In a long-term study with lung transplant patients, researchers from Professor Jens Vogel-Claussen's working group at the BREATH site have developed an imaging method to predict a chronic rejection reaction that only occurs years after the transplant.
In 2022, 254 lung transplantations were performed in Germany. For long-term survival and quality of life after lung transplantation, detecting chronic lung allograft dysfunction (CLAD) as early as possible is essential to halt its progression. The occurrence of CLAD cannot yet be treated or cured causally, and about 50 percent of lung transplant patients are affected by it in the first five years after the operation.
Vogel-Claussen and his team have developed a method called phase-resolved functional (PREFUL) magnetic resonance imaging (MRI). It detects signal changes over the entire respiratory cycle (ventilation) through a change in the lung tissue's density and the cardiac cycle (perfusion) through changes in blood vessel density. It is a particularly patient-friendly imaging technique that does not require contrast agents, or breath holds. With this method, entire flow/volume curves can be determined, suitable for detecting heterogeneous regional differences in ventilation and perfusion. This is an essential advantage over spirometry (lung function test), which only measures global lung function and is currently used as a non-invasive method to detect CLAD after surgery.
Potential radiological biomarker for early detection
For the study, 106 adult patients were examined with the PREFUL MRI method a few months after double lung transplantation (baseline) and, on average, 2.5 years after the first MRI. CLAD and survival were assessed after 5.6 years. Of 24 patients, 19 died due to CLAD, and five were transplanted again. In the statistical comparison of the groups with and without CLAD, the potential of PREFUL-MRI ventilation parameters to predict subsequent graft loss was already evident about eight months after transplantation. Since spirometry could not predict mortality from CLAD or the need for retransplantation at this time, this reveals the additional clinical benefit of PREFUL-MRI. Future strategies to further improve early detection aim to conduct multicentre studies and integrate PREFUL data with other physiological and biological biomarkers and additional imaging to distinguish between the three CLAD subtypes, which differ markedly in prognosis.
This study is an important milestone on the way to the earliest possible individualised therapy management for lung transplant patients.
Vogel-Claussen J, Kaireit TF, Voskrebenzev A, Klimeš F, Glandorf J, Behrendt L, Gutberlet M, Korz C, Speth M, Welte T, Wacker F, Gottlieb J. Phase-resolved Functional Lung (PREFUL) MRI-derived Ventilation and Perfusion Parameters Predict Future Lung Transplant Loss. Radiology 2023 May;307(4):e221958. doi: 10.1148/radiol.221958.