Cystic angiomatosis is a rare bone condition with complex presentation and difficult treatment. Current management strategies have poorly tolerated side effects and a low likelihood of disease eradication. The control of calvarial lesions that are symptomatic usually involves surgical excision and subsequent cranioplasty. This paradigm can present with a risk of morbidity and mortality depending on the anatomy of the lesion. Here, the authors present a novel approach to a difficult-to-treat occipital calvarial lesion directly overlying the transverse sinus, performing a small, partial-thickness craniectomy and alcohol sclerotherapy in a combined neurosurgery-neuroendovascular approach. At 3 years after treatment, the authors noted a complete, encouraging radiographic and clinical outcome.