Radiation-based indicators for ERCP quality evaluation.

The American Association of Physicists in Medicine (AAPM) is a nonprofit professional society whose primary purposes are to advance the science, education, and professional practice of medical physics. The AAPM has more than 8,000 members and is the principal organization of medical physicists in the United States. The AAPM will periodically define new practice guidelines for medical physics practice to help advance the science of medical physics and to improve the quality of service to patients throughout the United States. Existing medical physics practice guidelines will be reviewed for the purpose of revision or renewal, as appropriate, on their fifth anniversary or sooner. Each medical physics practice guideline represents a policy statement by the AAPM, has undergone a thorough consensus process in which it has been subjected to extensive review, and requires the approval of the Professional Council. The medical physics practice guidelines recognize that the safe and effective use of diagnostic and therapeutic radiology requires specific training, skills, and techniques, as described in each document. Reproduction or modification of the published practice guidelines and technical standards by those entities not providing these services is not authorized. Must and Must Not: Used to indicate that adherence to the recommendation is considered necessary to conform to this practice guideline. While must is the term to be used in the guidelines, if an entity that adopts the guideline has shall as the preferred term, the AAPM considers that must and shall have the same meaning. Should and Should Not: Used to indicate a prudent practice to which exceptions may occasionally be made in appropriate circumstances. Fluoroscopy equipment is used to observe or guide moving objects such as internal organs, contrast agents, catheters, and guidewires within the body to diagnose and treat disease. Procedure times range from several seconds to multiple hours, and fluoroscopes range from small, mobile C-arms used to image extremities, to complex single- or bi-plane angiography systems. These more complex fluoroscopes are used to guide performance of fluoroscopically guided interventional (FGI) procedures, and help to provide lifesaving diagnostic and therapeutic services for patients. However, unlike simpler procedures commonly accomplished using general or mobile C-arm fluoroscopes, long and complex FGI procedures can exceed radiation thresholds for tissue reactions. Proper identification, follow-up, and management of patients receiving high doses from FGI procedures are essential parts of patient care due to the slowly developing nature of radiation-induced tissue reactions. Recent standards and requirements from accrediting bodies such as The Joint Commission (TJC) and state regulatory agencies have brought focus to this issue, requiring hospitals to record patient fluoroscopy exam dose indices and to establish committees, policies, and procedures for reviewing those data and providing patient follow-up as appropriate. These standards are in addition to TJC's updated fluoroscopy sentinel event standard, which requires identification and investigation of severe tissue effects. Many organizations and societies have provided guidance and resources for managing patient dose, including the National Council on Radiation Protection and Measurements (NCRP), the Conference of Radiation Control Program Directors (CRCPD), the Department of Veterans Affairs, the Society of Interventional Radiology (SIR), and multiple cardiology societies under the umbrella of the American College of Cardiology Task Force on Expert Consensus Decision Pathways.1–5 This AAPM practice guideline aims to outline the role of the diagnostic qualified medical physicist (QMP), as defined by AAPM Policy Number PP 1-J "Definition of A Qualified Medical Physicist," in practical patient dose management for FGI procedures.6 This role includes helping facilities set up policies related to dose management, including pre-procedure patient consent, intra-procedure dose index level notification, and post-procedure follow-up for potential tissue reactions. Suggestions for methods of complying with TJC standards and various state regulatory requirements for tracking radiation use, setting dose index thresholds, and analyzing dose index data are provided, along with a discussion of the challenges posed by these requirements. The QMP's role in helping facilities comply with TJC's updated "radiation overdose" sentinel event standards by investigating severe tissue reactions is also discussed. Related fluoroscopy topics that may fall under the QMP's oversight, such as operator credentialing and occupational radiation exposure monitoring are briefly discussed. Tissue reactions, also known as deterministic effects, are due to radiation effects on populations of cells and are characterized by a threshold dose and an increase in the severity of the reaction with increasing dose.7 These reactions are the primary concern for patients undergoing FGI procedures, and will be the focus of this report, with stochastic risks not being addressed. Tissue reactions do not occur at doses below a threshold dose, which the International Commission on Radiological Protection (ICRP) defines as the dose estimated to result in a 1% incidence of the tissue reaction.8 Tissue reactions in patients undergoing FGI procedures may involve skin, hair, subcutaneous fat, muscle, the lens of the eye, and sometimes bone.9, 10 The generally accepted minimum threshold dose for transient skin effects is an absorbed skin dose of approximately 2 Gy, and permanent effects are unlikely below an absorbed skin dose of 5 Gy.1, 11 Risks for tissue reaction can conservatively be assumed as cumulative when the same skin area has been irradiated for other procedures. Repair of sublethal radiation injury to skin is typically complete within a day of exposure; repopulation of cells can require months.11 Tissue reactions may be expressed days to years after exposure, depending on the radiation dose and the tissue affected. Early reactions may be due to inflammation, and may not be noticed by the patient, whereas late reactions are typically due to cell loss. Tissue reactions in the skin range in severity from erythema and transient epilation to dermal necrosis, which can require surgical intervention.12 Because of individual variability in radiosensitivity, the radiation dose necessary to produce a specific effect and the time course of the tissue reaction are best thought of as ranges, rather than specific values, as shown in Table 1, reprinted from Balter et al.11 Additionally, it should be noted that previously irradiated skin is at a higher risk for developing tissue reactions than areas that have had no prior exposure. Predicting the likelihood of radiation-induced effects from FGI procedures requires an estimation of the patient's radiation dose. Four measurable radiation dose indices exist to assist with this estimation: fluoroscopy time, cumulative air kerma (Ka,r or CAK), air kerma–area product (PKA, also commonly written as KAP or dose–area product/DAP), and peak skin dose (PSD). Effective dose is not suitable for assessing the likelihood of tissue effects. The availability and displayed units of each dose index vary depending on equipment type, manufacturer, and equipment age, and each differs in clinical utility and application. Fluoroscopy time is the most widely available index; however, it is also the least useful in terms of predicting potential tissue effects. Fluoroscopy time alone is inadequate to estimate patient dose. It does not consider fluoroscopic dose rate, and dose estimates that rely solely on fluoroscopy time can vary widely, as acquisitions (e.g., cine, Digital Subtraction Angiography (DSA)), which can contribute substantial dose, are not included in the measurement.13 If additional dose rate and dose per image data are available for the specific mode of operation used, using the number of fluorographic images from a procedure, along with fluoroscopy time, can improve estimations of patient dose. However, while fluoroscopy time is suboptimal for assessing radiation dose, it can be useful for other purposes (e.g., a surrogate for procedure complexity and comparing practice among operators). CAK (Ka,r) is required to be displayed on all International Electrotechnical Commission (IEC) compliant interventional fluoroscopes and all fluoroscopes sold in the United States since June 2006.4, 14, 15 Ka,r is the cumulative kerma for