الفهرس 
Introduction & aim of workOnly 14 pages are availabe for public view
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Abstract
Cervical cancer is the second most common gynecologic malignancy worldwide and is typically seen in younger women. Cervical cancers start in the lining epithelium of the cervix. The majority of cervical cancers are from squamous cells. The development of cervical cancer is very slow. It starts as a pre- cancerous condition called dysplasia. It usually takes years for pre-cancerous changes to turn into cervical cancer. This pre- cancerous changes when detected is 100% treatable. Patients with cervical cancer do not usually have problems until the cancer is advanced and has spread. Pap smears are used for screening pre- cancers and cancer, but do not offer the final diagnosis. If abnormal changes are found, the cervix is usually examined under
magnification (colposcopy) and conically biopsied.
Once cervical cancer is diagnosed its stage must be determined. Accurate cervical cancer staging is crucial for appropriate treatment selection and treatment planning. Armed with information about the extent and volume of cervical lesion, the clinician can plan fertility conserving or radical surgery, chemo or radiotherapy with greater confidence.
Staging is based on clinical FIGO criteria that include findings from physical examination, colposcopy, lesion biopsy, radiologic studies (e.g. chest radiography, intravenous urography, and barium enema), and endoscopic studies (e.g. cystoscopy, sigmoidoscopy). Compared with surgical staging, FIGO clinical staging has been shown to be in accurate. The greatest difficulties
in the clinical staging are the estimation of tumor size, especially if the tumor is primarily endocervical in location, the assessment of parametrial and pelvic sidewall invasion and the evaluation of lymph node and distant metastases. Modern cross-sectional imaging, which can assist in the evaluation of these prognostic factors, has become an important adjunct to the clinical assessment of cervical cancer. Many articles in the literature showed the superiority of CT and MRI to clinical staging.
MRI has excellent soft-tissue contrast resolution, which exceeds that of CT and US. Consequently, MRI is significantly more valuable in the assessment of the size of the tumor, the depth of cervical invasion, and the local-regional extent of the disease. CT and MRI are approximately equivalent, and both are significantly superior to US, in the detection of enlarged lymph nodes, Thus CT and MRI are more accurate staging modalities but they are not warranted in patients with small-volume early disease (<2 cm³) because of the low probability of parametrial invasion and nodal metastasis.
The precision of MRI can be improved substantially by using a localized receiver coil close to the area of interest. A ring endovaginal receiver coil is designed to obtain high resolution images of the cervix with detailed delineation of the zonal anatomy. The spatial resolution of the endovaginal technique ensures that very small tumors and even early spread to the parametrium can be detected. The smallest tumor noted on endovaginal MRI is approximately 0.1 cm³. Such small lesions
are not visible by the pelvic phased array coil. Smaller lesions continue to represent a diagnostic challenge.
Endovaginal MRI requires both T1W and T2W images in two planes. The sagittal plane is most useful for imaging the tumor, assessing the distance from the edge of the cervix and assessing vaginal involvement. The transverse plane is critical for assessing parametrial involvement. Invasive tumors are mostly demonstrated as a centrally expanding, intermediate signal intensity mass in T2W images and parametrial invasion is usually recognized with ease as a break in the continuity of low signal outer cervical stromal ring and by seeing the intermediate signal of the tumor extending and blending with the high signal parametrial fat.
Tissue characterization of cervical lesions by ¹H-MRS used in conjunction with endovaginal MR imaging proved to be a promising modality in detection of cervical cancer. The presence of positive triglyceride-CH₂ resonance can be used to detect and
confirm the presence of malignancy.
Phosphorous-31 MRS (³¹P MRS) has significant potential in assessing the radiation response of human tumours because phosphorous metabolism of energy and membrane phospholipids can be measured in vivo.
The high-spatial-resolution images obtained with an endovaginal coil together with DW MR imaging may allow more accurate identification of small tumors and improve treatment
planning, particularly when considering fertility sparing procedures in patients with stage Ia and Ib1 invasive cervical carcinoma
In Conclusion:
• High-resolution MRI of the cervix using an endovaginal coil provides accurate assessment of the intra and extra cervical extents of early stage cervical neoplasia and correctly identifies lesions ≤ 2 cm³ with high sensitivity. As a complementary study pelvic phased MRI is performed in every case for pretheraputic evaluation of the pelvic organs, pelvic sidewall and for lymph node staging.
• In patients without prior cone/LLETZ biopsy, endovaginal
T2 weighted images detected cervical tumors <0.9cm3 with
100% sensitivity, 100% specificity.
• H-MRS used in conjunction with endovaginal MR imaging for early detection of cervical cancer& Phosphorous-31
MRS used in detection of tumour response to radtiotherapy.
• The high-spatial-resolution images obtained with an endovaginal coil together with DW MR give an ultrafast sequence without oral or IV contrast material used in early detection & staging of cervical cancer.
• High-resolution MRI of the cervix using an endovaginal coil has important role in Selection of best treatment modality for each patient
• High-resolution MRI of the cervix using an endovaginal coil used for Detection of local tumor recurrence ,it enables differentiation of postoperative or radiation-induced scars from recurrent tumor.