International Multicenter Study Research Articles

Improved technical outcomes with converting thrombectomy techniques after failed first pass recanalization

BackgroundA higher number of recanalization attempts reduces the efficacy of endovascular thrombectomy (EVT) for acute ischemic stroke secondary to large vessel occlusion (LVO). We assessed the impact of switching EVT...

Anthropometric prediction models of body composition in 3 to 24month old infants: a multicenter international study

Anthropometric prediction models of body composition in 3 to 24month old infants: a multicenter international study

Nociception Coma Scale—Revised with Personalized Painful Stimulus Versus Standard Stimulation in Persons with Disorders of Consciousness: An International Multicenter Study

Nociception Coma Scale—Revised with Personalized Painful Stimulus Versus Standard Stimulation in Persons with Disorders of Consciousness: An International Multicenter Study

Total versus Partial Pancreatectomy in Patients with Pancreatic Cancer Arising from Multifocal or Diffuse Intraductal Papillary Mucinous Neoplasia - A Multicenter Observational Study.

To investigate the impact of total pancreatectomy (TP) on oncological outcomes for patients at high-risk of local recurrence or secondary progression in the remnant gland after partial pancreatectomy (PP) for IPMN-associated cancer. Major risk factors for invasive progression in the remnant gland include multifocality, diffuse main duct dilation, and the presence of invasive cancer. In these high-risk patients, a TP may be oncologically beneficial. However, current guidelines discourage TP, especially in elderly patients. This international multicenter study compares TP versus PP in patients with adenocarcinoma arising from multifocal or diffuse IPMN (2002-2022). Log-rank test and multivariable Cox-analysis with interaction analysis was performed to assess overall survival (OS), disease-free survival (DFS), and local-DFS. Of 359 included patients, 162 (45%) were treated with TP, whereas 197 (55%) underwent PP. Despite TP and PP having similar R0-rates (59% vs. 58%, P=0.866), patients undergoing a TP had significantly longer local-DFS compared to PP (P=0.039). However, no difference in OS was observed between the two surgical approaches (P=0.487). In a multivariable analysis, young age (optimal cut-off ≤63.6yrs) was associated with an OS benefit derived from TP (HR:0.44, 95%CI:0.22-0.89), whereas no significant difference was observed in elderly patients (HR:1.24, 95%CI:0.92-1.67, Pinteraction=0.007). Since overall, patients with diffuse or multifocal IPMN with an invasive component do not benefit from TP in terms of OS, the indication for TP may be individualized to young patients who have sufficient life expectancy to benefit from the prevention of secondary progression or local recurrence.

The role of intra-vascular imaging in patients undergoing intravascular lithotripsy: Insights from the COIL registry.

The role of intra-coronary imaging in patients with stent failure undergoing intravascular lithotripsy (IVL) is unclear. We aimed to assess clinical outcomes in patients undergoing IVL treatment for stent failure stratified according to the use of intra-coronary imaging and lesion complexity. This is a pre-specified subgroup analysis of patients who were included in the coronary intravascular lithotripsy in patients with stent failure (COIL) registry (international multi-centre study assessing IVL treatment for stent failure in 6 European centres). A complex lesion was defined if IVL treatment was used in the left main, true bifurcation, long lesion, or coupled with athero-ablative therapy. The primary endpoint was the composite of cardiac death, spontaneous myocardial infarction, or target vessel revascularization (TVR) at 12 months. There were 102 patients analyzed, of whom 27 (26%) patients had complex anatomy. The use of intra-coronary imaging following IVL in stent failure was more frequent in patients with complex versus Noncomplex anatomy (56% vs. 31%, p = 0.022). IVL treatment was effective in both groups, however, patients with complex anatomy had worse clinical outcomes (30% vs. 11%, p = 0.02), driven by a higher rate of TVR (26% vs. 8%, p = 0.017). In the complex group, patients who underwent intracoronary imaging post intervention had lower event rate compared to those without imaging (13% vs. 50%, p = 0.038). In patients undergoing IVL treatment for stent failure with complex coronary anatomy, the use of intra-coronary imaging was associated with fewer adverse events compared to angiography guided intervention.

