Cumulative Fluoroscopy Time Research Articles

Factors affecting radiation dose, radiation exposure time and procedural time in arterial embolization for active hemorrhage.

To evaluate patient and procedure-related factors contributing to the radiation dose, cumulative fluoroscopy time (CFT), and procedural time (PT) of Arterial Embolization (AE) for suspected active bleeding. Data on patients who underwent AE for suspected bleeding was retrospectively gathered between January 2019 and April 2022. Data collected included the dependent variables consisting of dose-area product (DAP), CFT, PT, and independent variables consisting of demographic, bleeding-specific, and procedure-specific parameters. All statistical computations were performed in SPSS statistics. The alpha value was set at 0.05. Data from a total of 148 AE were collected with an average patient's age of 61.06 ± 21.57 years. Higher DAP was independently associated with male sex (p < 0.002), age ranges between 46 and 65 years (p = 0.019) and > 66 years (p = 0.027), BMI above 30 (p = 0.016), attending with less than 10 years of experience (p = 0.01), and bleeding in the abdomen and pelvis (p = 0.027). Longer CFT was independently associated with attending with less than 10 years of experience (p < 0.001), having 2 (p = 0.004) or > 3 (p = 0.005) foci of bleed, and age between 46 and 65 years (p = 0.007) and ≥ 66 years (p = 0.017). Longer PT was independently associated with attending with less than 10 years of experience (p < 0.001) and having 2 (p = 0.014) or > 3 (p = 0.005) foci of bleed. The interventionist experience influenced radiation dose, CFT and PT. Dose was also affected by patients' sex, age, BMI, as well as bleeding location. CFT was also affected by patients' age, and both CFT and PT were also affected by the number of bleeding foci. These findings highlight the multifaceted factors that affect radiation dose and procedural time, emphasizing the importance of interventionist expertise, patient's age, sex, BMI, location and number of bleeds.

Ultrasound-guided Jamshidi needle puncture to reduce radiation exposure during percutaneous pedicle screw placement: study protocol for a randomised controlled trial

IntroductionPercutaneous pedicle screw placement (PPSP) is a minimally invasive procedure highly dependent on fluoroscopic guidance, which results in increased radiation exposure and prolonged operative time. Ultrasound can image the lumbar...

Short-term effectiveness of lateral raft plate combined with Jail screw fixation in treatment of tibial plateau collapse fractures involved posterior-lateral column

To investigate the short-term effectiveness of proximal tibial lateral raft plate combined combined with or without Jail screw fixation in the treatment of tibial plateau collapse fractures involved posterior-lateral column. A retrospective analysis was performed on 106 patients (106 knees) with tibial plateau collapse fracture involved posterior-lateral column admitted between January 2016 and January 2021. According to the combination with Jail screw fixation or not, patients were divided into control group (treated by lateral raft plate without Jail screw fixation, 52 cases) and study group (treated by lateral raft plate with Jail screw fixation, 54 cases). There was no significant difference between the two groups in terms of gender, age, affected knee side, cause of injury, Schatzker classification, Tscherne-Gotzen classification, time from injury to operation, and preoperative lateral tibial plateau posterior slope angle (PSA), tibial plateau varus angle (TPVA), Rasmussen anatomical score (P>0.05). The operation time, cumulative fluoroscopy time, intraoperative blood loss, hospitalization stay, fracture healing time, complications, and lateral tibial plateau PSA, TPVA, Rasmussen anatomical score detected by X-ray films and CT before operation and at 1 year after operation of the two groups were recorded and compared. The number of cases of articular surface collapse in the two groups was recorded at 1 year after operation, and the effectiveness was evaluated by American Special Surgery Hospital (HSS) score. All patients were followed up 12-32 months (mean, 19.5 months). There was no significant difference between the two groups in operation time, cumulative fluoroscopy time, intraoperative blood loss, hospitalization stay, and fracture healing time (P>0.05). There were 2 patients (3.7%) in the study group and 3 patients (5.8%) in the control group with superficial wound infection, which were cured after debridement and dressing change. There was no significant difference in the incidence between the two groups (χ2=0.252, P=0.616). There was no complication such as vascular and nerve injury, internal fixation failure, nonunion or malunion of fracture, and deep vein thrombosis of lower limbs in both groups. At 1 year after operation, 9 cases (17.3%) in the control group had joint collapse of 2-3 mm, while only 2 cases (3.7%) in the study group had joint collapse, showing significant difference (χ2=5.271, P=0.022). At 1 year after operation, the PSA, TPVA, and Rasmussen anatomical scores of the two groups were significantly improved when compared with preoperative ones (P<0.05); the differences of pre- and post-operative PSA, TPVA, Rasmussen anatomical score, and postoperative HSS score in the study group were significantly better than those in the control group (P<0.05). The lateral raft plate combined with or without Jail screw fixation can achieve satisfactory short-term effectiveness in the treatment of tibial plateau collapse fractures involved posterior-lateral column. Combined with Jail screw, it can enhance the fixation and avoid the occurrence of secondary articular surface collapse, which can be used as a better choice.

