HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

Correspondence to:

ARTICLES: W. J. Jiang, T. Srivastava, F. Gao, B. Du, K. H. Dong, and X. T. Xu Perforator stroke after elective stenting of symptomatic intracranial stenosis Neurology 2006; 66: 1868-1872 [Abstract] [Full text] [PDF]

Correspondence: Submit a response to this article

Correspondence published:

Perforator stroke after elective stenting of symptomatic intracranial stenosis

Thomas W. Leung, Henry Mak, Simon C.H. Yu, Ka-sing Wong   (7 November 2006)

Reply from the Authors

Wei-Jian Jiang, Feng Gao   (7 November 2006)

Perforator stroke after elective stenting of symptomatic intracranial stenosis 7 November 2006
Thomas W. Leung, Prince of Wales Hospital, The Chinese Unviersity of Hong Kong Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong, Henry Mak, Simon C.H. Yu, Ka-sing Wong Send Correspondence to journal: Re: Perforator stroke after elective stenting of symptomatic intracranial stenosis drtleung{at}cuhk.edu.hk Thomas W. Leung, et al.	Branch vessel occlusion by snow plowing effect and jailing has been a concern in intracranial stenting. Jiang et al [1] reported a low rate of perforator stroke (3.0%) by coronary balloon-mounted stents. However, the figure could be an underestimate as CT rather than MRI was used for diagnosis. The Editorial [2] in the same issue described the current trend of using self-expanding stent (Wingspan) in intracranial vasculature. The system allows submaximal balloon dilatation which may reduce the risk of acute perforator occlusion. It is unclear whether the subsequent luminal gain of the parent artery through the sustained radial force of the self-expanding stent will lead to sub-acute jailing or occlusion of the perforators. In our center, paired MRI (pre- and post-stenting) was obtained to look for new infarcts in the perforator zone of the treated artery in patients who had angioplasty by Wingspan system. The post-stenting MRI was performed 4 months after the procedure. Among the six patients who had stenting at the perforator-rich arteries (M1 middle cerebral artery or basilar artery), none had clinical stroke or new infarcts evident on T2-weighted images in the immediate perforator zone. Reference 1. Jiang WJ, Srivastava T, Gao F, Du B, Dong KH, Xu XT. Perforator stroke after elective stenting of symptomatic intracranial stenosis. Neurology 2006; 66:1868-1872. 2. Levy EI, Chaturvedi S. Perforator stroke following intracranial stenting: A sacrifice for the greater good? Neurology 2006; 66:1803-1804. The Editorialists had the opportunity to respond to this Correspondence but declined. Disclosure: The authors report no conflict of interest.
Reply from the Authors 7 November 2006
Wei-Jian Jiang, Beijiang Tiantan Hospital, The Capital University of Medical Sciences No.6 Tiantan Xili, Beijing 100050, China, Feng Gao Send Correspondence to journal: Re: Reply from the Authors cjr.jiangweijian{at}vip.163.com Wei-Jian Jiang, et al.	We thank Leung et al for the interest in our recent article. [1] There is a conceptual difference between stroke and infarct. In our article and other studies, [3,4] ischemic stroke was diagnosed according to the clinical definition: an acute onset of a focal neurologic deficit lasting 24 hours or more specifically attributable to a cerebrovascular distribution. In our series, 6 of 169 patients developed procedure-related ischemic stroke which was diagnosed by an experienced stroke neurologist. One stroke was related to a new cortical infarct distal to the target lesion that was categorized as embolic stroke. The other five ischemic strokes were accordant with diagnosis of perforator stroke. The rate of perforator stroke (3.0%) in our report may not be underestimated. However, infarct is a diagnosis on the basis of the neuroimaging and some of infarcts may be clinically silent. We mentioned that the lack of postoperative MRI may have underestimated the number and size of perforator infarcts [1] instead of perforator stroke. Submaximal balloon dilatation and the use of the Wingspan stent (a self- expanding intracranial stent not currently available in mainland China) may be theoretically be helpful in reducing the risk of perforator occlusion. [2] This inference needs to be confirmed in a large case series as perforator stroke did not occur in our initial 40 patients with middle cerebral arterial stenosis treated with balloon-expandable stent [5] but does occur with increasing cases. [1] As Leung et al mention, whether the sustained radial force of the self-expanding stent can lead to subacute occlusion of the perforating arteries also needs be confirmed in large case series. Nevertheless, treatment with the Wingspan stent does have some advantages over the balloon-expandable steel stent including that patients can undergo MRI examination. Postoperative MRI such as diffusion-weighted or fluid attenuated inversion recovery imaging can increase detection of acute or subacute perforator infarct and therefore can improve the estimation accuracy of the perforator infarct rate resulting from stenting. References 3. Chimowitz MI, Lynn MJ, Howlett-Smith H, et al. Comparison of warfarin and aspirin for symptomatic intracranial arterial stenosis. N Engl J Med. 2005; 352:1305¨C1316. 4. Kasner SE, Chimowitz MI, Lynn MJ et al on behalf of the Warfarin Aspirin Symptomatic Intracranial Disease Trial Investigators. Predictors of ischemic stroke in the territory of a symptomatic intracranial arterial stenosis. Circulation; 2006;113:555-563. 5. Jiang WJ, Wang YJ, Du B, et al. Stenting of symptomatic M1 stenosis of middle cerebral artery: an initial experience of 40 patients. Stroke 2004; 35:1375. Disclosure: The authors report no conflicts of interest.