Why is unable to find ROI during the bright focus procedure?

The inability to find the Region of Interest (ROI) during the bright focus procedure can occur due to inadequate illumination or improper alignment of the optical system, which can affect the clarity of the target area. Additionally, if the tissue structure is not well-defined or if there are artifacts present, it can hinder accurate identification. Technical issues with the imaging equipment or operator experience may also contribute to difficulties in locating the ROI.