ABSTRACT
The purpose of this study is to investigate if there was a delay in high-risk MRI breast cancer screening in our local region, if this delay is ongoing despite COVID-19 vaccinations, and if demographic and socioeconomic factors are associated with these delays. Six-hundred and sixty-five high-risk breast patients from 23 January 2018-30 September 2021 were included. Delays were determined by comparing the time in between each patients' MRI screening exams prior to the COVID-19 pandemic to the time in between MRI screening exams during the height of the COVID-19 pandemic as well as the time in between exams when our patients started receiving vaccinations. Delays were analyzed via logistical regression with demographic and socioeconomic factors to determine if there was an association between these factors and delays. Significant time delays in between MRI screening exams were found between the pre-COVID timeframe compared to during the height of COVID. Significant time delays also persisted during the timeframe after patients started getting vaccinations. There were no associations with delays and socioeconomic or demographic factors. Significant time delays were found in between MRI high-risk breast cancer screening examinations due to the COVID-19 pandemic. These delays were not exacerbated by demographic or socioeconomic factors.
Subject(s)
Breast Neoplasms , COVID-19 , Breast Neoplasms/diagnostic imaging , Early Detection of Cancer , Female , Humans , Magnetic Resonance Imaging , Pandemics , Socioeconomic FactorsABSTRACT
PURPOSE: The multifaceted nature of learning in diagnostic radiology residency requires a variety of assessment methods. However, the scope and quality of assessment tools has not been formally examined. A scoping review was performed to identify assessment tools available for radiology resident training and to evaluate the validity of these tools. METHODS: A literature search was conducted through multiple databases and on-line resources. Inclusion criteria were defined as any tool used in assessment of radiology resident competence. Data regarding residents, evaluators and specifics of each tool was extracted. Each tool was subjected through a validation process with a customized rating scale using the 5 categories of validity: content, response process, internal structure, relations to other variables, and consequences. RESULTS: The initial search returned 447 articles; 35 were included. The most evaluated competency being overall knowledge (31%), most common published journal was Academic Radiology (24%); evaluations were most commonly set in the United States (57%). In terms of validation, we found low adherence to modern integrated validity, with 34% of studies including a definition of validity. When specifically examining the 5 domains of validation evidence presented, most were either absent or of low rigor (70%). Only one study presented a modern definition of validation (3%, 1/35). CONCLUSION: We identified 35 evaluation tools covering a variety of competency areas. However, few of these tools have been validated. Development of new validated assessment tools or validation of existing tools is essential for the ongoing transition to a competency-based curriculum.
Subject(s)
Clinical Competence/statistics & numerical data , Education, Medical, Graduate/methods , Educational Measurement/methods , Internship and Residency/methods , Radiology/education , Curriculum , Humans , United StatesABSTRACT
INTRODUCTION: In March 2020, the World Health Organization declared a pandemic caused by a novel coronavirus. Public information created awareness as well as concern in the general population. There has been a reported decrease in the number of patients attending emergency departments (ED) during the pandemic. This is the first study to determine differences in the types of presenting illnesses, severity, and rate of resultant surgical intervention during the pandemic. METHODS AND MATERIALS: We carried out a retrospective, observational cohort study comparing two groups of patients attending the ED at our tertiary-care academic hospital. A historical comparison cohort was obtained by reviewing the number of patients referred by the ED for abdominal CT between March 15 and April 15, 2020, compared with March 15 and April 15, 2019. CT reports were reviewed; primary pathologies, complications, and subsequent surgical intervention were documented and compared between the two groups. RESULTS: In all, 733 patients were included in the 2019 cohort, and 422 patients were included in the 2020 cohort. In 2019, 32.7% had positive CT findings, increasing to 50.5% in 2020. The number of complications increased from 7.9% to 19.7%. The rate requiring surgical intervention increased from 26.3% to 47.6% in 2020. CONCLUSION: To date, there is little published data regarding the presentation and severity of illnesses during the coronavirus disease 2019 pandemic. This information has important public health implications, highlighting the need to educate patients to continue to present to hospital services during such crises, including if a purported second wave of COVID-19 arises.
