الفهرس | Only 14 pages are availabe for public view |
Abstract Ovarian tumors are considered the most common cause of death among all other tumors of the female genital system. Most ovarian tumors manifest as cystic masses and differential diagnosis on the basis of imaging finding is difficult. Currently used techniques such as ultrasound with color Doppler, computed tomography, and magnetic resonance imaging play an important role in the detection, characterization, staging, treatment planning and follow-up of ovarian tumors. However, there are some cases in which the differentiation between benign and malignant ovarian tumors is difficult. Proton magnetic resonance spectroscopy (H1- MRS) may help solve this clinical problem by analyzing the composition of fluid from ovarian cyst, providing details of tumors metabolism that might assist tumor grading and leading to a better understanding of the biochemical pathways found within the lesion. There are two MRS techniques: Single-voxel & multiple-voxel techniques and both have its own advantages & disadvantages. In general, magnetic resonance spectroscopy (H1- MRS) was able to detect higher signal peaks of different metabolites in malignant ovarian tumors than in benign ovarian tumors. However, there are certain considerations taken in which high lactate signal was detected in the fluid component of dermoid cysts (as lactate signal is detected in the cystic portion of ovarian tumors), choline peak was found in benign tumors as in thecoma (as choline peak is detected in all cases of solid tumors or solid parts of ovarian tumors) and a high lipid peak was detected in dermoid cysts and in benign teratomas (as high lipid peak is due to mainly a tumor’s fatty component and the presence of the methylene group in fatty acid chains). Since the metabolic composition of the tumor cells is a reflection of the tumor nature, MRS analysis of ovarian tumors may help in their preoperative differential diagnosis. The combined use of MRI or CT prior to MRS provides valuable information about the nature and composition of the tumor. In conclusion, magnetic resonance spectroscopy (MRS) is a non invasive chemical analysis that plays an important role in the detection of ovarian tumors by differentiating between them whether being benign or malignant. |