Visual evoked responses, effect

Fox DA, Lewkowski JP, Copper GP. 1977. Acute and chronic effects of neonatal lead exposure on development of the visual evoked response in rats. Toxicol Appl Pharmacol 49 449-461. 

In two experimental models of ischaemia, it has been shown that HU-211 significantly increases cell survival. It was seen that after forebrain ischaemia produced by 20 min of carotid occlusion, the number of viable neurons in the hippocampal CA1 region of HU-211-treated rats was significantly higher than in controls. The same effect was seen in gerbils after 10 min of bilateral carotid occlusion on treatment with HU-211 [197, 198]. A related effect has been noted after rat optic nerve crush injury. Administration of HU-211 improved recovery of the nerve, with the visual evoked response amplitude increasing significantly [199],... 

Hosko, M.J. (1970). The effect of carbon monoxide on the visual evoked response in man. Arch. Environ. Health 21 174-80. 

Ron E, Modan B, Floro S, et al Mental function following scalp irradiation during childhood. Am J Epidemiol 116 149-160, 1982 Shore RE, Albert RE, Pasternack BS Follow-up study of patients treated by x-ray epilation for tinea capitis. Arch Environ Health 31 17-24, 1976 Yaar I, Ron E, Modan M, et al Long-term cerebral effects of small doses of x-irradiation in childhood as manifested in adult visual evoked responses. Ann Neurol 8 261-268, 1980... 

Hake and Stewart (1977) describe a study in which four male volunteers were exposed to concentrations of 0, 20, 100, and 150 ppm tetrachloroethylene for 7.5 hours/day. Exposure at each concentration lasted for 5 days. Subjective evaluation of electroencephalogiaphic scores suggested cortical depression in subjects exposed to 100 ppm. Coordination, as measured by the Flanagan coordination test, was significantly decreased at some time points during exposure to 100 or 150 ppm. No effects on flash visual-evoked responses, equilibrium tests, math skills, time discrimination, and reaction times were noted. 

Feeley, D. M., Longo, J. F., Cosden, M. A., Zenick, H. and Padich, R. (1979). Detection of the effects of lead exposure by visual evoked response latency. Physiol. Psychol., 7, 143... 

Visual evoked responses (VER) were studied in rats that had been exposed to cadmium or lead during gestation and lactation. Lead caused long-lasting changes in the VER, whereas cadmium appeared to have no definite effects in this respect unless the animals also had a low body weight or low hematocrit. ... 

Bushnell, P., Bowman, R., Allen, J. and Marlar, R. (1977) Scotopic vision deficits in young monkeys exposed to lead. Science, 196, 333-335 Feeney, D., Longo, Cosden, M., Zenick, H. and Padich, R. (1979) Detection of the effects of lead exposure by visual evoked response latency. Physiol. Psychol, 7, 143-145 Fox, D. and Sillman, A. (1979) Heavy metals affect rod, but not cone, photoreceptors. Science, 206, 78-80... 

Safety. Animal studies have shown that ranibizumab is a safe agent for intravitreal injection. In cynomolgus monkeys, intravitreal injections of 500 pg of ranibizumab at two-week intervals in a laser-induced CNV model (13) or in normal monkey eyes did not show any significant adverse effects (14). However, mild side effects of the injections were seen. All eyes treated with ranibizumab developed acute anterior chamber inflammation within 24 hours of the first intravitreal injection (13). In contrast, eyes injected with vehicle alone showed minimal or no inflammation. The inflammation resolved within one week, and the inflammatory response was less pronounced after subsequent intravitreal ranibizumab injections. Also, animal studies have shown that ranibizumab has no effect on electroretinography, including visually evoked potentials. 

An additional study did not reveal any effects on neurological function among 14 persons who lived above or next to dry cleaning facilities for 1-30 years compared to 23 controls matched for age ( 1 year, in two cases 3 and 5 years) and gender when the absolute values of the tests were examined (Altmann et al. 1995). Median tetrachloroethylene exposure concentrations were 0.2 ppm in the apartments of the exposed individuals and 0.0003 ppm in the apartments of control subjects, and blood concentrations were 17.8 46.9 pg/L in exposed individuals and less than the detection limit of 0.5 pg/L in the controls. When multivariate analysis was completed to adjust for age, gender, and education, an increased response time in a continuous performance test (p<0.05), increased simple reaction time to a visual stimuli (p<0.05), and decreased performance in a test of visual memory (p<0.05) were observed. No effect on pattern reversal visual-evoked potentials was... 

Only a limited number of chemicals evoke a local quantifiable pharmacodynamic response, for example, the concentration-dependent vasoconstriction effect of corticosteroids. In these experiments, resulting skin blanching is scored visually by one or more qualified investigators, using an ordinal data scale. The lack of instrumentation has been criticized, because of possible subjective errors [25], However, approaches using the Chromameter device, although recommended by the FDA, have failed to return the desired precision [26, 27],... 

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