Prognostic Value of Apparent Diffusion Coefficient for Mechanical Thrombectomy in Patients with Acute Posterior Ischemic Stroke

Background: This study investigates the prognostic value of the apparent diffusion coefficient (ADC) in magnetic resonance imaging for patients with acute posterior circulation stroke (PCS) undergoing endovascular therapy (EVT).

Methods: A retrospective analysis was conducted of patients with acute PCS from January 2017 to December 2021, confirmed by diffusion-weighted imaging (DWI)-ADC within 24 hours of onset. Patients were categorized based on their 3-month modified Rankin Scale score after EVT. Data on the National Institutes of Health Stroke Scale at admission, ADC value, and 3-month modified Rankin Scale score were collected. Multivariable logistic regression analyzed the impact of various factors on ADC values. The receiver operating characteristic curve assessed predictive indices.

Results: Among 94 patients, 47 had a good prognosis and 47 had a poor prognosis. Univariate analysis showed that factors significantly associated with a good prognosis included lower National Institutes of Health Stroke Scale at admission, higher ADC values, smaller infarct areas, unilateral infarction, basilar artery occlusion, lower pons-midbrain-thalamus scores, intravenous thrombolysis, intra-arterial thrombolysis, and fewer perioperative complications (P < 0.05). Multivariable logistic regression identified high ADC values (P = 0.002) and unilateral infarction (P = 0.017) as independent predictive factors for prognosis. An ADC value >549 × 10^-6 mm²/second was associated with a higher rate of good prognosis. Combining ADC values with unilateral infarction resulted in the highest area under the curve and Youden Index of 0.766, with sensitivity and specificity of 89.36% and 87.23%, respectively (P < 0.05).

Conclusions: High ADC values and unilateral infarction are independent predictive factors for the prognosis of patients with PCS after EVT. Combining these factors provides the highest predictive accuracy, aiding in clinical decision making for PCS treatment.