Cataract surgery: if it goes wrong and you get an infection
Rarely does cataract surgery go wrong or have post-operative complications, but it can, and you need to be aware of the risks involved.
The endophthalmitis case
Infection inside the eye is known as endophthalmitis and can occur after any cataract operation. Time to treatment is crucial in trying to achieve a good outcome. It has to be detected and treated as soon as possible. Some cataract operations take longer or are more complicated than a standard routine case, and these do take longer to settle down however in most cases the result is still excellent, it just takes a little longer to get off the anti-inflammatory drops.
When endophthalmitis occurs it is usually not a fault of the ophthalmic surgeon’s technique, but inadvertent entry into the eye of the normal bacteria found on your skin or eyelashes, or exceptionally rarely on instruments or in eye fluid infusions. Every care is made to avoid the risk of endophthalmitis with sterile draping for surgery, povidone-iodine eye drops at the start of the operation, and eye injection antibiotic at the end. However, it can occur rarely and unavoidably.
Treatment must not be delayed while waiting for the microbiology confirmation or effects of a trial of drops. All units doing intraocular cataract surgery have surgeons who know how to treat endophthalmitis, and they have clear pathways how to detect and treat this potentially devastating condition.
Endophthalmitis is a devastating complication of cataract surgery. I do not want to sound alarmist, but if you get any symptoms after cataract surgery, which include severe pain, rapid onset reduction of vision, progressive swelling or redness of the eye or smelly discharge from the eye after surgery, you should urgently see your ophthalmologist.
How is the endophthalmitis treated?
The eye surgeon will do a vitreous biopsy and anterior chamber tap. This means that they have to take a specimen from deep within the eye and from the front of the eye to try and find out what organisms such as bacteria or fungus are present in the eye.
The most prevalent bacteria found in confirmed endophthalmitis are streptococcus or staphylococcus.
By knowing which organism is growing they can then be sure that you are getting the best antibiotics after surgery. You will have received prophylactic antibiotics at the end of your operation and be putting in antibiotic drops at home after your cataract surgery, but there is still a small risk of endophthalmitis.
The treatment involves injecting antibiotics directly into the back chamber of the eye according to the protocol of the hospital who has worked closely with the pharmacist and the microbiologist to develop the best combination of antibiotics to use for you. They start this immediately and therefore once the results of the vitreous biopsy and anterior chamber tap comes through they will know whether you are on the right antibiotics. A small number of cases of post-operative endophthalmitis require vitrectomy surgery to clear the infection.
In summary, prevention and early diagnosis of endophthalmitis are key. It is uncommon to have this severe infection after cataract surgery however when it happens it needs urgent treatment.
Microbiological investigations are imperative with the aqueous tap and vitreous biopsy, both of which can be done under local anaesthetic. The specimens are sent for microbiology and on occasion, polymerase chain reaction to detect the DNA from the infecting organism, which has a higher sensitivity and shorter detection time particularly for negative culture samples.
Other investigations will be to make sure that you have no remote sites of infection, in other words, have caught the infection within your eye from your blood, such as a chest infection or an infected heart valve.
In summary: The management of endophthalmitis is to
- contain the infection,
- treat any systemic endogenous cause of infection, and
- treat it as an ophthalmic emergency requiring prompt therapy
with rapid administration of antibiotics before the culture result comes through using a combination of both topical, meaning eye drops on the eye and intravitreal injection of antibiotics.
A small number of patients may need vitrectomy in post cataract extraction endophthalmitis when the vision is very poor, and the risk of losing the eye and vision is high. A vitrectomy aims to remove an infection from the vitreous cavity behind the lens capsule.
Unfortunately, some patients lose all their vision and even their eye from endophthalmitis, hence I have spent so much time writing these blogs so that realistically patients know that the risk of endophthalmitis is minute, but real and cannot be fully eliminated.