Abstract
BACKGROUND: Eagle syndrome, an uncommon condition, causes symptoms due to neural and/or vascular compression from an elongated styloid process or calcified stylohyoid ligament and can also complicate other planned surgical procedures. OBSERVATIONS: A 42-year-old female with loss of balance, dizziness, and ataxic gait underwent cranial magnetic resonance imaging (MRI), revealing a right-sided Koos grade IV vestibular schwannoma. Initially, a retrosigmoid craniotomy for tumor resection was planned. However, preoperative MRI and computed tomography (CT) showed a dilated right-sided mastoid emissary vein, tortuous scalp and paraspinal veins, and bilateral elongated styloid processes. CT angiography and digital subtraction angiography indicated Eagle syndrome-related compression of both internal jugular veins and concurrent occlusion of the left internal jugular vein at the jugular foramen. Consequently, given the risk of damaging venous structures, Gamma Knife radiosurgery was chosen over resection. LESSONS: This case highlights the importance of adapting treatment plans based on patient-specific anatomical and pathological factors. In situations in which traditional surgery poses risks to sensitive structures such as the venous system, alternative approaches like radiosurgery offer safer yet effective options. Comprehensive risk-benefit evaluations are crucial for such decisions.