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Purpose Age‐related macular degeneration (AMD) is a major cause of vision loss. This study investigated whether performing clinical audit and receiving analytical performance feedback altered documentation of the AMD care provided by optometrists. Methods Australian optometrists were recruited and completed a survey about their demographics and confidence in AMD care, and a three‐month audit of their practice records using an AMD audit tool (termed the pre‐audit evaluation). After receiving analytical feedback, participants identified areas for improvement and re‐audited their practices after three months to analyse changes in performance (termed the post‐audit evaluation). Paired t‐tests and Wilcoxon signed‐rank tests, as appropriate, were used to compare pre‐ and post‐audit data. Results Twenty optometrists, most practising in Victoria, Australia, completed the study. Participants primarily worked in corporate practice and/or rural settings and had a range of optometric experience (2–40 years). At baseline, participants felt confident in their: knowledge of AMD risk factors (65%), advice to patients about these factors (55%) and management of earlier stages of AMD (55%). Each clinician completed (median [IQR]): 15 [IQR: 10–19] and 12 [IQR: 8–16] audits of unique patient records, pre‐ and post‐audit, respectively. Post‐audit, average record documentation (per optometrist) improved for asking about: AMD family history (94% to 100%, p = 0.03), smoking status (21% to 58%, p < 0.01), diet (11% to 29%, p < 0.01) and nutritional supplementation (20% to 51%, p < 0.01). For clinical examination, compliance with documenting pinhole visual acuity, performing an in‐office Amsler grid (upon indication) and using optical coherence tomography improved post‐audit (p < 0.05). Accuracy of severity documentation improved for earlier stages of AMD (p < 0.05). For earlier stages of AMD, documentation of counselling about modifiable risk factors significantly improved post‐audit (p < 0.05). Aspects well‐performed pre‐audit that did not change included documenting: medical histories (100% at both time points, p = 0.06) and retinal imaging (77% at both time points, p = 0.97). Conclusions Self‐audit with analytical feedback improved clinical record documentation of: AMD risk factors, clinical examination, AMD severity classification and management advice. These findings support a role for audit to improve optometric clinical care of AMD, as evidenced by improved documentation of the AMD care delivered.

Purpose Tobacco smoking and nutrition are key lifestyle factors with long-term effects on eye health. However, little is known about patients’ perceptions and experiences in these areas in relation to the care received from optometrists. The main aim was to survey patients’ perceptions and prior experience regarding the role of optometrists in enquiring and providing advice about tobacco smoking and nutrition. Methods An anonymous, paper-based survey was distributed to a convenience sample of 225 adults attending the University of Melbourne eye care clinic. Respondents provided demographic and other information (age, sex, length of time since last eye examination, country of most recent eye examination, smoking status and intake of nutritional supplements) and indicated their level of agreement (using a five-step Likert scale) with a series of statements relating to the care provided by optometrists in the areas of health, smoking and nutrition. The statements were designed to assess the perceived scope of practice of optometrists and the extent to which patients expect, and feel comfortable, discussing these issues with their optometrist. Results 220 completed surveys were returned. Most respondents (>80%) agreed that they visit their optometrist to quantify their refractive error and to examine their eye health. About two-thirds of respondents indicated that they expect their optometrist to ask about their general health, with almost half expecting their optometrist to communicate with their general medical practitioner. Approximately one-third of respondents indicated having been routinely questioned about their smoking status, diet and nutritional supplement intake by their optometrist. This was despite about half expecting their optometrist to question them about these factors and almost three out of four respondents indicating that they felt comfortable talking with their optometrist about these lifestyle behaviours. Conclusions This study provides novel insight into patients’ perceptions and experience with optometric practice in the areas of tobacco smoking and nutrition. The majority of respondents expected their optometrist to examine their eye health, ask them about their smoking and diet habits, and indicated feeling comfortable discussing these topics with their primary eye care provider. These findings suggest that brief advice interventions relating to tobacco use and diet are likely to be acceptable to deliver in optometry practice.

Dry eye disease (DED) is a common, multifactorial disease of the tears and anterior ocular surface. The clinical diagnosis of DED is complex, requiring the consideration of both patient symptoms and signs, which can be apparently contradictory. Misdiagnosis can lead to suboptimal clinical management. Studies of the practice behaviors of optometrists suggest that there is the potential to improve the translation of research evidence relating to the diagnosis of DED into primary ophthalmic care. This review describes an evidence-based, pragmatic approach to the contemporary clinical diagnosis of DED, as a means for guiding best practice for the care of dry eye patients.

