Outcome of Endovascular Treatment in Symptomatic Intracranial Vascular Stenosis

Objective

The outcome evaluation for the revascularization of intracranial vascular stenoses has not been fully described due to the highly technical nature of the procedure. We report here on the early and late clinical outcomes of angioplasty and/or stenting of symptomatic severe intracranial vascular stenoses at a single institute.

Materials and Methods

Since 1995, we have treated 35 patients with symptomatic intracranial vascular stenosis (more than 70% stenosis, mean stenosis: 78.6% ± 6.2%). Angioplasty (n = 19) was performed for the horizontal segment of the middle cerebral artery (M1) (n = 16) and the basilar artery (BA) (n = 1), the intradural vertebral artery (VA) (n = 1), and the cavernous internal carotid artery (ICA) (n = 1). Stenting (n = 16) was performed for the cavernous or petrous ICAs (n = 9), the intradural VA (n = 3), BA (n = 2), and M1 (n = 2) artery. We assessed the angiographic success (defined as residual stenosis < 50%) rate, the periprocedural complications during the 30-day periprocedural period, the symptomatic recurrence and restenosis during a mean 22-month follow-up (FU) period. The Kaplan-Meier estimate of the cumulative event-free rate of the major cerebrovascular events, i.e. death, stroke or restenosis, was also done.

Results

Angiographic success was achieved in 97% of our patients (34/35). There were four procedure-related complications (11%) including a death and a minor stroke. During the mean 22-month FU, the asymptomatic restenosis rate was 9% and the symptomatic restenosis rate was 6% in the target lesion and 9% in all the vascular territories. The Kaplan-Meier estimate was 70.6% (95% confidence interval = 46.5-94.7) after 33 months of FU.

Conclusion

In addition to a high angiographic success rate and an acceptable periprocedural complication rate, intracranial angioplasty and/or stenting revealed a relatively low symptomatic recurrence rate. Hemorrhage is a rare, but the physician must aware that potentially fatal periprocedural complications can occur.     

Wingspan stent-assisted coiling of intracranial aneurysms with symptomatic parent artery stenosis: experience in 35 patients with mid-term follow-up results

Background

There is a potential risk of aneurysm rupture after parent artery revascularization because of increased blood flow. The purpose of this study is to assess the efficacy and safety of Wingspan stent-assisted coil embolization in the treatment of intracranial aneurysms with symptomatic parent artery stenosis.

Methods

Thirty-five consecutive patients (19 men, 16 women; age range, 48–79 years; mean age, 60.4 years) harboring 35 unruptured wide-necked or fusiform intracranial aneurysms (mean size 6.8 mm; range 2.5–18 mm.) with symptomatic parent artery stenosis (mean degree 71.1%; range 50–92%) were treated with the Wingspan stent-assisted coiling. Twenty-four lesions were located in the anterior circulation and eleven in the posterior circulation. Patients were premedicated with antiplatelet therapy consisting of aspirin 300 mg and clopidogrel 75 mg for at least 3 days before the procedure. Following pre-dilatation and stent placement, a coiling microcatheter entered the aneurysm through the interstices of the stent, and then coiling was performed. After the procedure, clopidogrel 75 mg daily was recommended for an additional 30 days, and aspirin 100 mg was recommended throughout follow-up. For all patients, clinical follow-up was conducted by clinic visitation, or telephone interview. Angiographic follow-up with DSA was recommended at 6 months and 1 year after the procedure. Angiography follow-up (mean time 10.6 months) was obtained in 31 cases (88.6%). The technical feasibility of the procedure, procedure-related complications, angiographic results, clinical outcome and follow-up angiography were evaluated.

Results

In every case, technical success was achieved. The degree of stenosis was reduced from 71.1% to 17.4% after balloon angioplasty and stenting. Immediate angiography demonstrated complete occlusion in 25 cases (71.4%), neck remnant in 7 cases (20.0%), and incomplete occlusion in 3 cases (8.6%). Procedure-related morbidity occurred in two patients (5.7%), including thromboembolism (n = 1) and occlusion of small penetrating arteries (n = 1). At follow-up (mean time 18.3 months), two additional cases of ischemic stroke occurred. The overall frequency of any stroke, intracranial hemorrhage, or death within 30 days or ipsilateral stroke beyond 30 days was 11.4%. No rehemorrhage of treated aneurysm occurred. At angiographic follow-up, four cases demonstrated ≥50% in-stent restenosis (12.9%), one of which was symptomatic, and two aneurysms (6.4% of the follow-up angiograms) demonstrated recanalization.

