Evaluation of Revascularization in Different Suzuki Stages of Ischemic Moyamoya Disease by Whole-Brain CT Perfusion

Mass cytometry revealed the circulating immune cell landscape across different Suzuki stages of Moyamoya disease

Moyamoya disease (MMD) is a cerebrovascular disorder marked by progressive arterial narrowing, categorized into six stages known as Suzuki stages based on angiographic features. Growing evidence indicates a pivotal role of systemic immune and inflammatory responses in the initiation and advancement of MMD. This study employs high-dimensional mass cytometry to reveal the immunophenotypic characteristics of peripheral blood immune cells (PBMCs) at various Suzuki stages, offering insights into the progression of MMD. PBMC samples from eight patients with early-stage MMD (Suzuki stages II and III) and eight patients with later-stage MMD (Suzuki stages IV, V, and VI) were analyzed using high-dimensional mass cytometry to evaluate the frequency and phenotype of immune cell subtypes. We identified 15 cell clusters and found that the immunological features of early-stage MMD and later-stage MMD are composed of cluster variations. In this study, we confirmed that, compared to later-stage MMD, the early-stage MMD group exhibits an increase in non-classical monocytes. As the Suzuki stage level increases, the proportions of plasmacytoid DCs and monocyte-derived DCs decrease. Furthermore, T cells, monocytes, DCs, and PMN-MDSCs in the early-stage MMD group show activation of the canonical NF-κB signaling pathway. We summarized and compared the similarities and differences between early-stage MMD patients and later-stage MMD patients. There is a potential role of circulating immune dysfunction and inflammatory responses in the onset and development of MMD.

Prediction of the mean transit time using machine learning models based on radiomics features from digital subtraction angiography in moyamoya disease or moyamoya syndrome-a development and validation model study

Background

Digital subtraction angiography (DSA) is an important technique for diagnosis of moyamoya disease (MMD) or moyamoya syndrome (MMS), and computed tomography perfusion (CTP) is essential for assessing intracranial blood supply. The aim of this study was to assess whether radiomics features based on images of DSA could predict the mean transit time (MTT; outcome of CTP) using machine learning models.

Methods

The DSA images and MTT values of adult patients with MMD or MMS, according to the diagnostic guidelines for MMD, as well as control cases, were retrospectively collected in the Guangdong Provincial People's Hospital between January 2018 and December 2020. A total of 93 features were extracted from the images of each case through 3-dimensional (3D) slicer. After features preprocessing and filtering, 3-4 features were selected by the least absolute shrinkage and selection operator (LASSO) regression algorithm. Prediction models were established using random forest (RF) and support vector machine (SVM) for MTT values. Single-factor receiver operating characteristic (ROC) curve analysis and partial-dependence (PD) profiles were conducted to investigate selected features and prediction models.

Results

Our results showed that prediction models based on RF models had the best performance in frontal lobe {area under the curve (AUC) [95% confidence interval (CI)] =1.000 (1.000-1.000)], parietal lobe [AUC (95% CI) =1.000 (1.000-1.000)], and basal ganglia/thalamus [AUC (95% CI) =0.922 (0.797-1.000)] in the test set, whereas the SVM model performed the best in the temporal lobe [AUC (95% CI) =0.962 (0.876-1.000)] in the test set. The AUC values in the test set were greater than 0.9. The PD profiles showed good robustness and consistency.

Conclusions

Prediction models based on radiomics features extracted from DSA images demonstrate excellent performance in predicting MTT in patients with MMD or MMS, which may provide guidance for future clinical practice.

Clinical features, surgical treatment, and long-term outcomes of moyamoya disease in a single institution of Fujian, Southeast China: A retrospective study

At present, detailed demographic and clinical data of moyamoya disease (MMD) in the population of Southeast China are lacking. Therefore, this study aimed to evaluate the epidemiological and clinical features of MMD in Southeast China. Our cohort included 170 patients diagnosed with MMD over the preceding 5 years. Clinical characteristics were obtained through a retrospective chart review, while follow-up information and outcomes were obtained through clinical visits and imaging. The median age at symptom onset was 49 years (range 4-73), with a peak in the age distribution observed at 41 to 60 years. The female-to-male ratio was 1.125 (90/80), and the ratio of the ischemic type to the hemorrhagic type was 2.33 (119/50). The most common initial symptom was an ischemic event. The 5-year Kaplan-Meier risk of stroke was 4.9% for all patients treated with surgical revascularization. Of all patients, 83.9% were able to live independently with no significant disability, and 89.8% showed improved cerebral hemodynamics. Our study provided detailed demographic and clinical data on Southeastern Chinese patients with MMD, which was consistent with findings in other parts of China. Raising clinical awareness of MMD in primary hospitals is important to facilitate early diagnosis and timely treatment of MMD patients.

