الفهرس 
Aim of the workOnly 14 pages are availabe for public view
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Abstract
Summary and conclusion
Ovarian tumors, are the second most common
gynecological lesion and the fifth commonest tumor in women.
Although the final diagnosis of an ovarian tumor is based
on the histological examination, it is desirable to preoperatively
differentiate between benign, border line and invasive ovarian
cancers و in order to decide if surgery is required, and which type
of operation is appropriate. Thus, it can help avoiding unnecessary
procedure especially in postmenopausal women and help deciding
for conservative surgery for younger ones wishing to preserve
fertility.
Trans vaginal ultrasound (TVUS) is the first imaging
modality that can be used for detection of adnexal mass lesion.
However, lesion characterization is done with the help of MRI.
Conventional MRI provides soft tissue characterization based on
different signal intensities and contrast uptake on post contrast
images.
Being a cost effective choice, and in addition to its ability
for accurate diagnosis, it can replace computed tomography (CT)
in preoperative assessment
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79
With the development of recent technologies, new
functional MRI sequences are being used. Of these, are the
diffusion weighted images (DWI) and Magnetic resonance
spectroscopy(MRS). DWI is used in the abdomen and pelvis after
it has been established as a useful functional imaging tool in
neurologic applications for a number of years.
Functional imaging is becoming increasingly important in
the evaluation of cancer patients because of the limitations of
morphologic imaging.
DW-MRI has been incorporated into conventional
abdominopelvic imaging protocols in oncology with short
imaging times (<5 min), good signal to noise ratio and robust
performance against sources of artifact . This technique is used for
lesion characterization, staging, and monitoring therapeutic
response, and Differentiation of malignant from benign lesions on
ADC criteria , However, since there are some overlaps on DWI
between benign and malignant gynecological disease, DWI
evaluation of the lesions should be done in concert with
conventional imaging, to distinguish between benign and
malignant lesions. The advantages of DWI include its costeffectiveness
and brevity of execution, its complete
noninvasiveness, its lack of ionizing radiation, and the fact that it
does not require injection of contrast material, thus enabling its
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80
use in patients with reduced renal function. DWI could provide
supplemental information in patients with gynecological disorders
and could easily be incorporated into standard clinical protocols
utilizing MRI.
Proton magnetic resonance spectroscopy (MRS) employs
the same hardware as MRI in order to noninvasively explore the
biochemical composition of tissue through the identification and
quantification of important chemicals in various body tissues and
thereby characterize normal and diseased tissue types
Proton MRS is used to measure the concentrations of
compounds containing lactate, choline (Cho), creatine (Cr), Nacetylaspartate
(NAA) and lipids in ovarian tumors and it can help
in tissue characterization as in the examples:
higher lactate peaks in malignant lesions compared with
benign tumors.
the incidence of a lipid peak was significantly higher in
malignant tumors than in benign epithelial tumors.
The combination of DWI and Magnetic resonance spectroscopy to
conventional MRI implies:
Using a completely noninvasive techniques with no
radiation exposure
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81
It improves the specificity of MRI and thus increasing the
radiologist‘s confidence in image interpretation which will finally
reflects on the patients‘ outcome and prognosis