The role of magnetic resonance imaging in the postoperative management of cholesteatomas.
Conventional CT and MRI scans have low specificity when it comes to differentiating granulation tissue from relapsing cholesteatoma.


OBJECTIVE
this paper aims to analyze the use of DWI and delayed post-contrast T1-weighed imaging in the detection of recurring cholesteatomas.


METHODS
this is a cross-sectional prospective study that looked at 17 cholesteatoma patients postoperatively. All patients underwent diffusion magnetic resonance imaging at 1.5T, T1, T2, and delayed post-contrast T1 and images were produced from both coronal and axial planes. Two radiologists assessed the images and decided consensually that the presence of hyperintensive signal in DWI on T2, iso/hypointensive signal on T1, and absence of contrast uptake were indicative of relapsing cholesteatoma. Surgical review findings were compared to DWI scans.


RESULTS
eleven of the twelve cases of recurring cholesteatoma presented hyperintensive signal in the DWI scans. None of the patients with granulation tissue in the surgical wound presented hyperintensive signal in the DWI scans. A patient with an abscess in the internal acoustic meatus also presented a hyperintensive signal in the DWI scans. Sensibility, specificity, positive predictive value and negative predictive value were 91.6%, 60.0%, 84.6%, and 75.0%, respectively.


CONCLUSIONS
DWI combined with delayed post-contrast T1 SE sequence proved to be useful in the differential diagnosis of granulation tissue and recurring cholesteatoma.
Toyama
Carlos
C
Specialist, MD, researcher.
da Costa Leite
Claudia
C
Associate Professor at FMUSP, Head of the Magnetic Resonance Sector at Fundação Faculdade de Medicina.
Filho
Iulo Sérgio Baraúna
ISB
Specialist, Fellowship in ear surgery.
de Brito Neto
Rubens Vuono
RV
Post-PhD, Assistant Professor at USP.
Bento
Ricardo Fereira
RF
Full Professor at the Department of Ophthalmology and Otorhinolaryngology at FMUSP.
Cerri
Giovanni Guido
GG
Full Professor at the Department of Radiology at FMUSP.
Gebrim
Eloisa Maria Melo Santiago
EMMS
PhD, Head of the Computerized Tomography Department at the Radiology Institute at FMUSP. University Hoispital of the Faculdade de Medicina da Universidade de São Paulo.
D018424:Cholesteatoma, Middle Ear / Q000473:pathology* / Q000517:prevention & control* / Q000601:surgery; D003287:Contrast Media; D003430:Cross-Sectional Studies; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D008297:Male; D008416:Mastoid / Q000473:pathology / Q000601:surgery*; D008875:Middle Aged; D011183:Postoperative Complications / Q000175:diagnosis*; D011184:Postoperative Period; D011446:Prospective Studies; D012008:Recurrence; D014057:Tomography, X-Ray Computed
D003287:Contrast Media