Brief Answer: Hi and welcome to XXXXXXX Detailed Answer: Thanks for the query. Dermoid neoplasm or cyst is a ovarian tumor which can consist of various tissues such as skin hair follicles or sweat glands. Dermoid neoplasms are are almost always benign and grow slowly. If left untreated it may be asymptomatic forever and if there significant growth then it may press surrounding organs and cause symptoms. So,depending on size,it should be surgically removed. usually if this is symptomatic or larger than 5 cm,it should be removed. Today it is done laparoscopicaly in most hospitals. If there is no indication for surgery then all you need is freqeunt follow up,every 6-12months. Folicle in other ovary,sized about 3cm is normally occuring and disappearing during your menstural cycle so this is nothing to worry about. As, I said, malignant alteration of dermoid neoplasms is rare but possible. Some features which could indicate malignancy can be seen with ultrasound but some cant so mri is necessary in some cases. usually doctos determine are there any changes in ultrasound morphology and then they recommend further tests. so this is why they recommend mri for this hyperechoic linear foci. ( it means that there is one denser part of ovary,probbaly fat). If this is fat then this isnt indicating something serious and I wouldnt even recommend mri because fat tissue is not sign of malignancy. But you can do mri to be 100% sure. Endoemtriosis is rarely mistaken for neoplasms since it is seen differently on ultarsound. Neoplasms are oval and well defined,originating from ovaries. Wish you good health. Feel free to ask. Regards

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