Safety of intracameral mydriasis in phacoemulsification cataract surgery

We read with great interest the article by Lundberg and Behndig1 concerning the use of an intracameral injection of cyclopentolate, phenylephrine, and lignocaine to dilate pupils peroperatively in phacoemulsification cataract surgery. From the article's conclusion, this technique was not only rapid, effective, and a safe alternative to conventional topical mydriasis in phacoemulsification, it also simplified preoperative routines and may reduce the risk for cardiovascular side effects.2–5 We conducted a small pilot study of 10 patients having routine phacoemulsification cataract surgery. Patients with uncontrolled hypertension, unstable cardiac arrhythmia, and children were excluded, as were any eyes with iris or pupillary abnormalities (synechias, pseudoexfoliation). Based on the technique described above, we used an intracameral cocktail prepared aseptically in the operating room from widely available diagnostic reagents. The cocktail consisted of 0.1 mL minims cyclopentolate hydrochloride 1% (cyclopentolate 0.1%), 0.15 mL minims phenylephrine hydrochloride 10% (phenylephrine 1.5%), and 0.5 mL preservative-free lignocaine hydrochloride 2% (lignocaine 1%) made up to 1.0 mL with 0.25 mL of balanced salt solution. This was then divided by 5 for aliquots of 0.2 mL. Only 0.15 mL of the cocktail was administered intracamerally through a paracentesis just before capsulorhexis was performed. All the patients' vital signs were noted (eg, pulse and blood pressure) throughout the procedure. The result was almost instantaneous mydriasis without any adverse events. Neither the surgeon nor the patients reported difficulty or discomfort during the cataract operation. We monitored the blood pressure and pulse of all cases preoperatively and perioperatively throughout the procedure and found that mean changes in systolic blood pressure was 8.95 mm Hg (minimum, 4.375 mm Hg; maximum, 13.5 mm Hg), diastolic blood pressure was 6.675 mm Hg (minimum, 0.5 mm Hg; maximum, 13.375 mm Hg), and pulse was 10.1 beats/min (minimum, 2.5 beats/min; maximum 23.375 beats/min). These changes were minimal and did not differ from those expected in patients whose pupils had been dilated preoperatively in the conventional manner. There is no difference between the components used by Lundberg and Behndig and ourselves, and, therefore, we did not duplicate their research with regard to endothelial safety. No preservatives were present in any of the solutions used. All 10 patients were examined the following day and 2 weeks after surgery. There were no cases of undue postoperative inflammation or signs of corneal decompensation on slitlamp biomicroscopy. Postoperative anterior uveitis resolved completely with a course of topical steroids by week 2. There was postoperative improvement in both subjective and objective visual acuity in all the patients in this study. The intracameral route of administering mydriatics delivers minute doses of the drugs to the target organ to achieve the desired effect, thus minimizing potential cardiovascular side effects. The preparation of the cocktail in the operating room is more cost effective compared to the topical technique of mydriasis. The simplification of preoperative routines would reduce the demand on nursing time and staff, as well as producing a small recurrent cost saving. Patients are spared the discomfort of intensive topical mydriatics preoperatively; although apparently trivial, our patients considered this a significant benefit. From this study, we concur that the use of intracameral mydriatics in phacoemulsification cataract surgery is safe, rapid, and an effective alternative to conventional topical mydriasis. With the current high turnover of cataract surgery, intracameral mydriasis can reduce the duration of stay within the outpatient surgical units. Since the end of this pilot study, we have undertaken 280 further cases without experiencing any unexpected outcomes. We would support the introduction of this technique in routine, uncomplicated cases.