a fluoroscopic procedure, including fluoroscopic and acquisition modes of operation, measured in air at a specific reference point relative to the X-ray source. For isocentric C-arms, the IEC definition for the reference point is along the central ray of the X-ray beam, 15 cm from the isocenter toward the X-ray tube, though manufacturers can use a different reference point if they choose. The specific reference point used by a piece of equipment is defined in the operator's manual. Ka,r is often used as a surrogate for the patient's PSD; however, potentially labor-intensive corrections and calculations are required if a more accurate estimate of PSD is needed. These corrections include backscatter, table and pad attenuation, displayed dose index accuracy, and tissue-to-air ratio. Additionally, due to beam geometry, gantry angulation, table height, and patient size, the reference point may not coincide with the entrance skin surface. This results in a tendency for Ka,r to overestimate PSD. Despite these shortcomings, Ka,r is generally considered a practical surrogate for skin dose.2 Ka,r is almost universally reported in units of milligray (mGy) in modern fluoroscopes. KAP (PKA), sometimes called DAP, is the product of air kerma and the geometric area irradiated in the same plane orthogonal to the propagation of the X-ray beam. PKA displays are widely available on interventional fluoroscopes and commonly available on many modern mobile C-arms and conventional diagnostic fluoroscopy equipment. Unlike Ka,r, PKA is independent of distance from the focal spot, because the irradiated area increases proportionally to the decreased radiation intensity as distance increases. Therefore, small doses to a large area and large doses to a small area could give equal PKA values. For this reason, PKA is considered a poor indicator of skin dose and radiation-induced tissue effects. Because PKA represents the total energy deposited in the patient, it is better correlated to stochastic risk as compared with Ka,r. Additionally, a lack of standardized units for displayed PKA values on fluoroscopic equipment can make the practical implementation of clinical thresholds difficult. PKA displayed units of uGy × m2, mGy × cm2, cGy × cm2, and Gy × cm2 are all in use. PSD indicators, with real-time dose mapping displays, are the least common dose index available at present but are becoming increasingly common on modern FGI equipment. They allow the operator to visualize the three-dimensional skin dose distribution, potentially preventing tissue reactions. Freestanding software, independent of the FGI equipment, is also available that can estimate PSD based on data provided in the radiation dose structured report (RDSR). Real-time PSD information provides the greatest clinical utility for predicting the likelihood of tissue reactions because it provides estimates of the highest skin dose and its location using information on patient position, X-ray field size, and beam angulation during a procedure. Freestanding software that reconstructs PSD from RDSR information also has clinical utility but lacks direct feedback to the operator during a procedure. It is important to be aware of manufacturer-specific approaches to PSD estimates and their level of sophistication with regard to inclusion of correction factors such as backscatter, table and table pad attenuation, and patient anatomical representation. Because of these differences in approach, it is possible that fluoroscopes from different manufacturers, or even different versions of the same manufacturer's software, could provide different PSD values given identical RDSRs. A review of various PSD software options was presented by Malchair et al.16 At present, real-time PSD estimates are limited to FGI fluoroscopes and are not found on mobile C-arms or general fluoroscopic equipment. PSD is commonly reported in units of milligray (mGy). In setting up a patient fluoroscopy dose management program, the QMP will need to survey the dose indices available on the imaging equipment in a facility or larger healthcare system. The availability of these indices will determine the dose index used to set thresholds for further action. Some dose indices may be available but require equipment configuration in order to be displayed. For older equipment that does not display Ka,r or PKA, aftermarket meters can provide this capability. Ideally, one would use PSD, the dose index that best correlates with potential tissue injury, but its limited availability and the variability in assumptions and corrections made by PSD algorithms complicate its use at the present time. Due to its standard definition, ubiquitous implementation, and reasonable correlation with PSD, it is the recommendation of this group that CAK (Ka,r) be the primary dose index used in setting fluoroscopic threshold dose levels for notification and patient follow-up. Pre-procedure screening and consent of the patient. Intra-procedure monitoring and notification of patient dose index level to the team. Post-procedural patient follow-up above threshold levels. While QMPs are not typically involved in the day-to-day implementation of these policies and procedures, their expertise is critical in development of the policies. Additionally, the QMP can be consulted when specific questions arise and may be called upon for PSD or other dose estimates. Each healthcare facility must create a policy for obtaining a radiation-specific consent from patients prior to FGI procedures where patients are given information regarding the risks of radiogenic tissue effects. Whenever possible, this policy should be standardized across all departments utilizing FGI equipment across the entire organization. Local laws may dictate whether consent can be verbal or must be written. A facility may choose to obtain this consent before all procedures performed in FGI suites or only before a subset of procedures classified as potentially high dose. The QMP can aid in reviewing facility data to determine which procedures require consent. NCRP Report No. 168 suggests classifying procedures as "potentially high radiation dose procedures" if more than 5% of procedures result in Ka,r exceeding 3 Gy.1 Obtaining a radiation consent for only a subset of procedures removes a clinical step prior to procedures where tissue effects are highly unlikely. However, it may complicate policy and process by requiring someone to create and keep updated a list of procedures in radiology, cardiology, surgery, and other specialties requiring radiation consent. An example of simple radiation consent language, adapted from the SIR's guidelines for patient dose management, can be found in Appendix A.17 Additional example consent language can be found in NCRP Report Nos. 168 and 185.1, 18 Any such document should be reviewed by appropriate clinical and legal teams prior to implementation. Key elements of consent language should include a description of the use of X-rays in fluoroscopy, the possible tissue effects resulting from prolonged exposure to X-rays, the typical time delays for these effects to occur, and the proposed action(s) for the patient and/or caregiver if any effect is observed. In addition to screening for potential medical issues or pregnancy, patients who will undergo potentially high-dose FGI procedures should be screened to determine if they are at higher risk for tissue effects. The result of pre-procedure patient screening is then conveyed to the performing physician. Patients at higher risk include those who have had recent high-dose fluoroscopy procedures or a history of radiation therapy to the same skin area, collagen vascular disease, or certain genetic disorders that affect DNA repair, which are further detailed in Ref.11 High body mass index (BMI) is also a risk factor since the greater amount of tissue increases the amount of radiation needed to yield an adequate image and can result in the skin being closer to the X-ray source.19 Intra-procedural notifications regarding radiation dose levels allow the performing physician to gauge the benefit–risk ratio at each stage of an FGI procedure. All FGI procedures should be justified, that is, offer a clinical benefit to the patient greater than the potential risks, which include radiation tissue reactions.1 This benefit–risk ratio is considered by the physician when initially deciding whether to perform a procedure, and later, while the procedure is in progress. For the benefit–risk ratio to be meaningful, the physician needs to have an accurate understanding of radiation risk, the likelihood of tissue injury, and