[Acute mesenteric ischemia - a 15-year experience of surgical treatment in a multi-field hospital]. / Ostraya arterial'naya mezenterial'naya ishemiya ­ 15-letnii opyt khirurgicheskogo lecheniya v mnogoprofil'nom statsionare.

OBJECTIVE: To evaluate the results of surgical treatment of arterial acute mesenteric ischemia in a single hospital over a 15-year period (from 2007 to 2022). MATERIAL AND METHODS: There were 385 patients with acute occlusion of superior or inferior mesenteric artery over a 15-year period. The causes of acute mesenteric ischemia were thromboembolism of superior mesenteric artery (51%), its thrombosis (43%) and thrombosis of inferior mesenteric artery (6%). Female patients predominated (258 or 67%), while male patients comprised 33% (n=127). Age of patients ranged from 41 to 97 years (mean 74±9). The main diagnostic method for acute intestinal ischemia was contrast-enhanced computed tomography or CT angiography. Intestinal revascularization was performed in 101 patients: 10 patients - open embolectomy or thrombectomy from superior mesenteric artery, 41 patients - endovascular intervention, 50 patients - combined surgery (revascularization with resection of necrotic bowel segments). Isolated resection of necrotic intestines was performed in 176 patients. Exploratory laparotomy was performed in 108 patients with total bowel necrosis. Prevention and treatment of reperfusion and translocation syndrome after successful intestinal revascularization implied extracorporeal hemocorrection for extrarenal indications (veno-venous hemofiltration or veno-venous hemodiafiltration). RESULTS: Overall 15-year mortality rate (385 patients) for acute SMA occlusion was 71% (256 out of 360 patients), postoperative mortality excluding exploratory laparotomies for the same time period - 59%. Mortality rate for inferior mesenteric artery thrombosis was 88%. Routine CT angiography of mesenteric vessels, active and effective early intestinal revascularization (open or endovascular surgery), as well as extracorporeal hemocorrection methods for reperfusion and translocation syndrome reduced mortality rate to 49% over the past 10 years (from 2013 to 2022). Mortality in acute mesenteric ischemia in the first 5 years of this study (from 2007 to 2012) was 64% (p=0.16). The main cause of death was intestinal gangrene with multiple organ failure. Reperfusion syndrome after effective endovascular revascularization complicated by severe pulmonary edema and acute respiratory distress syndrome resulted death in 15% of patients. CONCLUSION: Acute mesenteric ischemia is followed by high mortality rates and extremely poor prognosis. Early diagnosis of acute intestinal ischemia using modern diagnostic methods (CT angiography of mesenteric vessels), effective revascularization of superior mesenteric artery (open, hybrid or endovascular), prevention and treatment of reperfusion and translocation syndrome can improve postoperative outcomes.

[Gas in superior mesenteric artery and celiac axis as a rare CT-sign of extensive bowel necrosis]. / Gaz v verkhnei bryzheechnoi arterii i chrevnom stvole kak redkii KT-priznak obshirnogo nekroza kishechnika.

The authors report endovascular treatment of acute thromboembolic occlusion of superior mesenteric artery in a 75-year-old patient whose postoperative period was complicated by massive reperfusion and translocation syndrome. Contrast-enhanced CT in 12 hours after successful thrombectomy from superior mesenteric artery revealed CT signs of irreversible bowel lesion, i.e. gas in hepatic veins, intestinal wall and mesenteric veins, bowel wall thinning. In addition, CT revealed extremely rare sign of severe acute mesenteric ischemia (gas in superior mesenteric artery and celiac axis). We found no description of gas in celiac axis following acute mesenteric ischemia in available literature.

[Venous thromboembolic complications in patients with intracerebral hemorrhage]. / Venoznye tromboembolicheskie oslozhneniya u patsientov s gemorragicheskim insul'tom.

