Dose Area Product Research Articles

Augmented fluoroscopy-guided dye localization for small pulmonary nodules in hybrid operating room: intrathoracic stamping versus transbronchial marking.

We developed a novel augmented fluoroscopy-guided intrathoracic stamping technique for localizing small pulmonary nodules in the hybrid operating room. We conducted an observational study to investigate the feasibility of this technique and retrospectively compared two augmented fluoroscopy-guided approaches: intrathoracic and transbronchial. From August 2020 to March 2023, consecutive patients underwent single-stage augmented fluoroscopy-guided localization under general anaesthesia. This included intrathoracic stamping and bronchoscopic lung marking, followed by thoracoscopic resection in a hybrid operating room. Comparative analyses were performed between the two groups. The data of 50 patients in the intrathoracic stamping and 67 patients in the bronchoscopic lung marking groups were analysed. No significant difference was noted in demographic data between the groups, except a larger lesion depth in the bronchoscopic lung marking group (14.7 ± 11.7 vs 11.0 ± 5.8mm, p = 0.029). Dye localization was successfully performed in 49 intrathoracic stamping group patients (98.0%) and 67 bronchoscopic lung marking group patients (100%). No major procedure-related complications occurred in either group; however, the time flow (total anaesthesia time/global operating room time) was longer, and the radiation exposure (fluoroscopy duration/total dose area product) was larger in the bronchoscopic lung marking group. Augmented fluoroscopic stamping localization under intubated general anaesthesia is feasible and safe, providing an alternative with less global operating room time and lower radiation exposure for image-guided thoracoscopic surgery in the hybrid operating room.

QUANTIFYING RADIATION EXPOSURE IN THE RADIOLOGICAL INVESTIGATION OF NON-ARTHRITIC HIP PAIN

Radiological investigations are essential in the work-up of patients presenting with non-arthritic hip pain, to allow close review of the complex anatomy around the hip and proximal femur. The aim of this study is to quantify the radiation exposure associated with common radiological investigations performed in assessing young adult patients presenting with non-arthritic hip pain.A retrospective review of our UK tertiary hip preservation centre institutional imaging database was performed. Data was obtained for antero-posterior, cross-table lateral and frog-lateral radiographs, along with data for the low dose CT hip protocol and the Mako CT Hip protocol. The radiation dose of each imaging technique was measured in terms of dose-area product (DAP) with units of mGycm2, and the effective doses (ED, mSv) calculated.The mean effective radiation dose for hip radiographs was in the range 0.03 to 0.83mSv (mean DLP 126.7–156.2 mGycm2). The mean effective dose associated with the low-dose CT hip protocol was 3.04mSv (416.8 mGycm2) and for the Stryker Mako CT Hip protocol was 8.4mSv (1061 mGycm2). The radiation dose associated with use of CT imaging was significantly greater than plain radiographs (p<0.005)Investigation of non-arthritic hip pain can lead to significant ionising radiation exposure for patients. In our institution, the routine protocol is to obtain an anteroposterior radiograph and then a specific hip sequence 3 Tesla MRI including anteversion views. This provides the necessary information in the majority of cases, with CT scanning reserved for more complex cases where we feel there is a specific indication. We would encourage the hip preservation community to carefully consider and review the use of ionising radiation investigations.

Embolization of Middle Meningeal Arteries for Symptomatic Subacute Subdural Hematoma in Patients with Cancer

PurposeThe purpose of this study was to evaluate the technical and clinical success of middle meningeal artery (MMA) embolization performed for symptomatic subacute subdural hematoma (SDH) in patients with cancer. MethodsThis study retrospectively included 23 consecutive patients (12 men, 11 women; median age 61 years, interquartile range: 55.5–75.5) who underwent 34 MMA angiograms for symptomatic SDH in 2022 and 2023. Median SDH thickness was 10.5mm (7-12). Median platelet count was 117 K/mcL (54.5–218). Ten patients (43.5%, 10/23) had hematologic malignancies, 7 patients (30.4%, 7/23) had surgery. Fluoroscopy time (FT), reference dose (RD), and kerma area product (Kap) were analyzed. Adverse events and outcomes were recorded. ResultsThe median imaging and clinical follow-up were 65 days (36.5–190.5) and 163 days (86–274), respectively. The technical success rate was 91.2% (31/34) as 3 MMA were not identified in 2 patients. Median procedure duration was 61 min (55.5–75.5). Median FT was 21.6 min (15.5–31.8); median RD was 158 mGy (96–256); and median Kap was 32.9 Gy.cm2 (20.4–45.1). No further intervention was needed. For 16 patients, SDH resolved after in median 59.5 days (50-90). For 7 patients, SDH remained visible on the last imaging follow-up performed at 24 days in median (6.5-36.5). No predictive factor of failure was identified. The adverse event rate was 1/23 (4.3%). Eight patients (34.8%, 8/23) died during follow-up from progression of cancer. ConclusionsMMA embolization of symptomatic SDH in patients with cancer appears safe and is associated with improvement in clinical symptoms.