Conclusion

We found that the Wingspan stent-assisted coil embolization was helpful in the treatment of intracranial aneurysms with parent artery stenosis.     

Preliminary findings of recanalization and stenting for symptomatic vertebrobasilar artery occlusion lasting more than 24 h: A retrospective analysis of 21 cases

Purpose

To evaluate the technical feasibility, safety and short-term treatment effects of recanalization and stenting for intracranial symptomatic vertebrobasilar artery occlusion (VBAO) lasting more than 24 h.

Methods and materials

Twenty-one consecutive patients with VBAO refractory to aggressive medical treatment were enrolled into this study and underwent recanalization and stenting. The rate of recanalization was evaluated radiographically and the functional outcome was examined using modified Rankin Scale (mRS) scores.

Results

Median time between imaging-documented occlusion and endovascular recanalization was 10.5 days (IR, Interquartile Range: 6.5–18); technique success ratio of recanalization was 95.2%. There were 3 periprocedural complications. Median mRS score was 4 (IR, 2.5–5) prior to procedure and 4 (IR, 1–5) at discharge (P < 0.05). One stroke and one death occurred within 30 days after recanalization. Mean duration of clinical follow-up was 15.5 months. One transient ischemic attack, one stroke and one death occurred beyond 30-day window. Mean angiographic follow-up was 10.6 months in 10 patients. Four patients developed in-stent restenosis or occlusion, and two of them were symptomatic. Subgroup analyses revealed better functional recovery (lower mRS) in patients with vertebral artery occlusion (VAO) (P < 0.05).

Conclusions

Endovascular recanalization and stenting for symptomatic VBAO lasting more than 24 h were technically feasible and patients with VAO benefited from the treatment with significant functional recovery. However, the complexity of the procedure and high risk of complication should prompt extreme caution.     

High resolution MR imaging in patients with symptomatic middle cerebral artery stenosis

Purpose

High resolution magnetic resonance imaging (HRMRI) has been used as an imaging modality to depict the intracranial artery wall. The aim of this study was to compare images of the vessel wall between symptomatic and asymptomatic atherosclerotic plaques of the middle cerebral artery (MCA) using HRMRI.

Materials and methods

From September 2009 to August 2010 we prospectively screened consecutive patients for MCA stenosis using time-of-flight (TOF) MR angiography. We studied 14 patients with symptomatic MCA stenosis and 16 patients with asymptomatic MCA stenosis. The HRMRI protocol included three different scans: T1-, T2-, and proton density (PD)-weighted black blood MRI. The cross-sectional images of the MCA wall on HRMRI were compared between the two groups based on the degree of stenosis, remodeling ratio, outward or inward remodeling, plaque signal intensity, plaque surface irregularity, and presence of an intact inner wall.

Results

The degree of MCA stenosis and the ratio of plaque thickening to patent lumen in the symptomatic group were significantly higher than in the asymptomatic group. Outward remodeling of the stenotic area in symptomatic group was significantly higher than that seen in the asymptomatic group, and the reverse was true for inward remodeling of the stenotic area (it was significantly higher in the asymptomatic group compared to the symptomatic group). T2- and PD-weighted high signal foci, eccentric wall thickening, and plaque volume in the stenotic area were all similar between the two groups.

Conclusions

HRMRI has the potential to distinguish between atherosclerotic plaques in symptomatic and asymptomatic MCA stenoses.     

Wingspan stent for symptomatic M1 stenosis of middle cerebral artery

Objective

Stent placement for intracranial atherosclerotic stenosis has become an alternative treatment technique; however, stent placement for middle cerebral artery (MCA) stenosis remains a technical and clinical challenge. Our purpose was to assess the safety and feasibility of Wingspan stent for patients with symptomatic M1 stenosis, and its initial effect on prevention of ischemic events.

Methods

Fifty-three cases with recurrent symptomatic MCA stenosis resistant to medical therapy treated by self-expanding stent were reviewed retrospectively (average 58 ± 18.5 years old, 19 women). All patients underwent angioplasty and stenting with the Gateway balloon–Wingspan stent system, and advised follow-up with DSA or TCD at 6th month.

Results

Patients had an average stenosis ratio of 76.5 ± 15.4% prior to the treatment. Of the 53 patients, the technical success rate was 98.1% as a whole (52/53). The mean degree of stenosis reduced from (76.5 ± 15.4)% to (18.2 ± 11.3)%. Complications associated with the procedure include subarachnoid hemorrhage (1.89%) and occlusion (3.78%) occurred. During a follow-up of 6 months, there was no recurrence of transient ischemic attack or stroke in 52 cases with successful stenting. Cerebral hemodynamics of MCA using transcranial Doppler monitoring were at normal level (<120 cm/s) in 41 follow-up patients. The follow up angiography at 6 month post-procedure was conducted in 32 patients and showed good patency in stented vessels.

