A system for planning a pathway through an anatomical luminal network of a patient, the system comprising: a memory storing a computer program configured to analyze and manipulate CT images; a processor configured to execute the computer program; and a display device configured to display a user interface of the computer program, the user interface comprising a target selection window having a CT image window configured to display a slice of CT image data and display at least one other slice of the CT image data in response to a user input, a localizer window configured to display an image of at least one lung, the localizer window including a localizer configured to identify a cross-sectional location of the displayed slice of CT image data relative to the at least one lung, and slidably move in response to a user input made to the localizer relative to the image of the at least one lung causing the processor to sequentially update a displayed slice of CT image data in the CT image window, and a target selection element configured to display a target selection element at a location in response to a user's selection within the displayed slice of the CT image data, and select a target located at the displayed target selection element within the displayed slice of CT image data; wherein the user interface is further configured to display a target details window which overlays the target selection window, the target details window including an CT slice from each of the Axial, Coronal and Sagittal directions, each CT slice configured to display a target sizing element positioned over the target and resizable in response to a user input. a memory storing a computer program configured to analyze and manipulate CT images; a processor configured to execute the computer program; and a display device configured to display a user interface of the computer program, the user interface comprising a target selection window having a CT image window configured to display a slice of CT image data and display at least one other slice of the CT image data in response to a user input, a localizer window configured to display an image of at least one lung, the localizer window including a localizer configured to identify a cross-sectional location of the displayed slice of CT image data relative to the at least one lung, and slidably move in response to a user input made to the localizer relative to the image of the at least one lung causing the processor to sequentially update a displayed slice of CT image data in the CT image window, and a target selection element configured to display a target selection element at a location in response to a user's selection within the displayed slice of the CT image data, and select a target located at the displayed target selection element within the displayed slice of CT image data; wherein the user interface is further configured to display a target details window which overlays the target selection window, the target details window including an CT slice from each of the Axial, Coronal and Sagittal directions, each CT slice configured to display a target sizing element positioned over the target and resizable in response to a user input.