ESR essentials: MRI of the knee-practice recommendations by ESSR.

Many studies and systematic reviews have been published about MRI of the knee and its structures, discussing detailed anatomy, imaging findings, and correlations between imaging and clinical findings. This paper includes evidence-based recommendations for a general radiologist regarding choice of imaging sequences and reporting basic MRI examinations of the knee. We recommend using clinicians' terminology when it is applicable to the imaging findings, for example, when reporting meniscal, ligament and tendon, or cartilage pathology. The intent is to standardise reporting language and to make reports less equivocal. The aim of the paper is to improve the usefulness of the MRI report by understanding the strengths and limitations of the MRI exam with regard to clinical correlation. We hope the implementation of these recommendations into radiological practice will increase diagnostic accuracy and consistency by avoiding pitfalls and reducing overcalling of pathology on MRI of the knee. CLINICAL RELEVANCE STATEMENT: The recommendations presented here are meant to aid general radiologists in planning and assessing studies to evaluate acute and chronic knee findings by advocating the use of unequivocal terminology and discussing the strengths and limitations of MRI examination of the knee. KEY POINTS: • On MRI, the knee should be examined and assessed in three orthogonal imaging planes. • The basic general protocol must yield T2-weighted fluid-sensitive and T1-weighted images. • The radiological assessment should include evaluation of ligamentous structures, cartilage, bony structures and bone marrow, soft tissues, bursae, alignment, and incidental findings.

Subspecialisation in radiology in Europe, a survey of the accreditation council of imaging.

BACKGROUND: To provide an overview of existing Subspecialty Exams and Diplomas in Radiology and their endorsement as well as to providing an insight into the status of subspecialisation in radiology in Europe. The European Training Curriculum for Subspecialisation in Radiology mentions thirteen fields of subspecialisation within radiology. The websites of the corresponding subspecialty societies were checked for Subspecialty Exams and Diplomas. In addition, we performed a survey among European radiologists regarding subspecialisation in radiology. RESULTS: Ten out of 13 European subspecialty societies offer a European subspecialty diploma. At least 7 out of the 10 European subspecialties societies in radiology offering a European subspecialty diploma obtained European Society of Radiology (ESR) endorsement. Two out of 10 obtained European Union of Medical Specialists-Council of European Specialist Medical Assessment endorsement. Survey among European radiologists who were ESR full members in March 2021 demonstrated that almost 20% of respondents indicated that they have no subspecialisation. Another 15% indicated that their area of subspecialisation is not recognised in their country of work. Eighty-four percent of respondents would like their area of subspecialisation in radiology to be officially recognised. According to the respondents, the major benefit of having their subspecialisation in radiology officially recognised is personal interest (45%). CONCLUSIONS: There is a desire for more subspecialty recognition in radiology among European radiologists. Therefore, European subspecialty diplomas in radiology fulfil a need. Furthermore, there is room for further harmonisation and implementation on a European level regarding subspecialty training and recognition in radiology. CRITICAL RELEVANCE STATEMENT: As there is a desire for more subspecialty recognition in radiology among European radiologists, European subspecialty diplomas in radiology fulfil a need and there is still room for further harmonisation and implementation on a European level regarding subspecialty training in radiology. KEY POINTS: • Radiology has 13 subspecialties as per the European Training Curriculum for Subspecialisation. • Currently, 15 subspecialty diplomas are offered by European subspecialty societies in radiology • Members of the European Society of Radiology seek greater recognition of radiology subspecialties.

Sonoanatomy of the ilioinguinal, iliohypogastric, genitofemoral, obturator, and pudendal nerves: a practical guide for US-guided injections.

