Cerebral Hyperperfusion Syndrome Research Articles

Risk Factors for Cerebral Hyperperfusion Syndrome After Combined Revascularization in Adult Patients with Moyamoya Disease.

Cerebral hyperperfusion syndrome (CHS) is known as a complication after bypass surgery for Moyamoya disease (MMD). However, the incidence of CHS has not been accurately reported, and there is no consensus on the risk factors associated with it. The aim of this study was to determine the risk factors associated with postoperative CHS after surgical combined revascularization used to treat adult patients with MMD. To assess the frequency and characteristics of CHS in patients with MMD after revascularization operations. Patients who received combined revascularization from Jan 2021 to Nov 2022 were retrospectively reviewed. Preoperative clinical characteristics and radiographic features were recorded. Postoperative CHS after surgery were examined. Multivariate logistic regression analyses were performed to identify the risk factors for CHS. A total of 133 patients (141 hemispheres) were included in this study. Postoperative CHS were observed in 28 hemispheres (19.8%), including focal cerebral hyperperfusion syndrome (FCHS) in 20 hemispheres (14.2%), hemorrhage in 4 (4.4%) hemispheres, seizures in 4 (4.4%) hemispheres. The results of multivariate logistic regression analysis indicated that preoperative hypertension (OR 3.940, 95% CI 1.275 ~ 12.180, p = 0.017), cerebral hemorrhage onset (OR 5.489, 95% CI 1.443 ~ 20.884, p = 0.013) and higher Hct level (OR 1.166, 95% CI 1.047 ~ 1.298, p = 0.005) were significantly associated with CHS after combined revascularization. Preoperative hypertension, cerebral hemorrhage onset, and higher Hct level were independent risk factors for CHS after combined revascularization.

Neurosonological Parameters May Predict the Risk of Cerebral Hyperperfusion Syndrome After Carotid Artery Stenting

Cerebral hyperperfusion syndrome (CHS) is a critical complicationin patients underwent carotid artery stenting (CAS). We sought to explore neurosonological parameters and additional risk factors associated with CHS in patients following CAS and further to develop a prediction model for CHS after CAS. A total of 197 patients who underwent CAS were included in this observational study. All patients were divided into CHS and non-CHS groups. Demographic, clinical, treatment, and laboratory data were extracted from electronic medical records. Logistic regression analysis and nomogram listing were used to build a CHS prediction model. Machine learning algorithms with five-fold cross-validation were used to further validate the CHS prediction model. Twenty-two patients had clinically manifested CHS. Four parameters were detected as risk factors associated with CHS, including effective collateral circulation (ECC) (p = 0.046), asymmetry ratio of peak systolic velocity of the middle cerebral artery (ARP) (p = 0.001), severe stenosis or occlusion of the contralateral carotid artery (p = 0.010), and low-density lipoprotein cholesterol (LDL-C) (P = 0.025). The area under the curve for the prediction model of CHS in the cohort was 0.835 (95% CI 0.760-0.909). In this study, CHS following CAS was associated with ECC, ARP, contralateral ICA severe stenosis or occlusion, as well as LDL-C. Subsequently, the CHS prediction model for CAS was built, which has the potential to facilitate tailored and precise management as well as treatment strategies for patients at high risk of CHS.

ST-elevation myocardial infarction in patients with type 2 diabetes mellitus. Influence of the SGLT2 inhibitor dapagliflozin

