Localized Marked Elongation of the Distal Internal Carotid Artery with or without PHACE Syndrome: Segmental Dolichoectasia of the Distal Internal Carotid Artery

[Pathological tortuosity of intracranial arteries (pure arterial malformation) - diagnosis and management tactics]

BACKGROUND

Tortuosity of intracranial arteries is rare and usually mistaken for arteriovenous malformations. In the world literature, the term «pure arterial malformations» is used to refer to this disease.

OBJECTIVE

To summarize the experience of the Burdenko Neurosurgery Center on diagnosis of intracranial artery tortuosity, management and treatment of these patients, as well as to review appropriate literature data.

MATERIAL AND METHODS

Tortuosity of intracranial arteries was detected in 11 patients (8 women and 3 men) aged 7-48 years who underwent outpatient or inpatient examination and treatment at the Burdenko Neurosurgery Center between 2009 and 2022. We analyzed angiographic, clinical and follow-up data of these patients, as well as appropriate literature data.

RESULTS

According to angiography data, all patients had moderate dilatation, elongation and tortuosity of intracranial arteries without signs of arteriovenous shunting. The most common finding was tortuosity of several segments of internal carotid artery (5 cases). Lesion of PCA, PComA, MCA and ACA was less common. In 7 cases, the walls of the deformed vessels had calcified zones. In two cases, there were saccular aneurysms in the walls of the tortuous vessels. In one case, tortuosity was combined with kinking of the left subclavian artery, in another one - tortuosity of C1 segment of the right ICA. No patient had specific clinical manifestations. The follow-up period was 1-10 years in 7 patients. There were no changes in structure of tortuosity or appearance of new aneurysms.

CONCLUSION

Tortuosity of intracranial arteries is an extremely rare disease with the highest incidence in young women. This abnormality has no specific clinical manifestations and does not require surgical or conservative treatment. Tortuosity of intracranial arteries should be differentiated from arterial dolichoectasia, fusiform aneurysms and AVMs.

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.

Neuroradiological findings in Alagille syndrome

Alagille syndrome (ALGS) is a multisystemic disease caused by mutations in genes of Notch pathway, which regulates embryonic cell differentiation and angiogenesis. Clinically, ALGS is characterized by cholestasis, cardiac defects, characteristic facial features, skeletal and ophthalmologic abnormalities. The aim of this review is to illustrate neuroradiological findings in ALGS, which are less well-known and prevalent, including cerebrovascular anomalies (such as aneurysms, dolichoectasia, Moyamoya syndrome and venous peculiarities), Chiari 1 malformation, craniosynostosis, intracranial hypertension, and vertebral anomalies (namely butterfly vertebra, hemivertebra, and craniocervical junction anomalies). Rarer cerebral midline malformations and temporal bone anomalies have also been described.

Long-term clinical and mid-term radiographic follow-up of pure arterial malformations

BACKGROUND

Pure arterial malformations (PAMs) are rare vascular lesions characterized by dilated, tortuous arterial loops without venous shunting. The natural history of PAMs remains unclear. We report the mid-term radiological and longer-term clinical outcomes of the largest series of patients with PAM.

METHODS

Retrospective review at a tertiary academic referral center for patients with a PAM. Follow-up clinical and radiological data were collected and analyzed for clinical symptoms and radiographic changes.

RESULTS

Twenty-five patients met the inclusion criteria. The mean age at presentation was 30.9 ± 14 years. Nineteen (76%) patients were female, and six (23.1%) were male. Eleven (44%) patients had ≥1 symptom at presentation, of which only 3 (12%) could be linked to PAM. The most common symptom was headache (n=8). PAMs involved a single vessel in 16 (64%) cases and ≥2 vessels in 9 cases (36%). Fifteen (60%) lesions were isolated to the anterior circulation compared to 6 (24%) in the posterior circulation. The most frequently involved vessel was the supraclinoid internal cerebral artery (36%). An associated saccular aneurysm was present in 32% of patients. Ten lesions were partially calcified. The mean radiographic and clinical follow-up was 21.9 ± 26.5 months and 44.6 ± 34.8 months, respectively. None of the patients developed new symptoms related to their lesion or radiographic progression over the duration of follow-up.

CONCLUSIONS

PAMs are found most frequently in young, asymptomatic females. PAMs have a benign natural history and are best managed conservatively with serial imaging.

Dolichoectasia of the internal carotid artery terminus, posterior communicating artery, and posterior cerebral artery: The embryonic caudal ramus internal carotid segmental vulnerability legacy

Dolichoectasia of the distal internal carotid artery, posterior communication artery (PCoA) and posterior cerebral artery is an extremely rare abnormality. Dolichoectasia of the internal carotid artery, PCoA and the P1 segment of posterior cerebral artery can be postulated its pathogenesis by the embryological perspective basis from caudal ramus of the internal carotid artery terminus. The pathogenesis and treatment strategy are not well established. We reviewed and proposed embryological perspective, pathogenesis, clinical setting, radiological findings and management of this rare malformation.

Long segment dolichoectasia of the right internal carotid artery diagnosed by CT angiography

Dolichoectasia of the cerebral artery, a rare disorder of arterial dilatation, elongation, and tortuosity, most frequently involves the vertebrobasilar system in elderly patients with hypertension and is associated with the development of atherosclerosis in the aging process. Dolichoectasia also can be seen in the carotid system, but it is usually seen at the intracranial short segment of the internal carotid artery (ICA) or anterior cerebral artery. We present a case of dolichoectasia of the long segment of the right internal carotid artery that extended from the upper cervical to terminal segment of the vessel that was diagnosed by computed tomography angiography in a normotensive 66-year-old woman with transient ischemic attack.