Assessing the Efficacy of RADPAD Protection Drape in Reducing Radiation Exposure to Operators in the Cardiac Catheterization Laboratory: A Systematic Review and Meta-Analysis.

One of the leading environmental hazards, ionizing radiation, is linked to several detrimental health consequences in the body. RADPAD(Worldwide Innovations & Technologies, Inc., Kansas City, Kansas) is a sterile, lead-free, lightweight, disposable radiation protection shield. We conducted a systematic review and meta-analysis to determine the effectiveness of RADPAD protection drapes in the cardiac catheterization lab and how they can aid interventional cardiologists in becoming subjected to less scatter radiation. PubMed, Embase, and Google Scholar were searched for studies discussing the efficacy of RADPAD protection drapes in reducing radiation exposure to operators in the cardiac catheterization laboratory. A random-effects model was used to pool odds ratios (ORs) and 95% confidence intervals (CIs) for endpoints: primary operator exposure dose, dose area product (DAP), relative exposure, and screening time. Our analysis included 892 patients from six studies. Compared to the No-RADPAD group, primary operator exposure dose (E) was significantly lower in the RADPAD group (OR: -0.9, 95% CI: -1.36 to -0.43, I2= 80.5%, p = 0.0001). DAP was comparable between both groups (OR: 0.008, 95% CI: -0.12 to -0.14, I2= 0%, p = 0.9066). There was no difference in the relative exposure (E/DAP) (OR: -0.47, 95% CI: -0.96 to 0.02, I2= 0%, p = 0.90) and screening time (OR: 0.13, 95% CI: 0.08 to 0.35, I2= 0%, p = 0.22) between the two groups. The interventional cardiology laboratory is exposed to significantly less scatter radiation during procedures owing to the RADPAD protective drape. Consequently, all catheterization laboratories could be advised to employ RADPAD protective drapes.

Potential risk assessment: a model for quality evaluation in fluoroscopy-guided interventional procedures.

This study presented a model applied for potential risk assessment in an interventional radiology setting. The model of potential risk assessment (MARP) consisted of the creation of a scale of indicators ranging from 0 to 5. The radiation levels were categorized according to gender, kind of procedure, value of kerma air product (Pka), and accumulated radiation dose (mGy). The MARP model was applied in 121 institutions over 8 y. A total of 201656 patient radiation doses (Dose-area product and accumulated kerma) data were launched into the system over time, with an average of 22406 doses per year. In the context of the workers (cardiologists, radiographers, and nurses) monitored during the MARP application, 8007 cases (with an average of 890 per year) of occupational radiation doses were recorded. This study showed a strategy for quality evaluation in fluoroscopy using a model with a compulsory information system for monitoring safety.

Dose optimization in newborn abdominal radiography: Assessing the added value of additional filtration on radiation dose and image quality using an anthropomorphic phantom