the associated dose–response relationship.11 The QMP, as the subject matter expert in this area, can provide radiation protection planning knowledge to the team to help ensure that the benefit–risk ratio is formulated correctly. The QMP must also understand the magnitude of radiation risk compared to other procedural risks, which are often much greater than the risk of tissue reaction. The risk of a radiation effect is typically much smaller than other procedural risks, such as bleeding, infection, and organ damage. However, the benefit–risk ratio is not static, and may change during the procedure. This analysis should be performed by a well-informed operator and should be evaluated throughout the procedure. Procedures should rarely, if ever, be stopped solely due to radiation dose. If all or most progress made during the procedure is lost if the procedure is stopped (e.g., navigation of catheter to a very difficult site, or risk of developing collateral vasculature in the interval), any risks already incurred will have been for no benefit to the patient.1 When appropriate clinically, very complex procedures may be planned in a staged fashion, with multiple sessions separated by 8–10 weeks, to fractionate the dose to the skin and reduce the likelihood of tissue reactions. The concept and implementation of radiation dose notification levels is simple. The same concept has been applied to other potentially toxic agents, such as iodine contrast or medications.1 The implementation of notification levels requires the entire procedure team to work together. For example, the radiologic technologist, who is a local expert on the operation of fluoroscopy equipment, may be the one who calls out when the notification level is reached and this in the procedure The may then document the same information in the medical while the operator or performing physician for a to consider their radiation management and the benefit–risk of the procedure. notification to the operator regarding the notification number and the magnitude of the dose for example, is the The reference air kerma is of a procedural to and the benefit–risk of the procedure, if such a will not with the of the procedure. of the notification that the operator was that the and benefit–risk ratio of the procedure and any specific by the of the patient table it is set within the range at the of the procedure, but may be during the procedure, for example, to isocenter the patient for after which the table is not to the of a large air by the image of X-ray beam and gantry of organ imaging for such as dose rate and radiation management practice often suggests that the of the gantry be during a procedure to radiation dose across the While this can be useful in specific as a it can be to radiation management and increase the skin dose rate and the PSD, in where larger increase radiation and the patient's skin closer to the If used as a radiation management of the X-ray beam increases the benefit of this real-time PSD mapping if can help determine the benefit of these of procedures on the procedure (e.g., the fluoroscopy dose notification level could be in of the Ka,r and PSD. The of the procedure the ratio of PSD to Ka,r, as the by et the as described by will be to as the in this For procedures, such as those performed in vascular and interventional radiology, the PSD is often to the reported Ka,r factor For isocentric procedures, where the is at isocenter to the use of multiple gantry the skin dose will be higher than the Ka,r if only a or a range of is used factor However, isocentric procedures often require the use of many different gantry which may result in multiple on the skin of the patient. This to reduce the dose and the PSD would be than the Ka,r factor Many interventional fluoroscopes offer the to one or more fluoroscopy dose notification levels the system. that notification an and/or a is displayed at the of the for example, a only such levels at values, this is a when the and notification levels in notification levels may be for different services based on the of procedures performed or the available dose The QMP should ensure that any dose notification levels are though this can be by differences in manufacturer's specific The fluoroscopy is often in interventional fluoroscopy because it times during most procedures. with dose notification levels is an important for the of the notification level and the notification levels. other important notification is the and correction of when they of include the of the patient's in the field of when the is not the area of and direct of the lens or tissue when of the procedural team should be in such when they exist and to the operator and physician. medical physicists can provide to their healthcare organizations only when they understand the clinical of fluoroscopically guided procedures. Fluoroscopy dose indices can only be when by the clinical of the procedure, and imaging for fluoroscopy can be only when the involved in the procedure are For these it is important that a QMP who a clinical FGI practice be provided clinical and time to observe clinical procedures, including the equipment and are used by physician It is that this time can also be used to The substantial radiation dose level is an threshold for radiation dose above which additional post-procedure for patient care should be due to the potential for The should be set to a level such that a radiation dose below the is unlikely to result in a tissue injury for an patient of radiation However, is no that a radiation level below an is safe or that a radiation level above an will an and factors such as or could the threshold to a tissue values for the are 5 Gy Ka,r or 3 Gy real-time PSD estimates are not typically available on most equipment, use of Ka,r is generally to establish thresholds for post-procedure follow-up. When setting the Ka,r the previously PSD factor concept should be If it is known that the entrance skin point is to be during a procedure or the skin is closer to the X-ray than the interventional reference point entrance reference point a may be for procedures, the dose from each plane should be for purposes it is known that the do not Each facility must have a policy for patients who a radiation dose exceeding the and for providing patient management and follow-up, including of post-procedure information written in simple This document Appendix adapted from NCRP Report No. 168 language, for an should provide information the procedure, follow-up and information for questions or This information can be provided in in the medical or of the individual for these is and should be of the or physician can be this the facility must have an for patient follow-up and must document any such in the medical may be or and may be provided by any clinical team under the of the performing physician. All tissue effects should be assumed radiogenic If a severe or prolonged radiogenic tissue reaction is the patient should be in by the performing physician possible and to radiation or appropriate for further with all appropriate information included in the patient's medical PSD estimates may be useful for patient management in should have a defined process for a PSD estimate performed by or under the of a PSD estimates required by or standard, or from a must be in the patient medical The of PSD from dose indices are the of this document and have been described Due to the various assumptions and PSD estimates are unlikely to be better than This should be included in any estimate and QMPs should include a range of possible values in addition to the PSD For example, depending on various assumptions made regarding procedure such as table height, and beam angulation, a PSD estimate could be as Gy, but with a range of of the American Medical Association a that to PSD to of radiation exposure that may be where a patient has multiple procedures in a of time where no procedure the threshold for patient follow-up, but the doses action. an appropriate time for a of doses is previously of sublethal radiation injury to skin is typically complete within a day of exposure, doses within a should be However, repopulation of cells can require The SIR's guidelines for patient dose management doses a while prior TJC sentinel event standards required doses This report days as the most time for patient skin dose. The same thresholds for follow-up should be used for or multiple cumulative procedures that exceed the patients with high doses from multiple procedures, and their potential risk, is The patient's history of radiation may be if at or even in a different