Rehearsals using patient-specific 3D-printed aneurysm models for simulation of endovascular embolization of complex intracranial aneurysms: 3D SIM study

BackgroundIn neurovascular treatment planning, endovascular devices to manage complex intracranial aneurysms requiring intervention are often selected based on conventional measurements and interventional neuroradiologist experience. A recently developed technology allows a patient-specific 3D-printed model to mimic the navigation experience. The goal of this study was to assess the effect of pre-procedure 3D simulation on procedural and clinical outcomes for wide-neck aneurysm embolization. Materials & methodsIn this unblinded, non-randomized, prospective, multicenter study conducted from November 18 through December 20, patients with complex intracranial aneurysms (neck > 4 mm or ratio < 21) were treated by WEB or flow diverter stents (FDS). The primary endpoint was concordance between simulation and procedure, 3D-printed model accuracy as well as embolization outcomes including complications, procedure times, and radiation dose were also assessed. Secondary endpoint was to compare versus a retrospective WEB cohort. ResultsTwenty-one patients were treated, 76% of cases by WEB and 24% by FDS. Concordance between post-simulation and real procedure efficiency was 0.85 [0.69 – 1.00] for size device selection and 0.93 [0.79 – 1.00] for wall-apposition/aneurysm neck closure. Geometrical accuracy of the 3D-printed model showed a mean absolute shift of 0.11 mm. Two complications without major clinical impact were reported with a post-operative mRS similar to pre-procedure mRS for all patients. ConclusionsRehearsal using accurate 3D-printed patient-specific aneurysm models enabled optimization of embolization strategy, resulting in reduced procedure duration and cumulative fluoroscopy time which translated to reduced radiation exposure compared to procedures performed without simulation.

The use of ureteral access sheath during mini-percutaneous nephrolithotomy with high-power holmium YAG laser.

To present our preliminary results and describe a technical modification of mini-PCNL (12Fr) with the insertion of a ureteral access sheath (UAS) to facilitate the procedure. A prospective study for the time period of January 2020 to January 2021 was conducted including patients with renal stones sized ≤ 25mm in whom prone mini-PCNL (tract size 12Fr) together with the retrograde insertion of UAS was performed. All patients had been prestented at least 1week prior to the planned surgery. A single-step tract dilation to 12Fr diameter was performed through a nonpapillary medial puncture. The lithotripsy was achieved using high-power holmium yttrium aluminum garnet laser (Ho:YAG) with the 60W power setting (40Hz and 1.5J). The follow-up investigations were planned at 1-month after the surgery. In total, 32 patients with the median age and stone size of 56.5 (IQR = 53-62) years and 20.8 (IQR = 19.3-22.7) mm were included. The median operative and cumulative fluoroscopy time were 34.0 (IQR = 29.9-37.5) and 1.9 (1.8-2.1) min, respectively. The stone-free rate (SFR) at 1-month follow-up was 93.8% (30/32). Only one patient developed a fever and required prolonged antibiotic administration. None of the patients experienced clinically significant bleeding. Our preliminary results showed that the use of UASs during mini-PCNL procedures is feasible and provides directed evacuation of the stone fragments reaching 93.8% SFR at a 1-month follow-up. Future well-designed studies are necessary to prove our findings.

