Microwave-induced cataracts of the eye lens: strategies for modeling and prevention in vitro and in vivo. Annual summary report, December 1983-December 1984

Technical Report · Sat Dec 01 04:00:00 EST 1984

OSTI ID:6856946

Trevithick, J R

Rat ocular lenses were studied after fixation and critical point drying of the tissue by scanning electron microscopy (SEM) following exposures to elevated temperatures and/or microwave irradiation in a thermostatically controlled chamber. In this way, the temperature of the lens bathing medium was set independently of the temperature increase normally associated with application of microwave power. Irradiations were done at 37 C and many specific absorption rates (SAR) for three durations. These were accomplished at 915 MHz in WR975 waveguide with either pulsed (Pu) or continuous wave (CW) radiation of equal average power. The parameters of the (Pu) radiation were selected to maximize the production of thermoacoustic expansion. Depth of damage caused by pulsed (Pu) and continuous wave (CW) microwaves was estimated by scanning electron microscopy in rat lenses fixed immediately after irradiation in vitro in circulating thermostatically-controlled buffered saline. Pulses of 10-sec width of 24-kW peak power were delivered to the lens at different repetition rates in order to permit the same total energy to be delivered during 6, 20, or 60 minutes of irradiation. For both models, the pulsed irradiation mode produced 4.7 times the depth of damage caused by CW irradiation. These results are discussed in relation to previous Pu-CW comparisons. It is proposed that this additional damage at the same average power is caused by thermoelastic expansion (TEE).

• Research Organization: University of Western Ontario, London (Canada). Dept. of Biochemistry
• OSTI ID: 6856946
• Report Number(s): AD-A-177087/4/XAB
• Country of Publication: United States
• Language: English

Related Subjects

560400* -- Other Environmental Pollutant Effects
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BODY
BODY AREAS
CATARACTS
CONTROL
DISEASES
DRYING
ELASTICITY
ELECTROMAGNETIC RADIATION
ELECTRON MICROSCOPY
EYES
FACE
FREQUENCY RANGE
HEAD
IRRADIATION
MECHANICAL PROPERTIES
MEDIUM TEMPERATURE
MHZ RANGE
MHZ RANGE 100-1000
MICROSCOPY
MICROWAVE RADIATION
ORGANS
PULSES
RADIATION EFFECTS
RADIATIONS
RADIOINDUCTION
SENSE ORGANS
SENSE ORGANS DISEASES
TENSILE PROPERTIES
THERMOELASTICITY