A comparison of the potential acuity meter (PAM) and the illuminated near card (INC) in patients undergoing phacoemulsification

Determination of valid benchmarks for outcome indicators in cataract surgery: a multicenter, prospective cohort trial

OBJECTIVE

To evaluate a systematic approach to derive valid benchmarks for 2 outcome indicators intended to ascertain quality in cataract surgery and to propose benchmark levels drawn from the study results.

DESIGN

Prospective, multicenter cohort trial.

PARTICIPANTS

A total of 1685 patients (206-239 eyes per trial site) were recruited consecutively at 7 study sites. The patients featured age-related cataracts and were undergoing unilateral cataract surgery in the period between January 2007 and August 2008.

METHODS

Only patients with uncomplicated age-related cataracts were included. Cataract surgery was performed by phacoemulsification. The SN60AT (Alcon, Inc., Fort Worth, TX) intraocular lens (IOL) was used as a study lens. The IOL power was calculated using the SRK-T formula with a standardized A constant. Biometry was performed with the IOL Master (Carl Zeiss Meditex, Jena, Germany). Only highly experienced senior surgeons were involved.

MAIN OUTCOME MEASURES

The outcome indicators 1 month and 3 months after surgery were the respective achievement of: (1) maximum absolute deviation of 0.5 diopter (D) between target refraction and postoperative spherical equivalent (primary end point, refractive accuracy); (2) best-corrected visual acuity of at least 0.8 (secondary end point, visual acuity outcome).

RESULTS

In the pooled data, maximum absolute deviation of ± 0.5 D from target refraction was achieved in 80% (95% confidence interval, 78%-82%) of cases. Visual acuity of 0.8 or more was reached in 87% (95% confidence interval, 80%-93%) of cases. The results from the trial centers differed significantly in the outcomes of the primary and secondary end points (P<0.001).

CONCLUSIONS

The study quantified benchmark levels for 2 outcome indicators in a standardized cataract surgery procedure. External confounding factors such as the comorbidity of patients, which cannot be influenced by the surgeon, were excluded. The derived benchmarks selectively illustrate the quality of the surgery and are superior to success rates published in the literature from unspecific data collections. This method is more suited for improving outcome quality by benchmarking. General methodologic problems are discussed, leading to recommendations for future study designs.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Cataract surgery after pars plana vitrectomy

PURPOSE OF REVIEW

To review recent studies and advances and their possible implications in the care of patients undergoing cataract surgery after pars plana vitrectomy.

RECENT FINDINGS

Optical biometry has shown to be superior to ultrasound biometry in vitrectomized eyes but still not achieving as good results as it does in nonvitrectomized eyes. Blue light-filter intraocular lenses, with their possible advantage of macular protection, have shown no operative or functional disadvantages in vitrectomized eyes, and thus their routine use can be justified. However, presbyopia-correcting intraocular lenses, at least at their current stage of development, generally, are still not accepted for vitrectomized eyes. Combining cataract surgery with intravitreal injections of bevacizumab or triamcinolone acetonide in patients with macular edema and cataract is advisable to avoid exacerbation of the condition and improve visual outcome. Despite the recent advances, incidences of posterior capsular opacification and retinal detachment are still considerable.

SUMMARY

Understanding ocular anatomical alterations imposed by the previous pars plana vitrectomy surgery and the underlying vitreoretinal disease will allow the surgeon to address the special challenges. Despite that, recent advances in techniques and instrumentation have improved the surgical safety and outcomes, reported complications rates are still relatively high.