Subject(s)
Abdomen, Acute/diagnostic imaging , COVID-19/epidemiology , Emergency Service, Hospital , Tomography, X-Ray Computed , Abdomen, Acute/complications , Abdomen, Acute/surgery , Adult , Female , Humans , Male , Middle Aged , Pandemics , Severity of Illness IndexABSTRACT
Background Recent investigations have identified a faster time to publication for imaging studies with higher diagnostic test accuracy (DTA), but it is unknown whether such studies are more likely to be published. A higher probability of full-text publication for studies with higher DTA could have negative consequences on clinical decision making and patient care. Purpose To evaluate the proportion of imaging diagnostic accuracy studies presented as conference abstracts that reach full-text publication and to identify whether there is an association between diagnostic accuracy and full-text publication in peer-reviewed journals within 5 years after abstract submission. Materials and Methods Diagnostic accuracy research abstracts presented at the Radiological Society of North America (RSNA) Annual Meeting in 2011 and 2012 were evaluated between September 1, 2017, and January 11, 2018. Sensitivity and specificity from the abstracts were used to calculate the Youden index (sensitivity + specificity-1); additional abstract characteristics were extracted. To identify full-text publications within 5 years after abstract submission, PubMed and Google Scholar were searched, and authors were contacted. Logistic regression analysis was used to assess for associations between higher diagnostic accuracy and full-text publication. Results A total of 7970 abstracts were evaluated, and 405 were included. Of these, 288 (71%) reached full-text publication within 5 years after abstract submission. Logistic regression analysis accounting for several confounding variables failed to show an association between reported Youden index in the conference abstract and probability of full-text publication (odds ratio, 1.01; 95% confidence interval: 0.99, 1.02; P = .21). Conclusion More than a quarter of abstracts presented at the RSNA Annual Meeting do not reach full-text publication in peer-reviewed journals. The magnitude of reported diagnostic accuracy was not associated with full-text publication, which is consistent with results of diagnostic accuracy studies in other medical specialties. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Fielding in this issue.
Subject(s)
Abstracting and Indexing/statistics & numerical data , Congresses as Topic/statistics & numerical data , Publication Bias/statistics & numerical data , Abstracting and Indexing/standards , Congresses as Topic/standards , Humans , Peer Review , Radiology , Reproducibility of Results , Sensitivity and Specificity , Societies, MedicalABSTRACT
OBJECTIVES: Medical three-dimensional (3D) printing, the fabrication of handheld models from medical images, has the potential to become an integral part of otolaryngology-head and neck surgery (Oto-HNS) with broad impact across its subspecialties. We review the basic principles of this technology and provide a comprehensive summary of reported clinical applications in the field. METHODS: Standard bibliographic databases (MEDLINE, Embase, Cumulative Index to Nursing and Allied Health Literature, Web of Science, and The Cochrane Central Registry for Randomized Trials) were searched from their inception to May 2018 for the terms: "3D printing," "three-dimensional printing," "rapid prototyping," "additive manufacturing," "computer-aided design," "bioprinting," and "biofabrication" in various combinations with the terms: "ptolaryngology," "head and neck surgery," and "otology." Additional articles were identified from the references of retrieved articles. Only studies describing clinical applications of 3D printing were included. RESULTS: Of 5,532 records identified through database searching, 87 articles were included for qualitative synthesis. Widespread implementation of 3D printing in Oto-HNS is still at its infancy. Nonetheless, it is increasingly being utilized across all subspecialties from preoperative planning to design and fabrication of patient-specific implants and surgical guides. An emerging application considered highly valuable is its use as a teaching tool for medical education and surgical training. CONCLUSIONS: As technology and training standards evolve and as healthcare moves toward personalized medicine, 3D printing is emerging as a key technology in patient care in Oto-HNS. Treating physicians and surgeons who wish to stay abreast of these developments will benefit from a fundamental understanding of the principles and applications of this technology. Laryngoscope, 129:2045-2052, 2019.
