CT TECHNIQUE FOR BRAIN

1. SAJID EJAZ
DEPARTMENT OF RADIOLOGY

2. Routine- Transaxial Scan planes
For posterior and middle cranial
fossa- Anthropological baseline

3. Needed in vascular diseases
(Aneurysm) and in lesions which
obstruct the blood- brain barrier
(Tumours)
Not needed in case of Atrophia,
Trauma, Intracranial haemorrhage,
stroke, hydrocephalus and few
congenital abnormalities

4. Intracranial Haemorrhage
Tumour
Aneurysm
Trauma
Metastases
Multiple Sclerosis

5. Supine
Head on Head Support
Positioning aided by alignment lights
Orbitomeatal line parallel to transverse
alignment
Midsagittal plane perpendicular to table
and coincident with the sagittal
alignment light

6. Lateral Scan Projection Radiograph- from
5cm below to 12cm above baseline
5mm contiguous sections from foramen
magnum,the superior border of petrous
bone,to vertex
Repeated after Non Ionic contrast medium
Contrast
Voume Concentration Flowrate
50-100ml 300-370mgI/ml By Hand

8. Preferred for bony abnormalities
Transaxial or coronal planes
Transaxial- low risk of motion artefact
or dental filling, more comfortable
Coronal- Abnormalities in Petrous Bone
Slice width-(1.5 -3mm)

9. Lateral Scan Projection Radiograph- from
5cm below to 10cm above Scan reference
point
For soft tissue,3mm contiguous sections
from foramen magnum,to superior to
petrous bone
For bones- 1.5mm contiguous scans
Repeated after Non Ionic contrast medium