Application of the cell-free matrix of the donor artery for plasty of posterior urethral strictures

Introduction. Urethral stricture is a complex and urgent problem in operative urology. The main problem in the treatment of extended structures of the posterior urethra is the inability to form an adequate urethral site for augmentation urethroplasty with the common buccal graft, which has a priority in the treatment of penile strictures. The use of tissue acellular matrices may be promising in the development of reconstructive urology, which in the future will solve a number of problems associated with augmentation urethroplasty. The purpose of this article is to study the possibility of using a cell-free matrix of a donor artery as a free flat flap for stricture replacement urethroplasty on a model of laboratory animals (rabbits). Materials and methods. Donor blood vessels were Used, which were subjected to detergent-enzymatic perfusion decellularization. To assess the quality of the cell-free matrix, a histological study and an immunohistochemical study were performed. The cell-free flap of the donor artery was fixed to the protein envelope from the side of the simulated defect and posterior on-lay urethroplasty was performed.Results and discussion. The resulting matrix was characterized by the absence of detectable cell nuclei, preserved type I collagen, and a DNA content of no more than 50 ng / mg of tissue. In the postoperative period, normal motor activity of animals, normal urination, weight loss was not observed. The levels of C- reactive protein, creatinine, and urea in peripheral blood 5 months after surgery were within the normal range: 0.285±0.04839 mg / l, 93.5±8.057 mm / l, and 8.35±1.355 mm/l, respectively. If cystourethrography with the help of computer tomography data for stricture of the urethra is not revealed. During magnetic resonance imaging in the axial and sagittal projections, the patency of the urethra was indirectly confirmed. Conclusion. In a laboratory animal model, it was shown that the resulting cell-free flap has in vivo biocompatibility and can be used for replacement urethroplasty of posterior urethral strictures.

Bypass Procedure Performed in the Field of a Decompressive Craniectomy in the Case of an MCA Dissecting Aneurysm: Case Report and Review of the Literature

Treatment of complex aneurysms often requires additional surgical tools including the use of the extra-intracranial (EC-IC) bypass. The following report depicts the utilization of the EC-IC bypass in treating a dissecting aneurysm several hours after a salvage emergent evacuation of an acute subdural hematoma via decompressive craniectomy (DC). Preserving the superficial temporal artery during the DC provided a donor artery for the bypass surgery.

The dynamic effect of coronary artery bypass grafting on the instantaneous wave-free ratio in the collateral donor artery of a patient with chronic total occlusion

Physiological assessment is challenging in patients with multivessel disease (MVD) with a chronic total occlusion (CTO) and may result in inappropriate treatment decisions. We report herein, for the first time to our knowledge, on the dynamic changes of the instantaneous wave-free ratio in the CTO collateral donor artery before and after coronary artery bypass grafting (CABG). Our case highlights the paramount importance of collateral circulation when interpreting invasive indices of coronary stenosis severity to guide decision-making for CABG in MVD patients with a CTO. This may be particularly relevant to reduce the risk of early graft failure in patients with MVD undergoing CABG.

Time-dependent improvement in coronary flow reserve in collateral donor artery following successful recanalization of the Coronary Chronic Total Occlusion

