Which statement best defines the SMV projection of the skull?

Which statement best defines the SMV projection of the skull?

• A. Projection from above the skull through the orbit.
• B. Projection from the occipital region through the vertex.
• C. Projection from below the mandible through the vertex of the skull.
• D. Projection from the chin to the foramen magnum.

Answer: (C)

SMV projection is a submentovertex radiograph. The x‑ray beam enters beneath the chin (submentum) and travels upward to exit at the vertex of the skull. This path places the base of the skull, including the foramen magnum and surrounding structures, in profile and minimizes superimposition from the facial bones, giving a clear view of the skull base and zygomatic arches. That’s why describing the projection as starting below the mandible and exiting through the vertex is the best way to define SMV. Other described paths would image different orientations and do not produce the basal skull view intended by the SMV technique.

SMV projection is a submentovertex radiograph. The x‑ray beam enters beneath the chin (submentum) and travels upward to exit at the vertex of the skull. This path places the base of the skull, including the foramen magnum and surrounding structures, in profile and minimizes superimposition from the facial bones, giving a clear view of the skull base and zygomatic arches. That’s why describing the projection as starting below the mandible and exiting through the vertex is the best way to define SMV. Other described paths would image different orientations and do not produce the basal skull view intended by the SMV technique.