BackgroundAbdominal radiographs remain useful in newborns. Given the high radiation sensitivity of this population, it is necessary to optimize acquisition techniques to minimize radiation exposure. ObjectiveEvaluate the effects of three additional filtrations on radiation dose and image quality in abdominal X-rays of newborns using an anthropomorphic phantom. Material and methodAbdominal radiographs of an anthropomorphic newborn phantom were performed using acquisition parameters ranging from 55 to 70 kV and from 0.4 to 2.5 mAs, without and with three different additional filtrations: 0.1 mm copper (Cu) + 1 mm aluminum (Al), 0.2 mm copper + 1 mm aluminum, and 2 mm aluminum. For each X-ray the dose area product (DAP) was measured, the signal-to-noise ratio (SNR) was calculated, and image quality (IQ) was evaluated by two blinded radiologists using the absolute visual grading analysis (VGA) method. ResultsAdding an additional filtration resulted in a significant reduction in DAP, with a decrease of 42% using 2 mm Al filtration, 65% with 0.1 mm Cu + 1 mm Al filtration, and 78% with 0.2 mm Cu + 1 mm Al filtration (p < 0.01). The addition of 2 mm aluminum filtration does not significantly decrease the SNR (p = 0.31), CNR (p = 0.52) or the IQ (p = 0.12 and 0.401 for reader 1 and 2, respectively). However, adding copper-containing filtration leads to a significant decrease in, SNR, CNR and IQ. ConclusionAdding a 2 mm Al additional filtration for abdominal radiographs in newborns can significantly reduce the radiation dose without causing a significant decrease in image quality.

An audit of patient radiation doses during interventional cardiology procedures in Uttarakhand, India, and establishment of local diagnostic reference levels.

The objective of this study was to investigate patient radiation doses by a dose audit of three common interventional cardiology (IC) procedures: coronary angiography (CA), percutaneous transluminal coronary angioplasty (PTCA) and CA-PTCA procedures performed in IC centres in the Uttarakhand state of India, for the establishment of local diagnostic reference levels (DRLs) and the estimation of average effective dose (Eav) for these procedures. For each procedure, the values of kerma-area product (PKA), reference air kerma (Ka,r), fluoroscopy time (FT) and the number of cine images were recorded from 1233 CA, 458 PTCA and 736 CA-PTCA procedures performed over a 12-month period at 13 IC centres of the state. From the recorded dose data, 0.6%, 1.53% and 7.9% patients were identified to have exceeded the PKA trigger level of 500 Gy cm2 for possible skin injury for CA, PTCA and CA-PTCA procedures, respectively. The 3rd quartile of the distribution of the recorded PKA values for each type of procedure was calculated to estimate local DRL values. The estimated values of DRLs and Eav were 37, 153 and 224 Gy cm2, and 6.72, 23.97 and 34.79 mSv for CA, PTCA and CA-PTCA procedures, respectively. For about 77% of the surveyed centres, the recorded patient doses were in agreement with the international standards. The local DRLs proposed in this study may be used to achieve patient dose optimization during IC procedures and the obtained patient dose data may also be archived into national dose database for the establishment of national DRLs.

Retrospective case-control study on radiation dose for uterine artery embolization procedures.

Uterine artery embolization is performed in pre-menopausal women. Understanding the contribution of radiation dose at each stage of the procedure is important for potential dose reduction. The aim was to retrospectively analyse radiation dose on a per-procedural-stage basis, comparing digital subtraction angiography (DSA) and conventional roadmap (CRM). Group A consisted of 50 patients where DSA was used for road mapping at all stages: (I) Aortogram, (II) Left internal iliac artery (IIA) DSA, (III) Left uterine artery (UA) DSA, (IV) Right IIA DSA and (V) Right UA DSA. Group B included 50 patients, where CRM was used for road mapping at stages (II) and (IV). For Group A, mean total dose-area product (DAP) was 39.7 Gy·cm2; mean DAP for each stage were (I) Aortogram = 3.4 Gy·cm2, (II) Left IIA DSA = 5.9 Gy·cm2, (III) Left UA DSA = 3.2 Gy·cm2, (IV) Right IIA DSA = 5.5 Gy·cm2 and (V) Right UA DSA = 3.0 Gy·cm2. For Group B, mean total DAP was 33.6 Gy·cm2, mean DAP for each stage were (I) Aortogram = 3.3 Gy·cm2, (II) Left IIA CRM = 1.5 Gy·cm2, (III) Left UA DSA = 3.3 Gy·cm2, (IV) Right IIA CRM = 1.5 Gy·cm2 and (V) Right UA DSA = 3.3 Gy·cm2. Fluoroscopy time was 10 and 9.4 min for Groups A and B, respectively. The highest road-mapping radiation dose contribution was from bilateral IIA DSA. The use of CRM, intermittent fluoroscopy and elimination of the aortogram is recommended to further reduce procedural radiation dose.

Meta-analysis of transjugular intrahepatic portosystemic shunt creation with or without intravascular ultrasound guidance.

