Intraoperative endovascular surgery for cerebral aneurysms

Endovascular treatment of previously clipped aneurysms: continued evolution of hybrid neurosurgery

Background/objective

The optimal management of residual or recurrent clipped aneurysms is infrequently addressed in the literature.

Methods

We reviewed our endovascular database from January 1998 to May 2016 to identify patients with clipped aneurysms undergoing subsequent endovascular treatment, evaluating treatment approach, and clinical and angiographic outcomes.

Results

60 patients underwent endovascular treatment of residual/recurrent clipped aneurysms; 7 rebled prior to endovascular therapy. Treatment was via coiling alone (n=25, 42%), stent assisted coiling (n=15, 25%), balloon assisted coiling (n=8, 13%), flow diversion (n=8, 13%), stenting alone (n=3, 5%), or flow diversion with coiling (n=1, 2%). The procedural permanent neurological morbidity and mortality rates were 3% and 2%, respectively. Over a clinical follow-up of 253.4 patient years (median 3.9 years), there was one rebleed in a patient who had declined further treatment. For 43 patients with at least 1 month of digital subtraction angiographic follow-up (median 3.4 years), complete aneurysm occlusion was seen in 79% of cases. Neck remnants were observed in 14%, and stable small dome remnants were observed in 7% of cases. In a subgroup of 18 patients with ‘clip induced’ narrow neck aneurysms, all domes were initially coil occluded (Raymond 1 or 2); there was no permanent procedural morbidity and no aneurysms required retreatment or recanalized over a median follow-up of 3.9 years.

Conclusions

Endovascular treatment of residual or recurrent clipped aneurysms is an excellent treatment approach in well selected patients; ‘clip induced’ narrow neck aneurysms fare particularly well after treatment both angiographically and clinically.

Clinical analysis of giant intracranial aneurysms with endovascular embolization

Objective

The purpose of this study was to perform a clinical analysis of nine patients with giant aneurysms managed with endovascular embolization.

Methods

From March 2000 to September 2009, nine cases of giant intracranial aneurysms were treated (five unruptured and four ruptured). The nine patients included two males and seven females who were 47 to 72 years old (mean, 59.2 years old). The types of giant intracranial aneurysms were eight internal carotid artery aneurysms and one vertebral artery aneurysm. Treatment for each aneurysm was chosen based on anatomic relationships, aneurysmal factors, and the patients' clinical state. Three patients underwent endovascular coiling with stent and six initially underwent endovascular coiling alone. Medical records, operation records, postoperative angiographies, and follow-up angiographies were reviewed retrospectively.

Results

Eight out of nine patients showed good clinical outcomes. (six were excellent and two were good) after a mean follow-up period of 27.9 months. Six (67%) of the nine patients had a near-complete occlusions on the post-operative angiogram (mean, 13.5 months after the procedure). Occlusion rates of 90% or higher were obtained for eight (89%) of all the patients. One patient died due to multiple organ failure. Stents were ultimately required at some point for managing four aneurysms. Two patients needed additional procedures because of aneurysm regrowth.

Conclusion

Endovascular treatment could be an alternative option for managing giant aneurysms adjuvant to surgical intervention.

Moyamoya disease associated with basilar tip aneurysm

Direct surgical intervention to treat ruptured basilar tip aneurysms in patients with moyamoya disease has rarely been attempted, and patients who have undergone such treatment have not fully recovered. We review six cases of surgically treated ruptured basilar tip aneurysm associated with moyamoya disease, including our own case to illustrate aspects of surgical intervention and the difficulties encountered. Patients who underwent surgery after 4 weeks of the onset of symptoms showed impressive results. Of the patients who underwent surgery in the acute stage, two died, including our patient, and one showed excellent recovery. It is emphasized that to achieve satisfactory surgical outcome, the following factors should be considered: (i) delayed operation is preferable, with extracranial-intracranial bypass in selected patients; (ii) careful preservation of moyamoyas and transdural collaterals is mandatory; (iii) intraoperative rupture of the aneurysm should be avoided; and (iv) using a neuroanaesthetic technique of induced hypothermia and hypertension may be preferable.