Subject(s)
Otolaryngology/instrumentation , Printing, Three-Dimensional , Surgery, Computer-Assisted/instrumentation , Biocompatible Materials , Bioprinting , Computer-Aided Design , Humans , Models, Anatomic , Patient Care Planning , Prostheses and ImplantsABSTRACT
OBJECTIVES: To assess the risk of citation bias in imaging diagnostic accuracy research by evaluating whether studies with higher accuracy estimates are cited more frequently than those with lower accuracy estimates. METHODS: We searched Medline for diagnostic accuracy meta-analyses published in imaging journals from January 2005 to April 2016. Primary studies from the meta-analyses were screened; those assessing the diagnostic accuracy of an imaging test and reporting sensitivity and specificity were eligible for inclusion. Studies not indexed in Web of Science, duplicates, and inaccessible articles were excluded. Topic (modality/subspecialty), study design, sample size, journal impact factor, publication date, times cited, sensitivity, and specificity were extracted for each study. Negative binomial regression was performed to evaluate the association of citation rate (times cited per month since publication) with Youden's index (sensitivity + specificity -1), highest sensitivity, and highest specificity, controlling for the potential confounding effects of modality, subspecialty, impact factor, study design, sample size, and source meta-analysis. RESULTS: There were 1016 primary studies included. A positive association between Youden's index and citation rate was present, with a regression coefficient of 0.33 (p = 0.016). The regression coefficient for sensitivity was 0.41 (p = 0.034), and for specificity, 0.32 (p = 0.15). CONCLUSION: A positive association exists between diagnostic accuracy estimates and citation rates, indicating that there is evidence of citation bias in imaging diagnostic accuracy literature. Overestimation of imaging test accuracy may contribute to patient harm from incorrect interpretation of test results. KEY POINTS: ⢠Studies with higher accuracy estimates may be cited more frequently than those with lower accuracy estimates. ⢠This citation bias could lead clinicians, reviews, and clinical practice guidelines to overestimate the accuracy of imaging tests, contributing to patient harm from incorrect interpretation of test results.
Subject(s)
Bibliometrics , Diagnostic Imaging/standards , Bias , Humans , Journal Impact Factor , Meta-Analysis as Topic , Research Design , Sensitivity and SpecificityABSTRACT
INTRODUCTION: Radiologists and other specialty consultants play a role in diagnosing patients with acute abdominal conditions. Numerous Computed Tomography (CT) protocols are available and radiologists' choices are influenced by the clinical history provided. We hypothesize that the quality of the initial communication between referring physicians and radiologists greatly affects the utilization of health resources and subsequent patient care. The purpose of this pilot study was to employ a grading system to quantitatively evaluate a provided history. We also sought to evaluate inter-rater reliability by having radiologists evaluate sample histories and finally, to assess whether the quality of history has an impact on the number of CT protocols radiologists choose as potentially appropriate, with less potential protocols being seen as a positive outcome. METHODS: Four reviewers, (2 attendings and 2 residents) evaluated 350 consecutive clinical histories provided for patients presenting to a tertiary care Emergency Department (ED) between September-October, 2012. Reviewers graded histories on a 5-point scale using 4 categories of criteria. This includes a) presenting complaint, b) relevant past medical history or symptom evolution, c) objective laboratory or prior examination results and d) differential diagnosis. RESULTS: There was substantial agreement among all four reviewers when evaluating the quality of history, ICC 0.61, (95% CI 0.48-0.71). In particular, agreement amongst attending radiologists was substantial, with ICC 0.69 (0.48-0.80). Significant negative correlation was observed between history grade and number of potentially appropriate protocols in 3 of 4 reviewers (Spearman's rho: -0.394, -0.639, -0.864, p <0.0001 for these reviewers). This correlation was significantly stronger for attending radiologists (Spearman's rho: -0.763, 95% CI -0.7933 to -0.731; p<0.0001). Agreement was poor among reviewers when asked exactly how many protocols could potentially be used to answer the clinical question based on provided history, ICC 0.08, (95% -0.03-0.13). CONCLUSION: Although there is still variability in radiologists' approach to protocoling urgent studies, a more comprehensive requisition history narrowed the number of protocols considered.
