Assessing the accuracy of intracameral phenylephrine preparation in cataract surgery

Purpose: Unpreserved phenylephrine is often used as an off-licence intracameral surgical adjunct during cataract surgery to assist with pupil dilation and/or stabilise the iris in floppy iris syndrome. It can be delivered as a neat 0.2 ml bolus of either 2.5 or 10% strength, or in a range of ad-hoc dilutions. We wished to assess the accuracy of intracameral phenylephrine preparation in clinical practice. Methods: Phenylephrine 0.2 ml was analysed both neat (2.5 and 10%) and in diluted form (ratio of 1:1 and 1:3). Samples were analysed using the validated spectrophotometric method. Results: A total of 36 samples were analysed. The standard curve showed linearity for phenylephrine (R2 = 0.99). Wide variability was observed across all dilution groups. There was evidence of significant differences in the percentage deviations from intended results between dilutions (p < 0.001). Mean percentage deviation for 1:3 dilution was significantly greater than neat (p = 0.003) and 1:1 dilution (p = 0.001). There was no evidence of a significant difference between 1:1 and neat (p = 0.827). Conclusions: Current ad-hoc dilution methods used to prepare intracameral phenylephrine are inaccurate and highly variable. Small volume 1 ml syringes should not be used for mixing or dilution of drug. Commercial intracameral phenylephrine products would address dosage concerns and could improve surgical outcomes in cases of poor pupil dilation and/or floppy iris syndrome

The clinical utility of new combination phenylephrine/ketorolac injection in cataract surgery

Lola Elizabeth Lawuyi, Avinash Gurbaxani Moorfields Eye Hospital Dubai, Dubai, UAE Abstract: The maintenance of mydriasis throughout cataract extraction surgery and the control of ocular inflammation are crucial for successful surgical outcomes. The development of miosis during cataract surgery compromises the visualization of the surgical field and working space for surgeons. This may lead to complications that include posterior capsular tear and associated vitreous loss, longer surgical time, and postoperative inflammation. Postoperative inflammation is often uncomfortable and frustrating for patients. It causes pain, redness, and photophobia. This compromises the best-uncorrected vision following surgery and often leads to multiple clinic visits. This article examines the literature published on the current treatments used to manage mydriasis, pain, and inflammation in cataract extraction surgery. Combination phenylephrine/ketorolac injection offers an exciting new class of medication for use in cataract surgery. With the recent approval of Omidria™ (combination of phenylephrine 1% and ketorolac 0.3%) by the US Food and Drug Administration (FDA) for intraocular use, we review the clinical utility of this new combination injection in cataract surgery. PubMed, MEDLINE, and conference proceedings were searched for the relevant literature using a combination of the following search terms: cataract extraction surgery, pupil dilation (mydriasis), miosis, phenylephrine, ketorolac, Omidria™, intracameral mydriatic. Relevant articles were reviewed and their references checked for further relevant literature. All abstracts were reviewed and full texts retrieved where available. Keywords: cataract extraction surgery, ketorolac, mydriasis, miosis, Omidria™, phenylephrin