Development Of Collateral Vessels Research Articles

Lymphaticovenous anastomosis of the caudal thoracic duct to the azygous vein: A feline cadaver study.

The aim of this study was to describe a technique for anastomosis of the thoracic duct (TD) to the azygos vein (AV) using a microvascular anastomotic coupler (MAC) device in feline cadavers. Our hypothesis was that a TD-AV lymphaticovenous anastomosis would be feasible in feline cadavers. Cadaveric study. Eight domestic shorthair feline cadavers. A left paracostal laparotomy and 9th or 10th intercostal thoracotomy was performed. Contrast media was injected into a mesenteric lymph node and lymphography was used to identify the TD and its branches. The TD and AV were isolated, ligated, and divided with the aid of a surgical microscope. The TD and AV were anastomosed end-to-end using a 1.5 or 2.0 mm MAC. Intraoperative patency was assessed by manipulation of chyle and venous blood across the anastomosis. Mesenteric lymphography was repeated to confirm postoperative anastomotic patency. The TD was identified via lymphography in seven of eight cats. The anastomosis was successful and patency was confirmed via intraoperative assessment and postoperative lymphography in all cats. The median (range) duration for the dissection and anastomosis portions of the procedure was 122 (80-150) min. End-to-end anastomosis of the TD to the AV using a MAC was feasible in the feline cadaver without major intraoperative technical challenges. Anastomosis of the TD and AV may have application as an alternative treatment for idiopathic chylothorax in cats. By directly connecting the abdominal lymphatics to the central venous system, the stimulus for collateral vessel development around the site of TD ligation may be minimized, which may prevent leakage of chyle through the more cranial lymphatics.

Multi-parameter MRI-Based Machine Learning Model to Evaluate the Efficacy of STA-MCA Bypass Surgery for Moyamoya Disease: A Pilot Study.

Superficial temporal artery-middle cerebral artery (STA-MCA) bypass surgery represents the primary treatment for Moyamoya disease (MMD), with its efficacy contingent upon collateral vessel development. This study aimed to develop and validate a machine learning (ML) model for the non-invasive assessment of STA-MCA bypass surgery efficacy in MMD. This study enrolled 118 MMD patients undergoing STA-MCA bypass surgery. Clinical features were screened to construct a clinical model. MRI features were extracted from the middle cerebral artery supply area using 3D Slicer and employed to build five ML models using logistic regression algorithm. The combined model was developed by integrating the radiomics score (Rad-score) with the clinical features. Model performance validation was conducted using ROC curves. Platelet count (PLT) was identified as a significant clinical feature for constructing the clinical model. A total of 3404 features (851 × 4) were extracted, and 15 optimal features were selected from each MRI sequence as predictive factors. Multivariable logistic regression identified PLT and Rad-score as independent parameters used for constructing the combined model. In the testing set, the AUC of the T1WI ML model [0.84 (95% CI, 0.70-0.97)] was higher than that of the clinical model [0.66 (95% CI, 0.46-0.86)] and the combined model [0.80 (95% CI, 0.66-0.95)]. The T1WI ML model can be used to assess the postoperative efficacy of STA-MCA bypass surgery for MMD.

Anomalous Left Coronary Artery from the Pulmonary Artery (ALCAPA) Syndrome: Pathophysiology, Clinical Manifestations, and Management Strategies

Anomalous Left Coronary Artery from the Pulmonary Artery (ALCAPA) syndrome is a rare congenital cardiac anomaly characterized by the abnormal origin of the left coronary artery from the pulmonary artery instead of the aortic root. This anomaly results in compromised myocardial perfusion, particularly under conditions of increased oxygen demand, leading to myocardial ischemia, left ventricular dysfunction, and potentially severe complications such as mitral regurgitation, heart failure, and sudden cardiac death. The pathophysiology of ALCAPA involves a complex interplay of coronary artery steal phenomenon, collateral vessel development, and ventricular remodeling. Early diagnosis is critical, often achieved through echocardiography, cardiac MRI, or coronary angiography, which helps in planning surgical intervention. The mainstay of treatment is surgical correction to re-establish a dual coronary artery system, with techniques including direct reimplantation of the anomalous coronary artery into the aorta or the creation of an intrapulmonary tunnel. This article provides a comprehensive review of the current understanding of ALCAPA syndrome, emphasizing its pathophysiology, clinical presentation, diagnostic modalities, and surgical management, along with outcomes and prognostic factors.

