Digital subtraction angiography and dynamic computed tomography for evaluating the hemodynamics in cases of giant intracranial aneurysm

Dynamic computed tomography (CT) and digital subtraction angiography were used for postoperative evaluation of the hemodynamic changes in five patients with giant or large intracranial aneurysms. The lesions in four of these cases were giant or large aneurysms of the internal carotid artery, and were treated by occlusion of the cervical internal carotid artery and superficial temporal-middle cerebral artery anastomosis. The lesion in the fifth case was a giant aneurysm of the right vertebral artery, which was treated by proximal clipping of the vertebral artery. Preoperative digital subtraction angiography revealed aneurysmal staining, and dynamic CT scanning indicated the rapid transit of contrast medium in the dome of the aneurysm. Dynamic CT scanning immediately after operation indicated a low flow state in all of the aneurysms, suggesting that they were thrombosed. Although within a few months the peripheral edges of the aneurysms became enhanced, dynamic CT scanning revealed a slower transit of contrast medium through the centers of the aneurysms than in the basilar artery, and digital subtraction angiography failed to demonstrate aneurysmal staining, suggesting that the aneurysms remained thrombosed. The present data indicate that dynamic CT scanning and digital subtraction angiography may be useful for relatively noninvasive evaluation of the hemodynamic changes in patients with giant intracranial aneurysms.     

Surgery for giant intracranial aneurysms using advanced technology

PURPOSE: Outcome of surgery for giant intracranial aneurysms is still unsatisfactory. The reason for complications is occlusion of perforators or parent arteries by the aneurysmal clipping itself or temporary occlusion of the main arteries. We report the surgical outcome of treatment of giant aneurysms using several advanced techniques which we devised to prevent these complications. MATERIALS AND METHODS: The subjects were eight patients with giant intracranial aneurysms who underwent surgery during the recent five years. Six patients had ruptured and two had unruptured aneurysms. Aneurysms were located at the ICA in five and the MCA in three patients. Aneurysmal sizes ranged from 25 to 50 mm. Preoperative 3DCTA was performed to investigate the aneurysm and the surrounding vessels in all cases. Patients with unruptured aneurysms at the ICA underwent balloon occlusion tests to check the potential for safe temporary occlusion of the parent artery, with SEP monitoring and Xe-SPECT. Intraoperative angiography and neuroendoscopes were used to prevent problems and complications which might be caused by aneurysmal clipping. RESULTS: In seven of eight cases, the aneurysmal neck was completely obliterated with clips and in one case the aneurysm was trapped with STA-MCA anastomosis. Glasgow Outcome Scale of the patients showed good recovery in six, moderately disabled (MD) in one and dead in one. The patient demonstrating MD developed hemiparesis due to vasospasm. One patient died from rebleeding of the aneurysm caused by slippage of the aneurysmal clip despite the confirmation of complete obliteration by intraoperative angiography. CONCLUSIONS: A better surgical outcome of treatment for giant aneurysms was obtained by temporary clips whose placement was based on the results of balloon occlusion test, as well as the use of intraoperative angiography and neuroendoscopes.     

Presurgical selection of the ideal aneurysm clip by the use of a three-dimensional planning system

Aneurysm occlusion rate after clipping is higher than after endovascular treatment. However, a certain percentage of incompletely clipped aneurysms remains. Presurgical selection of the proper aneurysm clips could potentially reduce the rate of incomplete clippings caused by inadequate clip geometry. The aim of the present study was to assess whether preoperative 3D image-based simulation allows for preoperative selection of a proper aneurysm clip for complete occlusion in individual cases. Patients harboring ruptured or unruptured cerebral aneurysms prior to surgical clipping were analyzed. CT angiography images were transferred to a 3D surgical-planning station (Dextroscope®) with imported models of 58 aneurysm clips. Intracranial vessels and aneurysms were segmented and the virtual aneurysm clips were placed at the aneurysm neck. Operating surgeons had information about the selected aneurysm clip, and patients underwent clipping. Intraoperative clip selection was documented and aneurysm occlusion rate was assessed by postoperative digital subtraction angiography. Nineteen patients were available for final analysis. In all patients, the most proximal clip at the aneurysm neck was the preselected clip. All aneurysms except one were fully occluded, as assessed by catheter angiography. One aneurysm had a small neck remnant that did not require secondary surgery and was occluded 15 months after surgery. 3D image-based preselection of a proper aneurysm clip can be translated to the operating room and avoids intraoperative clip selection. The associated occlusion rate of aneurysms is high.