OBJECTIVE: To evaluate the effectiveness and safety of various heparin therapy regimens for venous thromboembolic complications in patients with acute cerebral circulatory disorders of the hemorrhagic type. MATERIAL AND METHODS: In a prospective single-center study, treatment results of 62 patients with hypertensive brain hematoma were analyzed. All patients were divided into two comparable groups: the group of «very early¼ prophylactic heparin therapy or the first 48 hours from the moment of the disease (n=35) and the group of «early¼ prophylactic heparin therapy, or later than 48 hours from the moment of the intracerebral hematoma development (n=27). The end points of the study were: venous thrombosis, pulmonary embolism (fatal and non-fatal), recurrent intracerebral hemorrhage, other clinically significant hemorrhagic complications, and intrahospital mortality. RESULTS: In the group of «very early¼ and «early¼ prophylactic heparin therapy, the results were as follows: venous thrombosis 22.9% vs. 29.6% (p=0.36), total rate of PE 2.9% vs. 11.1% (p=0.03), nonfatal PE 0% vs. 7.4% (p=0.007), fatal PE 2.9% vs. 3.7% (p=0.76), recurrent intracerebral hemorrhage and other hemorrhagic complications 0% in both groups, intrahospital mortality was 54.3% versus 48.1% (p=0.54). CONCLUSION: The earliest administration of direct anticoagulants in prophylactic doses in patients with hemorrhagic stroke leads to the decrease in the frequency of venous thrombosis and thromboembolic complications, without being accompanied by the development of repeated intracranial and other hemorrhagic events.

[Carotid endarterectomy and carotid artery stenting in advanced age patients]. / Karotidnaya endarterektomiya i stentirovanie vnutrennei sonnoi arterii u patsientov starshikh vozrastnykh grupp (obzor literatury).

The manuscript is devoted to world experience of carotid endarterectomy and carotid artery stenting in advanced age patients. Some authors report the advantages of endovascular surgery in elderly patients while the others prefer carotid endarterectomy. Senile patients (75-80 years old) with asymptomatic internal carotid artery stenosis is one of the most difficult group for the management. This is due to a more complex assessment of perioperative surgical risk, high incidence of complicated atherosclerotic plaques in carotid arteries and dubious benefits of surgery considering short life expectancy and severe comorbidities. Accumulation of experience in the management of advanced age patients should be valuable for either optimizing or individualizing surgical strategy.

[Endovascular surgery for acute mesenteric ischemia]. / Éndovaskuliarnaia khirurgiia ostrogo arterial'nogo narusheniia mezenterial'nogo krovoobrashcheniia: podkhody k lecheniiu.

OBJECTIVE: To demonstrate the results of endovascular treatment of 15 patients with acute mesenteric ischemia. MATERIAL AND METHODS: There were 15 patients with acute mesenteric ischemia who underwent surgery (9 men and 6 women). Mean age was 77±11 years. Acute intestinal ischemia was caused by thromboembolism of superior mesenteric artery (9 patients), thrombosis of superior mesenteric artery (5 patients) and critical stenosis of the ostia of superior mesenteric artery and celiac trunk (1 patient). Mean time from clinical manifestation of disease to admission to the hospital was 13 hours (range 2-72 hours). In-hospital development of acute mesenteric ischemia was noted in 2 patients. Indications for endovascular intervention and techniques of endovascular revascularization of superior mesenteric artery are described in the article. RESULTS: Blood flow restoration in superior mesenteric artery was achieved in 14 (93%) out of 15 patients. Laparotomy was required in 4 (27%) patients for extensive resection of necrotic intestine (n=1, 6.7%), local resection of small bowel (n=2, 13%). In another (6.7%) patient, intestine was recognized as viable after laparotomy. A bulk of intestine was preserved in most patients (n=14, 93%). In-hospital mortality rate was 47% (7 patients died). The main cause of nosocomial death (6 cases) was reperfusion syndrome followed by respiratory distress syndrome and multiple organ failure. CONCLUSION: New methods of prevention and treatment of reperfusion syndrome can improve the results of treatment of acute mesenteric ischemia.

