Role of new magnetic resonance imaging modalities in diagnosis of orbital masses: a clinicopathologic correlation.
OBJECTIVE
To evaluate the role of diffusion-weighted magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy (MRS) in the diagnosis of different orbital masses and their advantages over conventional MRI.


METHODS
The study included 20 patients presenting with proptosis. Every patient was subjected to thorough clinical examination, conventional MRI "T1 weighted, T2 weighted, and postcontrast T1 weighted if needed," diffusion-weighted MRI, and proton MRS. Orbitotomy was performed, the orbital mass was excised, and histopathological examination was performed.


RESULTS
Diffusion-weighted MRI could differentiate between benign lesions and malignant tumors in 70% of cases; however, overlap occurred in 30% of cases with benign tumors showing restricted diffusion whereas proton MRS could differentiate between benign and malignant tumors in 90% of cases.


CONCLUSIONS
Diffusion-weighted MRI and proton MRS can potentially increase the accuracy of diagnosis of orbital masses through in vivo tissue characterization. Magnetic resonance spectroscopy seems to be the more accurate modality.
Roshdy
Nader
N
Mansoura Ophthamic Center, Mansoura University, Mansoura, Egypt.
Shahin
Maha
M
Kishk
Hanem
H
El-Khouly
Sherif
S
Mousa
Amany
A
Elsalekh
Iman
I