1. Interactive Case Tutorial

2.  Signalment: 10 year old, FS, Golden retriever  History: several weeks nasal discharge which is currently a thick, greenish/yellow discharge; currently sneezing and left ocular discharge  Study: lateral and dorsoventral views of the skull  Technique note: open mouth ventrodorsal and frontal sinus skyline views should be obtained for complete evaluation of the nasal passages

3. Focal lysis Normal teeth Increased soft tissue opacity in frontal sinus Focal lysis of vomer bone Normal right nasal passage Increased soft tissue opacity in left nasal passage Lysis of some of the ethmoid turbinates Increased soft tissue opacity in the left frontal sinus

4.  Provide a diagnosis based on your findings. Submit Destructive rhinitis involving the left nasal cavity The primary differential is nasal neoplasia (such as adenocarcinoma); this is not likely aspergillosis given the diffuse increase in soft tissue opacity of the nasal passage aspergillosis generally causes extensive cavitation and some granulomas The increased soft tissue in the left frontal sinus may be due to growth of mass or fluid build-up due to obstruction of drainage Feedback Continue

5.  Provide your recommendation for this client. Submit CT of the nasal passages to further evaluate extent and character of the disease, as well as to guide potential therapy such as radiation therapy Biopsy of the abnormal tissue Feedback Continue

6.  The entire left nasal passage and the left frontal sinus has increased soft tissue opacity  Lysis of many of the ethmoid turbinates on the left  Focal lysis of the vomer bone  The right nasal passage is relatively normal  The teeth are normal

7.  CT revealed large mass in most of the left nasal cavity  Biopsy via rhinoscopy: adenocarcinoma  Client opted for medical therapy with piroxicam Soft tissue mass filling left nasal cavity Mass in left ethmoid region, choana, and frontal sinus