Recommended standards for analyzing and reporting on lower extremity ischemia were first published by the Journal of Vascular Surgery in 1986 after approval by the Joint Council of The Society for Vascular Surgery and the North American Chapter of the International Society for Cardiovascular Surgery. Many of these standards have been accepted and are used in the current literature on peripheral arterial occlusive disease. With the passage of time, some oversights, aspects that require clarification, and better modifications have been recognized. This report attempts to correct these shortcomings while reinforcing those recommendations that have proven satisfactory. Explanatory comments are added to facilitate understanding and application. This version is intended to replace the original version.

Recent results for classical Be stars are reviewed and links to general astrophysics are presented. Classical Be stars are B-type stars close to the main sequence that exhibit line emission over the photospheric spectrum. The excess is attributed to a circumstellar gaseous component that is commonly accepted to be in the form of an equatorial disk. Since 1988, when the last such review was published, major progress has been made. The geometry and kinematics of the circumstellar environment can be best explained by a rotationally supported relatively thin disk with very little outflow, consistent with interferometric observations. The presence of shortterm periodic variability is restricted to the earlier type Be stars. This variation for at least some of these objects has been shown to be due to nonradial pulsation. For at least one star, evidence for a magnetic field has been observed. The mechanisms responsible for the production and dynamics of the circumstellar gas are still not constrained. Observations of nonradial pulsation beating phenomena connected to outbursts point toward a relevance of pulsation, but this mechanism cannot be generalized. Either the evidence that Be stars do not form a homogeneous group with respect to disk formation is growing or the short-term periodic variability is less important than previously thought. The statistics of Be stars investigated in open clusters of the Milky Way and the Magellanic Clouds has reopened the question of the evolutionary status of Be stars. The central B star is a fast rotator, although theoretical developments have revived the question of how high rotational rates are, so the commonly quoted mean value of about 70%-80% of the critical velocity may just be a lower limit. Be stars are in a unique position to make contributions to several important branches of stellar physics, e.g., asymmetric mass-loss processes, stellar angular momentum distribution evolution, astroseismology, and magnetic field evolution.

We present high resolution spectro-astrometry of a sample of 28 Herbig Ae/Be and 3 F-type pre-main sequence stars. The spectro-astrometry is shown from both empirical and simulated data to be capable of detecting binary companions that are fainter by up to 6 magnitudes at separations larger than 0.1 arcsec. The nine targets that were previously known to be a binary are all detected. In addition, we report the discovery of 6 new binaries and present 5 further possible binaries. The resulting binary fraction of 68+/-11 per cent is the largest reported for any observed sample of Herbig Ae/Be stars, presumably because of the exquisite sensitivity of spectro-astrometry for detecting binary systems. The data hint that the binary frequency of the Herbig Be stars is larger than for the Herbig Ae stars. The appendix presents model simulations to assess the capabilities of spectro-astrometry and reinforces the empirical findings. Two objects, HD 87643 and Z CMa, display evidence for asymmetric outflows. Finally, the position angles of the binary systems have been compared with available orientations of the circumprimary disc and these appear to be co-planar. The alignment between the circumprimary discs and the binary systems strongly suggests that the formation of binaries with intermediate mass primaries is due to fragmentation as the alternative, stellar capture, does not naturally predict aligned discs. The aligment extends to the most massive B-type stars in our sample. This leads us to conclude that formation mechanisms that do result in massive stars, but predict random angles beween the binaries and the circumprimary disks, such as stellar collisions, are also ruled out for the same reason.Comment: MNRAS accepted, 18 page

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The North American Symptomatic Carotid Endarterectomy Trial (NASCET) has thus far demonstrated conclusive benefit for carotid endarterectomy for patients with symptomatic 70% to 99% internal carotid artery (ICA) stenosis. In the NASCET, ICA stenosis was classified angiographically: % ICA stenosis = (1-[narrowest ICA diameter/diameter normal distal cervical ICA]) x 100%. However, widely used duplex scan criteria for ICA stenosis correlate with different angiographic categories of high-grade stenosis (50% to 79%, > 80%) and were developed on the basis of estimated bulb diameter. We therefore blindly evaluated with separate observers carotid angiograms from 100 patients who also underwent carotid duplex scanning in our vascular laboratory. Methods: "Angiographic stenosis" was calculated as in NASCET. Duplex scan measurements of ICA peak systolic velocity (PSV), ICA end-diastolic velocity, and the ratio of ICA PSV to common carotid artery (CCA) PSV were analyzed for sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy to identify a 70% to 99% ICA stenosis. Results: Analysis of the data revealed that an ICA PSV/CCA PSV ratio of 4.0 provided the best combination of sensitivity (91%), specificity (87%), positive predictive value (76%), negative predictive value (96%), and overall accuracy (88%) for detection of a 70% to 99% stenosis. Conclusion: We conclude duplex scan determination of 70% to 99% stenosis as defined in the NASCET requires the adoption of duplex criteria modified from those in current use in most vascular laboratories.

At the request of the Ad Hoc Committee on Reporting Standards of the Joint Council of the Society for Vascular Surgery and the North American Chapter of the International Society for Cardiovascular Surgery, this report updates and modifies "Reporting standards in venous disease" (J Vasc Surg 1988;8:172-81). As in the initial document, reporting standards for publications dealing with (1) acute lower extremity venous thrombosis, (2) chronic lower extremity venous insufficiency, (3) upper extremity venous thrombosis, and (4) pulmonary embolism are presented. Numeric grading schemes for disease severity, risk factors, and outcome criteria present in the original document have been updated to reflect increased knowledge of venous disease and advances in diagnostic techniques. Certain recommendations of necessity remain arbitrary. These standards are offered as guidelines whose observance will in our opinion improve the clarity and precision of communications in the field of venous disorders.

To our knowledge, this is the largest reported group of HHS patients. The characteristic angiographic appearance, histologic findings, and striking incidence of bilateral abnormalities in patients with unilateral symptoms lead us to conclude that HHS occurs when persons with preexisting palmar ulnar artery fibrodysplasia experience repetitive palmar trauma. This revised theory for the etiology of HHS explains why HHS does not develop in most patients with repetitive palmar trauma.

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