Iatrogenic Middle Cerebral Artery Ruptured Pseudoaneurysm Successfully Treated With a Pipeline Embolization Device

Flow diversion of a middle cerebral artery pseudoaneurysm secondary to a gunshot wound: A case report

Pseudoaneurysms are rare but devastating complications of penetrating head traumas. They require rapid surgical or endovascular intervention due to their high risk of rupture; however, complex presentations may limit treatment options. Our objective is to report a case of severe vasospasm, flow diversion, and in-stent stenosis complicating the treatment of a middle cerebral artery pseudoaneurysm following a gunshot wound. A 33-year-old woman presented with multiple calvarial and bullet fragments within the right frontotemporal lobes and a large right frontotemporal intraparenchymal hemorrhage with significant cerebral edema. She underwent an emergent right hemicraniectomy for decompression, removal of bullet fragments, and evacuation of hemorrhage. Once stable enough for diagnostic cerebral angiography, she was found to have an M1 pseudoaneurysm with severe vasospasm that precluded endovascular treatment until the vasospasm resolved. The pseudoaneurysm was treated with flow diversion and in-stent stenosis was found at 4-month follow-up angiography that resolved by 8 months post-embolization. We report the successful flow diversion of an middle cerebral artery (MCA) pseudoaneurysm complicated by severe vasospasm and later in-stent stenosis. The presence of asymptomatic stenosis is believed to be reversible intimal hyperplasia and a normal aspect of endothelial healing. We suggest careful observation and dual-antiplatelet therapy as a justified approach.

Iatrogenic pseudoaneurysm rupture of the middle cerebral artery after an intracranial pressure monitor placement: a case report and literature review

Thalamic hemorrhage (TH) is a devastating disease with a high mortality rate; however, no specific form of therapy has been proven to reduce mortality. Patients with hemorrhagic stroke undergo intracranial pressure (ICP) monitoring. However, cases involving pseudoaneurysms caused by ICP monitoring in patients with intracerebral hemorrhage have not been reported previously. Here, we report a case of pseudoaneurysm caused by an ICP monitor that was fitted due to hypertensive cerebral hemorrhage.

An off-label use of flow-diverter stent as a successful treatment of a postoperative middle cerebral artery pseudoaneurysm

A pseudoaneurysm or false aneurysm is the result of the disruption of the vessel wall and the formation of a hematoma in communication with the vascular lumen, restrained by perivascular connective tissue. Intracranial pseudoaneurysms represent a rare entity mainly because of trauma, iatrogenic causes, infectious disease, radiation exposure, connective tissue disease and sometimes spontaneous occurrence. We present a 35-year-old female patient with a history of multiple low-grade glioma debulking surgeries. During the last procedure, laceration of the left middle cerebral artery (MCA) occurred with diffuse subarachnoid hemorrhage. Imaging studies showed the formation of a pseudoaneurysm of the left MCA which was successfully treated with the implantation of a flow diverter across the lesion neck and excellent mid- to long- term results. Flow diverter implantation may be a promising technique for the therapeutic management of cerebral pseudoaneurysms.

Neurointerventional management of cerebrovascular trauma

Traumatic cerebrovascular injuries following blunt or penetrating trauma are common and carry a high risk of permanent disability or death. Proper screening, diagnosis, and treatment of these lesions is essential to improve patient outcomes. Advances in imaging continue to improve the accuracy of non-invasive diagnosis of these injuries while new clinical data provide better evidence for optimal management, whether medical or invasive. Here, we review screening, diagnosis, and treatment of traumatic cerebrovascular injuries.

Reduced M2 macrophages and adventitia collagen dampen the structural integrity of blood blister-like aneurysms and induce preoperative rerupture

Objective

Blood blister–like aneurysms (BBAs) are extremely rare aneurysms. They are predisposed to preoperative rerupture with a high case‐fatality rate. Here, we attempt to interrogate the distinct clinicopathology and the histological basis underlying its clinical rerupture.

Methods

Three middle meningeal arteries, 11 BBA (5 reruptured, 6 non‐rerupture) and 19 saccular aneurysm samples were obtained for histopathological investigation. Three reruptured BBAs, 3 non‐reruptured BBAs and 6 saccular (3 ruptured, 3 unruptured) aneurysms were obtained for quantitative flow cytometry analysis.

Results

Compared with true saccular aneurysms, the BBA aneurysm wall lacks arterial stroma cells including CD31+ endothelial cells and α‐SMA + smooth muscle cells. Only fibroblasts and adventitial collagen were observed in the BBA aneurysm wall. Meanwhile, BBAs were enriched with infiltrated inflammatory cells, especially polarized macrophages. Based on the rerupture status, those reruptured BBAs showed drastically reduced fibroblasts and adventitia collagen. Moreover, M2‐polarized macrophages were observed dominant in BBAs and exhibit repairing cellular functions based on their interplays with arterial fibroblasts. Reduced M2 macrophages and arterial tissue repairing modulation may be responsible for the decreasing collagen synthesis and fibrosis repairment, which potentially dampens the aneurysm integrity and induces BBA aneurysm reruputre.

Conclusions

BBAs poses histopathological features of occult pseudoaneurysms or dissecting aneurysms. Reduced M2 macrophages and adventitia collagen may dampen the structural integrity of BBAs and induce preoperative rerupture.

Neurointerventional management of cerebrovascular trauma

Traumatic cerebrovascular injuries following blunt or penetrating trauma are common and carry a high risk of permanent disability or death. Proper screening, diagnosis, and treatment of these lesions is essential to improve patient outcomes. Advances in imaging continue to improve the accuracy of non-invasive diagnosis of these injuries while new clinical data provide better evidence for optimal management, whether medical or invasive. Here, we review screening, diagnosis, and treatment of traumatic cerebrovascular injuries.