Neurointervention.  2015 Sep;10(2):89-93. 10.5469/neuroint.2015.10.2.89.

Does a Low-wall Coverage Stent Have a Flow Diverting Effect in Small Aneurysms?

• Liu H
• Choe J
• Jung SC
• Song Y
• Yang KH
• Park KJ
• Goo HW
• Park WH
• Suh DC

• KMID: 2148999
• DOI: http://doi.org/10.5469/neuroint.2015.10.2.89

Abstract

BACKBROUND AND PURPOSE: The flow diverting effect of a low-wall coverage stent remains controversial. We evaluted patients who underwent stenting for small aneurysms with a low but potential risk of growth and reviewed related literature.
MATERIALS AND METHODS
We evaluated 9 small aneurysms among 19 unruptured intracranial aneurysms from eight patients who underwent stenting. The patients had unexplainable severe headache (n = 8), aneurysm originating from the anterior choroidal artery (n = 3), potential growth or rupture risks including hypertension (n = 5), and multiple aneurysms (n = 6). Stents with a relatively low-wall coverage ratio (8-10%) were used. Clinical and angiographic outcomes were assessed.
RESULTS
One (n = 8) or two stents (n = 1) were used without any procedural difficulties or complications. Although no immediate changes of aneurysm morphology were observed, aneurysms decreased in size (n = 8) when examined by DSA (n = 8) or MRA (n = 1) during a median 28.9-month follow-up. There were no adverse events, including thromboembolism, aneurysm rupture, or stent movement during a median 31.9-month clinical follow-up (range: 17-69 months).
CONCLUSION
Although a variable degree of aneurysm size decrease may not prevent further growth or rupture of small aneurysms, stenting with a low-wall coverage ratio may have some advantageous hemodynamic effect. Flow modification of stent architecture vs. aneurysm characteristics, including size and location, on long-term outcome, requires further clarification.

Keyword

Stent; Intracranial aneurysm; Hemodynamics

MeSH Terms

Aneurysm*
Arteries
Choroid
Follow-Up Studies
Headache
Hemodynamics
Humans
Hypertension
Intracranial Aneurysm
Rupture
Stents*
Thromboembolism

Figure

• 

  Fig. 1 Comparison of initial and follow-up angiograms for nine aneurysms. Arrows indicate pre-stent aneurysms and arrowheads indicate final post-stent aneurysms on follow-up angiogram.Note: - m = months, listed number of each patient corresponds to the patient list in Table 1.

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