March 2021

CATARACT

Performing cataract surgery with retina abnormalities


by Ellen Stodola Editorial Co-Director

 


A 75-year-old patient developed a posterior vitreous detachment
3 weeks after uncomplicated cataract surgery in his right eye.
Source: Christina Weng, MD, MBA

A 68-year-old patient with dry AMD (bottom) had a single-piece acrylic monofocal IOL placed in the capsular bag (top) during cataract surgery.
Source: Christina Weng, MD, MBA

When performing cataract surgery, it’s important to be aware of other conditions and comorbidities, including issues with the retina. Several physicians discussed how to handle patients with retina abnormalities prior to cataract surgery.

Retinal checks preoperatively

Dr. Charles said that it’s important to do a preop dilated peripheral retinal examination with an indirect ophthalmoscope to determine if there are retinal tears, holes, lattice, and areas of weakness. He said this check is very important for patients who are myopes, those with previous tears or retinal detachment, but it should be done on all patients.
Uday Devgan, MD, said that he will check the retinas of all patients who are having cataract surgery. “There are higher risk patients such as those with axial myopia, previous retinal issues like breaks or detachments, retinal vascular disease, and macular issues like epiretinal membrane and diabetic macular edema,” he said. “These high-risk patients are referred to our vitreoretinal colleagues for evaluation prior to cataract surgery.”
Christina Weng, MD, said that the exact timing for the exam will differ from provider to provider. She prefers to perform a dilated retinal examination approximately 1 month prior to planned cataract surgery for anyone with a history of high myopia or peripheral retinal issues, such as an old tear or lattice degeneration. “I prefer this timeframe because it is close enough to the surgery date that developing new pathology prior to the cataract extraction is less likely, but if any pathology is found, it potentially (although not always) could be treated without having to reschedule the surgery,” she said. “Additionally, it gives you the opportunity to counsel the patient about the low risk of retinal detachment associated with cataract surgery and to review return precautions with them; the latter is crucial since cataract surgery often induces a postoperative PVD.”
Dr. Weng added that if a patient had a recent retinal detachment, she prefers to wait at least 3 months before proceeding with surgery. 
In patients with a prior PVD, she will not necessarily bring them in for a preop evaluation if the PVD occurred in the remote past and there are no other risk factors; if the PVD occurred recently, however, she does like to perform a scleral-depressed examination preoperatively.

Cataract surgery in diabetics

Dr. Weng said historically, there was a concern that inflammation from cataract surgery could induce cytokine release and breakdown of the blood-retinal barrier that could theoretically worsen diabetic macular edema (DME). The literature is mixed when it comes to the possibility of cataract surgery inducing DME,1,2 but this association is less apparent in more recent studies that employ modern phacoemulsification techniques and technology, Dr. Weng said. 
“Remember that it can also be difficult to discern whether postoperative macular edema is truly an exacerbation of DME versus Irvine-Gass syndrome; a fluorescein angiogram can be helpful in these situations,” she said.
Additionally, Dr. Weng said that if a patient has no history of DME, she does not specifically ask to see these patients preoperatively (assuming that an OCT has been obtained by the cataract surgeon) or postoperatively unless they are experiencing visual symptoms. However, in patients with a recent history of or active DME, she likes to see them in the perioperative period to ensure that their retinal status is optimized before they go to the OR and that they do not require retinal treatment afterward. She recommends obtaining an OCT for all patients prior to cataract surgery.
According to Dr. Devgan, patients who have their diabetes under control and who have minimal background diabetic retinopathy without macular lesions tend to do very well with cataract surgery. “However, patients who have significant diabetic retinal disease, such as macular edema or proliferative vasculopathy, should be treated by a retinal colleague prior to cataract surgery,” he said. “If the patient has a cataract that is bad enough to impair visualization of the retina, our retinal colleagues will have us perform the cataract surgery first, and they may also premedicate with an intravitreal injection first.”
Dr. Charles also stressed that cataract surgery does not make DME worse, noting that he thinks inflammatory CME was likely misinterpreted as DME using OCT thickness data in studies that suggest that cataract surgery does increase DME. He also said that OCT is necessary before every cataract surgery.