To conduct a meta-analysis to assess the efficacy of intravascular ultrasound (IVUS) during transjugular intrahepatic portosystemic shunt (TIPS) creation. MEDLINE and Embase databases were queried until July 2022 for comparative studies reporting procedure metrics for TIPS creation with or without IVUS guidance. Meta-analysis was performed with random-effects modelling for total procedural time, time to portal venous access, fluoroscopy time, iodinated contrast volume use, air kerma, dose area product, and number of needle passes. Intraoperative procedure-related complications were also reviewed. Of 95 unique records initially identified, 6 were eligible for inclusion. A total of 194 and 240 patients underwent TIPS with and without IVUS guidance. Pooled analyses indicated that IVUS guidance was associated with reduced total procedure time (SMD -0.76 [95% CI -1.02, -0.50] P < .001), time to portal venous access (SMD -0.41 [95% CI -0.67, -0.15] P = .002), fluoroscopy time (SMD, -0.54 [95% CI -1.02, -0.07]; P = .002), contrast volume use (SMD, -0.89 [95% CI -1.16, -0.63]; P < .001), air kerma (SMD, -0.75 [95% CI -1.11, -0.38]; P < .001) and dose area product (SMD, -0.98 [95% CI -1.77, -0.20]; P = .013). A total of 4.2 and 7.8 needle passes were required in the IVUS and non-IVUS group, respectively (SMD, -0.60 [95% CI -1.42, 0.21]; P = .134). Pooled complication rates were 15.2% (12/79) and 21.4% (28/131), respectively. IVUS guidance during TIPS creation improves procedural metrics including procedural time, contrast usage, and radiation exposure. (1) The use of IVUS during TIPS is associated with shorter procedural time, lower contrast usage, and radiation exposure. (2)The use of IVUS is not associated with higher complication rates.

Low-dose CT: A safe and effective imaging modality in post-operative pelvic & acetabular fixation

IntroductionPost-operative pelvic & acetabular fixation patients are conventionally imaged using 3-view radiographs (AP, inlet and outlet). The efficacy of such radiographs is inconsistent due to technical difficulties capturing an adequate view, often necessitating repeat radiographs and therefore increasing radiation exposure. Radiographs can be difficult to interpret, limiting the assessment of fracture reduction and fixation, especially with respect to metalwork positioning around articular surfaces. Traditionally, post-operative pelvic & acetabular fixation patients undergo repeat 3-view radiographs post-operatively, at 6 weeks, followed by at 3, 6, 12, 18 and 24 months. We propose a new pathway, in which patients have one low-dose pelvic CT immediately post-operatively, followed by one radiograph (AP pelvis) at the same time points. MethodsA new pelvic CT protocol was created to provide high quality 3D imaging whilst delivering a 5 times lower radiation dose (compared to normal pelvic CT). Data for all pelvic radiographs and CTs between January 2021 and March 2022 was exported. Using dose area product values, effective radiation dose and attributable lifetime cancer risk were calculated. ResultsThere were 42 patients included in the analysis (age range 15 to 87).The average effective dose for the 3-view pelvic X-rays was 0.6mSv (range 0.2 to 2.8mSv), and 1.1mSv (range 0.5 to 2.2mSv) for the low-dose pelvic CT. Traditional 7 × 3-view post-operative radiographs: 7 × 0.6mSv = 4.2mSv (corresponding to 1 in 11,000 cancer risk) Low dose post-operative CT and 6 × 1-view radiographs: 1.1mSv + (6 × 0.6mSv / 3) = 2.3mSv (corresponding to 1 in 20,000 cancer risk) ConclusionLow-dose CT scanning (in conjunction with 1-view radiographs) is an effective and safe imaging modality in the post-operative assessment of pelvic & acetabular fracture fixation, conferring a lower radiation burden, easier logistics, and higher quality images when compared to the traditional pathway of 3-view radiographs.

