"Several years ago I made some comments about these images that were insensitive to the seriousness of what the images revealed. Soon thereafter, I removed those images and comments, again several years ago," Wolf said in a statement on his campaign website.
"For them to be published in a much more public context now, by a political adversary who would rather declare war on doctors than answer serious questions that Kansans have, is truly sad. However, my mistakes are my own and I take full responsibility for them."
Medical professionals questioned whether Wolf was allowed to publish such images to social media, but the candidate insists that he had not violated anyone's privacy.
"My training as a diagnostic radiologist included the critical component of studying medical images published both in textbooks and online. I have myself authored and published educational material that teaches medical imaging to medical students and doctors," he said in the statement. "Of the thousands of medical images I have published I have taken care to maintain patient privacy."
Wolf criticized his opponent, Roberts, for attacking his character.
"It’s sad. Pat Roberts has not been able to identify a single issue on which he thinks I am wrong and so he’s doing things the Washington way: character assassination," Wolf said. "Kansans should know that I will not be intimidated by their bullying."