Digital Subtraction Myelography is Associated with Less Radiation Dose than CT-based Techniques

Both CT myelogram (CTM) and digital-subtraction myelogram (DSM) can be used to evaluate patients for possible cerebrospinal fluid (CSF) leaks. DSM is a relatively new technique. No data exists on the radiation dose associated with this procedure, and how it compares with CTM. All patients who underwent DSM for spontaneous intracranial hypotension (SIH) refractory to blood patching from Dec 2016 - Sept 2019 were retrospectively assessed. DSM dose factors were then recorded (cumulative fluoroscopy time, total kerma area product (KAP, mGy.cm2), cumulative air kerma (mGy), as well as CTM dose factors (included CTDIvol (mGy) and dose-length product (DLP, mGy.cm). These indices were then used to calculate the effective dose for both procedures using standardized conversion factors. 61 DSMs were performed in 42 patients, 33 of which also underwent CTM. The median effective dose was 6.6 mSv per DSM study (range: 1.2 - 17.7). On a per-patient basis (i.e. those patients who underwent more than one DSM (as the initial one was negative), the median total effective dose was 13 mSv for their total DSM imaging (range: 2.6 -31.7). For the CTM, the median effective dose was 19.7 mSv (range: 3.2 - 82.4 mSv). The radiation dose with DSM appears to be significantly lower than that of CTM (p = 0.0005), when looking at CTM doses both from our institution and in the published literature.

Patient radiation exposure for endovascular deep venous interventions

ObjectiveThe study aimed to assess the cumulative radiation exposure from preoperative, periprocedural, and follow-up imaging to patients who underwent common endovascular deep venous interventions for acute and chronic central venous outflow obstructive diseases; namely, deep vein thrombosis (DVT) thrombolysis, unilateral chronic iliofemoral venous stenting, and inferior vena cava (IVC) reconstruction in a single center. MethodsPatients who had DVT thrombolysis of upper extremity (UE) DVT and lower extremity (LE) DVT, unilateral chronic iliofemoral venous stenting, and endovascular IVC reconstruction between May 1, 2012, and July 31, 2017, in a single unit were retrospectively reviewed. Demographic data, anatomic DVT, imaging, technical details of the index procedure, follow-up, and radiation exposure measured in dose-length product, dose-area product (DAP), and fluoroscopy time (FT) from related computed tomography scans and interventions were analyzed. Mann-Whitney U tests were performed to assess for significance of differences between subgroups. A P value of less than .05 was considered significant. ResultsIn total, 20 UE DVT thrombolysis, 91 LE DVT thrombolysis, 56 unilateral chronic iliofemoral venous stenting, and 39 endovascular IVC reconstruction patients were included in the study, with the following median ages: 39 years (range, 20-67 years), 44 years (range, 15-78 years), 45 years (range, 20-80 years), and 35 years (range, 18 -73 years), respectively. The median cumulative DAP for the index DVT thrombolysis was 9.2 Gycm2 (range, 0.2-176.0 Gycm2) for LE DVT and 2.0 Gycm2 (range, 0.1-11.7 Gycm2) for UE DVT (P < .0001). The median cumulative FT for the index thrombolysis was 981 seconds (range, 20-4890 seconds) and 837 seconds (range, 19-2895 seconds) for LE DVT and UE DVT, respectively (P = .18). For unilateral chronic iliofemoral venous stenting, the median cumulative DAP and FT were 32.4 Gycm2 (range, 0.1-289.6 Gycm2) and 660 seconds (range, 246-4200 seconds), respectively. Meanwhile, the median cumulative DAP and FT for the endovascular IVC reconstruction were 60.8 Gycm2 (range, 2.5-269.1 Gycm2) and 2846 seconds (range, 836-11682 seconds), respectively. The median DAP for secondary procedures during follow-up was 6.6 Gycm2 (range, 0.8 186.5 Gycm2), 1.9 Gycm2 (range, 0.2-111.7 Gycm2), and 24.3 Gycm2 (range, 0.2-157.5 Gycm2) for LE DVT thrombolysis, unilateral chronic iliofemoral venous stenting, and endovascular IVC reconstruction, respectively. ConclusionsPatient radiation exposure for endovascular deep venous interventions for central venous outflow obstruction measured in DAP and FT seemed to be less than and at most similar to anatomically comparable arterial interventions in the literature. However, these patients were usually much younger than those with arterial diseases and may need secondary interventions involving further radiation exposure in their lifetime.