Informing Decision-making for Transected Margin Reresection in Intraductal Papillary Mucinous Neoplasm-derived PDAC: An International Multicenter Study.

To assess the prognostic impact of margin status in patients with resected intraductal papillary mucinous neoplasms (IPMN)-derived pancreatic ductal adenocarcinoma (PDAC) and to inform future intraoperative decision-making on handling differing degrees of dysplasia on frozen section. The ideal oncologic surgical outcome is a negative transection margin with normal pancreatic epithelium left behind. However, the prognostic significance of reresecting certain degrees of dysplasia or invasive cancer at the pancreatic neck margin during pancreatectomy for IPMN-derived PDAC is debatable. Consecutive patients with resected and histologically confirmed IPMN-derived PDAC (2002-2022) from six international high-volume centers were included. The prognostic relevance of a positive resection margin (R1) and degrees of dysplasia at the pancreatic neck margin were assessed by log-rank test and multivariable Cox-regression for overall survival (OS) and recurrence-free survival (RFS). Overall, 832 patients with IPMN-derived PDAC were included with 322 patients (39%) having an R1-resection on final pathology. Median OS (mOS) was significantly longer in patients with an R0 status compared to those with an R1 status (65.8 vs. 26.3mo P<0.001). Patients without dysplasia at the pancreatic neck margin had similar OS compared to those with low-grade dysplasia (mOS: 78.8 vs. 66.8 months, P=0.344). However, high-grade dysplasia (mOS: 26.1mo, P=0.001) and invasive cancer (mOS: 25.0mo, P<0.001) were associated with significantly worse OS compared to no or low-grade dysplasia. Patients who underwent conversion of high-risk margins (high-grade or invasive cancer) to a low-risk margin (low-grade or no dysplasia) after intraoperative frozen section had significantly superior OS compared to those with a high-risk neck margin on final pathology (mOS: 76.9 vs. 26.1mo P<0.001). In IPMN-derived PDAC, normal epithelium or low-grade dysplasia at the neck have similar outcomes while pancreatic neck margins with high-grade dysplasia or invasive cancer are associated with poorer outcomes. Conversion of a high-risk to low-risk margin after intraoperative frozen section is associated with survival benefit and should be performed when feasible.

Impact of Adjuvant Chemotherapy on Resected Intraductal Papillary Mucinous Neoplasm-Derived Pancreatic Cancer: Results From an International Multicenter Study.

The benefit of adjuvant therapy for intraductal papillary mucinous neoplasm (IPMN)-derived pancreatic ductal adenocarcinoma (PDAC) remains unclear because of severely limited evidence. Although biologically distinct entities, adjuvant therapy practices for IPMN-derived PDAC are largely founded on pancreatic intraepithelial neoplasia-derived PDAC. We aimed to evaluate the role of adjuvant chemotherapy in IPMN-derived PDAC. This international multicenter retrospective cohort study (2005-2018) was conceived at the Verona Evidence-Based Medicine meeting. Cox regressions were performed to identify risk-adjusted hazard ratios (HR) associated with overall survival (OS). Kaplan-Meier curves and log-rank tests were employed for survival analysis. Logistic regression was performed to identify factors motivating adjuvant chemotherapy administration. A decision tree was proposed and categorized patients into overtreated, undertreated, and optimally treated cohorts. In 1,031 patients from 16 centers, nodal disease (HR, 2.88, P < .001) and elevated (≥37 to <200 µ/mL, HR, 1.44, P = .006) or markedly elevated (≥200 µ/mL, HR, 2.53, P < .001) carbohydrate antigen 19-9 (CA19-9) were associated with worse OS. Node-positive patients with elevated CA19-9 had an associated 34.4-month improvement in median OS (P = .047) after adjuvant chemotherapy while those with positive nodes and markedly elevated CA19-9 had an associated 12.6-month survival benefit (P < .001). Node-negative patients, regardless of CA19-9, did not have an associated benefit from adjuvant chemotherapy (all P > .05). Based on this model, we observed undertreatment in 18.1% and overtreatment in 61.2% of patients. Factors associated with chemotherapy administration included younger age, R1-margin, poorer differentiation, and nodal disease. Almost half of patients with resected IPMN-derived PDAC may be overtreated or undertreated. In patients with node-negative disease or normal CA19-9, adjuvant chemotherapy is not associated with a survival benefit, whereas those with node-positive disease and elevated CA19-9 have an associated benefit from adjuvant chemotherapy. A decision tree was proposed. Randomized controlled trials are needed for validation.