Towards the establishment of national diagnostic reference levels for abdomen, KUB, and lumbar spine x-ray examinations in Sri Lanka: a multi-centric study

Diagnostic reference levels (DRLs) and achievable doses (ADs) provide guidance to optimise radiation doses for patients undergoing medical imaging procedures. This multi-centre study aimed to compare institutional DRLs (IDRLs) across hospitals, propose ADs and multi-centric DRLs (MCDRLs) for four common x-ray examinations in Sri Lanka, and assess the potential for dose reduction. A prospective cross-sectional study of 894 adult patients referred for abdomen anteroposterior (AP), kidney-ureter-bladder (KUB) AP, lumbar spine AP, and lumbar spine lateral (LAT) x-ray examinations was conducted. Patient demographic information (age, sex, weight, BMI) and exposure parameters (tube voltage, tube current-exposure time product) were collected. Patient dose indicators were measured in terms of kerma-area product (PKA) using a PKA meter. IDRLs, ADs, and MCDRLs were calculated following the International Commission on Radiological Protection guidelines, with ADs and MCDRLs defined as the 50th and 75th percentiles of the median PKA distributions, respectively. IDRL ranges varied considerably across hospitals: 1.42–2.42 Gy cm2 for abdomen AP, 1.51–2.86 Gy cm2 for KUB AP, 0.83–1.65 Gy cm2 for lumbar spine AP, and 1.76–4.10 Gy cm2 for lumbar spine LAT. The proposed ADs were 1.82 Gy cm2 (abdomen AP), 2.03 Gy cm2 (KUB AP), 1.27 Gy cm2 (lumbar spine AP), and 2.21 Gy cm2 (lumbar spine LAT). MCDRLs were 2.24 Gy cm2 (abdomen AP), 2.40 Gy cm2 (KUB AP), 1.43 Gy cm2 (lumbar spine AP), and 2.38 Gy cm2 (lumbar spine LAT). Substantial intra- and inter-hospital variations in PKA were observed for all four examinations. Although ADs and MCDRLs in Sri Lanka were comparable to those in the existing literature, the identified intra- and inter-hospital variations underscore the need for dose reduction without compromising diagnostic information. Hospitals with high IDRLs are recommended to review and optimise their practices. These MCDRLs serve as preliminary national DRLs, guiding dose optimisation efforts by medical professionals and policymakers.

Optimization of radiation doses for open lumbar spinal fusion using C-arm fluoroscopy and impact on radiation-induced cancer: a pilot study.

Intraoperative fluoroscopy use is essential during spinal fusion procedures. The amount of radiation dose should always be minimized. This study aimed to determine the feasibility of halving the frame rate from 12.5 to 6.25 frames per second (fps) and to quantify the reduction in the risk of developing radiation-induced cancer. This pilot study included 34 consecutive patients operated for open lumbar posterolateral fusion (PLF) with or without transforaminal lumbar interbody fusion (TLIF). C-arm modes were changed from half-dose (12.5 frames per second (fps), group I) to quarter-dose (6.25fps, group II). Age, body mass index, surgical procedure, number of treated levels, and complications were collected. Kerma area product (KAP), cumulative air kerma (CAK), and fluoroscopy time were compared. Effective dose and radiation-induced cancer risk were estimated. Eighteen and 16 patients were, respectively, included in group I and II. Demographic, surgical data, and fluoroscopy time were similar in both groups. However, CAK, KAP, and effective dose were significantly lower in group II, respectively, 0.56 versus 0.41mGy (p = 0.03), 0.09 versus 0.06Gycm2 (p = 0.04), and 0.03 versus 0.02mSv (p = 0.04). Radiation-induced cancer risk decreased by 47.7% from 1.49 × 10-6 to 7.77 × 10-7 after optimization. No complications were recorded in either group. This study demonstrates the feasibility of setting 6.25fps for TLIF with and without PLF. By halving the fps, radiation-induced cancer risk could be almost divided by two, without compromising surgical outcome. Finally, after optimization, the risk of developing radiation-induced cancer was less than one in a million.

Value of magnetic resonance angiography before prostatic artery embolization for intervention planning