The ilioinguinal, iliohypogastric, genitofemoral, obturator, and pudendal nerves are the major sensory nerves that may be involved in chronic groin and genital pain with a significant impact on the quality of life of patients. The diagnosis remains clinical, and US-guided diagnostic injections using an anesthetic may aid in confirming the clinical suspicion. The anatomy of the peripheral nerves can be successfully studied using imaging. High-resolution ultrasound is increasingly used in the clinical setting for visualizing small peripheral nerves, and magnetic resonance imaging provides an anatomical overview of the relationship between small nerves and surrounding structures. In this pictorial assay, we review the anatomy and clinical relevance of the ilioinguinal, iliohypogastric, genitofemoral, obturator, and pudendal nerves. We summarize the various techniques for ultrasound identification, and present the ultrasound-guided infiltration techniques for injecting the ilioinguinal, iliohypogastric, genitofemoral, obturator, and pudendal nerves. Corresponding magnetic resonance images and clinical photos of the probe placement technique are provided for anatomical correlation. This paper is aimed to serve as a practical technical guide for physicians to familiarize themselves with the ultrasound anatomy of the major inguinal sensory nerves and to enable successful ultrasound identification and ultrasound-guided diagnostic or therapeutic infiltrations for pain management of the ilioinguinal, iliohypogastric, genitofemoral, obturator, and pudendal nerves.

Computed Tomography Assessment of Anatomic Graft Placement After ACL Reconstruction: A Comparative Study of Grid and Angle Measurements.

BACKGROUND: The anatomic placement of anterior cruciate ligament (ACL) grafts is often assessed with postoperative imaging. In clinical practice, graft angles are measured to indicate anatomic placement on magnetic resonance imaging, whereas grid measurements are performed on computed tomography (CT). Recently, a study indicated that graft angle measurements could also be assessed on CT. No consensus has yet been reached on which measurement method is best suited to assess anatomic graft placement. PURPOSE: To compare the ability of grid measurements and angle measurements to identify anatomic versus nonanatomic tunnel placement on CT performed in patients undergoing ACL reconstruction. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A total of 100 knees undergoing primary reconstruction with a hamstring graft (HAM group), 91 undergoing reconstruction with a bone-patellar tendon-bone graft (BPTB group), and 117 undergoing revision ACL reconstruction (REV group) were assessed with CT. Grid measurements of the femoral and tibial tunnels and angle measurements of grafts were performed. Graft placement, rated as anatomic or nonanatomic, was assessed with both methods. Pearson chi-square, analysis of variance, Kruskal-Wallis, and weighted kappa tests were performed as appropriate. RESULTS: The grid assessment classified 10% of the HAM group, 4% of the BPTB group, and 17% of the REV group as nonanatomic (P < .001). The angle assessment classified 37% of the HAM group, 54% of the BPTB group, and 47% of the REV group as nonanatomic. The weighted kappa between angle measurements and grid measurements was low in all groups (HAM: 0.009; BPTB: 0.065; REV: 0.041). CONCLUSION: The agreement between grid measurements and angle measurements was very low. The angle measurements seemed to overestimate nonanatomic tunnel placement. Grid measurements were better in identifying malpositioned grafts.

Breast cancers missed by screening radiologists can be detected by reading mammograms at a distance.

BACKGROUND: During locally organized quality assurance evaluation sessions for screening radiologists, we noticed that individual screening radiologists did miss tumours which in our opinion could be detected at a distance. AIM: To determine whether tumours missed by individual screening radiologists can be detected at a distance. METHODS: Twenty-eight screening mammograms of 28 females (mean age 63 years, range 49-73) with a pathologically proven malignant tumour missed by individual screening radiologists were mixed with 56 normal screening mammograms of 56 females (mean age 63 years, range 53-74). This test set was independently assessed by a senior screening radiologist and by a radiology resident without prior training in screening mammography at 1.5 m distance from the screen display. Readers were unaware of the prevalence of pathologically proven malignant tumours in the test set. Primary outcome was whether the reader would recall the woman. RESULTS: The senior screening radiologist recalled 28 of 28 women with a pathologically proven malignant tumour (sensitivity of 100%) and 16 of 56 women without pathology (specificity of 71%). The radiology resident recalled 25 of 28 women with a pathologically proven malignant tumour (sensitivity of 89%) and 10 of 56 women without pathology (specificity of 82%). CONCLUSION: Some malignant tumours missed by an individual screening radiologist can be detected from 1.5 m distance. Therefore, we recommend that screening radiologists consciously take a distant view before closely evaluating the mammogram in detail.