Background. Patients with type 2 diabetes mellitus (T2DM) have a 2-fold higher risk of deve­loping coronary heart disease and mortality than those without carbohydrate metabolism disturbances. The reason for such negative trends is the occurrence of metabolic stress due to hyperglycemia and insulin resistance, which causes disturbance in energy metabolism and ischemic damage to cardiomyocytes. The purpose of the study is to improve the effectiveness of rehabilitation treatment and assess the dynamics of quality of life in patients with ST-elevation myocardial infarction (STEMI) and T2DM who are at high risk of develo­ping cardiac complications during the inpatient treatment by including the sodium-glucose transport protein 2 (SGLT2) inhibitor dapagliflozin in the comprehensive therapy. Materials and methods. The study group consisted of 38 patients with STEMI and T2DM who received dapagliflozin in addition to percutaneous coronary intervention (PCI). The control group included 37 patients with STEMI and T2DM who received only standard protocol treatment after PCI. In addition to general clinical examinations and assessment of quality of life using the EuroQol Group EQ-5D-5L questionnaire (1990), echocardiography was performed to determine general and local myocardial contractility by the Simpson method; plasma levels of glucose, insulin were evaluated, and insulin resistance was determined by the HOMA-IR. Results. Patients with STEMI and T2DM after PCI most often developed reperfusion syndrome with left ventricular failure and rhythm disturbances. Under the influence of standard medical treatment, a significant clinical and functional improvement was observed, but postinfarction remodeling progressed with impaired systolic and diastolic function and the development of heart failure syndrome, as well as treatment-resistant atrial and ventricular fibrillation paroxysms, supraventricular and ventricular extrasystoles, and bundle branch block. In patients of the study group with STEMI and T2DM on the comprehensive treatment with the SGLT2 inhibitor dapagliflozin, a significant decrease in the frequency of rhythm and conduction disturbances was noted on the se­cond day of observation, as well as a decrease in postinfarction left ventricular remodeling, which ultimately manifested in a statistically significant improvement of myocardial contractility (ejection fraction increased by 6.7 %) and a decrease in diastolic dysfunction. There was also a significant decrease in the frequency and severity of reperfusion arrhythmias, which was achieved due to the cardiometabolic effect of the SGLT2 inhibitor dapagliflozin. Conclusions. The inclusion of the SGLT2 inhibitor dapagliflozin in the comprehensive treatment led to a significant improvement in central cardiac hemodynamic parameters and a decrease in the frequency and severity of reperfusion arrhythmias and acute left ventricular failure, which contributed to the improvement in quality of life.

Uncommon Carotid Artery Stenting Complications: A Series by Images.

To describe through emblematic images rare but clinically relevant carotid artery stenting complications that occurred at two high-volume centres for carotid artery stenting (CAS). CAS is an alternative to carotid endarterectomy (CEA) for the treatment of carotid artery stenosis in patients judged to be at high risk for CEA. CAS complications range between 1 and 9% and are higher in older patients complaining of neurological symptoms at the time of presentation. Besides periprocedural or early-after-procedure stroke, which remains the true Achilles' heel of CAS, other dramatic complications might compromise the clinical outcomes of this procedure. Five infrequent complications, out of more than 1000 CAS performed in the years 2016-2021, have been described. Among CAS complications, acute carotid stent thrombosis, rescue retrieval of a disconnected distal cerebral embolic protection device, plaque prolapse after carotid stenting, cerebral hyperperfusion syndrome (CHS), and radial artery long sheath entrapment requiring surgical intervention were found to account for 0.3% of the total number of procedures performed by operators with high CAS volume. Unusual CAS complications may infrequently occur, even in hands of expert operators. To know how to deal with such complications might help interventionalists to improve CAS performance.

Crossed Cerebellar Diaschisis and Cerebral Infarction After Cerebral Hyperperfusion Syndrome Following Carotid Artery Stenting: A Case Report

Crossed cerebellar diaschisis (CCD) often occurs after ischemic or hemorrhagic stroke that does great damage to the cortico-ponto-cerebellar pathway (CPCP). Nevertheless, as far as we know, CCD due to cerebral hyperperfusion syndrome (CHS) following carotid artery stenting (CAS) is rare. We report a case where CCD and new cerebral infarction after CHS following CAS was effectively treated by intravenous use of edaravone and mannitol. The patient was a 74-year-old female. She developed dizziness and vomiting accompanied with weakness of the right limb for 8 days and was admitted to our hospital. Computed tomography angiography scan revealed severe stenosis at the beginning of the left internal carotid artery. Further digital subtraction angiography (DSA) revealed severe stenosis at the beginning of the left internal carotid artery, with a stenosis rate of approximately 90%. Therefore, she underwent left CAS implantation. After the operation, the patient developed disturbance of consciousness and decreased muscle strength in the right limb. Intravenous infusion of edaravone and mannitol were then started. After 10 days of medical treatment, the condition of patient improved to mild hemiparesis. The findings in this present case strongly suggest that CHS after CAS for carotid artery stenosis may cause transient CCD.