Endovascular retrograde suction decompression as an adjunct to surgical treatment of ophthalmic aneurysms: analysis of risks and clinical outcomes

OBJECTIVE

Endovascular retrograde suction decompression with balloon occlusion of the internal carotid artery is a useful adjunct in the surgical treatment of ophthalmic aneurysms. This technique helps establish proximal control, facilitates intraoperative angiography, and may aid dissection by evacuating blood and softening the aneurysm. Although the technical aspects of this procedure have been described, the published data on its safety are scant. This study analyzed 2 groups of patients who underwent craniotomies for treatment of ophthalmic aneurysms, comparing a group who received suction decompression with a group who did not.

METHODS

A retrospective analysis of prospectively collected data on 118 craniotomies for ophthalmic aneurysms performed from 1990 to 2005 is presented. A group of 63 patients treated with endovascular suction decompression during surgery is compared with 55 patients who did not undergo this technique.

RESULTS

In our overall analysis of ophthalmic aneurysms, the clinical outcome was statistically related to aneurysm size (P = 0.046). The endovascular suction decompression group in this study had overall larger aneurysms (P < 0.0001) compared with the other group. There was no statistical difference between the 2 groups in rates of complications, stroke, new visual deficit, or death. The clinical outcomes were statistically similar at discharge and at 1 year.

CONCLUSION

Endovascular balloon occlusion and suction decompression did not increase the complication rate in a large cohort of craniotomy patients with ophthalmic aneurysms. This technique may be used to augment surgical capabilities without significantly increasing the operative risk.

Spontaneous thrombosis of a giant fusiform aneurysm following extracranial-intracranial bypass surgery

The authors describe the cases of 2 patients who underwent extracranial-intracranial bypass surgery for a giant fusiform aneurysm but in whom further surgery was then not necessary because the aneurysm spontaneously thrombosed. The authors hypothesize that this thrombosis was caused by alterations in aneurysm's hemodynamics, leading to a decreased rate of blood flow in the aneurysm. In the older of the 2 cases, more than 10 years after surgery the patient has not required further surgical intervention. Spontaneous thrombosis of a giant fusiform aneurysm is a rare occurrence during extracranial-intracranial bypass, and although continual monitoring is recommended, these patients can remain stable long term.

RESULTS, OUTCOMES, AND FOLLOW-UP OF REMNANTS IN THE TREATMENT OF OPHTHALMIC ANEURYSMS

OBJECTIVE

Ophthalmic aneurysms present unique challenges to a vascular team. This study reviews the 16-year experience of a multidisciplinary neurovascular service in the treatment, complications, outcomes, and follow-up of patients with ophthalmic aneurysms from 1990 to 2005.

METHODS

A retrospective analysis of prospectively collected data of 134 patients with 157 ophthalmic aneurysms is presented. Subgroup analysis is performed based on treatment and clinical presentation of the patients.

RESULTS

Clinical outcomes are reported using the Glasgow Outcome Scale. A “good” outcome is defined as a Glasgow Outcome Scale score of 4 or 5, and a “poor” outcome is defined as a Glasgow Outcome Scale score of 1 to 3. Outcome was related to patient age (P = 0.0002) and aneurysm size (P = 0.046). Outcomes for patients with ruptured aneurysms were related to hypertension (P &lt; 0.0001) and clinical admission grade (P = 0.001). In patients with unruptured aneurysms, a good clinical outcome was noted in 103 (92.7%) of 111 patients at discharge and 83 (94.3%) of 88 patients at the time of the 1-year follow-up evaluation. Complete clipping was attained in 89 (79.5%) of 112 patients with angiographic follow-up. Patients with aneurysm remnants from both coiling and clipping had a low risk of regrowth, and there were no rehemorrhages. One of 25 patients with angiographic follow-up (average, 4.3 ± 4.1 years) after “complete” clipping showed recurrence of the aneurysm.

CONCLUSION

Despite the difficulties presented by ophthalmic aneurysms, these lesions can be successfully managed by a multidisciplinary team. Imaging follow-up of patients is important, as there is a risk of aneurysm regrowth after either coiling or clipping.

Methods and application areas of endoscopic optical coherence tomography

We review the current state of research in endoscopic optical coherence tomography (OCT). We first survey the range of available endoscopic optical imaging techniques. We then discuss the various OCT-based endoscopic methods that have thus far been developed. We compare the different endoscopic OCT methods in terms of their scan performance. Next, we examine the application range of endoscopic OCT methods. In particular, we look at the reported utility of the methods in digestive, intravascular, respiratory, urinary and reproductive systems. We highlight two additional applications--biopsy procedures and neurosurgery--where sufficiently compact OCT-based endoscopes can have significant clinical impacts.

