Comparison of Manual and Semiautomatic Volume of Interest Drawing For the Analysis of Spinal Cord Myelin Pet Imaging

Abstract

This study aims to compare the manual and semiautomatic method for volume of interest (VOI) drawing of Positron Emission Tomography (PET) images with Carbon-11 labeled Pittsburgh Compound B ([ 11 C]PIB) of Cervical Spinal Cord (SC). Studies using PET images of spinal cord are scarce, probably, due to the difficulty associated with reduced dimensions and respiratory movement of this region, therefore, more suitable method of drawing the VOIs in this region still needs further evaluation. [ 11 C]PIB PET images and T1-weighted MRI were acquired from 10 healthy volunteers in a simultaneous hybrid PET/MR system. The VOIs were placed using: 1) manually, using iso-contour tool, and 2) semi-automatically, using ellipse and rectangle shape tool, slice by slice, oriented by vertebral levels (C1/C2-C4) and drawing in the axial and sagittal plane. The statistical analyses were performed by GraphPad Prism 8 software, using one way ANOVA. The results are presented in SUV (Standardized Uptake Value) at C1/C2, C3 and C4 levels. There were no statistical differences between the four VOI drawing strategies. Manual and semi-automatic drawing showed similar results, allowing the choice by a personal analyst preference.