Radiation Exposure to Patients With Acute Deep Venous Thrombosis Treated With Thrombolysis

Catheter thrombolysis of acute deep venous thrombosis (DVT) of the upper extremity (UE) and lower extremity (LE) is being increasingly carried out following emerging evidence to support that it reduces the risk for development of post-thrombotic syndrome. Such intervention and its potential secondary procedures may expose the patients to significant cumulative radiation over time. Furthermore, these patients are often relatively younger than those with arterial diseases. The study aimed to assess the cumulative radiation exposure to patients who had thrombolysis for acute DVT of the LE and UE. Patients who had catheter-directed thrombolysis or pharmacomechanical catheter thrombolysis for acute DVT involving the LE and UE in a single unit between May 1, 2012, and April 30, 2016, were identified retrospectively. Demographic data, anatomic DVT, imaging, technical details of the index thrombolysis, follow-up, and estimated radiation exposure measured in dose-area product (DAP) and fluoroscopy time (FT) from related interventions were collected and analyzed. DAP refers to the radiation absorbed by irradiated tissue multiplied by the area irradiated, which gives a rough estimation of the risk of stochastic effects. Mann-Whitney test was performed to assess for statistical differences between subgroups, and P < .05 was considered significant. There were 91 patients (39 men) with LE DVT and 20 patients (12 men) with UE DVT identified. The mean (range) ages of patients undergoing thrombolysis in the LE DVT and UE DVT groups were 43.5 (15-78) years and 39.1 (20-67) years, respectively. The median (range) cumulative DAP for the index thrombolysis was 9238 (204-175,983) mGy∙cm2 for LE DVT and 1982 (115-11,736) mGy∙cm2 for UE DVT (P < .0001). The median cumulative FT for the index thrombolysis was 981 (20-4890) seconds and 837 (19-2895) seconds for LE DVT and UE DVT, respectively (P = .18). The mean follow-up for LE and UE DVT was 16.4 (1-50) months and 4.3 (1-19) months, respectively. During the follow-up, 36 (40%) patients with LE DVT had secondary procedures involving the use of fluoroscopy including venography, thrombolysis, venoplasty, and stent extension. The median (range) cumulative DAP and FT for the secondary procedures in the LE DVT group were 6564 (800-186,495; n = 35) mGy∙cm2 and 876 (96-12,910; n = 32) seconds, respectively. Patients with acute DVT who had thrombolysis appeared to be exposed to radiation that was comparable to that with simple LE arterial angioplasty but much less than with endovascular aortic aneurysm repair reported in the literature. However, these patients were usually much younger than those with arterial diseases and may need secondary interventions involving further radiation exposure in their lifetime. Therefore, further studies should investigate the long-term side effects of radiation exposure in these patients and ways of reducing it, including the use of intravascular ultrasound and magnetic resonance imaging technology.