Transcoronary Gradients of Mechanosensitive MicroRNAs as Predictors of Collateral Development in Chronic Total Occlusion.

Background and Objectives: In this present study, we investigated the impact of mechanosensitive microRNAs (mechano-miRs) on the collateral development in 126 chronic total occlusion (CTO) patients, selected from 810 undergoing angiography. Materials and Methods: We quantified the collateral blood supply using the collateral flow index (CFI) and assessed the transcoronary mechano-miR gradients. Results: The patients with favorable collaterals had higher CFI values (0.45 ± 0.02) than those with poor collaterals (0.38 ± 0.03, p < 0.001). Significant differences in transcoronary gradients were found for miR-10a, miR-19a, miR-21, miR-23b, miR-26a, miR-92a, miR-126, miR-130a, miR-663, and let7d (p < 0.05). miR-26a and miR-21 showed strong positive correlations with the CFI (r = 0.715 and r = 0.663, respectively), while let7d and miR-663 were negatively correlated (r = -0.684 and r = -0.604, respectively). The correlations between cytokine gradients and mechano-miR gradients were also significant, including Transforming Growth Factor Beta with miR-126 (r = 0.673, p < 0.001) and Vascular Endothelial Growth Factor with miR-10a (r = 0.602, p = 0.002). A regression analysis highlighted the hemoglobin level, smoking, beta-blocker use, miR-26a, and miR-663 as significant CFI determinants, indicating their roles in modulating the collateral vessel development. Conclusions: These findings suggest mechanosensitive microRNAs as predictive biomarkers for collateral circulation, offering new therapeutic perspectives for CTO patients.

Management of moyamoya disease: a review of current and future therapeutic strategies

Moyamoya disease (MMD) is characterized by idiopathic, progressive stenosis of the circle of Willis and the terminal portion of the internal carotid arteries with the development of prominent small collateral vessels and a characteristic moyamoya or puff-of-smoke radiographic appearance. The incidence and prevalence of MMD varies by region, age, and sex, with higher rates in Asian and East Asian populations compared to North American or European populations. There is a bimodal distribution of patients diagnosed with MMD. Pediatric patients are more commonly diagnosed within the 1st decade of life, whereas adult patients present in the 5th or 6th decade of life. Overall, there is a nearly 2:1 female-to-male ratio. Ischemic symptoms are the most common presentation in pediatric and adult populations, but adult patients are nearly twice as likely to present with intracranial hemorrhage compared to their pediatric counterparts. Surgical revascularization is indicated in symptomatic cases, and antiplatelet therapy may be a useful adjunct to prevent recurrent symptoms. Direct and combined bypass procedures seem to be more effective in adults, whereas children respond well to indirect bypass. The identification of key genetic, molecular, and environmental factors including RNF213 and GUCY1A3 loss-of-function mutations, angiogenic growth factors, autoantibodies, CNS infections, and radiation exposure suggest multiple pathways for the development of moyamoya arteriopathy. Further research is needed to better understand the heterogeneity of pathogenetic mechanisms that lead to moyamoya and to identify novel therapeutic targets to prevent, stabilize, and treat MMD.

