Leonore A. Engelbrecht

Straylight measurements in contact lens wear.

Purpose: (1) To quantify the effect of contact lens wear on straylight in rigid and soft contact lens wearers and (2) to relate findings to morphological changes and subjective complaints. Methods: Straylight was measured using the Oculus C-Quant during contact lens wear and after contact lens removal in 30 rigid contact lens wearers and 30 soft contact lens wearers. Semi-quantitative (0-4) slit-lamp grading of anterior segment changes using Efron grading scales and contact lens characteristics were performed. Subjects answered a straylight questionnaire. Results: Soft contact lens wearers had a mean straylight of logarithmic value of the straylight parameter [log(s)] = 0.934 during contact lens wear and after contact lens removal [comparable to log(s) = 0.938 of age-matched normal eyes]. Rigid contact lens wearers had a mean straylight during contact lens wear of log(s) = 1.167. After contact lens removal, log(s) significantly decreased to 0.997 (P < 0.01). Straylight values with rigid contact lenses were strongly increased (P < 0.001) compared with age-matched normal eyes; after contact lens removal, these values decreased but remained elevated. Straylight in rigid contact lens wearers correlated with the amount of deposits on the contact lens (P < 0.01) but not with other variables of the contact lens score. The questionnaire showed more straylight complaints in rigid contact lens wearers than in soft contact lens wearers (P < 0.01). Conclusions: Rigid contact lens wear leads to increased straylight during contact lens wear and after contact lens removal. This may be because of subclinical effects of contact lens wear on the cornea and is not seen in soft contact lens wearers.

Contributions of the Capsulorrhexis to Straylight

OBJECTIVES To quantify the effect of the capsulorrhexis on straylight and to determine optimal capsulorrhexis size. METHODS Fifty-six pseudophakic eyes with intact capsulorrhexis were included in the study. Straylight was measured with a straylight meter before and after pupil dilation. Capsulorrhexis and pupil diameter were measured and opacity of the anterior capsule was graded (on a scale of 0-5) with the slitlamp. Capsulorrhexis size and opacity were compared with the difference in straylight values between natural and dilated pupils. RESULTS The mean capsulorrhexis diameter was 4.5 mm (range, 2.9-6.2 mm). Most anterior capsular rims were opaque in the area of contact with the intraocular lens (62.5% higher than grade 1). Mean straylight before pupil dilation was log(s)=1.25 (range, 0.68-2.13), which increased to 1.46 (range, 0.88-2.22) after pupil dilation, which corresponds to a 62% increase (P <.001). The effect of capsulorrhexis size and opacity on the increase in straylight in scotopic conditions can be quantified by the following formula: Deltas = 19 x (grading of anterior capsular rim) x (fraction of pupil area covered by rhexis). CONCLUSIONS The influence of size and opacity of the capsulorrhexis via straylight is described in a quantitative model. Capsulorrhexis size must be greater than 4 mm to prevent functional problems at night.

Use of a new intra-ocular spectral domain optical coherence tomography in vitreoretinal surgery.

To describe the use of a novel intra‐ocular side‐scanning probe enabling the acquisition of spectral‐domain optical coherence tomography (SD‐OCT) images during surgery in a series of patients with complex forms of retinal detachment.

Nitinol basket-assisted pars plana vitrectomy for retained lens material removal

To evaluate the usefulness of different types of nitinol baskets to capture, lift and hold the lens material, dropped during a complicated phacoemulsification, as an adjunctive surgical tool in vitreoretinal surgery and to evaluate the outcomes and complication of this new surgical technique in a small series of patients.