Sex differences in the outcome of critically Ill patients with COVID-19 - An international multicenter critical care consortium study

BackgroundSex differences in severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) susceptibility, illness severity, and hospital course are widely acknowledged. The effects of sex on outcomes experienced by patients with severe Coronavirus Disease 2019 (COVID-19) admitted to the intensive care unit (ICU) remains unknown. ObjectivesTo determine the effects of sex on ICU mortality in patients with COVID-19 MethodsThis retrospective analysis of an international multi-center prospective observational database included adults admitted to ICU for treatment of acute COVID-19 between 1st January 2020 and 30th June 2022. The primary outcome was ICU mortality. Multivariable Cox regression was used to ascertain the hazard of death (Hazard Ratio=HR) adjusted for pre-selected covariates. The secondary outcome was sex differences in complications of COVID-19 during hospital stay. ResultsOverall, 10,259 patients (3,314 females, 6,945 males) were included with a median age of 60 (interquartile range [IQR]=49–68) and 59 (IQR=49–67) years, respectively. Baseline characteristics were similar between sexes. More females were non-smokers (65% vs. 44 %, p < 0.01) and obese (39% vs. 30 %, p < 0.01), compared to males. Also, males received greater ICU intervention (mechanical ventilation, prone ventilation, vasopressors, and tracheostomy) than females. Males had a greater hazard of death (compared to females, HR=1.14; 95 % CI=1.02–1.26). Adjustment for complications during hospital stay did not alter the hazard of death (HR=1.16; 95 % CI=1.05–1.28). Males had a significantly elevated hazard of death among patients who received ECMO (HR=1.24; 95 % CI=1.01–1.53). Male sex was associated with cardiac arrest (adjusted OR [aOR]=1.37; 95 % CI=1.16–1.62) and PE (aOR=1.28; 95 % CI=1.06–1.55). ConclusionAmong patients admitted to ICU for severe COVID-19, males experienced higher severity of illness and more frequent intervention than females. Ultimately, the hazard of death was moderately elevated in males compared to females despite greater PE and cardiac arrest.

Recurrent pericarditis in older adults: Clinical and laboratory features and outcome.

Current guidelines for the diagnosis and treatment of pericarditis refer to the general adult population. Few and fragmentary data regarding recurrent pericarditis in older adults exist. Given the absence of specific data in scientific literature, we hypothesized that there might be clinical, laboratory and outcome differences between young adults and older adults affected by idiopathic recurrent pericarditis. We performed an international multicentric retrospective cohort study analyzing data from patients affected by recurrent pericarditis (idiopathic or post-cardiac injury) and referring to tertiary referral centers. Clinical, laboratory, and outcome data were compared between patients younger than 65 years (controls) and patients aged 65 or older. One hundred and thirty-three older adults and 142 young adult controls were enrolled. Comorbidities, including chronic kidney diseases, atrial fibrillation, and diabetes, were more present in older adults. The presenting symptom was dyspnea in 54.1% of the older adults versus 10.6% in controls (p < 0.001); pain in 32.3% of the older adults versus 80.3% of the controls (p < 0.001). Fever higher than 38°C was present in 33.8% versus 53.5% (p = 0.001). Pleural effusion was more prevalent in the older adults (55.6% vs 34.5%, p < 0.001), as well as severe pericardial effusion (>20 mm) (24.1% vs 12.7%, p = 0.016) and pericardiocentesis (16.5% vs 8.5%, p = 0.042). Blood leukocyte counts were significantly lower in the older adults (mean + SE: 10,227 + 289/mm3 vs 11,208 + 285/mm3, p = 0.016). Concerning therapies, NSAIDS were used in 63.9% of the older adults versus 80.3% in the younger (p = 0.003), colchicine in 76.7% versus 87.3% (p = 0.023), corticosteroids in 49.6% versus 26.8% (p < 0.001), and anakinra in 14.3% versus 23.9% (p = 0.044). Older adults affected by recurrent pericarditis show a different clinical pattern, with more frequent dyspnea, pleural effusion, severe pericardial effusion, and lower fever and lower leukocyte count, making the diagnosis sometimes challenging. They received significantly less NSAIDs and colchicine, likely due to comorbidities; they were also treated less commonly with anti-IL1 agents, and more frequently with corticosteroids.