Circulatory support with venovenous ECMO in a patient with reperfusion pulmonary edema after pulmonary artery thromboendarterectomy

Chronic thromboembolic pulmonary hypertension (CTEPH) is a subtype of pulmonary hypertension characterized by the obstruction of pulmonary arteries secondary to chronic thromboembolism. Pulmonary thromboendarterectomy surgery (PTE) is the main treatment for patients with CTEPH, as it removes the chronic thrombi from the pulmonary arteries. Pulmonary reperfusion syndrome is a common complication of the surgery, which involves the development of pulmonary edema in the area where blood perfusion improves after the surgery. The incidence of this syndrome varies from 8 to 91% depending on the criteria used for diagnosis, and it is one of the most serious complications of pulmonary thromboendarterectomy. In such cases, circulatory support with extracorporeal membrane oxygenation (ECMO) has become a valuable therapeutic modality. We present the case of a 60-year-old woman with a history of acute pulmonary embolism due to deep vein thrombosis of the right pelvic limb who was diagnosed later with CTEPH who was admitted for scheduled surgical treatment involving bilateral PTE. However, during the immediate postoperative period, she developed cardiogenic shock and refractory hypoxemia secondary to pulmonary reperfusion syndrome following the surgical procedure. As a result, she required veno-venous ECMO circulatory support for 6 days, leading to resolution of the pulmonary condition and clinical improvement.

The effects of anastomoses between anterior and posterior circulation on postoperative prognosis of patients with moyamoya disease.

Moyamoya disease (MMD) is a chronic ischemic cerebrovascular disease. Collateral circulation in MMD has emerged as a research focus. Our aims were to assess the impact of anastomoses between the anterior and posterior circulations on the prognosis of MMD patients. We reviewed the preoperative digital subtraction angiography images of patients with MMD who underwent revascularization surgery at our hospital between March 2014 and May 2020 and divided the patients into two groups: those with anastomoses (PtoA group) and those without anastomoses (non-PtoA group). The differences in follow-up (more than 6months) collateral vessel establishment (Matsushima grade) and the modified Rankin Scale (mRS) were compared between the two groups as well as between the patients with different degrees of anastomoses. The early complications following revascularization were also compared between the two groups. This study included 104 patients with MMD, of which 38 were non-PtoA and 66 were PtoA. There were no significant differences in Matsushima score (P = 0.252) and mRS score (P = 0.066) between the two groups. In addition, Matsushima score (P = 0.243) and mRS score (P = 0.360) did not differ significantly between patients with different degrees of anastomoses. However, the non-PtoA group had a significantly higher rate of cerebral hyperperfusion syndrome (CHS) than the PtoA group (34.2% vs 16.7%, P = 0.041). MMD patients without anastomoses between anterior and posterior circulations preoperatively should be vigilant of the occurrence of CHS in the early stages after revascularization.

Reperfusion Injury—Post-Endovascular Recanalization in Chronic Mesenteric Ischemia: A Rare Clinical Case Scenario

AbstractRegardless of the number of vessels involved endovascular recanalization of mesenteric vessels is the treatment of choice for chronic mesenteric ischemia. Reperfusion injury post-endovascular recanalization in chronic mesenteric ischemia is a rare clinical scenario as it is mostly encountered in cases of acute mesenteric ischemia. Here in, we describe a case with characteristic clinical and imaging findings of reperfusion syndrome, post-endovascular recanalization of chronically occluded superior mesenteric artery and severely stenosed celiac trunk in a patient with chronic mesenteric ischemia.

Hypothermic oxygenated perfusion in liver transplantation: a meta-analysis of randomized controlled trials and matched studies.

Hypothermic oxygenated machine perfusion (HOPE) is a novel organ-preservation technology designed to optimize organ quality. However, the effects of HOPE on morbidity and mortality after liver transplantation remain unclear. This meta-analysis evaluated the potential benefits of HOPE in liver transplantation. The Embase, Web of Science, PubMed, Cochrane Library, and Scopus databases were searched for articles published up to 15 June 2023 (updated on 12 August 2023). Mean differences (MDs), risk ratios (RRs), and 95% confidence intervals were calculated. Eleven studies encompassing five randomized controlled trials and six matched studies were included, with a total of 1000 patients. HOPE did not reduce the incidence of major postoperative complications (RR 0.80), primary non-function (PNF) (RR 0.54), reperfusion syndrome (RR 0.92), hepatic artery thrombosis (RR 0.92), renal replacement therapy (RR 0.98), length of hospital stay (MD, -1.38 days), 1-year recipient death (RR 0.67), or intensive care unit stay (MD, 0.19 days) after liver transplantation. HOPE reduced the incidence of biliary complications (RR 0.74), non-anastomotic biliary strictures (NAS) (RR 0.34), early allograft dysfunction (EAD) (RR 0.54), and acute rejection (RR 0.54). In addition, HOPE improved the retransplantation (RR 0.42) and 1-year graft loss rates (RR 0.38). Compared with static cold storage (SCS), HOPE can reduce the incidence of biliary complications, NAS, EAD, and acute rejection and retransplantation rate after liver transplantation and improve the 1-year graft loss rate. These findings suggest that HOPE, when compared to SCS, can contribute to minimizing complications and enhancing graft survival in liver transplantation. Further research is needed to investigate long-term outcomes and confirm the promising advantages of HOPE in liver transplantation settings.