Factors influencing radiation exposure during internal fixation of hip fractures

The use of fluoroscopy is of great importance for operative fixation of fractures. Previous studies have shown an increased fluoroscopy time for intramedullary nails and with junior surgeons in comparison with more experienced surgeons. We examined the impact of operation length on fluoroscopy dose, cumulative fluoroscopy time between consultant and registrar surgeons and cumulative fluoroscopy time between dynamic hip screw and intramedullary nailing. We performed a retrospective cohort study of all patients admitted to our centre over the period of 1year. Patients who underwent dynamic hip screw (DHS) or intramedullary (IM) nailing were identified from our in-hospital hip fracture database. Intraoperative fluoroscopy images were then accessed through our hospital's medical imaging software. A total of 137 patients were identified. Fluoroscopy reports were not available for 49 patients, resulting in a final total of 88 patients. Patients whose operation lasted longer than 1h received a statistically significant higher dose of radiation (183.83 cGYM2 vs. 368.22 cGYM2; p value 0.0002). Operations performed by a consultant resulted in less cumulative fluoroscopy time in comparison with those performed by a registrar or specialist registrar although this was not statistically significant (00:00:53 vs. 00:00:45; p vaue 0.38). Cumulative fluoroscopy time was less in dynamic hip screw compared to long intramedullary nails (00:00:39 vs. 00:01:29; p value <0.001) and short intramedullary nails (00:00:39 vs. 00:01:52; p value 0.387). Studies, which had a cumulative fluoroscopy time exceeding 50 secs, delivered a higher radiation dose (434.34cGYM2 vs. 150.51cGYM2; p value <0.001). We concluded that there is no significant impact in cumulative fluoroscopy time in operations performed by either a registrar or consultant. Dynamic hip screws have a lower fluoroscopy time in comparison with long intramedullary nails.

Effects of staged versus ad hoc percutaneous coronary interventions on renal function-Is there a benefit to staging?

The purpose of this study is to determine whether ad hoc (same session) percutaneous coronary intervention, and staged (multiple session) percutaneous coronary intervention (PCI) have different renal outcomes. This is a retrospective cohort study that compares the maximal decline in glomerular filtration rate (GFR) at various times points (3-6days, 1-4weeks, 4-12weeks) after either ad hoc or staged PCI. 115 patients undergoing staged PCI and 115 matched ad hoc PCI controls were included in the study. They were equivalent in baseline GFR, left ventricular ejection fraction and intra-procedural volume status based on LVEDP. The group undergoing staged PCI had greater cumulative fluoroscopy time, SYNTAX score and number of stents placed. Staged PCIs used less contrast per catheterization (155.0±5.6mL) but higher cumulative contrast dose (326.6±14.0mL) compared to ad hoc PCIs (193.4±7.2mL). Following intervention, there was a progressive decline in renal function that did not significantly differ between the ad hoc and staged groups. In the subgroup of patients with initial GFR ≤60cm3/min, staged PCI was associated with 2.6-fold greater decline in renal function 4-12weeks after the procedure compared to ad hoc. A propensity match analysis performed in patients with GFR ≤60cm3/min confirmed worse renal function in the staged group at 4-12weeks. Staged PCI exposes patients to greater cumulative contrast agent loads. The decline in renal function observed in both groups did not differ significantly, however worse renal outcomes were observed in the staged PCI group with baseline GFR ≤60cm3/min.

Cumulative Effective and Individual Organ Dose Levels in Paediatric Patients Undergoing Multiple Catheterisations for Congenital Heart Disease.

