Back to Journals » Clinical Ophthalmology » Volume 14

Outcomes and Adverse Events of Sub-Tenon’s Anesthesia with the Use of a Flexible Cannula in 35,850 Refractive Lens Exchange/Cataract Procedures

Authors Lerch D, Venter JA, James AM, Pelouskova M, Collins BM, Schallhorn SC

Received 16 October 2019

Accepted for publication 11 December 2019

Published 31 January 2020 Volume 2020:14 Pages 307—315


Checked for plagiarism Yes

Review by Single anonymous peer review

Peer reviewer comments 2

Editor who approved publication: Dr Scott Fraser

Dagobert Lerch, 1, 2 Jan A Venter, 2 Anca M James, 1, 2 Martina Pelouskova, 2 Barrie M Collins, 2 Steven C Schallhorn 2–4

1Montanamed Ltd., Sankt Gallen, Switzerland; 2Optical Express, Glasgow, UK; 3University of California, Department of Ophthalmology, San Francisco, CA, USA; 4Carl Zeiss Meditec, Dublin, CA, USA

Correspondence: Dagobert Lerch
Montanamed Ltd, Ozartstraße 6, Leipzig D-04107, Germany
Tel +49 152 53447537

Purpose: To describe our technique of sub-Tenon’s anesthesia and report adverse events and patient comfort.
Setting: Optical Express, United Kingdom.
Design: Retrospective case series.
Methods: The outcomes of 35,850 intraocular procedures (phacoemulsification and implantation of an intraocular lens) were retrospectively reviewed and the incidence of adverse events related to sub-Tenon’s anesthesia was calculated. On the first postoperative day, patients were asked to complete a questionnaire enquiring about their comfort during and after the procedure. The anesthetic solution consisted of a combination of Lidocaine and Hyaluronidase, which was administered into sub-Tenon’s space with a single-use sterile polyurethane 22G x 1” (0.9 x 25 mm) cannula. Mild conscious sedation (midazolam) was used during anesthetic and surgical procedure.
Results: No significant adverse events that would affect the posterior segment of the eye or result in vision loss were recorded. Subconjunctival haemorrhage related to sub-Tenon’s anesthesia was noted in 4.3% of eyes. Five minutes after the administration of sub-Tenon’s block, 80.6% of eyes had no chemosis, 14.8% had chemosis that affected only 1 quadrant of the eye and 4.5% of eyes had chemosis affecting 2 or more quadrants of the eye. Other adverse events included 14 cases of cyst/granuloma formation in the area of sub-Tenon’s incision and 7 eyes required suturing of the conjunctival cut. Of all patients, 93.2% experienced no or only mild discomfort during or after surgical procedure.
Conclusion: Sub-Tenon’s anesthesia with the use of a flexible cannula is a safe option for ophthalmic anesthesia. No sight-threatening adverse events occurred.

Keywords: sub-Tenon’s anesthesia, flexible cannula, refractive lens exchange, adverse events

Creative Commons License This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.

Download Article [PDF]  View Full Text [HTML][Machine readable]