A USAGE OF THE IMPEDANCE METHOD FOR DETECTING CIRCULATORY DISORDERS TO DETERMINE THE DEGREE OF LIMB ISCHEMIA

New engineering technologies allow the creation of diagnostic devices for predicting the development of acute tissue ischemia of the extremities and determining the residual time until the removal of the tourniquet, and solving these tasks is particularly relevant during military actions. Acute limb ischemia is a sudden critical decrease in perfusion that threatens the viability of the limb. The incidence of this condition is 1.5 cases per 10 000 people per year. Acute ischemia occurs due to the blockage of blood flow in major arteries (embolism, thrombosis, trauma), leading to the cessation of adequate blood supply to metabolically active tissues of the limb, including the skin, muscles, and nerve endings. To address these issues, the article analyzes the changes in the impedance of biological tissue. The introduction and use of the coefficient of relative electrical conductivity, denoted as k, as a diagnostic criterion parameter, are justified. Experimental studies of changes in the coefficient of relative electrical conductivity k were conducted, confirming that the transition from exponential to linear dependencies of the coefficient establishes the degree of viability of the biological cell (tissue) and the moment of occurrence of reperfusion syndrome. It has been established that a deviation of the value of k by 10–15% from its unit value diagnoses the initial process of blood perfusion impairment and the development of ischemic tissue disease. The rate of change of k serves as a criterion for predicting the progression of the disease and as a corrective factor for therapeutic treatment.

Comparison of the results of open vascular surgery interventions in patients with arterial injury caused by penetrating trauma below the knee in the Vascular Surgery Center of Golestan Ahvaz Hospital

Vascular damage is one of the life-threatening emergency situations and is considered one of the most common causes of death worldwide. Considering the frequency of penetrating vascular injuries, especially in our country and Khuzestan province, as well as complications and mortality caused by vascular injuries, this study was designed to investigate the effect of vascular surgery intervention on patients with arterial trauma trauma below the knee. Method: In this descriptive and analytical study, all trauma patients suspected of penetrating arterial injuries below the knee in terms of parameters of age, gender, type of trauma, location of trauma, type of intervention, location of arterial repair, angiographic and clinical findings including damaged arteries, type of injury Arterials were also examined for the presence of fracture or dislocation in the vicinity of vascular damage. Results: The results of this study showed that among the penetrating trauma patients requiring surgical intervention, 89.1% were men and only 10.9% were women. The average age of the patients was 35 years. The most frequent trauma requiring surgical intervention in this study was the trauma caused by firearms (gunshot and shotgun) and the least urban and occupational trauma. There was a significant relationship between trauma. The highest rate of injury was to the popliteal artery below the knee (8.47%), and the most vascular intervention was saphenous vein entrapment. 9.73% of the patients had a fracture injury and 3.16% had a dislocation with vascular injury. Conclusion: According to the results of the present study, the association of vascular injuries with orthopedic fractures was higher and mostly in the popliteal region. Complications including infection, fasciotomy, reperfusion syndrome and amputation have a direct and significant relationship with the type of penetrating trauma.

