A transformation in how surgeons learn, practice, develop and refine procedures is happening, and its epicenter is the Patrick C. Walsh Discovery and Learning Laboratory, part of the new Surgical Learning and Innovation Center of Excellence (SLICE).

“Patrick Walsh transformed a major operation in urology and revolutionized the treatment of prostate cancer,” says Jakurski Family Director of the Brady, Mohamad “Mo” Allaf, M.D. “He worked tirelessly on discovery – finding ways to control dangerous bleeding, uncovering significant, previously unseen and unknown nerve structures that are critical for erection, and preserving the sphincter responsible for urinary control – and then refining his operation over the next decades.

This laboratory, named in Dr. Walsh’s honor, is the new home of transformative surgical innovation and learning at the Brady. Here, as part of SLICE, we will incubate future discovery, nurture urologic surgeons-in-training, and help experienced surgeons learn new procedures and techniques.”

SLICE is the brainchild of Ahmed Ghazi, M.D., Director of Minimally Invasive and Robotic Surgery at the Brady. The seeds were planted years ago, during his surgical training in laparoscopy and robotic surgery. It struck him at the time that “there was no ideal way to train a surgeon. We were training on the go – basically, building the plane as we flew.”

Wouldn’t it be better, he thought, if new surgeons could develop proficiency in procedures before they performed them on patients? Ghazi explored this idea using a machine simulator; these are effective for student pilots, who spend many hours doing simulation flights. But surgery is tactile.

There is blood, tissue, fat, muscle, fascia, and bone. A glorified video game, he realized – no matter how high-tech and realistic the experience – is just not the same.

“Surgery Bleeds”

Then he tried making surgical training models using 3D printing. This, too, was not the solution. “Surgery bleeds. I knew from the beginning that whatever models we made, they needed to bleed.” So, 3D printing could not make the organs – but it could be used to make molds for organs that did look and feel just like the real thing. The key turned out to be the use of hydrogel, a water-based, semi-solid polymer scaffold that can absorb fluids and maintain its shape.

Eventually, Ghazi had his first prototype, a small block of hydrogel with a vessel in the middle. The “blood” was not red: “It was actually black ink because we couldn’t find anything else. But it looked very realistic.” When he tested it, the replica tissue bled. And it kept bleeding – so much that Ghazi had to close the fake wound. He couldn’t walk away from it. “I thought, ‘This needs to stop’” – and this, he says, was an “aha!” moment. The hydrogel models were so life-like that they were compelling. Next, with a biomedical engineer, Ghazi developed and patented a detailed library of all the different textures that, layered together, make up a realistic human anatomy, and of different organs: kidney, liver, colon, prostate, bladder.

Then he got a master’s degree in education. He has developed curricula for different sets of learners: medical students; surgical residents; practicing surgeons who want to learn a new technique or procedure; and practicing surgeons who want to plan and practice a specific operation for complicated cases, such as a large kidney tumor. The models can be generalized for training or made patient-specific, using the patient’s own imaging and biopsy results.

What Makes This Different?

“There are several surgical training and simulation centers across the U.S.,” says Ghazi. “What makes ours different? The ability to combine an innovative and patented methodology to custom-build very realistic, bleeding models for training.” To maintain consistency and quality, the surgical models are built in-house. “We custom-build the model to the learner’s level, and we customize the learning platform based on who the learner is. Our educational approach is also essential: we innovate not only to design the models, but also to design the actual curriculum for training.”

For example, learning at the Walsh Laboratory can happen over months. “That’s really geared for people adopting a very new approach they’ve never done before,” Ghazi explains. Or it can be done in a “master class” environment, “three or four days of hands-on training that enables an already proficient surgeon to adopt a new technique,” and this, too, is customized.

“Before anybody starts our programs, we evaluate them. We customize the training based on their starting level, and at the end we want them to get to the expert level.”

What’s an expert? Ghazi has determined that, as well. “We got 50 expert urologists to perform surgery using our models,” and then by tracking the surgeons’ eye movements, data on technique from the machine itself, and from sensors placed within the models, “we were able to quantify what it means to be an expert surgeon. To get surgeons to expert level, we use proficiency-based progression. It’s not like you do this ten times and then you’re done, but you continue to do it until you reach a certain level.”

The Brady will be constructing a facility for SLICE on the Johns Hopkins Medicine campus that Ghazi is customizing for optimal surgical training. The space will enable operations to be transmitted in ultra high-definition 3D, as well as telesurgery and remote training using a secure 5G network. “From here, I will be able to take control of a surgical robot or machine across the country on the West Coast, and teach somebody based there.” SLICE has two Da Vinci surgical robots for training purposes, and “we are in negotiations to get more,” Ghazi says.

There will also be equipment and models for teaching endoscopic surgery, laparoscopic surgery, and open surgery. “Our major source of revenue is philanthropy,” Ghazi notes, with additional funding through several societies, NIH grants, and industry-sponsored grants. Those who come to Hopkins for training or a master class pay a registration fee.

Planning For Very Difficult Operations

Word of mouth about SLICE is already spreading among patients as well as surgeons. One patient “has a very difficult tumor in her kidney,” Ghazi explains. “She spoke with several urologists at other centers. The tumor is very deep in the kidney, surrounded by blood vessels.” Several doctors told her the entire kidney needed to be removed. The patient, a scientist, “didn’t think a tumor that small – about 3 cm – should require removal of the entire kidney." The patient contacted Ghazi and asked if he could save her kidney. His answer: “I don’t know. What I need to do is make a model of your kidney (with a hydrogel tumor embedded in the precise location of the real one) and practice on it.” Ghazi did, and he found a way to do a partial nephrectomy. “The patient is coming from New York and will watch as I perform a practice operation in virtual reality. We will meet in the metaverse, and we will virtually go inside the tumor. We’ll be virtually standing in the kidney, and I will show her, ‘that’s your tumor, that’s your blood vessel.’”

Ghazi has had similar sessions with other patients, and the response has been overwhelmingly positive: One patient said, “If you end up sacrificing the kidney, I am assured that you did everything in your means to save it.’ Going to these lengths gives the patient extra peace of mind.”

Improving Prostatectomy

With MRI images, Ghazi can create an exact replica of the prostate in all its complexity. “This is truly customizable surgery: there’s no way this surgery will be the exact same for each patient,” because each prostate is slightly different; the structures surrounding it may be different, and each tumor is unique. “We aim to perfect the surgery,” he says.

“I believe that 10 years from now we will not be removing the entire prostate; we will remove part of the prostate.” If cancer is near the nerves, does this mean just cut as much tissue as possible? “What if we say, ‘Let’s practice and see?’ That is the trajectory where we are going in prostate cancer.”

Preserving Organs Near the Bladder

In patients who undergo surgery to remove the bladder, “we’re teaching new techniques for organ preservation” – of the prostate in men, and the uterus in women. “These are more difficult procedures that require extra training, and that’s why fewer people do them,” says Ghazi. He is working with Brady urologist Armine Smith, M.D., with funding from a patient, to develop models to perfect these techniques.

Surgeons, says Ghazi, “can never get complacent. The technology is changing ever so rapidly.” Everyone needs continuing education. “If our vision for SLICE is realized, Johns Hopkins will become a destination for urologists, cardiologists, interventional radiologists, gastroenterologists – we have models and courses for multiple specialties,” and for entire surgical teams, as well.