What does sinusitis look like in a baby?

Depends: Before 4-6 m babies essentially have no sinus cavities. By a year, the maxillary & ethmoid sinuses are partially developed and inflammation can be seen as creamy nasal debris that often descends down the back of the throat like a waterfall during oral exam. Xrays < 1yr are rarely helpful as the sinus cavities are often filled by normal mucous at that age rather than trapped pus seen when older.