Differences in collateral vessel formation after experimental retinal vein occlusion in spontaneously hypertensive rats and wild-type rats

ObjectiveRetinal vein occlusion (RVO) can lead to visual impairment, but the development of collateral vessels can sometimes mitigate significant damage. This study aimed to investigate the relationship between collateral vessels and hypertension, the most common underlying condition associated with RVO, by comparing spontaneously hypertensive rats (SHRs) and wild-type Wister rats (WWRs). We also examined the differences between WWRs and SHRs in terms of sphingosine 1-phosphate receptor 1 (S1PR1) expression and its product nitric oxide synthase 3 (NOS3) expression, which are involved in the formation of collateral vessels after vascular occlusion. MethodsLaser photocoagulation (PC) was used to occlude one randomly selected retinal vein in WWRs and SHRs, and the area surrounding the occluded vessel was examined using optical coherence tomography angiography. If reperfusion of the occluded vessel occurred within 2 weeks, the vessel was re-occluded repeatedly by PC. The number of eyes with successfully occluded vessels accompanied by collateral vessels was recorded. Then, WWRs and SHRs were divided into the following four groups: 1) control (no treatment), 2) vehicle (20% DMSO), 3) S1PR1 agonist (2 mg/mL SEW2871), and 4) S1PR1 antagonist (0.25 mg/mL VPC 23019) groups. The drugs were administered intravitreally in all groups except the control. The number of laser shots required for successful RVO was recorded. Histological evaluation and quantitative real-time PCR of S1PR1 and NOS3 were performed to elucidate the mechanisms underlying collateral vessel formation. ResultsThe proportion of eyes achieving successful vein occlusion was lower in SHRs (4/12 eyes, 33.3%) than in WWRs (8/10 eyes, 80%, p = 0.043). NOS3 expression at 6 h after PC was significantly higher in WWRs than in SHRs (p = 0.021). In WWRs treated with SEW2871, vein occlusion failed in 7 of 10 eyes (70%). The expression of NOS3 was significantly higher in the SEW2871 treatment group than in the untreated group (p < 0.001). Furthermore, NOS3 expression was significantly higher after SEW2871 treatment in WWRs than in SHRs (p = 0.011). ConclusionIn hypertensive environments, collateral vessels are less likely to develop, and S1PR1 may be involved in this phenomenon.

Chronic Limb-Threatening Ischemia: Management Updates and Common Questions

Chronic limb-threatening ischemia (CLTI) is an advanced form of peripheral vascular disease with high rates of morbidity and mortality. Patients often present with claudication, impaired walking, and ischemic pain. Screening for CLTI and peripheral arterial disease is recommended with ankle-brachial indexing. To prevent progression to CLTI, family medicine physicians can intervene with lifestyle modification of hyperlipidemia, obesity, smoking, and encouraging well-rounded high-fiber diets. OMT can be useful in increasing lower-extremity circulation and collateral-vessel development. If refractive to optimized medical management and lifestyle modification, surgical intervention is required. Regardless of intervention, CLTI maintains a high rate of morbidity and mortality, with halting progression being the primary objective.

Development of Collateral Vessels after Anterior Circulation Large Vessel Occlusion in Pediatric Arterial Ischemic Stroke Relates to Stroke Etiology: A Longitudinal Study.

The characteristics of large vessel occlusion (LVO) in the acute phase of pediatric arterial ischemic stroke and their natural history according to stroke etiology are poorly explored. This studied aimed at describing the prevalence and the radiological evolution of LVO in pediatric AIS. This single-center retrospective study included consecutive non-neonate children with acute arterial ischemic stroke, intracranial proximal LVO in the anterior circulation (MCA, anterior cerebral artery, and/or ICA), and clinical and imaging follow-up for at least 18 months, during a 9-year period. Intracranial LVO was observed in 24.8% of patients with anterior circulation arterial ischemic stroke and adequate follow-up (n = 26/105), with a median age of 4.2 years (IQR 0.8-9), sex ratio 1.16. The main stroke etiology associated with LVO was unilateral focal cerebral arteriopathy (n = 12, 46%). During follow-up, a specific pattern of unilateral poststroke anastomotic bridge was observed in 8/26 patients, with the poststroke development of nonperforating collaterals forming a bridge in bypass of the LVO site with visible distal flow, within a median delay of 11 months. The development of unilateral poststroke anastomotic bridge was only observed in patients with unilateral focal cerebral arteriopathy. No patient with this pattern experienced stroke recurrence or further progressive vascular modifications. After stroke, the development of unilateral poststroke anastomotic bridge is specifically observed in children with focal cerebral arteriopathy, appearing in the first year after stroke. This clinical-radiologic pattern was not associated with stroke recurrence or arterial worsening, differentiating it from progressive intracranial arteriopathy, such as Moyamoya angiopathy.

