Unusual aneurysms of the distal internal carotid artery

Unusually Located Proximal Middle Cerebral Artery Saccular Aneurysm

Middle cerebral aneurysms constitute almost one-third of all anterior circulation aneurysms. Most of the saccular aneurysms originate from the arterial branching sites, but origins other than at the branching site are extremely rare. In this article, we are describing a unique M1 segment middle cerebral artery aneurysm which is not related with any branching site. Our literature search suggests that atherosclerotic changes in the arterial wall and local hemodynamic forces play an important role in the development of these types of aneurysm. Surgical management is not so unique in this type of aneurysm, but due to atherosclerotic parent arterial wall and thin-walled aneurysm sac, a neurosurgeon should be more cautious.

Long-term Follow-up of Blister Aneurysms of the Internal Carotid Artery

BACKGROUND:

Blister aneurysms of the internal carotid artery (ICA) are uncommon. There is a paucity of data on the long-term outcomes of patients.

OBJECTIVE:

To review our experience with the treatment of these lesions.

METHODS:

We retrospectively reviewed all aneurysms treated at our institution between 1994 and 2005. Relevant operative notes, radiology reports, and inpatient/outpatient records were reviewed.

RESULTS:

Seventeen patients (3 male, 14 female) with 18 blister aneurysms of the ICA were identified. The mean age was 44.6 years (range, 17–72; median, 42 years). Twelve patients (70.6%) presented with aneurysmal subarachnoid hemorrhage. The mean admission Glasgow Outcome Scale score was 4.3 (range, 2–5; median, 5). All patients were initially treated using microsurgical technique with direct clipping (n = 15; 83.3%) or clip-wrapping with Gore-Tex (n = 3, 16.7%). There were 4 cases of intraoperative rupture, all associated with attempted direct clipping; all 4 cases were successfully clipped. Two cases rebled post-treatment. Both rebleeding episodes were managed with endovascular stenting. Follow-up angiography was available for 14 patients and revealed a new aneurysm adjacent to the site of clipping in 1 patient and in-stent stenosis in 2. At the mean follow-up of 74.5 months (median, 73; range, 7–165), the mean Glasgow Outcome Scale score was 4.6 (range, 2–5; median, 5).

CONCLUSION:

Microsurgical treatment of blister aneurysms of the ICA results in excellent outcome. In the evolution of treating these friable aneurysms, we have modified our clip-wrapping technique and use this technique when direct clipping is not feasible.

Stent-assisted coil trapping in a manual internal carotid artery compression test for the treatment of a fusiform dissecting aneurysm

Internal carotid artery (ICA) trapping can be used for the treatment of giant intracranial aneurysms, blood blister-like aneurysms, and fusiform dissecting aneurysms. Fusiform dissecting aneurysms are challenging to treat surgically and endovascularly because of no definite neck and critical perforators. Surgical or endovascular trapping of the ICA with or without an extracranial-intracranial bypass has commonly been used as an effective method to treat these lesions, but balloon test occlusion (BTO) must be performed. Here, we report a case of a ruptured fusiform dissecting aneurysm of the distal ICA, which was successfully treated using an endovascular ICA trapping with a manual ICA compression test instead of BTO.

Endovascular treatment of blood blister-like aneurysms using multiple self-expanding stents

The surgical as well as endovascular treatment of blood-blister-like aneursysms (BBAs) is extremely difficult because of these pathological natures, such as small and the fragile necks. The optimal treatment of BBAs has remained uncertain. Stents are known to divert blood flow and induce thrombosis of intracranial aneurysms. We report 3 cases of successful obliteration of BBAs after multiple stents placement.

Surgical treatment of blood blister–like aneurysms of the supraclinoid internal carotid artery with extracranial–intracranial bypass and trapping

Object

Blood blister–like aneurysms (BBAs) arise from the supraclinoid internal carotid artery (ICA) at non-branching sites. These aneurysms are challenging to treat primarily with either surgical clip placement or endovascular therapy. The authors describe a series of 4 patients who presented with high-grade subarachnoid hemorrhage (SAH) due to a BBA, which was treated with an extracranial–intracranial (EC–IC) bypass followed by trapping of the aneurysm.

Methods

Four patients presented with SAH due to a BBA of the ICA. Three of these patients were treated with an endovascular procedure; following the vasospasm period, definitive treatment with EC–IC bypass followed by trapping of the aneurysmal parent vessel was performed.

Results

Two of the patients who were treated endovascularly suffered rebleeding prior to bypass and trapping. Three of the 4 patients had a good outcome (modified Rankin Scale Score 1 or 2), and 1 patient who suffered 2 episodes of rebleeding died.

