What is a key characteristic of a correctly positioned lateral skull image?

A correctly positioned lateral skull image requires the midsagittal plane to be parallel to the image receptor (IR). When the midsagittal plane is parallel to the IR, it ensures that the structures of the skull are accurately represented, allowing for an optimal view of both sides of the skull. This alignment is essential to produce a symmetric image where both the right and left sides of the skull can be properly assessed.

In a lateral skull projection, the goal is to visualize the entire skull in profile, which includes distinct anatomical landmarks such as the orbital, zygomatic, and temporal bones. This positioning ensures that these structures are not distorted and appear clear on the radiograph. Proper alignment also helps in evaluating any potential pathologies or fractures.

Other options presented do not meet the criteria for an accurate lateral skull image. For example, angling the central ray or making incorrect adjustments to the infraorbitomeatal line can lead to misrepresentation or poor visualization of cranial structures. Thus, having the midsagittal plane parallel to the IR is a fundamental principle in achieving a high-quality lateral skull image.