O15: DISRUPTION OF THE BLOOD-SPINAL CORD BARRIER PREDICTS PERMANENT PARAPLEGIA AFTER THORACOABDOMINAL AORTIC ANEURYSM REPAIR

Abstract Introduction Paraplegia post-thoracoabdominal aortic aneurysm (TAAA) repair remains both a devastating and poorly understood complication. We related temporal changes in cellular protein composition of cerebrospinal fluid (CSF) to neurological outcomes after TAAA gain mechanistic insights driving paraplegia. Method Patients undergoing (open or endovascular) with CSF drain were prospectively recruited between 2016-2018. was collected pre-operatively 24-hourly until removal. Daily examinations performed by blinded neurologists the study. cell content characterised flow cytometry proteome analysed tandem-mass-tag proteomics. An in-vivo rat model modified using 15 minutes occlusion produce consistent Rats neuro-behaviourally histologically. Result from 52 patients (age: 70.27+/-11.4; 66% male; open (n=9), endovascular (n=43)). 12 developed paraplegia whom 5 remained permanently-paraplegic. Demographics comparable paraplegics, those who recovered without post-op neurology. Permanent associated significant infiltration CD45+ leucocytes (P<0.0001). Levels ADVS-1 >3-fold higher permanent-paraplegics versus (P=0.0008). >15ng/ml predicted permanent 100% specificity. Pre-treatment inhibition significantly improved walking (<0.001) increased astrocytic staining lateral corticospinal, reticulospinal rubrospinal tracts controls (P=0.03, 0.04, 0.04 respectively). Conclusion is shedding parenchymal cord into blood/spinal-cord barrier disruption leading oedema/leucocyte infiltration. led neurobehavioural histological improvements offering translational hope for this Take-home message novel biomarker where accurate biomarkers have proven challenging but more importantly it has therapeutic target genuine potential.