Basilar dolichoectasia and the spontaneous intradural vertebral artery dissection

Intramural Hematoma in Vertebrobasilar Dolichoectasia-Related Stroke: A Retrospective Analysis of Six Consecutive Patients

BACKGROUND

The pathophysiology underlying vertebrobasilar dolichoectasia (VBD) is largely unknown. However, a few reports have demonstrated that acute intramural hematoma (IMH) in VBD is associated with stroke. We aimed to investigate the clinical and radiological features of IMH in VBD and the role of IMH in predicting rupture and patient outcomes.

METHODS

We retrospectively reviewed the medical records of patients treated in 2 stroke centers between January 2012 and December 2021. Patients presenting with VBD and stroke were eligible for study inclusion. We excluded patients with stroke caused by arterial dissection or artery-to-artery embolism. IMH was defined as a crescent-shaped area of high signal density in the vessel wall on axial computed tomography in the absence of an intimal flap, double lumen, and pearl-and-string sign.

RESULTS

Six patients were analyzed. All presented with symptoms of brainstem/cerebellar infarction without headache. Interobserver agreement for the presence or absence of IMH was excellent (100%). IMH was detected in 5 patients. The positive predictive value of IMH for rupture was 80% (95% confidence interval, 28%-99.5%). The median time from symptom onset to rupture was 2.5 days (range, 1.5-4). Median computed tomography values were significantly higher within the IMH than those in the lumen of the basilar artery (70 vs. 44.5 Hounsfield units; P = 0.008). The modified Rankin scale score on day 30 after onset was 5 in 1 patient and 6 in the remaining 5.

CONCLUSIONS

IMH in patients with VBD presenting with brainstem/cerebellar infarction should be regarded as a sign associated with a high risk of rupture.

Melittin-loaded Iron Oxide Nanoparticles Prevent Intracranial Arterial Dolichoectasia Development through Inhibition of Macrophage-mediated Inflammation

Rationale: In intracranial arterial dolichoectasia (IADE) development, the feedback loop between inflammatory cytokines and macrophages involves TNF-α and NF-κB signaling pathways and leads to subsequent MMP-9 activation and extracellular matrix (ECM) degeneration. In this proof-of-concept study, melittin-loaded L-arginine-coated iron oxide nanoparticle (MeLioN) was proposed as the protective measure of IADE formation for this macrophage-mediated inflammation and ECM degeneration. Methods: IADE was created in 8-week-old C57BL/6J male mice by inducing hypertension and elastase injection into a basal cistern. Melittin was loaded on the surface of ION as a core-shell structure (hydrodynamic size, 202.4 nm; polydispersity index, 0.158). Treatment of MeLioN (2.5 mg/kg, five doses) started after the IADE induction, and the brain was harvested in the third week. In the healthy control, disease control, and MeLioN-treated group, the morphologic changes of the cerebral arterial wall were measured by diameter, thickness, and ECM composition. The expression level of MMP-9, CD68, MCP-1, TNF-α, and NF-κB was assessed from immunohistochemistry, polymerase chain reaction, and Western blot assay. Results: MeLioN prevented morphologic changes of cerebral arterial wall related to IADE formation by restoring ECM alterations and suppressing MMP-9 expression. MeLioN inhibited MCP-1 expression and reduced CD68-positive macrophage recruitments into cerebral arterial walls. MeLioN blocked TNF-α activation and NF-κB signaling pathway. In the Sylvian cistern, co-localization was found between the CD68-positive macrophage infiltrations and the MeLioN distributions detected on Prussian Blue and T2* gradient-echo MRI, suggesting the role of macrophage harboring MeLioN. Conclusions: The macrophage infiltration into the arterial wall plays a critical role in the MMP-9 secretion. MeLioN, designed for ION-mediated melittin delivery, effectively prevents IADE formation by suppressing macrophage-mediated inflammations and MMP activity. MeLioN can be a promising strategy preventing IADE development in high-risk populations.

