Reducing Seroma Formation and Its Sequelae After Mastectomy by Closure of the Dead Space: A Multi-center, Double-Blind Randomized Controlled Trial (SAM-Trial).

BACKGROUND: Seroma is a common complication after mastectomy, with an incidence of 3% to 85%. Seroma is associated with pain, delayed wound healing, and additional outpatient clinic visits, leading potentially to repeated seroma aspiration or even surgical interventions. This study aimed to assess the effect of flap fixation using sutures or tissue glue in preventing seroma formation and its sequelae. METHODS: Between June 2014 and July 2018, 339 patients with an indication for mastectomy or modified radical mastectomy were enrolled in this randomized controlled trial in the Netherlands. Patients were randomly allocated to one of the three following arms: conventional wound closure (CON, n = 115), flap fixation using sutures (FFS, n = 111) or flap fixation using tissue glue (FFG, n = 113). The primary outcome was the need for seroma aspiration. The secondary outcomes were additional outpatient department visits, surgical-site infection, shoulder function and mobility, cosmesis, skin-dimpling, and postoperative pain scores. RESULTS: Flap fixation after mastectomy leads to fewer seroma aspirations than conventional wound closure (CON 17.5% vs FFS 7.3% vs FFG 10.8%; p = 0.057), with a significant difference between flap fixation with sutures and conventional wound closure (odds ratio [OR], 0.37; 95% confidence interval [CI], 0.16-0.89; p = 0.025). Flap fixation has no significant negative effect on surgical-site infections, shoulder function and mobility, cosmesis, skin-dimpling, or postoperative pain. CONCLUSION: Flap fixation using sutures leads to a significant reduction in aspirations of post-mastectomy seromas. The authors strongly advise surgeons to use sutures for flap fixation in patients undergoing mastectomy. (ClinicalTrials.gov no. NCT03305757). PREREGISTRATION: The trial was registered after enrollment of the first participant. However, no specific explanation exists for this except that through the years more importance has been given to central trial registration. Our research team can ensure that after enrollment of the first participant, no changes were made to the trial, analysis plan, and/or study design.

Comparing population and incident data for optimal air ambulance base locations in Norway.

BACKGROUND: Helicopter emergency medical services are important in many health care systems. Norway has a nationwide physician manned air ambulance service servicing a country with large geographical variations in population density and incident frequencies. The aim of the study was to compare optimal air ambulance base locations using both population and incident data. METHODS: We used municipality population and incident data for Norway from 2015. The 428 municipalities had a median (5-95 percentile) of 4675 (940-36,264) inhabitants and 10 (2-38) incidents. Optimal helicopter base locations were estimated using the Maximal Covering Location Problem (MCLP) optimization model, exploring the number and location of bases needed to cover various fractions of the population for time thresholds 30 and 45 min, in green field scenarios and conditioned on the existing base structure. RESULTS: The existing bases covered 96.90% of the population and 91.86% of the incidents for time threshold 45 min. Correlation between municipality population and incident frequencies was -0.0027, and optimal base locations varied markedly between the two data types, particularly when lowering the target time. The optimal solution using population density data put focus on the greater Oslo area, where one third of Norwegians live, while using incident data put focus on low population high incident areas, such as northern Norway and winter sport resorts. CONCLUSION: Using population density data as a proxy for incident frequency is not recommended, as the two data types lead to different optimal base locations. Lowering the target time increases the sensitivity to choice of data.

Exploring optimal air ambulance base locations in Norway using advanced mathematical modelling.

BACKGROUND: Helicopter emergency medical services are an important part of many healthcare systems. Norway has a nationwide physician staffed air ambulance service with 12 bases servicing a country with large geographical variations in population density. The aim of the study was to estimate optimal air ambulance base locations. METHODS: We used high resolution population data for Norway from 2015, dividing Norway into >300 000 1 km×1 km cells. Inhabited cells had a median (5-95 percentile) of 13 (1-391) inhabitants. Optimal helicopter base locations were estimated using the maximal covering location problem facility location optimisation model, exploring the number of bases needed to cover various fractions of the population for time thresholds 30 and 45 min, both in green field scenarios and conditioning on the current base structure. We reanalysed on municipality level data to explore the potential information loss using coarser population data. RESULTS: For a 45 min threshold, 90% of the population could be covered using four bases, and 100% using nine bases. Given the existing bases, the calculations imply the need for two more bases to achieve full coverage. Decreasing the threshold to 30 min approximately doubles the number of bases needed. Results using municipality level data were remarkably similar to those using fine grid information. CONCLUSIONS: The whole population could be reached in 45 min or less using nine optimally placed bases. The current base structure could be improved by moving or adding one or two select bases. Municipality level data appears sufficient for proper analysis.

