Surgical strategies for treatment of giant or large intracranial aneurysms: our experience with 139 cases.

Giant or large intracranial aneurysms are the vascular neurosurgeon's greatest challenge. At our department, we have treated one hundred and thirty nine patients with giant or large intracranial aneurysms between 1975 and 2001. These included 37 partially thrombosed giant aneurysms. 75 aneurysms were giant (> 2.5 cm) and 64 were large aneurysms (2-2.5 cm). Three-dimensional computed tomography angiograms were performed in patients besides MRI angiography and digital subtraction angiography. These were found to be very valuable in the preoperative assessment of surgical anatomy of the aneurysm with respect to the branch arteries and perforators origin besides knowing the relations to the skull base. With our experience in surgical treatment of these 139 cases, we find that the basic technique is trapping and evacuation and not just clipping of the aneurysm neck but also reconstruction of the artery bearing the aneurysm, especially with wide-necked aneurysms. Use of multiple clipping, tandem clipping or dome clipping as per the intraoperative situation, is very helpful in dealing with giant aneurysms as also is the use of different types of clips like fenestrated clip with straight clip (combination clipping), booster clip, dome clips etc. While selecting surgical strategy for partially thrombosed giant aneurysm, securing the neck is most important. If the neck is too narrow to reconstruct, aneurysmectomy with anastomosis is one of the surgical strategies. An extracranial intracranial bypass should be considered in cases where clipping or parent artery ligation is expected to be associated with compromise of cerebral circulation.     

Pipeline flow diversion with adjunctive coil embolization for internal carotid artery aneurysms following an intradural component: results in 46 consecutive aneurysms from a Japanese single-center experience

In the treatment of an intracranial aneurysm with the flow diverter, the combined use of coil embolization can help promote subsequent progressive thrombosis within the aneurysm sac and reduce the risk of delayed aneurysm rupture. This study retrospectively reviewed outcomes of patients who had undergone the Pipeline Embolization Device (PED) with adjunctive coil embolization (PED/coil) at a single center to determine its safety and efficiency. Patients with internal carotid artery aneurysms following an intradural component were selected for PED/coil between 2015 and 2020. All patients were premedicated with dual antiplatelet therapy of aspirin plus clopidogrel or prasugrel. A minimal number of PEDs were deployed, with coils inserted using a stent-jail technique, avoiding dense packing. A total of 46 aneurysms (43 patients; median dome size, 11.6 mm; median neck width, 6.3 mm) were treated with PED/coil. The median volume embolization ratio was 14.8%. The degree of angiographic filling at the 6-month and latest angiography showed complete occlusion in 60.5% (26/43) and 70.5% (31/44), respectively. Small (<?10 mm) aneurysms achieved a higher complete occlusion rate in the early period; a lower cumulative incidence of aneurysm occlusion was observed in large and giant (≥?10 mm) aneurysms (P?=?.024). The median clinical follow-up was 22 months, and no aneurysm ruptures occurred. Favorable clinical outcomes were achieved, with permanent neurological morbidity of 4.7% and no mortality. PED/coil demonstrated a high angiographic occlusion rate at an early stage. Loosely packed coils are sufficient to obliterate aneurysms effectively.

     

Surgically treated aneurysms previously coiled: lessons learned

OBJECTIVE: Intravascular coil embolization of cerebral aneurysms has proved to be a safe and effective treatment in certain patient groups; however, this treatment is relatively new, and the long-term outcomes are unknown. One of the known complications is refilling of the aneurysm dome, which is seen in follow-up studies. This patient population poses unique technical difficulties for the neurosurgeon. We present a series of 18 patients who underwent surgery for residual aneurysms after coil remobilization. METHODS: During a 5-year period, we performed surgery in 18 patients who had previously undergone coil embolization for their aneurysms. Of these aneurysms, four were in the anterior communicating artery, five were in the posterior communicating artery, three were in the internal carotid artery, three were in the posteroinferior cerebellar artery, and three were in the middle cerebral artery. One patient presented with rupture, one presented with acute IIIrd cranial nerve palsy, and the rest of the aneurysms were found on routine follow-up angiograms. Fifteen aneurysms were clipped, and in three patients, they were wrapped because the clip could not be placed adequately. RESULTS: There were no major complications in any of the patients, and all had uneventful recoveries. The presence of coils in the aneurysm dome and/or neck made clipping and exposure of the aneurysm neck difficult, resulting in incomplete neck obliteration in three patients. CONCLUSION: Operative clipping after previous coil embolization in aneurysms poses a unique problem for neurosurgeons. With the increasing use of coil embolization, this patient population will undoubtedly increase. The neurosurgeon should be aware of the difficulties and pitfalls encountered in these patients.     