[Results of endovascular treatment of acute tandem occlusion of internal carotid and middle cerebral arteries]. / Rezul'taty endovaskulyarnogo lecheniya ostroi tandemnoi okklyuzii vnutrennei sonnoi i srednei mozgovoi arterii.

OBJECTIVE: To evaluate the results of endovascular treatment of patients with ischemic stroke caused by acute tandem occlusion of the internal carotid and middle cerebral arteries (ICA and MCA). MATERIAL AND METHODS: Endovascular intervention was performed in 8 patients with tandem occlusion of ICA and MCA. The neurological deficit on admission was 17.4±5.6 NIHSS points and the average ASPECTS score was 9.5±0.8. The time from the onset of neurological symptoms to reperfusion was 224±68 min. Thrombolytic therapy was initiated before brain revascularization and continued intraoperatively in 4 out of 8 patients. ICA stenting after aspiration thrombectomy was required in 6 patients. Both antegrade (n=4) and retrograde (n=2) methods of brain revascularization were used. RESULTS: The rate of detection of tandem lesion in patients with ischemic stroke who underwent endovascular treatment was 5.4%. Technical success in restoring blood flow in the ICA basin at extra-and intra-cranial levels (mTICI 2b/3) was achieved in 7 (87.5%) patients. Intracranial hemorrhagic complications that affected the outcome of the disease were clinically significant in 25% of patients (n=2). The mortality rate was 37.5% (n=3). A satisfactory clinical result (a deficit of 0-2 mRS scores) was achieved at discharge in one of 5 surviving patients. CONCLUSION: Further studies of choosing the optimal surgical tactics for tandem occlusion of ICA and MCA, taking into account its effectiveness and safety, are need.

[Endovascular treatment of tandem occlusion of internal carotid and middle cerebral arteries in acute ischemic stroke]. / Éndovaskuliarnoe lechenie tandemnoi ostroi okkliuzii vnutrennei sonnoi i srednei mozgovoi arterii pri ostrom ishemicheskom insul'te.

The paper presents the literature data concerning the results and surgical approaches to the treatment of tandem occlusion in the ICA system. The authors describe two clinical cases of endovascular treatment of tandem ipsilateral occlusion of ICA and middle cerebral artery (MCA). In both cases, the cause of two-level occlusion was complicated by thrombosis atherosclerotic plaque in ICA in the extracranial part with distal thromboembolism in SMA. The antegrade endovascular approach was used in both patients, when ICA was stented at the first stage, and at the second stage aspiration thrombectomy from SMA was performed. The period from the onset of symptoms to revascularization of the ICA system was 285±63 minutes. There were no fatal outcomes, patients were discharged with different neurological deficits: scores of the first patient were as following: 2 points on the NIHSS, 1 point on a Rankin scale, 13 points (initial 12 points on NIHSS) on the Rivermead mobility index and of the second patient: 14 points on the NIHSS, 5 points on a Rankin scale, 0 points (of the original 17 points on the NIHSS) on the Rivermead mobility index.

Neovascularization of Carotid Atherosclerotic Plaque and Quantitative Methods of Its Dynamic Assessment in Vivo.

The study demonstrates significant variety of neovascularization degree and vessel diameter in the carotid atherosclerotic plaque. It is suggested that the increase in the number of vessels with a diameter <20 µ can be indicative of increased atherosclerosis activity, while the increase in the number of vessels with a diameter ≥40 µ indicates "reparative potential" of plaques. Duplex contrast-enhanced ultrasound scanning allows characterization of the localization and number of vessels with a diameter of ≥30 µ in the plaque, while even slight elevation of plasma concentration of basic fibroblast growth factor attests, first of all, to increased content of small vessels <30 µ in the plaque. The level of fibroblast growth factor >1.5 pg/ml is a reliable marker of increased number of both small and large vessels in the plaque.

[Diagnosis and treatment of extracranial internal carotid artery lesion combined with cerebrovascular malformation]. / Diagnostika i lechenie porazhenii ékstrakranial'nogo otdela vnutrennei sonnoi arterii v sochetanii s sosudistoi mal'formatsiei golovnogo mozga.