Background Coronary chronic total occlusion (CTO) is characterized by the presence of collateral blood vessels which can provide additional blood supply to CTO-artery dependent myocardium. Successful CTO recanalization is followed by significant decrease in collateral donor artery blood flow and collateral derecruitment. Purpose Study aim was to assess time-dependent changes in coronary flow reserve (CFR) in collateral donor artery after CTO recanalization and identify factors that influence these changes. Methods Our study enrolled 31 patients with CTO scheduled for percutaneous coronary intervention (PCI). Non-invasive CFR was measured before PCI in collateral donor artery, and 24h and 6 months post-PCI in CTO and collateral donor artery. Gated SPECT MIBI was performed before PCI, while quality of life was assessed by Seattle angina questionnaire (SAQ) pre-PCI, and 6 months after PCI. Results Collateral donor artery showed significant increase in CFR 24h after CTO recanalization compared to pre-PCI values (2.30±0.49 vs. 2.71±0.45, p=0.005), which remained unchanged after 6 months (2.68±0.24). Maximum baseline blood flow velocity of the collateral donor artery showed significant decrease measured 24h post-PCI compared to pre-PCI values (0.28±0.06 vs. 0.24±0.04m/s), and remained similar after 6-months. There was no significant difference in maximum hyperemic blood flow velocity pre-PCI, 24h and 6 months post-PCI. CFR change of the collateral donor artery 24h post-PCI compared to pre-PCI values showed inverse correlation with left ventricle ejection fraction (LVEF) measured on SPECT. CFR changes showed no correlation with the changes in quality of life assessed by SAQ post-PCI compared to pre-PCI. Conclusions Significant increase in CFR of the collateral donor artery was observed within 24h after successful recanalization of CTO artery, which maintained constant after the 6 months follow-up. This increase was largely driven by the significant reduction in the maximum baseline blood flow velocity within 24h after CTO recanalization compared to pre-PCI values. Our results suggest that possible benefit of CTO recanalization could be the improvement in physiology of the collateral donor artery. Funding Acknowledgement Type of funding source: None

Direct double bypass using the posterior auricular artery as initial surgery for moyamoya disease: technical note

Surgical treatments for moyamoya disease (MMD) include direct revascularization procedures with proven efficacy, for example, superficial temporal artery (STA) to middle cerebral artery (MCA) bypass, STA to anterior cerebral artery bypass, occipital artery (OA) to MCA bypass, or OA to posterior cerebral artery bypass. In cases with poor development of the parietal branch of the STA, the posterior auricular artery (PAA) is often developed and can be used as the bypass donor artery. In this report, the authors describe double direct bypass performed using only the PAA as the donor in the initial surgery for MMD.In the authors’ institution, MMD is routinely treated with an STA-MCA double bypass. Some patients, however, have poor STA development, and in these cases the PAA is used as the donor artery. The authors report the use of the PAA in the treatment of 4 MMD patients at their institution from 2013 to 2016. In all 4 cases, a double direct bypass was performed, with transposition of the PAA as the donor artery. Good patency was confirmed in all cases via intraoperative indocyanine green angiography and postoperative MRA or cerebral angiography. The mean blood flow measurement during surgery was 58 ml/min. No patients suffered a stroke after revascularization surgery.

Coronary physiology before and after chronic total occlusion treatment: what does it tell us?

Studies performed in the last two decades demonstrate that after successful percutaneous coronary intervention (PCI) of a chronically occluded coronary artery, the physiology of the chronic total occlusion (CTO) vessel and dependent microvasculature does not normalise immediately but improves significantly over time. Generally, there is an increase in fractional flow reserve (FFR) in the CTO artery, a decrease in collateral blood supply and an increase in FFR in the donor artery accompanied by an increase in blood flow and decrease in microvascular resistance in the myocardium supplied by the CTO vessel. Analogous to these physiological changes, positive remodelling of the distal CTO artery also occurs over time, and intravascular imaging can be helpful for analysing distal vessel parameters. Follow-up coronary angiography with physiological measurements after several weeks to months can be helpful and informative in a subset of patients in order to decide upon the necessity for treatment of residual coronary artery stenosis in the vessel distal to the CTO or in the contralateral donor artery, as well as in deciding whether stent optimisation is indicated. We suggest that such physiological guidance of CTO procedures avoids unnecessary overtreatment during the initial procedure, guides interventions at follow-up, and improves our understanding of what PCI in CTO means.