Protruding anterior medial meniscus-An indirect sign of posterior cruciate ligament deficiency.

BACKGROUND: to examine if PROTruding of the Anterior Medial Meniscus (PROTAMM) could be an indirect sign of PCL deficiency by comparing PROTAMM to passive posterior tibial sagging (PSS) for chronic PCL rupture on routine MRI. METHODS: Patients with PCL reconstruction between 2011 and 2016 were included in a case control study. Primarily cases with combined ACL/PCL injury were excluded. Secondary exclusion criteria were bony fractures, medial meniscus pathology and poor quality MRIs. Three (blinded) observers reviewed the pre-operative MRIs according to a pre-defined protocol. RESULTS: After applying the inclusion and primary exclusion criteria 16 patients were identified in the PCL rupture group. The control group consisted of 15 patients. After reviewing the MRIs, 6 were excluded due to secondary exclusion criteria. Mean PPS measured 4.8 mm (±â€¯4.4 mm) in the PCL rupture group and 1.8 mm (±2.9 mm) in the control group, p = 0.05. Mean PROTAMM was 3.6 mm (±0.6 mm) in the PCL rupture group and 0.7 mm (±0.9 mm) in the control group, p = 0.004. CONCLUSION: We found a mean PROTAMM of 3.6 mm in patients with PCL rupture. We suggest that this sign, after knee injury in an otherwise normal medial meniscus, is a promising indirect sign of PCL deficiency compared to PPS. Implementation of this sign in clinical practice may improve the sensitivity of routine non-weight bearing MRI in identifying PCL deficient knees.

The Anatomic Centers of the Femoral and Tibial Insertions of the Anterior Cruciate Ligament: A Systematic Review of Imaging and Cadaveric Studies Reporting Normal Center Locations.

BACKGROUND: The anterior cruciate ligament (ACL) is regularly reconstructed if knee joint function is impaired. Anatomic graft tunnel placement, often assessed with varying measurement methods, in the femur and tibia is considered important for an optimal clinical outcome. A consensus on the exact location of the femoral and tibial footprint centers is lacking. PURPOSE: To systematically review the literature regarding anatomic centers of the femoral and tibial ACL footprints and assess the mean, median, and percentiles of normal centers. STUDY DESIGN: Systematic review. METHODS: A systematic literature search was performed in the PubMed/Medline database in November 2015. Search terms were the following: "ACL" and "insertion anatomy" or "anatomic footprint" or "radiographic landmarks" or "quadrant methods" or "tunnel placement" or "cadaveric femoral" or "cadaveric tibial." English-language articles that reported the location of the ACL footprint according to the Bernard and Hertel grid in the femur and the Stäubli and Rauschning method in the tibia were included. Weighted means, weighted medians, and weighted 5th and 95th percentiles were calculated. RESULTS: The initial search yielded 1393 articles. After applying the inclusion and exclusion criteria, 16 studies with measurements on cadaveric specimens or a healthy population were reviewed. The weighted mean of the femoral insertion center based on measurements in 218 knees was 29% in the deep-shallow (DS) direction and 35% in the high-low (HL) direction. The weighted median was 26% for DS and 34% for HL. The weighted 5th and 95th percentiles for DS were 24% and 37%, respectively, and for HL were 28% and 43%, respectively. The weighted mean of the tibial insertion center in the anterior-posterior direction based on measurements in 300 knees was 42%, and the weighted median was 44%; the 5th and 95th percentiles were 39% and 46%, respectively. CONCLUSION: Our results show slight differences between the weighted means and medians in the femoral and tibial insertion centers. We recommend the use of the 5th and 95th percentiles when considering postoperative placement to be "in or out of the anatomic range."

Measurements of tunnel placements after anterior cruciate ligament reconstruction--A comparison between CT, radiographs and MRI.