Selective intraoperative angiography in intracranial aneurysm surgery: intraoperative factors associated with aneurysmal remnants and vessel occlusions

BACKGROUND

The objective of this study was to assess the role of selective intraoperative angiography and to analyze the factors associated with faulty clip application.

METHODS

Two hundred thirty-eight patients undergoing surgery for intracranial aneurysms were studied consecutively for intraoperative angiography (IOA)-related events. The procedure was performed in 155 operations. Demographic details, clinical grade of the patient, location and size of the aneurysm, intraoperative rupture, application of the temporary clip, IOA findings, and final outcome were analyzed.

RESULTS

In the 155 patients in the series, there were 125 anterior circulation aneurysms and 30 on the vertebrobasilar system. Aneurysms were smaller than 10 mm in 63% of the patients, and 19 were giant aneurysms. Thirty-eight percent were unruptured, 36% were Hunt and Hess Grades I and II, 21% were Grade III, and 5% were Grades IV and V. An intraoperative rupture occurred in 18 operations. Intraoperative angiography was normal in 88%; in 11 cases (7%) there was a residual neck, and in 8 (5%), occlusion of the artery was observed. An incomplete clipping was significantly related to intraoperative rupture of the aneurysm (p < 0.008) and anterior location of the aneurysm (p = 0.05), whereas vessel occlusion had a significant association with posterior location of the aneurysm (p < 0.0005). An eventful IOA had significant association with poor outcome (p < 0.003).

CONCLUSION

Intraoperative rupture and a posterior location of the aneurysm had a significant correlation with residual aneurysm and vessel occlusion, respectively. The use of IOA is justified in aneurysms associated with these factors.

Endovascular treatment of distally located giant aneurysms

OBJECTIVE

Because giant aneurysms (GAs) can be technically difficult to clip, the endovascular approach is becoming increasingly popular. Endovascular treatment of distally located GAs, which often requires parent vessel occlusion, is particularly challenging because limited pathways are available for collateral flow. We aimed to determine the outcomes of endovascular attempts to treat GAs downstream from the circle of Willis.

METHODS

Between 1991 and 1998, 27 patients with 27 distally located very large aneurysms or GAs were evaluated for possible endovascular treatment. Ten underwent selective embolization and 9 were treated with primary parent vessel occlusion, with or without distal bypass. Eight patients could not be treated endovascularly.

RESULTS

Selective embolization resulted in only one cure. Two patients died as a result of subarachnoid hemorrhage during the follow-up period. One coil-treated patient, who underwent subsequent spontaneous parent vessel occlusion, and all nine patients treated primarily with parent vessel occlusion were considered cured after their treatments. Only two patients treated with parent vessel occlusion experienced periprocedural ischemia, which did not result in a major deficit in either case. Of the eight patients who could not be treated endovascularly, one succumbed to surgery, four died while being treated conservatively, and three were lost to follow-up monitoring.

CONCLUSION

Selective aneurysm embolization is usually not curative in these situations. For selected patients, however, endovascular parent vessel occlusion is usually safe and effective in preventing the progression of symptoms and bleeding.

Early aneurysm recurrence after technically satisfactory Guglielmi detachable coil therapy: is early surveillance needed? Case report

Guglielmi detachable coil (GDC) therapy was initially intended as a treatment for select patients harboring aneurysms deemed to be at high risk for clip ligation. As experience with the technique has grown, many centers are now offering GDC therapy as a primary treatment to patients who are also good surgical candidates. The authors report a case in which a ruptured anterior communicating artery aneurysm recurred within 2 weeks of a technically satisfactory GDC procedure. The patient subsequently underwent successful surgery for clip ligation of the lesion. This is the earliest reported recurrence of an aneurysm after angiographically confirmed successful GDC therapy and underscores the need for performing early control angiography in patients undergoing this procedure.

Development of a handpiece and probes for a microsurgical ultrasonic aspirator: instrumentation and application

OBJECTIVE

To address the several disadvantages of currently available ultrasonic aspirators used in microsurgery, new instruments were designed for neurosurgical use under a microscope.

DESCRIPTION OF INSTRUMENTATION

The weight of the handpiece was reduced to 90 g. Two types of angled probes were constructed. Keyhole-type probes have 93- and 112-mm lengths, a 2.2-mm tip diameter, and 9.5- and 11.2-mm sheath diameters at the most proximal site and produce a tip amplitude of 300 microm (supplied by 23.5-kHz ultrasonic power). Needle-type probes have 89- and 171-mm lengths, a 1.9-mm tip diameter, and 3.5- and 3.3-mm sheath diameters at the proximal site and produce a tip amplitude of 70 microm. All of these instruments are compatible with magnetic resonance imaging.

