Optimizing landmark selection in head CT: Impact on eye radiation dose and diagnostic quality

Head CT is the most frequent examination in every hospital in Indonesia. Radiation protection on Head CT is important because of the existence of sensitive organ that is eyes.The present study investigated the impact of different cranial baselines on image quality and lens radiation dose in head CT. Diagnostic information was evaluated in six cases, three scanned using the OML and three with the SOML baseline, and subsequently reviewed by three radiologists through a structured questionnaire. Ocular radiation dose was measured in ten additional cases, five per variation, using TLD-100 dosimeters placed on the eyelid. Measured values were compared with the reference provided in ICRP Publication 87 (2000). The findings showed no significant difference in image information between the SOML and OML orientations, as indicated by the T-test result with a p-value of 0.7419. A substantial reduction in radiation dose was observed when using the SOML baseline (6.411-8.747 mGy) compared with the OML baseline (50.729-70.952 mGy). For head CT examinations, it is recommended that the scanogram be aligned parallel to the SOML, as this orientation provides greater protection for the eyes.