APR 07, 2008
It is well known that a serious complication of cataract surgery is retinal detachment. Rhegmatogenous retinal detachment (RRD) occurs after phacoemulsification and extracapsular cataract extraction in up to 7.5% of cases, according to studies that followed patients for between four months and 18 years. However, the rate of RRD following cataract surgery performed by residents is unknown. The purpose of this PostScript study was to determine the RRD rate in such cases by examining the records of cataract surgery performed at two major teaching hospitals, San Francisco General Hospital (SFGH) and San Francisco Veterans Affairs Medical Center (VA), and following up with patients for 10 years.
The study found that the combined RRD rate following resident-performed cataract surgery at the two hospitals was 0.76%, which is similar to the rate reported by studies of experienced surgeons. These results are important since they allow physicians at teaching institutions to advise patients during informed consent that their risk of retinal detachment following resident-performed surgery is no greater than with surgery with a more experienced surgeon.
The study's authors identified patients who had surgery performed by residents by looking at billing codes and medical records from 1996 through 2005 and recording each patient's first subsequent RRD repair procedure through June 1, 2006. RRD patients who had experienced any of the following prior to surgery were excluded from the study: a vitreoretinal procedure, trauma, an atrophic retinal hole, hypotony, or retinal detachment.
A total of 4501 consecutive cataract surgery cases were identified, of which 4458 met the study criteria. Records indicated that RRD occurred in 34 cases: 14 at SFGH and 20 at the VA. The RRD rate was 0.69% at SFGH and 0.82% at the VA, which was not significantly different. Other complications of cataract surgery, such as vitreous loss, have been reported to be more common following surgery performed by residents; this study showed similar findings, with a rate of 6.7% in resident-performed surgery at SFGH. However, the retinal detachment rate for this hospital was not higher than that of experienced surgeons.
Drawbacks of the study included the potential for selection bias since one of the two facilities was a VA hospital that primarily treats men, and RRD risk is known to be greater in men. This was offset by the fact that the rate was statistically similar at SFGH. It was also assumed that the patients would receive subsequent treatment at the same hospital where they had undergone the cataract procedure. This may have led to an underestimation of the RRD rate since patients were lost to follow-up if they went to another facility for treatment. The study's follow-up period of 10 years may have also caused the occurrence rate to be underestimated since it is known that retinal detachment risk is elevated for many years after surgery. However, most cases do occur within the first year following surgery.