Subject(s)
Abdomen/diagnostic imaging , Choice Behavior , Emergency Service, Hospital/statistics & numerical data , Pelvis/diagnostic imaging , Tomography, X-Ray Computed/statistics & numerical data , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Observer Variation , Pilot Projects , Radiologists , Retrospective Studies , Young AdultABSTRACT
OBJECTIVES: The purpose of our study was to investigate authorship trends in radiology journals, and whether International Committee of Medical Journal Editors (ICMJE) recommendations have had an impact on these trends. A secondary objective was to explore other variables associated with authorship trends. METHODS: A retrospective, bibliometric analysis of 49 clinical radiology journals published from 1946-2013 was conducted. The following data was exported from MEDLINE (1946 to May 2014) for each article: authors' full name, year of publication, primary author institution information, language of publication and publication type. Microsoft Excel Visual Basics for Applications scripts were programmed to categorize extracted data. Statistical analysis was performed to determine the overall mean number of authors per article over time, impact of ICMJE guidelines, authorship frequency per journal, country of origin, article type and language of publication. RESULTS: 216,271 articles from 1946-2013 were included. A univariate analysis of the mean authorship frequency per year of all articles yielded a linear relationship between time and authorship frequency. The mean number of authors per article in 1946 (1.42) was found to have increased consistently by 0.07 authors/ article per year (R² = 0.9728, P<0.001) to 5.79 authors/article in 2013. ICMJE guideline dissemination did not have an impact on this rise in authorship frequency. There was considerable variability in mean authors per article and change over time between journals, country of origin, language of publication and article type. CONCLUSION: Overall authorship for 49 radiology journals across 68 years has increased markedly with no demonstrated impact from ICMJE guidelines. A higher number of authors per article was seen in articles from: higher impact journals, European and Asian countries, original research type, and those journals who explicitly endorse the ICMJE guidelines.
Subject(s)
Authorship , Periodicals as Topic/statistics & numerical data , Radiology/statistics & numerical data , Authorship/standards , Bibliometrics , Humans , Periodicals as Topic/standardsABSTRACT
OBJECTIVE: The purpose of this study is to evaluate the rate of duplicate publication in radiology journals. The secondary objective is to evaluate the sensitivity of iThenticate. MATERIALS AND METHODS: From January 1993 to December 2013, Déjà Vu (a database of highly similar citations) and PubMed were used to search for similar citations in 53 radiology journals. Citations were screened independently by two reviewers and verified by a third using predefined criteria to determine true cases of duplicate publication. The overall rate of duplicate publication was calculated; analysis of rate by journal, impact factor, and publication year was performed. The sensitivity of iThenticate was evaluated by analyzing all identified duplicate publications. RESULTS: From 128,818 citations in the included journals, 1786 (Déjà Vu) and 104 (PubMed) were flagged as potential duplicates. Of these, 248 (226 from Déjà Vu and 22 from PubMed) were classified as true duplicate publications after application of our criteria. The overall rate was 1.92/1000 citations; it varied widely across journals from zero to over 10/1000 citations, showed no correlation with impact factor (R(2) = 0.06; p = 0.093), and no change over time (R(2) = 0.28; p = 0.515). iThenticate flagged 153 of 248 (61.9%) duplicates as "possible duplicates" (defined as overall percentage match > 30%) and identified the corresponding duplicate citation pair in 140 of 248 (56.7%) cases; in 98 of these, the duplicate citation pair was the highest percentage similarity match. CONCLUSION: Duplicate publications in radiology journals are uncommon. The rate varies widely between journals, but was not associated with journal impact factor and did not change over time. iThenticate shows promise for identification of duplicate publications; however, refinements may be necessary to maximize its effectiveness.
