Environmental and Nutritional Determinants of Macular Pigment in a Mexican Population.

Purpose: The carotenoids lutein (L), zeaxanthin (Z), and meso-zeaxanthin deposit at the macula as macular pigment (MP) and provide visual benefits and protection against macular diseases. The present study investigated MP, its nutritional and environmental determinants, and its constituent carotenoids in serum from a Mexican sample, in healthy participants and with metabolic diseases. Additionally, we compared these variables with an Irish sample. Methods: MP was measured in 215 subjects from a rural community in Mexico with dual-wavelength autofluorescence imaging reported as MP optical volume (MPOV). Dietary intake and serum concentrations of L and Z were evaluated. Results: The mean MPOV was 8429 (95% confidence interval, 8060-8797); range. 1171-15,976. The mean L and Z serum concentrations were 0.25 ± 0.15 µmol/L and 0.09 ± 0.04 µmol/L, respectively. The MPOV was positively correlated with L and Z serum concentrations (r = 0.347; P < 0.001 and r = 0.311; P < 0.001, respectively), but not with L + Z dietary estimates. Subjects with daily sunlight exposure of more than 50% were found to have significantly higher MPOV than those with less than 50% (P = 0.005). MPOV and serum concentrations of L and Z were significantly higher in the Mexican sample compared with the Irish sample, but this difference was not reflected in dietary analysis. Conclusions: These new data from a Mexican sample provide evidence of the multifactorial interactions and environmental determinants of MP such as sunlight exposure and dietary patterns. These findings will be essential for future studies in Mexico for eye health, visual function, and ocular pathology.

Perfluorocarbon-perfused vitrectomy: a new method for vitrectomy--a safety and feasibility study.

PURPOSE: To evaluate the safety and feasibility of perfluorocarbon-perfused vitrectomy (PCPV) as a technique during vitrectomy for proliferative diabetic retinopathy (PDR) and rhegmatogenous retinal detachment (RRD). METHODS: In an experimental, prospective, noncomparative and interventional study, 28 eyes of 28 patients were submitted to vitrectomy with the PCPV technique, 18 eyes with PDR and 10 with RRD. In this technique we replaced the traditional balanced saline solution (BSS) in the infusion line (conventional vitrectomy) by perfluorocarbon liquids (PCL). Some patients with PDR were treated with oxygenated PCL. Clinical evaluation, electroretinography (ERG), and endothelial cell count (ECC) were used to assess the safety of this procedure. An arbitrary grading system (grades 0-5) was used to classify the surgery and maneuvers to assess feasibility. RESULTS: No eyes had a significant decrease in ECC, and the patients in whom we could obtain ERG postoperatively showed no significant differences from preoperative ERG. In the PDR group (using oxygenated and nonoxygenated PCL), 77.8% were graded 5/5; in the RRD group 90% were 5/5. PCPV allowed better visualization of vitreous and intraocular structures, rapid retinal reattachment, less blood in the vitreous cavity, subretinal fluid resolution, blood confinement, retinal stabilization, and easier dissection of epiretinal membranes. In all cases at least one surgical step was eliminated. CONCLUSIONS: PCPV in humans is a safe and feasible technique. Probably in selected cases the use of PCL offers several advantages over BSS, because of their properties (gravitational forces, immiscibility with bodily fluids, and ability to transport oxygen). Prospective and comparative studies are necessary to establish formal indications and possible contraindications.

Vitrectomy with complete posterior hyaloid removal for ischemic central retinal vein occlusion: series of cases.

BACKGROUND: Central retinal vein occlusion (CRVO) is a common retinal vascular disorder with potentially complications: (1) persistent macular edema and (2) neovascular glaucoma. No safe treatment exists that promotes the return of lost vision. Eyes with CRVO may be predisposed to vitreous degeneration. It has been suggested that if the vitreous remains attached to the macula owing to a firm vitreomacular adhesion, the resultant vitreous traction can cause inflammation with retinal capillary dilation, leakage and subsequent edema6. The roll of vitrectomy in ischemic CRVO surgical procedures has not been evaluated. CASE PRESENTATION: This is a non comparative, prospective, longitudinal, experimental and descriptive series of cases. Ten eyes with ischemic CRVO. Vitrectomy with complete posterior hyaloid removal was performed. VA, rubeosis, intraocular pressure (IOP), and macular edema were evaluated clinically. Multifocal ERG (m-ERG), fluorescein angiography (FAG) and optic coherence tomography (OCT) were performed. Follow-up was at least 6 months. Moderate improvement of visual acuity was observed in 60% eyes and stabilized in 40%. IOP changed from 15.7 +/- 3.05 mmHg to 14.9 +/- 2.69 mmHg post-operative and macular edema from 976 +/- 196 microm to 640 +/- 191 microm to six month. The P1 wave amplitude changed from 25.46 +/- 12.4 mV to 20.54 +/- 11.2 mV. CONCLUSION: A solo PPV with posterior hyaloid removal may help to improve anatomic and functional retina conditions in some cases. These results should be considered when analyzing other surgical maneuvers.

[Association of epiretinal membranes with macular edema in pars planitis]. / Asociación de membranas epirretinianas con edema macular en pars planitis.

INTRODUCTION: Pars planitis (PP) is a form of intermediate uveitis that manifests with several posterior segment complications, including cystoid macular edema (CME) and epiretinal membrane formation (ERM). On the presence of CME the patient is usually treated with anti-inflammatory and/or immunosuppressive drugs. However the presence of CME may coexist with ERM formation, and therefore the treatment could be different. PURPOSE: To determine the association between ERM and CME in PP. MATERIALS AND METHODS: Case control series. The charts of patients diagnosed with PP were retrospectively reviewed. All patients had fluorescein angiogram (FA) and spectral domain optical coherence tomography (SD-OCT). Presence of ERM was determined by SD-OCT, while CME was determined by FA. Contingency tables were used to determine the risk of developing CME with ERM. RESULTS: 31 eyes presented ERM. 16 eyes presented CME. Relative risk to have CME and ERM was 0.971, with a P value of 0.77 (χ(2)). CONCLUSIONS: There is no association between ERM formation and the development of CME. There is no evidence to suggest a surgical approach as first line of treatment with the presence of ERM in PP.