Complementary management of partially occluded aneurysms by using surgical or endovascular therapy

OBJECT: The authors present a series of patients in whom partially occluded aneurysms were retreated using complementary surgical or endovascular therapy. METHODS: During a period of 18 months, 301 patients with intracranial aneurysms were treated using either clip application (171 patients) or endovascular embolization with Guglielmi Detachable Coils ([GDCs] 130 patients). Routine posttreatment angiography studies revealed residual aneurysms in 21 of these patients, nine of whom were retreated using an endovascular or surgical method, with a mean treatment latency of 1.2 months. Four patients underwent primary surgical clip application, whereas five patients experienced GDC packing first. Among patients in the surgical group, the residual aneurysm neck was small and total elimination of the aneurysm was achieved by packing in GDCs. In patients in the endovascular group the authors incompletely packed the aneurysm because of its wide neck or fusiform component in two patients, perforation of a very small aneurysm in one patient, and coil dislocation in another patient. Typical coil compaction occurred in one case. Complete clip application was achieved in all patients. There was no complication in any patient due to the second treatment modality. Final outcome was excellent or good in six and fair in three. CONCLUSIONS: Following clip application or endovascular embolization of intracranial aneurysms, the use of complementary surgical or endovascular management is successful and associated with low morbidity.     

Endovascular treatment for basilar tip aneurysms

The aim of this study was to analyze the effect of endovascular treatment of basilar (BA) tip aneurysms. The authors performed a retrospective analysis of 79 aneurysms of the BA tip that had been treated using endovascular coil embolization for the last 11 years. Fifty-six patients were women, and 23 were men. The average age of the patients was 63.7 years (range, 35-83 year). The average maximum diameter of the aneurysms was 8.0 mm (range, 2-30 mm). Forty-seven patients (60%) presented with acute subarachnoid hemorrhage (SAH), 1 patient (1%) had an unruptured aneurysm with mass effect, and 31 patients (39%) had incidental aneurysms. Immediate anatomic outcomes demonstrated complete occlusion (CO) in 53 aneurysms (67%), residual neck (RN) in 22 aneurysms (28%), and residual aneurysm (RA) in 4 aneurysms (5%). One patient died from rebleeding 6 hours after the embolization. Another patient suffered from rebleeding 6 years after the initial embolization, and was successfully treated with re-embolization. Four patients suffered from asymptomatic P1 occlusion. No symptomatic complication was observed in the unruptured group. Retreatment was performed in 5 patients, including 4 broad-neck large ruptured aneurysms and 1 giant thrombosed aneurysm. Angiographic and clinical results have been improving in recent cases in this study. Technical advances such as highly compliant balloon remodeling microcatheter and 3D-reconstructed digital angiography contributed to this improvement. Our results indicate that endovascular treatment of BA tip aneurysm is safe and effective. The long-term stability after coil embolization is still a matter of concern. Further improvement is expected.     