[Social Security Needs Social Medicine: Self-image of Physicians Practicing Social Medicine in Statutory Health Insurances and Social Security Systems]. / Soziale Sicherheit braucht Sozialmedizin Selbstverständnis von Ärztinnen und Ärzten in der sozialmedizinischen Begutachtung und Beratung.

OBJECTIVE: In January, 2014, the division "Social Medicine in Practice and Rehabilitation" of the German Society for Social Medicine and Prevention established a working group on the self-image of the physicians active in the field of social medicine (medical expertise and counseling). METHODS: The result of this work is the contribution presented here after consensus was achieved by specialists of social medicine from different fields and institutions (social security etc.) and in good cooperation with Prof. Dr. Gostomzyk and Prof. Dr. Robra. RESULTS: Based on the importance of an up to date social medicine for claimants and recipients of benefits on the one hand and the social security system on the other, and also on a description of the subjects, objectives and methods the following aspects are presented: · The perspective of social medicine. · Qualification in social medicine, concerning specialist training and continuing medical education. · The fields of duty of experts in social medicine. · The proceedings in social medicine. The working group identified challenges for the specialists in social medicine by a narrowed perception of social medicine by physicians in hospitals and practice, accompanied by an enlarged importance of expertise in social medicine, by the demand for more "patient orientation" and gain of transparency, and concerning the scientific foundation of social medicine. CONCLUSIONS: The working group postulates: · The perspective of social medicine should be spread more widely.. · Confidence in experts of social medicine and their independency should be strengthened.. · The not case-related consulting of the staff and executives should be expanded.. · Social medicine in practice needs support by politics and society, and especially by research and teaching.. · Good cooperation and transfer of experiences of the different branches of social security are essential for the impact of social medicine..

[Consistency and Reliability of MDK Expertise Examining the Encoding in the German DRG System]. / Einheitlichkeit der richtlinienkonformen Begutachtung durch den Medizinischen Dienst der Krankenversicherung bei der Prüfung der Kodierung im G-DRG-System.

INTRODUCTION: Hospital inpatient stays are reimbursed on the basis of German diagnosis-related groups (G-DRG). The G-DRG classification system is based on complex coding guidelines. The Medical Review Board of the Statutory Health Insurance Funds (MDK) examines the encoding by hospitals and delivers individual expertises on behalf of the German statutory health insurance companies in cases in which irregularities are suspected. A study was conducted on the inter-rater reliability of the MDK expertises regarding the scope of the assessment. METHODS: A representative sample of 212 MDK expertises was taken from a selected pool of 1 392 MDK expertises in May 2013. This representative sample underwent a double-examination by 2 independent MDK experts using a special software based on the 3MTM G-DRG Grouper 2013 of 3M Medica, Germany. The following items encoded by the hospitals were examined: DRG, principal diagnosis, secondary diagnoses, procedures and additional payments. It was analysed whether the results of MDK expertises were consistent, reliable and correct. RESULTS: 202 expertises were eligible for evaluation, containing a total of 254 questions regarding one or more of the 5 items encoded by hospitals. The double-examination by 2 independent MDK experts showed matching results in 187 questions (73.6%) meaning they had been examined consistently and correctly. 59 questions (23.2%) did not show matching results, nevertheless they had been examined correctly regarding the scope of the assessment. None of the principal diagnoses was significantly affected by inconsistent or wrong judgment. CONCLUSION: A representative sample of MDK expertises examining the DRG encoding by hospitals showed a very high percentage of correct examination by the MDK experts. Identical MDK expertises cannot be achieved in all cases due to the scope of the assessment. Further improvement and simplification of codes and coding guidelines are required to reduce the scope of assessment with regard to correct DRG encoding and its examination.

A niobium water target for routine production of [¹8F]Fluoride with a MC 17 cyclotron.