Performing endoscopic retrograde cholangiography without radiation exposure: Are we ready for it?

To determine the factors that influence radiation exposure during repair of supracondylar humerus fractures. Medical records of almost 200 children with supracondylar fractures were retrospectively analyzed for variables correlated with fluoroscopy time and radiation dose as measures of radiation exposure. There was no statistically significant difference in fluoroscopy time (27 vs. 22s p = 0.345) or direct radiation dose (0.394 vs. 0.318mSv p = 0.290) between uniplanar and biplanar C-arm use. No statistically significant differences in fluoroscopy time or radiation dose were found for surgical technique, comorbid ipsilateral fractures, preoperative neurovascular compromise, or resident participation. There was a significant 8.3s increase in fluoroscopy time (p = 0.022) and 0.249mSv increase in radiation dose (p = 0.020) as the fracture type increased from II to III. An increase in one pin during CRPP resulted in a statistically significant 10.4s increase in fluoroscopy time and a 0.205mSv increase in radiation dose. There were significant differences between the physician with the lowest fluoroscopy time and radiation dose compared with the physicians with the two highest values for both fluoroscopy time and radiation dose (p < 0.01). We found no significant difference in direct radiation exposure or fluoroscopy time when comparing biplanar to uniplanar C-arm use, resident participation, preoperative neurovascular compromise, or for comorbid ipsilateral fractures. Both outcomes increased significantly as fracture type increased from II to III and as the number of pins used during CRPP increased. Both outcomes were significantly different between the surgeons performing CRPP.