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

Background

Cerebral 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.

Methods

A 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.

Results

A 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%).

Conclusion

The 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.

Effect of newly developed scissors-attached micro-forceps on the recipient clamp time and occurrence of anastomotic site infarction after bypass surgery for moyamoya disease

Introduction

This study aimed to examine the effect of newly developed scissors-attached micro-forceps in superficial temporal artery-to-middle cerebral artery (STA-MCA) anastomosis for moyamoya disease (MMD).

Materials and methods

Of 179 consecutive STA-MCA anastomoses on 95 hemispheres of 71 MMD patients at the University of Fukui Hospital between 2009 and 2023, 49 anastomoses on 26 hemispheres of 21 patients were enrolled in this retrospective cohort clinical trial intraoperative indocyanine green video-angiography did not demonstrate bypass patency in three anastomoses in two patients who were excluded. Twenty-one anastomosis in 19 hemispheres of 16 patients were performed using the conventional micro-forceps (conventional group, CG), and 25 anastomoses in 22 hemispheres of 19 patients were performed using scissors-attached micro-forceps (scissors group, SG). A small infarction near the anastomotic site detected using postoperative diffusion-weighted imaging was defined as anastomotic site infarction (ASI). Factors affecting the occurrence of ASI were examined by univariate, logistic regression, and receiver operating curve (ROC) analysis.

Results

There were no significant differences in clinical parameters such as age, sex, number of sacrificed branches, number of sacrificed large branches, and number of sutures between the CG and SG. However, the clamp time and occurrence of ASI were significantly lower in the SG than in the CG. Logistic regression analysis revealed that the clamp time was the only significant factor predicting the occurrence of ASI. A receiver operating curve analysis also revealed that the clamp time significantly predicted the occurrence of ASI (area under the curve, 0.875; cutoff value, 33.2 min).

Conclusion

The newly developed scissors-attached micro-forceps could significantly reduce the clamp time and occurrence of ASI in STA-MCA anastomosis for MMD.

Predictive value of CT perfusion-derived parameters in Moyamoya disease

OBJECTIVE

To explore the applicability of CT perfusion-derived parameters and collateral index in prediction of functional and clinical outcomes in patients with Moyamoya disease (MMD) who have not been treated surgically.

METHODS

All hemispheres were categorized into four groups: those with ischemic (IS) lesions, hemorrhagic (HE) lesions, subarachnoid hemorrhage (SAH) and normal hemisphere (NH). The clinical review included primary outcomes (whether a patient survived the cerebrovascular event) and secondary outcomes (the modified Rankin scale [mRS] and Katz-activity of daily living [ADL] scale). CTP-derived parameters of the frontal, temporal lobe and basal ganglia were calculated. Collateral index of the hypointensity ratio (HIR) was defined as a volume of Tmax >10 s/ Tmax >4 s.

RESULTS

Between December 2020 and December 2021, 21 MMD patients (15 bilateral cases and 6 unilateral cases, for a total of 36 hemispheres) were retrospectively included. Compared with the NH group, the IS group showed obviously abnormal hemodynamics. As for the primary outcomes, HIR showed an excellent area under the curve of 0.955 (95 % CI: 0.886-1.000, p < 0.001). Significant correlations were found between CTP-derived parameters and secondary outcomes. Furthermore, HIR was significantly correlated with mRS (r = 0.576, p = 0.001) and ADL scores (r = 0.644, p < 0.001).

CONCLUSION

Among different imaging types, IS hemispheres were characterized by distinct changes of hemodynamic parameters. Collateral index of HIR could be considered a clinically accessible and promising indictor of functional and clinical outcomes in MMD.

