Presentation
Facial plastic surgery planning
Patient Data
This study is a normal CT of the face without intravenous contrast.
The acquisition parameters are as follows:
- Patient position: head first supine
- Scan range: 1 cm above frontal sinus to 1 cm below chin
- Scan field of view: head
- Scan mode: axial
- Rotation time: 1 second
- Pitch: not applicable
- Collimation: 0.625 mm
- kV: 120 kVp
- mA: 40 mA
The axial images are displayed with a field of view 184 mm diameter on a 512 x 512 matrix.
The axial bone window images are reconstructed at 0.625 mm slice thickness, 0.625 spacing, using a bone kernel with 30% adaptive statistical iterative reconstruction V (ASIR V), displayed here with a window centered at 900 HU, width 3000 HU. Coronal and sagittal reformats were created at 1 mm slice thickness.
The axial soft tissue window images are reconstructed at 2.5 mm slice thickness, 2.5 mm spacing, using a standard kernel with 30% ASIR, displayed here with a window centered at 40 HU, width 450 HU.
Note that some of the inferior images (below the chin) on the axial bone series are omitted due to upload size restrictions. See the coronal/sagittal series for the full scan range.
3D volume render technique (VRT) was employed with diffuse lighting, with 2 degree increment rotation (around the vertical axis) or tumbling (around the horizontal axis).
Case Discussion
Optimal evaluation of bony detail on craniofacial CT is obtained by using a bone reconstruction kernel (emphasizing edges), tight display field of view (to maximize use of the matrix), thin slices (ideally 1 mm or less), and, depending on the indications, multiplanar 2D reconstruction and 3D volume rendering. The display window should be adjusted for dense bone and teeth as appropriate.
Unable to process the form. Check for errors and try again.