Background:Fluoroscopy is a vital imaging technique in orthopaedic surgery, particularly with the growing adoption of minimally invasive surgery (MIS). Because of their increased reliance on intraoperative imaging, MIS techniques may necessitate greater use of fluoroscopy and radiation compared with open procedures; therefore, the use of modern mini C-arm systems is recommended to mitigate radiation exposure. Although MIS offers significant benefits, its use also raises concerns regarding radiation exposure for both patients and surgical staff. This study evaluated radiation dose and fluoroscopy time comparing 2 common procedures used to treat insertional Achilles tendinitis: the percutaneous Zadek osteotomy (ZO) and the open midline Achilles tendon splitting Haglund resection (HR). We hypothesized that the percutaneous ZO would be associated with increased radiation dose and fluoroscopy time in comparison to the open HR but would be below the recommended occupational exposure limits.Methods:A retrospective review was conducted of all patients who underwent a percutaneous ZO or an open HR between January 2021 and July 2025. All procedures were performed by one of 2 fellowship-trained foot and ankle surgeons at a single academic institution. Radiation exposure was assessed using total radiation dose (mGy) and total fluoroscopy time (minutes).Results:A total of 139 patients met inclusion criteria. Sixty patients underwent a percutaneous ZO, whereas 79 underwent an open HR. The percutaneous ZO cohort demonstrated a mean fluoroscopy time of 2.83 ± 1.64 (range, 0.70-7.17) minutes and an average radiation dose of 3.25 ± 2.06 (range, 0.55-8.07) mGy. Meanwhile an average fluoroscopy time of 0.42 ± 0.19 (range, 0.03-0.90) minutes was observed in the open HR cohort, which had a mean radiation dose of 0.38 ± 0.20 (range, 0.02-1.17) mGy. The percutaneous ZO cohort demonstrated a significantly higher radiation dose (P < .001) and fluoroscopy time (P < .001).Conclusion:The percutaneous ZO was associated with a significantly higher radiation dose than the open HR; however, despite being statistically significant, this may not be clinically relevant. As surgeons receive only 0.50% of the dose, approximately 1225 percutaneous ZO procedures would be required to exceed annual safety limits. These findings suggest that radiation exposure during the percutaneous ZO technique remains well below the International Commission on Radiological Protection’s annual occupational limit of 20.00 mSv. Consistent with the ALARA principle, low-dose mini C-arm settings and protective equipment help minimize radiation exposure to patients and surgical staff.Level of Evidence:Level III, retrospective comparative study.

IntroductionAs the prevalence of neuroendovascular interventions increases, it is critical to mitigate unnecessary radiation for patients, providers, and health care staff. Our group previously demonstrated the feasibility of reducing radiation...

