Systematic Reviews
Copyright ©The Author(s) 2025. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Exp Med. Sep 20, 2025; 15(3): 106429
Published online Sep 20, 2025. doi: 10.5493/wjem.v15.i3.106429
Systematic review and risk factor analysis of post-vitrectomy silicone oil migration to the central nervous system
Lucy Wing Wong, Wai Yan Lam, Sunny Chi Lik Au
Lucy Wing Wong, Division of Undergraduate, Chinese University of Hong Kong, Hong Kong 999077, China
Wai Yan Lam, Department of Ophthalmology, Grantham Hospital, Hong Kong 999077, China
Sunny Chi Lik Au, Department of Ophthalmology, Tung Wah Eastern Hospital, Hong Kong 999077, China
Co-first authors: Lucy Wing Wong and Wai Yan Lam.
Author contributions: Wong LW drafted the manuscript; Wong LW and Lam WY analyzed the data; Wong LW and Au SCL acquired the data; Lam WY revised the manuscript; Au SCL designed the research study; all authors had full access to the data, contributed to the study, read and approved the final version for publication.
Conflict-of-interest statement: All authors have disclosed no conflicts of interest. This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
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: Sunny Chi Lik Au, Chief Physician, Research Fellow, Department of Ophthalmology, Tung Wah Eastern Hospital, 9/F, MO Office, Lo Ka Chow Memorial Ophthalmic Centre, No. 19 Eastern Hospital Road, Causeway Bay, Hong Kong 999077, China. kilihcua@gmail.com
Received: February 26, 2025
Revised: March 20, 2025
Accepted: April 7, 2025
Published online: September 20, 2025
Processing time: 167 Days and 18.2 Hours
Abstract
BACKGROUND

Silicone oil (SiO) migration to the central nervous system (CNS) is a rare complication of SiO tamponade after vitreo-retinal surgeries, it could masquerade hemorrhage on computed tomography neuro-imaging. Only limited cases were reported in the literature, certain intra-operative and post-operative ocular risk factors might contribute to the different extend of SiO migration in the CNS.

AIM

To study the risk factors for cerebral ventricular migration (CVM) on top of visual pathway migration (VPM).

METHODS

Conforming to the preferred reporting items for systematic reviews and meta-analyses guidelines, literature searches on PubMed, MEDLINE, EMBASE were performed on June 1, 2024. Publications on SiO migration to CNS were included in this review. Non-English articles, and studies without neuro-imaging of the CNS were excluded. Patient demographics, SiO filled eyes' ocular characteristics and vitrectomy surgical details were extracted from included studies in this review. VPM and CVM were assigned as group 1 and group 2 respectively. Fisher's exact tests, Mann-Whitney U tests and binary logistic regression were performed.

RESULTS

Total 68 articles were obtained after searches, 48 publications were included for analysis. Total 54 SiO filled eyes were analyzed. Post-vitrectomy intraocular pressure (IOP) was found to be significant in both Mann-Whitney U test (P = 0.047) and binary logistic regression (P = 0.012). Diabetic was found to be significant in binary logistic regression (P = 0.037), but at borderline risk for CVM in Fisher's exact test (P = 0.05). Other significant factors include longer SiO tamponade time (P = 0.002 in Fisher's exact test) and visual acuity (P = 0.011 in binary logistic regression). Optic nerve atrophy or disc cupping (P = 1.00, P = 0.790) and congenital optic disc anomalies (P = 0.424) were all with P > 0.05.

CONCLUSION

SiO migration to CNS is rare with limited case reports only. Our analysis of the existing literature demonstrated higher post-vitrectomy IOP was associated with CVM, followed by patients’ diabetic status, longer SiO tamponade time and visual acuity. Optic nerve atrophy, disc cupping and congenital optic disc anomalies were not associated. Modifiable risk factors of post-vitrectomy IOP and SiO tamponade time should be closely monitored by vitreo-retinal surgeons. Lower IOP target post-vitrectomy and earlier SiO removal surgeries should be arranged.

Keywords: Vitrectomy; Silicone oils; Central nervous system; Systematic review; Ophthalmology; Retina; Cerebral ventricles; Lateral ventricles; Optic nerve; Visual pathway

Core Tip: It is interesting to note that silicone oil (SiO) migration to optic chiasm causes visual field loss or deteriorated visual acuity in the contralateral eye. And timely treatment can reverse such complications. Cerebral ventricular migration (CVM) of SiO are largely asymptomatic, commonly being diagnosed on imaging for other medical issues. Most treatments are mainly conservative, especially as when it is asymptomatic. However, CVM was occasionally misrecognized as intraventricular haemorrhage. Healthcare providers should pay attention to this rare but possible event as this misidentification could potentially delay emergency treatments in stroke patients.