City Research Online

Web-based system for outcome analysis and modification in laser vision correction

Zuberbuhler, B (2010). Web-based system for outcome analysis and modification in laser vision correction. (Unpublished Doctoral thesis, City, University of London)


Refractive laser eye surgery is a specialised field in ophthalmology which aims to correct the refractive disorder of an eye. The most established technique is LASIK, which has shown good results for the treatment of simple myopia. Complex refractive disorders, such as compound myopic astigmatism, have shown less predictable refractive outcomes, and in some cases the severe over- or under-correction can even worsen the preoperative situation and damage the eye.

In its first stage, this research aimed to develop a software system able to present and analyse refractive outcomes. Over 2 prototype stages, this research has led to an operational system named IBRA (Internet Based Refractive Analysis), offering web-based data collection and refractive and vector analysis.

In a second stage, Nomogram calculation formulas were developed and integrated into IBRA. These formulas were created from linear regression and best-fit analyses of spherical and cylindrical outcome data stored in IBRA. The purpose of the nomogram calculations was to provide surgeons with adjustment factors that could be used to improve the refractive outcome of patients with complex refractive disorders.

Two extensive clinical audits and a randomized controlled trial were performed at Moorfields Eye Hospital to evaluate the IBRA nomogram adjustments. This research showed that IBRA was able to achieve a positive health change. In addition, results from the audits and trial contributed to the knowledge of nomogram adjustments and provided a framework in which future investigations on nomogram and treatment modifications could be performed.

In addition to the above clinical studies, two evaluations were performed with the use of IBRA and data logging techniques to investigate users‟ behaviour relating to the management of data entry processes and the use of analysis functions. This research revealed the best method for entering refractive data, and was able to identify the most important analysis methods.

Finally, the use of IBRA and its user-interface were investigated with a user satisfaction survey. The results from this questionnaire based study showed a high acceptance of the web-based platform of IBRA and indicated points for improvement (Documentation).

Publication Type: Thesis (Doctoral)
Subjects: R Medicine
R Medicine > RE Ophthalmology
Departments: School of Health & Psychological Sciences
Doctoral Theses
School of Health & Psychological Sciences > School of Health & Psychological Sciences Doctoral Theses
Text - Accepted Version
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