An Overview on the Considerations for the Planning of Nonclinical Necropsies for Medical Device Studies

Abstract

The terminal collection and histological processing of medical devices is an expensive, labor-, and material-intensive endeavor, which requires adequate experience, innovation, and preparation for success. It is also an exciting endeavor that continually challenges, intellectually engages, and improves the skills and knowledge of the pathologist. Awareness of the importance of the medical device pathologist's involvement, communication, and oversight throughout the development, implementation, and execution of a nonclinical assessment of a medical device is in the best interest of the test facility, the histopathology laboratory, the pathologist, the sponsor, and, ultimately, the patients. This article serves to present as a primer of key considerations for the approach and conduct of "nontoxicological" studies, defined as studies involving animal models of deployment or implantation of medical devices as well as surgical animal models.

Scientific and Regulatory Policy Committee Points to Consider for Medical Device Implant Site Evaluation in Nonclinical Studies

“…Implant study design must be tailored within the study scope to answer specific questions regarding pathology, safety (including biocompatibility), and sometimes functional performance (efficacy). 14,15…”

“…A pathologist, preferably one experienced with medical device studies, should provide insight and advice on likely biological responses, appropriate control material(s), sample endpoints and timepoints, tissue sampling methods, histology preparations, advanced tissue techniques, and appropriate qualitative and semi-quantitative evaluations. 14,16…”

“…The surgeon or interventionalist should inform the study pathologist about the general implantation procedure, and the pathologist should observe the implantation if not familiar with the medical device, implantation location, or implantation procedures. 14,19…”

“…The timing of sample collection, sampling procedures, and documentation requirements need to be carefully planned in advance according to the unique needs of the implant type and site of implantation. 14,23…”

“…The surgeon or interventionalist should inform the study pathologist about the general implantation procedure, and the pathologist should observe the implantation if not familiar with the medical device, implantation location, or implantation procedures. 14,19 b. The surgeon should indicate to the study pathologist whether secondary surgical medical devices (sutures, staples, clips, and/or glue) will remain in or near the medical device implantation site.…”