Conclusions

Wingspan stent for symptomatic stenosis of middle cerebral artery is a safe and feasible procedure. It improves clinical outcome in the intermediate follow up, but its long-term effect remains to be further evaluated.     

Long term results of endovascular treatment in renal arterial stenosis from Takayasu arteritis: Angioplasty versus stent placement

Purpose

To retrospectively evaluate and compare the long term patency and antihypertensive effect of angioplasty and stent insertion in renal artery stenosis caused by Takayasu arteritis, with CT angiography and clinical follow-up.

Materials and methods

We retrospectively analyzed and compared effects on hypertension and patency of renal artery in 16 patients (age ranging from 16 to 58 years, mean: 32.1 years) with renovascular hypertension caused by Takayasu arteritis who underwent endovascular treatment including angioplasty (n = 13) and stent placement (n = 9) for 22 stenotic renal arteries.

Results

Technical success was 95% (21/22) without major complications. In the last follow-up CT angiogram (mean 85 ± 41 months), restenosis was 8% (1/12) in angioplasty and 66% (6/9) in stent. Patency rates of angioplasty were 100%, 91.7%, 91.7% and primary unassisted and primary assisted patency rates of stent placement were 55.6%, 33.3%, 33.3% and 88.9%, 66.7%, 55.6% at 1-, 3- and 5-years, respectively. In clinical follow-up (mean 120 ± 37.8 months, range 48–183 months), beneficial effects on hypertension were obtained in 87% of patients (13/15) and there was no significant difference between the patients who were treated by only angioplasty and the patients who received stent placement in at least one renal artery, regardless of whether or not angioplasty had been performed in the other renal artery.

Conclusion

Compared with stent placement, angioplasty demonstrated better long term patency and similar clinical benefit on renovascular hypertension in renal artery stenosis of Takayasu arteritis. We suggest that stent placement should be reserved for obvious angioplasty failure.     

Endovascular treatment of tandem occlusions of the anterior cerebral circulation with solitaire FR thrombectomy system. Initial experience

Purpose

The optimal treatment in the acute phase of cervical internal carotid occlusion associated with intracranial obstruction is a matter of debate. In this study, we report our experience using the Solitaire FR revascularization device and synchronous intravenous fibrinolysis. The distal occlusion was treated with Solitaire FR before the proximal one in all cases, a technique not reported so far in the literature.

Methods

We examined all cases of tandem occlusion treated in our institution between November 2009 and November 2010. The proximal occlusion was treated using manual thromboaspiration in order to achieve intracranial recanalization as rapid as possible. When necessary, stenting was performed after the reconstitution of the intracranial vessel. Morphological and clinical results were recorded in the immediate post-operative phase and at the three-month follow-up. Clinical success was defined as a mRS at 3 months ≤2.

Results

Four male and six female patients were treated (mean age 66 years). The cervical carotid was recanalized in all cases and the intracranial vessel (TICI ≥ 2b) in eight. Adverse events were recorded in four patients of which three were asymptomatic. These included two cases of subarachnoid hemorrhage, one case of traumatic dissection, and one case of fatal intra-cerebral hemorrhage seven days following the procedure. At the three-month follow-up a mRS ≤ 2 was observed in four patients.

Conclusions

The described approach for the treatment of tandem occlusions is promising with regard to both morphological and clinical assessments and thus may be considered a valid tool in acute stroke.     

Angioplasty or Stenting of Extra- and Intracranial Vertebral Artery Stenoses

Purpose: To determine the feasibility and safety of angioplasty or angioplasty and stenting of extra- and intracranial vertebral artery (VA) stenosis. Methods: In 16 consecutive patients (9 men, 7 women; mean age 61 years, range 49–74 years) 16 stenotic VAs were treated with angioplasty or angioplasty and stenting. Eleven stenoses were localized in V1 segment, 1 stenosis in V2 segment and 4 stenoses in V4 segment of VA. Fourteen VA stenoses were symptomatic, 2 asymptomatic. The etiology of the stenoses was atherosclerotic in all cases. Results: Angioplasty was performed in 8 of 11 V1 and 2 of 4 V4 segments of the VA. In 3 of 11 V1 segments and 2 of 4 V4 segments of the VA we combined angioplasty with stenting. The procedures were successfully performed in 14 of 16 VAs (87%). Complications were asymptomatic vessel dissection resulting in vessel occlusion in 1 of 11 V1 segments and asymptomatic vessel dissection in 2 of 4 V4 segments of the VA. One patient died in the 24-hr period after the procedure because of subarachnoid hemorrhage as a complication following vessel perforation of the treated V4 segment. Conclusion: Angioplasty or angioplasty and stenting of extracranial VA stenoses can be performed with a high technical success rate and a low complication rate. In intracranial VA stenosis the procedure is technically feasible but complications can be life-threatening. The durability and procedural complication rates of primary stenting without using predilation in extra- and intracranial VA stenosis should be defined in the future.     

