摘要:Cerebral venous sinus thrombosis (CVST) is a rare condition whose most common and sometimes only symptom is headache. Alas, diagnosis and treatment of CVST is often delayed or overlooked because of its high clinical variability. Using guidelines advices in detecting warning signs or symptoms of secondary headaches might ease the diagnosis of CVST. The article presents the case of a woman who is in treatment for chronic migraine and assessed for secondary headache in a multidisciplinary outpatient headache program. Alert symptoms like sudden worsening headache presentation, along with anamnestic cues, prompted neuroimaging that detected left transverse sinus thrombosis whose onset was difficult to date.