Spontaneous Thrombosis of the Pseudoaneurysm of Right SCA after an Attempt at Embolisation. A Case Report

Abstract

Spontaneous thrombosis of intracranial aneurysms rare, mostly affecting giant aneurysms with narrow necks. We present the case of 34 y/o man with pseudoaneurysm that developed in the course of SAH. The initial CT scan showed an isolated, well-defined hematoma within the right cerebellar hemisphere, digital subtraction angiogram (DSA) performed in a regional hospital showed an irregular shaped aneurysm of the distal segment of the right SCA. The patient was sent to our department, where diagnostic DSA, performed before embolisation revealed an entirely different morphology of the aneurysm. It became larger, round and no other functional branches distal to it were found (picture of "a balloon on a string"). During supraselective catheterization, when microcatheter and microguidewire were already in the right SCA a technical problem of our angio-machine occurred, so the intervention had to be postponed. A week later, a second attempt at embolisation was made. This time an initial DSA showed a lack of filling of the aneurysm sac and thrombosis of the main trunk of the right SCA. The patient remained clinically stable. He was discharged from our hospital five days later.

Figure 1

A) Initial left VA angiogram (AP view) performed 24 hours after SAH. Severe disseminated vasospasm is seen as well as an irregularly shaped aneurysm in the distal portion of the right SCA. B) CT scan performed 4 days after admission to our hospital. Regular, hyperdense round structure representing the right SCA pseudoaneurysm is seen on the right side of posterior fossa.

Figure 2

A) Right VA diagnostic angiogram (AP view). Large, round aneurysm located at the end of the right SCA (“balloon on a string”). No filling of any distal branches of the SCA. B) Embolisation procedure - “road-mapping”. The tip of microcatheter placed in the aneurysmal sac.

Figure 3

A) Right VA diagnostic angiogram (AP view) - one week after failed intervention. The pseudoaneurysm is not displayed. The distal part of the right SCA is not filling either. B) Control CT scan shows hypodensity of the lesion which confirms the thrombosis of the sac of the pseudoaneurysm.