Cutting Balloon Angioplasty for Carotid In-Stent Restenosis: Case Reports and Review of the Literature Qaisar A. Shah, MD, Alexandros L. Georgiadis, MD, M. Fareed K. Suri, MD, Gustavo J. Rodriguez, MD, Adnan I. Qureshi, MD From the Zeenat Qureshi Stroke Research Center, Department of Neurology, University of Minnesota, Minneapolis, MN (QAS, ALG, MFKS, GJR, AIQ). Keywords: Carotid artery, in-stent restenosis, cutting balloon angioplasty, transluminal angioplasty, carotid stent. Acceptance: Received September 27, 2007, and in revised form September 27, 2007. Accepted for publication November 9, 2007. Correspondence: Address correspon- dence to Qaisar A. Shah, MD, Univer- sity of Minnesota, Department of Neu- rology, MMC 295, 420 Delaware Street SE Minneapolis, MN 55455. E-mail: qaisarshah@gmail.com J Neuroimaging 2008;18:428-432. DOI: 10.1111/j.1552-6569.2007.00225.x ABSTRACT Percutaneous stenting techniques are becoming more commonly used for treatment of carotid artery disease. One outcome of particular concern is in-stent restenosis. Indi- cations for treatment of in-stent restenosis are not clearly defined. Use of traditional balloon angioplasty with or without stent placement is still considered the first option. Cutting balloon angioplasty has recently been used as an alternative treatment option for revascularization of in-stent restenosis with higher procedural success rates and without the use of additional stents. We report our experience with cutting balloon angioplasty in treating 2 patients with carotid in-stent restonosis, and review previous cases reported in the literature. A total of 16 patients have been treated with cutting balloon angioplasty. Among 11 patients for whom the clinical and angiographic information were available, 63% of patients were asymptomatic at the time of treatment, and more than 90% of patients showed either complete angiographic resolution or residual stenosis of less than 30%. Additional stent placement or angioplasty was required in only half of the patients, and 1 patient had recurrent stenosis. The review suggests that the procedure is safe and effective. Introduction In-stent restenosis is an infrequent complication of carotid artery angioplasty and stenting. The rate of in-stent restenosis ranges from 1% to 14% per year. 1,2 Several noninvasive modalities are available to identify in-stent restenosis. Doppler ultrasound is not a very reliable surveillance tool, because of lack of standard criteria and falsely increased peak systolic velocities as a result of changes in arterial compliance secondary to stent placement. Stanziale et al. 3 recommended that to determine ≥70% in-stent stenosis, peak systolic velocity = 350 cm/second and internal carotid artery/common carotid artery ratio ≥4.75 are sensitive criteria; to determine ≥50% stenosis, peak systolic velocity ≥225 cm/ second and internal carotid artery/common carotid artery ra- tio ≥2.5 are required. With wider availability and better un- derstanding of computed tomographic (CT) angiography 4 and magnetic resonance angiography, these technologies are more commonly utilized for evaluation of in-stent restenosis. The value of magnetic resonance imaging can be influenced by the type of the stent used. Stents made of nitinol or tantalum alloy induce less artifact than cobalt and stainless steel stents. 5,6 Currently, there is no standard treatment for in-stent resteno- sis, although different endovascular approaches have been ad- vocated. Percutaneous transluminal angioplasty with our with- out stent placement is presently the most frequent approach, al- though cutting balloon angioplasty, with or without stent place- ment, is being increasingly considered. The literature supports the use of cutting balloon angioplasty for in-stent restenosis, because of procedural advantages. 7-9 The cutting balloons are equipped with atherotomes (microsurgical blades), which are “.005” in height and are bonded longitudinally to the balloon surface, (Fig 1). The length of each atherotome depends on its use in the vessel; it measures between 6 mm and 20 mm in length. The microsurgical blades create longitudinal incisions on the vessel wall, followed by balloon dilation, which expands the artery at the incisions. Recoil tension is reduced by the use of cutting balloons as compared to conventional angioplasty. The luminal gain after cutting balloon angioplasty is achieved by de- creasing the amount of plaque without causing an increase in the total size of the vessel. 7 Cutting balloon angioplasty has advan- tages of using fewer balloon angioplasties, fewer requirements for additional stents, and lower incidence of balloon slippage. 7 We report our experience with cutting balloon angioplasty in 2 patients and subsequently review the literature. Methods The literature review sought to find reports of patients who underwent treatment with cutting balloon angioplasty for in- stent restenosis of the carotid artery. Electronic search terms included: carotid stenosis, in-stent restenosis, and cutting bal- loon angioplasty and the search was performed using the MEDLINE, PubMed, and Cochrane databases from 1990 to 2006. Case Reports Case 1 A 79-year-old woman with history of thyroid cancer under- went neck radiation in 1998. In 2002, she had left internal carotid artery stenting for symptomatic high-grade stenosis. She was diagnosed by carotid ultrasound and magnetic resonance angiography with symptomatic high-grade in-stent restenosis of the left internal carotid artery in 2006. The symptoms 428 Copyright ◦ C 2008 by the American Society of Neuroimaging