Prevalence of venous sinus stenosis in Pseudotumor cerebri (PTC) using digital subtraction angiography (DSA)

Objectives

To study the prevalence of intracranial venous stenosis in Pseudotumor cerebri patients.

Patients and methods

Thirty patients were diagnosed having PTC according to Dandy criteria. All underwent general and neurological assessment. Radiological assessment included CT scan brain ±MRI brain without contrast, MRV. All underwent digital subtraction angiography (DSA) (venous phase) to confirm the validity of filling gaps seen at the level of MRV.

Results

MRV brain showed that 24 patients (80%) showed filling gaps. Digital subtraction cerebral angiography (venous phase) showed 9 patients (30%) had stenosis in their dural sinuses. MRV showed to be a good screening tool since it had 100% sensitivity and negative predictive value. However, since it has a moderate specificity (62%) with a positive predictive value (PPV) of only 35%, then lesions detected should be confirmed with digital subtraction cerebral angiography (venous phase) particularly those involving the transverse and sigmoid sinus.

Conclusion

Studying the intracranial venous system in patients with PTC is an important step in understanding the pathophysiology of the disease. Detection of venous sinus stenosis opens the way to a novel therapeutic option for refractory patients like venous sinus stenting.     

Stent-assisted angioplasty of symptomatic intracranial vertebrobasilar artery stenosis: feasibility and follow-up results

BACKGROUND AND PURPOSE: The natural history of symptomatic, untreated posterior circulation stenosis is dismal, with many patients experiencing significant morbidity or mortality. The purpose of this study was to evaluate the feasibility and results of stent-assisted angioplasty of symptomatic intracranial vertebrobasilar artery stenosis.METHODS: We reviewed the imaging findings and medical records of 17 consecutive patients who were treated with stent-assisted angioplasty for medically refractory vertebrobasilar artery stenosis. The location of the lesion, degree of stenosis, procedure-related complications, and clinical and short- and long-term angiographic results were assessed.RESULTS: The population included 17 cases (10 men, seven women; age range, 51–74 years; mean, 64 years). The locations of the lesions were intracranial vertebral artery (n = 13) and basilar artery (n = 6). The mean degree of stenosis decreased from 76.1 ± 14.6% before stent-assisted angioplasty to 1.3 ± 2.8% (P < .05) after the procedure. Acute in-stent thrombosis developed in one case (6%, Mori type B lesion), which was successfully treated with intraarterial abciximab infusion and angioplasty. Another patient (6%, Mori type C lesion) developed immediate postprocedural transient diplopia and ataxia, which gradually resolved. No other patient showed symptoms related to the vertebrobasilar artery lesion at follow-up. No significant restenosis was observed at short-term (five patients; follow-up range, 0.5–6 months; mean, 4.3 months) or long-term (six patients; follow-up range, 12–41 months; mean, 21 months) angiographic follow-up.CONCLUSION: Stent-assisted angioplasty is a feasible treatment method for vertebrobasilar artery stenosis. The patency of the stent-assisted angioplasty seems to be preserved in the long-term, with good clinical outcome.

The natural history of untreated posterior circulation stenosis is dismal, with many patients experiencing significant morbidity or mortality (1–3). Retrospective data suggest that the annual stroke rates for patients with symptomatic intracranial vertebral or basilar artery stenosis are 7.8% and 10.7%, respectively, despite anticoagulation or antiplatelet therapy (3).Recently, percutaneous transluminal angioplasty was proposed as a promising alternative treatment for patients with intracranial atherosclerotic stenosis symptoms despite medical therapy. However, percutaneous transluminal angioplasty has had the problems of dissection, elastic recoil, and thrombosis (4, 5). In a series of 42 cases of angioplasty for intracranial stenosis by Mori et al (4), the 1-year angiographic restenosis rate in type A (short, ≤5 mm in length, concentric or moderately eccentric lesions not totally occlusive), type B (tubular, 5–10 mm in length, extremely eccentric or totally occluded lesions, <3 months old), and type C (diffuse, >10 mm in length, extremely angulated [>90°] lesions with excessive tortuosity of the proximal segment, or totally occluded lesions, and ≥3 months old) lesions were 0%, 33%, and 100%, respectively, with cumulative risk of fatal or nonfatal ipsilateral ischemic stroke in 8%, 12%, 56%, respectively, at 1 and 2 years.Stent-assisted angioplasty has been limited mainly by the apprehension concerning the technical feasibility, periprocedural complications, and short- and long-term outcomes (6). Major problems still exist; nonetheless, recent technical advances in instruments used for angioplasty and stent placement have allowed easier trackability through the small and tortuous intracranial vessels. Also, experience from the earlier works of intracranial angioplasty and stent placement has allowed a relatively safe procedure with fewer periprocedural complications (7–14).We reviewed our experience with stent-assisted angioplasty for medically refractory intracranial vertebral and basilar artery stenoses, including the intra- and periprocedural complications and long-term angiographic and clinical outcomes.     