Acceleration of moyamoya disease after anti-vascular endothelial growth factor intravitreal injections

Abstract: Moyamoya disease (MMD) is a rare, progressive, irreversible vaso-occlusive disease affecting the cerebral vasculature. The progressive occlusion of blood vessels leads to the development of collateral vessels to compensate for the insufficient blood supply. Some growth factors such as vascular endothelial growth factor (VEGF) may cause excessive and aberrant angiogenesis in MMD. We report a case of a 55-year-old male, following up in retina clinics for diabetic retinopathy and macular edema who received anti-VEGF agents then he presented to the emergency room with left-sided face and body weakness, dysphagia, and dysarthria. Based on his clinical presentation and neuroimaging, he was diagnosed with moyamoya progression. We hypothesize that receiving anti-VEGF agents could have contributed to MMD progression in our patient and interfered with the collateral vessel development in a similar manner to their intended use in regressing neovascularization in diabetic retinopathy.

Impact of collateral vessels on Fontan circulation by using 0-1 dimensional Fontan circulation model considering concepts of oxygen supply and consumption

Abstract Background/Purpose In patients with univentricular heart disease, the Fontan operation has played a significant role in improving cyanosis and reducing the volume load on the systemic ventricle. However, Fontan patients may develop various complications, and their hemodynamics may deteriorate gradually, resulting in a poor long-term survival rate. Development of collateral vessels before and/or after the Fontan operation is one of the significant problems, and the patients may suffer from advanced cyanosis and heart failure. Although recent studies about the collateral vessels by MRI showed that a significant amount of blood is flown through the collateral vessels, little is known about its effect on the Fontan circulation. Therefore, understanding the mechanism and impact of collateral vessels on the Fontan circulation is important. Methods A 0-1-dimensional Fontan circulation hemodynamic model was developed to reproduce the hemodynamic changes of the blood flow in the entire body by introducing two types of collateral vessels (VVC: veno-venous collateral, APC: aorto-pulmonary collateral) into the model considering clinical status. Also, giving various conditions by ranging catecholamine dose and introducing the concept of oxygen delivery and consumption by changing workloads, arterial and central venous oxygen saturations (SaO2 and SvO2) are predicted in the Fontan circulation models. To evaluate the cardiac function, considering the impact of collateral vessels, four representative values were examined: (1) cardiac output (CO) per minute; (2) Ees relative to arterial elastance (Ees/Ea); (3) ejection fraction; and (4) the stroke work (SW) to pressure-volume area (PVA) ratio (SW/PVA). Results SaO2 and SvO2 were less in Fontan circulations with both VVC and APC present (92% and 54%) than those without collateral vessels (96% and 62%). Also, with collateral vessels, Ees/Ea was decreased while SW/PVA was increased, leading to poor perfusion to the tissue. Regardless of the presence or absence of collateral circulation, SaO2 and SvO2, and systemic blood flow rate decreased when pulmonary vascular resistance was high. By administering catecholamine at 10 microgram/kg/min, in the presence of both VVC and APC, SvO2 was increased from 53% to 58%, while SaO2 was decreased from 92% to 88%. Conclusions The simulated results of arterial and venous blood oxygen saturations and systemic blood flow rate were well-reproduced, matching the previously reported clinical results. It is suggested that pulmonary vasodilators may be beneficial in increasing blood oxygen saturation and improving tissue perfusion, even in Fontan patients with collateral vessels. However, the catecholamine's positive effect is limited. For reproducing various conditions of Fontan circulations, it is necessary to collect actual measurement data from a variety of patients and validate the predicted value to increase the credibility of the model.Arterial and venous oxygen saturationsPressure and volume curves

Moyamoya Angiopathy: An Underdiagnosed Cause of Ischemic Stroke in a Tunisian Pediatric Cohort