Matching Selection of Donor-Recipient Vessels in Revascularization Surgery Effectively Reduce the Incidence of Postoperative Hyperperfusion Syndrome in Adult Moyamoya Disease: A Retrospective Comparison Study

Introduction: Cerebral hyperperfusion syndrome (CHS) is one of the most serious complications after revascularization surgery in patients with moyamoya disease (MMD). However, there are few effective measures to prevent the occurrence of CHS. Objective: The present study aims to examine the effect of the method about matching selection of donor-recipient vessels during revascularization surgery on the incidence of postoperative CHS in adult MMD patients. Methods: 216 Chinese adult patients with MMD received surgery treatment between January 2018 and December 2019 in our hospital were enrolled in this study. 191 out of 216 patients were included in this study. Matching selection method was defined as follows: (1) blood flow: the direction of blood flow and speed of the donor artery and potential receptor arteries were measured by flow 800 indocyanine green video angiography; (2) vascular diameter: the diameters of the donor artery and potential receptor arteries by a miniature ruler. Only the artery with antegrade flow and with smallest difference in flow speed and diameter with the donor artery will be selected as the receptor artery to perform anastomosis. Matching selection was performed from January 2019. Digital subtraction angiography was performed in all patients for initial MMD diagnosis. Perioperative cerebral perfusion and related clinical symptoms were monitored. Clinical characteristics, contralateral progression, and risk factors were reviewed. The incidence of CHS and the correlation of CHS with baseline characteristics or clinical conditions were analyzed. Results: Of these 191 patients, 82 patients received matching selection of donor-recipient vessels during revascularization surgery and 109 patients without. The postoperative CHS incidence in the matching group was 3.66%, which was much lower than that in the nonmatching group (15.60%). Multivariate analysis did not reveal a significant risk factor between the progression group and the nonprogression group. Correlation analysis revealed only the matching selection method was significantly associated with the reduced postoperative CHS incidence in MMD patients. Conclusions: The matching selection of donor-recipient vessels during revascularization surgery effectively reduces the incidence of postoperative CHS in adult patients with MMD.

Clinical importance of the occipital artery in vascular lesions: A review of the literature

The occipital artery (OA) is a critical artery in vascular lesions. However, a comprehensive review of the importance of the OA is currently lacking. In this study, we used the PubMed database to perform a review of the literature on the OA to increase our understanding of its role in vascular lesions. We also provided our typical cases to illustrate the importance of the OA. The OA has several variations. For example, it may arise from the internal carotid artery or anastomose with the vertebral artery. Therefore, the OA may provide a crucial collateral vascular supply source and should be preserved in these cases. The OA is a good donor artery. Consequently, it is used in extra- to intracranial bypasses for moyamoya disease (MMD) or aneurysms. The OA can be involved in dural arteriovenous fistula (DAVF) and is a feasible artery for the embolisation of DAVF. True aneurysms and pseudoaneurysms can occur in the OA; surgical resection and embolisation are the effective treatment approaches. Direct high-flow AVF can occur in the OA; embolisation treatment is a good option in such cases. The OA can also be involved in MMD and brain arteriovenous malformation (AVM) by forming transdural collaterals. For a patient in the prone position, if occipital and suboccipital craniotomies are performed, the OA can also be used for intraoperative angiography. In brief, the OA is a very important artery in vascular lesions.

A Method of Mobilization of the Lower Epigastric Artery for Bypass Penile Revascularization Surgery

The effectiveness of microsurgical revascularization performed according to indications ranges from 85.3% within the first three years of observation and up to 65.5 % during a five-year follow-up. These data are significant evidence of the necessity to rationalize both the indications for this kind of surgery and the surgical techniques. Five revascularization operations were performed using the Virag II and Michal II technique in the Sharlip modification with a satisfactory result. Two-stage combined revascularization, including angioplasty and stent placement in the common iliac artery as the first stage and open penile revascularization surgery as the second stage was performed in one patient. In all the cases, the lower epigastric artery (epigastrica inferior) was used as a donor artery for bypass epigastric-penile anastomosis. The article discusses issues of the mobilization of the above artery for its use as a donor shunt, as well as methods of prevention and diagnosis of arterial thrombosis in it in the postoperative period with the use of duplex ultrasound and angiography.