Factors influencing technical success and outcome of percutaneous balloon angioplasty in de novo native hemodialysis arteriovenous fistulas

Objective

To determine predictors of technical success, dysfunction recurrence and patency after percutaneous transluminal angioplasty (PTA) of de novo dysfunctional hemodialysis arteriovenous fistulas (AVFs).

Methods

Retrospective analysis of first time PTA of 167 AVF in 162 patients (100 men, 66 ± 13 years). Anatomical (location, length, grade and number of stenoses) and clinical variables (sex, age, prior AVF, diabetes mellitus and AVF age, side and location) were reviewed.

Results

217 stenoses or segmental occlusions were treated. Technical success rate (84.4%) was higher in radiocephalic AVF compared to brachial artery–median vein AVF (p = 0.030) and was negatively correlated with initial stenosis (p = 0.049). Dysfunction recurrence was seen in 52.7% and correlated negatively with technical success (p = 0.013) and AVF age (p = 0.008). Early dysfunction (within 6 months) was negatively correlated with AVF age (p = 0.016) and positively with diabetes (p = 0.003). Higher AVF age resulted in higher primary (p = 0.005) and secondary patency rates (p = 0.037–0.005).

Conclusions

Technical success of PTA in hemodialysis AVF is affected by AVF type and initial stenosis and has significant effect on dysfunction recurrence, but not on AVF longevity. Younger AVF has increased risk for (early) recurrent dysfunction and lower patency rates. Patients with diabetes mellitus have higher risk for early dysfunction.     

Endovascular therapy of symptomatic intracranial stenosis in patients with impaired regional cerebral blood flow or failure of medical therapy

BACKGROUND AND PURPOSE:Symptomatic intracranial stenoses have a high risk for a recurrent stroke if treated medically. Although angioplasty and stent placement are proposed treatment options, data on longer-term outcome are limited.Materials and METHODS:We analyzed all endovascular procedures on symptomatic intracranial stenosis at our institution from January 1998 to December 2005. We retrospectively assigned patients to group A (symptoms despite antithrombotic therapy) or group B (impaired regional cerebral blood flow [rCBF]). Primary outcome events were periprocedural major complications or recurrent ischemic strokes in the territory of the treated artery. We used the Kaplan-Meier method to calculate survival probabilities.RESULTS:The procedural technical success rate was 92% (35/38) with periprocedural major complications in 4 cases (10.5%; group A [8.3%, 2/24], group B [14.3%, 2/14]). Median (range) follow-up for the 33 patients with technically successful procedures was 21 (0–72) months. Recurrent ischemic strokes occurred in 15% (3/20) of patients in group A and 0% (0/13) of patients in group B. Overall, there were 21% (7/33) primary outcome events (group A [25%, 5/20], group B [15%, 2/13]). There was a nonsignificant trend for better longer-term survival free of a major complication or recurrent stroke in patients with impaired rCBF compared with patients who were refractory to medical therapy treatment (Kaplan-Meier estimate 0.85 [SE 0.10] vs 0.72 [SE 0.11] at 2 years, respectively).CONCLUSION:Interventional treatment of symptomatic intracranial stenosis carries significant risk for complications and recurrent stroke in high-risk patients. The observation that patients with impaired rCBF may have greater longer-term benefit than medically refractory deserves further study.