WingSpan Stent System in the endovascular treatment of intracranial aneurysms: clinical experience with midterm follow-up results

OBJECT: The WingSpan stent is a new self-expandable neurovascular stent designed for endovascular treatment of intracranial atheromatous lesions. The authors report their experience with the use of this stent for the endovascular treatment of intracranial aneurysms. METHODS: Thirty-seven patients with 40 wide-necked intracranial aneurysms were treated using the WingSpan stent. Twenty-two aneurysms (55%) were small and 18 (45%) were large or giant. In all but 4 aneurysms, embolization was completed by packing the aneurysm sac with platinum coils. In 4 dissecting aneurysms that were fusiform or too small and wide necked to be catheterized, the stent was used alone. In these cases, the stent bridged the aneurysm neck to allow for flow redirection and the potential stent-induced endothelization effect. RESULTS: Follow-up angiograms obtained in 3 of 4 aneurysms, treated with only stent placement, demonstrated aneurysmal thrombosis and parent artery remodeling in 2 patients and moderate decrease in size in 1. Follow-up angiography obtained at 6 months to 1 year in 31 aneurysms after stent-supported coil embolization demonstrated complete occlusion in 23 aneurysms (74.2%) with a progressive thrombosis rate of 66.7% (10 of 15 aneurysms), and a recanalization rate of 16.1%. CONCLUSIONS: In treating wide-necked intracranial aneurysms, the WingSpan Stent System is very flexible, secure, and effective. Its delivery system is very easy and exact in that it exerts higher outward radial force, thus providing an excellent conformability and a strong scaffold to hold the coils in place. It may offer an effective treatment when used alone in some fusiform or very wide-necked, small dissecting aneurysms in which other surgical or endovascular treatment strategies are not deemed feasible.     

Guglielmi detachable coil embolization of cerebral aneurysms: 11 years' experience

OBJECT: The authors report on their 11 years' experience with embolization of cerebral aneurysms using Guglielmi Detachable Coil (GDC) technology and on the attendant anatomical and clinical outcomes. METHODS: Since December 1990, 818 patients harboring 916 aneurysms were treated with GDC embolization at University of California at Los Angeles Medical Center. For comparative purposes, the patients were divided into two groups: Group A included their initial 5 years' experience with 230 patients harboring 251 aneurysms and Group B included the later 6 years' experience with 588 patients harboring 665 aneurysms. Angiographically demonstrated complete occlusion was achieved in 55% of aneurysms and a neck remnant was displayed in 35.4% of lesions. Incomplete embolization was performed in 3.5% of aneurysms, and in 5% occlusion was attempted unsuccessfully. A comparison between the two groups revealed a higher complete embolization rate in patients in Group B compared with that in Group A patients (56.8 and 50.2%, respectively). The overall morbidity/mortality rate was 9.4%. Angiographic follow ups were obtained in 53.4% of cases of aneurysms, and recanalization was exhibited in 26.1% of aneurysms in Group A and 17.2% of those in Group B. The overall recanalization rate was 20.9%. Note that recanalization was related to the size of the dome and neck of the aneurysm. Overall incidence of delayed aneurysm rupture was 1.6%, a rate that improved in the past 5 years to 0.5%. Ten of 12 delayed ruptures occurred in large or giant aneurysms. CONCLUSIONS: The clinical and postembolization outcomes in patients treated with the GDC system have improved in the past 5 years. Aneurysm recanalization, however, is still a major limitation of current GDC therapy. Follow-up angiography is mandatory after GDC embolization of cerebral aneurysms. Further technical and device improvements are mandatory to overcome current GDC limitations.     

颅内动脉瘤囊内栓塞结果影像学判断标准的探讨

目的 探讨颅内动脉瘤囊内栓塞结果的影像学判断标准。方法 ６名专科医师根据动脉瘤栓塞后血管造影不显影为１００％、瘤颈少许残留为９５％、瘤颈残留为９０％、瘤颈残留并有少许瘤体残留为８０％和少部分瘤体残留为〈８０％的栓塞判断标准,对１９９５年３月至１９９９年７月用机械可脱式弹簧圈和（或）电解可脱式弹簧圈囊内栓塞的１２０例（１２１个）动脉瘤的血管造影片进行评价,并分析该标准的合理性、可行性和局限性。结果     