The impact of conduction anesthesia at the hemostastic system in the limb reperfusion syndrome in pediatric traumatology-orthopedic practice

Introduction. Activation of the hemostatic system in the ischemia-reperfusion syndrome is a risk factor for thromboembolic complications during orthopedic surgical interventions associated with arterial tourniquet application. Therefore, it is relevant to find ways to mitigate reperfusion effects during such surgeries.
 Purpose. To find out character and effects of conduction anesthesia at the thromboelastogram parameters in the ischemic limb reperfusion after removing a tourniquet during orthopedic surgeries in children.
 Material and methods. The surgery which was performed in 20 patients from the traumatologic department in the City Children’s Clinical Emergency Hospital (Novosibirsk) required arterial tourniquet application. So, these patients were enrolled in the observational pilot study. The patients who had tourniquet application were distributed into two groups by the block randomization: Group 1 (n=10) – peripheric blockage; Group 2 (n=10) – no peripheric blockage. The basic technique used in the study was thromboelastography (TEG) with TEG5000 thromboelastograph (Haemonetics Corporation, USA). All patients had thromboelastography before tourniquet application (stage 1) and 5 minutes after its removal (stage 2). Main thromboelastogram parameters were assessed: R, measuring pathways for coagulation phases I and II; K – time, characterizing coagulation phase III; angle α, duplicating the information of “K” indicator; MA is the maximum amplitude of TEG branch divergence, characterizing the clot density which, in turn, depends on the function of platelet activity and on the amount of fibrinogen; LY30 is the percentage of clot lysed in 30 minutes.
 Results. In the group with regional anesthesia, indicators R, K, angle α, MA did not change at stage II; LY30 index decreased at stage 2. In the group without regional anesthesia, but with powerful central analgesic, indicators R, K, MA decreased, and angle α and LY30 increased at stage 2.
 Conclusion. In pediatric orthopedic surgeries with arterial tourniquet application , local anesthetic (Ropivacaine) in the conduction anesthesia technique prevented activation of the hemostastic system.

Combination of intraoperative indocyanine green video-angiography FLOW 800 and computed tomography perfusion to assess the risk of cerebral hyperperfusion syndrome in chronic internal carotid artery occlusion patients after revascularization surgery.

To study the changes of corticocerebral hemodynamics in surgical area and postoperative hyperperfusion syndrome in patients with chronic internal carotid artery occlusion (CICAO) by intraoperative indocyanine green videoangiography (ICGA)-FLOW 800 and CT perfusion after superficial temporal artery (STA)-middle cerebral artery (MCA) bypass surgery. From October 2019 to January 2021, 77 patients diagnosed with CICAO underwent direct bypass surgery at Huadong hospital (affiliated with Fudan University) were enrolled. Regions of interest (ROIs) at STA, proximal MCA (PMCA), distal MCA (DMCA), cortical blood capillary (CBC), and cortical vein (CV) were identified after anastomosis by ICGV-FLOW 800 including peak fluorescence intensity (PFI), time to peak (TTP), and area under the time curve (AUC) of fluorescence intensity. All patients underwent perfusion-weighted CT before bypass surgery and those patients with HPS were verified by CTP after bypass. 14 patients with HPS were verified by perfusion-weighted CT after bypass. In HPS group, the AUCTTP of DMCA was significantly larger (T = -3.301, p = 0.004) and TTP of CBC was shorter (T = -2.929, p = 0.005) than patients in non-HPS group. The larger AUCTTP of DMCA (OR = 3.024, 95%CI 1.390-6.578, p = 0.0050) was an independent risk factor by further multivariate logistic regression analysis. The hemodynamic changes of cortical vessels during STA-MCA bypass surgery could be recorded accurately by ICGV-FLOW 800. Furthermore, the increased AUCTTP of DMCA and shorter TTP of CBC may be potential risk factors of HPS.

The incidence of prolonged stay in ICU due to the development of reperfusion syndrome after carotid endarterectomy – five year analisis from University Clinical Center of Banjaluka

The incidence of prolonged stay in ICU due to the development of reperfusion syndrome after carotid endarterectomy – five year analisis from University Clinical Center of Banjaluka

Dynamic Cerebral Autoregulation After Carotid Endarterectomy.

Studies have shown that dynamic cerebral autoregulation (dCA) is impaired in patients with severe internal carotid artery (ICA) stenosis and that carotid endarterectomy (CEA) may improve dCA in these patients. However, the time course of dCA changes in patients after CEA remains unclear. Therefore, this study aimed to investigate the effects of CEA on the dCA in patients with carotid artery stenosis at different time points. This prospective study enrolled 44 patients (19 symptomatic stenosis patients and 25 asymptomatic stenosis patients) who underwent CEA and 44 age- and sex-matched controls. In the CEA group, the patients underwent dCA measurements at baseline, within 3 days, and 1 month after CEA. Transfer function parameters, phase difference (PD), and gain were used to quantify dCA. Changes in dCA before and after CEA were analyzed in detail. The bilateral PD of the patients before CEA was significantly lower than that of the control group. This damage did not improve within 3 days after surgery. One month after surgery, the PD on the affected side of the patients significantly improved compared with before surgery and reached the level of the control group. The PD of affected side across time points in symptomatic and asymptomatic stenosis patients is consistent with that in all patients. The dCA level did not improve immediately after CEA but significantly improved 1 month after surgery. This suggests that the occurrence of stroke should be considered in the acute period after CEA surgery, and its preventive effect on stroke may be effective after 1 month. We found the dCA level did not improve immediately after CEA but significantly improved 1 month after surgury. This suggests that the occuttencce of stroke and surgical complications (such as cerebral hyperperfusion syndrome) associated with impaired dCA in the acute phase after CEA surgery should be of particular concern.

