Severe Arterial Stenosis Increases Infarction Risk in Adult Moyamoya Revascularization

Severe focal stenosis in major intracranial arteries is significantly associated with postoperative major arterial cerebral infarction in adult patients undergoing combined revascularization for ischemic moyamoya disease, according to a retrospective clinical analysis conducted at Peking University International Hospital. Evaluating 119 adult patients treated between June 1, 2021, and October 31, 2024, researchers identified that focal narrowing of 50 percent or greater in primary cerebral vessels markedly elevated complication rates, whereas mild stenosis, complete arterial occlusion, and advancing Suzuki stages did not demonstrate statistically significant correlations with postoperative infarction.

Moyamoya disease is an uncommon cerebrovascular condition marked by progressive spontaneous narrowing or occlusion of the distal internal carotid artery and the proximal segments of its major branches, typically accompanied by the proliferation of fragile, net-like collateral vessels at the base of the brain. While surgical revascularization remains the primary established treatment for restoring cerebral perfusion, postoperative ischemic complications occur in approximately 5 percent of operations, with prior literature documenting rates reaching 7.6 percent among adult cohorts. Earlier investigations suggested potential associations with elevated Suzuki stages, preoperative ischemic symptoms, acute-stage surgical timing, elevated carbon dioxide partial pressures, hypovolemia, reduced hematocrit levels, and blood pressure lability, yet complication rates at the study center persisted despite active management of these parameters.

The retrospective single-center investigation examined an overall institutional cohort of 307 patients diagnosed with moyamoya disease according to the 2012 diagnostic guidelines of the Research Committee on Spontaneous Occlusion of the Circle of Willis. The surgical population included 42 pediatric patients and 145 adult patients, the latter comprising 26 cases of hemorrhagic moyamoya disease and 119 cases of ischemic moyamoya disease, defined as patients presenting without a prior history of intracranial hemorrhage. All 119 adult ischemic patients received combined revascularization surgery under protocols reviewed and approved by the Ethics Committee of Peking University International Hospital, with clinical data utilized following patient informed consent.

Standardized perioperative protocols were enforced across all included ischemic cases, incorporating weight-adjusted intravenous fluid hydration initiated three days prior to surgery alongside subcutaneous low-molecular-weight heparin administered for three days and withheld twelve hours preoperatively to mitigate thrombotic complications. Patients suffering an acute infarction within one month or presenting with more than three transient ischemic attacks in a single month were considered surgical contraindications, requiring medical stabilization for at least one month before revascularization was offered. Systemic blood pressure was assessed four times daily at set intervals to determine basal reference values, mandating normal and stable glucose and blood pressure profiles for at least three consecutive days before operative intervention. Preoperative diagnostic workups consistently incorporated digital subtraction angiography, head magnetic resonance imaging, and computerized tomography perfusion imaging.

Operative protocols were tailored specifically to the hemodynamic demands of ischemic pathology, with anesthesiologists administering hypervolemic fluid therapy and elevating intraoperative systolic blood pressure 10 to 20 mmHg above basal baseline measurements without lowering pressure following bypass completion. Revascularization indications followed established Japanese Ministry of Health and Welfare guidelines, prioritizing the symptomatic and hemodynamically compromised cerebral hemisphere.

Postoperative neuroimaging protocols mandated cranial computed tomography at four to six hours following surgery, supplementary magnetic resonance imaging with diffusion-weighted imaging sequences at five to seven days, and immediate repeat imaging upon any acute neurological deterioration. Suzuki stages were evaluated across both hemispheres, and major arterial lesions across the internal carotid artery, anterior cerebral artery, middle cerebral artery, and posterior cerebral artery were measured using handheld digital calipers according to WASID criteria. Vascular caliber evaluations focused on prebifurcation segments and classified lesions into normal, mild stenosis below 50 percent, severe stenosis of 50 percent or greater, and complete occlusion, an approach adopted due to the uniformly slender anatomy of moyamoya vasculature and the technical challenge of separating 50 to 69 percent from 70 to 99 percent narrowing. Two independent neurosurgeons with over a decade of subspecialty experience conducted blinded image analyses, resolving discrepancies through consultation with a third cerebrovascular specialist.