Subject(s)
Duplicate Publications as Topic , Radiology , Bibliometrics , Databases, Bibliographic , Humans , MEDLINEABSTRACT
PURPOSE: To evaluate whether presence of a CT scanner in the emergency department (ED) improves ED workflow by decreasing time between imaging requisition and completion, and time to final patient disposition. METHODS: Institutional review board approval was obtained for this retrospective study conducted on 2,142 consecutive, acute thoracic, abdomino- pelvic imaging requests from 2 ED hospital campuses affiliated with the same academic institution, August 1 to October 31, 2012. Of these patients, only 1,696 had complete records and were used for analysis. One hospital had a CT scanner in the ED; the other was in the radiology department, 300 meters from the ED. Patients were stratified based on acuity of CT indication, interpreting radiologist training level, and time of day. Time points were compared between hospitals: (1) time of CT requisition receipt to time of scan initiation (2) time from scan initiation to time of preliminary report by resident or fellow, or verbally by staff to the ED; and (3) time of CT requisition receipt to time of final patient disposition. RESULTS: Decreases in time, favoring the institution with the ED CT scanner, are 16 min (P < .0001); 15 minutes (P < .0001); and 19 minutes (P < .04) for the 3 times, respectively. Significant differences were seen in morning and overnight shifts and for CT reporting times with higher radiology levels of training (20 min, P = .04; and 18 min, P < .0001 for staff and postgraduate year-5 residents, respectively). CONCLUSIONS: Presence of an ED CT scanner is associated with decreases in time to CT scan completion, radiologic interpretation, and patient disposition.
Subject(s)
Efficiency, Organizational/statistics & numerical data , Emergency Service, Hospital/statistics & numerical data , Patient Discharge Summaries/statistics & numerical data , Referral and Consultation/statistics & numerical data , Tomography, X-Ray Computed/statistics & numerical data , Workflow , Documentation/statistics & numerical data , Medical Records Systems, Computerized/statistics & numerical data , Ontario/epidemiology , Time FactorsABSTRACT
Hand-held three dimensional models of the human anatomy and pathology, tailored-made protheses, and custom-designed implants can be derived from imaging modalities, most commonly Computed Tomography (CT). However, standard DICOM format images cannot be 3D printed; instead, additional image post-processing is required to transform the anatomy of interest into Standard Tessellation Language (STL) format is needed. This conversion, and the subsequent 3D printing of the STL file, requires a series of steps. Initial post-processing involves the segmentation-demarcation of the desired for 3D printing parts and creating of an initial STL file. Then, Computer Aided Design (CAD) software is used, particularly for wrapping, smoothing and trimming. Devices and implants that can also be 3D printed, can be designed using this software environment. The purpose of this article is to provide a tutorial on 3D Printing with the test case of complex congenital heart disease (CHD). While the infant was born with double outlet right ventricle (DORV), this hands-on guide to be featured at the 2015 annual meeting of the Radiological Society of North America Hands-on Course in 3D Printing focused on the additional finding of a ventricular septal defect (VSD). The process of segmenting the heart chambers and the great vessels will be followed by optimization of the model using CAD software. A virtual patch that accurately matches the patient's VSD will be designed and both models will be prepared for 3D printing.