Early Detection of hyperemia with Magnetic Resonance Fluid Attenuation Inversion Recovery Imaging after Superficial Temporal Artery to Middle Cerebral Artery Anastomosis.

Cerebral hyperperfusion syndrome(CHS) manifests as a collection of symptoms brought on by heightened focal cerebral blood flow, afflicting nearly 30% of patients who have undergone superficial temporal artery(STA)-middle cerebral artery(MCA) anastomosis. The aim of this study was to investigate whether the amalgamation of magnetic resonance imaging(MRI) fluid-attenuated inversion recovery(FLAIR) and apparent diffusion coefficient(ADC) imaging via MRI can discern cerebral hyperemia after STA-MCA anastomosis surgery. A retrospective study was performed of patients who underwent STA-MCA anastomosis due to Moyamoya disease or atherosclerotic steno-occlusive disease. A protocol aimed at preventing CHS was instituted, leveraging the use of MRI FLAIR. Patients underwent MRI diffusion with FLAIR imaging 24 h after STA-MCA anastomosis. A high signal on FLAIR images signified the presence of hyperemia at the bypass site, triggering a protocol of hyperemia care. All patients underwent hemodynamic evaluations, including perfusion MRI, single-photon emission computed tomography(SPECT), and digital subtraction angiography, both before and after the surgery. If a high signal intensity is observed on MRI FLAIR within 24 hours of the surgery, a repeat MRI is performed to confirm the presence of hyperemia. Patients with confirmed hyperemia are managed according to a protocol aimed at preventing further progression. Out of a total of 162 patients, 24 individuals(comprising 16 women and 8 men) exhibited hyperemia on their MRI FLAIR scans following the procedure. SPECT was conducted on 23 patients, and 11 of them yielded positive results. All 24 patients underwent perfusion MRI, but 9 of them showed no significant findings. Among the patients, 10 displayed elevations in both cerebral blood flow(CBF) and cerebral blood volume(CBV), 3 only showed elevation in CBF, and 2 only showed elevation in CBV. Follow-up MRI FLAIR scans conducted 6 months later on these patients revealed complete normalization of the previously observed high signal intensity, with no evidence of ischemic injury. The study determined that the use of MRI FLAIR and ADC mapping is a competent means of early detection of hyperemia after STA-MCA anastomosis surgery. The protocol established can be adopted by other neurosurgical institutions to enhance patient outcomes and mitigate the hazard of permanent cerebral injury caused by cerebral hyperemia.

Arterialized Vein Immediately After Direct Bypass Surgery Indicates Cerebral Hyperperfusion Syndrome in Moyamoya Disease.

Arterialized Vein Immediately After Direct Bypass Surgery Indicates Cerebral Hyperperfusion Syndrome in Moyamoya Disease.

Blood-brain barrier disruption imaging in postoperative cerebral hyperperfusion syndrome using DCE-MRI

Little has been reported about the association between cerebral hyperperfusion syndrome (CHS) and blood-brain barrier (BBB) disruption in human. We aimed to investigate the changes in permeability after bypass surgery in cerebrovascular steno-occlusive diseases using dynamic contrast-enhanced MRI (DCE-MRI) and to demonstrate the association between CHS and BBB disruption. This retrospective study included 36 patients (21 hemispheres in 18 CHS patients and 20 hemispheres in 18 controls) who underwent combined bypass surgery for moyamoya and atherosclerotic steno-occlusive diseases. DCE-MRI and arterial spin labeling perfusion-weighted imaging (ASL-PWI) were obtained at the baseline, postoperative state, and discharge. Perfusion and permeability parameters were calculated at the MCA territory (CBF(territorial), Ktrans(territorial), Vp(territorial)) and focal perianastomotic area (CBF(focal), Ktrans(focal), Vp(focal)) of operated hemispheres. As compared with the baseline, both CBF(territorial) and CBF(focal) increased in the postoperative period and decreased at discharge, corresponding well to symptoms in the CHS group. Vp(focal) was lower in the postoperative period and at discharge, as compared with the baseline. In the control group, no parameters significantly differed among the three points. In conclusion, Vp at the focal perianastomotic area significantly decreased in patients with CHS during the postoperative period. BBB disruption may be implicated in the development of CHS after bypass surgery.