Outcomes Of Lumen Apposing Metal Stent Placement In Patients With Surgically Altered Anatomy: A Multicenter International Experience

Introduction: While outcomes of lumen-apposing metal stents (LAMS) placement in native anatomy have been reported, data on LAMS placement in surgically altered anatomy (SAA) is sparse. We aim to assess outcomes of LAMS placement in patients with SAA for different indications. Methods: This was an international multicenter retrospective observational study at 25 tertiary-care centers through November 2023. Consecutive patients with SAA who underwent LAMS placement were included. The primary outcome was technical success defined as correct placement of LAMS. Secondary outcomes were clinical success and safety. Results: Two hundred and seventy patients (125 males; average age 61 ± 15 years) underwent LAMS placement with SAA. Procedures included EUS-directed transgastric ERCP (EDGE) and EUS-directed transenteric ERCP (EDEE) (n=82), EUS-guided entero-enterostomy (n=81), EUS-guided biliary drainage (n=57), EUS-guided drainage of peri-pancreatic fluid collections (n=48), and EUS-guided pancreaticogastrostomy (n=2). Most cases utilized AXIOS stents (n=255) compared to SPAXUS stents (n=15). Overall, technical success was 98%, clinical success was 97%, and adverse event rate was 12%. Using AGREE classification, 5 events were rated as Grade II, 21 events as Grade IIIa, and 6 events as IIIb. No difference in adverse events were noted among stent types (P=0.52). Conclusion: This study shows that placement of LAMS is associated with high technical and clinical success rates in patients with SAA. However, the rate of adverse events is noteworthy and thus these procedures should be performed by expert endoscopists at tertiary centers.

Endovascular treatment in patients with acute ischemic stroke presenting beyond 6 h after symptom onset: An international multicenter cohort study of the EVA-TRISP collaboration.

After positive findings in clinical trials the time window for endovascular thrombectomy (EVT) for patients with an acute ischemic stroke has been expanded up to 24 h from symptom onset or last seen well (LSW). We aimed to compare EVT patients' characteristics and outcomes in the early versus extended time window and to compare outcomes with the DAWN and DEFUSE 3 trial results. Consecutive EVT patients from 16 mostly European comprehensive stroke centers from the EVA-TRISP cohort were included. We compared rates of 90-day good functional outcomes (Modified Rankin Scale 0-2), symptomatic intracranial hemorrhage (sICH), and 90-day mortality between patients treated in the early (<6 h after onset or LSW) versus extended (6-24 h after onset or LSW) time windows. We included 9313 patients, of which 6876 were treated in the early and 2437 in the extended time window. National Institutes of Health Stroke Scale (NIHSS) score at presentation was lower in patients treated in the extended time window (median 13 [IQR 7-18] vs 15 [IQR 9-19], p < 0.001). The percentage of patients with good functional outcome was slightly lower in the extended time window (37.4% vs 42.2%, p < 0.001). However, rates of successful recanalization, sICH, and mortality were similar. Good functional outcome rates after EVT were slightly lower for patients in the extended window in the EVA-TRISP cohort as compared to DAWN and DEFUSE 3. According to this large multicenter cohort study reflecting daily clinical practice, EVT use in the extended time window appears safe and effective.