Conclusions

Treatment of BBAs of the ICA remains difficult, particularly in the setting of high-grade SAH. Patients with this challenging condition often require multiple procedures and have a high incidence of rebleeding. Definitive treatment of these aneurysms consists of EC–IC bypass and surgical or endovascular trapping.

Endovascular treatment of blood blister-like aneurysms of the internal carotid artery

OBJECT

Because of its thin wall, an aneurysm arising from the posterior wall of the internal carotid artery (ICA), the so-called blood blister-like aneurysm (BBA), is difficult to manage surgically and is often associated with high morbidity and mortality rates. The authors treated these aneurysms endovascularly. In this paper, they present angiographic and clinical results obtained in patients with ICA BBAs treated endovascularly.

METHODS

In seven patients with ICA BBAs who presented with subarachnoid hemorrhage, a total number of 12 endovascular treatments were performed, including seven endosaccular coil embolizations (four conventional, two stent-assisted and one balloon-assisted procedure) in four patients and five endovascular ICA trapping procedures in five patients. Repeated endovascular treatments were undertaken in four patients. In two patients, the endovascular treatment was performed after failure of surgical treatment (one case of rebleeding after clip placement and one aneurysmal regrowth after wrapping). A balloon occlusion test (BOT) was performed in all patients prior to ICA trapping. All four patients treated by endosaccular coil embolization showed aneurysmal regrowth. Neither stents nor balloons helpfully prevented aneurysmal regrowth. Of these four patients, two experienced rebleeding. These two patients remained vegetative at the last follow-up examination. After the BOT, ICA trapping was performed with coils and balloons without complication in five patients; excellent outcomes were achieved in all cases but one in which the patient had been in poor neurological condition due to rebleeding after surgical clip therapy.

CONCLUSIONS

All ICA BBAs that were treated by endosaccular coil embolization exhibited regrowth of the aneurysm. Some of the lesions rebled. The majority of patients who underwent ICA trapping experienced excellent outcomes. Based on the authors' experiences, they suggest that ICA trapping including the lesion segment should be considered as a first option for definitive treatment if a BOT reveals satisfactory results. Regarding trapping methods, endovascular treatment may be preferred because of its convenience and safety.

Combined endovascular/neurosurgical therapy of blister-like distal internal carotid aneurysms

OBJECTIVE

To describe a novel therapeutic strategy for the treatment of "blister-like" aneurysms of the distal internal carotid artery (ICA). Direct surgical treatments of these fragile lesions have been associated with generally poor outcomes.

METHODS

Two consecutive patients presenting with acute subarachnoid hemorrhage from "blister-like" aneurysms were treated with preliminary balloon occlusion of the ICA, followed by surgical trapping of the ICA beyond the aneurysm.

RESULTS

The treatment resulted in complete thrombosis of both aneurysms with no clinical complications.

CONCLUSION

This combined endovascular-neurosurgical approach offers a controlled, safer alternative to primary surgical therapy of "blister-like" aneurysms.

Endovascular treatment of a "blister-like" aneurysm of the internal carotid artery

BACKGROUND

"Blister-like" aneurysms of the supraclinoid internal carotid artery have recently been recognized as having unique pathological and clinical features. Little is known regarding their optimal treatment modality.

METHODS

We report a case of a "blister-like" aneurysm of the internal carotid artery treated with Guglielmi detachable coil (GDC) embolization.

CASE REPORT

A 55-year-old man presented with a Hunt & Hess grade II subarachnoid hemorrhage. Computed tomography revealed diffuse subarachnoid blood. Cerebral angiography demonstrated a broad-based bulge on the medial wall of the right distal internal carotid artery. The patient was taken to the operating room and underwent a right pterional craniotomy and wrapping of this unclippable aneurysm. On postoperative day 11, he developed signs of vasospasm, and repeat angiography showed remarkable growth of the aneurysm. The aneurysm was believed to be amenable to endovascular therapy and was treated by GDC embolization. The patient recovered well and remained neurologically intact on follow-up examinations. Repeat cerebral angiography was performed three and nine months following his initial presentation and revealed a significant aneurysm neck remnant. This neck remnant was treated by repeat GDC embolization 13 months following his subarachnoid hemorrhage.

CONCLUSIONS

"Blister-like" aneurysms of the internal carotid artery are important to recognize and are difficult to manage using traditional surgical approaches. Early repeated cerebral angiography is indicated and, where appropriate, endovascular therapy should be considered in the management of these patients.