This study examines the cumulative radiation dose levels received by a group of children who underwent multiple cardiac catheterisation procedures during the investigation and management of congenital heart disease (CHD). The purpose is to calculate cumulative doses, identify higher dose individuals, outline the inconsistencies with risk assessment and encourage the establishment of dose databases in order to facilitate the longitudinal research necessary to better understand health risks. A retrospective review of patient records for 117 paediatric patients who have undergone two or more cardiac catheterisations for the investigation of CHD was undertaken. This cohort consisted of patients who were catheterised over a period from September 2002 to August 2014. The age distribution was from newborn to 17 y. Archived kerma-area product (PKA) and fluoroscopy time (T) readings were retrieved and analysed. Cumulative effective and individual organ doses were determined. The cumulative PKA levels ranged from 1.8 to 651.2 Gycm2, whilst cumulative effective dose levels varied from 2 to 259 mSv. The cumulative fluoroscopy time was shown to vary from 8.1 to 193.5 min. Median cumulative organ doses ranged from 3 to 94 mGy. Cumulative effective dose levels are highly variable but may exceed 250 mSv. Individual organ and effective dose measurements remain useful for comparison purposes between institutions although current methodologies used for determining lifetime risks are inadequate.

Catheter Ablation of Ischemic Ventricular Tachycardia With Remote Magnetic Navigation: STOP-VT Multicenter Trial.

Catheter ablation is an effective treatment of scar-related ventricular tachycardia (VT), but the overall complexity of the procedure has precluded its widespread use. Remote magnetic navigation (RMN) has been shown to facilitate cardiac mapping and ablation of VT in a retrospective series. STOP-VT is the first multicenter, prospective, single-arm and single-procedure study evaluating RMN-based mapping and ablation of post-infarction VT. Patients with documented VT and prior MI, in whom an ICD was implanted either for primary or secondary prevention, were recruited from four EU and US centers. Either a transseptal (48 patients) or transaortic (5 patients) approach was employed to gain access for ventricular endocardial mapping/ablation during VT (entrainment mapping, activation mapping) and/or substrate mapping in sinus rhythm (elimination of fractionated/late potentials, variable extent of substrate modification) with RMN and irrigated RF ablation. The primary endpoints were as follows: (i) non-inducibility of the target VT or any other sustained VT; (ii) elimination of sustained VT/VF during ICD follow-up of up to 12 months. The cohort included 53 consecutive patients (median age 67 years, 49 men, median LVEF 31%). One hemodynamically unstable patient was excluded at the onset of mapping. Inducibility of sustained VT was achieved an average of 2.2 times per patient (1-8), with mean tachycardia cycle length (TCL) 374 milliseconds (179-510). Mean total procedure and fluoroscopy times were 223 minutes and 8.7 minutes, respectively; mean cumulative fluoroscopy time during mapping and ablation was 0.95 minutes; maximum power averaged 42.3 W with nominal saline 30 cc/min irrigation; mean cumulative RF time was 38 minutes. Non-inducibility of the target VT was achieved in 49/52 patients (94.2%) and non-inducibility of any VT was achieved in 38/52 patients (73.1%). A combination of RMN and manual ablation was performed in two patients, rendering one non-inducible. During the 12-month ICD follow-up period, freedom from any sustained VT/VF was observed in 30 patients (62%), of which 19 (63%) were off antiarrhythmic medications. Five patients expired during follow-up: one presented with a VT storm, but for the others, death was not related to VT/VF (MI-cardiogenic shock, pulmonary embolism, bronchogenic carcinoma, end stage heart failure). No procedural complications were reported. This first prospective, single-procedure, multicenter study indicates that remote magnetic navigation is a safe and effective method for catheter ablation of post-infarction VT.

Safety, Minimization, and Awareness Radiation Training Reduces Fluoroscopy Time During Unilateral Ureteroscopy

