Introduction: In the field of research on imaging techniques prior to and after kidney transplantation (KTX), guidelines mainly provide recommendations based on “low level of evidence” and “expert opinions”. New research and publications on imaging techniques for the evaluation of transplant recipients seem to have stagnated, limiting the development of adequate evidence-based guidelines.Therefore, we evaluated the yearly publication and citation rates in the field of pre- and post-KTX imaging.
Materials and Methods: We evaluated all original publications and reviews issued in the field of clinical medicine and medical imaging between 1996 and 2016. We searched the Web of Science (WoS) database, collecting the number of publications and citations. Four imaging groups were included: ultrasonography (US), magnetic resonance imaging (MRI), computed tomography (CT) and nuclear medicine imaging (NM). Next, we evaluated the number of imaging publications and citations in both clinical and imaging journals.
Results and Discussion: We identified 31,001 KTX publications in clinical journals, 5.6% of which focused on imaging, and 216,661 publications in imaging journals, 0.3% of which focused on KTX. The share of imaging publications in clinical journals increased from 5.6% to 6.5% in 21 years (US 2.4% to 2.7%, MRI 0.9% to 0.9%, CT 0.5% to 2.5%, NM 0.3% to 0.4%), while the share of KTX publications in imaging journals decreased from 0.5% to 0.3% (US 0.7% to 0.5%, MRI 0.3% to 0.2%, CT 0.3% to 0.2%, NM 0.7% to 0.2%). The average h-index for publications in clinical journals for 1996 was 0.2 for publications on imaging and KTX and 3.3 for non-imaging publications, showing an annual increase rate of respectively 50.2% and 16.7% up until 2016. In imaging journals, the average h-index was 0.2 for publications on imaging and KTX and 4.5 for all publications on imaging techniques, with a yearly increase rate of respectively 59.4% and 16.4%.
Conclusion: While knowledge and techniques in the field of medical imaging have steadily increased over the past years, their share in the total number of KTX publications remains low. Meanwhile, there is a need for comprehensive evidence-based KTX guidelines for imaging and transplantation. With these outcomes, we advocate for an increased focus on this topic and subsequently more research funding. New investments are required to conduct high-quality research projects and to expand the knowledge for comprehensive evidence-based KTX guidelines.