CT NEURO PROCEDURES

• The patient’s head is positioned in the head holder for most protocols of the head.
• When the head holder is not used, a molded sponge is placed directly on the scan table and the patient’s head is positioned within the sponge
• The slice angle is determined by the position of the patient’s head (i.e., moving the chin up or down) and the angle of the gantry.
• using the supraorbital meatal line (also called the glabellomeatal line) to reduce radiation exposure to the lens of the eye
• axial (step and-shoot) techniques are often used for routine brain imaging
• the helical CT mode is used mainly for the purpose of generating three- dimensional reformations or to minimize motion-related artifacts.
• For most applications concerning structural imaging of the brain and skull base, nonenhanced CT is usually adequate.
• Routine scanning of the neck is typically performed with the patient supine and the neck slightly extended. It is most often performed in the helical mode.
• The split bolus injection technique is also frequently used for maxillofacial studies in which contrast media is indicated
• In neck protocols, the total contrast dose is often split in half
• CT angiography has the advantages of being noninvasive and widely available
• CT examinations of the spine produce images with inherently high soft tissue contrast. T
• Proper localization is essential in scanning the spine.
• Thoracic spine DFOV

  ~16cm
• IV contrast for CTA Spine

  120 mL at 6mL/s. Scan delay= tracking bolus
• Window settings for CTA- COW Carotid

  90ww/ 35wl (vertex)

  140 ww/ 40 wl (posterior fossa)

  250 ww/ 30wl (foramen magnum)
• Window settings for CTV, Neck, cervical, thoracic, lumbar spine, and CTA spine

  350ww/ 50wl
• IV contrast for orbits

  100 mL at 1.0 mL/s. Split bolus - Two 50mL injection. 2 min. delay
• IV contrast for sella

  150 mL at 1.0 mL/s. Scan delay: 75s
• IV CONTRAST FOR CTA-COW

  60 ml at 4.0 mL/s; 20 ml at 4.0 ml/s. Scan delay= from timing bolus (use carotid artery at ~ level of c4 for ROI
• IV contrast for Neck

  125 mL at 1.5 mL/s: Split bolus 1st inject 50 mL, 2 minute delay, 75 ml for 2nd; 25s scan initiated
• DFOV for Trauma facial bones

  18 cm
• DFOV for neck

  18 cm
• DFOV for brain perfusion

  25 cm
• DFOV for cervical spine

  ~13
• DFOV for CTA spine

  20
• DFOV for Thoracic spine

  ~16
• DFOV for lumbar spine

  14-16
• IV contrast for brain perfusion

  50 mL (370 concentration) at 4.0 mL; 20 saline flush mL at 4.0 mL/s- 5s delay
• IV contrast for CTA-Carotid

  80 ml at 4.0ml/s ;40 at 4.0ml/s=scan delay= from timing bolus