Robert P. Cubbidge

Visual Field Severity Indices Demonstrate Dose-Dependent Visual Loss from Vigabatrin Therapy

Purpose: The aims of this study were to develop an algorithm to accurately quantify Vigabatrin (VGB)‐induced central visual field loss and to investigate the relationship between visual field loss and maximum daily dose, cumulative dose and duration of dose.

Patients treated with vigabatrin exhibit central visual function loss.

Summary:  Purpose: To investigate visual function in the central 10 degrees in patients who have undergone vigabatrin (VGB) antiepileptic drug (AED) therapy with the aim of identifying a clinical regimen for assessing central visual function.

Drusen detection in retro-mode imaging by a scanning laser ophthalmoscope

Purpose:  The Nidek F‐10 is a scanning laser ophthalmoscope that is capable of a novel fundus imaging technique, so‐called ‘retro‐mode’ imaging. The standard method of imaging drusen in age‐related macular degeneration (AMD) is by fundus photography. The aim of the study was to assess drusen quantification using retro‐mode imaging.

The influence of learning styles, enrolment status and gender on academic performance of optometry undergraduates

Citation information: Prajapati B, Dunne M, Bartlett H & Cubbidge R. The influence of learning styles, enrolment status and gender on academic performance of optometry undergraduates. Ophthalmic Physiol Opt 2011, 31, 69–78. doi: 10.1111/j.1475‐1313.2010.00798.x

Ocular biometric correlates of ciliary muscle thickness in human myopia

Anterior segment optical coherent tomography (AS‐OCT) is used to further examine previous reports that ciliary muscle thickness (CMT) is increased in myopic eyes. With reference to temporal and nasal CMT, interrelationships between biometric and morphological characteristics of anterior and posterior segments are analysed for British‐White and British‐South‐Asian adults with and without myopia.

Altered Blood Vessel Responses in the Eye and Finger in Coronary Artery Disease

PURPOSE Cardiac function, such as heart rate variability, is abnormal in coronary artery disease, but its relation with the function of ocular and nail-fold blood vessels is unknown. The hypothesis was that there is abnormal retinal and peripheral microvascular endothelial function compared with large blood vessel and cardiac function. Twenty-four patients with coronary artery disease (CAD) and 30 healthy, age- and sex-matched control subjects were enrolled in the study. METHODS Peripheral microcirculatory function was measured with continuous retinal vessel diameter assessment and nail-fold capillaroscopy. Systemic vascular function was evaluated by 24-hour blood pressure, arterial stiffness, low (LF)- and high (HF)-frequency heart rate variability, ECG monitoring, and the plasma markers von Willebrand factor (vWf) and soluble E selectin. RESULTS Peripheral nail-fold capillary (P = 0.009) and retinal vessel (average baseline corrected flicker response [BFR]; P = 0.034) responses and reaction time in response to flicker (P = 0.016) were significantly different in patients compared with controls. Furthermore, patients demonstrated higher arterial stiffness (P = 0.005), LF and HF heart rate variability (P = 0.004, P = 0.006), and vWf level (P = 0.044), but there was no difference in soluble E selectin level (P = 0.278). In the CAD patients, LF and HF heart rate variability both correlated with average BFR (r = 0.58, P = 0.004; r = -0.6, P = 0.003, respectively). There was no such relationship in the healthy controls. CONCLUSIONS Microcirculatory abnormalities of the retina and nail-fold vessels are present in CAD. The two indices of heart rate variability correlated with an index of ocular vessel responses. The latter may be a surrogate marker of abnormal heart rate variability in CAD.

In vivo measurement of regional variation in anterior scleral resistance to Schiotz indentation

Citation information: Patel H, Gilmartin B, Cubbidge RP & Logan NS. In vivo measurement of regional variation in anterior scleral resistance to Schiotz indentation. Ophthalmic Physiol Opt 2011, 31, 437–443. doi: 10.1111/j.1475‐1313.2011.00840.x

Enhancing employability in the “ME generation”

Purpose – The purpose of this paper is to place all of the contributions to this special issue into a theoretical framework and to highlight the role that the so-called “information age mindset” has in the facilitation of employability skills. Design/methodology/approach – The paper discusses the major themes of this special issue. Findings – Undergraduate students do see the importance of technological innovation in the classroom but they see the development of experiential or work-based skills to be more important. Practical implications – Future curriculum design should consider the expectations and attitudes of the modern day undergraduate student to ensure that potential employability is maximised. Originality/value – The findings are placed into the wider context of the emerging field of evolutionary educational psychology.

Quantification of visual field loss in age-related macular degeneration.

Background An evaluation of standard automated perimetry (SAP) and short wavelength automated perimetry (SWAP) for the central 10–2 visual field test procedure in patients with age-related macular degeneration (AMD) is presented in order to determine methods of quantifying the central sensitivity loss in patients at various stages of AMD. Methods 10–2 SAP and SWAP Humphrey visual fields and stereoscopic fundus photographs were collected in 27 eyes of 27 patients with AMD and 22 eyes of 22 normal subjects. Results Mean Deviation and Pattern Standard Deviation (PSD) varied significantly with stage of disease in SAP (both p<0.001) and SWAP (both p<0.001), but post hoc analysis revealed overlap of functional values among stages. In SWAP, indices of focal loss were more sensitive to detecting differences in AMD from normal. SWAP defects were greater in depth and area than those in SAP. Central sensitivity (within 1°) changed by −3.9 and −4.9 dB per stage in SAP and SWAP, respectively. Based on defect maps, an AMD Severity Index was derived. Conclusions Global indices of focal loss were more sensitive to detecting early stage AMD from normal. The SWAP sensitivity decline with advancing stage of AMD was greater than in SAP. A new AMD Severity Index quantifies visual field defects on a continuous scale. Although not all patients are suitable for SWAP examinations, it is of value as a tool in research studies of visual loss in AMD.

Regional variability in visual field sensitivity during hypercapnia

PURPOSE Previous investigations have demonstrated a relative vascular autoregulatory inefficiency of the inferior compared to the superior retina in healthy subjects breathing increased CO(2). The purpose of this study was to determine whether the superior and inferior visual field sensitivities of healthy eyes are similarly affected during mild hypercapnia. DESIGN Experimental study. METHODS Visual field analysis (Humphrey Field Analyser; SITA standard 24-2 program) was carried out on one randomly selected eye of 22 subjects (mean age, 27.7 +/- 5 years) during normal room air breathing and isoxic hypercapnia. The Student paired t-tests were used to compare the visual field indices mean deviation (MD) and pattern standard deviation (PSD) for each breathing condition. A secondary, sectoral analysis of mean pointwise sensitivity was performed for each condition. In each case a P value of <.01 was considered statistically significant (Bonferroni corrected). RESULTS Visual field MD was -0.23 +/- 0.95dB during room air breathing and -0.49 +/- 1.04dB during hypercapnia (P =.034). Sectoral pointwise mean sensitivity deteriorated by 0.46dB (P =.006) in the upper visual hemifield during hypercapnia, whereas no significant difference was observed for the lower hemifield (P =.331). CONCLUSIONS The upper visual hemifield exhibited a significantly greater degree of deterioration in pointwise visual field mean sensitivity compared to the lower hemifield during hypercapnic conditions. This suggests that the upper visual hemifield and hence inferior retina is more susceptible to insult during hypercapnia than the superior retina in healthy individuals. A regional susceptibility of inferior retinal function to altered vascular or metabolic effects may account for the earlier and more frequent inferior nerve fibre damage associated with glaucomatous optic neuropathy.