Ho, ho, ho! Gather around, my little elves, for a tale of high-tech holiday magic in the world of human in vivo liver surgery. In a workshop far, far away—also known as the operating room at Memorial Sloan Kettering Cancer Center—surgical Santas embarked on a quest to compare the mystical arts of rigid and nonrigid registration. They wielded two magical tools: the contact-based stylus, much like my trusty quill, and the noncontact Conoprobe, akin to Rudolph’s glowing nose, guiding the way without ever touching the ground.

These merry surgeons were on a mission to see which method would best navigate the snowy hills and valleys of the human liver, guiding them in their quest to remove unwelcome guests (also known as tumors). They gathered data from n=10 brave souls, venturing forth under the watchful eye of the Institutional Review Board.

With their sleighs loaded with data, they found that the stylus, much like a classic wooden toy, covered 24.6% ± 6.4% of the organ’s surface, while the Conoprobe, with its futuristic flair, covered a slightly lesser 19.6% ± 5.0%. When it came to the nonrigid registration methods—think of them as trying to fit a square present into a round stocking—the Conoprobe was a bit like a lumpy coal, performing slightly worse than the stylus by -1.05 mm and -1.42 mm, respectively.

But, fear not! When they combined their tools with a dash of Christmas magic (also known as tracking the vena cava with intraoperative ultrasound), both methods significantly outshone the old rigid registration method, much like LED lights compared to candles on a tree. The stylus improved by an average of 4.48 mm, and the Conoprobe by 3.66 mm.

So, in the end, my dear elves, the first-ever use of a Conoprobe in the sterile field of liver surgery was like opening a present on Christmas morning. While the nonrigid registration method, with its ability to adapt and flex, proved to be the superior guide through the liver’s nooks and crannies, the choice between the stylus and Conoprobe was akin to choosing between eggnog and hot cocoa—both delightful, with their own strengths and weaknesses. The true gift was in their combined power to improve navigation in liver surgery, a holiday miracle indeed!

Remember, my elves, in the world of surgery, as in the North Pole, innovation and teamwork light the way to a brighter future. Merry Christmas and a Happy New Year to all, and to all a good night!