BackgroundMoyamoya angiopathy is a rare cerebral vasculopathy and an underdiagnosed cause of arterial ischemic stroke in children. We aim to report the clinical and radiological presentations in a Tunisian pediatric cohort. MethodsWe identified moyamoya angiopathy in pediatric patients managed at the Child Neurology Department of Hedi Chaker Sfax University Hospital between 2008 and 2020 and reviewed their clinical and radiological data as well as their evolutionary profile. ResultsWe collected 14 patients with median age 40.6 months and a female predominance (sex ratio of 0.75). An arterial ischemic stroke (AIS) revealed the disease in all patients, with the major symptom being a motor deficit. Symptoms related to a transient ischemic attack before the diagnostic consultation were reported in four patients. Carotid territory was, clinically and radiologically, the most frequently involved. Brain magnetic resonance imaging with angiography was performed in 12 patients confirming the diagnosis by revealing the development of collateral vessels. All the investigations concluded to moyamoya disease in 57.2% and moyamoya syndrome in 42.8%. The latter was related to Down syndrome in five patients and neurofibromatosis type 1 in one patient. With a mean follow-up of 2.35 years, two patients had at least two more AISs during the first two years following diagnosis and 42.8% of patients were diagnosed with vascular or poststroke epilepsy. Full recovery was noted in 14.3% of cases. ConclusionsMoyamoya angiopathy in children is a serious condition that needs to be recognized due to the high risk of recurrent ischemic strokes.

Effect of thin-split encephalomyosynangiosis on transient neurological events in revascularization surgery for pediatric patients with moyamoya disease.

Transient neurological events (TNEs) are among the most important events after revascularization surgery in pediatric patients with moyamoya disease (MMD). Although hemodynamic changes and crying are representative factors of TNEs, brain compression by encephalomyosynangiosis (EMS) is another important cause of TNEs. Therefore, the authors assumed that making the EMS as thin as possible reduces the frequency of TNEs. However, thin-split EMS can lead to insufficient development of collateral vessels. This study aimed to evaluate the effects of thin-split EMS in combined revascularization surgery on postoperative outcomes in pediatric patients with MMD. The authors retrospectively included 56 consecutive combined revascularization surgeries in the anterior cerebral circulation in pediatric patients with MMD. These surgeries were classified into the former group and thin-split EMS group. The temporal muscle was halved in the former EMS group and split as thinly as possible in the thin-split EMS group. The authors performed between-group comparisons of postoperative stroke events and TNEs during the acute period and the development of collateral flow and stroke events during the chronic period. Former and thin-split EMS procedures were performed in 37 and 19 patients, respectively. TNEs without crying or hemodynamic changes were observed significantly less frequently in the thin-split EMS group than in the former EMS group (0 [0.0%] in the thin-split EMS group vs 9 [24.3%] in the former EMS group, p = 0.021). There were no significant between-group differences in the development of indirect bypass during the chronic period (good: 34 [91.9%] and poor: 3 [8.1%] in the former EMS group vs good: 16 [84.2%] and poor: 3 [15.8%] in the thin-split EMS group; p = 0.397). Additionally, there were no significant between-group differences in the incidence of chronic clinical events, including death or stroke. Thin-split EMS can reduce TNEs that do not accompany crying or hemodynamic changes. Furthermore, the procedure has sufficient prevention effects against stroke events during the chronic postoperative period in pediatric patients with MMD.

Postoperative constrictive pericarditis caused rupture of lymphatic collaterals: a rare etiology of chylothorax

