To enhance patient safety and outcomes during cataract surgery, surgeons and patients need to be prepared and understand potential complications. Prompt action is essential to prevent irreversible vision loss in cases of endophthalmitis, with intravitreal antibiotics and vitrectomy being potential treatments. According to a recent report*, surgeon experience, preoperative evaluation and postoperative care significantly lower complication rates.
Posterior capsule rupture (PCR) is one of the most significant complications that can occur during cataract surgery, which can result in vitreous loss. Serious morbidities, including retinal detachment, cystoid macular edema, uveitis, glaucoma and dislocated intraocular lenses (IOLs) are associated with PCR. Prompt surgical intervention and appropriate management are necessary to prevent any further complications.
Although rare, endophthalmitis is a serious complication that involves inflammation and infection inside the eye. It can cause vision loss and requires immediate treatment with intravitreal antibiotics. Strict adherence to sterile techniques, preoperative prophylactic antibiotics and proper wound care can help reduce the risk of this complication.
Cataract surgery can also occasionally lead to an increase in eye pressure, which can result in glaucoma. This can be managed with medications or additional procedures to control intraocular pressure (IOP).
While these complications can occur, the rate of occurrence is relatively low, and most cataract surgeries are successful without complications.
From common complications…
“Cataract surgery is the most common surgery performed by ophthalmologists,” said Prof. Mae-Lynn Catherine Bastion, professor of ophthalmology (vitreoretina) and senior consultant ophthalmologist at the National University of Malaysia (UKM). She noted that an increase in surgical experience is associated with a gradual decline in the rate of complications.*
The most common complication of cataract surgery is blurred vision,which is due to the temporary swelling of the cornea and should clear up by the next day, she explained.
A relatively common complication is posterior capsular opacification, which occurs when the capsule into which the lens is inserted becomes thickened due to a scarring reaction. This condition can be treated in the eye clinic with a low-risk laser procedure, which is painless and takes just five minutes to perform in a cooperative patient. For pain relief, only eye drops are needed.
Another common complication is redness of the eye, which may be due to local anesthesia. “This clears up without specific treatment in one to two weeks. Eye redness and itching may also be a sign of an allergy to eye drop constituents or dry eye that tends to worsen after any eye surgery,” she continued. Both of these complications can be managed by discontinuing the use of the current eye drops and switching to a more well tolerated type, or by using lubricating eye drops.
… To rare and complex cases
“Other complications are fortunately much rarer. These include a tear or break in the capsule, which the surgeon immediately treats by performing a vitrectomy. According to one published report,* this occurs in only 0.99% of all surgeries,” added Prof. Bastion.
“Most often, a vitrectomy is required (in cases of PCR), and prompt intervention is crucial to preserve visual outcomes,” shared Dr. Noor Aniah Azmi, medical director and consultant refractive surgeon at the Ikonik Eye Specialist and General Health Centre in Kuala Lumpur, Malaysia. Dr. Azmi once encountered a PCR that resulted in a dropped nucleus.
“As the vitreoretinal surgeon was retrieving the dropped nucleus, a retinal tear occurred. It was a long surgery, but the patient ended up with good post-op vision eventually,” she continued. “This showcases the importance of expertise and comprehensive management in complex cases.”
One of the many challenges cataract surgeons sometimes face is weak or missing zonules. This is when the lens becomes weak, causing it to wobble during surgery, said Prof. Bastion. In most cases, zonulysis is detected
during pre-surgery examination by the doctor, but there is a possibility of it being easily missed.
“During surgery, if there is less than 180 degrees of zonular weakness, then the surgeon may implant a capsular tension ring to support the capsule. Then good outcomes are possible,” Prof. Bastion chimed in.
Bleeding during cataract surgery is rare. However, some are at risk of experiencing a devastating type of bleeding from large vessels in the choroid. These vessels can bleed into the space above the choroid very suddenly during surgery, resulting in a blood-filled eye.
The surgeon should immediately close the operation wound and refer the patient to a vitreoretinal surgeon, who may be able to salvage the situation if the retina can be reattached, said Prof. Bastion.
Another less common complication that can occur after surgery is an unexpected discrepancy in the calculated power. This may occur despite careful lens calculation before the operation. This error is most common after refractive surgery and in patients with high eye power. In these cases, the patient may still need to wear glasses to correct the power difference. They could also exchange the lens, which is a risky procedure, or undergo further refractive surgery if not contraindicated.
Retinal detachment is another rare complication, which needs to be repaired by a retinal surgeon. The outcomes can be favorable, provided the macula is not involved or is quickly reattached.
According to Prof. Bastion, while endophthalmitis is a serious complication, it occurs very rarely at a rate of 0.01% due to effective prevention measures, including intravitreal antibiotics.
Time is of the essence when it comes to prevention
Prevention includes paying attention to eye hygiene in the weeks leading up to surgery, as well as ensuring diseases that reduce immunity, such as diabetes, are well controlled before surgery. However, once the infection has occurred, time is of the essence. It usually develops within the first five days of the operation. Symptoms include pain, blurred vision with floaters, swelling, and increasing eye redness — which warrant an immediate visit to the emergency department or the eye clinic. Early intervention can save a patient’s vision. Intravitreal antibiotics are prescribed, but if vision drops further, then a vitrectomy is performed.
Dr. Azmi agrees that swift and decisive action is essential to prevent irreversible vision loss in cases of endophthalmitis. “Prompt administration of intravitreal antibiotics is crucial. A vitrectomy may be necessary to effectively clear the infection and safeguard the vision,” she said.
“Surgeon experience, comprehensive preoperative evaluation, and postoperative care significantly influence the complication rates. By understanding the potential complications and taking appropriate measures, we can enhance patient safety and deliver positive outcomes for the patients,” concluded Dr. Azmi.
Aaronson A, Viljanen A, Kanclerz P, Grzybowski A, Tuuminen R. Cataract complications study: an analysis of adverse effects among 14,520 eyes in relation to surgical experience. Ann Transl Med. 2020;8(22):1541.
Editor’s Note: A version of this article was first published in CAKE Magazine Issue 19.