BACKGROUND: A non-anatomic placement of the femoral and tibial tunnels may affect outcome in anterior cruciate ligament (ACL) reconstructions. Tunnel placements are validated with varying imaging modalities. We compared measurements of tunnel placements between radiographs, computed tomography (CT) and magnetic resonance imaging (MRI) in a clinical setting, assessed the reliability and aimed to decide on a possible "gold standard". METHODS: All patients who had undergone at least two of three modalities, radiographs, MRI and CT, after ACL reconstruction between January 2011 and June 2013 were included. Two radiologists measured tunnel placements according to a standardized protocol. Interobserver agreement was assessed with intraclass correlation coefficients (ICC), the intermodality differences with Bland-Atman plots. Radiation data for CT studies were collected. RESULTS: Forty-six CTs, 45 radiographs and 30 MRIs were reviewed. Femoral inter-observer agreement for radiographs was ICC=0.64, for CT ICC=0.86 and for MRI ICC = 0.75. Tibial inter-observer agreement for radiographs was ICC=0.92, for CT-mip ICC=0.91, for CT and MRI ICC = 0.87. No intermodality differences between the femoral measurements were observed. In the tibia, there were differences between radiographs and CT (-3.9%), radiographs-MRI (-3.6%), CT-CT mip (3.2%) and CTmip-MRI (-3.1%). The effective radiation doses varied between 0.025 and 0.045 mSv, mean and median was 0.033 mSv. CONCLUSION: There were differences in the tibial measurements between summation and single slice images. Only 3D-CT depicted the femoral tunnel in both directions. CT was consistently reliable in both femoral and tibial measurements. Effective radiation dose from CT was lower than previously reported. CT can safely be used in routine clinical practice to evaluate tunnel placements after ACL reconstruction.

Natural history and CT scan follow-up of subependymal giant cell tumors in tuberous sclerosis complex patients.

This study investigated whether subependymal giant cell tumors (SGCT) grow after the second decade in patients with tuberous sclerosis complex (TSC). In this retrospective longitudinal study all 214 TSC patients who had previously been in a single center cross-sectional study in 2007 were included. Institutional Review Board approval was obtained. In February 2012, the most recent contrast-enhanced CT scan of the brain since 2007 was reviewed for radiological signs of SGCT and, if present, the largest diameter was measured. The findings of the CT scans before 2007 were compared with the current findings. Of the 43 patients with radiological signs of SGCT in 2007 a follow-up CT scan was available for 34. Ten (29%) of these patients showed an increase in size of the SGCT. These 10 patients were on average 36 years old (median 34 years; range 26-50 years) and the average size of the SGCT was 17 mm (median 16 mm; range 11-29 mm), which corresponded to an average size increase of 5mm (median 4mm; range 2-8mm) after an average interval of 5 years (range 2-8 years). Of the 171 patients without radiological signs of SGCT in 2007 a follow-up CT scan was available for 138. Three (2%) of these patients showed radiological signs of SGCT on follow-up. These patients were 19, 23, and 41 years old and the SGCT was on average 13 mm (median 17 mm; range 4-19 mm). To conclude, in our cohort, CT scan demonstrated both growth of SGCT and development of new SGCT after the second decade of life in TSC patients.

A motive for the use of a posterior approach in shoulder arthography: ventral leakage of contrast medium.

BACKGROUND: Some orthopedic surgeons request a posterior approach for shoulder magnetic resonance (MR) arthrography, especially in patients with anterior shoulder instability, to avoid interpretive difficulties in differentiating anterior extraarticular contrast injection when using an anterior approach from ventral leakage of contrast. PURPOSE: To determine the occurrence of ventral leakage of contrast in shoulder MR arthrography when using a posterior approach. MATERIAL AND METHODS: Retrospectively, we included 73 consecutive patients who underwent shoulder MR arthrography (1.0 Tesla) using the posterior approach. Three unsuccessful procedures were excluded. Ventral leakage of contrast, defined as contrast seen around the musculus subscapularis without distention of the posterior capsule, was recorded. Descriptive statistics were used. RESULTS: Seventy shoulders were included. Forty-one left shoulders were involved (59%). Mean age of patients was 49 years (range, 17-76 years). Thirty-five patients were women (50%). Ventral leakage of contrast was seen in 12 shoulders (17%). CONCLUSION: As ventral leakage of contrast was seen in a substantial number of cases when using a posterior approach in shoulder MR arthrography, the use of a posterior approach is advised to avoid misinterpretation of ventral contrast leakage with accidental extra articular contrast injection, and to increase confidence in the final radiological diagnosis.

