Posterior communicating and anterior communicating arteries on pre-thrombectomy computed tomography scans are associated with good outcomes irrespective of leptomeningeal collateral status

BACKGROUND

Collateral blood flow is known to be an important factor that sustains the penumbra during acute stroke. We looked at both the leptomeningeal collateral circulation and the presence of anterior and posterior communicating arteries to determine the factors associated with good outcomes and mortality.

METHODS

We included all patients with acute ischaemic stroke in the anterior circulation, who underwent thrombectomy with the same thrombectomy device from 2013 to 2016. We assessed the leptomeningeal circulation by the Tan, Miteff and Maas validated scoring systems on pre-treatment computed tomographic angiography scans and looked at collateral flow through anterior and posterior communicating arteries. The results were good functional outcomes at 3 months (modified Rankin scale 0-2) and mortality.

RESULTS

A total of 147 consecutive acute stroke patients treated with the Embotrap device were included with a median National Institutes of Health stroke scale of 15 (range 2-26). On multivariate analysis only younger age (odds ratio (OR) 0.96/year, 95% confidence interval (CI) 0.94-0.99, P = 0.026), lower National Institutes of Health stroke scale score (OR 0.87/point, 95% CI 0.80-0.93, P < 0.001), number of attempts (OR 0.80/attempt, 95% CI 0.65-0.99, P = 0.043) and the presence of a patent anterior communicating artery (OR 14.03, 95% CI 1.42-139.07, P = 0.024) were associated with good functional outcomes. The number of attempts (OR 1.66/attempt, 95% CI 1.21-2.29, P = 0.002) was significantly associated with mortality and the presence of a patent posterior communicating artery (OR 0.098, 95% CI 0.016-0.59, P = 0.011) was inversely associated with mortality.

CONCLUSIONS

Our study shows that the presence of anterior and posterior communicating arteries is significantly associated with good functional outcomes and reduced mortality, respectively, independent of the leptomeningeal circulation status.

Junctional Chiasmatic Syndrome Due to Large Anterior Communicating Artery Aneurysm

Even though aneurysm involving the anterior communicating artery (A Com A) was common in clinical practice, producing compressive symptoms such as visual loss was rare. We report a case, in which patient had gradually progressive visual loss with features of the junctional chiasmatic syndrome, imaging revealed partially thrombosed large A Com A aneurysm. Intraoperatively, aneurysm was found compressing the optic chiasm and right optic nerve, following clipping and decompression of the optic nerve and chiasm there was gradually improvement in the vision over 2 weeks postoperatively.

De novo giant A2 aneurysm following anterior communicating artery occlusion

BACKGROUND

De novo intracranial aneurysms are reported to occur with varying incidence after intracranial aneurysm treatment. They are purported to be observed, however, with increased incidence after Hunterian ligation; particularly in cases of carotid artery occlusion for giant or complex aneurysms deemed unclippable.

CASE DESCRIPTION

We report a case of right-sided de novo giant A2 aneurysm 6 years after an anterior communicating artery (ACoA) aneurysm clipping. We believe this de novo aneurysm developed in part due to patient-specific risk factors but also a significant change in cerebral hemodynamics. The ACoA became occluded after surgery that likely altered the cerebral hemodynamics and contributed to the de novo aneurysm. We believe this to be the first reported case of a giant de novo aneurysm in this location. Following parent vessel occlusion (mostly of the carotid artery), there are no reports of any de novo aneurysms in the pericallosal arteries let alone a giant one. The patient had a dominant right A1 and the sudden increase in A2 blood flow likely resulted in increased wall shear stress, particularly in the medial wall of the A2 where the aneurysm occurred 2 mm distal to the A1-2 junction.

CONCLUSION

ACoA preservation is a key element of aneurysm surgery in this location. Suspected occlusion of this vessel may warrant closer radiographic follow-up in patients with other risk factors for aneurysm development.