Background/aims Macular pigment (MP) plays an important role in visual function and in the protection of the retina from oxidative damage. It is not known whether glaucoma, a progressive neurodegenerative disease of the optic nerve, is associated with alterations in MP. This study was designed to investigate the relationship, if any, between the optical density of MP optical density (MPOD) and glaucoma.

Methods 40 subjects (23 males, 17 females) with open angle glaucoma (mean age 69 ±11), and 54 normal controls (23 males, 31 females) without ocular disease (mean age 66 ±11), visual acuity (VA) >6/18, were recruited, and underwent a comprehensive eye examination including biomicroscopy, fundoscopy, Goldmann tonometry and visual field assessment, using the 24-2 SITA-fast algorithm on the Humphrey visual field analyser (II-i Series). MPOD, at 0.5° of retinal eccentricity was determined, for all subjects, using heterochromatic flicker photometry.

Results Median (IQR) MPOD for subjects with glaucoma was 0.23 (0.42) compared to 0.36 (0.44) for controls. The difference in MPOD between the glaucoma cases and controls was statistically significant (z=−2.158, p=0.031). There was no significant correlation (p>0.05) between MPOD and disease severity.

Conclusions These findings suggest that MPOD is lower in patients with glaucoma. Further investigation is needed to determine the significance of MP in glaucoma, its relationship to glare symptoms in glaucoma and to assess what role therapeutic strategies aimed at increasing MP levels could have in the management of glaucoma.

METHODS:

MP optical density (MPOD) was measured using customized heterochromatic flicker photometry in 4373 participants. Sociodemographic and self reported health data was obtained using computer assisted personal interview (CAPI).

RESULTS

Mean (SD) MPOD for the study group was 0.203 (0.156) with a range of 0 to 1.01. MPOD was higher for participants with secondary education (mean [SD] = 0.205 [0.148]) than for those with only primary education or no education (mean [SD] = 0.183 [0.113]; P < 0.001). MPOD was also higher for those with tertiary education (mean [SD] = 0.232 [0.231]) compared with primary/no education or secondary education (P < 0.001 for both comparisons).

CONCLUSIONS:

We report that MP is lower amongst those participants of a population-representative study who did not have secondary or third level education when compared with participants who had such education. Given the emerging evidence that MP is important for visual performance and comfort, and given the putative protection that this pigment confers against AMD (especially important in the context of increased risk of AMD in this social group), public health measures aimed at improving diet for this at-risk population need to be considered.

[PubMed - indexed for MEDLINE]

Macular pigment (MP) acts as a pre-receptoral filter which selectively absorbs short wavelengths. It has the potential to alter color vision but the literature is conflicting on whether it does and, if so, to what extent, possibly reflecting differences between color mechanisms and color tests. This study was designed to identify and investigate relationships, if any, between macular pigment optical density (MPOD) and color sensitivity using a battery of techniques to quantify the color vision of color-normal observers.

Methods

Color vision was assessed with the Farnsworth-Munsell 100-Hue test (FM100), Moreland match on the HMC anomaloscope, and a customized SWAP (short wavelength automated perimetry) technique at the foveola and at 1, 2, 3, 4 and 5 degrees eccentricity. MPOD spatial profile was measured using customized heterochromatic flicker photometry.

Results

Total error scores (TES) and % partial error scores (%PES) on the FM100 were uncorrelated to MPOD. Moreland matches showed a significant long wavelength shift with MPOD at between 1 and 3 degrees (at 1.75 degrees, r= 0.489, p< .001). Sensitivities on customized SWAP (cSWAP) using foveal targets were significantly inversely correlated with MPOD at both 1.75 degrees (r = -0.461, p < .001) and 3 degrees (r = - .393, p < .001). Partial correlation analysis suggests that none of these findings can be attributed to age effects within the range 18 to 40 years.

Conclusions

Our findings suggest that dietary supplementation to increase MPOD is unlikely to adversely affect hue discrimination. The association of MPOD with cSWAP may be a temporally limited effect to which the visual system normally adapts. We suggest that cSWAP may provide a clinical tool for assessing short-wavelength foveal sensitivity.

All students enrolled at Universidade Lúrio, including the optometry students, are required to participate in the One Student One Family programme. This initiative aims to improve the public health of disadvantaged communities in Nampula province through information dissemination and increased interaction between health science students and the general public. It also provides the students with the opportunity to interact with the community and apply their theoretical knowledge in the local context. This experience will enhance their patient care and as it is a community informed project, it ensures the wider eyecare programme follows a pro-poor approach.

Aim - This paper aims to analyse the lessons learnt from the programme so far.

Methods - Surveys and key informant interviews with optometry students, individuals within communities, teaching faculty and partners involved with the Mozambique Eyecare Project will form the basis of the analysis.

Results - The results are expected to indicate both the successes and failures of the One Student One Family programme. The results will contribute to the development of a framework to improve the programme in order to achieve the desired outcome of improved community eye health.

Conclusion - The Mozambique Eyecare Project is developing human resources in Lusophone Africa through a partnership linking higher education institutions in Europe and Africa. The One Student One Family programme addresses a current deficit in eyecare knowledge within the local community by transferring knowledge from optometry students to the general public.

In conclusion, innovative models of education and interaction between students and the community is necessary to address the eye care needs of the country, the region and the continent.

Methods. Forty-seven eyes of 47 patients with nv-AMD, and corrected distance visual acuity (CDVA) logMAR 0.7 or better, undergoing intravitreal injections of ranibizumab, were enrolled into this prospective study. Visual function was assessed using a range of psychophysical tests, while mean foveal thickness (MFT) was determined by optical coherence tomography (OCT).