A [(18)F]Fluoride water target was constructed for a Scanditronix MC 17 cyclotron, without a beam line, with a typical wide beam of ∼30 × 5 mm(2). Niobium was used as target chamber material. One hour irradiation with 45µA protons yields about 110 GBq [(18)F]Fluoride. The saturation yield is 8.0 ± 0.6 GBq/µA (EOB). The FDG yield is 60 ± 5% (EOS) with a TracerLab MX (G.E. Healthcare). More than 100 GBq FDG is routinely produced after a 2h irradiation.

Decision support system for the operating room rescheduling problem.

Due to surgery duration variability and arrivals of emergency surgeries, the planned Operating Room (OR) schedule is disrupted throughout the day which may lead to a change in the start time of the elective surgeries. These changes may result in undesirable situations for patients, wards or other involved departments, and therefore, the OR schedule has to be adjusted. In this paper, we develop a decision support system (DSS) which assists the OR manager in this decision by providing the three best adjusted OR schedules. The system considers the preferences of all involved stakeholders and only evaluates the OR schedules that satisfy the imposed resource constraints. The decision rules used for this system are based on a thorough analysis of the OR rescheduling problem. We model this problem as an Integer Linear Program (ILP) which objective is to minimize the deviation from the preferences of the considered stakeholders. By applying this ILP to instances from practice, we determined that the given preferences mainly lead to (i) shifting a surgery and (ii) scheduling a break between two surgeries. By using these changes in the DSS, the performed simulation study shows that less surgeries are canceled and patients and wards are more satisfied, but also that the perceived workload of several departments increases to compensate this. The system can also be used to judge the acceptability of a proposed initial OR schedule.

[Metastatic apocrine adenocarcinoma of the penis: cytostatic therapy]. / Metastasiertes apokrines Adenokarzinom des Penis: zytostatische Therapie.

Metastatic carcinoma of the genital apocrine sweat glands is a rare clinical entity. A cytostatic treatment with MTX and bleomycin was performed empirically but did not show any satisfactory efficacy. The conversion of the chemotherapeutic regime to a tyrosine kinase inhibitor (sunitinib) showed a morphologically visible and clinically proven success in terms of a significant slowing down of the previous rapid progression of the disease.

[Random sampling according to section 17 c KHG--report on the experience of maximal care hospitals in Hesse]. / Die Stichprobenprüfung nach 17 c KHG--Erfahrungsbericht aus Krankenhäusern der Maximalversorgung in Hessen.

Hospital billing converted to "German diagnosis-related groups" (G-DRG) for in-patient treatment in Germany is reviewed, except in psychiatry where per-diems are still in use. Currently thousands of bills are sent to the Medical Service for scrutiny. In addition, the law relating to Hospital Financing (Krankenhausfinanzierungsgesetz, para. 17 c) provides for systematic checks on a random sample of bills from a given hospital. The Medical Service of the Social Security Health Insurance reports on the experience in the State of Hessen. Present regulations exclude from the random sample those bills that have already been presented for a check on a case by case basis. Excluding these cases from the random sample introduces a bias in an avoidable way. The present rule is contrary to valid conclusions from the random sampling and should be abolished.

[Challenges in social medicine counseling and expert assessment]. / Herausforderungen der sozialmedizinischen Beratung und Begutachtung.

The services of expert testimony and professional consultation in sociomedicine are considerably challenged. It is not so much the question of maintaining their traditional functions but of developing them in order to maintain at least the status quo. These challenges consist for example of the lack of a scientific basis for the complex function of allocation, piloting and control of medical resources. Some new approaches are offered by the ICIDH, by new instruments of medical assessment and by quality management including "evidence-based medicine". Furthermore the services of expert testimony must bridge the gap between patients and social services in a way which is satisfactory for the population. Nevertheless, these services must maintain strict independence.

[How many intensive care beds are necessary? A quantitative study with the Therapeutic Intervention Scoring System (TISS) in 5 Hessian hospitals)]. / Wie viele Intensivbetten sind notwendig? Eine quantitative Untersuchung mit dem Therapeutic Intervention Scoring System (TISS) in fünf hessischen Krankenhäusern.

In five major Hessian hospitals all patients of critical care units have been grouped according to the Therapeutic Intervention Scoring System (TISS) over a time span of four weeks. The objective was to establish the critical care patient capacity needed in accordance with the Hessian Guidelines for Critical Care. Sample surveys showed that the ascertained data are highly reliable. 10,756 TISS-classifications have been evaluated in total. 9.4% of the classifications have been assigned to general ward, 27.5% to intensive monitoring and 63.1% to intensive treatment. Assuming a standard rate of use of 85% over the year this revealed an average requirement of critical care patient capacity of 6.1% of the total number of beds. The results of the investigation were readily accepted by health insurances and hospitals involved.

