By 2020, there will be over 5,200 gigabytes of data available for every individual worldwide, she said.
Ophthalmology seems ready for Big Data as evidenced by the findings dating back to the 1990s.
Various cataract surgery databases such as the Medicare Claims Database, the Veterans Administration Hospital National Patient Care Database, and the Kaiser Permanente Northern California Database have analyzed the incidence rates of endophthalmitis after intracapsular cataract surgery and found similar annual rates ranging from 0.17% and 0.12% after extracapsular cataract surgery.
The Swedish National Cataract Surgery Register found a rate of 0.03%.
Dr. Coleman speculated that the rate of endophthalmitis in the United States is now similar.
To test this, she and her team from UCLA and the Hoskins Center for Quality Eye Care, the AAO’s qualitative care and health policy research center, analyzed outcomes from cataract surgeries performed from 2010 to 2013 in the Medicare Claims Database and from 2013 to 2014 from the Iris Registry, a longitudinal clinical data registry maintained by the AAO.
In addition to the endophthalmitis rates, the investigators also analyzed the postoperative visual acuity.
“In the Medicare Claims Database, out of about 217,000 cataract surgeries, there were 300 cases of endophthalmitis during the year, for a rate of 0.14% that was similar to the other Medicare Claims studies,” Dr. Coleman reported. “In the Iris Registry, there were 511,000 cataract surgeries with 400 cases of endophthalmitis for a rate of 0.08%.”
When the investigators evaluated the endophthalmitis rate by eye, the Iris Registry had 441 cases of endophthalmitis for an annual rate of 0.06%.
A total of 41 patients had endophthalmitis in both eyes after cataract surgery was performed in both eyes.
Dr. Coleman wanted to identify the reasons why the endophthalmitis rates differed between the Iris Registry and the Medicare Claims Database, of which the Iris Registry rates were lower.
“First, they are different patient populations. The patients in the Iris Registry were younger and the risk of endophthalmitis increases with age,” she explained.
“Second, there may have been ascertainment bias; when patients follow-up with a doctor not participating in the Iris Registry. Third, in the Medicare Claims Database it was unknown if the eye with endophthalmitis is the same eye that underwent cataract surgery.”
Regarding the visual outcomes in the Iris Registry, the preoperative Snellen acuity was an average 20/50. One month postoperatively, that improved to an average of 20/30.