Purpose: To evaluate the relation between measures of corneal power and refractive error after photorefractive keratectomy (PRK) by applying fast Fourier transform (FFT) to computerized corneal topography data. Setting: Corneal Diseases and Excimer Laser Ginic, Sunderland Eye Infirmary, Sunderland, England, and University of Dundee Department of Ophthalmology, Dundee, Scotland. Methods: Twenty-six left eyes of consecutive patients treated by PRK with a VISX Twenty-Twenty excimer laser were retrospectively analyzed. Preoperative and 3, 6, and 12 month postoperative data were studied. Changes in corneal parameters derived from corneal topography data using the FFT were compared with changes in refractive status vectors (spherical equivalent and astigmatic cosine and sine values). Result: Although highly correlated ( r 2 = 0.8839), the change in FFT-derived corneal spherical equivalent underestimated the change in refractive spherical equivalent by 25.5% over the 12 month follow-up. Decentration, measured by the 1-cycle FFT harmonic, increased significantly from a mean preoperative value of 0.12 mm ± 0.07 (SD) to 0.51 ± 0.35 mm 12 months postoperatively. Conclusions: The FFT is a powerful method for extracting clinically meaningful descriptors from corneal topography data; however, care must be taken when interpreting refractive changes from corneal data.

Purpose: To test the hypothesis that the bow-tie corneal topography pattern results from corneal asphericity in the presence of astigmatism. Methods: Astigmatic color-coded power maps using different shape factors were computer generated. Each simulation was based on the calculation of dioptric power at 20 points along each of 180 hemimeridia, for a total of 3600 points. The calculations were made independent of the capture or measurement of videokeratographs. These simulations were compared to power maps taken from clinical records. Results: A shape factor of 1.00 resulted in a spherocylinder color-coded map with straight-edged sectors of power. The familiar bow-tie pattern was generated using an elliptical model with a shape factor of less than 1.00. This pattern was reversed by modeling the cornea as an oblate ellipsoid using a shape factor greater than 1.00. Conclusions: By simple alteration of the amount of corneal asphericity through manipulation of the shape factor, computer simulation showed that this surface characteristic is responsible for the bow-tie pattern observed in corneal topography power maps.

This article reviews the optical principles of computer-assisted videokeratoscopy (CVK) and provides a guide to the differences between short and long working distance systems. The description of the corneal surface involves a number of complex issues which have yet to be adequately resolved and the importance of alignment and reference axis assumptions to CVK is discussed. With the increasing clinical use of such systems, the debate of such issues has meaning, not just in the research environment but also in routine clinical practice. A number of applications are illustrated.

Background: Graphical display of the many thousands of data points generated by corneal topography systems has progressed from three-dimensional wire representations, through curvature and power maps, to three-dimensional subtraction models. Standard colour-coded corneal ‘topographic’ maps may be misinterpreted as representing corneal profile instead of a form of corneal power. A variety of two- and three-dimensional output methods for displaying corneal topography data are demonstrated. Method: Axial colour-coded isodioptric maps were obtained with the MasterVue Ultra corneal topography system. Separate software was written to access the data files to enable construction of alternative display forms, that is, instantaneous power maps and various colour-coded three-dimensional models. Results: The relative advantages and disadvantages of various methods for viewing corneal topography measurements are demonstrated for data taken from the clinical records of two subjects. Conclusion: Newer methods for displaying corneal topography data enable the visualisation of the differences between representations of power and those of profile. The different display methods have their own advantages and limitations which make them more appropriate in certain applications and less so in others.

BACKGROUND: The clinical interpretation of corneal topography power maps has progressed through the development of both qualitative pattern classification systems and a range of quantitative descriptors. Although a number of different indices have been described, they do not all possess obvious clinical utility. METHODS/RESULTS: Fourier series analysis decomposes any circumferential fluctuations in corneal power into various components that have direct clinical correlates. The zero frequency and two-cycle components, which represent spherical equivalent and regular astigmatism, respectively, are analogous to keratometric spherical (equivalent) and astigmatic powers. The other Fourier components have no keratometric equivalent but have distinct clinical value. Decentration is a tilt of the cornea with respect to the videokeratoscope axis and irregular astigmatism is the sinusoidal variation in power that cannot be corrected with conventional lenses. CONCLUSION: The present paper demonstrates the application of Fourier series analysis to corneal topography data.

Excimer laser photorefractive keratectomy (PRK) procedures photoablate the central optical zone, potentially altering the corneal vertex normal and thus the corneal topography (CT) system reference axis. Anterior corneal surface coordinates (x, y, and z) were computer generated to simulate spherical and PRK-ablated corneal surfaces. Power maps were reconstructed by using surface tangents relative to various assumed CT reference axes, the original and displaced vertex normals. The simulation process eliminated focus, alignment, and surface-reconstruction errors. A simulated 5.00-D myopic PRK decentered 1 mm from the vertex produced a new corneal vertex 0.13 mm from the original position. Axial power-map generation by using this new reference axis produced a spherical keratectomy with astigmatic untreated periphery. This computer simulation demonstrates that reference axis changes are significant for even modest PRK decentration and can explain apparent steepening in untreated corneal areas. CT users should be aware that pre- and postoperative CT power maps may not be directly comparable.