BackgroundChylothorax after cardiovascular surgery is primarily caused by direct injury to the thoracic duct or its branches, and occurs in early postoperative period. In the present case, we describe a rare case of chylothorax manifesting three months after surgery secondary to constrictive pericarditis.Case presentationA 71-year-old man underwent mitral valve replacement, tricuspid valve annuloplasty, and the maze procedure. He developed acute perioperative myocardial infarction on postoperative day one due to plaque rupture in the left anterior descending artery and underwent percutaneous coronary intervention. Although the patient was discharged on postoperative day 36, he required readmission on postoperative day 83 because of right side chylothorax associated with constrictive pericarditis. Lymphangiography revealed thoracic duct interruption and development of lymphatic collateral vessels via the right hilum. Single-photon emission computed tomography revealed abnormal tracer accumulation in the right hilum, suggesting a lymphatic leakage site. A catheter study indicated biventricular dip and plateau patterns with a reduced cardiac index (1.6 L/min/m2) and elevated central venous pressure (18 mmHg). Conservative treatment for chylothorax, including a low-fat diet and continuous drainage with chest tube, was unsuccessful. Drainage of chyle at approximately 500 mL/day continued. On hospitalization day 50, complete pericardiectomy via median sternotomy was performed because the patient’s cardiac function deteriorated. The central venous pressure dramatically decreased, and the chylothorax gradually subsided. There was no recurrence of symptoms 1 year postoperatively.ConclusionsChylothorax associated with constrictive pericarditis subsequent to cardiac surgery is extremely rare. Although conservative management failed, the present case was successfully treated via pericardiectomy alone and did not require any additional precedures, such as thoracic duct ligation via a right thoracotomy.

A new fasciocutaneous flap model identifies a critical role for endothelial Notch signaling in wound healing and flap survival

Flap surgery is a common treatment for severe wounds and a major determinant of surgical outcome. Flap survival and healing depends on adaptation of the local flap vasculature. Using a novel and defined model of fasciocutaneous flap surgery, we demonstrate that the Notch ligand Delta-like 1 (Dll1), expressed in vascular endothelial cells, regulates flap arteriogenesis, inflammation and flap survival. Utilizing the stereotyped anatomy of dorsal skin arteries, ligation of the major vascular pedicle induced strong collateral vessel development by end-to-end anastomosis in wildtype mice, which supported flap perfusion recovery over time. In mice with heterozygous deletion of Dll1, collateral vessel formation was strongly impaired, resulting in aberrant vascularization and subsequent necrosis of the tissue. Furthermore, Dll1 deficient mice showed severe inflammation in the flap dominated by monocytes and macrophages. This process is controlled by endothelial Dll1 in vivo, since the results were recapitulated in mice with endothelial-specific deletion of Dll1. Thus, our model provides a platform to study vascular adaptation to flap surgery and molecular and cellular regulators influencing flap healing and survival.

Enhanced external counter pulsation therapy in patients with symptomatic and severe intracranial steno-occlusive disease: a randomized clinical trial protocol.

ClinicalTrials.gov, Identifier: NCT03921827.

Abstract #1395609: Moyamoya Syndrome in a Patient with Thyroid Storm; Role of Plasmapheresis?

Moyamoya syndrome is a rare cerebrovascular disorder that can be associated with Graves’ disease. We are presenting a case of young woman with Graves’ disease who developed acute neurologic symptoms. She was treated with plasmapheresis and developed cerebral edema after one procedure. A 28-year-old Hispanic female with 3 years history of Graves’ disease presented to ER with worsening symptoms of thyrotoxicosis. She was not taking antithyroid medications for the previous months. She was admitted for severe hyperthyroidism symptoms. Antithyroid medication was resumed on admission. A day later she developed sudden weakness of the right upper and lower extremities, then she became unresponsive. TSH was < 0.007 uIU/mL [0.36-3.7 mIU/mL], free T4 >8.0 ng/dl [0.76-1.46 ng/dl], total T3 2.75 ng/mL [0.6-1.8 ng/mL]. Brain imaging demonstrated occlusion of the right and left internal carotid arteries consistent with the diagnosis of Moyamoya disease. Treatment for thyroid storm with Propylthiouracil and steroids were initiated. The patient’s mental status did not improve, and plasmapheresis was initiated to improve her symptoms and neurologic outcome. Patient was hemodynamically stable during plasmapheresis with no signs of fluid shift. Several hours after the 1st session, the patient neurologically deteriorated, pupils were fixed and dilated, and corneal reflex was negative. Repeated brain imaging showed cerebral herniation, which ultimately led to brain death. Moyamoya disease is an isolated vascular disorder and a rare cause of stroke. It involves endothelial hyperplasia and narrowing of the proximal portion of the internal carotid arteries, leading to development of abnormal collateral vessels. There are several studies correlating increased thyroid hormone and auto-antibody levels with Moyamoya disease. Therapeutic plasma exchange is used to achieve rapid improvement in symptoms due to the long half-life of thyroid hormones and to eliminate the autoantibodies. It is considered a safe procedure with low incidence of adverse events. However, in patients with severe comorbidities, especially those in the intensive care unit (ICU), the prevalence of adverse events during plasmapheresis is reported to be higher. In this case, no water imbalance was reported during the procedure, and it is unknown whether the plasmapheresis played a role in cerebral edema and herniation. In general, Plasmapheresis is considered a relatively safe for patients hospitalized in ICU in literature reviews, with no reports of cerebral edema as a complication of plasmapheresis in these literatures. However, close monitoring of patients in the ICU is essential for procedure-related safety.

