Meta-Analysis
Copyright ©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Stem Cells. Jun 26, 2022; 14(6): 420-428
Published online Jun 26, 2022. doi: 10.4252/wjsc.v14.i6.420
Role of stem cells-based in facial nerve reanimation: A meta-analysis of histological and neurophysiological outcomes
Luca Ricciardi, Resi Pucci, Amedeo Piazza, Giorgio Lofrese, Alba Scerrati, Nicola Montemurro, Antonino Raco, Massimo Miscusi, Tamara Ius, Marco Zeppieri
Luca Ricciardi, Amedeo Piazza, Antonino Raco, Massimo Miscusi, Division of Neurosurgery, AOU Sant’Andrea, Department of NESMOS, Sapienza University, Rome 00189, Italy
Resi Pucci, Department of Oral and Maxillofacial Sciences, Sapienza University, Rome 00161, Italy
Giorgio Lofrese, Division of Neurosurgery, Ospedale Bufalini, Cesena 47521, Italy
Alba Scerrati, Department of Neurosurgery, Sant'Anna University Hospital, S. Anna University Hospital, Ferrara 44121, Italy
Alba Scerrati, Department of Morphology, Surgery and Experimental Medicine, University of Ferrara, Ferrara 44121, Italy
Nicola Montemurro, Department of Neurosurgery, Azienda Ospedaliera Universitaria Pisana, Pisa 56126, Italy
Tamara Ius, Neurosurgery Unit, Department of Neurosciences, Santa Maria della Misericordia University Hospital, Udine 33100, Italy
Marco Zeppieri, Department of Ophthalmology, University Hospital of Udine, Udine 33100, Italy
Author contributions: Ricciardi L wrote the outline, did the research, wrote the paper, and provided the final approval of the version of the article; Pucci R assisted in the research and writing of the manuscript; Piazza A and Miscusi M assisted in the editing and making critical revisions of the manuscript; Lofrese G assisted in data analysis and their discussion; Scerrati A assisted in the review process, papers selection and data collection; Montemurro N assisted in the data collection and analysis; Raco A assisted in the writing, editing and making critical revisions of the manuscript; Ius T assisted in the research and revisions of the manuscript; Zeppieri M assisted in the conception and design of the study, writing, outline, final approval of the version of the article to be published and completed the English and scientific editing.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 Checklist.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Marco Zeppieri, BSc, MD, PhD, Doctor, Department of Ophthalmology, University Hospital of Udine, p.le S. Maria della Misericordia 15, Udine 33100, Italy. markzeppieri@hotmail.com
Received: February 16, 2022
Peer-review started: February 16, 2022
First decision: April 19, 2022
Revised: April 21, 2022
Accepted: June 18, 2022
Article in press: June 18, 2022
Published online: June 26, 2022
Processing time: 127 Days and 22.6 Hours
Abstract
BACKGROUND

Treatments involving stem cell (SC) usage represent novel and potentially interesting alternatives in facial nerve reanimation. Current literature includes the use of SC in animal model studies to promote graft survival by enhancing nerve fiber growth, spreading, myelinization, in addition to limiting fibrotic degeneration after surgery. However, the effectiveness of the clinical use of SC in facial nerve reanimation has not been clarified yet.

AIM

To investigate the histological, neurophysiological, and functional outcomes in facial reanimation using SC, compared to autograft.

METHODS

Our study is a systematic review of the literature, consistently conducted according to the preferred reporting items for systematic reviews and meta-analyses statement guidelines. The review question was: In facial nerve reanimation on rats, has the use of stem cells revealed as effective when compared to autograft, in terms of histological, neurophysiological, and functional outcomes? Random-effect meta-analysis was conducted on histological and neurophysiological data from the included comparative studies.

RESULTS

After screening 148 manuscript, five papers were included in our study. 43 subjects were included in the SC group, while 40 in the autograft group. The meta-analysis showed no significative differences between the two groups in terms of myelin thickness [CI: -0.10 (-0.20, 0.00); I2 = 29%; P = 0.06], nerve fibers diameter [CI: 0.72 (-0.93, 3.36); I2 = 72%; P = 0.6], compound muscle action potential amplitude [CI: 1.59 (0.59, 3.77); I2 = 89%; P = 0.15] and latency [CI: 0.66 (-1.01, 2.32); I2 = 67%; P = 0.44]. The mean axonal diameter was higher in the autograft group [CI: 0.94 (0.60, 1.27); I2 = 0%; P ≤ 0.001].

CONCLUSION

The role of stem cells in facial reanimation is still relatively poorly studied, in animal models, and available results should not discourage their use in future studies on human subjects.

Keywords: Facial nerve; Palsy; Reanimation; Coaptation; Stem cells; Nerve fibers; Functional outcome

Core Tip: Our meta-analysis of studies comparing the use of autograft and stem cells for facial nerve reanimation in rats suggest that there appears to be no advantages in favor of stem cells, according to the evaluated histological and neurophysiological outcomes. Stem cell treatments have proven to be an interesting and viable option in numerous fields of surgery that have vast supporting scientific and clinically applicable literature. The role of stem cells in facial reanimation is still relatively new and poorly studied due to the liming nature and number of studies carried out exclusively in animal models.