To determine the impact of Safety, Minimization and Awareness Radiation Training (SMART) on fluoroscopy time during unilateral uncomplicated ureteroscopy for urolithiasis performed by urology residents. All consecutive ureteroscopy cases for urolithiasis meeting inclusion criteria and performed by first-year urology residents over a 2-year period were reviewed. Fluoroscopy times during SMART and without SMART were compared. A total of 202 ureteroscopy cases were reviewed. The mean patient age was 48.7 years. The mean stone diameter was 7.6 ± 3.3 mm. The mean operating time was 79.8 ± 34.3 minutes. The mean cumulative fluoroscopy time was 85.6 ± 36.9 seconds per case. A Spearman rank correlation identified 8 variables significantly correlated with fluoroscopy time, with the most significant correlation between shorter fluoroscopy time and SMART exposure (rho = 0.532; P <.001). Multivariate regression analysis (r = 0.701) revealed that fluoroscopy time was significantly shorter with SMART (P <.001). Post hoc comparisons revealed the fluoroscopy time of the cases performed during SMART (mean, 45 seconds) to be significantly shorter than the fluoroscopy time of cases performed by the same residents before SMART (mean, 102 seconds; P = .005), and the fluoroscopy time of cases performed by residents the previous year with similar ureteroscopic experience but without SMART (mean, 78 seconds; P <.001). SMART reduces fluoroscopy time during unilateral uncomplicated ureteroscopy for urolithiasis performed by urology residents by 56%.

Epicardial mapping and ablation of arrhythmias: is magnetic navigation the answer we have been waiting for?

Epicardial mapping and ablation of arrhythmias: is magnetic navigation the answer we have been waiting for?

Effect of Fluoroscopy Utilization Monitoring on Fluoroscopy Times During ERCP

Purpose: Prolonged use of fluoroscopy is associated with medical hazards for patients and the medical staff. Recent recommendations were made of using fluoroscopy time (FT) as a quality measure. Hence, there is an increased emphasis on efficient use of fluoroscopy. We hypothesize that informing the endoscopists of their fluoroscopy times and that their utilization of fluoroscopy is being tracked would result in a reduction of their overall fluoroscopy utilization as measured by FT. Methods: We reviewed the medical charts of patients who underwent ERCP in our center from April 2011 to April 2012. On December 15, 2011, the endoscopists were informed about their mean FT during ERCP, were encouraged to decrease their use for fluoroscopy and were informed their FT would be monitored. After collecting the data, we compared the mean FT of the endoscopists individually and as a group before and after December 15, 2011, using Student's t-test and ANOVA single factor. Results: A total of 293 patients and 3 endoscopists were included in the study. During the entire study period, the mean FT among the endoscopists as a group was 8.12 minutes. The means of FT for each endoscopist were 4.61, 9.92, and 9.21 minutes, respectively (P<0.0001). Prior to informing the endoscopists that their FT was being tracked, utilization of fluoroscopy was significantly variable among endoscopists with the mean FT for all endoscopists 9.04 minutes and the mean FT for each endoscopist being 6.06, 11.43, and 7.67 minutes, respectively (p<0.02). After informing the endoscopists that their FT will be followed, there was a trend toward a decrease in FT among the group (9.04 vs. 7.4 minutes). Nonetheless the decrease in FT did not reach statistical significance (p=0.06). After informing the endoscopists that their FT will be followed, the changes in FT among endoscopists were variable. The first endoscopist's FT significantly decreased (6.06 to 3.93 min, p<0.02). The second endoscopist's FT decreased but did not reach statistical significance (11.43 to 8.8 min, p=0.14). The third endoscopist's FT increased but did not reach statistical significance (7.67 to 11.47 minutes, p=0.06). We found that the cumulative FT for all procedures since informing the endoscopists that their FT was being tracked was decreased by 273.9 minutes. Based on this, we estimate that the cumulative FT during ERCP in our institution will decrease by 694.2 minutes during 2012 (11.6 hrs). Conclusion: Fluoroscopic utilization measured by FT during ERCP is variable among endoscopists. Endoscopists' recognition that their fluoroscopy utilization during ERCP is being tracked leads to variable results among endoscopists. Nonetheless, overall it leads to a trend in reducing fluoroscopy utilization.Table: [201] Fluoroscopy utilization

