Enhanced fallopian canal as a potential marker for temporal bone vasculitis

OBJECTIVES: This study aimed to test the hypothesis that contrast‐enhanced 3D MRI with gradient‐echo sequences (CE‐3D‐GRE) can detect signs of vasculitis in the fallopian canal, which may cause otologic involvement, in four patients with antineutrophil cytoplasmic antibody‐associated vasculitis (AAV). METHODS: CE‐3D‐GRE acquired at 3.0 Tesla was performed on four patients diagnosed with granulomatosis with polyangiitis or eosinophilic granulomatosis with polyangiitis, at onset or relapse of the disease, and in remission. Clinical correlations between otologic symptoms and radiological findings were examined for each patient. Furthermore, signal intensity of the mastoid segment of the fallopian canal was compared between the ears with active disease (n = 3) and those in remission or without vasculitis (n = 3). RESULTS: Intense enhancement in the tympanic and mastoid segments of the fallopian canal was associated with development of external otitis, otitis media, and sensorineural hearing loss, and was unrelated to the presence of facial paresis. Maximal intensity projection images visualized the close relationship between the enhanced fallopian canal and middle ear inflammation. The findings were absent in remission. Signal intensity of the mastoid segment of the fallopian canal was higher in ears with active disease than in normal ears (P < .001) and decreased to normal levels during remission (P = .597). CONCLUSION: CE‐3D‐GRE can demonstrate vasculitis in the temporal bone, reflecting disease activity and the severity of otologic manifestations, including cochlear involvement, in AAV patients. Intense enhancement of the fallopian canal on CE‐3D‐GRE can be a potential marker for vasculitis of the temporal bone. LEVEL OF EVIDENCE: 5.