Intraosseous venous drainage of pretibial varices.

In this study, we present the case of a 74-year-old male patient who presented with a painful pretibial swelling. The patient had a history of varices of the ipsilateral leg for which he had undergone stripping and ligation. At physical examination, pretibial varices and an associated soft tissue swelling were found. Ultrasound revealed pretibial varices, one of which caused a defect on the anterior tibial cortex. Plain radiography showed a small subcortical lucency of the tibial shaft. MRI confirmed the presence of pretibial varices, one of which perforated through the anterior tibial cortex and then coursed intramedullary as an enlarged intraosseous vein. Based on these findings, the diagnosis of varices with an intraosseous venous drainage anomaly was made. The patient was subsequently successfully treated by ambulatory minisurgical phlebectomy. Knowledge and recognition of this intraosseous venous drainage anomaly, which is a rare condition, is pivotal for correct patient management. We review clinical and imaging findings, and discuss previously reported cases.

Normal anatomical variants of the labrum of the hip at magnetic resonance imaging: a systematic review.

OBJECTIVE: To review the literature regarding normal labral variants at MRI. METHODS: A systematic search was performed in PubMed/MEDLINE and Embase. For each included study, information regarding normal labral variants and findings in asymptomatic subjects was extracted. RESULTS: There were 24 studies in symptomatic patients, evaluating 822 hips. The presence of a sublabral sulcus was reported by four studies in 41 hips (5 % of all evaluated hips), occurring at all anatomical locations. There were 3 cadaver studies, investigating 32 hips and reporting no normal labral variants. There were 8 studies in asymptomatic subjects, evaluating 1,096 hips. Labral tears were reported in 213 hips (19 %); no sublabral sulci were reported. Labral shape was most commonly triangular (59-89 %), whereas rounded (11-16 %), flattened (13-37 %) and teardrop (41 %) shapes were less frequently seen. Overall methodological quality of included studies was moderate, with median total quality scores of 43 % (symptomatic patients), 71 % (cadavers) and 70 % (asymptomatic subjects). CONCLUSION: At MRI, a sublabral sulcus can be found at any anatomical location. Our results suggest that its prevalence is at least 5 % in symptomatic patients. The most common labral shape is triangular. Rounded, flattened and teardrop shapes are less frequent but are also encountered in asymptomatic subjects. KEY POINTS: • A sublabral sulcus can be detected by MRI at any anatomical site • Its prevalence is estimated to be at least 5 % in symptomatic patients • The most common shape of the hip labrum is triangular • Rounded, flattened and teardrop shapes are less frequent.

Mature fat cells in the myocardium of patients with tuberous sclerosis complex.

AIM: Routine abdominal CT scans in patients with tuberous sclerosis complex (TSC) showed characteristic fatty foci in the depicted caudal portions of the myocardium. The purpose of this study was to investigate if areas of abnormal myocardium in patients with TSC could also be found in post-mortem specimens. METHODS: A retrospective search of our histopathology database was performed to identify specimens of the heart of patients with TSC. Institutional review board approval was obtained, and patient informed consent was waived. Four specimens were included (mean age, 44 years; range 32-68 years; 2 females). RESULTS: Two specimens (50%) of the heart showed areas of mature fat cells in the myocardium, without associated inflammation, without associated fibrosis, without entrapped myocardial cells and without a capsule. CONCLUSION: Post-mortem specimens of the heart of patients with TSC showed areas of mature fat cells in the myocardium which seem to be unique for TSC.

Focal fatty areas in the myocardium of patients with tuberous sclerosis complex: a unique finding.

With this collection of computed tomography and magnetic resonance images, we illustrate a recently described novel finding in the myocardium of patients with tuberous sclerosis complex.