Giant celiac artery aneurysm: Treatment by transcatheter coil embolization

Celiac artery aneurysms (CAA) are one of the rarest forms of visceral artery aneurysms. Most patients are a symptomatic at the time of diagnosis and aneurysms are detected incidentally during diagnostic imaging for other diseases. We present the case of a 42-year-old man who had an asymptomatic giant CAA detected incidentally by an abdominal ultrasound investigating an abdominal pain. A contrast enhanced computed tomography angiogram (CTA) revealed a large CAA measuring 7.1 cm × 4.3 cm with extensive collaterals from the superior mesenteric artery (SMA). The aneurysm sac was mostly filled with thrombus with the celiac artery branches occluded. Pre-procedural angiography and transcatheter embolization procedures were performed at the same session. Endovascular exclusion was performed by transcatheter coil embolization and packing of the aneurysm sack. Technical success was achieved by the absence of flow in the aneurysm, and preservation of the native circulation on angiograms obtained just after the transcatheter coil embolization procedure. One week postembolization, a CTA confirmed thrombosis of the aneurysm. The patient returned for a follow-up CTA 3, 6, 12 and 48 months after embolization. The aneurysm was thrombosed and the patient remained a symptomatic. The surgical mode of treatment of CAA is increasingly being replaced by endovascular embolization because of the lower morbidity and mortality and high success rate. The accepted endovascular approach is by coil embolization of the aneurysmal lumen, the proximal and distal aneurysmal neck, or both.     

前循环动脉瘤的介入治疗（附40例分析）

目的 探讨前循环动脉瘤介入栓塞的临床疗效及并发症的处理.方法 对40例前循环动脉瘤患者采用介入栓塞治疗（42枚）,其中颈内动脉动脉瘤2例（2枚）,大脑中动脉动脉瘤18例（20枚）,前交通动脉瘤15例（15枚）,大脑中-后交通动脉动脉瘤5例（5枚）.结果 介入栓塞动脉瘤40例（42个）,栓塞率达100％的36个,95％的5个,90％的1个.随访共37例,3例失访.所有患者均复查头颅CT,原则上要求均复查DSA,但5例因经济原因不愿意复查DSA.32例患者均于出院后6个月复查DSA,2例复发,其中1例弹簧圈向瘤内移位,瘤颈部位复发;复查头颅CTA的患者中1例为90％栓塞,6个月后出现瘤颈少许显影,2例患者均再次使用电解可脱式铂金螺旋圈后达100％栓塞.术后恢复良好.结论 采用电解可脱式铂金螺旋圈治疗前循环动脉瘤效果好、并发症少、恢复快,近期效果显著.     

Giant intracranial aneurysm of the anterior communicating artery treated by direct surgery using A3-A3 side-to-side anastomosis and A3-RA graft-STA anastomosis

We describe a giant aneurysm of the anterior communicating artery (ACoA) which was treated with a STA-RA graft-A3 bonnet bypass and A3-A3 side-to-side anastomosis. A giant and partially thrombosed ACoA aneurysm was partially coated 3 years before his current presentation, its gradual increase producing visual field disturbances. An A3-A3 side-to-side anastomosis and STA-RA graft-A3 bonnet bypass were performed. The aneurysm was dissected, and the thrombus removed under transient parent-artery occlusion. The aneurysmal neck was successfully clipped without encountering ischemic changes. This strategy may be useful for treating giant or thrombosed aneurysms in the region of the ACoA.     

Contralateral pterional approach to a giant internal carotid-ophthalmic artery aneruysm: technical case report

OBJECTIVE AND IMPORTANCE: The contralateral approach to internal carotid-ophthalmic artery aneurysms has been used in selected cases but has rarely been described for a giant internal carotid artery aneurysm. We report a case of giant aneurysm that was successfully clipped via the contralateral pterional approach. CLINICAL PRESENTATION: A 69-year-old woman was found to have two aneurysms: a small aneurysm at the left internal carotid-posterior communicating artery and a giant aneurysm at the right internal carotid-ophthalmic artery. INTERVENTION: A direct clipping operation was performed via the left pterional approach. After the small left internal carotid artery aneurysm was clipped, the contralateral giant aneurysm was further exposed and successfully clipped by use of the same approach via the prechiasmatic space. CONCLUSION: The contralateral pterional approach can be applied even for a giant aneurysm of the carotid-ophthalmic artery aneurysm when the neck of the aneurysm is small and when there is a space between the anterior wall of the aneurysm and the tuberculum sellae. Furthermore, such a giant aneurysm can be clipped more easily and safely via the contralateral approach without compromising visual functions. To our knowledge, this is the first reported case of a giant internal carotid-ophthalmic artery aneurysm approached contralaterally. The feasibility of this approach can be assessed preoperatively by three-dimensional computed tomographic angiography as well as by conventional cerebral angiography.     

