Direct clip obliteration of a ruptured giant aneurysm of the posterior communicating artery: case report

Microsurgical Approach for True Posterior Communicating Artery Aneurysms: Literature Review and Illustrative Case

True posterior communicating artery (PCoA) aneurysms are rare. Although true PCoA aneurysms have been reported to be located close to the internal carotid artery, at the middle part of PCoA, or close to the posterior cerebral artery; the best surgical approach to treat true PCoA aneurysms in each location remains unclear. We conducted a literature review using data from PubMed. Data on demographics, location, and projecting direction of the aneurysm, surgical approach, and surgical complications were collected. A total of 47 true PCoA aneurysms were included. Twenty-nine aneurysms originated from the proximal portion, 10 from the middle portion, and 6 from the distal portion; there were two giant aneurysms. The ipsilateral pterional approach was used for 37 true PCoA aneurysms (27 in proximal portion, 8 in middle portion, and 2 in distal portion of PCoA). The anterior temporal approach was used for two distal-portion aneurysms and one giant aneurysm. The anterior subtemporal approach was used for one distal-portion aneurysm. The subtemporal approach was used for two middle-portion aneurysms and one giant aneurysm. The contralateral pterional approach was used for two proximal-portion and one distal-portion aneurysms. Although most true PCoA aneurysms can be treated by the pterional approach, other means such as anterior temporal and subtemporal approaches can be applicable for aneurysms in the middle and distal portions of the PCoA or giant aneurysms. Surgeons should select an appropriate approach for each aneurysm while considering the advantages and disadvantages of each technique.

Thrombosed Giant "True" Posterior Communicating Artery Aneurysm Treated by Trapping and Thrombectomy

Giant “true” posterior communicating artery (PCOM) aneurysms are rare and the best surgical treatment for them is unclear. We present a case of 85-year-old woman with this type of lesion, 35 mm in diameter, successfully treated by trapping and thrombectomy via pterional approach without complications. There were no perforating arteries originating from the aneurysmal wall. The patient had an uneventful postoperative course. The key for successful treatment for such lesions is preservation of perforators, as trapping may result in ischemic complications. However, our case indicates that trapping and thrombectomy might have relatively low risks for development of such complications, supposing that the thrombosis within the giant “true” PCOM aneurysm induced spontaneous obliteration of perforators, arising from the aneurysmal dome, and that collateral flow from the posterior cerebral artery already compensated the corresponding territories.

Successful flow reduction surgery for a ruptured true posterior communicating artery aneurysm caused by the common carotid artery ligation for epistaxis

Background:

Carotid artery occlusion can lead to the development of rare true posterior communicating artery (PCoA) aneurysms because of hemodynamic stress on the PCoA. Surgical treatment of these lesions is challenging.

Case Description:

The authors report a case of a true PCoA aneurysm that developed and ruptured 37 years after ligation of the ipsilateral common carotid artery for epistaxis. The lesion was successfully treated with clipping of the distal M1 segment of the middle cerebral artery (MCA) after the occipital artery-radial artery free graft-MCA bypass, which led to extreme reduction in collateral flow through the PCoA. A cortical branch, located just proximal to the obliteration site, functioned as a sufficient flow outlet. The aneurysm shrank, and the patient has been doing well without any symptoms for 5 years after surgery.

Conclusions:

M1 obliteration combined with high-flow extra-intracranial bypass might be a promising option for a true PCoA aneurysm, and therapeutic design that leaves a sufficient flow outlet on the M1 is mandatory to avoid unexpected occlusion of the M1 and its perforators.

Diagnostic pitfalls associated with a large true posterior communicating artery aneurysm: a case report

True posterior communicating artery (PCoA) aneurysm is an aneurysm that originates from the PCoA, and large or giant true PCoA aneurysms are rare. We report a case of a large true PCoA aneurysm successfully clipped after anterior clinoidectomy and discuss the diagnostic pitfalls associated with this rare clinical entity.

Surgical management of giant posterior communicating artery aneurysms

BACKGROUND

Giant posterior communicating artery (PCoA) aneurysms (> 25 mm) are rare lesions associated with a poor prognosis and high rates of morbidity and mortality.

OBJECTIVE

To review the clinical results of giant PCoA aneurysms surgically treated at our institution, focusing on operative nuances.

METHODS

All cases of giant PCoA aneurysms treated surgically at our institution were identified from a prospectively maintained patient database. Patient demographic factors, medical comorbidities, rupture status, neurological presentation, clinical outcomes, and surgical records were critically reviewed.