AIM: To analyze own experience of diagnosis and treatment of patients with extracranial internal carotid artery lesion and cerebrovascular malformations. MATERIAL AND METHODS: There were 16 patients with combined lesion of extracranial and intracranial internal carotid artery for the period January 2013 - December 2014. Occlusive-stenotic lesion and tortuosity of ICA were observed in 11 and 5 cases respectively. RESULTS: Incidence of combined ICA lesion was 5.2% (16 out of 308 observations of extracranial internal carotid artery lesion). Surgical treatment was performed in 7 patients including two-stage intervention in 4 cases and simultaneous surgery in 3 cases. Mean time between neurosurgical and vascular stages was 6 months. Complications and mortality were absent. CONCLUSION: Two-stage surgical approach with intracerebral vascular malformation correction followed by extracranial ICA reconstruction may be safe and effective in patients with combined lesion of ICA. Further trials are necessary for certain conclusions.

[Early reconstruction of brachiocephalic arteries as a prevention of recurrent ischemic stroke]. / Ranniaia rekonstruktsiia brakhitsefal'nykh arterii kak profilaktika povtornogo ishemicheskogo insul'ta.

AIM: To assess an efficacy and safety of brachiocephalic arteries reconstruction at the acute stage of stroke. MATERIAL AND METHODS: Early reconstruction of brachiocephalic arteries was made in 7 patients (mean age 67±9 years). Mean terms of brachiocephalic arteries reconstruction after stroke were 4.6 days (range 2-7 days). Pre- and postoperative neurological state was assessed by NIHSS score (mean preoperative score was 3.9±2.7 in these 7 patients, range 0-7). All patients had ipsilateral cerebral ischemic lesions with stenosis/occlusion of brachiocephalic artery. Their mean dimension was 10 mm (range 4-32 mm). Internal carotid artery stenting was made in 2 patients, carotid endarterectomy - in 4 patients, stenting of the 1st segment of left subclavian artery - in 1 patient. RESULTS: There were no deaths and recurrent postoperative ischemic strokes. Complications developed in 2 patients: postoperative hematoma and intraoperative transient ischemic attack during ICA stenting in 5 days after stroke. There was a positive course of neurological state after brachiocephalic arteries reconstruction: mean score of neurological deficit decreased by almost 2 times (from 3.9±2.7 to 2±1.7). CONCLUSION: Early surgical prevention (within 7 days after stroke) may be effective and safe in certain patients with ischemic stroke (neurological deficit by Rankin score ≤3 and NIHSS ≤7, ischemic focus dimension less than 4 cm). Brachiocephalic arteries reconstruction early after stroke improves neurological state postoperatively by reducing motor and sensitive disorders. However, at present time there are no clear indications for early revascularization depending on either neurological deficit severity and ischemic focus dimension. So, our data should be confirmed by large trials.

[Stenting of the superior mesenteric artery in a patient with severe chronic intestinal ischaemia].

Presented herein is a clinical case report concerning endovascular treatment of severe chronic ischaemia of digestive organs in a patient with lesions of all three visceral arteries. Peculiarities of endovascular technique in mechanical revascularization of the superior mesenteric artery are described. Restoration of blood flow through even one visceral artery, i. e., superior mesenteric artery, is an effective and safe method of treatment for chronic intestinal ischaemia.

[Early reconstruction of supra-aortic vessels as a prevention of recurrent ischemic stroke]. / Rannyaya revaskulyarizatsiya golovnogo mozga kak profilaktika povtornogo ishemicheskogo insul'ta.

