Percutaneous transluminal angioplasty for persistent primitive hypoglossal artery stenosis: illustrative case

BACKGROUND: We report a case of symptomatic, progressive stenosis of a persistent primitive hypoglossal artery (PPHA), which was successfully treated with percutaneous transluminal angioplasty (PTA) of the origin of the PPHA. The PPHA is a type of carotid-basilar anastomosis with an incidence of 0.02% to 0.10%. It originates from the internal carotid artery (ICA), passes through the hypoglossal canal, and merges with the basilar artery. In many cases, the ipsilateral vertebral artery is hypoplastic; therefore, PPHA stenosis causes cerebral infarction in the posterior circulation territory, as in this case. OBSERVATIONS: The patient’s right PPHA had severe and progressive stenosis; therefore, he experienced cerebral infarction despite medical treatment. Therefore, PTA for the stenosis was performed, which ceased the recurrence of cerebral infarction and dizziness by improving blood flow in the posterior circulation. LESSONS: Several reports have described ICA stenosis accompanied by PPHA or PPHA stenosis in patients receiving endovascular treatments. Almost all cases were nonprogressive, and the treatment procedure was stenting. However, in our case, the PPHA stenosis was progressive, and we performed PTA because the patient experienced resistance to antiplatelet drugs and had poor collateral flow.