[Ruptures of popliteal artery aneurysms]. / Razryv anevrizmy podkolennoi arterii.

AIM: To improve diagnosis and surgical outcomes in patients with ruptured popliteal artery aneurysm. MATERIAL AND METHODS: Eight patients with ruptured popliteal artery aneurysm have undergone surgery for the period from 1999 to 2015 at the Vascular Surgery Department of Sklifosovsky Research Institute for Emergency Care. Incidence of rupture was 2.9% from total number of popliteal artery aneurysm. 7 patients with rupture had signs of lower limb ischemia (acute form grade I in 2 (25%) cases, grade IIA in 1 (12.5%), grade IIB in 1 (12.5%) case, chronic ischemia grade IIB in 2 (25%) patients, grade III in 1 (12.5%) patient). 1 (12,5%) patient had not lower limb ischemia. Preoperatively all patients underwent sonography of lower limb arteries and soft tissues, computed tomography of the same structures was carried out in 3 patients, 5 patients underwent subtraction digital angiography. Presence and dimensions of soft tissues hematoma, arterial perfusion proximally and distally to popliteal artery, aneurysms of contralateral limb and other localizations were assessed. RESULTS: Amputations after surgical repair were absent in 6 patients. Five patients were discharged with patent graft, completely compensated blood flow and primary healing of postoperative wound. Severe postoperative complications followed by amputation occurred in 2 patients. One patient died with reperfusion syndrome, hematoma and graft infection, sepsis. CONCLUSION: 1) Ruptured popliteal artery aneurysm is extremely rare complication, however it is a formidable event with high risk of amputation and death. 2) Early diagnosis of popliteal artery aneurysm and surgical treatment prior to embolism, thrombosis and rupture are necessary to prevent formidable complications. 3) Timely detection of aneurysms and their complications by general practitioners is extremely low due to rarity and specificity of the disease, presence of various symptoms. It is necessary to popularize knowledge about this disease among general practitioners. 4) Sonography is screening method for differential diagnosis. 5) CT-angiography or subtraction angiography are advisable to assess distal perfusion if patient's state is stable without severe ischemia. 6) Aneurysm repair with popliteal artery replacement should be performed in early period after rupture in order to reduce time of ischemia and to prevent infection of hematoma in view of ischemia and anemia.

Monodisperse spherical mesoporous silica particles: fast synthesis procedure and fabrication of photonic-crystal films.

A procedure for the synthesis of monodisperse spherical mesoporous silica particles (MSMSPs) via the controlled coagulation of silica/surfactant clusters into spherical aggregates with mean diameters of 250-1500 nm has been developed. The synthesis is fast (taking less than 1 h) because identical clusters are simultaneously formed in the reaction mixture. The results of microscopic, x-ray diffraction, adsorption and optical measurements allowed us to conclude that the clusters are ∼15 nm in size and have hexagonally packed cylindrical pore channels. The channel diameters in MSMSPs obtained with cethyltrimethylammonium bromide and decyltrimethylammonium bromide as structure-directing agents were 3.1 ± 0.15 and 2.3 ± 0.12 nm, respectively. The specific surface area and the pore volume of MSMSP were, depending on synthesis conditions, 480-1095 m(2) g(-1) and 0.50-0.65 cm(3) g(-1). The MSMSP were used to grow opal-like photonic-crystal films possessing a hierarchical macro-mesoporous structure, with pores within and between the particles. A selective filling of mesopore channels with glycerol, based on the difference between the capillary pressures in macro- and mesopores, was demonstrated. It is shown that this approach makes it possible to control the photonic bandgap position in mesoporous opal films by varying the degree of mesopore filling with glycerol.