White and Gray Matter Perfusion in Children with Moyamoya Angiopathy after Revascularization Surgery

INTRODUCTION

Surgical revascularization is very effective in patients with moyamoya angiopathy (MMA) and leads to improvements in cortical perfusion parameters. However, changes in white matter hemodynamics are still underestimated. To date, only a few studies have examined brain perfusion changes within deep white matter after bypass surgery in patients with MMA.

METHODS

Ten children with MMA were evaluated using the CT perfusion technique before and after revascularization surgery. Brain perfusion parameters within gray and white matter were compared before and after surgery. The correlations between the perfusion parameters before surgery and the Suzuki stage, as well as between the perfusion parameters and the cognitive scores, were also evaluated.

RESULTS

Brain perfusion parameters improved significantly in both gray matter (predominantly due to cerebral blood flow within the anterior circulation, p < 0.01) and white matter (predominantly due to cerebral blood volume within the semiovale centrum, p < 0.001). We revealed that the pattern of improvement in perfusion in white matter differed from the pattern of improvement in perfusion in gray matter. Significant correlations were revealed between the Suzuki stage before surgery and the perfusion parameters within the posterior cerebral artery circulation (adjusted p < 0.05). There were also significant correlations between cognitive scores and brain perfusion parameters in gray matter and white matter (adjusted p < 0.05).

CONCLUSIONS

The perfusion parameters of gray matter and white matter in the brain improve differently after bypass surgery in patients with MMA. Different hemodynamics within these compartments could explain this.

T1w/T2w ratio is associated with the brush sign and perfusion delay in watershed regions in patients with moyamoya angiopathy

BACKGROUND

It has been shown recently using the T1w/T2w mapping technique that white matter microstructural integrity impairments exist in watershed regions patients with moyamoya angiopathy (MMA). We hypothesized that these changes could be associated with the prominence of other neuroimaging markers of chronic brain ischemia, such as perfusion delay and the brush sign.

METHODS

Thirteen adult patients with MMA (24 affected hemispheres) were evaluated using brain MRI and CT perfusion. The T1w/T2w signal intensity ratio, which reflects white matter integrity, was calculated in watershed regions (centrum semiovale and middle frontal gyrus). Brush sign prominence was evaluated with susceptibility-weighted MRI. Additionally, brain perfusion parameters such as cerebral blood flow (CBF), cerebral blood volume (CBF), and mean transit time (MTT) were assessed. Correlations between white matter integrity and perfusion changes in watershed regions, as well as the prominence of the brush sign, were evaluated.

RESULTS

Statistically significant negative correlations between the prominence of the brush sign and the T1w/T2w ratio values from the centrum semiovale and middle frontal white matter were found (R = -0.62 to 0.71, adjusted p < 0.05). Furthermore, there was a positive correlation between the T1w/T2w ratio values and the MTT values from the centrum semiovale (R = 0.65, adjusted p < 0.05).

CONCLUSIONS

We revealed that T1w/T2w ratio changes are associated with the prominence of the brush sign as well as white matter hypoperfusion in watershed regions in patients with MMA. This could be explained by chronic ischemia due to venous congestion in the deep medullary vein territory.

Segmented carotid endarterectomy for treatment of Riles type 1A common carotid artery occlusion

OBJECTIVE

Common carotid artery occlusion (CCAO) is a rare cause of cerebrovascular events. Symptomatic lesions are resistant to medical treatment and revascularization is often required, but there is no consensus on the treatment of CCAO at present. Riles type 1A CCAO is most likely to benefit from revascularization because it has patent outflow tract (internal carotid artery) which was supplied by patent external carotid artery (ECA) from collateral circulation. We described a novel surgical technique improved on the basis of the carotid endarterectomy (CEA) for treatment of Riles type 1A CCAO.

METHODS

We rigorously screened ten patients with symptomatic Riles type1A CCAO for surgery from January 2017 to May 2019 and performed a full preoperative assessment of the inadequate collateral circulation compensation. Moreover, we retrospectively reviewed our experience of the segmented CEA in the treatment of them in our single center.