Cataract surgery in dry AMD and wet AMD

When choosing an IOL for patients with AMD, Dr. Charles said not to use multifocal or EDOF IOLs. Multifocal IOLs can decrease contrast sensitivity and generally should be avoided in patients with macular disease, he said.
In terms of considerations for timing of the surgery with intravitreal injections, Dr. Charles said not to alter the injection cycle or interval. Cataract surgery must be performed in the middle of the injection interval (not the same day or immediately pre- or postop), he said.
Dr. Weng advised hydrophobic acrylic monofocal IOLs as the safest choice for patients with wet or dry AMD. 
“Presbyopia-correcting IOLs should be used with caution because of possible degradation in contrast vision and an approximately 15% loss of light from diffractive optics,” she said. “It may be beneficial to aim for distance vision so that the plus spectacles used for reading provide an added magnification boost.”  
Dr. Weng added that she does not routinely bring a patient in for a dedicated preop retinal check, assuming dry AMD patients are already being regularly followed and that wet AMD patients are on an established treatment regimen. “However, this again assumes that the cataract surgeon is obtaining a preoperative OCT in all patients to confirm no changes from baseline,” she added. “If not, I am always happy to see the patient beforehand.”
She said it’s important to remind AMD patients that their surgical outcomes may not match those of their friends and neighbors without retinal disease. “Assessing patients’ visual potential through examination and imaging is critical in this cohort so that their expectations can be properly set.”
In terms of timing of surgery with any intravitreal injections, Dr. Weng said that she tries not to disrupt the schedule of intravitreal injections in wet AMD patients, although she prefers not to inject on the first postoperative day. “Timing the surgery so it falls between injections is ideal if possible,” she said.
When handling a patient with AMD, Dr. Devgan said he will coordinate care with retinal colleagues, and for most of these patients, the best choice is a monofocal IOL and a goal of plano spherical equivalent. “We explain to the patient that the eye is like a camera; with cataract surgery, we are changing to a new and improved lens, but the film of the camera, the retina, is still affected by the macular degeneration,” he said. “If the retina doctor deems that an intravitreal injection is needed prior to the cataract surgery, we will certainly heed that advice.”

Cataract surgery after pars plana vitrectomy or intravitreal injections

When performing cataract surgery after a pars plana vitrectomy or intravitreal injections, Dr. Charles said to look for vitrectomy-related defects in the posterior capsule in the office with a widely dilated pupil and remain cautious and aware during cataract surgery.
Patients with a history of pars plana vitrectomy may pose surgical challenges due to weakened zonules, posterior capsular violation, floppy capsule due to absence of vitreous, or poor dilation, Dr. Weng said, adding that intravitreal injections have also been associated with weakened zonules, as well as an increased risk of posterior capsular rupture.3 “Having multiple types of IOLs and iris expansion/capsular tension stabilizing devices available as well as avoiding significant traction on the zonules during phacoemulsification is advisable,” she said.

About the physicians

Steve Charles, MD
Charles Retina Institute
Germantown, Tennessee

Uday Devgan, MD
Clinical Professor of Ophthalmology
Jules Stein Eye Institute, UCLA
Chief of Ophthalmology
Olive View UCLA Medical Center
Los Angeles, California

Christina Weng, MD, MBA
Associate Professor of Ophthalmology
Fellowship Program Director
Vitreoretinal Diseases and Surgery
Cullen Eye Institute
Baylor College of Medicine
Houston, Texas

References

1. Romero-Aroca P, et al. Nonproliferative diabetic retinopathy and macular edema progression after phacoemulsification: prospective study. J Cataract Refract Surg. 2006;32:1438–1444.
2. Pollack A, et al. Progression of diabetic retinopathy after cataract extraction. Br J Ophthalmol. 1991;75:547–551.
3. Siddiqui MZ, et al. Visual outcomes and intraoperative complications of cataract surgery in nAMD: A multicenter database study. Poster presentation at the 2020 American Academy of Ophthalmology Virtual Congress.  

Relevant disclosures

Charles: None
Devgan: None
Weng: None

Contact

Charles: scharles@att.net
Devgan: devgan@gmail.com
Weng: christina.weng@bcm.edu

Take note of other retinal issues

Dr. Devgan offered several other retinal situations to be aware of and shared cases from his
Cataract Coach website.

Vitreomacular traction

If you see vitreomacular traction on the OCT, Dr. Devgan said not to rush into cataract surgery because when the thick cataractous lens is replaced by the thin IOL, the vitreous will shift. Vitreomacular traction can be hard to detect, he noted. It can lead to PVD and potentially even full-thickness macular hole, cystoid macular edema, and poor vision. When vitreomacular traction is detected, Dr. Devgan suggested delaying cataract surgery and coordinating with retina specialists who may inject lytic agents or rarely do a pars plana vitrectomy.

Retinitis pigmentosa

Patients with retinitis pigmentosa may develop cataract at an earlier stage, and with this underlying retinal disease, the cataract surgery may only improve their vision slightly. These patients may have zonular weakness during surgery and may also have a higher risk of postop retinal complications like CME. According to Dr. Devgan, these patients are also more prone to capsular phimosis after surgery.

Epiretinal membrane

Dr. Devgan noted that up to 20% of cataract patients may have epiretinal membrane, and it’s important to critically evaluate the retina prior to the cataract surgery. Some epiretinal membranes may have only a minimal effect on vision, but larger ones can cause macular distortion and issues with vision following cataract surgery. They could also add to potential postop complications such as cystoid macular edema.

Performing cataract surgery with retina abnormalities Performing cataract surgery with retina abnormalities
Ophthalmology News - EyeWorld Magazine
283 110
220 211
,
2021-03-02T11:51:47Z
True, 3