3340 Assessment of radiation exposure during ercp and the efficacy of the shielding board.

Intraoperative fluoroscopy has become essential in orthopaedic surgery, particularly with the rise of minimally invasive surgery (MIS) techniques. As MIS techniques depend more on intraoperative imaging, MIS techniques may necessitate increased fluoroscopy use compared with open procedures. Despite the advantages of minimally invasive foot and ankle surgery, MIS techniques raise concerns about radiation exposure to both patients and surgical staff. The purpose of this study was to evaluate fluoroscopy time and radiation dose (cumulative air kerma) associated with open versus MIS bunion correction, comparing the open modified Lapidus procedure and the minimally invasive distal first metatarsal transverse osteotomy and akin osteotomy (META). It was hypothesized that the META procedure would be associated with increased radiation dose and fluoroscopy time compared with the open modified Lapidus procedure. A retrospective review was conducted for patients who underwent bunion surgery between January 2021 and June 2025 by two fellowship-trained orthopaedic foot and ankle surgeons at a single academic institution. A total of 294 patients met inclusion criteria. Of these, 258 patients underwent a META procedure and 36 underwent an open modified Lapidus procedure. Fluoroscopy time (minutes) and radiation dose (mGy) were compared between the groups. A mean fluoroscopy time of 2.13 ± 1.27 (range, 0.06 to 7.05) minutes and a radiation dose of 2.02 ± 1.30 (range, 0.05 to 7.52) mGy were observed in the META cohort. An average fluoroscopy time of 1.63 ± 1.83 (range, 0.08 to 7.70) minutes and a radiation dose of 1.31 ± 1.43 (range, 0.07 to 5.98) mGy were observed in the open modified Lapidus cohort. Fluoroscopy time between the cohorts did not differ markedly ( P = 0.123); however, the META group demonstrated a higher radiation dose than the open modified Lapidus group ( P = 0.007). The META procedure had a markedly higher radiation dose compared with the open modified Lapidus procedure, although both remain substantially below the International Commission on Radiological Protection recommended occupational exposure of less than 20.00 mSv per year. Despite the META procedure generating an average radiation dose of 2.02 mGy per case, surgeons receive only 0.50% of the dose; thus, nearly 1,980 procedures would be required to exceed the 20.00 mSv annual occupational limit. These findings suggest that concerns about radiation exposure should not necessarily deter providers from performing the META technique for bunion correction. III (Retrospective Comparative Study).

3:36 PM Abstract No. 65 Ureteral stent placement prior to percutaneous nephrostomy is associated with decreased radiation dose and fluoroscopy time

Category: Midfoot/Forefoot, Bunion DiabetesKeywords: Ankle, Degenerative, Hindfoot DeformityIntroduction/Purpose: Intraoperative fluoroscopy has become essential in orthopedic surgery, particularly with the rise of minimally invasive surgery (MIS) techniques. Despite the advantages of minimally invasive foot and ankle surgery, it raises concerns about radiation exposure to both patients and surgical staff. The purpose of this study was to evaluate fluoroscopy time and radiation dose (cumulative air kerma) associated with open versus MIS bunion correction, comparing the open modified Lapidus procedure and the minimally invasive distal first metatarsal transverse osteotomy and akin osteotomy (META). It was hypothesized that the META procedure would be associated with increased radiation dose and fluoroscopy time compared to the open modified Lapidus procedure.Methods: A retrospective review was conducted for patients who underwent bunion surgery between January 2021 and June 2025 by two fellowship-trained orthopedic foot and ankle surgeons at a single academic institution. A total of 294 patients met inclusion criteria. Of these, 258 patients underwent a META procedure and 36 underwent an open modified Lapidus procedure. Fluoroscopy time (minutes) and radiation dose (mGy) were compared between groups.Results: A mean fluoroscopy time of 2.13±1.27 (range, 0.06-7.05) minutes and a radiation dose of 2.02±1.30 (range, 0.05-7.52) mGy were observed in the META cohort. An average fluoroscopy time of 1.63±1.83 (range, 0.08-7.70) minutes and a radiation dose of 1.31±1.43 (range, 0.07-5.98) mGy were observed in the open modified Lapidus cohort. There was no significant difference in fluoroscopy time between cohorts (p=0.123), however the META group demonstrated a higher radiation dose than the open modified Lapidus group (p=0.007).Conclusion: The META procedure had a significantly higher radiation dose compared to the open modified Lapidus procedure, though both remain substantially below the International Commission on Radiological Protection (ICRP) recommended occupational exposure of less than 20.00 mSv per year. Despite the META procedure generating an average radiation dose of 2.02 mGy per case, surgeons receive only 0.50% of the dose, thus, nearly 1,980 procedures would be required to exceed the 20.00 mSv annual occupational limit. These findings suggest that concerns about radiation exposure should not necessarily deter providers from performing the META technique for bunion correction.

