Minimally invasive first
Updated: Sep 3, 2021
Vascular surgeons in Münster focus on innovation and in-house research. This has a positive impact on complex procedures as well as on patients and staff.
The St. Franziskus Hospital in Münster, Germany, plays a very important role in regional patient care while also enjoying an international reputation for innovation. Martin Austermann, MD, is developing minimally invasive methods to treat patients more gently, safely, and effectively.
The team around Martin Austermann, since March 2020 head of the clinic for vascular surgery, has a challenging task on its agenda: a 78-year-old-female patient requires treatment for a pathological dilation of the aorta in the thoracic and abdominal region (a thoracoabdominal aortic aneurysm). The physicians must prevent the aorta from rupturing, which would lead to a life-threatening hemorrhage. Planning the minimally invasive treatment involves inserting a y-shaped stent prosthesis into the aorta.
This special prosthesis, custom-made for the patient, has side arms designed to ensure that the organs of the abdominal cavity and the kidneys continue to be supplied with blood.
The vascular surgeons then extend these side arms into the target vessels of the kidneys and abdominal organs using so-called bridging stents. The aorta which was at risk to rupture is now protected by the prosthesis. All this is possible through small incisions in both groins and the left armpit, allowing to access the vessels for the endovascular treatment. There is no need to open up the patient’s chest and abdominal cavity, which would have caused her considerable strain for an uncertain outcome. Because it is performed through the arteries, this treatment is called endovascular aneurysm repair (EVAR). Even so, it is a complex treatment for which four hours have been scheduled for this patient. Procedures like this require repeated angiograms, in other words X-ray images of the vessels, to be taken intraoperatively to monitor every step. This would lead to a high level of applied X-ray dose. But the team and its patients now benefit from the latest generation angiography equipment. As Austermann reports, the experience gathered with the device since it went into service in August 2020 is persuasive.
St. Franziskus Hospital has a long tradition of introducing important new innovations. In the 24 years since its foundation in 1996, the Department of Vascular Surgery under the leadership of Professor Giovanni Torsello, MD, has gained a reputation for being one of the most innovative centers around. Even in the early days, the team was especially interested in minimally invasive therapies. As a result, the department has been the first in the world to implant a number of new vascular prostheses, including some for complex aortic surgery. Another pioneering moment was in 2003, when the St. Franziskus Hospital commissioned Germany’s first hybrid operating room (OR) – the first to enable high quality intraoperative imaging. This took the hospital closer to its aim of minimizing open surgery and as often as possible treating patients on a minimally invasive basis. Immediate visualization of the blood flow also helps avoid costly and stressful revision surgery.
Cooperation as basis for development
Even when they were building the first hybrid OR in 2003 there was close collaboration with the specialists from Siemens Healthineers. The vascular surgeons got a wide range of support. “More than other companies, Siemens Healthineers understood the needs of surgeons,” explains Torsello. Among other things, the floor-mounted angiography system is hygienic because it allows the free circulation of air through the ventilation system in the ceiling.
Cooperation with Siemens Healthineers was also key to efforts to build a second hybrid operating room at the St. Franziskus Hospital, and continues with another premiere: the installation of the latest angiography system, the ARTIS icono. The approach of treating complex disorders of the entire aorta, the neck vessels, and also strokes and critical ischemia of the legs as non-invasively as possible is being taken consistently further by the new chief Austermann and his team. They aspire to be involved early on in the development of advances in medical technology. This was also the case for the new angiography system. Already at the prototype stage the vascular surgeons worked with the technology experts to pave the way for the integration of fusion imaging. The software automatically detects and marks vessel walls and branching vessels in the CT image created prior to surgery. It’s now possible to merge the CT image, the marked anatomical structures, and the current intraoperative angiograms; in other words they can be overlaid, or as Austermann puts it, “married.” The doctors can keep a permanent eye on whether the catheter or stent is in the right position.
Even though the latest generation angiography system hasn’t been in use at St. Franziskus Hospital for long, the whole surgical team can clearly feel how much workflows have changed. Another development Austermann finds very exciting apart from fusion imaging – which saves so much time, radiation exposure and contrast agent – is a software called OPTIQ. This allows a required image quality to be set in advance, which an algorithm then keeps constant during a performed procedure step, optimizing the dose of radiation. Another improvement in workflow has been possible thanks to so-called Case Flows. This allows situations occurring during a procedure to be defined in advance so that the angiography system can take up the appropriate positions as standard during surgery. The vascular surgeons have already defined a number of different Case Flows and expect this to facilitate their work considerably.
Last, but not least, the fully motorized C-arm enables images of 2.10 meters longitudinally and imaging of the foot area. Despite this, the equipment takes up so little room that it easily fits into the limited space available in the hybrid room.
Research for clinical application
To gather as much evidence as possible as the basis for developing patient care, the vascular surgeons are looking into many different methods in their own studies. To this end the Institute of Vascular Research has been established at the St. Franziskus Hospital. It covers a broad spectrum, with 24 studies currently under way. One example is bridging stents. They are approved for the treatment of arterial occlusive diseases, but also help when it comes to connecting branched stents to kidney vessels. Now the institute is investigating a proprietary method to see whether bridging stents can withstand the specific stresses around the kidney arteries in the long term.
Another key area of research is imaging with carbon dioxide, particularly important for patients with high blood pressure and diabetes. Since the kidney function of these people is impaired, conventional contrast agents can increase the risk of potential unwanted side-effects. Now a registry study under Austermann’s leadership will take a thorough look at the safety of CO2 imaging.
The Department of Vascular Surgery looks after around 3,000 patients a year. To further improve their treatment, the doctors screen conference presentations and publications for the tools of the future. But the vascular specialists in Münster also want to share their insights with established and up-and-coming colleagues, and with nursing staff. They now have Vascupedia, a platform that provides structured information and dialog options for registered users from all over the world.