Endovascular repair of an extracranial internal carotid artery aneurysm complicated by heparin-induced thrombocytopenia and thrombosis.

PURPOSE: To report the endovascular treatment of a symptomatic extracranial internal carotid artery (ICA) aneurysm that was complicated by heparin-induced thrombocytopenia and thrombosis. METHODS AND RESULTS: After undergoing a coronary artery bypass graft procedure, a patient was diagnosed with a symptomatic, 3.5-cm ICA aneurysm by computed tomography and angiography. Via a semiclosed access, an Enduring vascular graft was inserted under controlled back bleeding from the ICA. The patient was recovering uneventfully when routine duplex scanning on the fifth postoperative day suggested multiple thrombi within the graft, which was confirmed by arteriography. Thrombectomy and local fibrinolysis were performed; however, the graft occluded the next day without causing neurological symptoms. Heparin-induced thrombocytopenia was diagnosed by enzyme-linked immunosorbent assay. CONCLUSIONS: Endovascular repair of high cervical extracranial ICA aneurysms is feasible, and protection against intracerebral embolization can be achieved using a semiclosed technique with controlled back bleeding from the ICA during endograft deployment. However, multiple thrombi or thrombotic occlusion during the postoperative period, particularly in a patient already sensitized to heparin, should direct attention toward possible heparin-induced thrombocytopenia.

Three-dimensional intravascular ultrasound assessment of abdominal aortic aneurysm necks.

PURPOSE: To document the accuracy of an automated analysis system for measuring lumen diameter and neck lengths of abdominal aortic aneurysms (AAAs) from intravascular ultrasound (IVUS) images and to describe additional features associated with 3-dimensional (3D) IVUS imaging. METHODS: Twenty-two aortic aneurysms were studied with IVUS. Lumen diameters obtained using the automated analysis system were compared with manual measurements from axial IVUS scans, as were neck lengths obtained using automated analysis versus those measured with the aid of a displacement sensing device. Automated analyses were repeated by a second observer. Agreement was expressed as the coefficient of variation (CV). RESULTS: Twenty proximal aortic, 6 distal aortic, and 3 iliac necks were available for analysis. Comparison between automated analysis and manual measurements for lumen diameter revealed a difference of 0.45 +/- 0.42 mm (mean +/- SD, Pearson's r = 0.99, p < 0.001, CV = 2.1%) and a difference of 0.05 +/- 0.12 cm (r = 0.99, p = 0.04, CV = 4.1%) for neck length. Interobserver difference for lumen diameter was 0.13 +/- 0.66 mm (r = 0.99, p < 0.001, CV = 3.4%) and 0.05 +/- 0.11 cm for length measurements (r = 0.99, p = 0.02, CV = 3.5%). The 3D IVUS imaging facilitated the identification of neck configuration. CONCLUSIONS: Automated analysis of IVUS images allows accurate measurement of the lumen diameter of proximal and distal AAA necks and gives length measurements comparable to those of manual analysis. Longitudinal display of IVUS images aids in the elucidation of neck anatomy.

Reproducibility of volumetric quantification in intravascular ultrasound images.

The reproducibility of volume measurements in intravascular ultrasound (IVUS) images derived from separate pull-back manoeuvres remains to be elucidated. Patients (n = 23) were imaged with IVUS prior to (first series) and following percutaneous transluminal angioplasty (PTA) (second series). In 15 patients, one matched vascular segment (3-4 cm in length), not subjected to PTA, was used for analysis of lumen, vessel and plaque volume using an automated contour analysis system. Volume measurements assessed by two independent observers and in the two separate series were compared. Interobserver differences in volume measurements were small (< or =0.4%), with low coefficients of variation (< or =1.7%) and high correlation coefficients (r = 1.00). Differences in volume measurements obtained in the two separate series were small (< or =2.6%), with low coefficients of variation (< or = 8.6%) and high correlation coefficients (r = 0.97-0.99). In conclusion, volume measurements derived from IVUS images are highly reproducible. Therefore, IVUS may be used to monitor the progression/regression of atherosclerotic plaque volume in a longitudinal study.

