Directional deep brain stimulation (DBS) constitutes an emerging technology that allows selective stimulation of target structures via partitioned electrode contacts. In order to effectively perform target-tailored stimulation, knowledge of the rotational orientation of the segmented leads is imperative. To develop a universally applicable and reliable method for determination of lead orientation angles in DBS using flat-panel computed tomography (fpCT). A binary template of directional leads DB-2202-30 (Boston Scientific, Natick, Massachusetts) and 6170 (Abbott, Plano, Texas) was imported into the 2-dimensional raw data set of a conventional fpCT scan. The template was aligned with and manually rotated around the predetermined lead trajectory. The overall orientation of the segmented lead can be deduced by transferring position and orientation of the lead orientation marker into the 3-dimensional volume. Accuracy of the method was investigated by two raters in a phantom study. Accuracy were 5.4°±4.1° (range: 0.4°-11.9°) for rater 1 and 5.2°±3.0° (range: 0.3°-10.2°) for rater 2, when investigating DB-2202-30. For 6170 observed deviations were 2.5°±1.7° (range: 0.2°-5.2°) and 4.3°±3.6° (range: 0.2°-11.2°) for raters 1 and 2, respectively. fpCT imaging constitutes a precise and accurate means to determine the rotational orientation of directional leads. The approach is universally transferable to different electrode designs as the template can easily be adjusted to the electrodes' specific measures. The approach is independent from polar implantation angles owing to fpCT- and methodological features.