Skull Radiography Cranium Facial bones Basic Projections Cranium

Skull Radiography Cranium & Facial bones

Basic Projections Cranium l l l PA / AP PA 150 Lateral Towne’s Occipito-mental (OM) Submento-vertical Facial bones l l l Occipito-mental (OM) 300 Towne’s Submento-vertical Views for mandible

Positioning land marks

Positioning land marks Interorbital or interpupillary line Orbito-Meatal baseline (Radiographic baseline / baseline) – Line joining outer canthus of the eye to the central point of the EAM Anthropomorphic baseline (anthropological baseline) / line of Frankfurt / Reid’s baseline – line joining infra-orbital margin to the upper border of the EAM

PA (Occipito-Frontal) • Forehead and nose rests against bucky. • EAMs are equidistant from the bucky. • Baseline and median sagittal plane are right angled to the bucky. • Centre in midline at the level of EAM – perpendicular to the bucky

PA (Occipito-Frontal) Forehead and nose rests against bucky l EAMs are equidistant from the bucky l Baseline and median sagittal plane are right angled to the bucky l Cassette ; - 24 x 30 cm lengthwise l Centre in midline at the level of EAM – perpendicular to the bucky l 70 k. V, 40 m. As, 100 cm l

Radiographic Appearance - PA Criteria • Entire cranial perimeter from vertex to the mastoid process and both lateral borders. • Equal distance from the lateral border of the skull to the lateral border of the orbit on both sides. • Symmetric petrous ridges lie at the level of upper border of the orbits.