Encephalo-Duro-Pericranio-Synangiosis for the Treatment of Moyamoya Disease with Posterior Cerebral Artery Lesions

We describe our experience performing encephalo-duro-pericranio synangiosis for the parieto-occipital region (EDPS-p) as a treatment for moyamoya disease (MMD) with hemodynamic disturbances caused by lesions of the posterior cerebral artery. From 2004 to 2020, 60 hemispheres of 50 patients with MMD (38/50 females, age 1-55 years) underwent EDPS-p as a treatment for hemodynamic disturbances in the parieto-occipital region. A skin incision was made on the parieto-occipital area to avoid the major skin arteries, and the pedicle flap was created by attaching the pericranium to the dura mater under the craniotomy with multiple small incisions. The surgical outcome was assessed on the basis of the following points: perioperative complications, postoperative improvement of clinical symptoms, subsequent novel ischemic events, qualitative assessment of the development of collateral vessels by magnetic resonance arteriography, quantitative assessment of postoperative perfusion improvement based on the mean transit time, and cerebral blood volume on dynamic susceptibility contrast imaging. Perioperative infarction occurred in 7/60 hemispheres (11.7%). The transient ischemic symptoms observed preoperatively disappeared in 39/41 hemispheres (95.1%) during the follow-up period (12-187 months), and none of the patients experienced novel ischemic events. Collateral vessels supplied from the occipital arteries, middle meningeal arteries, and posterior auricular arteries developed postoperatively in 56/60 hemispheres (93.3%). Postoperative mean transit time and cerebral blood volume showed significant improvement in the occipital, parietal, and temporal areas (P < 0.001), as well as the frontal area (P= 0.01). EDPS-p seems to be an effective surgical treatment for patients with MMD who suffer hemodynamic disturbances caused by posterior cerebral artery lesions.

Abstract WP101: Vessel Wall Enhancement Is Associated With Symptomatic Adult Moyamoya Disease And Syndrome In An American Population

Introduction: Moyamoya Disease (MMD) and Moyamoya Syndrome (MMS) are chronic progressive cerebrovascular disease characterized by bilateral or unilateral stenotic arteries around the circle of Willis with subsequent development of collateral blood vessels. MMS is associated with conditions such as Down Syndrome (DS) or sickle cell disease (SCD). The presence of vessel wall enhancement (VWE) on high resolution magnetic resonance vessel wall imaging (HR MR VWI) in MMD or MMS is controversial. Recent studies suggest VWE is associated with recent ischemic or hemorrhagic stroke. The significance of VWE in MMD or MMS in non-Asian population has not been well established. Our study aimed to investigate the prevalence of VWE in adult MMD/MMS in the United States and identify its predictive value for stenosis progression. Methods: We retrospectively reviewed patients with MMD or MMS admitted to Clements University Hospital and Parkland Memorial Hospital affiliated with University of Texas Southwestern Medical Center from January 2014 to March 2022. Patients were included if HR MR VWI was performed during workup. Patients were excluded if intracranial atherosclerosis was the suspected stroke etiology from cardiovascular risk factors. The presence of the VWE on HR MR VWI and stenosis grading were evaluated by blinded neuroradiologists and vascular neurologists. Symptomatic disease was defined as ischemic stroke, hemorrhagic stroke or transient ischemic attack within 24 months before HR MR VWI was obtained. Results: A total of 32 patients were included, of which 28 had MMD, 3 had MMS from SCD and 1 had MMS from DS. Mean age at diagnosis was 34 ± 10 years old, and 29 (90.6%) were female. VWE was seen in 22 (68.8%) patients. VWE is more common in symptomatic disease than asymptomatic disease (95% vs 20%). 24 patients had follow up MR angiogram with average time from HR MR VWI of 25.8 ± 16.7 months. Among 12 patients with 16 non-occlusive arteries, stenosis progression was seen in 67% of arteries with VWE compared to 25% of arteries without VWE. Conclusions: In a North American population with MMD or MMS, VWE on HR MR VWI was more common in symptomatic disease. The presence of VWE was associated with increased risk of stenosis progression. More studies are needed to confirm these findings.