RESULTS

From 1989 to 2010, 11 patients (10 women) underwent surgical clipping of giant PCoA aneurysms. Presenting signs and symptoms included cranial nerve palsies, diminished mental status, headache, visual changes, and seizures. Five aneurysms were ruptured on admission. All aneurysms were clipped primarily except 1, which was treated by parent artery sacrifice and extracranial-to-intracranial bypass after intraoperative aneurysm rupture. Perioperative morbidity and mortality rates were 36% (4 of 11) and 18.3% (2 of 11), respectively. Excellent or good clinical outcomes, defined as modified Rankin Scale scores ≤ 2, were achieved in 86% (5 of 6) of patients available for long-term clinical follow-up (mean, 12.5 ± 13.6 months).

CONCLUSION

Giant PCoA aneurysms are rare vascular lesions that may present with a variety of neurological signs and symptoms. These lesions can be successfully managed surgically with satisfactory morbidity and mortality rates. To the best of our knowledge, this is the largest surgical series of giant PCoA aneurysms published to date.

Microsurgical experience with keyhole operations on intracranial aneurysms

BACKGROUND

We report our experience with keyhole approaches as favorable treatments for various intracranial aneurysms including multiple aneurysms and giant aneurysms.

METHODS

According to the different locations of 105 aneurysms harbored in 100 patients, different keyhole approaches were designed elaborately, among which a supraorbital keyhole approach was used in 91 cases, a pterional keyhole approach in 5 cases, a subtemporal keyhole approach in 3 cases, a retromastoid keyhole approach in 2 cases, and a unifrontal interhemispheric keyhole approach in 1 case.

RESULTS

Among those 105 aneurysms, 99 were clipped successfully, including 4 that were resected after clipping. One mini-aneurysm was wrapped. The other aneurysms were trapped, including 1 VA aneurysm, 1 giant ICA aneurysm, 1 giant PCoA aneurysm, and 2 giant aneurysms in the PCAs (P2-P3 segment). Multiple aneurysms in 5 cases were treated in 1 surgical session, including 3 cases via unilateral approaches and 2 cases via bilateral approaches. There were no severe keyhole approach-related complications in this present series.

CONCLUSION

The keyhole approaches, based on improvements in diagnostic imaging, advanced surgical instruments, and microsurgical skills, are effective and ideal craniotomy techniques in the hands of experienced neurosurgeons for the treatment of intracranial aneurysms, including multiple and giant aneurysms, in patients without diffuse SAH, severe cerebral vasospasm, and severe brain edema or brain swelling.

Incomplete oculomotor nerve palsy caused by an unruptured internal carotid-anterior choroidal artery aneurysm--case report--

A 59-year-old woman visited our institute with the chief complaint of dizziness which persisted whenever she tried to focus on objects. She had not experienced apparent double vision and had no history of intracranial bleeding. Neurological examination revealed no abnormality except for exotropia at the mid-position and at upper gaze. Cerebral angiography revealed that the intracranial portion of the left internal carotid artery ran more horizontally and also identified an unruptured left internal carotid-anterior choroidal artery (IC-AChA) aneurysm of 3.0 mm diameter. The aneurysm at the origin of the AChA was confirmed during surgery. The proximal lateral wall of the aneurysm was in contact with the oculomotor nerve. This contact was released after complete obliteration of the aneurysm. The exotropia resolved 3 months later. Oculomotor nerve palsy usually indicates the presence of internal carotid-posterior communicating artery (IC-PcomA) aneurysm. Since sacrifice of the AChA will result in severe neurological deficits, accurate neuroimaging information is needed prior to the operation. Conventional angiography and/or three-dimensional computed tomography angiography should be performed to ascertain whether the aneurysm is an IC-PcomA or IC-AChA aneurysm, even if some neurosurgeons insist that conventional angiography is not always needed before surgery for an unruptured aneurysm.

Factors influencing the outcome after the operative treatment of cerebral aneurysms of anterior circulation

BACKGROUND

The influence of various factors on the outcome after the operative occlusion of the cerebral aneurysm was to be defined through the retrospective study on 111 surgically treated patients with aneurysm of anterior cerebral circulation.

METHODS

Preoperative clinical condition was graded from 0 to V, according to Hunt & Hess. Postoperative outcome, defined as good or bad according to modified Glasgow Outcome Scale, was correlated in homogenous experimental groups with the following factors: gender, age, aneurysmal size, preoperative interval, nimodipine therapy, experience of surgical team and existence of chronic vascular diseases.

