Timing Of Occurrence As The Most Important Characteristic Improve The Predictive Performance Of CTP Spot Sign On Hematoma Expansion And Poor Outcomes

OBJECTIVESpot sign as a dynamic process of ongoing bleeding, the sensitivity of spot sign detection has been greatly increased from single-phase CTA to CT perfusion (CTP) which allows to track spot sign on the same slice in every phase of imaging acquisition. Our study aim to evaluate the significance of spot sign detected in different timing on CTP to HE and clinical outcome.METHODSWe retrospectively reviewed clinical and imaging data from71consecutive patients with spontaneous ICH who underwent a noncontrast CT (NCCT) followed by CTP acquisition at baseline within6h of onset. Logistic regression were performed to assess the risk factors of hematoma expansion and poor outcomes. Predictive performance of individual CTP spot sign characteristics were examined with receiver operating characteristic (ROC) analysis. RESULTSA total of71patients (50male,21female) who presented during the study period. ICH were found in the lobar location (8/71,11%) and the deep (supratentorial) location (63/71,89%). Multivariate analysis indicated the presence of spot sign (OR=9.749;95%CI,2.390-39.765; P=0.001) was independently associated with hematoma expansion (HE). ROC analysis indicated timing of detection was demonstrated of the greatest AUC (0.781;95%CI,0.603-0.958;P=0.014), the cutoff point was23.60seconds (sensitivity=0.64, specificity=0.88). Spot sign that presented before23.60seconds was defined as early detected spot sign, entering the analysis. Multivariable analysis determined that early detected spot sign was independent predictors of HE (OR=15.979;95%CI,3.791-67.346; P<0.001), and also the independent predictors of mortality (OR=41.862;95%CI,2.545-688.539; P=0.009). The early detected spot sign also demonstrated better performance on accuracy measures than spot sign.CONCLUSIONCTP spot sign is associated with HE and poor outcomes, wihch maintain a high rate of spot sign detection. Timing of spot sign detection is the most important spot sign characteristic.27.60seconds (with4seconds delay) after contrast injection is the optimal timing for spot sign detection. Early detected spot sign as a better biomarker, is more accurate in predicting HE and poor outcomes.