The effect of intracameral anesthesia on macular thickness and ganglion cell-inner plexiform layer thickness after uneventful phacoemulsification surgery: prospective and randomized controlled trial.

BACKGROUND: To evaluate the effect of intracameral lidocaine anesthesia on macular thickness and macular ganglion cell-inner plexiform layer (GC-IPL) thickness following uneventful phacoemusification in healthy subjects. METHODS: This is a prospective, randomized and double- masked study. One hundred eyes of 74 consecutive patients were randomized to receive intracameral preservative-free lidocaine 1 % (intracameral lidocaine group) or intracameral injection of balanced salt solution (sham injection group) at the time of the phacoemulsification surgery. Preoperative and postoperative macular thickness analyses with spectral domain optical coherence tomography (SD-ODT) were performed and the results between the two groups were compared. RESULTS: Postoperatively, both the central foveal thickness (CFT) and the thickness of perifoveal macula were significantly improved in both groups (p < 0.001). There was no statistically significant difference between CFT and the inner and outer macular zone thicknesses of the two groups at any follow-up time. In both groups, GC-IPL thickness was significantly increased at the first week and first month visits (p < 0.001). There was no statistically significant difference between GC-IPL thickness measurements of the two groups at any follow-up time. CONCLUSION: The current study demonstrated that supplementary intracameral lidocaine 1 % did not cause more macular thickening than the intracameral sham injection during a follow-up period of 3 months. The present study also showed a tendency for a transient increase in high definition SD-OCT-based GC-IPL thickness measurements within a few months following cataract surgery under both intracameral lidocaine anesthesia and intracameral sham injection.

Evidence for macular gravity receptor modulation of hypothalamic, limbic and autonomic nuclei.

Mice lacking normal vestibular gravity reception show altered homeostatic, circadian and autonomic responses to hypergravity (+G) exposure. Using c-Fos as a marker of neuronal activation, the current study identifies CNS nuclei that may be critical for initiating and integrating such responses to changes in vestibular signaling. This experiment utilized the mutant C57BL/6JEi-het mouse (het), which lacks macular otoconia and thus gravity receptor function. Following 2 h of 2G (2x Earth's gravity) exposure (via centrifugation) the neuronal responses of the het mice were compared with wildtype mice similarly exposed to 2G, as well as het and wildtype 1G controls. Wildtype mice exposed to 2G demonstrated robust c-Fos expression in multiple autonomic, hypothalamic and limbic nuclei, including: the lateral septum, bed nucleus of the stria terminalis, amygdala, paraventricular hypothalamus, dorsomedial hypothalamus, arcuate, suprachiasmatic hypothalamus, intergeniculate leaflet, dorsal raphe, parabrachial and locus coeruleus. The het mice exposed to 2G demonstrated little to null c-Fos expression in these nuclei with a few exceptions and, in general, a similar pattern of c-Fos to 1G controls. Data from this study further support the existence of a complex and extensive influence of the neurovestibular system on homeostatic, circadian and possibly autonomic regulatory systems.

Decreased carotenoid concentrations due to dietary sucrose polyesters do not affect possible markers of disease risk in humans.

Excessive consumption of energy and fat increases the risk for obesity. Snacks containing sucrose polyesters (SPE) as a dietary fat replacer are on the market in the United States. SPE products have been shown to lower concentrations of serum carotenoids in short-term studies. Experimental studies on the longer-term effects on health of decreased carotenoid concentrations are lacking. A 1-y randomized, double-blind, placebo-controlled parallel trial was performed. Subjects (n = 380) with a habitual low or high fruit and vegetable intake were assigned to the treatments (0, 7, 10 or 17 g/d SPE). SPE was given in the form of spreads, chips or both. The groups were compared for serum carotenoids, vitamins and markers of oxidative damage, eye health, cardiovascular health and immune status. After 1 y, serum lipid-adjusted carotenoids showed the largest decrease in the SPE chips and spread group (17 g/d) compared with the control group [alpha-carotene 33%; beta-carotene 31%, lycopene 24%, beta-cryptoxanthin 18%, lutein 18% (all P < 0.001) and zeaxanthin 13% (P < 0.05)]. Consumption of SPE spread (10 g/d SPE) decreased carotenoid concentrations by 11-29% (all P < 0.05). SPE chips (7 g/d SPE) decreased zeaxanthin (11%), beta-carotene (12%) and alpha-carotene (21%; all P < 0.05). Serum lipid adjusted alpha-tocopherol decreased significantly by 6-8% (all P < 0.001) in all SPE groups. No negative effects were observed on markers of oxidation, eye health, cardiovascular health or immune status. This study shows that decreases in serum carotenoid concentrations do not affect possible markers of disease risk.