Knowledge about anatomical details seems to facilitate the procedure and planning of prostatic artery embolization (PAE) in patients with symptomatic benign prostatic hyperplasia (BPS). The aim of our study was the pre-interventional visualization of the prostatic artery (PA) with MRA and the correlation of iliac elongation and bifurcation angles with technical success of PAE and technical parameters. MRA data of patients with PAE were analysed retrospectively regarding PA visibility, PA type, vessel elongation, and defined angles were correlated with intervention time, fluoroscopy time, dose area product (DAP), cumulative air kerma (CAK), contrast media (CM) dose and technical success of embolization. T-test, ANOVA, Pearson correlation, and Kruskal–Wallis test was applied for statistical analysis. Between April 2018 and March 2021, a total of 78 patients were included. MRA identified the PA origin in 126 of 147 cases (accuracy 86%). Vessel elongation affected time for catheterization of right PA (p = 0.02), fluoroscopy time (p = 0.05), and CM dose (p = 0.02) significantly. Moderate correlation was observed for iliac bifurcation angles with DAP (r = 0.30 left; r = 0.34 right; p = 0.01) and CAK (r = 0.32 left; r = 0.36 right; p = 0.01) on both sides. Comparing the first half and second half of patients, median intervention time (125 vs. 105 min.) and number of iliac CBCT could be reduced (p < 0.001). We conclude that MRA could depict exact pelvic artery configuration, identify PA origin, and might obviate iliac CBCT. Vessel elongation of pelvic arteries increased intervention time and contrast media dose while the PA origin had no significant influence on intervention time and/or technical success.

Factors associated with increased radiation exposure in the fixation of proximal femoral fractures.

When using radiation intraoperatively, a surgeon should aim to keep the radiation dose as low as is reasonably achievable to obtain the therapeutic goal. We aimed to investigate factors associated with increased radiation exposure in fixation of proximal femur fractures. We assessed 369 neck of femur fractures over a 1-year period in a district general hospital. All hip fracture subtypes that had undergone surgical fixation were included. We assessed the relationship between type of fracture, implants used and surgeon level of experience with the dose-area product (DAP; cGy/cm2) and screening time (dS). We also looked at the quality of reduction and fixation and its effect on the radiation exposure. A total of 184 patients were included in our analysis; 185 patients who were treated with hip arthroplasty were excluded. There was a significant association between higher DAP and fracture subtype (p = 0.001), fracture complexity (p < 0.001), if an additional implant was used (p = 0.001), if fixation was satisfactory (p = 0.002) and operative time (p < 0.001). DAP was higher with a proximal femoral nail than with a dynamic hip screw, especially when a long nail was used. There was some evidence of an association between the surgeon's level of experience and DAP exposure, although this was not statistically significant (p = 0.069). Increased radiation in proximal femur fractures is seen in the fixation of complex fractures, some subtypes, with certain types of implants used and if an additional implant was required. Surgeon seniority did not result in less radiation exposure, which is in contrast to other published studies.

Dose-area product reduction through a practice implementing low frame rate fluoroscopy and increased collimation during single-vessel percutaneous coronary interventions

Abstract This study aims to investigate the impact of lowering fluoroscopic frame rate and increasing collimation on dose area product (DAP) during single-vessel percutaneous coronary interventions. Two patient groups that underwent such procedures were retrospectively reviewed: one treated with a standard practice employing fluoroscopy at 15 frames/s and usual collimation (standard group), and the other with a reduced practice employing fluoroscopy at 7.5 frames/s and increased collimation (reduced group). DAP, patient’s effective dose (ED), fluoroscopy time, and number of cineangiography (cine) frames were compared between groups. Multilinear analysis was performed, with DAP as a primary endpoint, to assess the impact of reduced practice in comparison to that of other variables deemed as key descriptors of radiation, patient, disease, or procedure. Relative to the standard group, the reduced group showed a significant decrease of ~37% in DAP (91.46 ± 45.08 Gy•cm2 vs. 145.23 ± 59.67 Gy•cm2, P &lt; 0.0001) and of ~39% in ED (18.70 ± 9.00 mSv vs. 30.61 ± 12.72 mSv, P &lt; 0.0001). While fluoroscopic time was not statistically different between groups (reduced: 10.3 ± 5.6 min vs. standard: 11.1 ± 5.3 min, P = 0.09), number of cine frames was significantly higher in the reduced (1162 ± 304 vs. 936 ± 363, P &lt; 0.0001) due to interoperator experience variability. Multilinear analysis demonstrated that the adoption of the reduced practice was the most significant contributor to the observed DAP decrease. After adjusting for potential confounders, a reduction of ~39% in DAP was found.