Predictive factors of collateral vessel development induced by oxaliplatin-based chemotherapy.

Oxaliplatin can lead to hepatic sinusoidal injury, called hepatic sinusoidal obstruction syndrome (SOS), resulting in portal hypertension-related complications. This could worsen the clinical course of the patients treated with oxaliplatin. Early diagnosis is challenging. We explored predictive markers of oxaliplatin-induced collateral vessels. Patients who received oxaliplatin-based chemotherapy were retrospectively screened. We evaluated their laboratory findings and spleen size on computed tomography immediately before oxaliplatin-based chemotherapy and after 6months of treatment. The primary outcome was collateral vessel development, as a surrogate marker for oxaliplatin-induced SOS in patients who underwent oxaliplatin-based chemotherapy. The secondary outcome was the identification of factors that predicted the development of collateral vessels. We enrolled 161 patients who received oxaliplatin-based chemotherapy. They had a median age of 69years, and 63.3% were men. Collateral vessels developed in nine (5.6%) patients during the study period. After oxaliplatin-based chemotherapy, the spleen size increased in 104 patients (64.6%), with a ≥ 30% increase in 19.4% of the patients. Univariate analysis showed that the Fibrosis-4 (FIB-4) index (≥ 1.76; OR 9.17), aspartate aminotransferase:platelet ratio index (APRI) (≥ 0.193; OR 9.62), cumulative dose of oxaliplatin (≥ 1000mg; OR 8.43), and increase in spleen size (≥ 30%; OR 6.01) were significant risk factors for collateral vessel development. Multivariate analysis after stepwise selection revealed that the FIB-4 index and spleen size were significant independent predictive factors. A ≥ 1.76 increase in the FIB-4 index and a ≥ 30% increase in spleen size after 6months of oxaliplatin-based chemotherapy were significant predictive markers for collateral vessel development.

СОВРЕМЕННЫЕ ПОДХОДЫ К ЛЕЧЕНИЮ РЕТИНАЛЬНЫХ ОККЛЮЗИЙ ВЕН СЕТЧАТКИ, ЛИТЕРАТУРНЫЙ ОБЗОР

Retinal vein occlusion (RVO) is the second among acquired vascular eye diseases, giving priority only to diabetic retinopathy. The severity of retinopathy depends on the location of the occlusion and the development of collateral vessels. RVO is not accompanied only by a decrease in visual acuity (VA), but also by the development of such complications as recurrent intravitreal hemorrhages, traction retinal detachment, secondary neovascular glaucoma. It causes the disability of patients and loss of professional fitness in people of working age. The treatment of RVO focuses on two main goals. The first one is the identification of risk factors and their drug therapy, and the second one is the identification and treatment of complications of retinal vein occlusion. The treatment of any pathology depends on early diagnosis, as well as a quick and well-chosen algorithm for managing the patient. The macular edema is treated by intravitreal injections of corticosteroids, antiVEGF, laser photocoagulation of the retina. Intraocular injections is currently the only way to provide a high intravitreal and intraretinal concentration of the drug. This review describes an algorithm for choosing the optimal treatment for RVO.