Learning objectives
To evaluated the role of diffusion-weighted images MRI in differentiating post mastoidectomy recurrent cholesteatoma from other middle ear masses.
Background
Diffusion weighted imaging is a form of MR imaging based of the variability of random Browian motion of water molecules within a voxel of tissue.
Water molecules are in constant motion,
and the rate of movement or diffusion depends on the kinetic energy,
that reflects changes at a cellular level and provides unique insight about tumor cellularity and the integrity of cell membranes.
A cholesteatoma is an abnormal,
noncanceruos skin growth composed of keratinizing squamous epithelium in the middle ear.
Cholesteatomas of the temporal bone...
Findings and procedure details
High resolution computed tomography of the temporal bone has an excellent spatial resolution,
thus even small soft-tissue lesions of the temporal bone can be accurately delineated.
However,
CT has poor specificity.
CT is required preoperative to exclude perforation of the bone. [1,2] [Fig.1]
Although MRI is unable to adequately delineate bony anatomy,
it can potentially distinguish non-specific opacification from cholesteatomas.
It can be used to detect them when the physical examination is difficult and CT findings are ambivalent.
Non-contrast MR imaging with diffusion-weighted imaging is...
Conclusion
Diffusion weighted imaging is superior for the diagnosis of cholesteatoma.
.
With these findings,
recurrent cholesteatoma can be detected with 100% specificity an 1.5T MRI machine.
It takes an increasing place in the evaluation of recurrent cholesteatoma in the follow-up of patients after canal wall-up tympanoplasty, to avoid routine second-look surgery.
References
[1] Baráth K,Huber AM,Stämpfli P,Varga Z,Kollias S Neuroradiology of cholesteatomasAJNR Am J Neuroradiol2011 32(2):221-9
[2] MigirovL,TalS, EyalA.
MRI,
not CT,
to rule out recurrent cholesteatoma and avoid unnecessary second-look mastoidectomy.Isr Med Assoc J2009:11;144–46
[3] Benjamin Henninger,Christian Kremser Diffusion weighted imaging for the detection and evaluation of cholesteatoma 2017 May 28; 9(5): 217–222.
[4] Nasr Mohamed M.
Osman,Ahmed Abdel RahmanMoustafa Talaat Abdel Hakim Ali The accuracy and sensitivity of diffusion-weighted magnetic resonance imaging with Apparent Diffusion Coefficients in diagnosis of recurrent cholesteatoma 2017; 4: 27–39.
[5]...