Preoperative techniques to ensure optimal patient outcomes in refractive cataract surgery

Ophthalmologists have a variety of techniques and technologies to ensure good patient results in refractive cataract surgery. First, patient selection is a key to success. It is important to consider the patient’s personality and expectations when matching a patient with a refractive multifocal or accommodating IOL.

A second important factor is a healthy eye. For example, patients with pseudoexfoliation should not receive IOL implants, unless the pseudoexfoliation is mild or the patient is older and pseudoexfoliation will not have an effect on him or her. Also, patients who have experienced trauma in the eye or zonular dehiscence will not receive the benefits of an IOL and will not be happy with the results.

Patient needs should match the IOL chosen for that particular patient. No one IOL is perfect for each patient.

—Rosa Braga-Mele, MEd, MD, FRCS(C)

Ophthalmologists should be cautious with patients who have undergone previous refractive surgery. If an ophthalmologist decides to implant an IOL in a patient who has previously undergone refractive surgery, then the patient should be implanted with an aspheric IOL. Otherwise, the patient may be dissatisfied due to unwanted visual aberrations. Ophthalmologists should also be cautious with patients with astigmatism, for example, a cylinder greater than 2.5 D.

Patient needs should match the IOL chosen for that particular patient. No one IOL is perfect for each patient. Using a questionnaire such as the Dell and Maloney questionnaire (Figure) will help ophthalmologists better match the IOL to the patient’s needs.^1,2

It is important to explain all of the possible outcomes to the patient. Patients who are told they likely will have glare and halo are less likely to complain postoperatively. Ophthalmologists who undersell and over deliver will find they have happier patients than ophthalmologists who give patients lofty expectations from the IOLs.

NSAIDs

The goal of nonsteroidal anti-inflammatory drugs is the inhibition and treatment of cystoid macular edema (CME), management of postoperative inflammation and prevention of intraoperative miosis during cataract surgery.

Some adverse effects are associated with conventional NSAID therapy in terms of the mechanism of action of the cyclooxygenase pathway. Some patients complain of burning and irritation, although with currently available NSAIDs, this complaint is not as prevalent. Reports of delayed wound healing are associated with the use of NSAIDs.^3,4 Ophthalmologists should look for keratitis sicca preoperatively, because NSAIDs should not be used in patients with this condition. NSAIDs should also be avoided in patients with rheumatoid arthritis.

A study by McColgin and Raizman compared the efficacy of postoperative topical NSAIDs plus a corticosteroid to postoperative corticosteroid use alone in reducing the incidence of CME.⁵ The group receiving the NSAID and the corticosteroid had a 0% CME rate at week 6 vs. a 12% CME rate in the group receiving just a corticosteroid. NSAID use has been proven effective in minimizing the incidence of CME when used preoperatively and postoperatively.^5,6

Considerations must be made for at-risk patients, such as patients with diabetes, previous trauma to the eye or other diseases that will increase the likelihood of blood vessel leakage. For these patients, NSAIDs should be administered 1 week preoperatively and continued 4 weeks to several months postoperatively. Patients who are not at risk should begin NSAID treatment 1 to 2 days preoperatively and continue for 4 weeks postoperatively.^5,7

Patient questionnaire
Figure: Patient questionnaire
Figure. A questionnaire can help ophthalmologists better match an IOL to the patient's needs.

Maloney WF

Antibacterial prophylaxis and endophthalmitis

The goal of antibacterial prophylaxis is the prevention of endophthalmitis. Endophthalmitis rates are higher than past reports indicate.⁸A current theory is that clear corneal incisions may promote endophthalmitis if there is not a proper incision or if a suture is not used.^9,10 Surgical risk factors include wound architecture, surgical complications and choice of prophylactic antimicrobial agent.^11,12 Sixty-nine percent of patients from the Endophthalmitis Vitrectomy Study presented a bacterial-positive culture, with the most common being gram-positive coagulase-negative organisms.^13,14 Ophthalmologists must treat patients with an antibiotic that covers a broad spectrum because of gram-positive and gram-negative organisms that can enter the eye and the patient’s flora. The antibiotic should have good, fast-acting penetration, low incidence of resistance and good bioavailability. Additionally, ophthalmologists should note that fourth-generation fluoroquinolones have demonstrated reduced resistance when choosing an antibiotic agent for treatment.^15-18

To limit resistance, ophthalmologists should employ appropriate antibiotic use, including acute use, not chronic, and a short-term, high-dose surgical prophylaxis.^19,20 Antibiotics should be dosed appropriately, not tapered,¹⁵ and use of the newer generation antibiotics is less likely to select out resistant strains.^21,22

Skin preparation is important to prevent endophthalmitis. Studies by Isenberg and Miño de Kaspar showed using povidone-iodine alone provides a high bacteria kill rate, but a combination of 3 days of fluoroquinolone plus povidone-iodine irrigation preoperatively resulted in a 95% reduction of culture positivity of the conjunctiva, which is a higher rate then povidone- iodine alone. ^23,24Additionally, conjunctival preparation should include an application of povidone-iodine in addition to a topical antibiotic to reduce preoperative ocular surface flora.^25,26

Conclusion

Patient selection based on expectations and a proper preoperative workup is essential to patient satisfaction in refractive cataract surgery. The steps taken preoperatively are just as important as the surgery itself. If ophthalmologists employ available NSAIDs and antibiotics, then they will ensure patient satisfaction.

