Giant internal carotid artery aneurysm case series

Yan et al., retrospectively reviewed 126 consecutive patients with 128 large intracranial aneurysm or giant intracranial aneurysms which were treated with different endovascular techniques between January 2014 and February 2017 in the Beijing Tiantan Hospital and Beijing Tsinghua Changgeng Hospital. They then compared clinical and angiographic outcomes, as well as the technical events rate among different treatment modalities.

In this study, complete occlusion at last follow-up was achieved in 65.6%, 90.5% and 72.0% of aneurysms in Stent assisted coiling (SAC), Parent artery occlusion (PAO) and Pipeline embolization device (PED) group (P=0.119). Both at 6 months (OR=1.81, P=0.396) and last angiographic follow-up (OR=3.64, P=0.123), PAO was not superior to PED regarding complete occlusion rate. Retreatment rate was statistically different among 3 groups (P<0.001) and the rate was highest in the SAC group (21.9%). The rates of hemorrhagic events and ischemic events were not significantly different among 3 groups (P=0.581). However, mass effect exacerbation was more frequently seen in SAC group (24.4% vs 7.7% and 3.3%, P=0.004). Major complication rate was higher in PAO group compared with PED group, however, the difference did not reach statistical difference (19.2% vs 16.4%, OR=1.21, P=0.763). The rate of technical events was statistically different in three groups (p=0.0437) and these problems occurred more often during the employment of PED (18.0%).

For large and giant internal carotid artery aneurysm, the outcome for endovascular treatment remains poor, even after the introduction of Pipeline embolization device ¹⁾.

Sheen et al., reviewed the records of 68 patients with 69 aneurysms, including large and giant intradural ICA aneurysms, treated using microsurgical techniques from January 2008 to December 2014. They used Adenosine induced cardiac standstill or retrograde suction decompression for some aneurysm clipping cases and performed bypass surgery if needed.

Fifty-eight large and giant ICA aneurysms (84%) were treated with direct clipping, including 6 aneurysms (9%) clipped using adenosine-induced cardiac standstill and 10 aneurysms (14%) clipped using suction decompression. Eleven unclippable aneurysms (16%) were trapped with extra intracranial bypass surgery. Good or excellent results (modified Rankin Scale scores 0-2) were obtained in 47 patients with unruptured aneurysms (92%) and in 14 patients with ruptured aneurysms (82%) at the 6-month follow-up. Of 17 patients with visual disturbances before treatment, 11 (65%) had improved vision after surgical treatment. A remnant sac was found in 20 cases (29%) on digital subtraction angiography performed immediately postoperatively. At the median follow-up of 22 months, they encountered 3 recurrent aneurysm cases (5%) among the 58 aneurysms that were followed up.

The study demonstrated that microsurgical treatment of large and giant intradural ICA aneurysms remains competitive to flow diverter treatment, if the surgeon is prepared to perform multifarious surgical methods, including adenosine administration, retrograde suction decompression, and bypass vascular anastomosis ²⁾.

Between January 1995 and January 2015, occlusion of the ICA was considered in 146 patients with large or giant ICA aneurysms. Ninety-six patients (66%) passed the angiographic test occlusion, and, in 88 of these 96 patients (92%), the ICA was permanently occluded. In 11 of 88 patients with angiographic tolerance, ICA occlusion was performed with the patient under general anesthesia without clinical testing.

There was 1 hypoperfusion infarction after hypovolemic shock from a large retroperitoneal hematoma (complication rate 1.1% [95% CI, 1%-6.8%]). The mean imaging and clinical follow-up was 35 months (median 18 months; range, 3-180 months). On the latest MR imaging, 87 of 88 aneurysms (99%) were completely occluded and 61 of 80 aneurysms (76%) were decreased in size or completely obliterated. Of 62 patients who presented with cranial nerve dysfunction by mass effect of the aneurysm, 30 (48%) were cured, 25 (40%) improved, 6 (10%) were unchanged, and 1 patient (2%) was hemiplegic after a complication.