Echocardiographic screening results in patients with tuberous sclerosis complex.

We sought to examine the frequency of abnormal echocardiographic findings in patients with tuberous sclerosis complex. In a retrospective cohort study, we included all patients with known tuberous sclerosis complex who had been sent to our cardiology department for echocardiographic screening from 1995 through August 2003 (n=56). Two research scientists independently reviewed the reports of the echocardiographic screening examinations for abnormal findings. We used descriptive statistics, the Mann-Whitney U test, and the chi(2) test. The mean age of patients included in the study was 35 years (range, 12-73 yr); 23 patients were male. Abnormal findings were seen in 22 patients (39%). The most common abnormal findings were focal areas of increased intramyocardial echogenicity, which were seen in 16 patients (29%). The clinical consequence of this finding is still unknown. We conclude that echocardiographic abnormalities are common in patients with tuberous sclerosis complex.

Fatty foci in the myocardium in patients with tuberous sclerosis complex: common finding at CT.

PURPOSE: To examine the morphologic characteristics of focal fatty foci in the myocardium of patients with tuberous sclerosis complex (TSC) at computed tomography (CT). MATERIALS AND METHODS: Institutional review board approval was obtained, and patient informed consent was waived. Fifty-five patients with TSC (mean age, 37 years; range, 16-67 years; 22 male patients) who had CT results available that included at least the basal portions of the heart were included. Fifty-five age- and sex-matched control subjects without TSC were selected from a CT database. Images were reviewed for the presence of areas of fat attenuation in the depicted portions of the myocardium. Descriptive statistics and the McNemar test for case-control comparisons were used. RESULTS: CT results demonstrated foci of fat attenuation within the myocardium in 35 (64%) of 55 patients with TSC. Foci were well circumscribed and focal and located in the interventricular septum, left ventricle wall, right ventricle wall, and papillary muscles. Size varied between 3 x 1 mm and 62 x 31 mm. Multiple lesions were seen in 19 patients. In the control group, only one (2%) lesion with fat attenuation was found (P < .001). Its linear shape and subendocardial location in the left ventricular wall differed from the morphology of fatty foci seen in patients with TSC. CONCLUSION: Despite incomplete depiction of the heart with CT, the majority of patients with TSC demonstrated well-circumscribed foci of fat attenuation in the myocardium that were not present in age- and sex-matched control subjects. This suggests that such fatty foci may be another characteristic of TSC.

DSA versus multi-detector row CT angiography in peripheral arterial disease: randomized controlled trial.

PURPOSE: To prospectively compare therapeutic confidence in, patient outcomes (in terms of quality of life) after, and the costs of digital subtraction angiography (DSA) with those of multi-detector row computed tomographic (CT) angiography as the initial diagnostic imaging test in patients with peripheral arterial disease (PAD). MATERIALS AND METHODS: Institutional medical ethics committee approval and patient informed consent were obtained. Between April 2000 and August 2001, patients with PAD were randomly assigned to undergo either DSA or multi-detector row CT angiography as the initial diagnostic imaging test. Outcomes were the therapeutic confidence assessed by physicians (on a scale from 0 to 10), the need for additional imaging, the health-related quality of life at 6-month follow-up, diagnostic and therapeutic costs, and the costs for a hospital stay. Costs were computed from a hospital perspective according to Dutch guidelines for cost calculations in health care. Mean outcomes were compared between groups with unpaired t testing and were adjusted for predictive baseline characteristics with multivariable regression analysis. RESULTS: Among the 145 patients, 72 were randomly allocated to the DSA group and 73 to the CT angiography group. One patient in the DSA group had to be excluded. Mean age was 63 years in the DSA group and 64 years in the CT angiography group. There were 47 men in the DSA group and 58 men in the CT angiography group. Physician confidence in making a correct therapeutic choice was significantly higher at DSA (mean confidence score, 8.2) than at CT angiography (mean score, 7.2; P < .001). During 6-month follow-up, 14% less additional imaging was performed in the DSA group than in the CT angiography group (P = .3). No significant quality-of-life differences were found between groups. The diagnostic cost associated with DSA (564 +/- 210 euro [standard deviation]) was significantly higher than that associated with CT angiography (363 +/- 273 euro), a difference of -201 euro (95% confidence interval: -281 euro, -120 euro; P < .001). Therapeutic and hospitalization costs were similar for both strategies. CONCLUSION: These results suggest that use of noninvasive multi-detector row CT angiography instead of DSA as the initial diagnostic imaging test for PAD provides sufficient information for therapeutic decision making and reduces imaging costs.

