Effects of Miosis on Anterior Chamber Structure in Glaucoma Implant Surgery

Abstract

We investigated changes in anterior chamber (AC) structure after miosis in phakic eyes and pseudophakic eyes with glaucoma. In this prospective study, patients scheduled for glaucoma implant surgery were examined using anterior segment optical coherence tomography before and after miosis. Four AC parameters (AC angle, peripheral anterior chamber (PAC) depth, central anterior chamber (CAC) depth, and AC area) were analyzed before and after miosis, and then compared between phakic and pseudophakic eyes. Twenty-nine phakic eyes and 36 pseudophakic eyes were enrolled. The AC angle widened after miosis in both the phakia and pseudophakia groups (p = 0.019 and p < 0.001, respectively). In the phakia group, CAC depth (p < 0.001) and AC area (p = 0.02) were significantly reduced after miosis, and the reductions in PAC depth, CAC depth, and AC area were significantly greater than in the pseudophakia group (all p < 0.05). Twenty-five patients (86.2%) in the phakia group and 17 (47.2%) in the pseudophakia group had reduced CAC depth (p = 0.004). Although miosis increased the AC angle in both groups, AC depth decreased in most phakic eyes and a substantial number of pseudophakic eyes. Preoperative miosis before glaucoma implant surgery may interfere with implant tube placement distant from the cornea during insertion into the AC.

A Guide to the Repair of Traumatic Cyclodialysis Clefts: Medical, Laser, and Surgical Treatment

“…Miotics should not be used in the treatment of cyclodialysis due to its opposing effects to atropine. Miotics can also widen the cleft by increasing tension on the iris and can worsen shallowing of the anterior chamber by decreasing the dimensions of the space 8,36–38 …”

Influence of Pilocarpine Eyedrops on the Ocular Biometric Parameters and Intraocular Lens Power Calculation

“…A recent clinical application of this agent is to manage presbyopia in the elderly [14]. Accommodation alteration of the eye, as one of the pharmacological efects of pilocarpine, is often seen in patients under treatment, which involve the axially thickening of the lens [15], the increase of the global AL [16], the forward movement of the lens [17], and the shallowing of the anterior chamber depth [18]. Tese changes may potentially infuence the ocular biometric measurement and may therefore result in an alteration in the IOL power calculation based on these parameters.…”