     

Limitations of three-dimensional reconstructed computerized tomography angiography after clip placement for intracranial aneurysms

OBJECT: The authors compared the usefulness of three-dimensional (3D) reconstructed computerized tomography (CT) angiography with 3D digital subtraction (DS) angiography in assessing intracranial aneurysms after clip placement. A retrospective review of clinical cases was performed. METHODS: Between May 2001 and May 2003, 17 patients with a total of 20 intracranial aneurysms underwent 3D CT and 3D DS angiography following clip placement. The authors assessed the presence or absence of residual aneurysm necks and stenoocclusive changes in the parent artery and the neighboring artery. The efficacy of CT angiographic visualization was also evaluated. In 12 of the 20 aneurysms, both 3D modalities similarly demonstrated the residual aneurysm neck and stenoocclusive changes in the parent artery and neighboring artery. Three-dimensional CT angiography failed to demonstrate three of the aneurysms, and the studies were not considered suitable for evaluation because of the presence of metallic artifacts. In the remaining five studies, the 3D CT angiograms did not effectively demonstrate the neighboring and parent arteries. The detectability of residual aneurysm necks was correlated with the clip material and with the number of clips applied. CONCLUSIONS: Three-dimensional DS angiography is still necessary in cases involving multiple clips or with cobalt alloy clips because the clips appear as metal artifacts on 3D CT angiography.     

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.     

Anterior communicating artery aneurysm in the sella turcica: case report

BACKGROUND: Only 3 such reported intrasellar aneurysms have arisen from the anterior communicating artery. CASE DESCRIPTION: A neurologically normal 38-year-old man complaining of headache underwent cranial magnetic resonance imaging, which showed a heterogeneously enhancing, partially calcified intrasellar mass. The normal pituitary gland was identified at the bottom of the sella, and the optic chiasm was located superior to the aneurysm. Digital subtraction angiography and three-dimensional computed tomography angiography demonstrated the mass to be a partially thrombosed anterior communicating artery aneurysm. Frontotemporal craniotomy was performed, but initial attempts to occlude the neck of the aneurysm were unsuccessful. We could not expose the dome of the aneurysm or confirm the anatomic relationship of the pituitary to the aneurysm. The patient declined further intervention, and close follow-up has been maintained. CONCLUSION: Our case suggested that unlike intrasellar aneurysms arising from the internal carotid artery, intrasellar aneurysms originating from the anterior communicating artery are likely to present difficulty in dissecting the neck of the aneurysm from the bilateral optic nerves and pituitary stalk, impeding direct aneurysm clipping. When we operated upon a patient with a large unruptured intrasellar aneurysm originating from the anterior communicating artery via the prechiasmatic space, we encountered considerable technical difficulty.     

Extracorporeal femoral to carotid artery perfusion in selective brain cooling for a giant aneurysm. Case report

Giant partially thrombosed intracranial aneurysms are a challenge to treat surgically, and they are also unsuitable for coil embolization. The current options for treatment include extracranial-intracranial bypass followed by parent artery occlusion or direct surgical occlusion in which deep hypothermic circulatory arrest is used. The authors report the use of another approach in the treatment of a giant anterior circulation aneurysm: selective brain cooling accomplished by extracorporeal perfusion. This facilitated direct surgery on a 4.2-cm, partially thrombosed aneurysm of the middle cerebral artery (MCA). A brain temperature of 22 degrees C was achieved after 20 minutes of perfusion with blood cooled using an extracorporeal technique of femoral-common carotid artery perfusion. This was followed by a 20-minute period of surgical trapping of the MCA, then evacuation and clip occlusion of the aneurysm. During the period of selective brain cooling the patient's core body temperature was maintained above 35 degrees C. This technique of selective brain cooling may be a useful alternative to currently available surgical and endovascular methods of treatment for giant aneurysms.     