RESULTS

Segmented CEA was performed on the left side in four cases and on the right side in six cases. The technical success rate of the procedure was 100%. Primary suture was used in nine cases. Only one patient (right CCAO) who had a history of neck radiotherapy was treated by the patch CEA. The mean temporary blocking time during surgery was 52.8 ± 9.15 min. The mean temporary blocking time for treating the upper segment of the common carotid artery (CCA) was 11.1 ± 2.64 min. In the postoperative period, cerebral perfusion on the ipsilateral site improved in all patients, myocardial infarction occurred in one patient, and recurrent laryngeal nerve damage occurred in another. No ischemic events or re-occlusion or restenosis (> 50%) of the treated CCA occurred during the mean follow-up of 32.6 ± 9.3 months. The preoperative mean modified Rankin Scale (mRS) score was 1.9 (range, 1-3; median, 2). At last follow-up for all patients, the mRS score was 1 (range, 0-3; median, 1).

CONCLUSION

Segmented CEA, which utilizes the compensatory effect of collateral circulation, is an effective and safe technique to treat patients suffering from Riles type 1A CCAO with hemodynamic cerebrovascular compromise.

Moyamoya syndrome with ruptured aneurysm in α‑thalassemia: A case report

Moyamoya syndrome (MMS) refers to the moyamoya vascular disease associated with various systemic diseases and conditions, including sickle cell anemia, Fanconi anemia and iron deficiency anemia. However, the association between MMS and other hemoglobinopathies is less frequently observed. MMS, like moyamoya disease, is a cerebrovascular condition that is characterized by chronic progressive stenosis or occlusion at the ends of the bilateral internal carotid arteries, anterior cerebral arteries and the beginning of the middle cerebral arteries, and is secondary to the formation of an abnormal vascular network at the base of the skull. Patients with MMS are prone to thrombosis, aneurysm and bleeding. The present study reports the case of a 43-year-old man with α-thalassemia who presented with moyamoya vessels with a ruptured aneurysm bleeding into the ventricle. α-thalassemia is considered as an extremely rare but potential cause of MMS. Since MMS is a progressive disease, early diagnosis and treatment is vital to prevent the disease from worsening.

A single - center retrospective observational study on patients undergoing Encephalo-Duro-Arterio -Myo-Synangiosis in patients with moyamoya disease

BACKGROUND:

Many cases of moyamoya disease are refractory to conventional medical therapy, hence surgical revascularization techniques have emerged as one of the primary choices of treatment. In this study, we present the functional and angiographic outcomes of patients undergoing encephalo-duro-arterio-myo-synangiosis (EDAMS).

METHODS:

This is a retrospective observational cohort study, done over 8 years (2012–2020) in a neurological center in Eastern India. Data were retrieved from the hospital's electronic system, recorded in a standard data abstract sheet, and analyzed.

RESULTS:

This study included 75 patients, with a male (n = 42; 56.0%) preponderance. Majority belonged to the pediatric age group (≤18 years) (n = 70; 93.3%); remaining adult population included 5 (6.6%) patients. The most common presenting complaint was that of an ischemic cerebrovascular accident (CVA) (n = 57; 76.0%). Symptomatic hemispheres (n = 69; 92.0%) were treated and later followed if they had progressed to bilateral disease formation. Preoperative DSA showed 50 (71.4%) to have Suzuki grade 3 type of angiographic findings. Postoperative complications included worsening unilateral hemiparesis 4 (40%), slurring of speech (n = 2; 20.0%), hematoma (n = 2; 20.0%), and surgical site infection (n = 2; 20.0%). One patient succumbed to his illness on the second postoperative day. A postoperative angiogram showed regression of moyamoya vessels in the majority (n = 69; 93.3%) of patients. All (n = 74; 100%) had an intensification of transdural vessels; none had a regression. None of the study participants showed an intensification of moyamoya vessels. Many of our patients (83.8%) had a good grade of revascularization (modified Matsushima and Inaba A and B), while 16.2% had low-grade revascularization (grade C). On assessing outcomes using a modified Rankin Score, a large number of our patients had an excellent (n = 45, 60%) neurological outcomes.

CONCLUSION:

There was a bimodal age distribution with most of them presenting with ischemic CVA. This procedure (EDAMS) had good angiographic (Matsushima and Inaba) and functional (modified Rankin Score) outcomes.