A new diagnostic tool developed at Rambam Health Care Campus enables accurate diagnosis of infected vascular grafts. The implications: Early detection, easy and effective planning of treatment and elimination of unnecessary surgical exploration that may lead to graft infection.

A new study conducted at Rambam Health Care Campus decreases the need for invasive surgical procedures and saves lives and limbs. The PET-CT device integrates two diagnostic methods (PET and CT) performed simultaneously (fusion). This technology, employed today for diagnosis of cancer and metastases, has been harnessed by the team of researchers at Rambam to develop a new diagnostic tool that provides accurate diagnosis of infected vascular grafts.

The study demonstrating the advantage of this combined technology was conducted by Dr. Zohar Keidar, Deputy Director of the Department of Nuclear Medicine in collaboration with the Department of Vascular Surgery & Transplantation directed by Prof. Aaron Hoffman and his deputy Dr. Samy Nitecki and with Dr. Ahuva Engel, Director of the Medical Imaging Department.

Dr. Nitecki explains that graft infection is a severe, late and most unwelcome complication following vascular reconstructive surgery. Vascular graft infection may occur despite sterile conditions and meticulous handling of the inserted device in the operation room. The incidence of vascular graft infection ranges between 0.5-6%. Depending on the anatomical location, this serious post-surgical complication harbors a poor prognosis and may result in life or limb loss in more than 50% of the patients.

Up till now, infected grafts have been identified using standard imaging and laboratory methods, but results have usually been insufficient. A CT scan, the first line of investigation, enabled an accurate anatomic diagnosis but lacked  a functional-metabolic diagnosis, namely a definite answer as to the actual existence of an inflammatory process, due to some normal post-operative changes. On the other hand a PET scan provided an accurate diagnosis regarding the existence of an inflammatory process but lacked anatomical landmarks and topographical localization. Thus an invasive surgical exploration had to be performed just in order verify or rule out the presence of a graft infection. This surgical procedure and the exposure of the graft may cause an infection, pain and/or complications.

The new method is based on injecting a marked sugar component (FDG). This component is drawn to highly metabolic activity such as an infection. During the study, the fusion of PET and CT scans indicated the existence of an infection and confirmed its location most accurately. Precision was very high: It was possible to differentiate between an infected graft and an infection of the surrounding tissue. Moreover, it allowed differentiation of an infected graft between two adjacent ones.

Dr. Nitecki has recently been invited to the faculty of the VEITH Symposium, the world’s largest vascular convention, where he presented this innovative method and the results obtained.