Download Fig. 1a Fig. 1b Fig. 2a Fig. 2b

2004-10
Fig. 1a
Fig. 1b
Fig. 2a
Fig. 2b
2004-10
Clinical history
A 56-year-old female patient presented with a clinical history of vertigo and progressive hearing loss over a 6 month period. The patient was referred to the radiology
department for suspected cerebellopontine angle pathology. The patient underwent
temporal bone CT and cranial MRI.
Findings on medical imaging
Fig 1a and b: Temporal bone CT.
There is bone destruction at the level of the left internal auditory canal (1a). The
lesion extends inferiorly to the region of the endolymphatic sac. Note the tiny bone
fragments inside the lesion (1b).
Fig 2a and b: Cranial MRI.
Axial T1-weighted sequence (2a) reveals a smoothly contoured lesion localized in the
left temporal bone adjacent to the internal auditory canal with high signal intensity.
Axial T2-weighted sequence (2b) shows high signal intensity in the tumor with a nodular component having low signal intensity. The tumor partially extends into the cerebellopontine angle.
Cimsit N.C., Akpinar I.N., Kodalli N.
Department of Radiology
Marmara University Hospital, Istanbul, Turkey
2004-10
Based on these imaging findings the diagnosis of endolymphatic sac tumor was suggested.
Comment
Endolymphatic sac tumors are recently recognized tumors of the temporal bone. They are adenocarcinomas arising from the columnar epithelium. They can present with hemorrhage when the medial
temporal bone fistulizes to the membranous labyrinth, with subacute blood in the vestibule. MR is
uniquely suited to demonstrate labyrinthine hemorrhage. Precontrast studies demonstrate high signal
intensity in the labyrinth consistent with subacute hemorrhage. Theoretically, acute hemorrhage
should be diagnosed on T2-weighted images as a very low signal intensity signal, but most patients are
examined in the subacute stage. The diagnosis is confirmed during surgery when blood is found in the
tumor sac. Definite diagnosis is made by pathological examination.
Key words
Endolymphatic sac tumor- temporal bone- vertigo
References
1. Richards PS, Clifton AG. Endolymphatic sac tumors. J Laryngol Otol 2003;117:666-669.
2. Joseph BV, Chacko G, Raghuram L, et al. Endolymphatic sac tumor: a rare cerebellopontine angle
tumor. Neurol India 2002;50:476-479.
3. Ferreira MA, Feiz-Erfan I, Zabramski JM, et al. Endolymphatic sac tumor: unique features of two
cases and review of the literature. Acta Neurochir 2002;144:1047-1053.
4. Luff DA, Simmons M, Malik T, et al. Endolymphatic sac tumors. J Laryngol Otol 2002;116:398-401.
Cimsit N.C., Akpinar I.N., Kodalli N.
Department of Radiology
Marmara University Hospital, Istanbul, Turkey