Dose-response function for lens forward light scattering after in vivo exposure to ultraviolet radiation

Michael, R.; Söderberg, Per G.; Chen, Enping

doi:10.1007/s004170050132

Cited by 32 publications

(37 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In rats, the latency period for radiation-induced (300 nm, 8 kJ/m 2 for 15 min) cataractous changes was reported to be 1 week [9]. In this study UVB (300 nm, 8 kJ/m 2 for 14.59 min) was used and the latency period was 1 week.…”

Section: Discussionmentioning

confidence: 99%

“…The radiation source for UVB was a dermatology equipment (Daavlin, Spectra 305/350, Ohio, USA) for PUVA therapy (settings; dose: 8 kJ/m 2 UVB; spectral range of the UV source: band width 290–320 nm, peak around 310 nm; skin type: 6, exposure time: 14.59 min). The UVB + melatonin group had intraperitoneal injection of melatonin (Sigma Chemical Co.) 4 mg/kg (0.1 ml/100 g) daily [7, 8]for 1 week following UVB exposure [9]. Melatonin was dissolved in ethanol with further dilution in physiological saline (final ethanol concentration, 5%).…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Effect of Melatonin on Lenticular Calcium and Magnesium in Rats Exposed to Ultraviolet Radiation

Bardak¹

2000

Ophthalmologica

View full text Add to dashboard Cite

Six-week-old rats received 8 kJ/m² ultraviolet B (UVB) for 15 min. For the intervention in cataract development, intraperitoneal injection of melatonin (4 mg/kg daily for 1 week) following UVB exposure was performed. Lenticular calcium and magnesium levels were determined in UVB + melatonin, UVB and control groups. One week after exposure, significantly more cataractous changes were observed in the UVB group than the UVB + melatonin group. The mean lens calcium and magnesium levels for the UVB group were significantly higher than those for the control and the UVB + melatonin groups. There were no significant differences between the control and the UVB + melatonin groups for the mean lens calcium and magnesium levels.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Effect of Melatonin on Lenticular Calcium and Magnesium in Rats Exposed to Ultraviolet Radiation

Bardak¹

2000

Ophthalmologica

View full text Add to dashboard Cite

show abstract

“…This procedure was repeated one more time after an interval of 4 weeks. The UVB dosage was based on the studies of Bardak et al [9] and Michael et al [10]. Waldmann 8001 K (Waldmann Lichttechnik GmbH, Schwenningen, Germany) was preferred as radiation source as it included broadband UVB wavelength.…”

Section: Methodsmentioning

confidence: 99%

Effect of Ultraviolet B Radiation on the Absorption Characteristics of Various Intraocular Lenses

Koçak

Kaynak

İlknur³

et al. 2006

Ophthalmologica

View full text Add to dashboard Cite

Background: The aim of this study was to determine the effect of ultraviolet B (UVB) exposure on UV filters of various intraocular lenses (IOLs). Methods: Eight samples each of the hydrophobic acrylic, hydrophilic acrylic and silicone IOLs were used. Four IOLs of each type was selected randomly as the control group while the remaining four IOLs of each type were exposed to a UVB dose of 1.4 J/cm² (2.40 mW/cm²) for 9.45 min, two times with a 4-week interval. IOLs were evaluated for any sign of opacification under microscope weekly. After a follow-up period of 16 weeks, spectrometry for UV filter absorption rates, scanning electron microscopy for deposit formation and energy dispersive X-ray analysis for elemental composition were performed for all IOLs, and findings of the control group IOLs were compared with those of the UVB-exposed IOLs. All these procedures were done at the Department of Ophthalmology, Faculty of Medicine, Dokuz Eylul University. Results: All the IOLs were free of any opacification during the follow-up period. Spectrometric analysis of their UV filters revealed a change in absorption rates in the hydrophilic acrylic and silicone IOLs compared to the control IOLs of the same type. Only the hydrophobic acrylic IOLs preserved the same UV absorption curve after UVB exposure. Conclusion: The pathogenesis of IOL opacification is still undetermined. Some reports claimed that the UV light was the responsible factor. Our experimental study revealed that high doses of UVB did not cause any opacification though they impaired the function of UV filters of the hydrophilic acrylic and silicone IOLs.

show abstract

“…At this angle the light cannot enter the objective aperture unless the object scatters in the forward direction. A photodiode measures light scattered to the objective aperture (Sö derberg et al 1990;Michael et al 1998a). The meter was calibrated with a lipid emulsion of Diazepam (Diazemuls, Kabi).…”

Section: Experimental Devicesmentioning

confidence: 99%

“…Also the longterm effects of repeated UVR exposure to the lens have been investigated (Wegener 1994) but, to our knowledge, this is the first study that compares the lenticular effects of different time intervals between exposures. The UVR dose applied for a single exposure in the current experiment is a near-threshold dose for cataract in rabbits and rats (Pitts et al 1977;Michael et al 1996Michael et al , 1998a). …”

mentioning

confidence: 99%

Lens opacities after repeated exposure to ultraviolet radiation

Michael¹,

Löfgren²,

Söderberg³

1999

Acta Ophthalmologica Scandinavica

Self Cite

View full text Add to dashboard Cite

ABSTRACT.Purpose: To investigate the effect of the interval between two, near-threshold exposures to ultraviolet radiation (UVR) on cataract development. Methods: One eye of Sprague-Dawley rats was exposed twice to 4 kJ/m 2 narrow band UVR (l MAX Ω300 nm) for 15 min each. The interval between exposures was 0, 6, 24 or 48 h. One week after the first exposure both lenses were removed for photography and measurement of the intensity of forward light scattering to quantify lens opacities. Results: All exposed lenses developed cataract. Forward light scattering was the same after double exposure with no interval or a 6 h interval. Forward light scattering after a 24 or 48 h interval was nearly twofold greater than that following no interval or a 6 h interval. The exposed lenses in all groups had mild anterior surface opacities and intense equatorial opacities as judged with a stereomicroscope. Conclusion: Two, near-threshold UVR exposures at 0 or a 6 h interval produce the same degree of lens opacification. When the second exposure follows 24 or 48 h after the first, lenticular damage increases. Repair processes between 24 and 48 h after exposure appear to be sensitive to UVR, and an additional exposure during this time may aggravate cataract development.

show abstract

Dose-response function for lens forward light scattering after in vivo exposure to ultraviolet radiation

Abstract: The intensity of forward light scattering in the rat lens increase exponentially with increased UVR dose between 0.1 and 14 kJ/m2.

Cited by 32 publications

References 18 publications

Effect of Melatonin on Lenticular Calcium and Magnesium in Rats Exposed to Ultraviolet Radiation

Effect of Melatonin on Lenticular Calcium and Magnesium in Rats Exposed to Ultraviolet Radiation

Effect of Ultraviolet B Radiation on the Absorption Characteristics of Various Intraocular Lenses

Lens opacities after repeated exposure to ultraviolet radiation

Contact Info

Product

Resources

About