Giant pericallosal artery aneurysm: case report and review of the literature

Pericallosal artery aneurysms comprise 5% of all intracranial saccular aneurysms and are usually small. Giant cerebral aneurysms mostly occur in major arteries. To date, 12 cases of giant pericallosal artery aneurysm have been reported in the literature. An unusual giant thrombosed pericallosal artery aneurysm is reported here. A 65-year-old female presented with headache and personality changes. Computed tomography, magnetic resonance imaging, and cerebral angiography revealed a right-sided giant thrombosed pericallosal artery aneurysm. The patient was operated via an anterior interhemispheric approach and the neck of the aneurysm was successfully clipped. The postoperative period was uneventful. This rare lesion is one of few cases presented in the literature in which neuroradiologic and neuropathologic evaluation was completely performed and the neck of the aneurysm was clipped. Received: 14 November 2000 / Accepted: 4 January 2000     

多技术联合应用于颅内巨大动脉瘤的显微外科治疗

目的 探讨神经电生理监测、术中超声、术中荧光造影、神经内镜多技术联合应用于颅内巨大动脉瘤的显微外科手术治疗的临床效果。方法 回顾性分析显微手术治疗颅内巨大动脉瘤17例的临床资料。术前采用3D-CTA、MRI和DSA,充分评估动脉瘤的位置、大小和形状。术中应用神经电生理监测评价动脉瘤夹闭前、后的神经功能保留和损害程度;通过微血管多普勒超声的定性和定量分析联合术中荧光造影评定动脉瘤和周围邻近血管的血液流速及通畅度;神经内镜观察动脉瘤区的局部解剖,辨认重要的穿支血管、瘤颈结构和动脉瘤夹情况。手术在手术显微镜下操作,采用载瘤动脉控制性技术、瘤颈成形技术、动脉瘤内减压和切除技术、多瘤夹夹闭技术和血管痉挛保护技术等进行联合治疗。 结果 在多技术联合监测下,显微外科手术成功夹闭巨大动脉瘤17个,术后恢复良好15例,出现轻偏瘫1例,重度偏瘫l例,无死亡病例。DSA复查示瘤颈夹闭完全,载瘤动脉通畅。远期随访仍在进行中。 结论 多技术联合显微手术技术,能有效提高颅内巨大动脉瘤的手术疗效。     

Tailored flow sequestration treatment using high-flow and low-flow bypass for partially thrombosed giant internal carotid artery aneurysm—a technical case report

Direct clipping of giant partially thrombosed intracranial internal carotid artery (ICA) aneurysms is challenging, especially when important perforating arteries are involved. Proximal occlusion with bypass represents a possible alternative approach. An 80-year-old female presented with worsening visual acuity and severe headache caused by partially thrombosed giant (38 mm in diameter) aneurysms of the right ICA, suggestive of impending rupture. Direct clipping in conjunction with temporary occlusion of the lesion involving the anterior choroidal artery (AChA) was considered too risky. Thus, we sequestrated the ipsilateral ICA flow into a low-flow and a high-flow system using two external carotid artery (ECA)-ICA bypasses and one in situ bypass with cervical ICA ligation. As a result, the low-flow system by the superficial temporal artery-middle cerebral artery (MCA) bypass perfused mainly the proximal MCA lesions and aneurysm, whereas the high-flow system by ECA-radial artery-M2 bypass exclusively supplied the residual distal MCA area. This tailored flow sequestration successfully interrupted intra-aneurysmal flow and accelerated near-complete thrombosis of the aneurysm while preserving the AChA and avoiding any significant neurological deterioration. We conclude that this method is effective for the management of giant partially thrombosed aneurysms of the ICA, especially when direct clipping is difficult.     

Treatment of intradural paraclinoidal aneurysms

Intradural paraclinoidal aneurysm still presents conceptual confusion and technical surgical problems. The clinical features of 68 consecutive patients with paraclinoidal aneurysms were analyzed. The pterional approach was used in all patients. Subarachnoid hemorrhage (SAH) occurred in 37 patients from the paraclinoidal aneurysm and in 10 patients from another associated aneurysm. Thirty-four of the 37 ruptured paraclinoidal aneurysms were clipped, two blister-like aneurysms required trapping, and one blister-like aneurysm was coated. Thirteen of the 31 unruptured paraclinoidal aneurysms, consisting of 10 with ruptured associated aneurysm, four symptomatic, and 17 incidental, were clipped and 18 were coated. Favorable outcomes were obtained in 38 of 47 patients with SAH and 17 of 21 patients without SAH. Nine unfavorable outcomes in SAH patients were caused by primary brain damage (5), vasospasm (2), cerebral infarction after trapping (1), and pneumonia (1). All four unfavorable outcomes in non-SAH patients were due to surgical procedures for giant aneurysms or associated basilar artery aneurysm. Removal of the anterior clinoid process was performed to secure the proximal neck in 15 patients with large or giant aneurysms. Multiple clips with or without fenestrated clips were required in all giant aneurysms, and exposure of the cervical internal carotid artery (ICA) in 17 giant or large aneurysms. Fenestrated clips were also useful for one small aneurysm projecting posteriorly. A favorable outcome was achieved in 17 of 19 patients undergoing coating. Coating without clipping might be better for some blister-like ICA aneurysms, even if ruptured. Paraclinoidal aneurysms can be clipped with favorable results using these techniques except for giant aneurysms and associated basilar artery aneurysm.     