Postoperative infarctions occurred in 11 cerebral hemispheres across 8 patients, representing an overall ischemic complication rate of 5.52 percent among the 145 surgically managed adults, with 3 patients exhibiting bilateral infarcts and zero ischemic events noted in pediatric or hemorrhagic subgroups. The authors categorized infarctions into three distinct morphological presentations: operative area infarctions strictly limited to the craniotomy site, scattered infarctions consisting of small discontinuous lesions smaller than a vascular territory, and major artery infarctions involving complete distribution zones of the anterior, middle, posterior, or internal carotid arteries. Because operative area and scattered infarctions produced circumscribed parenchymal damage and better functional outcomes, analytical modeling focused specifically on the determinants of major arterial infarction.

Logistic regression analysis conducted with IBM SPSS Statistics demonstrated that preoperative Suzuki staging was not significantly associated with postoperative major arterial infarction, yielding an odds ratio of 0.815 with a 95 percent confidence interval of 0.565 to 1.178 (p = 0.277). When stenosis severity was categorized as an ordinal variable, no statistically significant associations emerged; however, when treated as a disordered categorical variable relative to normal baseline vessels, severe stenosis was significantly correlated with postoperative infarction. The regression model calculated an odds ratio of 49.500 for severe anterior cerebral artery stenosis (95% CI, 5.083–482.011; p = 0.001), 24.000 for middle cerebral artery stenosis (95% CI, 1.459–394.881; p = 0.026), 54.333 for posterior cerebral artery stenosis (95% CI, 4.307–685.462; p = 0.002), and 8.833 for internal carotid artery stenosis (95% CI, 0.730–106.821; p = 0.046).

Emergency digital subtraction angiography performed on symptomatic patients confirmed that new cerebral infarctions aligned directly with vessels demonstrating severe preoperative narrowing. In an illustrative report of a 40-year-old female presenting with left lower extremity weakness who developed coma, aphasia, and hemiplegia following right-sided combined surgery, emergent angiography revealed aggravated stenosis at the left internal carotid terminus matching an acute infarction on diffusion-weighted imaging. In a second documented case, a 47-year-old male with bilateral upper extremity numbness and weakness remained comatose two hours after left-sided combined revascularization; immediate angiography confirmed acute occlusion of a preoperatively stenosed right internal carotid artery, while subsequent computed tomography demonstrated bilateral hypoattenuation across the anterior cerebral artery territory.

The study authors suggested that severe non-occluded stenosis creates an unstable focal hemodynamic environment where distal parenchymal perfusion relies entirely on a narrowed lumen in the absence of mature collateral networks, leaving the vessel vulnerable to acute thrombosis, spasm, or collapse during perioperative intracranial pressure fluctuations. The authors noted key research limitations, including the retrospective single-center design, the inability to control for potential confounding variables such as age and operative hemisphere, and a small total number of infarction events that produced extremely wide statistical confidence intervals indicative of potential model overfitting.

Subject of Research: Risk factors for postoperative cerebral infarction following combined revascularization in adult ischemic moyamoya disease

Article Title: Severe stenosis of major intracranial arteries: an important risk factor for infarction complications after combined revascularization in adult patients with ischemic moyamoya disease

Article References: Tan, C., Ye, X., Niu, H., Duan, R., Shi, G., Zhao, Y., & Wang, R. (2026). Severe stenosis of major intracranial arteries: an important risk factor for infarction complications after combined revascularization in adult patients with ischemic moyamoya disease. Chinese Neurosurgical Journal, 12(1), Article 12. https://doi.org/10.1186/s41016-026-00430-0

Image Credits: AI Generated

DOI: 10.1186/s41016-026-00430-0

Keywords: moyamoya disease, revascularization surgery, cerebral infarction, intracranial arterial stenosis, digital subtraction angiography, ischemic stroke, neurosurgery, Suzuki stage, Severe, stenosis, major, intracranial