Pupillary Pathways

The Scoop on Dropless Cataract Surgery

Posted by Amanda Dexter on Apr 21, 2016 8:00:00 AM
Amanda Dexter
Dr. Amanda K. Dexter received her optometric training at Southern California College of Optometry in Fullerton, California, where she was Class of 2010 Valedictorian. She also completed a residency in Primary Care and Ocular Disease at the Veteran's Affairs Hospital in San Diego, California. Dr. Dexter is the Manager and Program Coordinator for OptoPrep, the premiere online study resource for the NBEO Part I & II.

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About a year ago, I sent a patient to a local cataract surgeon for a cataract evaluation due to his complaints of decreased visual acuity, glare and haloes at night, and difficulty completing some of his normal daily tasks.

He presented with visual acuities of 20/40 OD and 20/50 OS, which decreased further with glare simulation. He had 2-3+ nuclear sclerosis and 2+ cortical spoking in both eyes. The surgeon decided to proceed with cataract surgery in the left eye first, using a basic lens for best distance correction and utilizing LenSx technology.

The patient returned to the surgeon for his 1 day post-operative exam and came to me for his 1 week follow-up. During the 1 week post-op, I asked the patient which drops he was using and how often he was using them.

He replied stating that he had not been given and had not been using any drops after his cataract surgery! I was a little confused and a little worried that there was some miscommunication between the patient and the surgeon, but after looking further into the operative report, I had found that the ophthalmologist had used an intraoperative intravitreal injection of a steroid and antibiotic.

Because of this, the patient did not need to use any post-operative topical medications, and the patient was quite pleased with this. Come to find out, this particular surgeon had just begun “dropless cataract surgery” for his patients and believed that there were many advantages to this type of medication delivery vs. standard topical post-operative medications. 

What is Dropless Cataract Surgery?

Dropless cataract surgery involves a transzonular delivery of a medication called TriMoxi. TriMoxi is compounded, preservative-free triamcinolone acetone and moxifloxacin. It is designed to be delivered to the posterior chamber, directly into the vitreous. After the intraocular lens implant is in place during cataract surgery, and prior to removing viscoelastic, the surgeon will pass a canula through the corneal incision site, over the anterior capsule, underneath the iris, and then penetrate the zonules into the anterior vitreous and inject the medication into the vitreous itself. Approximately 0.3mg of triamcinolone and 0.2mg of moxifloxacin are delivered intraocularly. (There is also another medication that some surgeons use known as TriMoxiVanc, which is comprised of Triamcinolone, Moxifloxacin, and Vancomycin). 

Advantages of Dropless Cataract Surgery

  • Compliance: Getting patients to comply with their post-cataract surgery topical medication regimen can be quite challenging, to say the least. Far more often that we may think, patients do not take their medications in the way we prescribe them. Some of this has to do with the fact that patients simply forget to take the drops. Patients who undergo cataract surgery are typically of older age and can have dexterity issues that can cause difficulty with proper instillation of the medications. Some patients also report that drops will burn, sting, or cause redness, so they end up not using the drops as prescribed to limit these side effects. Dropless cataract surgery essentially eliminates the issue of having to rely on patients to use drops as directed. Remember that following cataract surgery, patients are typically required to take 3 medications (antibiotic, steroid, and NSAID), some of which may be used up to 3-6 weeks post-operatively. 
  • Cost: As mentioned above, following cataract surgery, patients are typically prescribed 3 separate topical medications; an antibiotic, a steroid, and an NSAID. The cost of these medications can reach upwards of hundreds of dollars in out-of-pocket expenses for patients. This can be a significant burden to patients on a fixed income, which is common in the cataract surgery population. Because of this financial issue, this can also be a barrier for certain patients for moving forward with cataract surgery as they may not be able to afford all the associated costs. Additionally, I’ve seen that patients will stretch the doses of their eyedrops to avoid needing refills. Dropless cataract surgery significantly reduces the out-of-pocket expenses for many cataract patients.
  • Less Confusion: Dropless cataract surgery minimizes post-operative instructions and eliminates confusion associated with the administration of topical eye drops. I’ve co-managed many patients undergoing cataract surgery and have spent much time reviewing the medication protocol with the patient (both pre- and post- cataract surgery), and responding to phone calls from the patient, patient’s family, and pharmacies regarding their medications. 
  • Lower Rate of Infection: Post-operative endophthalmitis is one of the most devastating complications following cataract surgery. Studies have shown that as compared to topical eye drops, dropless cataract surgery carries a greatly reduced risk for post-op endophthalmitis. This is likely due to the fact that when bacteria enters the eye, it usually colonizes in the vitreous because the vitreous is very nutrient-rich. In dropless cataract surgery, the medication is placed in the exact location that bacteria want to grow, rather than on the cornea, and hoping that it diffuses into the eye and eventually to the vitreous. 
  • Minimal Risk: Initial studies on dropless cataract surgery have shown that the procedure is very safe and effective. There is a low incidence of breakthrough inflammation that would require treatment with topical steroid drops. Additionally, in a high-risk population, the rate of CME with the dropless technique matched the rate in a similar population using a 3-week standard topical drop regimen. Other anticipated complications of dropless cataract surgery, such as zonular injury, vitreous presentation, and retinal detachment have not been seen in tens of thousands of cases reported by surgeons who frequently perform this technique. Surgeons using the dropless technique with premium IOLs are not seeing an increase in Z-syndromes, and toric lens malrotation has also not been reported. Another important factor to consider is a possible intraocular pressure (IOP) spike in steroid responders with dropless cataract surgery. However, this has also been shown to happen about as often as it does with conventional topical drops, and can be managed with the addition of topical hypotensive medications.

