Future of Endovascular and Surgical Treatments of Atherosclerotic Intracranial Stenosis

Intracranial atherosclerotic disease and resultant intracranial stenosis is a global leading cause of stroke, and poses an ongoing treatment challenge. Among patients with intracranial stenosis, those with hemodynamic compromise are at high risk for recurrent stroke despite medical therapy and risk factor modification. Revascularization of the hypoperfused territory is the most plausible treatment strategy for these high-risk patients, yet surgical and endovascular therapies have not yet shown to be sufficiently safe and effective in randomized controlled trials. Advances in diagnostic and therapeutic technologies have led to a resurgence of interest in surgical and endovascular treatment strategies, with a growing body of evidence to support their further evaluation in the treatment of select patient populations. This review outlines the current and emerging endovascular and surgical treatments and highlights promising future management strategies.

Persistent Primitive Olfactory Artery Aneurysm

A middle-aged patient presented to the hospital as a high-grade aneurysmal subarachnoid hemorrhage. The patient was treated with endovascular coil embolization of the ruptured basilar tip aneurysm. Angiography also demonstrated multiple other aneurysms including Type I persistent primitive olfactory artery (PPOA) aneurysm. After complete recovery and return to independence the patient underwent elective treatment of the PPOA aneurysm with endovascular placement of a flow diversion stent. Persistent primitive olfactory artery is an extremely rare variant of the anterior cerebral artery with an incidence of 0.14% and a known increased risk of aneurysm formation.

Emergent carotid endarterectomy and mechanical thrombectomy in tandem occlusion

Background:

Acute tandem occlusions, or occlusions of the extracranial portion of the internal carotid artery (ICA) with concurrent thromboembolism of the intracranial ICA or middle cerebral artery, poses a major clinical challenge, with patients suffering worse outcomes compared to those with single occlusions. Management of these lesions generally includes a combination of mechanical thrombectomy (MT) of the intracranial occlusion and stenting of the extracranial carotid lesion. In this manuscript, we describe a successful surgical method for achieving revascularization of tandem occlusions in the rare circumstance that the proximal lesion cannot be crossed endovascularly to gain intracranial access.

Methods:

Despite using our institution’s standard protocol for achieving revascularization of such lesions, the extracranial occlusion could not be crossed endovascularly, and the case was converted to an emergent carotid endarterectomy (CEA) in the operating room. Once the endarterectomy was complete, intraoperative MT was performed before cervical incision closure to revascularization.

Results:

The patient recovered well postoperatively and was discharged with NIHSS of 2 due to minor facial palsy and minor dysarthria. Thirty-day follow-up revealed resolution of the prior neurologic deficits and an mRS of 1.

Conclusion:

Emergent CEA should be considered in the rare circumstance of being unable to cross the cervical occlusion during management of acute ischemic stroke with tandem occlusion.

Cervical carotid occlusion in acute ischemic stroke: Should we give tPA?

Background:

Acute ischemic stroke (AIS) due to cervical internal carotid artery (cICA) occlusion is challenging to treat, with the lower revascularization rates, higher risk for complications, and poor response to thrombolytic therapy compared to isolated intracranial occlusions. While emergent revascularization through mechanical thrombectomy (MT) improves outcomes, the impact of tissue plasminogen activator (tPA) on outcomes in this subgroup of patients remains unclear. The objective of this study is to report our preliminary experience in treating AIS with cICA occlusions secondary to severe atherosclerotic stenosis and to establish the need for further clinical studies to determine the optimal intervention strategy for these lesions.

Methods:

Data were collected on patients who presented with acute cICA occlusion who underwent MT and either acute or staged carotid angioplasty and stenting. We compare patients who received tPA to those who did not, analyzing revascularization times, outcomes, and complications between the two populations, and discuss how this influenced our preferred treatment approach.

Results:

Twenty-one patients met inclusion criteria, seven of who received tPA and 14 did not receive tPA before surgical intervention. Procedural and functional outcomes were similar between the two populations. TPA administration correlated with a higher rate of vessel reocclusion in staged procedures and trended toward higher rates of symptomatic ICH and 90-day mortality.

Conclusion:

Emergent revascularization with acute cICA stenting carries advantages, but its safety is precluded by tPA administration. We suggest a trial which randomizes patients with cICA occlusions to receiving either tPA or dual antiplatelet therapy before surgical intervention, aiming to ultimately improved outcomes in these patients.

Aneurysmal subarachnoid hemorrhage, a presentation of metastatic carcinoma: A case report and review of the literature

Background:

Neoplastic cerebral aneurysms related to metastatic processes are exceptionally rare and carry a dismal prognosis. Only four previous reports exist of neoplastic aneurysms secondary to metastatic adenocarcinoma, all of which were found to be lung cancer in origin. We present the fifth reported metastatic adenocarcinomatous cerebral aneurysm, and the first case is secondary to a non-lung cancer primary.

