Sir,

Intracameral lidocaine is often used to augment topical anesthesia during ocular surgery. This is a safe and effective method of anesthesia that eliminates discomfort caused by tissue manipulation and thus improves patient cooperation. Although rare, complications can occur. We describe a case of a rare complication with intracameral lidocaine.

Case report

We report a patient who underwent peripheral iridectomy under topical anaesthesia, augmented by intracameral lidocaine 1%. He had vitrectomy for retinal detachment years ago, and vision was 20/70. He underwent a recent repeat vitrectomy with secondary anterior chamber intraocular lens inserted for dislocation of posterior chamber intraocular lens. The surgery was uneventful, but when the dressing was removed an hour later, he noted complete loss of vision. Vision was perception of light with the presence of a relative afferent pupillary defect (APD). Anterior and posterior segment was normal, with no evidence of disc swelling or cherry red spot. Carotid examination revealed no bruit. He reported gradual return of vision over 4 h. Within 20 h, vision improved to counting fingers at 3 m with resolution of APD. Two weeks later, vision recovered to 20/30 with no residual defects.

Comment

Intracameral lidocaine (1%) can result in transient visual loss.1, 2 The recovery period here was similar to the case of Lincoff et al,3 where inadvertent intraocular injection of lidocaine showed improvement in retinal function 4 h later and recovery in 16 h. This is rare but can occur especially in cases of communication with the posterior segment, for example, ruptured posterior capsule and aphakia, where anaesthesia can diffuse readily into the vitreous cavity coming into direct contact with the retina and optic nerve. Visual recovery is complete with no apparent functional damage. Electrophysiological studies in animals injected with intraocular lidocaine4 show b-waves demonstrated a decrease in the amplitude and an increase in the implicit time. Electroretinogram responses recovered within 24 h.

In the absence of a definite anaesthesia history, only after adequate investigation to rule out vascular or neurological complications, one can attribute amaurosis to intracameral lidocaine.

This case illustrates that intracameral lidocaine 1% is safe to use to augment topical anaesthesia, even when posterior capsule is not intact. The surgeon should be aware that transient amaurosis may occur. Patients can be reassured that it is reversible, although this may take up to several hours to days. In patients with a deficient capsule, or one-eyed patients, other alternatives such as subtenon or peribulbar anaesthesia can be considered.