Anterior choroidal artery variant and acute embolic stroke. Case report

Internal carotid artery-persistent primitive anterior choroidal artery aneurysms: report of two cases and literature review

PURPOSE

Persistent primitive anterior choroidal artery (PPAChA) is a rare vascular anomaly. The clinical course of internal carotid artery (ICA)-PPAChA aneurysms has not been well described.

CASE REPORTS

We report two patients with an ICA-PPChA aneurysm and summarize previously reported cases.

RESULTS

Including our two, a total of 10 patients with an ICA-PPAChA aneurysm have been reported. Data were not described for one. Among the remaining nine, five patients (56%) experienced aneurysmal rupture. Five patients underwent surgical clipping and four underwent endovascular coiling. The procedure was completed in all but one patient who had a tiny branch artery adherent to the aneurysm; this patient was converted from clipping to aneurysm coating with a cotton sheet. Among the other eight patients, one who underwent coiling experienced an internal capsule infarction. The remaining seven had a satisfactory postoperative course; however, an asymptomatic occlusion of the PPAChA at its origin was noted on postoperative angiography in one.

CONCLUSION

PPChA is associated with a high incidence of aneurysm formation and rupture. During treatment of ICA-PPAChA aneurysms, obstruction of the PPAChA and any surrounding perforating arteries should be avoided to prevent ischemic stroke.

Coexistence of anterior choroidal artery and posterior cerebral artery retia mirabilia presenting with subarachnoid hemorrhage: illustrative case

BACKGROUND

A rete mirabile is a rare vascular anomaly, with posterior cerebral artery (PCA) involvement being especially rare. Its pathogenesis has been speculated as a remnant of "distal annexation" between the primitive anterior choroidal artery (AchA) and the PCA at this site, but the exact mechanisms remain unclear.

OBSERVATIONS

A 29-year-old man presented with subarachnoid hemorrhage. Arteriovenous malformation in the medial temporal lobe was initially suspected, but an arteriovenous shunt was not detected. First, conservative treatment was administered; however, rebleeding occurred 1 month later. Carotid angiography revealed a network-like cluster of blood vessels at the choroidal point of the AchA, suggesting a rete mirabile; these vessel clusters led to the persistent temporo-occipital branch of the AchA. Furthermore, an aneurysm was detected at the junction between the rete mirabile and the persistent temporo-occipital branch of the AchA. Additionally, vertebral angiography demonstrated a rete mirabile at the P2 segment. These findings suggested the coexistence of AchA and PCA retia mirabilia. Consequently, the aneurysm was clipped using a subtemporal approach to prevent re-rupture, and the postoperative course was uneventful.

LESSONS

This first report of coexisting AchA and PCA retia mirabilia supports the remnant of distal annexation between the primitive AchA and the PCA as the reason for rete formation at this site.

Clipping of Unruptured Anterior Choroidal Artery Aneurysms Together with Small Branches: Safety Confirmation Using Intraoperative Indocyanine Green Video-Angiography and Intraoperative Neurophysiological Monitoring

BACKGROUND

In treating anterior choroidal artery (AChA) aneurysms, preserving the AChA main trunk is of course necessary to prevent postoperative ischemic complications. However, in practice, complete occlusions are often limited by small branches.

OBJECTIVE

We aimed to demonstrate that even in cases where complete occlusion of the AChA aneurysm is complex due to small branches, complete occlusion can be safely achieved using indocyanine green video-angiography and intraoperative neurophysiological monitoring (IONM).

METHODS

We performed a retrospective review of all unruptured AChA aneurysms surgically treated at our institution from 2012 to 2021. All available surgical videos were reviewed to find AChA aneurysms clipped with small branches; clinical and radiological data were collected for these cases.

RESULTS

Among 391 cases of unruptured AChA aneurysms treated surgically, 25 AChA aneurysms were clipped with small branches. AChA-related ischemic complications occurred in 2 cases (8%) without retrograde indocyanine green filling to the branches. These 2 cases had changes in IONM. There were no ischemic complications in the remaining cases with retrograde indocyanine green filling to the branches and no change in IONM. During an average follow-up of 47 months (12-111 months), a small residual neck was observed in 3 cases (12%) and recurrence or progression of the aneurysm was observed in only 1 case (4%).

CONCLUSIONS

The surgical treatment of AChA aneurysms carries the risk of devastating ischemic complications. Even in cases where complete clip ligation seems impossible due to small branches associated with AChA aneurysms, complete occlusion can be safely achieved using indocyanine green video-angiography and IONM.

An anomalous hyperplastic anterior choroidal artery associated with an unruptured internal carotid–posterior communicating artery aneurysm

The anterior choroidal artery (AChA) injuries can result in severe neurologic deficits, so requiring careful observation to avoid inadvertent damage during neuroendovascular procedures. In this case report, we present the unusual case of an anomalous hyperplastic AChA associated with a fetal-type posterior communicating artery (PCoA), and an unruptured internal carotid artery (ICA) –PCoA aneurysm. A 54-year-old woman presented with persistent headache. Brain magnetic resonance imaging (MRI) showed an unruptured cerebral aneurysm in the right ICA, and cerebral angiography revealed a proximal fetal-type PComA and a distal anomalous hyperplastic AChA. Coil embolization was performed with no neurologic deficits and the target lesion was embolized with a total of 6 coils. An anomalous hyperplastic AchA has a lengthy course with numerous choroidal and perforating branches, and therefore, an abundant perfusion region. Thorough knowledge of the development and anatomy of anomalous arteries is important for safely performing endovascular procedures without causing any ischemic complications.

Ruptured anomalous hyperplastic anterior choroidal artery aneurysm: a case report

A 48-year-old man hospitalized for subarachnoid hemorrhage harbored a ruptured aneurysm arising from an anomalous hyperplastic anterior choroidal artery. Endovascular treatment was performed and the aneurysm was successfully embolized with neck remnant. The anterior choroidal artery is a very important artery supplying critical brain structures in the treatment of intracranial vascular disease. Anomalous hyperplastic anterior choroidal artery is rare, so the embryological perspective is important for its recognition in surgical procedures.