Large jugular bulb abnormalities involving the middle ear.

OBJECTIVE

Jugular bulb abnormalities (JBA), such as jugular bulb diverticula (JBD) or large jugular bulbs, rarely present in the middle ear. We review a large series of temporal bone histopathologic specimens to determine their prevalence and present a series of cases of JB abnormalities involving the middle ear (JBME) that shed light on the probable mechanism for their development.

PATIENTS

1,579 unique temporal bone specimens and individuals with radiographically-diagnosed JBME.

INTERVENTION

Histopathologic and clinical review of temporal bone specimens and patient presentations, radiographic findings, treatments and outcomes.

MAIN OUTCOME MEASURE

Shared characteristics of JBME.

RESULTS

There were 17 cases of JBME in 1,579 temporal bone (1.1%), of which, 15 involved the inferior mesotympanum below the level of the round window membrane (RWM), whereas 2 encroached upon the RWM or ossicles. In addition, 4 clinical cases of large JBME extending above RWM were encountered; these occurred in both sexes with ages spanning from young to old (7-66 yr). They presented with conductive hearing loss (n = 3), ear canal mass (n = 1), and intraoperative bleeding (n = 1). Radiologically, they had multiple diverticula of the JB on the side with JBME, with 1 patient demonstrating growth on serial imaging studies. All patients who underwent additional imaging had marked hypoplastic contralateral transverse sinus.

CONCLUSION

JBME abnormalities are rare, present across age groups, and may demonstrate serial growth over time. They are usually associated with multiple other diverticula within the same JB. Our clinical series suggests that JBME's development and uniquely aggressive behavior results from contralateral transverse sinus outflow obstruction.