Objectives• To determine the optimal method for assessing stone volume, and thus stone burden, by comparing the accuracy of scalene, oblate, and prolate ellipsoid volume equations with three-dimensional (3D)-reconstructed stone volume.• Kidney stone volume may be helpful in predicting treatment outcome for renal stones. While the precise measurement of stone volume by 3D reconstruction can be accomplished using modern computer tomography (CT) scanning software, this technique is not available in all hospitals or with routine acute colic scanning protocols. Therefore, maximum diameters as measured by either X-ray or CT are used in the calculation of stone volume based on a scalene ellipsoid formula, as recommended by the European Association of Urology.
Methods• In all, 100 stones with both X-ray and CT (1-2-mm slices) were reviewed. Complete and partial staghorn stones were excluded.• Stone volume was calculated using software designed to measure tissue density of a certain range within a specified region of interest.• Correlation coefficients among all measured outcomes were compared. Stone volumes were analysed to determine the average 'shape' of the stones.
Results• The maximum stone diameter on X-ray was 3-25 mm and on CT was 3-36 mm, with a reasonable correlation (r = 0.77).• Smaller stones (<9 mm) trended towards prolate ellipsoids ('rugby-ball' shaped), stones of 9-15 mm towards oblate ellipsoids (disc shaped), and stones >15 mm towards scalene ellipsoids.• There was no difference in stone shape by location within the kidney.
Conclusions• As the average shape of renal stones changes with diameter, no single equation for estimating stone volume can be recommended.• As the maximum diameter increases, calculated stone volume becomes less accurate, suggesting that larger stones have more asymmetric shapes.• We recommend that research looking at stone clearance rates should use 3D-reconstructed stone volumes when available, followed by prolate, oblate, or scalene ellipsoid formulas depending on the maximum stone diameter.
Failure of aneurysm sealing following treatment with Nellix has been more common than anticipated and can cause aortic rupture. Post-operative surveillance of Nellix stent grafts is crucial to identify features of failure.
Social media has transformed communication among health care professionals. This narrative review article provides an update of practical guidelines for effective and professional use of these communication technologies.
Morphometric analysis predicts poorer outcome in a broad cohort of vascular surgery patients. Such assessment is likely to enhance patient counseling regarding individual risk as well as enhancing the ability to undertake risk-modified surgical audit.
Stents appear as a valid salvage option for infragenicular distal embolization when conventional methods fail; the likelihood of having to use a stent is higher for patients with critical limb ischaemia and a single-vessel run-off.
Introduction: Cerebral hyperperfusion syndrome (CHS) is a preventable cause of stroke after carotid endarterectomy (CEA). There are currently no pooled data available on the incidence of CHS after carotid artery stenting (CAS). The aim of this review was to assess the relevance of CHS in the procedural stroke rate following CAS. Method: A systematic search on incidence rates of CHS after CAS was conducted in the MEDLINE, EMBASE, and Cochrane databases in November 2017. A meta-regression analysis was performed on CHS to explain heterogeneity and determine the impact of potential risk factors on observed CHS. The methodological quality of the included studies was assessed using the Cowley criteria. Results: The pooled CHS risk across 33 studies concerning 8731 CAS patients was 4.6% (3.1e6.8%). Stroke occurred in 47% of CHS patients, of which 54% were fatal or disabling. Average time from procedure to symptoms was 12 h (IQR 8e36 h). Impaired cerebrovascular reserve (CVR) was associated with a higher risk of CHS after CAS (RR 5.18; 95% CI 1.0e26.8; p = .049). Symptomatic status was associated with a lower risk of CHS (RR 0.20; 95% CI 0.07e0.59; p = .001). Conclusion: CHS is a serious and frequent complication in patients undergoing carotid angioplasty with stenting, and is most likely to occur in the very early post-procedural period. Future studies are encouraged to investigate the effect of intensive haemodynamic monitoring, including blood pressure control and assessment of cerebral blood flow, on the incidence of stroke caused by CHS after CAS.
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