Case Of the Week (COW) 24 March 2013
Answer:
Left Persistent Primitive Hypoglossal Artery.
Findings:
An artery is seen arising from the left cervical internal carotid artery and forming the basilar artery. The vertebral artery is not seen on the left sid and hypoplastic on the right side. Focal dilation of the cervical internal carotid artery just proximal to this was also noticed. In CT scan the left hypoglossal canal was found to be larger than that on the right side.
Discussion:
The persistent primitive hypoglossal artery (PPHA) is a rare remnant of one of the four embryonal carotid-basilar anastomoses. The reported incidence is 0.02~0.26% of angiograms or autopsy cases The criteria for diagnosis of PPHA are that the artery arises from the cervical ICA at the levels of C-1 to C-3, the artery passes through the hypoglossal canal to the posterior cranial fossa, the basilar artery is filled only by the distal part of the junction with the anastomosis, and angiography indicates deficiency or absence of the posterior communicating Artery. When a PPHA is present, usually the vertebral artery is either absent on the ipsilateral side and hypoplastic on the opposite side, or hypoplastic on both sides. The main coexisting lesions are cerebral aneurysm and occlusive cerebrovascular disease.
Ref: Persistent Primitive Hypoglossal Artery Associated with Cerebral Aneurysm Korean journal of cerebrovascular surgery -June 2006. Vol 8 No 2 , Page 132-134
Contributed By:
Dr. Babu Peter MD, DNB
Associate Professor, Barnard Institute of Radiology, Chennai
Senior Consultant Radiologist, Aarthi Scans, Chennai
Answer:
Left Persistent Primitive Hypoglossal Artery.
Findings:
An artery is seen arising from the left cervical internal carotid artery and forming the basilar artery. The vertebral artery is not seen on the left sid and hypoplastic on the right side. Focal dilation of the cervical internal carotid artery just proximal to this was also noticed. In CT scan the left hypoglossal canal was found to be larger than that on the right side.
Discussion:
The persistent primitive hypoglossal artery (PPHA) is a rare remnant of one of the four embryonal carotid-basilar anastomoses. The reported incidence is 0.02~0.26% of angiograms or autopsy cases The criteria for diagnosis of PPHA are that the artery arises from the cervical ICA at the levels of C-1 to C-3, the artery passes through the hypoglossal canal to the posterior cranial fossa, the basilar artery is filled only by the distal part of the junction with the anastomosis, and angiography indicates deficiency or absence of the posterior communicating Artery. When a PPHA is present, usually the vertebral artery is either absent on the ipsilateral side and hypoplastic on the opposite side, or hypoplastic on both sides. The main coexisting lesions are cerebral aneurysm and occlusive cerebrovascular disease.
Ref: Persistent Primitive Hypoglossal Artery Associated with Cerebral Aneurysm Korean journal of cerebrovascular surgery -June 2006. Vol 8 No 2 , Page 132-134
Contributed By:
Dr. Babu Peter MD, DNB
Associate Professor, Barnard Institute of Radiology, Chennai
Senior Consultant Radiologist, Aarthi Scans, Chennai