TINGKAT PANDUAN DIAGNOSTIK LOKAL BERDASARKAN INDIKASI KLINIS PADA PEMERIKSAAN CT KEPALA

Diagnostic Reference Level (DRL) in Computed Tomography (CT) examination should be developed based on clinical indications because each clinical indication uses different scanning parameters. This study aimed to create Local DRL values based on clinical indications (DRLCIL) in Head CT examinations. A retrospective study was conducted on patients who underwent Head CT examinations with clinical indications of Hemorrhagic Stroke (HS), Non-Hemorrhagic Stroke (NHS), Space Occupying Lesion (SOL) without contrast (SOL –C), SOL with contrast (SOL + C) and trauma. The total number of patients used in this study was 745 patients, patients with clinical indications of HS 231 patients, NHS 163 patients, SOL –C 158 patients, SOL + C 67 patients, and trauma 126 patients. The local DRLCIL value was determined using the 2nd quartile value of each clinical indication. The DRLCIL values obtained for the volume weighted CT dose index (CTDIvol) and dose length product (DLP) were respectively HS (52.9 mGy; 1020.4 mGy.cm), NHS (52.9 mGy; 1046.9 mGy.cm), SOL –C (52.9 mGy; 941.1 mGy.cm), SOL +C (52.9 mGy; 1935.0 mGy.cm), and trauma (52.9 mGy; 1469.9 mGy.cm). The DRLCIL value is relatively lower (except for clinical indications of trauma) than the Indonesian Diagnostic Reference Level (I-DRL) for the type of Non-Contrast Head CT examination with the percentage difference of CTDIvol and DLP respectively being HS (–11.83%; –19.97%), NHS (–11.83%; –17.89%), SOL –C (–11.83%; –26.19%) and SOL +C compared to I-DRL Head CT with contrast (–11.83%; –22.60%). For clinical indications of trauma, the local DRLCIL value from DLP is higher than the I-DRL value, with a percentage difference of 15.29%. However, the local DRLCIL value from CTDIvol is lower, with a percentage difference of –11.83%. Local DRL has been developed at the hospital level and can be used as a recommendation for protocol optimization based on clinical indications. Keywords: X-ray, CT scan, Head CT, diagnostic reference level (DRL), local DRL from clinical indications (DRLCIL).