CT scan of neck with pre- and post- intravenous contrast, and
 with multiplanar reconstruction:

1. Abnormal fluid infiltration along bilateral neck, chiefly along
   left posterior cervical space (red arrow in figure 2), with
   adjacent bilateral subcutaneous fat stranding (yellow arrows in
   figure 1 and 2), compatible with cellulitis.
   Presence of mass effect of the lesion with vascular smooth
   narrowing along left jugular vein (green arrow in figure 1),
   suggesting vascular compression.
2. Focal fluid accumulation in midline retropharyngeal space
   (blue arrows in figure 1, 2, and 3) with indentation of
   posterior wall of airway from oropharyngeal region
   to superior mediastinum, retropharyngeal abscess can not be
   excluded.

Impression:
1. Cellulitis along bilateral neck, suspicious retropharyngeal
   abscess.