Introduction/Purpose Neurointerventional procedures involve exposure to ionizing radiation for patients and the care team. Mechanical thrombectomy (MT) techniques can affect radiation, with lower exposure when contact aspiration (CA) is used compared to combination stentriever‐assisted aspiration (SA) The Monopoint system consists of a Base Camp guide sheath, HiPoint 88 catheter‐extender, and Tenzing 8 delivery device. Monopoint system MT has been shown to have higher rates of first pass effect (FPE), less need for technical crossover, and fewer passes to achieve recanalization. We hypothesize that MT with Monopoint will be associated with shorter procedural temporal metrics and lower radiation exposure and dose. Materials/Methods IRB‐approved retrospective analysis was performed to identify MT cases across four high‐volume stroke centers for ICA terminus or M1 occlusion. Demographics, clinical presentation, angiography suite, procedure date, operator, LVO location, technique, and equipment utilized were noted. Patients were assigned to Monopoint, CA, or SA based on the first‐line technique employed. Patients requiring rescue/bailout stenting or cases with MT technique not clearly within one of the three above‐described cohorts were excluded. Times to first (TFP) and last pass (TLP) were all recorded. Fluoroscopy time, dose‐area product (DAP), and radiation dose were tabulated. Paired t‐tests were performed to compare procedural times and radiation data among treatment groups. Multivariable analysis was then performed, removing any independent variables with p&gt;0.20 in univariable tests to account for possible residual confounding. Results 151 patients met inclusion criteria—77 Monopoint, 32 CA, 42 SA. Crossover was less common in the Monopoint group (6.5%) compared to CA (34.4%) or SA (7.1%, p=0.001). TFP was shortest with Monopoint (13.3 min), compared to CA (20.5) and SA (20.4, p&lt;0.001). TLP was shortest with Monopoint (23.8 min) compared to CA (38.0) and SA (41.8, p&lt;0.001). There was no significant difference in fluoroscopy time between Monopoint (17.7 min) and CA (17.6, p=0.835); both were lower than SA (26.4, p&lt;0.001). DAP was lowest for Monopoint (18,854 µGy*m 2 ) compared to CA (31,325) and SA (29,483, p&lt;0.001). Radiation dose was lowest with Monopoint (884 mGy) compared to CA (1095) and SA (1994, p&lt;0.001). No associations were noted between any of these outcome variables and angiography suite, procedure date, operator, or LVO location. In multivariable analysis, all Monopoint associations persisted. TFP was inversely associated with Monopoint (p&lt;0.001). TLP was inversely associated with Monopoint use (p=0.002) and crossover (p=0.002), and it was associated with number of passes (p&lt;0.001). Fluoroscopy time was associated with number of passes (p&lt;0.001). DAP was inversely associated with Monopoint (β=‐15049, p=0.001) and associated with number of passes (β=4124, p=0.017). Similar associations persisted for radiation dose with Monopoint (β=‐883.9, p=0.004) and number of passes (β=440.9, p&lt;0.001). Conclusion MT for occlusions of the ICA terminus or M1 had shorter procedural times with Monopoint compared to CA and SA. Fluoroscopy times were comparable between Monopoint and CA. DAP and radiation dose were lowest with Monopoint compared to CA and SA. Further investigation is warranted to assess other clinical and technical factors that affect procedure duration, DAP, and radiation dose.

Objective: To study the cut-off values of urinary microalbumin (mAlb), transferrin (TRF) and α1-microglobulin (α1-MG) during pregnancy in pre-eclampsia (PE) with proteinuria. Methods: A total of 210 pregnant women were enrolled in Renji Hospital from January 2016 to December 2019, including 92 (43.8%) cases of PE pregnant women and 118 (56.2%) cases of normal pregnant women. According to the diagnostic test evaluation method, the positive predictive values, negative predictive values and accuracy of non-pregnant cut-off values of urinary mAlb, TRF and α1-MG for the quantitative determination of 24-hour proteinuria were analyzed. The receiver operating characteristic (ROC) curve was applied to determine the optimal cut-point values of urinary mAlb, TRF and α1-MG during pregnancy. Results: (1) The diagnostic study of non-pregnant adults urinary mAlb, TRF and α1-MG cut-off values for the determination of 24-hour proteinuria value: when urinary mAlb was 30.0 mg/L, TRF was 2.5 mg/L, α1-MG was 12.5 mg/L as the cut-off value, the positive predictive values of the corresponding 24-hour proteinuria value≥ 300 mg were 88.1% (89/101), 88.2% (90/102) and 78.9% (75/95), its negative predictive values were 97.2% (106/109), 98.1% (106/108) and 85.2% (98/115), its diagnostic accuracy were 92.9% (195/210), 93.3% (196/210) and 82.4% (173/210), respectively. As the 24-hour proteinuria value≥ 300 mg was the golden standard, there were significant differences between the diagnostic method of the non-pregnant cut-off value of urinary mAlb, TRF and the golden standard (P<0.05). There was no significant difference between the diagnostic method of the non-pregnant cut-off value of urinary α1-MG and the golden standard (P>0.05). (2) Research on the ROC curve and the optimal cut-point value of urinary mAlb, TRF and α1-MG value: as the 24-hour proteinuria value≥ 300 mg as the criterion, the ROC curve of urinary mAlb, TRF and α1-MG were 0.992, 0.984 and 0.907, respectively. The optimal cut-point values of urinary mAlb, TRF and α1-MG were 86.5 mg/L (Youden index=0.927), 5.5 mg/L (Youden index=0.923), and 15.4 mg/L (Youden index=0.687). (3) The diagnostic study of the optimal cut-point value of urinary mAlb, TRF and α1-MG for the determination of 24-hour proteinuria value: according to the ROC results, when urinary mAlb was 86.5 mg/L, urinary TRF was 5.5 mg/L, and urinary α1-MG was 15.4 mg/L as the cut-off value, the positive predictive values of the corresponding 24-hour proteinuria value≥300 mg were 98.9% (86/87), 95.7% (88/92), 87.7% (71/81), and its negative predictive values were 95.1% (117/123), 96.6% (114/118), 83.7% (108/129), and its accuracy were 96.7% (203/210), 96.2% (202/210), 85.2% (179/210). As the 24-hour proteinuria value≥ 300 mg was the golden standard, there was no significant difference between the diagnostic method of the best cut-off values of urinary mAlb, TRF, α1-MG and the golden standard (P>0.05). Conclusion: It is recommended to define the cut-off values of mAlb, TRF and α1-MG as 86.5 mg/L, 5.5 mg/L and 15.4 mg/L, respectively, during pregnancy.