Intravascular ultrasound evidence for coarctation causing symptomatic renal artery stenosis.

BACKGROUND: A recent study of human cadaveric renal arteries revealed that renal artery narrowing could be due not only to atherosclerotic plaque compensated for by adaptive remodeling, but also to hitherto undescribed focal narrowing of an otherwise normal renal arterial wall (ie, coarctation). The present study investigated whether vessel coarctation could be identified in patients with symptomatic renal artery stenosis (RAS). METHODS AND RESULTS: Consecutive symptomatic patients with angiographically proven atherosclerotic RAS who were referred for stent placement were studied by 30-MHz intravascular ultrasound before intervention (n=18) or after predilatation (n=18). Analysis included assessment of the media-bounded area and plaque area (PLA) at the most stenotic site and at a distal reference site (most distal cross-section in the main renal artery with normal appearance). Coarctation was considered present whenever the target/reference media-bounded area was

Accurate assessment of abdominal aortic aneurysm with intravascular ultrasound scanning: validation with computed tomographic angiography.

PURPOSE: The purpose of this study was to assess the accuracy of intravascular ultrasound (IVUS) parameters of abdominal aortic aneurysm, used for endovascular grafting, in comparison with computed tomographic angiography (CTA). METHODS: This study was designed as a descriptive study. Between March 1997 and March 1998, 16 patients with abdominal aortic aneurysms were studied with angiography, IVUS (12.5 MHz), and CTA. The length of the aneurysm and the length and lumen diameter of the proximal and distal neck obtained with IVUS were compared with the data obtained with CTA. The measurements with IVUS were repeated by a second observer to assess the reproducibility. Tomographic IVUS images were reconstructed into a longitudinal format. RESULTS: IVUS results identified 31 of 32 renal arteries and four of five accessory renal arteries. A comparison of the length measurements of the aneurysm and the proximal and distal neck obtained with IVUS and CTA revealed a correlation of 0.99 (P <.001), with a coefficient of variation of 9%. IVUS results tended to underestimate the length as compared with the CTA results (0.48 +/- 0.52 cm; P <.001). A comparison of the lumen diameter measurements of the proximal and distal neck derived from IVUS and CTA showed a correlation of 0.93 (P <.001), with a coefficient of variation of 9%. IVUS results tended to underestimate aneurysm neck diameter as compared with CTA results (0.68 +/- 1.76 mm; P =.006). Interobserver agreement of IVUS length and diameter measurements showed a good correlation (r = 1.0; P <.001), with coefficients of variation of 3% and 2%, respectively, and no significant differences (0.0 +/- 0.16 cm and 0.06 +/- 0.36 mm, respectively). The longitudinal IVUS images displayed the important vascular structures and improved the spatial insight in aneurysmal anatomy. CONCLUSION: Intravascular ultrasound scanning results provided accurate and reproducible measurements of abdominal aortic aneurysm. The longitudinal reconstruction of IVUS images provided additional knowledge on the anatomy of the aneurysm and its proximal and distal neck.

Validation of automated contour analysis of intravascular ultrasound images after vascular intervention.

PURPOSE: The purpose of this study was to determine the feasibility of automated contour analysis of intravascular ultrasound images obtained after vascular intervention. STUDY DESIGN: This was a descriptive study. METHODS: Intravascular ultrasound images obtained from patients after balloon angioplasty (n = 10), stent (n = 10), or stent graft placement (n = 10) were analyzed. A comparison was made between lumen area measured with an automated and a manual system. The location showing the smallest lumen area derived from the automated system was compared with the smallest lumen area selected by visual estimation. RESULTS: Images containing a dissection as a result of balloon angioplasty could not be analyzed by the automated system. The coefficient of variation between the lumen area measurements obtained with the automated system and the manual tracing system of images with a stent (n = 76) or stent graft (n = 79) was 2.7% and 2.1%, respectively. Correlation between the two systems was high (r = 1.00, p < 0.01) both for images containing stents or stent grafts. Minimum lumen area measured with the automated analysis system was smaller than minimum lumen area selected by visual estimation (mean difference 0.8 mm2 (4.9%) for stents and 2.4 mm2 (10.9%) for stent grafts). The location of the smallest lumen area determined with both systems was the same (<1 cm) in 16 cases and differed more than 1 cm in 4 other cases. CONCLUSIONS: The automated analysis system shows good agreement with manual contour analysis of lumen area in images with a stent or stent graft and is a reliable tool for determination of the smallest lumen area. The system is not able to analyze an irregular-shaped lumen area caused by a dissection.