Results. Groupmean (±sd)MFT reduced significantly frombaseline (233±59)) to exit (205±40)) (p = 0.001). CDVA exhibited no change between baseline and exit visits (p = 0.48 and p = 0.31 resp.). Measures of visual function that did exhibit statistically significant improvements (p < 0.05 for all) included reading acuity, reading speed, mesopic and photopic contrast sensitivity (CS), mesopic and photopic glare disability (GD), and retinotopic ocular sensitivity (ROS) at all eccentricities.

Conclusion. Eyes with nv-AMD undergoing intravitreal ranibizumab injections exhibit improvements in many parameters of visual function. Outcome measures other than CDVA, such as CS, GD, and ROS, should not only be considered in the design of studies investigating nv-AMD, but also in treatment and retreatment strategies for patients with the condition.

To report changes in perceived visual functioning after surgery for symptomatic cataract with pre-operative corrected distance visual acuity [CDVA] of 0.4 logMar or better (Snellen equivalent, 20/50) and to investigate the relationship between any observed changes and preoperative physical characteristics and psycho-physical consquences of the lens opacity and any changes in psychophysical findings after the procedure.

Purpose This study was designed to investigate serum and macular response, and safety, to supplementation with meso-zeaxanthin (MZ), lutein (L) and zeaxanthin (Z), the carotenoids that constitute macular pigment (MP).

Materials and Methods 44 healthy subjects were recruited into this randomized, placebo-controlled, clinical trial. Subjects consumed one tablet per day containing 10.6 mg MZ, 5.9 mg L and 1.2 mg Z (Intervention, I group) or placebo (P group). The spatial profile of MP optical density (MPOD) was measured using heterochromatic flicker photometry (HFP), and serum concentrations of L and Z were quantified using high performance liquid chromatography (HPLC). Subjects were assessed at baseline, three and six months. Clinical pathology analysis was performed at baseline and six months.

Results Serum concentrations of L and Z increased significantly in the I group (p = 0.001 and 0.003, respectively) and remained stable in the P group (p > 0.05). There was a significant increase in central MPOD in the I group (0.25°: p = 0.001; 0.5: p = 0.001), with no significant change in the P group (p > 0.05). Clinical pathology analysis confirmed that all variables remained within the normal reference range, with the exception of total cholesterol and low density lipoprotein (LDL), which exhibited baseline values outside the accepted normal reference range prior to supplementation.

Conclusion Subjects supplemented with MZ, L and Z exhibit significant increases in serum concentrations of these carotenoids, and a subsequent increase in central MPOD. Pathology analysis suggests no adverse clinical implications of consuming these carotenoids.

Methods:  Macular pigment optical density at 0.5 retinal eccentricity was measured using two different heterochromatic flicker photometers, the MPS 9000 and the Macular Densitometer^TM, in 39 healthy subjects. Test–retest variability was evaluated separately for each instrument by taking three readings over a 1-week period in 25 subjects.

Results:  There was a moderate positive correlation for MPOD at 0.5° of retinal eccentricity between the MPS 9000 and the Macular Densitometer described by the linear equation y = 0.763x + 0.172 (r = 0.68, p < 0.001, r² = 0.46); however, a paired-samples t-test showed a significant difference in terms of mean values, with a bias of lower MPOD values being yielded by the MPS 9000 (t = −4.103, p < 0.001). Bland–Altman analysis indicated only moderate agreement between the two instruments, reflected in 95% limits of agreement of 0.1 ± 0.27. Inter-sessional repeatability, expressed as a coefficient of repeatability, ranged from 0.18 to 0.21 [mean (±SD): 0.19 (0.02)] for the MPS 9000 and from 0.11 to 0.12 [mean (±SD): 0.12 (0.01)] for the Macular Densitometer.

Conclusion:  The results demonstrate that the MPS 9000 consistently yields MPOD readings, which are lower than that found with the Macular Densitometer, and exhibits substantial test–retest variability.

Purpose

To evaluate the validity of a keratometry (K)-independent method of estimating effective lens position (ELP) before phacoemulsification cataract surgery.

Setting

Institute of Eye Surgery, Whitfield Clinic, Waterford, Ireland.

Design

Evaluation of diagnostic test or technology.

Methods

The anterior chamber diameter and corneal height in eyes scheduled for cataract surgery were measured with a rotating Scheimpflug camera. Corneal height and anterior chamber diameter were used to estimate the ELP in a K-independent method (using the SRK/T [ELP_rs] and Holladay 1 [ELP_rh] formulas).

Results

The mean ELP was calculated using the traditional (mean ELP_s 5.59 mm ± 0.52 mm [SD]; mean ELP_h 5.63 ± 0.42 mm) and K-independent (mean ELP_rs 5.55 ± 0.42 mm; mean ELP_rh ± SD 5.60 ± 0.36 mm) methods. Agreement between ELP_s and ELP_rs and between ELP_h and ELP_rh were represented by Bland-Altman plots, with mean differences (± 1.96 SD) of 0.06 ± 0.65 mm (range −0.59 to +0.71 mm; P=.08) in association with ELP_rs and −0.04 ± 0.39 mm (range −0.43 to +0.35 mm; P=.08) in association with ELP_rh. The mean absolute error for ELP_s versus ELP_rs estimation and for ELP_h versus ELP_rh estimation was 0.242 ± 0.222 mm (range 0.001 to 1.272 mm) and 0.152 ± 0.137 mm (range 0.001 to 0.814 mm), respectively.

Conclusion

This study confirms that the K-independent ELP estimation method is comparable to traditional K-dependent methods and may be useful in post-refractive surgery patients.

Research highlights

► Identifying that macular pigment significantly increased in the active group. ► Less glare disability for subjects with high macular pigment. ► Improved mesopic contrast sensitivity for subjects with high macular pigment. ► Identifying the need for further research in subjects with low macular pigment.