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Background To determine the agreement between intraocular pressure (IOP) measurements using conventional Goldmann applanation tonometry (GAT) and SUOER SW-500 Rebound Tonometer. Methods This was a prospective observational study where 205 eyes of 106 glaucoma patients had their IOPs measured by 2 fellowship trained ophthalmologists. Data were analysed using the Bland-Altman method of differences. Correlation was measured using the Pearson coefficient. Results Most of our patients were Chinese (88.7%) and female (51.9%). The average age was 66.9 years. The range of IOPs as measured by GAT was 2 to 58 mm Hg. Using the Bland-Altman method to compare GAT and SUOER SW-500 Rebound Tonometer. The tonometer overestimated the IOP by 0.5mm Hg in the right eye and underestimated it by 0.1 mm Hg in the left eye. The Tonometer IOP correlated well with GAT, with a Pearson coefficient of correlation(r) of 0.89 (P < 0.001) for the right eye and 0.86 (P < 0.001) for the left eye, respectively. In patients with GAT IOP ≥ 21 mm Hg (n = 25), the Tonometer underestimated the IOP by 2.96 mm Hg. Conclusions The IOP measurements from the SUOER SW-500 Rebound Tonometer correlates with the conventional GAT in measuring the IOP. SUOER SW-500 Rebound Tonometer may be of use, especially if the risk of transmission of infection is high considering that the probes are disposable. It is easy to use and its small size and portability makes it useful in situations where the patient is unable to be examined at the slit lamp.

Objectives To report the processes used to design and implement an assessment tool to inform funding decisions for competing health innovations in a tertiary hospital. Methods We designed an assessment tool for health innovation proposals with three components: “value to the institution,” “novelty,” and “potential for adoption and scaling.” The “value to the institution” component consisted of twelve weighted value attributes identified from the host institution’s annual report; weights were allocated based on a survey of the hospital’s leaders. The second and third components consisted of open-ended questions on “novelty” and “barriers to implementation” to support further dialogue. Purposive literature review was performed independently by two researchers for each assessment. The assessment tool was piloted during an institutional health innovation funding cycle. Results We used 17 days to evaluate ten proposals. The completed assessments were shared with an independent group of panellists, who selected five projects for funding. Proposals with the lowest scores for “value to the institution” had less perceived impact on the patient-related value attributes of “access,” “patient centeredness,” “health outcomes,” “prevention,” and “safety.” Similar innovations were reported in literature in seven proposals; potential barriers to implementation were identified in six proposals. We included a worked example to illustrate the assessment process. Conclusions We developed an assessment tool that is aligned with local institutional priorities. Our tool can augment the decision-making process when funding health innovation projects. The tool can be adapted by others facing similar challenges of trying to choose the best health innovations to fund.

PurposeTo study the associations between optic nerve head (ONH) strains under intraocular pressure (IOP) elevation with retinal sensitivity in glaucoma subjects.DesignClinic based cross-sectional study.Participants229 subjects with primary open angle glaucoma (subdivided into 115 high tension glaucoma (HTG) subjects and 114 normal tension glaucoma (NTG) subjects).MethodsFor one eye of each subject, we imaged the ONH using spectral-domain optical coherence tomography (OCT) under the following conditions: (1) primary gaze and (2) primary gaze with acute IOP elevation (to approximately 33 mmHg) achieved through ophthalmodynamometry. A 3-dimensional (3D) strain-mapping algorithm was applied to quantify IOP-induced ONH tissue strain (i.e. deformation) in each ONH. Strains in the pre-lamina tissue (PLT)and the retina, the choroid, the sclera and the lamina cribrosa (LC) were associated (using linear regression) with measures of retinal sensitivity from the 24-2 Humphrey visual field test (Carl Zeiss Meditec, Dublin, CA, USA). This was done globally, then locally according to the regionalization scheme of Garway-Heath et al.Main Outcome MeasuresAssociations between ONH strains and values of retinal sensitivity from visual field testing.ResultsFor HTG subjects, we found that (1) there were significant negative linear associations between ONH strains and retinal sensitivity (p(2) high strain regions co-localized with anatomically-mapped regions of high visual field loss, (3) the strongest negative associations were observed in the superior region and in the PLT. In contrast, for NTG subjects, no significant associations between strains and retinal sensitivity were observed except in the supero-temporal region of the LC.ConclusionWe found significant negative associations between IOP-induced ONH strains and retinal sensitivity in a relatively large glaucoma cohort. Specifically, HTG subjects who experienced higher ONH strains were more likely to exhibit lower retinal sensitivities. Interestingly, this trend was in general less pronounced in NTG subjects, which could suggest a distinct pathophysiology between the two glaucoma subtypes.

To assess whether the 3-dimensional (3D) structural configuration of the central retinal vessel trunk and its branches (CRVTB) could be used as a diagnostic marker for glaucoma.Retrospective, deep-learning approach diagnosis study.We trained a deep learning network to automatically segment the CRVTB from the B-scans of the optical coherence tomography (OCT) volume of the optic nerve head. Subsequently, 2 different approaches were used for glaucoma diagnosis using the structural configuration of the CRVTB as extracted from the OCT volumes. In the first approach, we aimed to provide a diagnosis using only 3D convolutional neural networks and the 3D structure of the CRVTB. For the second approach, we projected the 3D structure of the CRVTB orthographically onto sagittal, frontal, and transverse planes to obtain 3 two-dimensional (2D) images, and then a 2D convolutional neural network was used for diagnosis. The segmentation accuracy was evaluated using the Dice coefficient, whereas the diagnostic accuracy was assessed using the area under the receiver operating characteristic curves (AUCs). The diagnostic performance of the CRVTB was also compared with that of retinal nerve fiber layer (RNFL) thickness (calculated in the same cohorts).Our segmentation network was able to efficiently segment retinal blood vessels from OCT scans. On a test set, we achieved a Dice coefficient of 0.81 ± 0.07. The 3D and 2D diagnostic networks were able to differentiate glaucoma from nonglaucoma subjects with accuracies of 82.7% and 83.3%, respectively. The corresponding AUCs for the CRVTB were 0.89 and 0.90, higher than those obtained with RNFL thickness alone (AUCs ranging from 0.74 to 0.80).Our work demonstrated that the diagnostic power of the CRVTB is superior to that of a gold-standard glaucoma parameter, that is, RNFL thickness. Our work also suggested that the major retinal blood vessels form a "skeleton"-the configuration of which may be representative of major optic nerve head structural changes as typically observed with the development and progression of glaucoma.