Purpose To develop an application for the Pentacam HR for the purpose of optimising the accuracy of the diagnosis of progressive keratoconus. Methods Measurements were performed on one randomised eye in twenty-five subjects with keratoconus Stage 1-2 according to the Amsler-Krumeich classification on two occasions, three days apart. Four replicate measurements were made by a single examiner on each occasion. The inter-day repeatability and detection limits for the diagnosis of progressive keratoconus were calculated for the following parameters: K2 and Kmax, and the parameters A, B and C from the Belin ABCD Progression Display. The measurements used as input are automatically extracted from the Pentacam HR database as comma-separated values. The application, developed in the R programming environment, provides a web browser-based user interface that presents these parameters both numerically and graphically. Results The application includes detection limits for the diagnosis of progressive keratoconus obtained from two previous studies on the inter-day repeatability of measurements in subjects with keratoconus. The detection limits are based on inter-day repeatability, stratified according to disease severity, allowing the comparison of single measurements or a mean of four replicates. Conclusions This is the first application to provide an assessment of progressive keratoconus using detection limits based on inter-day repeatability. We believe this application will contribute to the more accurate diagnosis of progressive keratoconus. It also facilitates diagnosis and improves the clinical workflow as all the relevant information is presented numerically, graphically, and colour-coded in one interface.

PurposeAutomated perimetry provides a standardized method of measuring the visual field. The Humphrey Field Analyser (HFA) uses the 24‐2 test pattern to cover 24 degrees centrally or the 30‐2 test pattern to cover a slightly broader region of 30 degrees. The aim of this study was to determine whether the 24‐2 test pattern provides comparable information to the 30‐2 test pattern in detecting visual field defects in patients with tumours in the pituitary region.MethodsA retrospective cohort study was carried out on patients with tumours in the pituitary region and radiologically confirmed compression of the visual pathway. Included patients (79 of 133) had been examined using the Humphrey 30‐2 visual field test, after which the 30‐2 test patterns were reduced into corresponding 24‐2 test patterns. The location of visual field defects, visual acuity and the perimetric parameters mean deviation (MD) and visual field index (VFI) were also recorded.ResultsNo patient was classified differently when evaluated with the 24‐2 test pattern, compared to the 30‐2 test pattern. Interestingly, although the majority of patients had visual field defects located in the temporal visual field of each eye, a significant minority did not. In addition, it was found that a large proportion of patients had normal visual acuity (≥0.8).ConclusionsThe use of the HFA 24‐2 test pattern reliably detected visual field defects in patients with tumours in the pituitary region. The present study indicates that MD and VFI are not reliable parameters for evaluating visual field defects due to compression.