Carbachol solution (0.01%) is an agonist of M cholinoceptor and skeletal muscle N cholinoceptor, and it is used to play miotic effect and open peripheral iridectomic hole during the surgery of implantable collamer lens (ICL) implantation in order to lower intraocular pressure (IOP). However, the anterior chamber injection of 0.01% carbachol solution often causes relevant complications, while whether lower dose of carbachol solution is effective and safe is unclear.

This study was to compare the effectiveness and safety between 0.01% carbachol solution and 0.005% carbachol solution after anterior chamber injection during the ICL implantation.

One hundred and fifty-two eyes of 76 cataract patients were included in Daping Hospital of Third Military Medical University from September 2014 to September 2015.ICL implantation and periphery iridectomy were carried out on both eyes of the patients and the 0.01% carbachol solution was injected into the anterior chamber during the surgery of the right eyes and 0.01% carbachol solution was used in the left eyes.The operation duration and IOP at postoperative 2 hours and systemic choline-like reaction were compared between 0.01% carbachol solution group and 0.005% carbachol solution group.

The mean operation duration was (11.86±2.39) minutes and (11.22±1.85) minutes in the 0.01% carbachol group and 0.005% carbachol group, without significant difference between two groups (t=1.851, P=0.066). IOP was (15.76±2.18)mmHg and (13.58±2.24)mmHg in the 0.01% carbachol group before and after surgery, and those in the 0.005% carbachol group was (15.70±2.35)mmHg and (13.12±2.17)mmHg, there was no significant difference in the IOP between the two concentrations of carbachol (F_group=0.986, P=0.322). The IOP at postoperative 2 hours was lower than that before operation, the difference was statistically significant(F_time=97.339, P=0.000). There was no interaction between drug concentration and time (F_correlation=0.772, P=0.381). The incidences of complications, such as dizziness, nausea and vomiting, were lower in the 0.005% carbachol group than those in the 0.01% carbachol group (χ²=13.01, 5.16, 4.03, all at P<0.05).

Carbachol solution (0.005%) can play intraoperative miosis effect and maintain effective operation duration in ICL implantation.In addition, the application of 0.005% carbachol solution is quite safe in both intraoperation and postoperation.

Carbachol; Lens implantation, intraocular; Phakic intraocular lenses; Choline-like reaction; Myopia/therapy; Anterior chamber injection; Human