Dorsal internal carotid artery aneurysm treated by coil embolization--case report.

A 50-year-old male presented with an extremely rare dorsal wall aneurysm of the internal carotid artery manifesting as intracerebral hemorrhage. Computed tomography demonstrated intracerebral hemorrhage on the frontal base. Magnetic resonance imaging clearly showed the hemorrhage was related to an aneurysm of the internal carotid artery. Cerebral angiography disclosed an elongated aneurysm of the dorsal wall of the internal carotid artery. The aneurysm was packed as fully as possible with Guglielmi detachable coils to achieve complete obliteration. The patient was discharged without neurological deficits. Dorsal internal carotid artery aneurysms have a high risk of premature rupture due to their unusual shape and position, adhesion to the brain tissue, and fragile neck. Direct clipping requires careful brain retraction, necessary exposure of the aneurysm, and gentle neck manipulation. Endovascular treatment is an alternative method for obliteration of the aneurysmal sac.     

Onyx in an experimental aneurysm model: histological and angiographic results

OBJECT: The use of liquid embolic agents for endovascular treatment of cerebral aneurysms is evolving. The authors' aim was to evaluate the use of Onyx HD-500 in an experimental aneurysm model and to obtain histological and angiographic long-term results. METHODS: Ten aneurysms were created using an elastase model in rabbits. The aneurysms were embolized using Onyx in combination with an inflated balloon. One animal died 1 day after embolization. The animals were divided into 2 different groups. The animals in the first group (4 rabbits) were killed at 3 months and those in the second group (5 rabbits) were killed at 6 months after embolization. A venous control angiogram was obtained, and the aneurysms were examined histologically. RESULTS: In both groups control angiograms demonstrated that all aneurysms were completely occluded. There were no signs of recanalization. Migration of Onyx was seen in 4 animals, leading to the death of 1. Histological examination not only proved the aneurysms to be occluded but also demonstrated a thin layer of endothelium at the neck of the aneurysm. The histological result was identical in both groups. CONCLUSIONS: This is the first study reporting the formation of a neointima over the neck of aneurysms embolized with Onyx in a rabbit model. Although the technique is challenging and migration of the liquid embolic agent cannot always be prevented, Onyx has a great potential to achieve a durable occlusion of aneurysms.     

A prospective single-center analysis of the safety and efficacy of the hydrocoil embolization system for the treatment of intracranial aneurysms