Peripheral arterial disease: therapeutic confidence of CT versus digital subtraction angiography and effects on additional imaging recommendations.

PURPOSE: To compare multi-detector row computed tomographic (CT) angiography and digital subtraction angiography (DSA) prior to revascularization in patients with symptomatic peripheral arterial disease for the purpose of assessing recommendations for additional imaging and physician confidence ratings for chosen therapy. MATERIALS AND METHODS: In a randomized controlled trial, 73 patients were assigned to CT angiography, and 72 were assigned to DSA. Physician confidence in the treatment decision was measured as a continuous outcome on a scale of 0-10 (uncertain to certain) and as a dichotomous outcome (further imaging recommended, yes or no). Mean confidence scores and additional imaging recommendations were compared between CT and DSA groups in an intention-to-diagnose-and-treat analysis. To detect trends in confidence, confidence scores were plotted over time, and multiple linear regression analysis was performed. To detect trends in additional imaging recommendations, logistic regression analysis was used. Data from eligible nonrandomized patients were analyzed separately. RESULTS: No statistically significant difference in baseline characteristics between randomized groups was found. CT had a lower confidence score than did DSA (7.2 vs 8.2, P < .001). Further imaging was recommended more often after CT (25 of 71 patients, 35%) than after DSA (nine of 66 patients, 14%; P = .003). Analysis of trends demonstrated increasing (but not statistically significant) confidence in CT and stable confidence in DSA. No significant difference was found in baseline characteristics between randomized and nonrandomized patients. Among nonrandomized patients, no significant difference in mean confidence score (8.2 vs 8.3, P = .26) was found between CT (n = 24) and DSA (n = 26). CONCLUSION: With CT angiography, physician confidence decreases with an associated increase in additional imaging prior to revascularization in patients with symptomatic peripheral arterial disease. Given that CT is less invasive than DSA, results suggest that CT may replace DSA in selected cases.

Abdominal aortic aneurysms: cost-effectiveness of elective endovascular and open surgical repair.

PURPOSE: To evaluate the cost-effectiveness of elective endovascular and open surgical repair of infrarenal abdominal aortic aneurysms (AAAs) by taking into account short- and long-term outcomes. MATERIALS AND METHODS: A Markov decision model was developed to evaluate quality-adjusted life-years (QALYs) and lifetime costs of endovascular and open surgical repair. The incremental cost-effectiveness ratio (CER) was calculated for endovascular repair relative to open surgery in a cohort of 70-year-old men with an AAA between 5 and 6 cm in diameter. Clinically effectiveness data were derived from the literature. Cost data were derived from Medicare reimbursement rates, the hospital database, and the literature. One- and multiple-way sensitivity analyses were performed on uncertain model parameters. Costs were converted to year 2000 U.S. dollars; future costs and outcomes were discounted at 3%. RESULTS: The incremental CER of endovascular repair was 9,905 dollars per QALY. QALYs and lifetime costs were higher for endovascular repair than for open surgery (6.74 vs 6.52 and 39,785 dollars vs 37,606 dollars, respectively). In sensitivity analyses, the incremental CER was insensitive to immediate conversion rate and procedure mortality rate. The incremental CER was sensitive (ie, more than 75,000 dollars per QALY or endovascular repair was ruled out by dominance) to systemic-remote complications, long-term failures, and ruptures. CONCLUSION: The results suggest that endovascular repair is a cost-effective alternative compared with open surgery for the elective repair of AAA. The benefits and cost-effectiveness are highly dependent on uncertain outcomes, however, particularly long-term failure and rupture rates.