Do the benefits outweigh the risks of immediate sequential cataract procedures?
Juan J Mura MD
With the incidence of immediate sequential bilateral cataract surgery (ISBCS) ranging from nearly zero in the USA, Japan and much of Europe to 50% in Finland and 80% in the Canary Islands (Spain), the practice remains controversial. The debate surfaced once again at the 36th Congress of the ESCRS in Vienna.
On the plus side, ISBCS has clear advantages for patients, hospitals and health systems, said Juan J Mura MD, MHA, of the University of Chile, Santiago. These include faster visual rehabilitation, fewer pre- and post-op visits, more efficient OR time, shorter waiting lists, lower price and most importantly, cost-effectiveness (providing better “value for money” when you compare ISBCS with delayed strategy – DSBCS), with hospital costs about $1,600 less in Canada and €500 less in the Canary Islands, and savings per patients ranging from €120 to €850, the effectiveness (using QALYs) is higher, which means maximised health for the available resources (Malvankar-Mehta M et al. Can J Ophthalmol 2013:48(6). Canary Islands government analysis). These savings and increased efficiency will become more important as demand for cataract surgery rises, Dr Mura noted. “We have to remember that resources are always scarce, especially with what is happening to our population, which is ageing rapidly.”
Quicker visual rehabilitation is also a significant benefit, Dr Mura said. Patients undergoing ISBCS have better visual function and fewer difficulties performing daily tasks than patients undergoing separate procedures after the first surgery, even in the three-to-four months after a second eye surgery ISCBS maintains better patient-reporterd evaluation, although outcomes are equivalent after six-to-12 months (Lundstrom M et al. J Cataract Refract Surg. 2006;32(5):826-30.). However, there are other practical connections; for example, between first and second cataract surgeries the risk of falls resulting in hospitalisation rises to 2.14 times pre-surgery levels, and falls back to about 1.34 times after the second surgery (Meuleners L et al. Age and Aging 2014; 43:341-346).
With the advent of optical biometry, refractive predictability also has improved, with studies showing ISBCS at or near separate surgery levels, Dr Mura added (Ganesh S et al. Indian J Ophthalmal 65(5)).
The greatest risk of ISBCS is bilateral complications that could result in visual loss in both eyes, Dr Mura noted. However, so far only four cases of bilateral simultaneous endophthalmitis have been reported, and all four failed to follow the recommended protocol established by the International Society of Bilateral Cataract Surgeons (ISBCS).
The ISBCS protocol calls for completely isolated surgeries, with nothing in contact with the first eye used for the second eye, instruments from separate sterilisation cycles, OVDs and supplies from different manufacturers or lots, separate sterile routines and independent preparation of the second eye operating field and intracameral antibiotic use. Most importantly, the complexity of the surgery should be well within the surgeon’s capabilities. This minimises the risk of systemic cross infection, Dr Mura said. At a rate of one in 5,750 individual procedures, the random risk of bilateral endophthalmitis is one in 33 million.
However, this analysis does not consider risk factors not under surgeons’ control, said Myoung Joon Kim MD, PhD, of the University of Ulsan College of Medicine, Seoul, Korea.
“The two eyes are not independent, there are risks that affect both eyes and we must think about this,” Dr Kim said.
Patient-related risks include compromised immunity, blepharitis or eye rubbing or other habits that may increase infection risk. This cannot be screened easily at the clinic, he noted.
Device-related factors such as manufacturing, cleaning or sterilisation issues could also increase systemic risk even when precautions such as using items from separate sterilisation cycles are taken, Dr Kim added. Other risks are completely unknown.
In addition, delaying the second surgery creates an opportunity to correct any refractive surprise that crops up, Dr Kim said. Even with the best biometry and lens formulas about 20% of eyes are more than 0.5 dioptres off target. Delaying the second surgery allows for compensating based on experience with the first eye, he said.
For these reasons, Dr Kim does not support routine use of ISBCS, though it may be appropriate for select patients, such as those requiring general anaesthesia.
Juan J Mura: email@example.com
Myoung Joon Kim: firstname.lastname@example.org