Analysis of the Results and Significance of the Independent Prospective Multicenter International Study “ACCRED-ROSOMED”

The study analyzed feedback from the accreditation subcommittees members and determined the significance of the multicenter prospective international study “ACCRED-ROSOMED”. The analysis included 410 questionnaires from APC members from 11 regions of the Russian Federation during the work of the subcommissions in 2022-24. The following issues were analyzed: composition, awareness, training, motivational factors of APC members, the degree of satisfaction with OSCE stations and the training of accredited persons, and other issues. The significance of the ACCRED-ROSOMED study for the further development of professional assessment of specialists and the need for further research was demonstrated.

Outcome of Minimally Invasive and Open Pancreatoduodenectomy in Patients with Intestinal- and Pancreatobiliary Subtype Ampullary Cancer: An International Multicenter Cohort Study.

To compare minimally invasive and open pancreatoduodenectomy in different subtypes of ampullary adenocarcinoma. Ampullary adenocarcinoma (AAC) is widely seen as the best indication for minimally invasive pancreatoduodenectomy (MIPD) due to the lack of vascular involvement and dilated bile and pancreatic duct. However, it is unknown whether outcomes of MIPD for AAC differ between the pancreatobiliary (AAC-PB) and intestinal (AAC-IT) subtypes as large studies are lacking. This is an international cohort study, encompassing 27 centers from 12 countries. Outcome of MIPD and open pancreatoduodenectomy (OPD) were compared in patients with AAC-IT and AAC-PB. Primary end points were R1 rate, lymph node yield, and 5-year overall survival (5yOS). Overall, 1187 patients after MIPD for AAC were included, of whom 572 with AAC-IT (62 MIPD, 510 OPD) and 615 with AAC-PB (41 MIPD and 574 OPD). The rate of R1 resection was not significantly different between MIPD and OPD for both AAC-IT (3.4% vs 6.9%, P=0,425) and AAC-PB (9.8% vs 14.9%, P=0,625). AAC-IT, more lymph nodes were resected with MIPD group (19 vs 16, P=0.007), compared to OPD. The 5y-OS did not differ after MIPD and OPD for both AAC-IT (56.8% vs 59.5%, P=0.827 and AAC-PB (52.5% vs 44.4%, P=0.357). The rates of surgical complication between MIPD and OPD did not differ between AmpIT and AmpPB. This international multicenter study found no differences in outcomes between MIPD and OPD for AAC-IT and AAC-PB. MIPD and OPD demonstrated comparable outcomes in oncological resection, survival and surgical outcomes for both subtypes of AAC.

Single ventricle palliation in congenitally corrected transposition of the great arteries: an international multicentre study.

BackgroundSingle ventricle palliation (SVP) may be performed in patients with congenitally corrected transposition of the great arteries (ccTGA) due to either hypoplasia of one ventricle, or anatomic complexity rendering biventricular repair unfeasible. There have been only a few, small studies of the outcomes of SVP in the setting of ccTGA. MethodsA multicentre, international, retrospective cohort study of patients with ccTGA undergoing SVP was conducted in 29 tertiary hospitals in 6 countries from 1990 to 2018. ResultsA total of 194 patients with ccTGA underwent SVP. A functionally univentricular heart was present in 62.4% (121/194). Patients with two good-sized ventricles had more laterality defects (50.7% v 28.1%, p=0.002). Fontan completion was achieved in 80.3% (155/194). A tricuspid valve surgery was performed in 9.3% (18/194). Survival was 97.4% (95% CI: 92.1–99.2%) at 15 years in the univentricular cohort, while it was 89.8% (95% CI: 78.0–95.5%) at 15 years in those with two adequate ventricles, p = 0.05. At last follow-up 11.5% of patients had heart failure, while 6.0% had moderate or greater systemic RV dysfunction and 8.4% exhibited moderate or greater tricuspid regurgitation. In multivariable analysis, aortic coarctation or hypoplasia (HR=7.7, p=0.005) was associated with mortality. ConclusionsSingle ventricle palliation in patients with ccTGA is associated with excellent long-term survival and low rates of heart failure and atrioventricular valve failure. In patients who would require complex surgery to achieve a biventricular repair, SVP appears to be a good alternative.