320 Intraoperative Angiography in Neurosurgery: Temporal Trend, Access Site, and Operative Indication Considerations From a Six-year Institutional Experience

INTRODUCTION: Historically, the transfemoral approach (TFA) has been the most common access site for cerebral intraoperative angiogram (IOA). However, in line with trends in cardiac interventional vascular access preferences, transradial approach (TRA) and transulnar approach (TUA) are gaining popularity due to favorable safety and patient satisfaction outcomes. METHODS: Between July 2016 and December 2022, 317 angiograms were included based on our case definition, comprising 59 TRA cases, 11 TUA cases, 243 TFA, and four transpopliteal cases. Fluoroscopy time, contrast dose, reference air kerma (RAK), and dose area products (DAP) per target vessel catheterized were the primary endpoints of interest. Univariate and multivariate regression analyses were conducted to evaluate predictors of elevated contrast dose and radiation exposure metrics. RESULTS: Contrast dose per vessel catheterized was significantly lower in TRA/TUA cases versus TFA cases (p = 0.001), but radiation exposure metrics did not differ between access site groups. TRA/TUA versus TFA does not significantly predict elevated levels of radiation exposure or contrast dose. Aneurysm cases were associated with significantly lower odds of elevated radiation exposure for all radiation metrics (p &lt; 0.05) whereas AVM cases had higher odds of elevated radiation exposure across all measures (p &lt; 0.01). There was a significant relationship between case number and operative indication over the study period (p &lt; 0.001) with a decrease in the proportion of cases for aneurysm treatment offset by increases in total cases for the management of AVF and AVM. CONCLUSIONS: TRA and TUA are safe and effective access site options for neurointerventional procedures and are increasingly employed. Cases using wrist access may be associated with a lower contrast dosing for patients.

Quantifying radiation exposure in the radiological investigation of non-arthritic hip pain

ABSTRACT Radiological investigations are essential for evaluating underlying structural abnormalities in patients presenting with non-arthritic hip pain. The aim of this study is to quantify the radiation exposure associated with common radiological investigations performed in assessing patients presenting with non-arthritic hip pain. A retrospective review of our institutional imaging database was performed. Data were obtained for antero-posterior, cross-table lateral, frog lateral radiographs and low-dose CT hip protocol. The radiation dose of each imaging technique was measured in terms of dose-area product with units of mGy cm2, and the effective doses (ED, mSv) calculated. The effective radiation dose for each individual hip radiograph performed was in the range of 0.03–0.83 mSv [mean dose-area product 126.7–156.2 mGy cm2]. The mean ED associated with the low-dose CT hip protocol (including assessment of femoral anteversion and tibial torsion) was 3.04 mSv (416.8 mGy cm2). The radiation dose associated with the use of CT imaging was significantly greater than plain radiographs (P &amp;lt; 0.005). Investigation of non-arthritic hip pain can lead to significant ionizing radiation exposure for patients. In our institution, the routine protocol is to obtain an antero-posterior pelvic radiograph and then a specific hip sequence Magnetic Resonance Imaging (MRI) scan which includes the assessment of femoral anteversion. This provides the necessary information in the majority of cases, with CT scanning reserved for more complex cases where we feel there is a specific indication. We would encourage the hip preservation community to carefully consider and review the use of ionizing radiation investigations.

Comparing Radiation Doses in CBCT and Medical CT Imaging for Dental Applications.

Dental imaging plays a crucial role in diagnosis and treatment planning, with cone-beam computed tomography (CBCT) and medical computed tomography (CT) being two common modalities. This study aims to compare the radiation doses associated with CBCT and medical CT imaging in dental applications to assess their relative safety and efficacy. We conducted a retrospective study using data from 100 patients who underwent both CBCT and medical CT scans for dental purposes. The radiation doses were measured in terms of dose-length product (DLP) for medical CT and dose-area product (DAP) for CBCT. The effective dose (ED) was calculated using appropriate conversion factors. Patient demographics, scan parameters, and radiation doses were recorded and analyzed. The results indicated that the mean DLP for medical CT scans was 220 mGycm, whereas the mean DAP for CBCT scans was 150 mGycm². The corresponding mean effective doses for medical CT and CBCT were 2.5 mSv and 1.8 mSv, respectively. The radiation dose from CBCT was found to be approximately 28% lower than that from medical CT. This study demonstrates that CBCT imaging for dental applications results in significantly lower radiation doses compared to medical CT. While both modalities provide valuable diagnostic information, the choice of imaging technique should consider the balance between diagnostic quality and radiation exposure, especially for pediatric and high-risk patients. Dental practitioners should be aware of the potential dose reduction benefits associated with CBCT when appropriate for the clinical scenario.