ICA occlusion for large and giant aneurysms after angiographic test occlusion was safe and effective. Two-thirds of eligible patients passed the angiographic test. Most aneurysms shrunk, and most cranial nerve dysfunctions were cured or improved ³⁾.

In the report of Li et al. all the patients were divided into two groups: Group A: patients who underwent parent artery occlusion, and Group B: patients who underwent stent-assisted coil embolization. Follow-up outcomes were evaluated using the modified Rankin Scale (mRS).

After 12 months of follow-up, the favorable outcome (mRS: 0-2) had no statistical significance in both groups (p = 1.00). Patients in group A had greater ischemia compared with patients in group B, but the difference did not reach statistical significance (p = 0.421). In group B, patients had a higher rate of partial occlusion (p = 0.255) and recurrence (10% vs. 0%; p = 0.586).

Stent-assisted coiling may not be superior to parent artery occlusion in selected patients after short-term follow-up. Parent artery occlusion is a simple, safe and effective treatment for large/giant internal carotid aneurysms.

Four cases of giant or large paraclinoid aneurysms of the internal carotid artery successfully trapped after assessing blood flow using a flowmeter are presented. In all cases, the initial plan for clipping was changed to aneurysm trapping due to various reasons. The collateral blood flow was assessed using the flowmetry test, the original procedure of measuring volumetric blood flow in the middle cerebral artery using an ultrasonic flowmeter. We analyze the reasons for clipping refusal, the procedure of measuring blood flow, treatment outcomes, and catamnestic data. The risks of reconstructive surgeries involving the internal carotid artery are discussed and the literature data are analyzed. Conclusions. Ultrasonic flowmetry is a simple and safe method for intraoperative control over blood circulation, which may play the key role in complicated surgical cases ⁴⁾.

Rathore et al. retrospectively analyzed 27 patients with giant and complex ICA aneurysms who underwent carotid artery ligation between January 2001 and December 2010. Clinical presentation included headache, vision loss and diplopia. There were 19 patients with cavernous aneurysm, 5 supraclinoid, 1 ophthalmic, 1 petrous segment and 1 cervical segment aneurysm located extracranially. All demonstrated good cross-circulation. Selverstone clamp was used for gradual occlusion of the ICA over 72 h under closed observation in the intensive care unit.

Six patients developed hemiparesis in the postoperative period. Improvement occurred in one patient over two to three weeks while the remaining five patients had residual hemiparesis. One patient developed malignant MCA infarct for which decompressive craniectomy had to be done. There was no mortality in the present series.

Gradual monitored occlusion and ICA ligation may be a simple, safe alternative procedure to clipping in surgically inaccessible and complex aneurysms, especially for surgeons with limited experience. Cross circulation study is an absolute requisite for carotid ligation ⁵⁾.

In 16 patients with 17 large or giant (11-45 mm) unruptured ICA aneurysms presenting with dysfunction of cranial nerves (CN) II, III, IV, or VI, selective coil occlusion was performed. From a cohort of 39 patients with ICA aneurysms treated with ICA occlusion and long-term follow-up, we selected 31 patients with aneurysms presenting with cranial nerve dysfunction. Clinical recovery at follow-up from oculomotor dysfunction and visual symptoms was compared for both treatment modalities.

Of 17 aneurysms treated with selective coiling, symptoms of cranial nerve dysfunction resolved in 3, improved in 10, and remained unchanged in 4. In 9 of 17 patients, additional coiling during follow-up was required. Of 31 aneurysms treated with carotid artery occlusion, cranial nerve dysfunction resolved in 19, improved in 9, and remained unchanged in 3. These differences were not significant. There were no complications of treatment.

Recovery of ICA aneurysm-induced cranial nerve dysfunction occurs in most patients, both after ICA occlusion and after selective coiling. In patients who cannot tolerate ICA occlusion, selective aneurysmal occlusion with coils is a valuable alternative ⁶⁾.