a 66-year - old female was presented to the emergency room with sudden weakness on her left side and dysarthria while taking aspirin .
diffusion weighted magnetic resonance imaging ( mri ) showed several small acute infarctions scattered in her right frontal cortex and basal ganglia .
mr angiography revealed a severe stenosis of the right middle cerebral artery ( mca ) .
digital subtraction angiography ( dsa ) confirmed the severe long segment stenosis of the mca and a significant decrease of flow velocity to the distal segment ( fig .
1a ) . we suspected that her current medical treatment would be ineffective to prevent another stroke , and thus , we planned an endovascular treatment .
an endovascular procedure was performed 1 week later when her left - sided weakness was almost recovered .
she received a daily oral administration of 325 mg of aspirin and 75 mg of clopidogrel before the procedure .
endovascular procedure was performed under local anesthesia and with systemic heparinization . with a 6 fr guiding catheter located in the right internal carotid artery ( ica ) ,
after the microcatheter was advanced across the lesion , the microwire was exchanged with a 300 cm exchange wire that could facilitate balloon and stent navigation .
the microcatheter was removed , and a 1.520 mm gateway balloon catheter was advanced over the exchange wire .
the balloon was located within the stenotic segment and inflated to approximately 6 atm . on control angiogram after balloon angioplasty
next , the wingspan delivery system was prepared and advanced over the exchange wire across the target lesion . during wingspan ( 3.520 mm ) passed cavernous ica , patient complained headache and nausea , and systolic blood pressure was elevated from normal range to approximately 160 mmhg .
immediately , a stent was deployed at the stenotic segment and a control angiogram was achieved .
although the stenotic segment was recanalized and the distal flow restored to normal velocity ( fig .
1b ) , a tiny irregularity of posterior parietal branch of right mca and extravasation of contrast media suggested that dissections were revealed ( fig .
rotational flat panel ct was performed immediately and showed a small amount of extravasation of contrast media within the subarachnoid space along the right lateral sulcus ( fig .
we dropped the blood pressure under normal range and reversed heparin with protamine sulfate . on the angiogram performed
10 minutes later , a small filling defect appeared within the stenosis , which was suspected as ist .
because of a subarachnoid hemorrhage caused by an iatrogenic vessel injury , iib / iiia receptor antagonist or fibrinolytic agent should not be administrated for thrombolysis . to manage the ist
rebar 18 " microcatheter ( ev3 , irvine , ca , u.s.a . ) was passed the wingspan stent , and a solitaire stent ( 420 mm , ev3 , irvine , ca , u.s.a . ) was deployed to cover the wingspan stent ( fig .
ist was completely resolved on dsa obtained at 30 and 60 minutes after procedure ( fig .
brain ct at immediate and 24 hours after procedure did not reveal any new low attenuation or progression of subarachnoid hemorrhage .
in - stent restenosis occurs in approximately 30% of patients after delivery of the wingspan stent , although many of these incidents of re - stenosis remain asymptomatic .
although the actual rate of periprocedural ist of intracranial stent is not obvious , the most recent report demonstrated that the rate of acute or subacute ist after intracranial stent ranged from 10% to 14.6% [ 4 , 6 ] .
contrary to chronic in - stent stenosis , acute ist can result in permanent disability of the patient .
. aspirin and clopidogrel resistance may be the actual causes of ist during the periprocedural period , but it is likely there are other factors that have not been elucidated yet . it should be noted that the incidence of ist in the wingspan and gateway system is more frequent than that in the stent for aneurysm neck remodeling .
the reason can be explained that the underlying disease itself is different from cerebral aneurysms and may be more prone to acute thrombus formation . a balloon angioplasty before the wingspan placement may result in an endothelial injury or the exposure of atheromatous plaque material , promoting an in - stent thrombus formation .
the present case showed that the secondary self - expandable stent had resolved acute ist without a new thrombus formation within the stent in spite of the non - administration of fibrinolytic agents .
the second stent would open circumferentially to displace the thrombus , immediately reestablishing a channel of flow within the occluded vessel .
once antegrade flow was restored , thrombus dissolution via endogenous thrombolysis would follow stent deployment . therefore , we suspected that the etiology of acute ist in our case might be not associated with aspirin or clopidogel resistance but with endothelial injury .
stent in - stent would cover the exposure plaque material from the coagulation system , protecting re - growth of the thrombus within stent .
unfortunately , we were unable to confirm drug resistance using blood assay , such as verifynow p2y12 test .
the management described for the ist includes a systemic or local application of iib / iiia receptor antagonist or a recombinant tissue - type plasminogen activator with / without balloon angioplasty [ 4 , 6 , 8 ] .
although these thrombolytic agents are effective solutions for acute thrombolysis , they can not be used and the mechanical technique should be considered for the recanalization of thrombotic occlusion of artery when there is a recent hemorrhage such as the present case .
we have found several reports regarding the use of stent - in stent technique for recanalization of the late in - stent restenosis following the wingspan placement [ 5 , 8 , 9 ] . however , to the best of our knowledge , this present case is the first case that has recanalized acute ist using a stent in - stent technique and without using the thrombolytics .
iatrogenic vascular perforation is a complication of major concern that can result in fatal intracranial hemorrhages during endovascular neurointervention .
when vascular perforation is detected during a procedure , the treatment should immediately begin with a reversal of anticoagulant , lowering the blood pressure and/or temporary or permanent closure of the ruptured vessel . as in this case ,
when an ist following a wingspan stent placement for intracranial stenosis occurs with a coincidentally hemorrhagic complication , the deployment of another stent in - stent should be considered as a treatment option .
 we presented a case that an acute in - stent thrombosis after the deployment of a wingspan stent was successfully managed with a stent in - stent technique . because vessel perforation and subarachnoid hemorrhage were iatrogenically developed during the procedure , we were unable to use the thrombolytic agents to correct the in - stent thrombosis . 
 when a thrombotic complication following an intracranial stent placement occurs with a coincidentally hemorrhagic complication , the stent in - stent technique should be considered as a treatment option . 