Impact of lidocaine-induced mydriasis on postoperative outcomes in deep sclerectomy: a case report

Introduction: Non-penetrating deep sclerectomy (NPDS), introduced in 1989, is a glaucoma surgery technique that reduces intraocular pressure (IOP) by removing a deep scleral flap to facilitate aqueous humor drainage. Lidocaine, a local anesthetic, blocks sodium channels to reduce pain. It also affects pupil size and accommodation, particularly in light-colored irises, though the exact mechanisms are not well understood. Importance: This report highlights the potential impact of lidocaine on pupil dynamics and its role in altering the functionality of surgically created outflow pathways. Case presentation: A 60-year-old woman with advanced normal tension glaucoma underwent bilateral deep sclerectomy. The right eye surgery was successful, but the left eye developed an acute rise in IOP following the use of topical lidocaine. The mydriatic effect led to bleb dysfunction and eventual surgical failure, necessitating conversion to trabeculectomy. Clinical discussion: The transient mydriatic effect of lidocaine can compromise aqueous humor dynamics during the early postoperative period of deep sclerectomy. In eyes with light-colored irises, this effect may be more pronounced, increasing the risk of failure and IOP spikes. This case highlights the need for ophthalmologists to consider alternative anesthetics and to closely monitor postoperative pupil dynamics to avoid compromising surgical outcomes. Conclusion: Lidocaine-induced mydriasis can adversely affect the results of a deep sclerectomy. Awareness of this potential complication and careful selection of anesthetic agents are crucial to optimize outcomes in glaucoma surgery.