ABSTRACT
Asthma represents one of the most common chronic conditions encountered in primary care and diagnosis should be confirmed objectively with the demonstration of variable airflow obstruction. As many asthmatics have normal lung function at the time of clinical presentation, objective confirmation of airflow limitation may be challenging. Fluctuations in airflow obstruction can be documented with simple office spirometry after bronchodilator challenge, home monitoring of peak expiratory flow and bronchoconstriction induced by spasmogens such as methacholine. We present a case highlighting the challenge of objective confirmation of asthma diagnosis in primary care and provide a critical review of the diagnostic approaches highlighted above. Our aim is to provide a pragmatic interpretation of the available literature with a view to assisting clinicians in selecting the diagnostic test best suited for individualised patient encounters.
Subject(s)
Asthma/diagnosis , Diagnostic Techniques, Respiratory System/standards , Female , Humans , Middle Aged , Primary Health CareABSTRACT
BACKGROUND: The Internet is used increasingly by providers as a tool for disseminating pain-related health information and by patients as a resource about health conditions and treatment options. However, health information on the Internet remains unregulated and varies in quality, accuracy and readability. The objective of this study was to determine the quality of pain websites, and explain variability in quality and readability between pain websites. METHODS: Five key terms (pain, chronic pain, back pain, arthritis, and fibromyalgia) were entered into the Google, Yahoo and MSN search engines. Websites were assessed using the DISCERN instrument as a quality index. Grade level readability ratings were assessed using the Flesch-Kincaid Readability Algorithm. Univariate (using alpha = 0.20) and multivariable regression (using alpha = 0.05) analyses were used to explain the variability in DISCERN scores and grade level readability using potential for commercial gain, health related seals of approval, language(s) and multimedia features as independent variables. RESULTS: A total of 300 websites were assessed, 21 excluded in accordance with the exclusion criteria and 110 duplicate websites, leaving 161 unique sites. About 6.8% (11/161 websites) of the websites offered patients' commercial products for their pain condition, 36.0% (58/161 websites) had a health related seal of approval, 75.8% (122/161 websites) presented information in English only and 40.4% (65/161 websites) offered an interactive multimedia experience. In assessing the quality of the unique websites, of a maximum score of 80, the overall average DISCERN Score was 55.9 (13.6) and readability (grade level) of 10.9 (3.9). The multivariable regressions demonstrated that website seals of approval (P = 0.015) and potential for commercial gain (P = 0.189) were contributing factors to higher DISCERN scores, while seals of approval (P = 0.168) and interactive multimedia (P = 0.244) contributed to lower grade level readability, as indicated by estimates of the beta coefficients. CONCLUSION: The overall quality of pain websites is moderate, with some shortcomings. Websites that scored high using the DISCERN questionnaire contained health related seals of approval and provided commercial solutions for pain related conditions while those with low readability levels offered interactive multimedia options and have been endorsed by health seals.
Subject(s)
Consumer Health Information/standards , Information Services/standards , Internet , Pain , Patient Education as Topic/standards , Chronic Disease , Comprehension , Humans , Information Dissemination/methods , Quality Assurance, Health Care/standards , Regression AnalysisABSTRACT
BACKGROUND: Our objective was to identify morphologic trends in elective and emergency endovascular aneurysm repair (EVAR). This work will inform hospitals with endovascular programs about the diameters and lengths of endostents that should be available to efficiently care for patients with these conditions. METHODS: We performed a retrospective review of patients undergoing elective (n = 127) and emergency (n = 17) EVAR. Using computed tomography and 3-dimensional reconstructions, we evaluated the following: diameters of the aneurysm (D3), the aorta at the superior mesenteric (D1) and renal (D2a,b,c; 3 levels) levels, the iliac arteries (D5a,b; right and left) and the aortic bifurcation (D4); lengths from the lowest renal artery to the distal aspect of the aortic neck (H1), to the aortic bifurcation (H3), to the right and left iliac bifurcations (H4a,b); and angles of the origin of the common iliac arteries on the transverse plane (A1). We used descriptive statistics of trends within groups and independent sample t tests. RESULTS: In elective and emergency aneurysm repair, D2max (26, standard deviation [SD] 3, mm v. 30.7 [SD 3] mm), D5a (16 [SD 4.7] mm v. 19.3 [SD 5] mm), D5b (15.3 [SD 4] mm v. 18.1 [SD 3.6] mm), H1 (25.6 [SD 8.6] mm v. 18 [SD 2] mm), H4a (173 [SD 22] mm v. 189.5 [SD 22] mm) and H4b (174 [SD 25] mm v. 190 [SD 14] mm) were significantly different between the 2 groups (p = 0.001, p = 0.006, p = 0.007, p < 0.001, p = 0.05 and p = 0.01, respectively). H3 (118 [SD 17] mm v. 121.5 [SD 13.5] mm) was not significantly different (p = 0.40). In elective patients, A1 identified the right common iliac more frequently anterior relative to the left common iliac (mean 23 degrees , SD 16 degrees). CONCLUSION: Significant anatomic differences between elective and emergency patients will require hospitals to stock separate endovascular devices to treat abdominal aortic aneurysms in both groups.