Case Description:

The patient presented with complaining of headache and was found to have a large right-sided intraparenchymal hemorrhage and smaller left-sided hemorrhage on head CT, and CTA revealed a vascular pouch in the region of the hemorrhage. The patient showed sudden neurologic decline, and repeat imaging revealed enlargement of the hematoma with significant brain compression. The patient underwent emergent angiography revealing a distal cortical middle cerebral artery aneurysm, suspicious for mycotic etiology, which was treated through microsurgical excision at the time of hematoma evacuation. The aneurysm specimen was sent for cultures and pathology, revealing the diagnosis of metastatic non-small-cell carcinoma. Further inpatient workup did not reveal the primary neoplastic source.

Conclusion:

Although diagnostic workup should search for more common pathologic mimics than metastatic neoplastic cerebral aneurysms, clinicians must be able to recognize and expeditiously treat this devastating lesion. Further investigation and analysis of treatment options are necessary to better understand this rare pathology and improve patient outcomes.

Noninvasive evaluation of craniovertebral junction instability in 2 patients following Chiari decompression with rigid C-collar immobilization: illustrative cases

BACKGROUND

The complex Chiari malformation has been identified in a subset of Chiari patients at higher risk for worsening symptoms following Chiari decompression. Although parameters such as the clivoaxial angle and the perpendicular distance of the dens to the line from the basion to the inferoposterior part of the C2 body (pBC2) have been evaluated to help with the prediction of risk, the decision to pursue an occipitocervical fusion in lower-risk patients does not come without inherent risk.

OBSERVATIONS

The authors present 2 patients who had symptoms of worsening ventral brainstem compression following Chiari decompression, neither of whom was categorized in the highest risk category for occipitocervical instability. In addition, neither patient had gross instability on radiographic imaging. A trial with rigid C-collar immobilization provided relief of symptoms in both patients and allowed reassurance of the likelihood of success of occipitocervical fusion.

LESSONS

In patients without clear radiographic instability following Chiari decompression, a C-collar trial may provide a noninvasive option for assessing the potential success of occipitocervical fusion.

En Plaque Meningiomas: A Narrative Review

Background  En plaque meningiomas are a rare subtype of meningiomas that are frequently encountered in the spheno-orbital region. Characterized by a hyperostotic and dural invasive architecture, these tumors present unique diagnostic and treatment considerations. Objective  The authors conduct a narrative literature review of clinical reports of en plaque meningiomas to summarize the epidemiology, clinical presentation, diagnostic criteria, and treatment considerations in treating en plaque meningiomas. Additionally, the authors present a case from their own experience to illustrate its complexity and unique features. Methods  A literature search was conducted using the MEDLINE database using the following terminology in various combinations: meningioma , meningeal neoplasms, en plaque , skull base , spheno-orbital, and sphenoid wing . Only literature published in English between 1938 and 2018 was reviewed. All case series were specifically reviewed for sufficient data on treatment outcomes, and all literature was analyzed for reports of misdiagnosed cases. Conclusion  En plaque meningiomas may present with a variety of symptoms according to their location and degree of bone invasion, requiring a careful diagnostic and treatment approach. While early and aggressive surgical resection is generally accepted as the optimal goal of treatment, these lesions require an individualized approach, with further investigation needed regarding the role of new therapies.

Iatrogenic cortical pseudoaneurysm following ventriculoperitoneal shunt insertion presenting with intraventricular hemorrhage

Background:

Cerebral pseudoaneurysm formation associated with ventricular catheterization is an exceedingly rare complication that results from direct catheter-induced injury to a vessel. We report a case of intracerebral pseudoaneurysm formation associated with ventricular catheterization in a patient with hydrocephalus following aneurysmal subarachnoid hemorrhage.

Case Description:

The patient presented with aneurysmal subarachnoid hemorrhage and underwent partial endovascular embolization of the offending wide-necked basilar tip aneurysm with the plan for a Stage 2 stent-assisted coiling after initial recovery. Before discharge, a ventriculoperitoneal shunt (VPS) was placed for postaneurysmal hydrocephalus. Three weeks later, she presented with intraparenchymal and intraventricular hemorrhage. Angiography revealed a cortical aneurysm contiguous to the ventricular catheter of the VPS. She underwent microsurgical excision of the aneurysm, and a new VPS was placed after resolution of the intraventricular hemorrhage. She later underwent the second stage of the treatment and had an excellent neurological recovery to an independent state.

Conclusion:

Iatrogenic intracerebral pseudoaneurysm formation is an exceedingly rare complication of ventricular catheterization but is associated with significant mortality. Identifying a pseudoaneurysm in this context warrants prompt and definitive treatment with microsurgical or endovascular treatment.