In this study, we determined whether there were significant differences in procedure time, radiation dose, fluoroscopy time, and total contrast media dose when unruptured wideneck bifurcation aneurysms (WNBAs) were treated with the Woven EndoBridge (WEB) device and stent-assisted coil (SAC) embolization. The WEB device and SAC embolization (14:17) were used to treat 31 cases of internal carotid artery bifurcation, anterior communicating artery, middle cerebral artery bifurcation, and basilar bifurcation aneurysms between August 2021 and December 2022. The procedure time, radiation dose, fluoroscopy time, and total contrast medium dose between the 2 treatment groups were compared and analyzed. In the WEB device group, the results between operators were compared, and the follow-up radiologic outcomes were investigated. The procedure and fluoroscopy times were significantly shorter in the WEB device group. Radiation and total contrast media dose were also significantly smaller in the WEB device, but there was no significant difference in results between operators. The follow-up radiological outcome showed adequate occlusion in 83.3% (10/12) of cases. The WEB device can be used as an alternative treatment method among the available endovascular treatment methods for WNBAs to reduce radiation exposure and the dose of contrast media when used adequately with appropriate indications.

Low-dose interventional x-ray systems have been shown to substantially reduce radiation dose in the pediatric and adult structural and interventional realm. We evaluated our single-center experience with Philips AlluraClarity software for all cardiovascular procedures; we also compared performance relative to patient body size. A total of 1155 patients were included. Data on dose area product (DAP) for radiation exposure, along with body surface area (BSA) and fluoroscopy time, were retrospectively collected for 467 patients before implementation of the Clarity system and for 688 patients after system implementation. DAP was then compared to BSA and fluoroscopy time. BSA was categorized into four quartiles to assess the relationship between radiation dose across small to large patient size populations. The mean BSA between two groups was similar (2.03 vs 2.02 m2, P = 0.48), with a 44.7% reduction in radiation dose with DAP indexed to BSA. A significant reduction in radiation dose was seen across all quartiles, with the highest reduction in the post-Clarity sample population with the largest BSA. Fluoroscopy time in the pre-Clarity period was lower than in the post-Clarity period (mean of 7.6 vs 10.2 min; P ≤ 0.001), with a total 57.7% radiation dose reduction with DAP indexed to fluoroscopy time (P ≤ 0.001). There was a 45.2% overall decrease in radiation dose with AlluraClarity (P ≤ 0.001). In conclusion, AlluraClarity significantly reduced overall radiation dose, irrespective of BSA. The largest reduction in radiation was seen in patients with the highest BSA, suggesting that obese patients derive the most benefit. To our knowledge, this is the first study to describe this relationship with BSA and AlluraClarity. The Clarity system also substantially reduced radiation dose despite longer fluoroscopy time.

Effect of Real-Time Radiation Dose Feedback on Pediatric Interventional Radiology Staff Radiation Exposure

To determine whether suprapatellar nailing (SPN) over time can decrease operative time and radiation exposure when compared with infrapatellar nailing (IPN) of tibial shaft fractures. Retrospective. Single, Level 1 trauma center. Extra-articular adult tibial shaft fractures treated with intramedullary nailing alone within a 7-year period. Patients were treated with SPN or IPN techniques based on the discretion of the operating surgeon. Operative time and radiation exposure. Three hundred forty-one fractures (SPN: 177, IPN: 164) were included in the analysis. No differences in patient body mass index, sex, or open fracture incidence existed between the 2 groups. A significant difference in average operative time (IPN 130 minutes vs. SPN 110 minutes, P < 0.01), fluoroscopy time (IPN 159 minutes vs. SPN 143 minutes, P = 0.02), and radiation dose (IPN 8.6 mGy vs. SPN 6.5 mGy, P < 0.01) existed between IPN and SPN. Early tibias treated with SPN had similar operative times (P = 0.11), fluoroscopy time (P = 0.94), and radiation dose (P = 0.34) compared with IPN. Later SPN patients had significantly lower operative time (P = 0.03), fluoroscopy time (P < 0.01), and radiation dose (P < 0.013) compared with earlier SPN. Regression analysis revealed with the increased use of SPN, operative time, fluoroscopy time, and radiation dose significantly decreased (P = 0.018, 0.046, 0.011). Tibia fractures treated with SPN have significantly decreased operative times and radiation exposure compared with those treated with IPN, after allowing time for the surgeon to gain sufficient experience with the technique. The surgeon should consider this when deciding to adopt this technique. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.