The value of indocyanine green-FLOW800 in microvasculature for predicting cerebral hyperperfusion syndrome in moyamoya disease patients

Among the notable complications of direct hemodynamic reconstruction for moyamoya disease (MMD) is cerebral hyperperfusion syndrome (CHS). In this study, we evaluated hemodynamic changes in small regional microvasculature (SRMV) around the anastomosis site by using indocyanine green (ICG)-FLOW800 video angiography and verified that it better predicted the onset of CHS. Intraoperative ICG-FLOW800 analysis was performed on 31 patients (36 cerebral hemispheres) with MMD who underwent superficial temporal artery-middle cerebral artery (MCA) bypass grafting at our institution. The regions of interest were established in the SRMV and thicker MCA around the anastomosis. Calculations were made for half-peak to time (TTP1/2), cerebral blood volume (CBV), and cerebral blood flow (CBF). According to the presence or absence of CHS after surgery, CHS and non-CHS groups of patients were separated. The results showed that ΔCBV and ΔCBF were substantially greater in SRMV than in MCA (p < 0.001). Compared with the non-CHS group, ΔCBF and ΔCBV of SRMV and MCA were considerably greater in the CHS group (p < 0.001). ΔCBF and ΔCBV on the ROC curve for both SRMV and MCA had high sensitivity and specificity (SRMV: ΔCBF, AUC = 0.8586; ΔCBV, AUC = 0.8158. MCA: ΔCBF, AUC = 0.7993; ΔCBV, AUC = 0.8684). ICG-FLOW800 video angiography verified the differential hemodynamic changes in the peri-anastomotic MCA and SRMV before and after bypass surgery in patients with MMD.

Clinical effect of a modified superficial temporal artery-middle cerebral artery bypass surgery in Moyamoya disease treatment

BackgroundCerebral extracranial-intracranial (EC-IC) revascularization technique (superficial temporal artery-middle cerebral artery (STA-MCA) bypass grafting) has become the preferred surgical method for the treatment of Moyamoya disease (MMD). We attempted to completely free the two branches of the superficial temporal artery without disconnection. Extracranial and intracranial blood flow reconstruction were then modified by selectively performing a direct bypass technique on one branch and a patch fusion technique on the other of the STA based on the blood flow and the vascular diameter of the intracranial surface blood vessels.MethodsA series of modified STA-MCA bypass surgeries performed consecutively between March 2022 and March 2023 were reviewed and compared to conventional combined bypass surgeries performed during the same period. The following information was collected from all enrolled patients: demographic characteristics, clinical symptoms, and preoperative and postoperative imaging, including Suzuki stage and Matsushima grade. The modified Rankin scale (mRS) was used to assess the changes in neurological status before and after surgery.ResultsA total of 41 patients with Moyamoya disease (MMD) who underwent cerebral revascularization were included in this study, of which 30 were conventional revascularization and 11 were modified revascularization. The mean age was 49.91 years, and 18 (43.9%) of the patients were women. The modified group had a lower incidence of cerebral hyperperfusion syndrome (18.2%) than the conventional group (23.3%). After at least 3 months of follow-up, the bypass patency rate remained 100% in the modified group and 93.3% in the conventional group. All patients in the modified group achieved a better Matsushima grade (A + B), with six (54.5%) having an A and five (45.5%) having a B. In contrast, four patients (13.3%) in the conventional group had a Matsushima grade of C. In all, 72.8% of the modified group had postoperative mRS scores of 0 and 1, which was higher than that of the traditional group (63.3%).ConclusionThe improved STA-MCA bypass could provide blood flow to multiple cerebral ischemic areas, reduce excessive blood perfusion, and ensure blood supply to the scalp, with lower complications and better clinical benefits than the traditional combined bypass.