AIM: To evaluate the efficacy and safety of supra-aortic vessels reconstruction within acute period of stroke. MATERIAL AND METHODS: Early surgery was performed in 7 patients aged 67±9 years. Revascularization was made after 4.6 days after ischemic stroke on the average (range from 2 to 7 days). Neurological status before and after surgery was assessed using NIHSS scale, mean preoperative score was 3.9±2.7 (0-7). All patients had ischemic brain lesions (4-32 mm, mean 10 mm) unilateral with carotid stenosis or occlusion. Carotid artery stenting was performed in 2 patients, carotid endarterectomy - in 4 patients and stenting of segment I of the left subclavian artery was made in 1 case. RESULTS: There were no mortality and recurrent postoperative ischemic stroke. Complications occurred in two patients: postoperative hematoma and intraoperative transient ischemic attack that developed during CAS after 5 days of a stroke. There was positive neurological dynamics after revascularization: there was almost 2-fold decrease of mean score of neurological deficit (from 3.9±2.7±1.7 to 2). CONCLUSION: Early surgical prevention of recurrent stroke (up to 7 days) can be performed effectively and safely in carefully selected patients with ischemic stroke (neurological deficit less than 3 Rankin scores and less than 7 NIHSS scores, ischemic lesion dimensions lass than 4 cm). Reconstruction of supra-aortic vessels in acute stage of stroke improves the neurological status and reduces the degree of motor and sensory disorders. However, currently there are no clear criteria for inclusion and exclusion of patients for early revascularization using both degree of neurological deficit and size of ischemic lesion. So our results need to be confirmed by large trials.

[Endovascular interventions for acute ischemia of intestine].

It is presented 5 clinical observations of acute ischemia of intestine in which different endovascular interventions including isolated superior mesenteric artery stenting, rheolytic and aspiration thrombectomy and combination of techniques were applied. Surgical success with blood flow restoration in superior mesenteric artery was achieved in 4 of 5 patients. 2 patients have required laparotomy and intestinal resection. In 1 case extent of resection was significantly reduced after previous endovascular thrombectomy. There were no deaths. It is concluded that endovascular interventions may be considered as independent method of treatment of patients with acute mesenteric ischemia.

[Immunological aspects in spleen ruptures surgery due to closed abdominal trauma].

The remote results of immunity investigation in 30 patients after organ-preserving surgery and in 30 patients after splenectomy forspleen rupture are presented in the article. Indexes of cellular and humoral immunity were normal and life quality did not differ from that in healthy individuals after organ-preserving operations with splenic artery ligation. Splenectomy leads to deterioration of life quality and disorders in cellular immunity including decrease of T-helpers/inductors cells (CD4), immunoregulatory index (CD3/CD4) and general number of T-lymphocytes (CD3) in some cases on background of compensatory increase of normal killers (CD16). It was observed significant decrease of IgG and IgM levels. Values of IgA and cytokines IL-1, IL-2, IL-6 and TNF remained normal. Level of immunosuppression is reduced due to development of splenosis.

Single-mode all-silica photonic bandgap fiber with 20-microm mode-field diameter.

An all-silica photonic bandgap fiber with a cladding index difference of approximately 2 % and diameter-to-pitch ratio (d/wedge) of 0.12 was fabricated and studied. To our knowledge, this is the first report on the properties of photonic bandgap fiber with such a small d/wedge. The fiber is single-mode in the fundamental bandgap. The mode field diameter in the 1000-1200 nm wavelength range is 19-20 microm. The minimum loss in the same range is 20 dB/km for a 30-cm bending diameter. In our opinion, all-silica photonic bandgap fiber can serve as a potential candidate for achieving single-mode propagation with a large mode area.

Four-wave mixing with large stokes shifts in heavily Ge-doped silica fibers.

Four-wave mixing (FWM) in nonlinear germanosilicate fibers with GeO2 concentrations as high as 67 mol.% in the core is studied theoretically and experimentally. Large frequency shifts of 1875-3829 cm(-1) are observed in the mixed-mode pump parametric process. The dependence of FWM phase matching on the GeO2 concentration, core diameter, and index profile is demonstrated. The 2.5% conversion efficiency of an 887 nm signal to a 1.3 microm communication band is obtained at a 2 W cw pump power inside the fiber.