Subject(s)
Aorta, Abdominal/pathology , Aortic Aneurysm, Abdominal/pathology , Aortic Aneurysm, Abdominal/surgery , Iliac Artery/pathology , Prosthesis Design , Aorta, Abdominal/diagnostic imaging , Blood Vessel Prosthesis Implantation , Elective Surgical Procedures , Emergency Treatment , Humans , Iliac Artery/diagnostic imaging , Prosthesis Fitting , Retrospective Studies , Stents , Tomography, X-Ray ComputedABSTRACT
OBJECTIVES: To examine the relationship between the orientation of the iliac arteries in infrarenal aortic aneurysms and its effect on the cannulation of the contralateral limb of a bifurcated stent graft system (SGS) used for endovascular aneurysm repair (EVAR). METHODS: This is a retrospective review of prospectively collected data in 100 consecutive patients treated with EVAR using the Zenith device (Cook Medical Inc., Bloomington, Indiana, USA). We collected data on reciprocal orientation between the origins of the common iliac arteries (OOCIA) on an axial plane, the common femoral artery (right or left) used to deliver the main body of the SGS (access side), and the cannulation time of the contralateral limb. The latter was defined as the time elapsed between the introduction of the selective catheter in the contralateral iliac artery to the time of successful cannulation of the contralateral limb of the SGS. Using an Aquarius workstation (v. 3.5; TeraRecon Inc, San Mateo, Calif), the OOCIA was measured establishing the center of the origin of the right and left common iliac arteries and joining them using a straight line. A horizontal line was then drawn through the origin of the right common iliac artery. The angle created by these two lines was defined as "zero," "positive," or "negative." We examined the relations between cannulation time, access side, and OOCIA using t tests and a multivariate regression analysis. RESULTS: In 84 patients, the origin of the right common iliac artery was in an anterior position compared with the left; in 16, the origin of the right and left were on the same horizontal line; and the right common iliac artery was posterior in none of the patients. The main body of the prosthesis was delivered using the left femoral artery in 52 patients and the right in 48. When all patients were considered, cannulation time was shorter when the main body of the bifurcated prosthesis was delivered through the left femoral artery (9.3 +/- 5.8 minutes vs 15.4 +/- 7.2 minutes, P < .0001). This effect was more pronounced when only patients with the left common iliac artery located posteriorly were examined (9.3 +/- 5.80 minutes vs 16.4 +/- 7.6 minutes, P < .0001). There was no correlation between increasing negativity of the OOCIA angle and cannulation time, regardless of access side. CONCLUSION: We have shown that in patients with infrarenal aortic aneurysms, the origin of the right iliac artery is often anterior compared with the left and that cannulation time of the contralateral limb is shorter when the main body of the prosthesis is delivered from the left.