LETTER TO THE EDITOR - VASCULAR
Surgical treatment of posterior inferior
cerebellar artery aneurysms
Received: 8 June 2017 /Accepted: 10 July 2017 / Published online: 24 July 2017
Springer-Verlag GmbH Austria 2017
I read with interest the recent article entitled BPartial wrap-
clipping of the entrance of the pseudolumen of a fusiform
aneurysm in the posterior inferior cerebellar artery: a technical
note^ by Motoyama et al. . The authors reported their ex-
perience using a partial wrap-clipping technique in treating a
fusiform aneurysm in the posterior inferior cerebellar artery
(PICA). They concluded the wrap-clip technique for oblitera-
tion of the entrance into a pseudolumen is one of alternatives
for dissecting fusiform aneurysms of the PICA. However, I
felt uncertain about a few issues.
First, the nature of this lesion was uncertain. The diagnosis
of dissecting aneurysm was often based on the characteristic
features demonstrated on conventional angiography. Previous
studies have demonstrated that dissection was diagnosed if the
lesion showed irregular fusiform dilation with or without as-
sociated narrowing of the PICA [3, 4]. However, besides dis-
section, other possible causes of fusiform aneurysms include
atherosclerosis, collagen disease or unknown factors.
Advanced atherosclerotic arteries have a slightly fusiform
shape . Moreover, MR imaging techniques are now replac-
ing conventional angiography as the criterion standard for the
diagnosis of arterial dissections because of the actual demon-
stration of the intramural hematoma. However, detailed MR
imaging was not carried out before the operation in this study.
Besides basi-parallel anatomical scanning (BPAS) MRI, high-
resolution MR imaging may be a useful diagnostic tool for
dissection. Intramural hematomas, intimal flaps and the
double-lumen sign were recognized as the characteristic fea-
tures of dissection by high-resolution MRI . In addition,
high-resolution MRI provided direct visualization of the ves-
sel wall and differentiated dissection from atherosclerosis .
Thus, further discussion is needed to make a precise diagnosis
of a dissecting fusiform aneurysm.
Second, the treatment strategy for this lesion remains con-
troversial. The unruptured fusiform aneurysm was located in
the proximal segment of the PICA. Open surgery was associ-
ated with a high incidence of lower cranial nerve deficits.
Endovascular treatment offers a less invasive alternative to
open surgery. Recently, the use of a reconstructive technique
with the LVIS Jr. stent hass become feasible and effective for
the treatment of PICA dissecting aneurysms . If there is an
acute angle between the origin of PICA and the VA, retrograde
stenting through the contralateral VA might be used. In our
opinion, assisted coiling using the LVIS Jr. stent might have
been better for this patient.
Third, further long-term follow-up is needed to evaluate the
durability and efficacy of this technique. The wrap-clipping
technique has been shown to be feasible and safe for
unclippable fusiform aneurysms . Although the wrapped
aneurysm mostly disappeared or remained stationary, this mo-
dality is challenging in fusiform dissecting aneurysms involv-
ing long segments. In addition, this modality cannot definitely
occlude the aneurysm and thus cannot completely prevent
rebleeding. If PICA aneurysms are incorporated in the origin
of perforating arteries, the ideal treatment modality is proxi-
mal occlusion or trapping with revascularization.
* Qiangbo Sui
Department of Neurosurgery, Weihai Central Hospital, The Affiliated
Hospital of Weifang Medical College, No. 3 MiShan Dong Road,
Wendeng District, Weihai 264400, China
Acta Neurochir (2017) 159:1653–1654