Atherosclerotic stenosis of the major intracranial arteries accounts for 8%–10% of all ischemic strokes^{1, 2} and, after a symptomatic event, the annual risk of recurrence is high (estimates, 8%–11%).^3–5 However, the optimum strategy for secondary prevention in this situation remains uncertain. In particular, the Warfarin-Aspirin Symptomatic Intracranial Disease (WASID) study failed to show a benefit of warfarin compared with aspirin in the prevention of recurrent ischemic events.⁴Interventional procedures such as percutaneous transluminal angioplasty (PTA) and stent placement have been proposed as potentially more effective methods of secondary prevention. Two groups of patients are frequently considered as potential target groups for endovascular therapy. First, patients who have recurrent ischemic events despite standard medical therapy and second (and more recently), patients with clinically apparent impaired regional cerebral blood flow (rCBF) secondary to the stenoses.^6–9 Both groups are considered to be at especially high risk for stroke, which justifies the use of a potentially risky procedure. However, the acute risks and long-term outcome of such endovascular therapies in both subgroups are still poorly described.The purpose of this study, therefore, was to report our experience with angioplasty and stent placement for symptomatic intracranial atherosclerotic stenoses in patients who have either failed medical therapy or who have impaired rCBF secondary to intracranial stenoses.     

血管内支架成形术治疗颅内动脉狭窄28例

目的探讨血管内支架成形术治疗颅内动脉狭窄的临床效果和安全性。方法 2006年7月—2010年12月,采用经皮血管内支架成形术治疗颅内狭窄28例。结果治疗狭窄颅内动脉28支,其中置入冠脉球扩式支架16枚,Wingspan支架6枚,apollo支架6枚,支架不能到位,放弃手术1例。27支动脉狭窄程度均明显改善,狭窄程度由原来的(89.36±5.63)%下降至(4.23±1.57)%,无死亡病倒,术后27例患者症状均明显改善,1例基底动脉重度狭窄患者术后出现一侧肢体麻木的并发症,1例术后出现脑栓塞表现,3 d后恢复正常,其他26例患者无并发症,随访2～12个月,无短暂性脑缺血发作(TIA)发作,随访患者经颅多普勒超声(TCD)结果显示,原狭窄血管近端、远端血流速度和支架置入后24 h的TCD结果无明显差别。结论血管内支架成形术是治疗症状性颅内动脉狭窄的安全、有效的方法,临床效果好,并发症少。适应证的正确选择、术中熟练的导管导丝技术和围术期的专业处理是手术成功的关键,但其远期疗效还需要长期随访。     

Catheter-Directed Thrombolysis with a Continuous Infusion of Low-Dose Urokinase for Non-Acute Deep Venous Thrombosis of the Lower Extremity

Objective

We wanted to evaluate the feasibility of catheter-directed thrombolysis with a continuous infusion of low-dose urokinase for treating non-acute (less than 14 days) deep venous thrombosis of the lower extremity.

Materials and Methods

The clinical data of 110 patients who were treated by catheter-directed thrombolysis with a continuous infusion of low-dose urokinase for lower extremity deep venous thrombosis was analysed. Adjunctive angioplasty or/and stenting was performed for the residual stenosis. Venous recanalization was graded by pre- and post-treatment venography. Follow-up was performed by clinical evaluation and Doppler ultrasound.

Results

A total of 112 limbs with deep venous thrombosis with a mean symptom duration of 22.7 days (range: 15-38 days) were treated with a urokinase infusion (mean: 3.5 million IU) for a mean of 196 hours. After thrombolysis, stent placement was performed in 25 iliac vein lesions and percutaneous angioplasty (PTA) alone was done in five iliac veins. Clinically significant recanalization was achieved in 81% (90 of 112) of the treated limbs; complete recanalization was achieved in 28% (31 of 112) and partial recanalization was achieved in 53% (59 of 112). Minor bleeding occurred in 14 (13%) patients, but none of the patients suffered from major bleeding or symptomatic pulmonary embolism. During follow-up (mean: 15.2 months, range: 3-24 months), the veins were patent in 74 (67%) limbs. Thirty seven limbs (32%) showed progression of the stenosis with luminal narrowing more than 50%, including three with rethrombosis, while one revealed an asymptomatic iliac vein occlusion; 25 limbs (22%) developed mild post-thrombotic syndrome, and none had severe post-thrombotic syndrome. Valvular reflux occurred in 24 (21%) limbs.

Conclusion

Catheter-directed thrombolysis with a continuous infusion of low-dose urokinase combined with adjunctive iliac vein stenting is safe and effective for removal of the clot burden and for restoration of the venous flow in patients with non-acute lower extremity deep venous thrombosis.     

Changes in cerebral hemodynamics after carotid stenting of symptomatic carotid artery

Purpose

To evaluate changes in cerebral hemodynamics after carotid stenting of symptomatic carotid artery in the patients who underwent ischemic stroke caused by carotid artery stenosis.

