Evaluation of Position-induced Cyclorotation Between Wavefront Measurement and Refractive Surgery by the Iris Registration Method

NCT ID: NCT00943163

Last Updated: 2009-07-22

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 93 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2008-01-31
• Study Completion Date: 2008-10-31

Brief Summary

Cyclorotation of eyes may be affected by motion and orientation of the head and body. An automated alignment method with the technique of iris recognition was used to assess the amount and orientation of position-induced cyclorotation between preoperative wavefront measurement and laser refractive surgery.

Detailed Description

Ninety-three consecutive patients undergoing bilateral wavefront-guided laser refractive surgery in the Department of Ophthalmology of the National Taiwan University Hospital between September 2004 and December 2007 were enrolled in this retrospective study. Before laser refractive surgery, all patients were seated in front of the Zyoptix 100 system platform (Bausch & Lomb, salt lake city, UT, USA) and received Zywave aberrometer measurement on both eyes. When patients were in the supine position for refractive surgery, an infrared camera mounted on the laser system (Technolas 217z100 excimer laser system, Bausch & Lomb)obtained iris images on undilated pupils before laser ablation. Overall cyclorotation was detected by a comparison between iris images of undilated pupils in the supine position and dilated pupils in the seated position before laser treatment. The degree and direction of position-induced cyclorotation were assessed.

Conditions

Eye Cyclorotation Degree; Pupil Shift

Study Design

• Observational Model Type: COHORT
• Study Time Perspective: RETROSPECTIVE

Eligibility Criteria

Inclusion Criteria

• patients undergoing bilateral wavefront-guided laser refractive surgery

Exclusion Criteria

• patients with strabismus, extraocular muscle palsy, muscle restriction or other diseases interfering normal ocular movement.

• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

National Taiwan University Hospital

OTHER

Sponsor Role: lead

Principal Investigators

Yu-Chih Hou, MD

Role: STUDY_DIRECTOR

Telephone: 886-2-23123456 Ext. 65025 Email: ychou51@ntu.edu.tw

Locations

Department of Ophthalmology, National Taiwan University Hospital

Taipei, , Taiwan

Countries

Taiwan

Other Identifiers

200906095R

Identifier Type: -

Identifier Source: org_study_id