METHODS

The newly developed handpiece and probes were used in an experimental model. The 119 mass lesions treated included giant thrombosed aneurysms, various gliomas, vestibular schwannomas, deep-seated meningiomas, clival tumors, and suprasellar tumors.

EXPERIENCE AND RESULTS

The handpiece and probes were safely used in regions that are difficult to access, such as the third ventricle and the cerebellopontine angle. It was possible to manipulate the needle-type probe in the suprasellar region through the transsphenoidal route, and the probe was very efficient for thrombectomy in giant aneurysms. The ultrasonic power of keyhole-type probes was sufficient to remove meningiomas.

CONCLUSION

This newly developed neurosurgical handpiece with angled probes has great utility for microscopic dissections, because of its small size and light weight.

A combined microsurgical skull-base and endovascular approach to giant and large paraclinoid aneurysms

BACKGROUND

The treatment of giant and large paraclinoid aneurysms remains challenging. To improve exposure, facilitate the dissection of aneurysms, assure vascular control, reduce brain retraction and temporary occlusion time, enable simultaneous treatment of associated lesions, and achieve more successful treatment of "difficult" (atherosclerotic and calcified) aneurysms, we combined the skull-base approach with endovascular balloon occlusion of the internal carotid artery (ICA) and suction decompression of the aneurysm.

METHODS

Sixteen female patients were treated, eight with giant aneurysms and eight with large aneurysms. Eight aneurysms occurred on the right side and eight on the left. Eight patients had an additional aneurysm; five were clipped during the same procedure. Three patients had infundibular arterial dilation. One patient had an associated hemangioma of the ipsilateral cavernous sinus. The cranio-orbital-zygomatic approach was used for all patients. The anterior clinoid was drilled, and the optic nerve was decompressed, dissected, and mobilized. Transfemoral temporary balloon occlusion of the ICA in the neck was followed by placement of a temporary clip proximal to the posterior communicating artery. Suction decompression was then applied. All aneurysms were then successfully clipped, except one that had a calcified neck and wall that could not be collapsed. Intraoperative angiography performed in 13 of 15 patients with clipped aneurysms confirmed obliteration of the aneurysm and patency of the blood vessels.

RESULTS

Postoperative results were good in 14 patients. One patient had right-sided hemiplegia and expressive aphasia, which improved after rehabilitation. One patient with an additional basilar tip aneurysm clipped simultaneously died on the fifth postoperative day because of intraventricular hemorrhage. The origin of bleeding could not be determined on autopsy. Surgical difficulties and morbidity stemmed mainly from a severely calcified or atherosclerotic aneurysmal neck.

CONCLUSION

The combination of skull-base approaches and endovascular balloon occlusion coupled with suction decompression is a successful option for the treatment of these challenging aneurysms.

Complex intracranial aneurysms: combined operative and endovascular approaches

OBJECTIVE

Endovascular management of complex intracranial aneurysms is increasingly being considered as an alternative to standard surgical clipping. However, little attention has been paid to the complementary nature of surgery and endovascular therapy.

METHODS

Between September 1992 and May 1997, 12 patients with complex intracranial aneurysms were treated with combined operative and endovascular methods. Seven patients demonstrated subarachnoid hemorrhage (two of Grade II, two of Grade III, and three of Grade IV). Five patients demonstrated unruptured aneurysms, i.e., three giant aneurysms (one vertebrobasilar junction aneurysm, one middle cerebral artery bifurcation aneurysm, and one internal carotid artery-ophthalmic artery aneurysm), one large internal carotid artery-ophthalmic artery aneurysm, and one middle cerebral artery serpentine aneurysm. Management strategies involved either surgery followed by endovascular therapy (S-E; n = 5) or endovascular therapy followed by surgery (E-S; n = 7). S-E paradigms included aneurysm exploration followed by endovascular treatment (S-E1; n = 3), partial aneurysm clipping followed by endovascular aneurysm packing (S-E2; n = 1), and extracranial-to-intracranial bypass followed by endovascular parent vessel occlusion (S-E3; n = 1). E-S paradigms included superselective angiography followed by surgical clipping (E-S1; n = 2), Guglielmi detachable coil partial dome packing followed by delayed surgical clipping (E-S2; n = 2), proximal temporary vessel balloon occlusion followed by aneurysm clipping (E-S3; n = 2), and proximal permanent vessel occlusion followed by surgical aneurysm decompression for mass effect treatment (E-S4; n = 1).

