Study type: Medical/biological study (experimental study)

Corneal temperature changes induced by high-field-strength MR imaging with a head coil. med./bio.

Published in: Radiology 1988; 167 (3): 809-811

Aim of study (acc. to author)

To determine changes in corneal temperature that are associated with high-field-strength magnetic resonance imaging performed with a transmit/receive head coil at local SARs exceeding the level recommended by the FDA (U.S. Food and Drug Administration).

Endpoint

Exposure

Exposure Parameters
Exposure 1: 64 MHz
Exposure duration: 2 min 40 sec.
Exposure 2: 64 MHz
Exposure duration: 8 min 40 sec

General information

MRI experiment.

Exposure 1

Main characteristics
Frequency 64 MHz
Exposure duration 2 min 40 sec.
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
SAR 2.54 mW/g minimum calculated unspecified to 3.05 W/kg.
magnetic flux density 1.5 T - - - -

Exposure 2

Main characteristics
Frequency 64 MHz
Exposure duration 8 min 40 sec
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
SAR 2.54 mW/g minimum calculated unspecified to 3.05 W/kg.
magnetic flux density 1.5 T - - - -

Reference articles

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Investigated organ system:
Time of investigation:
  • after exposure

Main outcome of study (acc. to author)

There was a statistically significant increase in the average corneal temperature (32.7°C +/- 0.7 before imaging, 33.2°C +/- 0.5 after). The changes in corneal temperature ranged from 0.0 °C to 1.8°C (mean, 0.5°C). The highest corneal temperature measured after imaging was 34.4°C. The authors conclude that clinical magnetic resonance imaging with use of a head coil at the SARs studied causes relatively minor increases in corneal temperature that do not seem to pose any thermal hazard to ocular tissue.

Study character:

Study funded by