AUTHOR=Zhang Chao , Long Si-Yu , You Wen-dong , Xu Xu-xu , Gao Guo-Yi , Yang Xiao-Feng 

TITLE=The Value of the Correlation Coefficient Between the ICP Wave Amplitude and the Mean ICP Level (RAP) Combined With the Resistance to CSF Outflow (Rout) for Early Prediction of the Outcome Before Shunting in Posttraumatic Hydrocephalus

JOURNAL=Frontiers in Neurology

VOLUME=Volume 13 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2022.881568

DOI=10.3389/fneur.2022.881568

ISSN=1664-2295

ABSTRACT=Objective: To evaluate the value of the correlation coefficient between the ICP wave amplitude and the mean ICP level (RAP) and the resistance to CSF outflow (Rout) in predicting the outcome of Post-traumatic hydrocephalus（PTH）patients selected for shunting.
Materials and methods: As a training set, a total of 191 PTH patients treated with VP shunting were retrospectively analyzed to evaluate the potential pre-dictive value of Rout, collected from pre-therapeutic CSF infusion test, for a desirable Recovery Level (dRL) standing for the Modified Rankin Scale (mRS) of 0 to 2. Eventually, there were 70 PTH patients prospectively included as a vali-dation set to evaluate the value of Rout combined RAP as a predictor of dRL. We calculated Rout from a CSF infusion test and collected RAP during continuous external lumbar drainage (ELD). Maximum RAP (RAPmax) and its changes rela-tive to baseline (△RAPmax%) served as specific parameters of evaluation.	
Results: In the training set, Rout was proved to be a significant predictor of dRL to shunting, with the area under the curve (AUC) of 0.686 (P＜0.001) in receiv-er-operating characteristic (ROC) analysis. In the validation set, Rout alone did not present a significant value in the prediction of desirable Recovery Level (dRL ). △RAPmax% after 1st or 2nd day of ELD both showed significance in predicting of dRL to shunting with the AUC of 0.773 (P＜0.001) and 0.786 (P＜0.001), respectively. Significantly Rout increased the value of △RAPmax% in the prediction of dRL with the AUC of 0.879 (P＜0.001), combining with △RAPmax% after the 1st and 2nd day of ELD. RAPmax after the 1st and 2nd day of ELD showed remarkable predictive value for non-dRL (Level 3-6 in Modified Rankin Scale) with the AUC of 0.891 (P＜0.001) and 0.746 (P＜0.001).
Conclusions: Both RAP and Rout can predict desirable Recovery Level (dRL) to shunting in PTH patients in the early phases of treatment. RAP combined Rout is a better dRL predictor for a good outcome to shunting. These findings help the neurosurgeon predict the probability of dRL and facilitate the optimization of the individual treatment plan in the event of ineffective or unessential shunting.