Related Experiment Video
Updated: May 21, 2026
05:46
Correction of Presbyopia by Monocular Bi-Aspheric Ablation Profile
Published on: September 20, 2024
Quantification of ghosting produced with presbyopic contact lens correction
Pete S Kollbaum1, BoKaye M Dietmeier, Meredith E Jansen
1Clinical Optics Research Laboratory, Indiana University School of Optometry, Bloomington, IN 47405, USA. kollbaum@indiana.edu
Eye & Contact Lens
|June 28, 2012
Summary
Patients can now quantify ghosting with multifocal contact lenses. This new questionnaire accurately measures ghost image dimensions, aiding in better visual correction assessment.
Area of Science:
- Ophthalmology
- Visual Optics
Background:
- Defocus in multifocal contact lenses creates perceived
- ghost
- images, with limited methods for quantification.
Purpose of the Study:
- Validate and implement a patient questionnaire to quantify ghost images in bifocal and multifocal contact lens wearers.
Main Methods:
- Subjects viewed simulated bifocal images with controlled ghosting dimensions (direction, offset, intensity, focus).
- Patients quantified perceived ghosting using a test card and comparison with their fellow eye.
Main Results:
- Over 95% of responses accurately matched ghosting dimensions within 1 rating unit.
- Focus was the dimension most strongly correlated with overall ghosting perception in multifocal lens wearers.
Conclusions:
- Patients can reliably report on ghost image intensity, focus, direction, and position offset.
- Well-focused ghosts are most salient perceptually, correlating with overall ghosting experience.
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