Critique of the Cervical & Thoracic Vertebrae Chapter 7 Cervical Vertebrae (AP) Contrast & density: demonstrate soft tissue, air filled trachea, & bony structures Good penetration: shows T & C of vertebral bodies, uncinate processes, spinous processes, and anterior tubercles 75 to 80 kVp with grid Control patient motion, stop breathing, & short OID Cervical Vertebrae (AP) ? True AP ?spinous processes aligned with midline of cervical bodies, mandibular angles, and mastoid tips are equal distances from c-spine ?articular pillars and pedicles symmetric and seen lateral to c-bodies ?distances from vertebral column to medial (sternal) ends of clavicles equal Cervical Vertebrae (AP) Rotation is present if: 1) mandibular angles and mastoid tips are not seen at equal distances from the C-vertebrae 2) spinous processes are not seen in midline of Cbodies 3)pedicles & articular pillars are not symmetrically seen lateral to vertebral bodies 4) medial ends of clavicles are not seen at equal distances from vertebral column ** For trauma, remember what to do! Cervical Vertebrae (AP) ?intervertebral disk spaces open ?vertebral bodies seen without distortion ?each vertebral spinous process is seen at the level of it inferior intervertebral disk space ?lordotic curvature ? Central ray angled to open disk spaces and undistorted vertebral bodies AP erect- 20 degree cephalad AP supine- 15 degree cephalad ( due to lordotic curvature is straightened when supine) Cervical Vertebrae ( AP) ? All of 3rd cervical vertebrae seen, and posterior occiput & mandibular mentum superimposed ?long axis of cervical column aligned ?5th cervical vertebra in center of field, showing 3rd – 7th c-vertebrae with 1st thoracic vertebra on film ?acanthiomeatal line (imaginary line from upper lip, and below nose to external ear opening) perpendicular to tabletop or upright grid Cervical Vertebrae (AP- Atlas & Axis) Open Mouth Position No preventable artifacts (dentures, hairpins) Good penetration – see atlas’s lateral masses & transverse processes & the axis’s dens spinous process & body (70 to 80 kVp) ?true AP – atlas is symmetrically seated on axis with atlas’ lateral masses at equal distances from dens. Spinous process of axis aligned with midline of axis’s body, mandibular rami seen at equal distances from lateral masses Cervical Vertebrae –(AP Atlas & Axis) Determine rotation by judging the distance between the mandibular rami and the lateral masses. Side showing greater distance is side the face is rotated toward ?upper incisors & posterior occiput’s inferior edge seen superior to the dens & atlantoaxial joint ?atlantoaxial joint open & axis’s spinous process seen in midline and inferior to dens ?dens centered in field Cervical Vertebrae (lateral) 75 to 80 kVp- see air filled trachea, prevertebral fat stripe (in front of anterior surfaces of vertebrae) abnormal widening of the space between these two detects ?fractures, masses, and inflammation Grid is optional due to long OID (air gap technique) 72 inch SID to reduce magnification Cervical Vertebrae (lateral) ? True lateral: rt & lt sides of each cervical vertebrae are superimposed, showing the spinous processes and vertebral bodies in profile. To prevent rotation superipose the patient’s shoulders, mastoid tips, & mandibular rami. 3 goals: alignment of the cervical vertebral column parallel with film, demonstration of C1 and C2 without occiput or mandibular superimposition, and superimposition of the anterior, posterior,superior, and inferior aspects of the cranial and mandibular cortices Cervical Vertebrae (lateral) ?long axis of cervical vertebral column aligned with long axis Extension & flexion films are for anteroposterior vertebral mobility ?C-4 in center of field Use weights, pull down on recumbent patients or do swimmer’s view Cervical Vertebrae ( Anterior & posterior obliques) Anterior oblique places the intervertebral foramina of interest closer to the film Posterior oblique places the intervertebral foramina of interest farther from the film. ? Cervical vertebrae rotated 45 degrees ?not rotated enough: intervertebral foramina are narrowed or obscured, pedicles are foreshortened & vertebral column are superimposed Cervical Vertebrae (Anterior & posterior obliques) ? Rotated too much: one side of pedicles partially foreshortened, but other side is aligned with midline of vertebral bodies & zygapophyseal joints shown without vertebral body superimposition are open ?cranium in lateral position ? Long axis of cervical vertebral column aligned ?C5 in center of field CervicoThoracic vertebrae (Swimmer’s lateral position) 80 to 90 kVp ?cervicothoracic vertebrae in a true lateral position ?intervertebral disk spaces open & vertebral bodies shown without distortion ?long axis of cervicothoracic column aligned with long axis of film ?T 1 in center of field (C5-C7 with T 1,2, &3 ?if needed a 5 degree caudal central ray angle can be used. Thoracic Vertebrae ( AP) 75 to 85 kVp ?use wedge or anode heel effect Expiration exposure decreases the thoracic cavity’s radiographic density by reducing the air volume and compressing the tissue in this area. This allows us to see posterior ribs and mediastinum region better ?true lateral thoracic vertebral ?intervertebral disk spaces open & vertebral bodies seen without distortion For kyphotic patients do erect ?long axis of thoracic aligned with T7 in center of field Thoracic Vertebrae (lateral) 80 to 90 kVp Due to lungs & axillary ribs, use breathing technique: long exposure time(3 to 4 seconds) and ask patient to breathe shallowly and steady, upward and outward movement of ribs and lungs. This causes blurring of ribs and lung markings resulting in greater thoracic vertebral visualization ?true lateral thoracic vertebrae ?intervertebral disk spaces open and vertebral bodies shown without distortion ?long axis aligned ?T7 in center of field ?T 12 on film, follow last rib