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Disadvantages of Dropless Cataract Surgery 

  • Post-Op Floaters: With the dropless cataract surgery technique, many patients will state that they notice an increase in floaters or visual obscurations directly following surgery, and will even often report a decrease in visual acuity. This is due to the opaque nature of the drug, and the symptoms are often rarely noticeable by day 14. A disadvantage of this is that these symptoms can mimic that of a post-op retinal detachment, so they should be taken seriously and not just brushed-off and blamed on the medication. You should also be sure to educate the patients that floaters are very common after surgery with the dropless technique so that they aren’t worried or surprised following surgery. 
  • Potential Post-Op IOP Spikes: Any time steroids are injected into the eye, there is the potential risk for an elevation of intracocular pressure in steroid responders. As previously noted, the risk of an IOP spike has shown to be similar in those with topical steroid use as it is with those undergoing dropless cataract surgery. In fact, most of the cases of increased IOP can be attributed to retained viscoelastic material rather than a true steroid response. However, in these patients, the addition of a topical hypotensive medication will be necessary. 
  • Breakthrough Inflammation: Studies have shown that in approximately 2% of patients, evidence of breakthrough inflammation occurred, requiring the addition of topical steroids during the post-op period (it was slightly higher in those with ERM, and in those who developed CME). Therefore, this procedure may not be completely “dropless” as some patients with residual inflammatory cells in the anterior chamber, corneal edema, cystoid macular edema, or those with complaints of photophobia, redness, or foreign body sensation should have a topical steroid drop added. Additionally, some patients will also need a topical NSAID because of diabetes, ERM, or premium IOL implantation, as the rate of CME is higher in these groups. 
  • Foreign Body Sensation: I have also found that patients undergoing the dropless procedure have reported an increase in foreign body sensation post-operatively. This is presumably due to the lack of topical anti-inflammatory drugs at the wound site itself. In patients with this complaint, a steroid, or even just artificial tears can be added to the post-op regimen. 
  • Additional Pre-Op Counseling: Although counseling related to the use of post-operative eye drops is much reduced, these patients do require slightly more counseling pre-operatively in order to fully explain to the patients that they will experience a brief reduction in visual acuity after surgery. It is also very important to make sure that they understand that they will also likely “see” the medication appear as floaters in their vision for several days following the surgery. Even though this is explained prior to surgery, I have still received several phone calls from concerned patients who state that their vision is “foggy” and they see “floaters and shadows.” Again, you must also be careful that these symptoms are in fact due to the medication, and not a more serious complication. 

Summary

Based on current studies of the thousands of patients who have undergone dropless cataract surgery, this procedure appears to be safe, effective, and ultimately beneficial to the patient for many reasons. If you are going to be co-managing a patient in which the surgeon utilizes this technique, you should be fully aware of all of the advantages, disadvantages, potential side effects, and cases in which topical drops may need to be utilized. 

-Dr. Dexter 

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Topics: Cataracts