双能量CT血管成像在颅内动脉瘤钛夹夹闭术后随访中的应用

目的探讨双能量CTA(DECTA)在颅内动脉瘤夹闭术后随访中的价值。方法对77例临床确诊为颅内动脉瘤并接受动脉瘤钛夹夹闭术的患者行DECTA检查,将原始数据传至后处理工作站进行图像重组,采用原始轴位图像与重建图像相结合的方式进行综合分析。结果 77例中,DECTA均能清晰显示动脉瘤夹闭情况、动脉瘤钛夹及载瘤动脉与其他颅内主要大血管的通畅情况;共84个动脉瘤接受手术夹闭,其中颅内动脉瘤完全夹闭82个,均未发生移位,动脉瘤颈残留2个;3例动脉瘤夹闭术后其他部位出现新发病灶,1例载瘤动脉血管纤细狭窄。结论 DECTA可作为颅内动脉瘤患者动脉瘤钛夹夹闭术后准确、无创的影像学随访方法。     

Complete neck clipping of internal carotid-posterior communicating artery aneurysms using bayonet-shaped aneurysm clips: technical note

Neck clipping for internal carotid-posterior communicating artery (IC-PC) aneurysms using standard straight, angled, or curved clip may result in remnant aneurysm neck. We describe complete neck clipping of IC-PC aneurysms using a bayonet-shaped clip. The bayonet-shaped clip is applied perpendicular to the long axis of the internal carotid artery (ICA), and the blades of the clip are inserted between the aneurysm neck and the ICA. Using the clip applicator, the clip is gradually rotated counterclockwise or clockwise for left or right ICA aneurysm, respectively, so that the distal and shank portions of the clip blade are located at the aneurysm neck in the posterior communicating artery (Pcom) and ICA, respectively. As a result, the distal flexure of the clip blade fits the junction of the ICA and Pcom. This technique was used in four patients with ruptured ICA aneurysms and five patients with unruptured ICA aneurysms. Postoperative cerebral angiography demonstrated no residual aneurysm neck and preservation of the Pcom in all patients. This technique is useful for cases of IC-PC aneurysm involving the origin of the Pcom.     

颅底Willis环前部大或巨大动脉瘤的手术治疗

目的 研究３Ｄ－ＣＴＡ的诊断技术和改进显微外科手术技术,以提高Ｗｉｌｌｉｓ环前部大或蔬大动脉瘤的手术疗效。方法 回顾性分析作者自１９８５年１０月至１９９８年１２月手术治疗Ｗｉｌｌｉｓ前部环大、巨大动脉瘤２８例。在诊断上,术前采用３Ｄ－ＣＴＡ以发现和勾划动脉瘤,并与ＤＳＡ对照。在手术上采用颅底入路、近准则载瘤动脉暂时性阻断、动脉瘤内减压、多瘤夹夹闭、瘤颈逐步缩窄、动脉瘤切除等技术。结果 出院时优良者     

Clip blade scissoring with titanium bayonet clip in aneurysm surgery. Two case reports

Scissoring of the cerebral aneurysm clip blades is a rare but potentially devastating complication of clipping surgery and results in aneurysm neck injury inducing rupture and/or cerebral infarction. Scissoring has been reported using titanium straight clips. Here we present two unusual cases of crossing of the blades of titanium bayonet clips by a scissors-like mechanism during surgery. The present cases suggest the following points. Bayonet clips in addition to straight clips may display the scissoring phenomenon during clipping surgery. The slipped clip should be removed immediately because the scissor-like deformed aneurysm clip may slip further and result in parent artery stenosis. Scissoring tends to happen in the presence of partial arteriosclerosis of the aneurysm neck. Before a titanium clip is used to treat an aneurysm with partially arteriosclerotic neck, reducing the amount of aneurysm filling by temporary clipping of the main vessel is useful to avoid slippage phenomena.     