RESULTS

Surgical outcome was good in 74.4% of males and 71.4% of females (p > 0.05); in 83.3% of patients with and 41.2% of patients without chronic diseases (p < 0.01); in 71.4% of patients underwent early, 83.3% of ones underwent postponed and 85% of those underwent late surgery (p > 0.05); in 81.5% of patients treated by nimodipine and in 41.7% of those untreated by the same drug (p < 0.01); in 78.9% of patients operated by the experienced surgical team and in 40% of those operated by less experienced surgical team (p < 0.01). In patients with both good and bad outcome, the mean age was 50.6 and 47.6 years (p > 0.05), and the mean aneurysmal size was 12.3 mm and 13.3 mm, respectively (p > 0.05). Before rupture, the mean size for aneurysms on the bifurcation of the middle cerebral artery was 14.3 mm, and for posterior communicating artery aneurysms only 9.7 mm (p < 0.05).

CONCLUSION

Surgical outcome was significantly influenced by the existence of chronic diseases, nimodipine therapy and experience of surgical team, whereas gender, age, timing for surgery and aneurysmal size were not of significant influence.

Subarachnoid hemorrhage as a result of fungal aneurysm at the posterior communicating artery associated with occlusion of the internal carotid artery: case report

BACKGROUND

Fungal or "true" mycotic aneurysms of the intracranial circulation are very rare. Rupture of a fungal aneurysm is fatal in almost 100% of cases.

CASE DESCRIPTION

We report a 65-year-old woman with a ruptured fungal aneurysm on the posterior communicating artery associated with occlusion of the internal carotid artery. She had a past history of gastric malignant lymphoma and subsequent granulocytopenia. She survived after surgical treatment including trapping of the aneurysm and a superficial temporal artery-to-middle cerebral artery bypass.

CONCLUSION

Improved immune response at the time of the onset of subarachnoid hemorrhage, as well as additional vasoreconstructive surgery, may have contributed to favorable outcome after surgical treatment.

Bypass combined with embolization via a venous graft in a patient with a giant aneurysm in the posterior communicating artery and bilateral idiopathic occlusion of the internal carotid artery in the neck

The authors describe the case of a patient with a symptomatic giant aneurysm of the posterior communicating artery (PCoA) associated with bilateral idiopathic occlusion of the internal carotid artery (ICA). The presence of severe tortuosity of the vertebral arteries (VAs), both at their origin from the subclavian artery and at the level of the third segment, impeded navigation of the catheter for embolization of the aneurysm with Guglielmi detachable coils (GDCs). A direct surgical approach was considered to be a high-risk procedure because of the bilateral occlusion of the ICAs and the size of the aneurysm. The following therapeutic strategy was therefore adopted: 1) balloon occlusion test of the left VA; 2) vertebro-vertebral bypass with saphenous vein graft to provide a pathway for subsequent embolization; 3) ICA-left middle cerebral artery bypass to ensure blood flow in the event that embolization resulted in closure of the PCoA; and 4) GDC embolization of the aneurysm via the posterior circulation graft to ensure complete exclusion of the lesion from the arterial circulation and preservation of the PCoA. At 3-month follow-up review the patient did not present with any neurological deficits; at 1-year control examination, magnetic resonance (MR) imaging and MR angiography both confirmed complete exclusion of the aneurysm and patency of the two bypasses.

Evaluation and endovascular treatment of juxtaorbital vascular anomalies

The evaluation of juxtaorbital anomalies with routine imaging, including CT and MR imaging, usually is insufficient for endovascular therapy planning. Cerebral angiography remains crucial to define detail necessary for endovascular therapy. This article provides an overview of the authors' approach and the endovascular therapies available to treat these lesions.

Saccular aneurysm induction by elastase digestion of the arterial wall: a new animal model

OBJECTIVE

To develop a rabbit aneurysm model that is more realistic in gross appearance and histological features than previous models and to enable the development of a larger animal model.

METHODS

Ten rabbits received porcine pancreatic elastase, five at the right common carotid artery bifurcation and five others at the right superior thyroid artery origin. One control animal received collagenase and another received papaverine, each at the right superior thyroid artery origin. The agents were topically delivered to the arterial adventitia with a microsyringe after surgical exposure of the targeted arteries. The arteries were monitored for aneurysm growth with a video camera for up to 3 hours and were then removed and processed for histology.

RESULTS

Saccular aneurysms developed in one of five animals after elastase application at the carotid bifurcation and in all five animals receiving elastase at the superior thyroid artery origin. Among the six aneurysms, recurrent minor hemorrhages occurred in four, thrombosis of the aneurysm sac in three, and rupture causing severe bleeding in one. Histological sections revealed thin-walled aneurysms composed only of collagen fibers and some cellular elements. No saccular dilation resulted from papaverine application. Collagenase application resulted in a hemorrhagic-thrombotic lesion in the arterial wall but no aneurysm formation.

CONCLUSION

Arterial saccular aneurysms were induced in rabbits by topical application of elastase with an easy and efficient method. These aneurysms are histologically similar to natural aneurysms, and their arterial nature renders them more authentic than those of surgical models. This aneurysm model may serve as a foundation for further aneurysm research.