Reliability and reproducibility of automated contour analysis in intravascular ultrasound images of femoropopliteal arteries.

An automated contour analysis system was previously developed to increase reproducibility and facilitate quantitative analyses of intravascular ultrasound (IVUS) images. The aim of this study was to compare measurements by this automated system with those obtained by conventional manual tracing, and to determine the intra- and interobserver variability of the automated system. IVUS images obtained in the femoropopliteal artery (n = 12) were analyzed with both systems. Area measurements by the automated system agreed well with the results obtained by manual tracing, displaying low coefficients of variation (8.5 to 15.7%) and high correlation coefficients (r = 0.92 to 0.98). Intra- and interobserver comparison of lumen area, vessel area, plaque area and percentage area stenosis showed low coefficients of variation (6.0 to 15.3% and 5.7 to 14.0%, respectively) and high correlation coefficients (both: r = 0.93 to 0.99). These data indicate that the automated analysis system is a reliable tool for the quantitative assessment of vessel dimensions in IVUS images obtained during clinical examination of peripheral arteries.

Intravascular ultrasonography allows accurate assessment of abdominal aortic aneurysm: an in vitro validation study.

OBJECTIVE: The objective of this study was to acquire insight into the interpretation of intravascular ultrasound images of the abdominal aorta and to assess to what extent this technique can provide useful parameters for the endovascular treatment of patients with abdominal aortic aneurysm. STUDY DESIGN: This was a descriptive study. METHODS: Fifteen abdominal aortic specimens (normal, atherosclerotic, or aneurysmal) were studied. Ultrasonic images and corresponding histologic sections were compared for vessel wall characteristics, lesion morphologic characteristics, and lumen diameter. The length of the aneurysm and the length of the proximal and distal neck were measured and compared with external measurements. Tomographic images were reconstructed to a three-dimensional format. RESULTS: Normal aortic wall was seen as a two- or three-layered structure corresponding with intima, media, and adventitia. A distinction could be made among fibrous lesion, calcified lesion, and thrombus and between normal and aneurysmal aorta. Correlation between the histologic specimens and intravascular ultrasonography for lumen diameter measurements was high (r = 0.93; p < 0.001). In a similar fashion, correlation between external measurements and intravascular ultrasound measurements on the length of the aneurysm and its proximal and distal neck was high (r = 0.99; p < 0.001). Three-dimensional analysis enhanced interpretation of the tomographic images by visualizing the spatial position of anatomic structures and contributed to understanding the shape and dimensions of the aneurysm. CONCLUSIONS: Intravascular ultrasonography provides accurate information on the vessel wall, lesion morphologic characteristics, and quantitative parameters of the abdominal aorta. Spatial information supplied by three-dimensional analysis contributes to a more realistic interpretation of the tomographic images.

Femorodistal venous bypass evaluated with intravascular ultrasound.

OBJECTIVE: To evaluate the feasibility of intravascular ultrasound imaging during femorodistal venous bypass procedures to assess qualitative and quantitative parameters of the greater saphenous vein and to detect potential causes for (re)stenosis and/or occlusion. METHODS: Intravascular ultrasound data obtained from 15 patients were reviewed and compared with angiographic data. RESULTS: Intravascular ultrasound enabled differentiation between normal and thickened vein wall. Venous side-branches could be located. Intact valves could be differentiated from valves disrupted by valve cutting. Patent anastomoses could be distinguished from anastomoses with some degree of obstruction. Intravascular ultrasound imaging of the inflow and outflow tracts revealed obstructive lesions, not evidenced angiographically. Quantitative analysis revealed that the median normal vein wall thickness (tunica intima and tunica media) was 0.25 mm (range 0.17-0.40 mm). The distinct vein wall thickening encountered in three patients measured 0.82, 0.95 and 1.06 mm, respectively, and was associated with narrowing in two patients. In five of 15 patients intravascular ultrasound findings altered surgical management. CONCLUSION: Intravascular ultrasound is able to assess qualitative and quantitative parameters of the venous bypass and has the potential to influence surgical management based on morphologic and quantitative data.