OBJECT: The HydroCoil embolization system is a helical platinum coil coated with a polymeric hydrogel that expands when it contacts aqueous solutions to increase filling volumes, improve mesh stability, and possibly elicit a healing response within the aneurysm. In this paper, the authors report the 1-year recurrence and complication rates of 67 aneurysms embolized with the HydroCoil system. METHODS: Sixty-four consecutive patients (67 total aneurysms) with small (< or =7 mm), large (8-15 mm), very large (16-24 mm), and giant (> or =25 mm) aneurysms in the anterior and posterior intracranial circulations were treated with HydroCoils between March 2003 and September 2004. All aneurysms were embolized by the senior author (A.S.B) with HydroCoils alone or in combination with bare platinum coils, until either there was no further angiographic contrast filling of the aneurysm or the microcatheter was pushed out of the dome by the coil mass. Balloon assistance was used in three cases and combined Neuroform stent-coil embolization in eight other cases. To evaluate the safety and 1-year efficacy of the HydroCoil system, periprocedural complications were recorded, and angiographic recurrences were categorized using the Raymond-Roy Occlusion Classification (RROC) system. The 1-year aneurysm recurrence rate independent of size was 15% in patients treated with HydroCoils. Seventy percent of the patients had stable occlusions. The recurrence rate for small aneurysms was 3.7%, and the combined recurrence rate for small and large aneurysms was 6%. Fifteen percent of the aneurysms initially categorized as RROC Type 2 or 3 with stasis of contrast material at the time of initial embolization improved in RROC type, allowing the authors to develop the aneurysm embolization grade to predict recurrence. The neurological complication rate was 14.9%, of which 4.5% represented permanent neurological deficits. CONCLUSIONS: The HydroCoil embolization system is safe and provides excellent 1-year occlusion of small and large aneurysms with initial RROC Type 1, as well as those with RROC Types 2 and 3 with stasis of contrast material at the time of embolization. Very large and giant aneurysms were not as successfully occluded with this system. Treatment of large and giant internal carotid artery aneurysms was more likely to result in cranial nerve palsies and postembolization headaches than treatment in other locations. The aneurysm embolization grade the authors developed using the results of this study accurately predicted 1-year recurrence rates based on the immediate postembolization angiographic characteristics of the treated aneurysm.     

Review of endovascular stent‐assisted embolization for management of intracranial aneurysms

Objective: This was a retrospective review of the results using stent‐assisted coil embolization for management of intracranial aneurysms. Methods: The records of seven patients treated with stent‐assisted Gugliemi detachable coil (GDC) embolization were retrieved from the authors’ prospectively maintained database. The clinical presentation, site and type of aneurysms, treatment procedure and complications, and outcome of these identified cases were reviewed. Results: Between January 2002 and May 2004, seven patients with intracranial aneurysms, four of which were ruptured, were treated by stent‐assisted GDC embolization. Four aneurysms were located at the anterior circulation and three were at the posterior circulation. The indications for stent use were: giant aneurysm (>2.5 cm), dissecting pseudo‐aneurysm, broad‐necked aneurysm and the need for preservation of important parent arteries or branches. Concerning the technical aspect, all except one had successful stent deployment. One stent dislodged after apparent successful deployment. GDC embolization was continued and the aneurysm was partially occluded. More than 90% occlusion of aneurysm sac was achieved in six aneurysms. Intraoperative complications included over‐coagulation, failure in stent deployment, displacement of stent, coil entrapment and thromboembolism. One patient had added focal neurological deficit after the procedure, and one became vegetative due to an unrelated cause. The patient in whom the stent was dislodged suffered another subarachnoid haemorrhage 4 months later and died. Conclusion: Percutaneous intracranial stent is a new and useful device to assist embolization of cerebral aneurysms that were previously not amenable to endovascular therapy. These preliminary results suggest that this procedure could achieve satisfactory outcomes without significant complications.     

Detachable balloon embolization therapy of posterior circulation intracranial aneurysms

Treatment of complex and surgically difficult intracranial aneurysms of the posterior circulation is now being performed with intravascular detachable balloon embolization techniques. The procedure is carried out under local anesthesia from a transfemoral arterial approach, which allows continuous neurological monitoring. Under fluoroscopic guidance, the balloon is propelled by blood flow through the intracranial circulation and in most cases, can be guided directly into the aneurysm, thus preserving the parent vessel. If an aneurysm neck is not present, test occlusion of the parent vessel is performed and, if tolerated, the balloon is detached. Twenty-six aneurysms in 25 patients have been treated by this technique. The aneurysms have involved the distal vertebral artery (five cases), the mid-basilar artery (six cases), the basilar artery (11 cases), and the posterior cerebral artery (four cases). The aneurysms varied in size and included three small (less than 12 mm), 15 large (12 to 25 mm), and eight giant (greater than 25 mm). Fifteen patients (60%) presented with hemorrhage and 10 patients (40%) with mass effect. In 17 cases (65%) direct balloon embolization of the aneurysm was achieved with preservation of the parent artery. In nine cases (35%), because of aneurysm location and size, occlusion of the parent vessel was performed. Complications from therapy included three cases of transient cerebral ischemia which resolved, three cases of stroke, and five deaths due to immediate or delayed aneurysm rupture. The follow-up period has ranged from 2 months to 43 months (mean 22.5 months). In cases where posterior circulation aneurysms have been difficult to treat by conventional neurosurgical techniques, intravascular detachable balloon embolization may offer an alternative therapeutic option.     