Technical note: A comparison of physician doses in C-Arm and CT fluoroscopy procedures.

We address the misconception that the typical physician dose is higher for CT fluoroscopy (CTF) procedures compared to C-Arm procedures. We compare physician scatter doses using two methods: a literature review of reported doses and a model based on a modified form of the dose area product (DAP). We define thismodified form of DAP, "cumulative absorbed DAP," as the product of the area of the x-ray beam striking the patient, the dose rate per unit area, and the exposure time. The patient entrance dose rate for C-Arm fluoroscopy (0.2mGy/s) was found to be 15 times lower than for CT fluoroscopy (3mGy/s). A typical beam entrance area for C-Arm fluoroscopy reported in the literature was found to be 10.6×10.6cm (112cm2), whereas for CTF was 0.75×32cm (24cm2). The absorbed DAP rate for C-Arm fluoroscopy (22mGy*cm2/s) was found to be 3.3 times lower than for CTF (72mGy*cm2/s). The mean fluoroscopy time for C-Arm procedures (710s) was found to be 21 times higher than for CT fluoroscopy procedures (23s). The cumulative absorbed DAP for C-Arm procedures was found to be 9.4 times higher when compared to CT procedures (1.59 mGy*m2 vs. 0.17 mGy*m2). The higher fluoroscopy time in C-Arm procedures leads to a much lower cumulative DAP (i.e., physician scatter dose) in CTF procedures. This result can inform interventional physicians deciding on whether to perform inter-procedural imaging inside the room as opposed to retreating from the room.

The Effect of the Use of Activation 3D Mapping on the Patient X-Ray Load During Radiofrequency Ablation of Typical Atrial Flutter

Supraventricular macro re-entry tachyarrhythmias occupy the leading places among all types of tachyarrhythmias. The most common in this category is typical atrial flutter (AFL). This heart rhythm disorder has a negative impact on the patients’ quality of life. Its complications can lead to disability and death due to possible thromboembolism. Therapeutic treatment is limited in effectiveness. The main method of intervention is catheter radiofrequency ablation (RFA). The standard approach of RFA of AFL is performed without the use of navigation systems under fluoroscopy guidance. However, this results in an increased radiation exposure to the patient and the medical personnel. Modern technologies in the field of invasive electrophysiology make it possible to create anatomical models of heart and reproduce the spread of electrical excitation. However, the routine use of additional navigation methods remains controversial.&#x0D; The aim. To compare the duration of RFA of typical AFL and radiation exposure with the use of anatomical and propagation mapping.&#x0D; Materials and methods. This study is based on the analysis of the treatment results obtained for 53 patients at the National Amosov Institute of Cardiovascular Surgery in the period from 2014 to 2023. Depending on imaging methods, the patients were divided into two groups. The first group included 27 patients with an anatomical mapping of the right atrium. The second group included 26 patients with propagation mapping.&#x0D; Results. In all the patients we have achieved a bidirectional conduction block through cavotricuspid isthmus. In the first group, the total duration of confirming the diagnosis and creating the anatomical model was 312 ± 26 seconds. The mean time to the moment of AFL termination and restoration of sinus rhythm was 230 ± 19 seconds. The average duration of the procedure was 41.5 ± 3.5 minutes, the average fluoroscopy time was 120 ± 10 seconds, the average dose area product (DAP) was 15 ± 1.3 Gy·cm2. In the second group, the average time for creating a 3D propagation model of right atrium and verifying the diagnosis was 748 ± 65 seconds. The average time from the first application to the termination of tachycardia was 227 ± 20 seconds. The average duration of the procedure was 55 ± 4.7 minutes, X-ray time was 93 ± 8 seconds, average DAP was 13 ± 1.1 Gy·cm2. The duration of the procedure in the second group was significantly longer (p = 0.03), however, the radiation exposure and DAP were not statistically different (p = 0.31) between the observation groups.&#x0D; Conclusions. The use of propagation mapping increases the time of the procedure by 24.5% and does not give a significant advantage in reducing the radiation exposure. The use of a navigation system during cavotricuspid isthmus RFA is recommended for concomitant radical treatment of complex supraventricular arrhythmias, such as atrial fibrillation.