Introduction: Mechanical thrombectomies (MT) have been one of the central management strategies for selected acute ischemic stroke patients. While data supports the efficacy of MTs in patients between the ages of 18-65, MT data is limited in patients older than 80. 
 
 Method: Retrospective analysis was conducted on patients from January 2018 to December 2019. The patients were subdivided by age into an octogenarian group (OG; ages 80 or above) and a non-octogenarian group (NOG; ages 18-79). Primary outcomes were measured with NIHSS (NIH stroke scale) scores difference between 24 hours post-MT and at arrival. Additional outcome measures included post-MT thrombolysis in cerebral infarction (TICI) scores 2B/3, mortality, and symptomatic intracranial hemorrhage (sICH) within 24 hours. Hypertension, diabetes, atrial fibrillation, prior TIA/CVA history, alcohol and smoking history, location of the occlusion, IV tPA administration, ASPECT scores (pre and post thrombectomy), door to groin puncture time, and door to recanalization time were analyzed. A two-sample t-test was used for statistical analysis. 
 
 Result: 156 NOG and 46 OG patients were included in this study. The median age of NOG and OG groups were 63 and 86, respectively. OG patients were more likely to be female (69.6%) than NOG patients (females=48.73%). Hypertension was the single most common risk factor in both groups, with 69.62% in NOG and 78.26% in OG. Statistically significant improvement in NIHSS score (mean ± SD [median]) after MT was seen in both OG (from 14.0. ± 6.8[14] to 12.5 ± 8.8[10]) (p<0.0001) and NOG (16.2 ± 6.1[16]) to 12.0 ± 8.1[11.5]) (p=0.0078). However, the degree of NIHSS improvement of OG (mean ± SD = -4.24 ± 6.22) was larger compared to those of NOG (-1.44 ± 8.79) (p=0.017). All-cause mortality rates of OG (39.3%) was higher than NOG (19%). There were no differences in symptomatic ICH rates, TICI 2b/3 rates, IV tPA administration rates, median door to groin puncture (NOG: 1:26 vs. OG: 1:17) and median door to recanalization (NOG: 2:17 vs. OG: 2:15) between the two groups. MCA occlusion was the most common presentation in both groups (NOG: 68.4% v OG: 87.0%). 
 
 Discussion & Conclusion: Octogenarians showed a better degree of NIHSS improvement in 24 hours post-MT which may indicate that MT can be an effective treatment strategy in acute strokes in all age groups. However, the post-MT mortality rate was higher in octogenarians, thus warranting additional investigation.

43rd ESNR Annual Meeting