BrachyView is a novel in-body imaging system for real-time intraoperative prostate brachytherapy treatment planning, which monitors the position of low dose rate brachytherapy seeds using an array of high-resolution pixelated silicon detectors (Timepix). The detector array is also capable of performing in-body imaging of the prostate when used in conjunction with an external X-ray source. This study presents a quantitative analysis of the Timepix detector for use as a soft-tissue imaging plane by evaluating varying thicknesses of tissue-equivalent plastic incorporated into a medical prostate phantom. The feasibility of using BrachyView as a diagnostic tool is established by demonstrating the resolving power and high contrast obtainable with this configuration.