New research on surgery volumes for cataract operations
GOTHENBURG, Sweden: In general, surgeons who perform numerous cataract operations each year encounter relatively few severe cases, which probably contributes to their lower complication rate, as shown by a study led by the University of Gothenburg. The study results have provided new evidence in the endeavour to further improve patient care.
During cataract surgery the cloudy lens in the patient’s eye is replaced by an implanted artificial intraocular lens made of plastic. Data from the Swedish National Cataract Register enabled the researchers to analyse surgical outcomes in the years from 2007 to 2016 at an individual level—that is, for each surgeon. Although the surgeons’ identities were coded, the results provided new knowledge and understanding.
A previous study showed that surgeons who performed 500 or more cataract operations per year achieved the best results in terms of an established quality measure: the proportion of patients suffering the complication known as posterior capsule rupture.
Higher proportion of simple cases
In the current study the researchers proceeded to investigate how much case mix—that is, how many cases of a more severe nature are treated by individual surgeons—affects the outcome. “We saw that although the high-volume surgeons, too, had severe surgical cases, that proportion was lower than for the other surgeons. So, an overwhelming proportion of the high-volume surgeons’ operations were simple cases, which may contribute to their lower incidence of complications,” said lead-author Prof. Madeleine Zetterberg from the department of clinical neuroscience at the University of Gothenburg.
Accessible and safe for patients
“Surgeons need to be aware of how operation volumes affect outcomes. A cataract operation is mostly a routine intervention, and the complication rate is generally low. But it’s important to remember that complications do occur and they may be serious,” explained Zetterberg.
Since 2015, a majority of cataract procedures in Sweden are being performed at private clinics, to which the work is outsourced by the regional authorities to meet the high level of needs. In a following study, Zetterberg will look more closely at the role of the type of clinical unit—whether under private or public management—in terms of operation volume, incidence of complications and degree of severity among the cases dealt with.
“This is vital information for us to learn how best to shape healthcare so as to ensure both high accessibility and good patient safety,” she concluded.
The study titled “A composite risk score for capsule complications based on data from the Swedish National Cataract Register: Relation to surgery volumes” was published online on 22 July 2020 in Ophthalmology.