RESULTS

Eleven aneurysms (92%) were completely eliminated. The remaining aneurysm was 90% obliterated and remained quiescent at the 34-month follow-up examination, despite presenting with subarachnoid hemorrhage. No patient experienced repeat bleeding (follow-up period, 23+/-28 mo). There were no deaths. One patient achieved a fair outcome (Glasgow Outcome Scale score of III); all other patients experienced excellent outcomes (Glasgow Outcome Scale score of I). In all cases, the aneurysm management paradigm chosen had a positive effect on definitive therapy.

CONCLUSION

Several factors can contribute to the complexity of intracranial aneurysms. Management strategies that combine operative and endovascular techniques in a complementary way, for the best possible outcomes for these patients, can be designed accordingly.

Giant aneurysms of the middle cerebral artery trifurcation treated with extracranial-intracranial arterial bypass and endovascular occlusion. Report of two cases

Giant middle cerebral artery (MCA) trifurcation aneurysms that cannot be excluded directly can be treated by flow inversion achieved by creation of an extracranial-intracranial bypass distal to the aneurysm, followed by occlusion of the parent vessel proximal to the aneurysm. As opposed to surgical occlusion, endovascular occlusion avoids dissection of the aneurysm area, and the site of occlusion can be chosen according to the flow distribution demonstrated on angiography performed during test occlusions. Two patients with giant aneurysms of the MCA trifurcation benefited from flow inversion treatment. Forty-eight hours after an MCA-superficial temporal artery bypass had been created, the M1 segment was occluded by inserting a coil in the first patient and the internal carotid artery was occluded with balloons in the second patient (there was no communicating artery in the latter case). Both occlusions were performed immediately after a clinical test of occlusion tolerance. The patients were clinically intact during the postoperative course. Follow-up angiography performed 11 and 4 months, respectively, after vessel occlusion showed that the aneurysm occlusion was stable.

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

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.

Temporary balloon protection as an adjunct to endosaccular coiling of wide-necked cerebral aneurysms: technical note

OBJECTIVE

We present an endovascular technique for treating wide-necked cerebral aneurysms using Guglielmi detachable coils (Target Therapeutics, Fremont, CA) and simultaneous temporary balloon protection. The temporary balloon serves as a mechanical external force to mold the microcoils away from the parent artery.

METHODS

Two illustrative cases of wide-necked cerebral aneurysms treated with Guglielmi detachable coils and a temporary balloon are presented. Emphasis is placed on the technical aspects of the approach, with several variations. The first case involves a left posterior cerebral artery aneurysm at the P1/P2 segment, and the second case involves a left paraclinoid internal carotid artery aneurysm. Both patients suffered from subarachnoid hemorrhage, but neither was a candidate for craniotomy. In each case, the coils, when used alone, protruded into the parent artery and were therefore removed. Then a temporary balloon was inflated for mechanical protection during coil deployment.

RESULTS

The use of simultaneous temporary balloon protection allowed more dense intra-aneurysmal coil packing, especially in the neck, without parent artery compromise, than did the use of Guglielmi detachable coils alone.

CONCLUSION

Endovascular treatment of wide-necked cerebral aneurysms can be facilitated by simultaneous temporary balloon protection.

Using transcranial duplex sonography for monitoring vessel patency during surgery for intracranial aneurysms

This article reports a method for reliable intraoperative monitoring of blood flow velocities in the basal cerebral arteries during clipping of intracerebral aneurysms. Transcranial color-coded duplex sonography provides practical integration of transcranial Doppler technology with real-time imaging capabilities through the intact human skull. With a computerized sonography system equipped with a 2.5-MHz probe in 50 healthy volunteers, the contralateral internal carotid artery, A1 and A2, as well as M1 and P1 vessels were identified and measured in most patients. In 13 patients undergoing dipping of intracranial aneurysms, the technique successfully imaged 12; it allowed definitive identification of vessels potentially threatened by clipping and not fully visible to the surgeon. Data were easily comparable to preoperative data. This noninvasive, repeatable neuroimaging technique provides useful intraoperative information about intracranial hemodynamics during dipping of intracranial aneurysms.