379P Safety and efficacy of trastuzumab deruxtecan and concomitant radiation therapy in patients with metastatic breast cancer: A multicentre international retrospective cohort study

379P Safety and efficacy of trastuzumab deruxtecan and concomitant radiation therapy in patients with metastatic breast cancer: A multicentre international retrospective cohort study

Has robot-assisted pyeloplasty reached outcome parity with laparoscopic pyeloplasty in children

Has robot-assisted pyeloplasty reached outcome parity with laparoscopic pyeloplasty in children <15kg? A Paediatric YAU international multi-center study.

765. PATTERNS, TIMING, AND SURVIVAL OF RECURRENCE FOLLOWING SURGERY FOR ESOPHAGEAL ADENOCARCINOMA IN THE EUROPEAN MULTICENTRE ENSURE STUDY

Abstract Background After surgery for esophageal cancer approximately half of patients will develop disease recurrence. A more accurate and detailed understanding of the pattern, timing, treatment and prognosis of initial recurrence sites can guide improvements in surveillance and therapy. Therefore, the aim of this study was to accurately describe the pattern and timing of esophageal cancer recurrence, and to assess the distinct survival patterns of these recurrence locations. Methods This study included all patients who underwent surgical resection for esophageal and junctional adenocarcinoma registered in the ENSURE study. ENSURE was an international multicenter study of consecutive patients undergoing surgery for esophageal and esophagogastric junction cancers between 2009 and 2015 across 20 centers in Europe and Canada (NCT03461341). The first recurrence site was recorded and recurrence-free survival (RFS) was estimated using Kaplan-Meier curves. Sites of first recurrence were stratified into different groups and survival outcomes post recurrence detection were estimated using Kaplan-Meier curves. Results Of 3397 eligible patients, 1310 patients had disease recurrence with comprehensive follow-up data available (median RFS of 12.1 months). First recurrence was detected at multiple distant sites (n=469; 37.3%) or at a single distant site (n=463; 33.7%), while isolated local recurrence occurred in 189 (14.4%) patients. Liver-only recurrence occurred significantly earlier (median 9.0 months), while lung-only (15.2 months) and local-only occurred later (17.8 months). Patients with multiple-sites and liver-only recurrence had significant worse median post recurrence survival (7.4 and 8.3 months, respectively) when compared with lung- or local-only recurrence (10.4 and 15.9 months, respectively). Conclusion This study demonstrates that specific recurrence locations of esophageal cancer possess distinct RFS curves. Furthermore, specific recurrence locations result in different post recurrence survival outcomes. This information can help guide improvements in surveillance after esophageal cancer surgery and decisions regarding treatment of esophageal cancer recurrence.

Prosthetic Joint Infections due to Candida Species: A Multicenter International Study.

