UNASSIGNED: Cerebral hyperperfusion syndrome (CHS), characterized by neurologic deficits due to postoperative high cerebral perfusion, is a serious complication of superficial temporal artery-middle cerebral artery (STA-MCA) surgery for moyamoya disease (MMD).
UNASSIGNED: We aim to clarify the importance of assessing pre-anastomosis cerebral microcirculation levels by linking the onset of CHS to pre- and post-anastomosis hemodynamics.
UNASSIGNED: Intraoperative laser speckle contrast imaging (LSCI) measured changes in regional cerebral blood flow (rCBF) and regional blood flow structuring (rBFS) within the cerebral cortical microcirculation of 48 adults with MMD.
UNASSIGNED: Following anastomosis, all MMD patients exhibited a significant increase in rCBF ( 279.60 % ± 120.00 % , p < 0.001 ). Changes in rCBF and rBFS showed a negative correlation with their respective baseline levels (rCBF, p < 0.001 ; rBFS, p = 0.005 ). Baseline rCBF differed significantly between CHS and non-CHS groups ( p = 0.0049 ). The areas under the receiver operating characteristic (ROC) curve for baseline rCBF was 0.753. Hemorrhagic MMD patients showed higher baseline rCBF than ischemic patients ( p = 0.036 ), with a marked correlation between pre- and post-anastomosis rCBF in hemorrhagic cases ( p = 0.003 ), whereas ischemic MMD patients did not.
UNASSIGNED: Patients with low levels of pre-anastomosis baseline CBF induce a dramatic increase in post-anastomosis and show a high risk of postoperative CHS.

暂无摘要。

Minor non-aneurysmal subarachnoid hemorrhage (SAH) following carotid artery stenting (CAS) is exceedingly rare and less described, with its underlying mechanism elusive. Here, we present the case of a 75-year-old female who underwent CAS for progressive asymptomatic severe stenosis of the internal carotid artery. Her post-procedural course remained uneventful, with no intracranial hemorrhage detected on the following day\'s magnetic resonance imaging (MRI). However, a routine MRI on the seventh post-procedural day identified a small amount of SAH in the central sulcus on the operative side. In the absence of symptoms, the patient was discharged home after a computed tomography (CT) scan revealed no signs of hemorrhagic enlargement the following day. In this report, we document the rare occurrence of localized SAH post-CAS. There are limited reports of minor SAH following CAS, with the underlying mechanisms remaining unclear. In this report, the localization of SAH aligns with the most critical ischemic sites, indicating that the mechanism of focal SAH after CAS is associated with blood-brain barrier (BBB) disruption due to a rapid increase in blood flow to small vessels with impaired vascular autoregulation. Focal convexity SAH is an easily overlooked finding, and the medical team performing carotid artery revascularization procedures should be aware of the potential for such SAH postoperatively and exercise caution during postoperative imaging interpretation.

Stroke continues to be a major public health issue resulting in high mortality and severe long-term disability. Carotid endarterectomy (CEA) plays an important role in the prevention of ischemic stroke. Complications associated with CEA can be life threatening and prompt recognition is crucial. In this report, we present a patient who presented to the hospital with progressive headache, 2 weeks following CEA. He was neurologically intact and hypertensive. Non-contrast head computed tomography (CT) scan showed convexity subarachnoid hemorrhage (SAH). He was found to have a left internal carotid artery dissection. Patients who present to the hospital following CEA with headache and hypertension benefit from a non-contrast head CT scan. The presence of SAH can be a warning sign of cerebral hyperperfusion syndrome. Carotid artery dissection is also a disease entity that can occur in the post-operative period. Prompt recognition and treatment is crucial for the management of these disease entities.

A 63-year-old man developed reduced consciousness and dysphagia progressively. Examination and parameters were normal, except for a Glasgow Coma Scale score of seven, and his grading on the swallow water test increased from grade 1 to grade 5. Brain imaging and blood tests were unexplainable except by high plasma ammonia. His past medical history included cerebral infarction, hypertension and epilepsy induced by cerebral hyperperfusion syndrome. He was rceiving antiepileptic treatment of continuously intravenously pumped sodium valproate of 64 mg/h for 4 days, which overlapped for 12 hours with taking 500 mg sustained release tablets. Sodium valproate was stopped; testing demonstrated normal plasma concentrations of sodium valproate and elevated concentrations of ammonia. Ornithine aspartate was administrated. The patient\'s level of responsiveness and ammonia levels gradually improved. The patient was also being treated with ceftriaxone sodium for a hypostatic pneumonia and with desmopressin for diabetes insipidus. There is an association between sodium valproate and hyperammonaemia and encephalopathy. Immediate recognition of the serious but uncommon adverse effects is essential. To our knowledge this is the first report of ornithine aspartate being used in this disorder.