Balloon-assisted microvascular clipping of paraclinoid aneurysms. Technical note

Paraclinoid aneurysms represent a significant surgical challenge. Multiple techniques have been developed to maximize the effectiveness and safety of excluding these aneurysms from the cerebral circulation. Endovascular balloons have been used for proximal control of parent arteries during the treatment of aneurysms. In this report the authors describe the technique of navigating an endovascular balloon across the neck of paraclinoid aneurysms in four patients to gain proximal control, improve the accuracy of clip placement, and reduce the risk of distal embolization of intraluminal thrombus. Six consecutive patients with giant or complex aneurysms of the ophthalmic or paraclinoid internal carotid artery that were not amenable to endovascular obliteration were retrospectively analyzed. In all six patients, the aneurysm was exposed and dissected for microsurgical clipping, and attempts were made to navigate a nondetachable, compliant silicone balloon across the neck of the aneurysm. If successfully placed, the balloon was inflated during clip placement. In four patients, the balloon was successfully navigated across the neck of the aneurysm and was inflated during clip application. Internal carotid artery tortuosity precluded navigation of the balloon into the intracranial circulation in two patients. All aneurysms were completely excluded from the parent vessel according to postoperative angiography studies. No complication occurred as a direct result of the endovascular portion of the procedure. Endovascular balloon stenting of complex paraclinoid aneurysms during microvascular clipping may provide an adjunctive therapy that facilitates safe and accurate clip placement.     

Giant intracranial aneurysm of the anterior communicating artery treated by direct surgery using A3–A3 side-to-side anastomosis and A3-RA graft-STA anastomosis

Summary We describe a giant aneurysm of the anterior communicating artery (ACoA) which was treated with a STA-RA graft-A3 bonnet bypass and A3–A3 side-to-side anastomosis. A giant and partially thrombosed ACoA aneurysm was partially coated 3 years before his current presentation, its gradual increase producing visual field disturbances. An A3–A3 side-to-side anastomosis and STA-RA graft-A3 bonnet bypass were performed. The aneurysm was dissected, and the thrombus removed under transient parent-artery occlusion. The aneurysmal neck was successfully clipped without encountering ischemic changes. This strategy may be useful for treating giant or thrombosed aneurysms in the region of the ACoA.     

Two cases with coil embolization following incomplete neck clipping

We report two cases with embolization (coil embolization) using Guglielumi detachable coils of residual aneurysms following incomplete neck clipping. The first case, a 75-year-old woman suffered from a subarachnoid hemorrhage due to the rupture of a left internal carotid posterior communicating aneurysm in June, 1997. Neck clipping of the aneurysm was performed at day 1. Follow-up angiogram at day 7 showed a residual aneurysm involving the dome of the initial aneurysm. We performed coil embolization of the residual aneurysm following the angiogram. Almost complete obliteration of the aneurysm lasted during the follow-up period of two and a half years. The second case, a 71-year-old woman suffered from a subarachnoid hemorrhage due to the rupture of a right internal carotid posterior communicating aneurysm in May, 1999. Neck clipping of the aneurysm was performed at day 1. Follow-up angiogram at day 7 showed a residual aneurysm involving only a part of the initial aneurysm near the neck. Because no spontaneous thrombosis of the residual aneurysm was obtained after 2 months, we performed coil embolization of the residual aneurysm. Almost complete obliteration of the aneurysm lasted during the follow-up period of 7 months. These patients were discharged with good performance status. We consider the morphologic feature of the residural aneurysm to be most important for determining when to perform coil embolization of such residual aneurysms.