Prosthetic joint infection (PJI) caused by Candida spp is a severe complication of arthroplasty. We investigated the outcomes of Candida PJI. This was a retrospective observational multinational study including patients diagnosed with Candida-related PJI between 2010 and 2021. Treatment outcome was assessed at 2-year follow-up. A total of 269 patients were analyzed. Median age was 73.0 (interquartile range [IQR], 64.0-79.0) years; 46.5% of patients were male and 10.8% were immunosuppressed. Main infection sites were hip (53.0%) and knee (43.1%), and 33.8% patients had fistulas. Surgical procedures included debridement, antibiotics, and implant retention (DAIR) (35.7%), 1-stage exchange (28.3%), and 2-stage exchange (29.0%). Candida spp identified were Candida albicans (55.8%), Candida parapsilosis (29.4%), Candida glabrata (7.8%), and Candida tropicalis (5.6%). Coinfection with bacteria was found in 51.3% of cases. The primary antifungal agents prescribed were azoles (75.8%) and echinocandins (30.9%), administered for a median of 92.0 (IQR, 54.5-181.3) days. Cure was observed in 156 of 269 (58.0%) cases. Treatment failure was associated with age >70 years (OR, 1.811 [95% confidence interval {CI}: 1.079-3.072]), and the use of DAIR (OR, 1.946 [95% CI: 1.157-3.285]). Candida parapsilosis infection was associated with better outcome (OR, 0.546 [95% CI: .305-.958]). Cure rates were significantly different between DAIR versus 1-stage exchange (46.9% vs 67.1%, P = .008) and DAIR versus 2-stage exchange (46.9% vs 69.2%, P = .003), but there was no difference comparing 1- to 2-stage exchanges (P = .777). Candida PJI prognosis seems poor, with high rate of failure, which does not appear to be linked to immunosuppression, use of azoles, or treatment duration.

Real world outcomes of patients with radioiodine-refractory differentiated thyroid cancer (RAI-R DTC) treated in 1l with lenvatinib 24 mg: an international multicenter real-world study in europe and canada

Real world outcomes of patients with radioiodine-refractory differentiated thyroid cancer (RAI-R DTC) treated in 1l with lenvatinib 24 mg: an international multicenter real-world study in europe and canada

Survey of CT radiation doses and iodinated contrast medium administration: an international multicentric study.

To assess the relationship between intravenous iodinated contrast media (ICM) administration usage and radiation doses for contrast-enhanced (CE) CT of head, chest, and abdomen-pelvis (AP) in international, multicenter settings. Our international (n = 16 countries), multicenter (n = 43 sites), and cross-sectional (ConRad) study had two parts. Part 1: Redcap survey with questions on information related to CT and ICM manufacturer/brand and respective protocols. Part 2: Information on 3,258 patients (18-96 years; M:F 1654:1604) who underwent CECT for a routine head (n = 456), chest (n = 528), AP (n = 599), head CT angiography (n = 539), pulmonary embolism (n = 599), and liver CT examinations (n = 537) at 43 sites across five continents. The following information was recorded: hospital name, patient age, gender, body mass index [BMI], clinical indications, scan parameters (number of scan phases, kV), IV-contrast information (concentration, volume, flow rate, and delay), and dose indices (CTDIvol and DLP). Most routine chest (58.4%) and AP (68.7%) CECT exams were performed with 2-4 scan phases with fixed scan delay (chest 71.4%; AP 79.8%, liver CECT 50.7%) following ICM administration. Most sites did not change kV across different patients and scan phases; most CECT protocols were performed at 120-140 kV (83%, 1979/2685). There were no significant differences between radiation doses for non-contrast (CTDIvol 24 [16-30] mGy; DLP 633 [414-702] mGy·cm) and post-contrast phases (22 [19-27] mGy; 648 [392-694] mGy·cm) (p = 0.142). Sites that used bolus tracking for chest and AP CECT had lower CTDIvol than sites with fixed scan delays (p < 0.001). There was no correlation between BMI and CTDIvol (r2 ≤ - 0.1 to 0.1, p = 0.931). Our study demonstrates up to ten-fold variability in ICM injection protocols and radiation doses across different CT protocols. The study emphasizes the need for optimizing CT scanning and contrast protocols to reduce unnecessary contrast and radiation exposure to patients. The wide variability and lack of standardization of ICM media and radiation doses in CT protocols suggest the need for education and optimization of contrast usage and scan factors for optimizing image quality in CECT. There is a lack of patient-centric CT protocol optimization taking into consideration mainly patients' size. There is a lack of correlation between ICM volume and CT radiation dose across CT protocol. A ten-fold variation in iodine-load for the same CT protocol in sites suggests a lack of standardization.