Early detection of contrast-induced encephalopathy after mechanical thrombectomy using flat-detector CT: incidence, risk factors, and clinical implications.

PURPOSE

Contrast-induced encephalopathy (CIE) is a rare but increasingly recognized complication following therapeutic and diagnostic endovascular neurointerventions, including mechanical thrombectomy (MT). This study aimed to investigate the incidence, imaging characteristics, and risk factors of CIE, utilizing flat-detector (FD) CT for immediate post-interventional assessment.

METHODS

We retrospectively evaluated patients who underwent MT for acute ischemic stroke (AIS) between January 2020 and February 2023, who received FDCT directly after the intervention. CIE was diagnosed based on clinical criteria and radiological findings, confirmed with follow-up dual-energy (DE)-CT. Risk factors for CIE were analyzed using logistic regression, and associations with clinical outcomes (discharge mRS and mortality) were assessed.

RESULTS

CIE was identified in 16 patients of 339 (4.7%). Patients who developed CIE required a significantly higher number of device passes (median: 3 vs. 2, p = 0.033) and contrast volume exposure (200 mL vs. 110 mL, p = 0.017). Cervical ICA occlusion (p = 0.025) and intracranial stent angioplasty (p = 0.047) were frequent in the CIE group. Logistic regression confirmed the number of device passes as an independent predictor of CIE (OR: 1.51; 95% CI: 1.13-2.01; p = 0.005). No significant associations were found between CIE and unfavorable clinical outcomes (mRS > 3, p = 0.9) or mortality (p = 0.89).

CONCLUSION

FDCT allows for early detection of CIE-related radiological changes immediately after MT. Procedural complexity, including device passes, was identified as a risk factor. Identifying other risk factors require further investigations, due to the low incidence rate of detected CIE. These findings highlight the need for intensified monitoring for high-risk patients to mitigate the risk of CIE.