Cognitive and Cerebral Hemodynamic Effects of Endovascular Recanalization of Chronically Occluded Cervical Internal Carotid Artery: Single-Center Study and Review of the Literature

Endovascular recanalization for symptomatic chronic internal carotid artery occlusion: proposal of a modified angiographic classification and clinical outcomes

PURPOSE

To stratify angiographic images of chronic internal carotid artery occlusion (CICAO) into a newly modified angiographic classification, and identify suitable candidates for endovascular recanalization.

METHODS

This study included 51 consecutive patients with symptomatic CICAO who underwent endovascular recanalization at our institution. Patients' clinical information, angiographic findings, procedural results, and outcomes were recorded. We attempted to stratify all angiographic images into categories based on morphological occlusive patterns and distal internal carotid artery (ICA) lumen reconstitution on digital subtraction angiography (DSA).

RESULTS

Four types (I-IV) of CICAO were identified based on angiographic characteristics. We defined type I as having a tapered (IA) or blunt stump (IB) and distal ICA lumen reconstitution with collateral filling; type II as having no stump but with distal ICA lumen reconstitution; type III as having a tapered (IIIA) or blunt stump (IIIB) but no distal ICA lumen reconstitution; type IV as having no stump and no distal ICA lumen reconstitution. The rate of successful recanalization was 90.3 % for type I, 60.0 % for type II, 50.0 % for type III, 0 % for type IV, respectively (P = 0.002). The overall intraoperative complication rate was 11.8 %, and none of them led to severe neurological damage or death. The follow-up modified Rankin Scale (mRS) scores were significantly decreased in successfully revascularized patients, whilst there were no significant changes in the other failed patients.

CONCLUSION

For symptomatic CICAO, our newly modified angiographic classification may be comprehensive and useful in selecting suitable patients for recanalization and grading the difficulty of the procedures.

Influence of the integrity of circle of Willis on asymptomatic or mild patients with first diagnosed chronic internal carotid artery occlusion

BACKGROUND

In order to identify individuals with chronic internal carotid artery occlusion (CICAO), it is essential to understand the integrity of the circle of Willis (CoW). This understanding is important as it may determine the potential benefits of active medical and endovascular treatments.

PURPOSE

The objective of this study is to assess whether diminished integrity of the CoW can serve as a useful marker for identifying individuals with more severe impairment in cerebral blood perfusion and a higher incidence of cerebral infarction among asymptomatic or mildly affected patients with CICAO.

MATERIALS AND METHODS

We conducted a retrospective review of asymptomatic or mildly affected patients with newly diagnosed CICAO who did not receive reperfusion therapies. The categorization of patients into good or poor integrity groups was based on the assessment of CoW integrity using CTA. We evaluated the volume and value of prolonged time to peak (TTP) in both groups, as well as the occurrence of new cerebral infarctions. Our analysis involved multivariate regression and receiver operating characteristic (ROC) analysis.

RESULTS

Hemodynamic abnormalities characterized by prolonged TTP were observed in the affected side's blood supply region in all 38 patients. There was a notable difference in the volume and value of prolonged TTP between the two groups (P < 0.001). Correlation analyses based on CTP and CTA parameters revealed a negative relationship between CoW scores and both the abnormal volume (r = -0.624, P = 0.000) and value (r = -0.589, P = 0.000) of prolonged TTP. Upon multivariable adjustment, the independent predictors for new cerebral infarction and higher volume of prolonged TTP were solely the CoW status, with respective estimates of (b = 6.05; 95% confidence interval [CI]: 1.619, 22.619; P = 0.007) and (b = 35.486; 95% CI: 4.697, 268.088; P = 0.001).

CONCLUSION

Assessing the integrity of the CoW is crucial in evaluating abnormal perfusion in asymptomatic or mildly affected individuals who are newly diagnosed with CICAO and have not undergone reperfusion therapy.

Endovascular recanalization of chronically occluded internal carotid artery

Background

It is debated whether endovascular treatment is indicated for a symptomatic chronically occluded internal carotid artery (COICA).

Objective

To assess outcomes after endovascular treatment of COICA.

Methods

We performed a systematic search of three databases (PRISMA guidelines), including endovascular series of COICA. Outcomes were analyzed with random-effects models.

Results

We included 13 studies and 528 endovascularly treated patients with COICA. Successful recanalization was 72.6% (347/528, 95% CI 65.4% to 79.9%, I2=68.9%). Complications were 18% (88/516, 95% CI 12.1% to 23.8%, I2=65%), with 5% (25/480, 95% CI 2% to 7%, I2=0%) of permanent events, and 9% (43/516, 95% CI 6% to 13%, I2=34%) of thromboembolisms. Treatment-related mortality was 2% (11/516, 95% CI 0.5% to 2.6%, I2=0%). Shorter duration of the occlusion was associated with higher recanalization: 80% (11/516, 95% CI 54% to 89%, I2=0%), 63% (33/52, 95% CI 49% to 76%, I2=0%), and 51% (18/35, 95% CI to 37% to 88%, I2=40%) recanalization rates for 1, 3, and >3 months occlusions, respectively. Complications were 6% (3/50, 95% CI 3% to 21%, I2=0%), 14% (4/27, 95% CI 5% to 26%, I2=0%), and 25% (13/47, 95% CI 10% to 30%, I2=0%) for 1, 3, and >3 months occlusions, respectively. Patient aged <70 years presented higher revascularization rates (OR=3.1, 95% CI 1.2 to 10, I2=0%, p=0.05). Successful reperfusion was higher (OR=5.7, 95% CI 1.2 to 26, I2=60%, p=0.02) and complications were lower (OR=0.2, 95% CI 0.6 to 0.8, I2=0%, p=0.03) for lesions limited to the cervical internal carotid artery compared with the petrocavernous segment. Successful recanalization significantly lowered the rate of thromboembolisms (OR=0.2, 95% CI 0.8 to 0.6, I2=0%, p=0.01) and mortality (OR=0.5, 95% CI 0.1 to 0.9, I2=0%, p=0.04), compared with conservative treatment.

Conclusions

Endovascular treatment of COICA gives a 70% rate of successful recanalization, with 5% morbidity. Patients aged <70 years, lesions limited to the cervical internal carotid artery, and a shorter duration of the occlusion decreased the risk of complications. Successful recanalization of symptomatic lesions lowered by about 80% the likelihood of thromboembolisms, compared with medical management.