Some Good Boston Terrier Information
With regards to the Boston Terrier and other short-nosed breeds, if fluid or debris turn out to be trapped under the elongated palate, breathing may be partial and/or the throat may be irritated. These episodes are not damaging to the dog, and may just be a bit scary to both a dog that first experiences reverse sneezing and his human owner who witnesses it for the first time.
Also, take note of this Boston Terrier information, some owners report productively calming an episode by talking to the dog in a soothing voice and rubbing the throat area gently; rubbing the throat causes the dog to swallow and this usually ends the reverse sneeze.