy in the initial AF ablation procedure.


Author(s):  
Yon-Kwon Ihn ◽  
Bum-soo Kim ◽  
Hae Woong Jeong ◽  
Sang Hyun Suh ◽  
Yoo Dong Won ◽  
...  

Purpose: To assess patient radiation doses during diagnostic and therapeutic neurointerventional procedures from multiple centers and propose dose reference level (RL).Materials and Methods: Consecutive neurointerventional procedures, performed in 22 hospitals from December 2020 to June 2021, were retrospectively studied. We collected data from a sample of 429 diagnostic and 731 therapeutic procedures. Parameters including dose-area product (DAP), cumulative air kerma (CAK), fluoroscopic time (FT), and total number of image frames (NI) were obtained. RL were calculated as the 3rd quartiles of the distribution.Results: Analysis of 1160 procedures from 22 hospitals confirmed the large variability in patient dose for similar procedures. RLs in terms of DAP, CAK, FT, and NI were 101.6 Gy·cm<sup>2</sup>, 711.3 mGy, 13.3 minutes, and 637 frames for cerebral angiography, 199.9 Gy·cm<sup>2</sup>, 3,458.7 mGy, 57.3 minutes, and 1,000 frames for aneurysm coiling, 225.1 Gy·cm<sup>2</sup>, 1,590 mGy, 44.7 minutes, and 800 frames for stroke thrombolysis, 412.3 Gy·cm<sup>2</sup>, 4,447.8 mGy, 99.3 minutes, and 1,621.3 frames for arteriovenous malformation (AVM) embolization, respectively. For all procedures, the results were comparable to most of those already published. Statistical analysis showed male and presence of procedural complications were significant factors in aneurysmal coiling. Male, number of passages, and procedural combined technique were significant factors in stroke thrombolysis. In AVM embolization, a significantly higher radiation dose was found in the definitive endovascular cure group.Conclusion: Various RLs introduced in this study promote the optimization of patient doses in diagnostic and therapeutic interventional neuroradiology procedures. Proposed 3rd quartile DAP (Gy·cm<sup>2</sup>) values were 101.6 for diagnostic cerebral angiography, 199.9 for aneurysm coiling, 225.1 for stroke thrombolysis, and 412.3 for AVM embolization. Continual evolution of practices and technologies requires regular updates of RLs.


QJM ◽  
2021 ◽  
Vol 114 (Supplement_1) ◽  
Author(s):  
Ahmed Abdelrazik ◽  
Youssef Amin ◽  
Alaa Roushdy ◽  
Maiy El Sayed

Abstract Aim and objectives The aim of the study is to assess the average radiation doses recorded per procedure in Ain Shams University Hospital pediatric cath lab to set benchmarks of radiation exposure in our institute. Patients and Methods The study included 198 patients who presented to Ain Shams cardiac pediatric cath lab who undergone interventional (BPV, BAV, ASD device closure, VSD device closure, PDA coil/device closure, Coarctation Stent/balloon) and diagnostic (Hemodynamics study, Diagnostic cath) heart catheterization. Radiation doses were measured without any interference with the operator’s preferences. Results Radiation dosages were measured in total AirKerma, Dose area product (DAP), and fluoroscopy time to set the benchmarks for radiation exposure in our institute per procedure. VSD device closure showed the highest radiation exposure followed by Coarctation stenting. Lowest radiation dosage was in PDA coil closure followed by ASD device closure then BPV. Conclusion Benchmarks for radiation exposure per procedure in pediatric cath lab in our institute were set and compared to each other.


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