Basilar dolichoectasia with intermural hematoma accompanied by cerebral microbleeds and white matter hyperintensities: A case report

RATIONALE

The clinical manifestations of basilar dolichoectasia (BD) are variable. The diagnosis is based on imaging measurements. Digital subtraction angiography displays only the dilated vascular lumen and lacks visualization of the arterial wall. High-resolution Magnetic resonance imaging (MRI) can identify intramural hematoma; therefore, it may be more suitable for the imaging evaluation of BD. However, most of the existing literature pertaining to BD lacks vascular wall assessment.

PATIENT CONCERNS

A 65-year-old Chinese man perceived weakness of the left upper and lower limb, double vision, dizziness, nausea, and vomiting was admitted to the emergency department. Fifteen years prior to this admission, he began taking levamlodipine besylate inconsistently for hypertension, but the level of blood pressure control was uncertain. The patient's father had a family history of hypertension.

DIAGNOSES

An emergency axial computed tomography scan of the brain showed basilar artery (BA) dilation. Computed tomography angiography further indicated a maximum BA diameter of 38.94 mm. The length was >182 mm. MRI revealed acute infarctions of the right medulla oblongata and pons. Meanwhile, the patient had evidence of cerebral small vessel disease, including cerebral microbleeds and white matter hyperintensities. Whole-exome sequencing eliminated significant genetic variations consistent with clinical phenotypes. BD and intramural hematoma were further confirmed by high-resolution MRI of the arterial wall.

INTERVENTIONS

Atorvastatin was admitted according to the results of the high-resolution MRI of the arterial wall. Benidipine hydrochloride was selected as a long-term anti-hypertensive drug.

OUTCOMES

The patient had no symptoms of neurological damage during 3-month follow-up.

LESSONS

Current evidence shows that BD has no obvious correlation with atherosclerosis. BA dissection and uncontrolled hypertension may be important factors in the progression of BD. BD-related stroke is likely to recur, and there are no standard secondary prevention measures. BD is often accompanied by cerebral microbleeds, and bleeding risk must be assessed during secondary prevention. When the BA diameter is greater than 10 mm, anti-platelet medication should be used with caution, blood pressure should be strictly controlled, and endovascular treatment should be considered.

Medullary Compression Due to Ectatic Vertebral Artery-Case Report and Review of Literature

Medullary compression syndrome due to anomalous course of blood vessels is a rare disease most commonly seen in the adult population. The offending vessels causing this syndrome are mostly posterior inferior cerebellar artery or the vertebral artery. The symptoms of this syndrome vary from most common hypertension to various other neurologic deficits like hemiplegia, dysesthesia, and dysarthria. Intractable dizziness is a rare symptom of this disease. The definite management plan for this disease is microvascular decompression. We present our case of medullary compression syndrome which manifested as intractable dizziness. We describe our experience in the management of this patient as well as present a review of literature of this rare disease.

Why does my patient's basilar artery continue to grow? A four-year case study of a patient with symptoms of vertebrobasilar dolichoectasia

BACKGROUND

Vertebrobasilar dolichoectasia (VBD) is a clinical entity associated with ischemic stroke, compression of cranial nerves or brainstem, and hydrocephalus. There have been relatively few studies following the progression of VBD in patients presenting with a variety of diverse clinical features.

CASE PRESENTATION

Here, we report a case study of a male with progressive VBD who was followed from November 2012 to December 2016. The patient had diagnosed hypertension for several years and suffered from left peripheral facial paralysis, recurrent ischemic attacks in the brainstem and cerebellum, obstructive hydrocephalus and frequent pneumonia. A series of cranial CT and multi-modal MRI scans were performed to explore the brain imaging features of the patient during follow-up.

CONCLUSIONS

The presented case study suggests that aging, uncontrolled hypertension, arterial dissection and infection may contribute to the exacerbation of VBD and recurrent ischemic stroke.