Microsurgical removal of previously placed aneurysm clips and application of new clips for recurrent cerebral aneurysms. Technical note

A technique is described for removing previously placed aneurysm clips and applying new aneurysm clips for the treatment of regrown or reruptured cerebral aneurysms in patients more than 10 years after the original clipping of the aneurysm neck. The adherent tissue covering previously placed clips is cut just on and alongside the clips themselves using a small scalpel. Using the clip applicator, gentle pressure is applied to open the clip blade as little as possible. The aneurysm clip is carefully slid out along the line where the clip blade has resided, and a new aneurysm clip is applied. The procedure was successfully accomplished in four patients. Whereas three of these patients had an uneventful postoperative course, the remaining patient experienced transient right oculomotor nerve palsy and left-sided motor weakness. The present technique is a useful procedure for treatment of regrown or reruptured cerebral aneurysms occurring a significantly long time after initial clipping of an aneurysm neck.     

The rubber dam interposition technique during intracranial aneurysm clipping under deep hypothermic circulatory arrest

OBJECTIVE: We describe a technique for isolating perforating arteries by use of a rubber sheet during the clipping of intracranial aneurysms under deep hypothermic circulatory arrest. METHODS: After meticulous dissection of the perforating arteries from the aneurysm, a rubber sheet, cut from a surgical glove to the proper shape, is inserted between the aneurysm and the arteries to prevent arterial reattachment to the aneurysmal neck. RESULTS: Even when perforators are invisible at the time of neck clipping because of a large aneurysmal body, the blade of the clip slides along the rubber sheet without injuring the vessels. CONCLUSION: With this method, an aneurysm, especially a large or giant one, can be clipped easily and safely even when the patient is in deep hypothermic circulatory arrest.     

Open surgery of giant paraclinoid aneurysms improved by intraoperative angiography and endovascular retrograde suction decompression

Summary In three consecutive cases of giant left sided paraclinoid aneurysms we employed an endovascular retrograde suction decompression technique in combination with intra-operative angiography. A double-lumen balloon catheter was placed in the left internal carotid artery by the transfemoral route. After balloon inflation and placement of a temporary clip distal to the aneurysm blood was aspirated and the aneurysm collapsed. Thus further dissection of the aneurysm could easily be achieved and clips could be placed. Afterwards real-time digital subtraction angiography was performed. Intra-operative angiography led to clip repositioning in all cases either due to a clip induced stenosis of the parent vessel, or because of incomplete aneurysm obliteration. Afterwards successful clipping could be confirmed in all cases. Outcome was excellent in one case, good in the other. The third case, extremely complicated by an accompanying craniopharyngioma, showed a satisfactory outcome, but presented new neurological deficits.     

Treatment of unclippable giant posterior cerebral artery aneurysms with detachable balloons--report of three cases.

Three patients presented with rare giant posterior cerebral artery aneurysms, clinically manifesting as cerebral ischemia, mass effect, and subarachnoid hemorrhage. All aneurysms were partially thrombosed, originated at the P2 segment, and possessed broad necks. Surgical neck clipping was difficult but proximal occlusion of the parent artery was feasible. Aneurysm occlusion sparing the parent artery was attempted in all cases, but failed because the detachable balloon did not successfully block the aneurysmal neck. All patients tolerated test occlusion at the P2 segment, so the parent artery was occluded proximally with detachable balloons, leaving the important perforating arteries unaffected. Two transient ischemic attacks were associated with the procedure. Where surgical treatment is unusually difficult, and proximal ligation or trapping just feasible, embolization with detachable balloons is an acceptable substitute.     

A combination of wrapping and clipping using a collagen-impregnated dacron fabric (Hemashield)

BACKGROUND: We describe techniques combining wrapping and clipping using a collagen-impregnated Dacron knitted fabric (Hemashield) for accidental arterial perforations and broad-based aneurysms. The results of these techniques in seven patients are presented. METHODS: Clip-reinforced wrapping was performed to obtain hemostasis in two patients with arterial perforations and in a patient with a ruptured broad-based aneurysm in the internal carotid artery. Clipping of the broad neck of the aneurysm and wrapping with Hemashield (wrap-clipping) was performed in four patients with unruptured aneurysms (one internal carotid artery, two middle cerebral artery, one basilar artery). RESULTS: In the three patients treated with clip-reinforced wrapping, complete hemostasis was obtained just after clip application. In the patient with a ruptured broad-based aneurysm, postoperative angiography demonstrated that the dome of the aneurysm was well compressed. In the four patients treated with wrap-clipping, postoperative angiography revealed successful clipping of the broad neck of the aneurysm. CONCLUSION: In this early experience, there were no problems in the use of Hemashield for clip-reinforced wrapping or wrap-clipping.