Role of posterior keratometry in evaluating surgically-induced astigmatic change after cataract surgery

Session Details

Session Title: Presented Poster Session: Imaging Anterior Segment

Session Date/Time: Monday 07/09/2015 | 15:00-16:30

Paper Time: 15:20

Venue: Poster Village: Pod 4

First Author: : N.Reus THE NETHERLANDS

Co Author(s): :    S. Klijn   C. Van der Sommen   A. Sicam        

Abstract Details

Purpose:

To assess whether posterior keratometry has an additional value in the assessment of surgically induced astigmatic change (AC) in cataract surgery, with an emphasis on test-retest variability.

Setting:

Rotterdam Ophthalmic Institute, Rotterdam, the Netherlands.

Methods:

The study group consisted of 77 eyes of 77 cataract patients. Cataract surgery was performed through a 2.2 mm self-sealing scleral incision (n=24), single-plane clear corneal incision (SPCCI; n=29) or biplanar clear corneal incision (BPCCI; n=24). Anterior and posterior keratometry was obtained preoperatively and 6 weeks to 6 months postoperatively using a rotating Scheimpflug camera (Pentacam, Oculus). In a control group consisting of 36 eyes of 36 volunteers who did not undergo surgery, measurements were performed over a similar time interval. AC was evaluated by calculating the change polar values ΔKP(Φ) (flattening/steepening) and ΔKP(Φ+45) (torque) of the incisional meridian Φ.

Results:

With anterior keratometry, a flattening of the incisional meridian Φ of 0.37 and 0.27 D was measured in the SPCCI and BPCCI groups, respectively. This was statistically significantly different from the control group. Scleral incisions tended to produce more random AC. With posterior keratometry, changes of the incisional meridian Φ were below 0.1 D for all incisions. The changes were of the same order of magnitude as those measured in the control group.

Conclusions:

Posterior keratometry revealed that the surgically induced AC of 2.2 mm scleral and corneal incisions in cataract surgery is of negligible clinical relevance. It is of the same order of magnitude as AC that can be measured in control subjects not undergoing surgery. Thus, the role of posterior keratometry in the assessment of surgically induced AC currently is limited.

Financial Interest:

NONE