OBJECTIVE: Cerebral hyperperfusion syndrome (CHS) is a critical complication in patients who 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.
METHODS: 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.
RESULTS: Twenty-two patients had clinically manifested CHS. Four parameters were detected as risk factors associated with CHS, including effective collateral circulation (P = 0.046), asymmetry ratio of peak systolic velocity of the middle cerebral artery (P = 0.001), severe stenosis or occlusion of the contralateral carotid artery (P = 0.010), and low-density lipoprotein cholesterol (P = 0.025). The area under the curve for the prediction model of CHS in the cohort was 0.835 (95% confidence interval 0.760-0.909).
CONCLUSIONS: In this study, CHS following CAS was associated with effective collateral circulation, ARP, contralateral ICA severe stenosis or occlusion, as well as low-density lipoprotein cholesterol. 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.

Moyamoya disease is a progressive cerebrovascular disorder for which there is no cure. It is characterized by narrowing of and occlusions in the blood vessels that supply the brain, which causes a fine vascular network to develop to serve as collateral pathways. Moyamoya disease can lead to a reduction of blood flow to the brain and increase the risk of stroke. Patients with moyamoya disease may present with ischemic or hemorrhagic complications. Treatment options may involve medical management or surgical revascularization (indirect, direct, or a combined approach). The encephaloduroarteriosynangiosis procedure is a form of indirect revascularization in which a portion of the superficial temporal artery is moved from the scalp to the brain surface. Regardless of the approach, the goal of revascularization is to improve blood flow to the affected area to prevent additional infarcts; the encephaloduroarteriosynangiosis procedure is a viable option to help prevent additional neurologic decline.

Cerebral hyperperfusion syndrome is a rare but serious complication after revascularization procedures for cerebrovascular diseases. Cerebral hyperperfusion syndrome can develop after treatment of acute ischemic stroke, including intravenous thrombolysis and endovascular treatment of large vessel occlusion. However, to the best of our knowledge, there are no previous reports describing cerebral hyperperfusion syndrome after endovascular treatment of medium vessel occlusion (eg, anterior cerebral artery A2/3 segment). We report a case of cerebral hyperperfusion syndrome after endovascular reperfusion therapy for medium vessel occlusion. A 70-year-old woman with a history of hypertension and dyslipidemia was transferred by ambulance to our hospital because of immobility and slurred speech. She had mild right lower extremity paralysis, and her symptoms appeared improved compared with onset. She was diagnosed with cerebral infarction in the left frontal lobe. After hospitalization, her neurological symptoms worsened and she was referred to our department. We performed endovascular reperfusion therapy for left anterior cerebral artery A2 occlusion. Recanalization was achieved with residual stenosis. Despite the lack of complications associated with the procedure, the patient had prolonged disorientation, severe hemiplegia, and aphasia. Arterial spin labeling demonstrated hyperperfusion in the left anterior cerebral artery area. The symptoms gradually improved under strict blood pressure control. This report provides evidence that cerebral hyperperfusion syndrome can occur even after endovascular treatment for medium vessel occlusion. Arterial spin labeling was useful in detecting hyperperfusion.

BACKGROUND: 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.
OBJECTIVE: 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.
OBJECTIVE: To assess the frequency and characteristics of CHS in patients with MMD after revascularization operations.
METHODS: 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.
RESULTS: 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 (2.8%) hemispheres, seizures in 4 (2.8%) hemispheres. The results of multivariate logistic regression analysis indicated that preoperative hypertension (OR 4.705, 95% CI 1.323 ~ 12.554, p = 0.014), cerebral hemorrhage onset (OR 5.390, 95% CI 1.408 ~ 20.642, p = 0.014) and higher Hct level (OR 1.171, 95% CI 1.051 ~ 1.305, p = 0.004) were significantly associated with CHS after combined revascularization.
CONCLUSIONS: Preoperative hypertension, cerebral hemorrhage onset, and higher Hct level were independent risk factors for CHS after combined revascularization.

Cerebral hyperperfusion syndrome (CHS) is a rare prodrome of symptoms, including headaches, focal neurological deficits, seizures, or encephalopathy. Herein, we report a unique case of focal motor status epilepticus (Epilepsia partialis continua [EPC]). A 76-year-old male underwent right carotid stenting (CAS) for symptomatic high-grade stenosis. Immediately post-operation, he was recovering well without neurologic deficits; however, four days later, his blood pressure increased, and he experienced focal motor seizures involving the left arm and face without impaired awareness. He was managed with antihypertensive and antiseizure medications. Subsequently, his respiratory function worsened, necessitating intubation for status epilepticus. Repeated imaging demonstrated only the previously known infarcts without cerebral edema, bilaterally patent carotid arteries or any signs of acute infarct or intracerebral hemorrhage.  While CHS is a rare syndrome with well-documented symptomatology, focal motor status epilepticus can occur abruptly without the more typical CHS symptoms, despite the best preventive measures.