Enhance visualization during cataract surgery

July 1, 2008

Visualization during cataract surgery in patients with corneal opacities can be improved using relatively simple techniques of capsular staining and dimming of the microscope light.

Key Points

"Corneal opacity limits the visualization of the anterior segment structures. The localization and intensity of the opacities are the main factors that determine the choice of a surgical technique. Treating these patients is challenging for the surgeon depending on the size and the location of the corneal opacity, with different visualization techniques possible," Dr. Akova said. She is department chair at Baskent University, Faculty of Medicine, Department of Ophthalmology, Ankara, Turkey.

1 Minimal corneal opacity with a visible iris.

2 Moderate corneal opacity with iris vessels still visible.

3 Moderate corneal opacity with the pupil margin visible but not the iris vessels.

4 Complete corneal opacity with the pupil not visible.

The mean patient age was 66 years. The etiologies of the corneal opacities included previous herpetic keratitis in 13 eyes, scarring resulting from trachoma in two eyes, and keratitis secondary to facial paralysis in one eye. The median grade of the corneal opacity was 2.8, Dr. Akova reported.

Evaluating data

The mean preoperative logMAR visual acuity was 0.9 and the mean postoperative logMAR visual acuity was 0.5. When Dr. Akova evaluated the Snellen visual acuity, she reported that the patients were subdivided into three groups.

"The patients who had the worst visual acuity preoperatively achieved 0.2 postoperatively, those with better visual acuity levels preoperatively of about 0.2 achieved from 0.5 postoperatively, and those with the best preoperative visual acuity of about 0.4 achieved 0.6 postoperatively," she reported (Figure 1).

"Patients' visual expectation and the surgeons experience determine the choice of the surgical technique. However, the possibilities must be discussed with the patient, including the need for a future keratoplasty. Recent advances in technology, such as illumination techniques and use of dye, may facilitate performing surgery under more advantageous conditions," Dr. Akova concluded.