Methods

Twenty patients with unilateral symptomatic carotid artery stenosis received brain computer tomography perfusion (CTP) scan a week before and a week after carotid artery stenting. Three absolute values including mean transit time (MTT), cerebral blood volume (CBV), and cerebral blood flow (CBF) were acquired and analyzed by use of the post-processing software. Six vascular territories such as ACA territory, MCA territory, PCA territory, basal ganglia, watershed between ACA and MCA territory (frontal watershed), watershed between MCA and PCA territory (posterior watershed) were chosen for comparison. Relative parameter values were defined as rCBF (relative CBF), rCBV (relative CBV), rMTT (relative MTT) through comparing absolute values in symptomatic hemispheres to absolute values in asymptomatic hemispheres. The relative perfusion parameter values before treatment were compared with post-treatment values. These analyses were performed by using the paired t test.

Results

The mean rMTT decreased significantly in ACA territory, MCA territory and two watershed after treatment, while the mean rCBF increased significantly in those areas after treatment. But the mean rCBV had no significant changes in all six vascular territories. In PCA territory, all the parameters had no significant changes.

Conclusion

Carotid artery stenting yields satisfactory cerebral perfusion in ACA territory, MCA territory, basal ganglia and two watersheds.     

Endovascular treatment of idiopathic intracranial hypertension: retrospective analysis of immediate and long-term results in 51 patients

Purpose

Idiopathic intracranial hypertension (IIH) is a disorder of increased intracranial pressure in the absence of any known causative factor. Sinus stenosis is common in these patients. Stenting of stenotic dural sinuses has gained popularity as a treatment option, since these stenoses may contribute to an obstruction of the venous return, and, thereby may contribute to IIH via an increase in venous sinus pressure. We evaluated the safety and efficacy of endovascular treatment in IIH with venous sinus stenosis.

Methods

Fifty-one patients with IIH underwent stenting. Median age was 40 years. Clinical manifestation was headache in 74.5% of the patients and visual obscurations in 78.5%. Papilledema was present in 50/51 patients (98%), and lumbar puncture documented elevated CSF opening pressure in all but one patient (98%). Sinus stenoses were observed in all patients.

Results

Endovascular treatment was successfully performed in all patients. There were no major complications encountered (i.e., live threatening or causing a deterioration of a patient’s condition equivalent to mRS 3–6). Improvement or resolution of papilledema was observed in 88% of the patients, and 84% reported improvement or resolution of the headache. Follow-up angiographies were performed in 48 patients at a median interval of 49 months and demonstrated in stent-stenosis or a de novo stenosis in 12 patients, eight of them needed re-treatment.

Conclusion

Venous sinus stenting is a safe and effective alternative to other invasive treatments (e.g., optic nerve sheath fenestration, CSF diversion) in patients with IIH. The majority of patients have a persistent clinical benefit.

     

Value of endovascular stent placement for symptomatic spontaneous isolated superior mesenteric artery dissection

Objective

To evaluate the feasibility and efficacy of endovascular stent placement for the treatment of symptomatic spontaneous isolated superior mesenteric artery dissection.

Materials and methods

This retrospective study was undertaken in 12 consecutive patients who suffered from symptomatic spontaneous isolated superior mesenteric artery dissection. Seven patients with severe clinical symptoms underwent endovascular stent placement as a primary treatment and the other 5 patients received conservative treatment. The technical results, complications and clinical outcomes were analyzed. Follow-up was performed with computed tomographic angiography.

Results

Primary endovascular stent placement was successfully performed in 7 patients with severe clinical symptoms. Successful conservative treatment was achieved in 3 patients. Endovascular stent placement was additionally performed in 2 patients with unsuccessful conservative treatment. A stent was misplaced in the false lumen in one of those two patients due to a severely stenotic true lumen. The fasting time and length of stay were significantly shorter in patients with successful endovascular therapy (median: 3 days and 5.5 days) than in those conducted conservatively (median: 9 days and 14 days) (p < 0.05). During the follow-up period (median, 21 months; range, 10–36 months), 1 patient with endovascular stent placement had recurrent abdominal pain because of the wall adherent thrombus in the proximal segment of the superior mesenteric artery during the first follow-up month. No thrombosis or stenosis was found in the lumina of the stents.

Conclusion

Endovascular stent placement is a safe and feasible therapeutic approach for symptomatic spontaneous isolated superior mesenteric artery dissection with immediate success and satisfactory outcomes.     

