Human placenta in vascular neurosurgery training: a comprehensive review of laboratory models, possible exercises, and assessments for skills improvement.

Abstract

Introduction: Simulation is increasingly recognized as an important tool to enhance neurosurgical education. In this field, especially in neurovascular surgery, human placenta (hPl) is being recognized as a valuable training model because of its abundant availability, ethical acceptance, and analogous vasculature with other vessels of the human body. Nevertheless, although a rising body of literature is witnessing a renovated interest toward this "old" model, to date no comprehensive reviews on the topics are available. Main objective of this paper is to comprehensively review hPl use in neurovascular surgery training, focusing on model preparation, type of possible exercises along with assessment tools which can be used to check for trainees learning.

Evidence acquisition: A systematic review of the pertinent literature was performed, following PRISMA guidelines, searching the following key words in "title/abstract" fields in only English-written works: "placenta and neurosurgery." We focused on preclinical works concerning use of hPl models in neurovascular surgery training. We included studies published in the last 40 years, till December 31^st, 2023.

Evidence synthesis: A total of 950 scientific publications were initially screened, and 23 papers met the inclusion and exclusion criteria. In summary, the chorionic surface of hPl may be used as a neurovascular gym where different exercises can be performed. Placenta models can be produced with or without the use of intravascular dyes and or/pumping systems to resemble a beating-heart vascular system. The three main neurovascular surgical fields where hPl is being considered to be highly simulative are: 1) Sylvian fissure dissection; 2) aneurysm dissection and clipping; 3) bypass training. Considering the simulative purpose, face, content and construct validify of hPl model have been tested and verified by many authors, although still few data are available regarding transfer/predictive validity.

Conclusions: This systematic review highlighted the easiness of preparation and availability along with the strong didactical meaning that the use of hPl-based models may have in the field of neurovascular surgery training. In view of current progressive lowering of surgical vascular cases and increasing technical demand related to their management, further studies aimed to assess if this simulator could be able to produce a learning effect and improve performance with continued use are strongly needed.