Screw Placement for Acetabular Fractures

Screw navigation techniques with different image guidance [2-dimensional (2D) vs. 3-dimensional (3D) fluoroscopy] were evaluated for acetabular fracture surgery. Two-dimensional and 3D navigation images were analyzed for visualization of different osseous corridors: supra-acetabular, anterior column, posterior column, and infra-acetabular. Forty guide wires per group were placed in synthetic pelvis with a prefabricated soft tissue envelope (10 per group) using a 2D or 3D fluoroscopic navigation procedure. Duration of the single steps for each procedure and of cumulative fluoroscopy time was measured. The accuracy of guide wire placement was evaluated visually and in 3D cone-beam scans. The overall procedure time per pelvis was significantly reduced in the 3D group compared with the 2D group [mean ± standard error (SE) (minutes): 50.11 ± 1.38 vs. 63.42 ± 2.32; P < 0.0001]. A trend to reduction in image acquisition time [mean ± SE (minutes): 12.37 ± 1.34 vs. 15.43 ± 1.03; P = not significant] and significant increase in the cumulative fluoroscopy time [mean ± SE (seconds): 64 ± 9 vs. 13 ± 1.3; P < 0.0001) was measured in the 3D compared with the 2D group, caused by the 3D scan. Intra-articular misplacements were not observed in both the groups, but an increased accuracy could be achieved using the 3D image-based navigation procedure (perfect placement: 37 vs. 29; secure placement: 2 vs. 7; misplacement: 1 vs. 4). Both navigation procedures securely prevent an intra-articular penetration during drilling, but the 3D image-based navigation procedure increases the overall accuracy compared with the 2D image-based navigation technique (misplacement rates of 2.5% vs. 10%). Especially, in very narrow corridors (as the infra-acetabular screw path), the use of 3D navigation should be preferred.

Ionizing radiation absorption of vascular surgeons during endovascular procedures

Endovascular procedures have become an integral part of a vascular surgeon's practice. The exposure of surgeons to ionizing radiation and other safety issues have not been well studied. We investigated the radiation exposure of a team of vascular surgeons in an active endovascular unit and compared yearly dosages absorbed by various body parts among different surgeons. Patients' radiation exposure was also assessed. The radiation absorption of a team of vascular surgeons was prospectively monitored in a 12-month period. During each endovascular procedure, the effective body, eye, and hand radiation doses of all participating surgeons were measured by mini-thermoluminescent dosimeters (TLD) attached at the chest level under a lead apron, at the forehead at eye level, and at the hand. The type of procedure, fluoroscopy machine, fluoroscopy time, and personal and operating theatre radiation protection devices used in each procedure were also recorded. One TLD was attached to the patient's body near the operative site to measure the patient's dose. The yearly effective body, eye, and hand dose were compared with the safety limits of radiation for occupational exposure recommended by the International Commission on Radiation Protection (ICRP). The radiation absorption of various body parts per minute of fluoroscopy was compared among different surgeons. A total of 149 consecutive endovascular procedures were performed, including 30 endovascular aortic repairs (EVAR), 58 arteriograms with and without embolization (AGM), and 61 percutaneous transluminal angioplasty and stent (PTA/S) procedures. The cumulative fluoroscopy time was 1132 minutes. The median yearly effective body, eye, and hand dose for the surgeons were 0.20 mSv (range, 0.13 to 0.27 mSv), 0.19 mSv (range, 0.10 to 0.33 mSv) and 0.99 mSv (0.29 to 1.84 mSv) respectively, which were well below the safety limits of the ICRP. The mean body, eye, and hand dose of the chief surgeon per procedure were highest for EVAR. A significant discrepancy was observed for the average hand dose per minute of fluoroscopy among different surgeons. The mean radiation absorption of patients who underwent EVAR, AGM, and PTA/S was 12.7 mSv, 13.6 mSv, and 3.4 mSv, respectively. With current radiation protection practice, the radiation absorbed by vascular surgeons with a high endovascular workload did not exceed the safety limits recommended by ICRP. Variations in practice, however, can result in significant discrepancy of radiation absorption between surgeons.