Treatment of intracranial stenoses using the Neuroform stent system: initial experience in five cases

Introduction We assessed the technical feasibility of balloon-assisted angioplasty with consecutive stenting using a flexible, self-expanding neurovascular stent for the treatment of intracranial arteriosclerotic vascular stenoses. Methods Five consecutive patients with symptomatic drug-resistant stenoses of the intracranial internal carotid artery (ICA) or the main stem of the middle cerebral artery (MCA) were treated by balloon-assisted angioplasty with consecutive stenting using the Neuroform stent system.Results Balloon dilatation of the stenoses and consecutive stent placement with complete coverage of the stenoses was feasible in all patients. One patient suffered acute thrombosis distally to the stented vessel segment which was successfully treated by fibrinolysis, and one patient suffered acute subarachnoid and parenchymal hemorrhage probably due to vessel perforation. In the other three patients, no complications occurred during or immediately after angioplasty. All patients were free of further ischemic events up to the 6-month follow-up.Conclusion Our findings demonstrate that the Neuroform stent system can used successfully for the treatment of intracranial stenoses of the ICA and the main stem of the MCA. Although immediate angiographic results are promising, long-term angiographic and clinical follow-up is essential to demonstrate long-term outcome.     

Peri-stent aneurysm formation following a stent implant for stenotic intracranial vertebral artery dissection: a technical report of two cases successfully treated with coil embolization

Introduction

Although stenting for stenotic vertebral artery dissection (VAD) improves compromised blood flow, subsequent peri-stent aneurysm (PSA) formation is not well-known. We report two cases with PSA successfully treated with coil embolization.

Methods

Three patients with stenotic intracranial VAD underwent endovascular angioplasty at our institution because they had acute infarction in posterior circulation territory and clinical evidence of hemodynamic insufficiency. In two of three patients balloon angioplasty at first session failed to relieve the stenosis, and a coronary stent was implanted. Angiography immediately after stenting showed no abnormality in case 1 and minimal slit-like projection at proximal portion of the stent in case 2.

Results

Angiography obtained 16 months after the stenting revealed PSA in case 1. In case 2, angiography performed 3 months later showed that the projection at proximal portion enlarged and formed an aneurysm outside the stent. Because follow-up angiographies showed growth of the aneurysm in both cases, endovascular aneurysmal embolization was performed. We advanced a microcatheter into the aneurysm through the strut of existing stent and delivered detachable coils into the aneurysm lumen successfully in both cases. The post-procedural course was uneventful, and complete obliteration of aneurysm was confirmed on angiography in both cases.

Conclusion

Stenting for stenotic intracranial VAD may result in delayed PSA; therefore, follow-up angiographies would be necessary after stenting for stenotic intracranial arterial dissection. Coil embolization through the stent strut would be a solution for enlarging PSA.     

Tiny intracranial aneurysms: endovascular treatment by coil embolisation or sole stent deployment

Purpose

Tiny intracranial aneurysms pose a significant therapeutic challenge for interventional neuroradiologists. The authors report their preliminary results of endovascular treatment of these aneurysms.

Methods

Between January 2002 and December 2009, 52 tiny intracranial aneurysms (defined as ≤3 mm in maximum diameter) in 46 patients (22 men; mean age, 57.9 years) were treated by endosaccular coil embolisation or sole stent deployment in the parent artery. Of 52 aneurysms, 29 had ruptured and 23 remained unruptured. The initial angiographic results, procedural complications, and clinical outcomes were assessed at discharge. Imaging follow-up was performed with cerebral angiography.

Results

One aneurysm coiling procedure failed because of unsuccessful micro-catheterization. Forty-three aneurysms were successfully coil embolized, of which complete occlusion was obtained in 14, subtotal occlusion in 18 and incomplete occlusion in 11. The other 8 aneurysms were treated by sole stent deployment in the parent artery. Procedural complications (2 intraprocedural ruptures and 3 thromboembolic events) occurred in 5 (9.6%) of 52 aneurysms, resulting in permanent morbidity in only 1 (2.2%, 1/46) patient. No rebleeding occurred during clinical follow-up (mean duration, 46.7 months). Of the 16 coiled aneurysms that receiving repetitive angiography, 6 initially completely and 3 subtotally occluded aneurysms remained unchanged, 4 initially subtotally and 3 incompletely occluded aneurysms progressed to total occlusion. Five sole stent deployed aneurysms received angiographic follow-up (mean duration, 10.0 months), of which 3 remained unchanged, 1 became smaller and 1 progressed to total occlusion.

Conclusion

Endovascular treatment of tiny intracranial aneurysms is technical feasible and relatively safe. Coil embolisation seems to be effective in preventing early recanalisation, whereas sole stenting technique needs further investigation to determine its effectiveness.