References

Dell SJ. Cataract and Refractive Lens Exchange Questionnaire. Available at: www.crstoday.com/Pages/DellIndex.doc. Last accessed April 23, 2008.
Maloney WF. Presbyopia success depends on comprehensive preop evaluation. Ocular Surgery News. August 1, 2005. Available at: http://www.osnsupersite.com/view.asp?rID=18891. Last accessed April 23, 2008.
Flach AJ. Topical nonsteroidal antiinflammatory drugs in ophthalmology. Int Ophthalmol Clin. 2002;42(1):1-11.
Mah FS, Dhaliwal DK, Barad R. Do NSAIDs case wound-melting following uncomplicated, small-incision, scleral-tunnel phacoemulsification? Paper presented at: Annual Meeting of the American Society of Cataract and Refractive Surgery. May 20-24, 2000; Boston, Mass.
McColgin AZ, Raizman MB. Efficacy of topical Voltaren in reducing the incidence of post operative cystoid macular edema. Invest Ophthalmol Vis Sci. 1999;40:S289.
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O’Brien TP. Emerging guidelines for use of NSAID therapy to optimize cataract surgery patient care. Curr Med Res Opin. 2005;21:1131-1137.
West ES, Behrens A, McDonnell PJ, et al. The incidence of endophthalmitis after cataract surgery among the U.S. Medicare population increased between 1994 and 2001. Ophthalmology. 2005;112:1388-1394.
Lalwani GA, Flynn HW Jr, Scott IU, et al. Acute-onset endophthalmitis after clear corneal cataract surgery (1996-2005). Clinical features, causative organisms, and visual acuity outcomes. Ophthalmology. 2008;115(3):473-476.
Endophthalmitis Study Group, European Society of Cataract & Refractive Surgeons. Prophylaxis of postoperative endophthalmitis following cataract surgery: Results of the ESCRS multicenter study and identification of risk factors. J Cataract Refract Surg. 2007;33(6):978-988.
Schentag JJ. Pharmacokinetic and pharmacodynamic predictors of antimicrobial efficacy: Moxifloxacin and Streptococcus pneumoniae. J Chemother. 2002;14(Suppl)2:13-21.
Metzler K, Hansen GM, Hedlin P, et al. Comparison of minimal inhibitory and mutant prevention drug concentrations of 4 fluoroquinolones against clinical isolates of methicillin-susceptible and -resistant Staphylococcus aureus. Int J Antimicrob Agents. 2004;24:161-167.
Han DP, Wisniewski SR, Wilson LA, et al. Spectrum and susceptibilities of microbiologic isolates in the Endophthalmitis Vitrectomy Study. Am J Ophthalmol. 1996;122:1-17.
Speaker MG, Milch FA, Shah MK, et al. Role of external bacterial flora in the pathogenesis of acute postoperative endophthalmitis. Ophthalmology. 1991;98:639-649.
Major JC Jr., Flynn HW Jr., Miller D, et al. Antibiotic sensitivities and visual acuity outcomes in endophthalmitis caused by methicillin-sensitive (MSSA) versus methicillin-resistant (MRSA) Staphylococcus aureus. Poster 5282/B697. Presented at: Annual Meeting of the Association for Research and Vision in Ophthalmology; May 4, 2006; Fort Lauderdale, Fla.
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Mather R, Karenchack LM, Romanowski EG, Kowalski RP. Fourth generation fluoroquinolones: New weapons in the arsenal of ophthalmic antibiotics. Am J Ophthalmol. 2002;133:463-466.
Kowalski RP, Dhaliwal DK, Karenchak LM, et al. Gatifloxacin and moxifloxacin: An in vitro susceptibility comparison to levofloxacin, ciprofloxacin and ofloxacin using bacterial keratitis isolates. Am J Ophthalmol. 2003;136:500-505.
Aguilar L, Giménez MJ, Garcia-Rey C, Martín JE. New strategies to overcome antimicrobial resistance in Streptococcus pneumoniae with beta-lactam antibiotics. J Antimicrob Chemother. 2002;50(Suppl S2):93-100.
Keegan JM, Rhames T, Boersma B. Development of a strategy for decreasing multi-drug resistant bacteria with implementation of a program emphasizing appropriate antibiotic utilization and strict infection control measures in western South Dakota. S D J Med. 2002;55:401-404.
Schedletzky H, Wiedemann B, Heisig P. The effect of moxifloxacin on its target topoisomerases from Escherichia coli and Staphylococcus aureus . J Antimicrob Chemother. 1999;43(Suppl B):31-37.
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Isenberg SJ, Apt L, Yoshimori R, Khwarg S. Chemical preparation of the eye in ophthalmic surgery. IV. Comparison of povidone-iodine on the conjunctiva with a prophylactic antibiotic. Arch Ophthalmol. 1985;103:1340-1342.
Miño de Kaspar H, Chang R, Egbert P, et al. Greater elimination of conjunctival bacteria after preoperative irrigation with 10cc of 5% povidone-iodine. Paper presented at: Annual Meeting of the American Academy of Ophthalmology; October 22, 2002; Orlando, Fla.
Speaker MG, Menikoff JA. Prophylaxis of endophthalmitis with topical povidone-iodine. Ophthalmology. 1991;98:1769-1775.
Apt L, Isenberg SJ, Yoshimori R, Spierer A. Outpatient topical use of povidone-iodine in preparing the eye for surgery. Ophthalmology. 1989;96:289-292.