TY - JOUR AU - Encarnacion-Santos, Daniel A. AU - Dubovoy, Andrey Vladimirovish AU - Chmutin, Gennady AU - Chmutin, Egor AU - Batista-Geraldino, Emmanuel AU - Ibrohimovich, Shahboz Boboev AU - Mainer, Adam Romanovish PY - 2026 DA - 2026/08/21 TI - Moyamoya Disease in an 18-Month-Old Child with Down Syndrome: A Case Report, Surgical Management, and Literature Review JO - OBM Neurobiology SP - 347 VL - 10 IS - 03 AB - Moyamoya disease (MMD) is a chronic, progressive cerebrovascular disorder characterized by stenosis of the terminal portion of the bilateral internal carotid arteries and the formation of an abnormal collateral vascular network at the skull base. This condition was first described by Suzuki and Takaku in 1969. This case report aims to describe the surgical management and the pathological and physiological characteristics of moyamoya disease in a child, focusing on a rare case involving an infant with Down syndrome also affected by MMD. We report an 18-month-old child who presented to the emergency department with jerky movements, brief episodes of staring or blanking, muscle weakness (lasting up to 5 minutes), rigidity, drooling, and behavioral changes. These symptoms, identified as seizures, recurred 30 minutes later. The infant also exhibited signs of right hemiparesis and a Glasgow Coma Scale (GCS) score of 9-12. Magnetic Resonance Imaging (MRI) suggested the diagnosis, which was subsequently confirmed by cerebral angiography as Moyamoya disease (MMD). The patient underwent direct extracranial-intracranial (EC-IC) revascularization. This involved a frontoparietotemporal osteoplastic craniotomy, followed by microsurgical anastomosis between the parietal branch of the left superficial temporal artery (STA) and the M4 segment of the left middle cerebral artery (MCA), supplemented with encephaloduromyoperiosynangiosis. Postoperatively, the patient developed hydrocephalus secondary to ventricular dilation. Consequently, a surgical reintervention was planned. Surgical Reintervention: During the reintervention, 350 mL of cerebrospinal fluid (CSF) was manually extracted with a syringe to reduce intracranial pressure, and an external ventricular drain (EVD) was placed intraoperatively to facilitate ongoing CSF drainage. Following the surgical reintervention, the patient was admitted to the ICU. Management included conservative treatment and antibiotics, with particular attention to patient comfort through hydration and the control of fever and hydrocephalus. SN - 2573-4407 UR - https://doi.org/10.21926/obm.neurobiol.2603347 DO - 10.21926/obm.neurobiol.2603347 ID - Encarnacion-Santos2026 ER -