Low rates of restenosis in primary lateral carotid artery endarterectomy

Carotid artery endarterectomy (CAE) is a treatment of choice for symptomatic and asymptomatic high-grade carotid stenosis, showing great results in reducing stroke morbidity. The optimal technique of the arterial closure is, however, still under discussion, with both patch angioplasty and primary closure having numerous advantages and pitfalls. The definite evidence is still lacking. The aim of this study was to evaluate the results of the modified primary closure technique during CEA. Incidence of restenosis more than 8 months after the surgery was measured. A retrospective observational study to evaluate modified primary internal carotid artery closure was conducted in Republican Vilnius University Hospital from January 1st, 2014 to December 31st, 2018. The patients were enrolled in the trial during their routine follow-up by their surgeon.  During the visit, after an informed consent was signed, a qualified investigator performed carotid duplex ultrasound scan, documenting the restenosis rates. Patients also filled in the comorbidity assessment questionnaire, which included their smoking habits, history of hypertension and their adherence to antihypertensive medication as well as cholesterol levels and statin therapy, additional related comorbidities. Out of 342 patients that underwent CAE with primary closure in the Republican Vilnius university hospital from 2014 to 2018, 42 patients were identified as deceased, therefore a follow-up was impossible. Out of planned 150 (50%) consequently selected patients, 125 gave an informed consent to be enrolled into the study. Out of those 6 pre-occlusions were established during the review of the patient medical data and therefore were excluded from the study. In general, we analyzed the data of 119 patients and 125 CAE with a modified primary suture closure. The mean follow-up time was 35.78 months (SE 0.992; SD 11,046). At the time of a follow up, 3 (2,4%) carotid artery occlusions were identified and promptly evaluated. Restenosis rates varied: 5,6% of patients had low grade (<50%), 5,6% had moderate grade (50-69%) and 1,6% had high grade (70-99%) stenosis. The modified lateral CAE with primary closure technique, used in our hospital’s contemporary practice has shown to be a promising alternative to the classical primary suture, due to reduced restenosis rates. More prospective and randomized studies are needed to evaluate this technique in comparison to other CAE closure techniques

Runge-Kutta methods for third order weak approximation of SDEs with multidimensional additive noise

A new class of third order Runge-Kutta methods for stochastic differential equations with additive noise is introduced. In contrast to Platen's method, which to the knowledge of the author has been up to now the only known third order Runge-Kutta scheme for weak approximation, the new class of methods affords less random variable evaluations and is also applicable to SDEs with multidimensional noise. Order conditions up to order three are calculated and coefficients of a four stage third order method are given. This method has deterministic order four and minimized error constants, and needs in addition less function evaluations than the method of Platen. Applied to some examples, the new method is compared numerically with Platen's method and some well known second order methods and yields very promising results.Comment: Two further examples added, small correction

Measures for increasing of company’s production capacity / Geresnio gamybinių pajėgumų naudojimo priemonės

Production capacity improvements are poorly explored areas of economic literature and the existing methods are difficult to apply. For this reason, the organization has only a superficial analysis of capacity, but after all this time, each production company had to improve the production capacity for the market economy and the most economical use of production factors. This article explores the company’s production capacity for better use of tools. It also presents the capacity of their concept, establishment, evaluates the factors leading to their production capacity, for developing efficiency measures and model presentation. Santrauka Straipsnyje nagrinėjamos įmonės gamybinių pajėgumų geresnio naudojimo priemonės. Atlikta mokslinės literatūros apžvalga, analizuojami gamybinių pajėgumų formavimo ir naudojimo teoriniai teiginiai. Taip pat apibūdinami gamybiniai pajėgumai, jų samprata, nustatymas, vertinami juos lemiantys veiksniai ir nurodomos jų didinimo priemonės. Tyrimo tikslas – gamybinių pajėgumų geresnio naudojimo priemonių modelio sudarymas. Raktiniai žodžiai: gamybiniai pajėgumai; gamybinių pajėgumų naudojimas; tobulinimas; gamybos veiksnia