Endovaginal Magnetic Resonance Imaging Research Articles

Loop-Mediated Isothermal Amplification Assay for Detecting Tumor Markers and Human Papillomavirus: Accuracy and Supplemental Diagnostic Value to Endovaginal MRI in Cervical Cancer.

ObjectiveTo establish the sensitivity and specificity of a human papillomavirus (HPV) and tumor marker DNA/mRNA assay for detecting cervical cancer that is transferrable to a Lab-on-a-chip platform and determine its diagnostic benefit in early stage disease when used in conjunction with high-resolution endovaginal magnetic resonance imaging (MRI).MethodsForty-one patients (27 with Stage1 cervical cancer [Group1] and 14 non-cancer HPV negative controls [Group2]) had DNA and RNA extracted from cervical cytology swab samples. HPV16, HPV18, hTERT, TERC/GAPDH and MYC/GAPDH concentration was established using a loop mediated isothermal amplification (LAMP) assay. Thresholds for tumor marker detection for Group1 were set from Group2 analysis (any hTERT, TERC/GAPDH 3.12, MYC/GAPDH 0.155). Group 1 participants underwent endovaginal MRI. Sensitivity and specificity for cancer detection by LAMP and MRI individually and combined was documented by comparison to pathology.ResultsSensitivity and specificity for cancer detection was 68.8% and 77.8% if any tumor marker was positive regardless of HPV status (scenario1), and 93.8% and 55.8% if tumor marker or HPV were positive (scenario 2). Adding endovaginal MRI improved specificity to 88.9% in scenario 1 (sensitivity 68.8%) and to 77.8%% in scenario2 (sensitivity 93.8%).ConclusionSpecificity for cervical cancer detection using a LAMP assay is superior with tumor markers; low sensitivity is improved by HPV detection. Accuracy for early stage cervical cancer detection is optimal using a spatially multiplexed tumor marker/HPV LAMP assay together with endovaginal MRI.

MRI in stress urinary incontinence: endovaginal MRI with an intracavitary coil and dynamic pelvic MRI.

To evaluate both morphology of the urethra and its supporting structures using endovaginal magnetic resonance imaging (EV-MRI) and the grade of the bladder neck prolapsus using dynamic pelvic MRI (DP-MRI) in women with stress urinary incontinence (SUI). We compared 25 women with SUI and 8 controls according to the different layers of the urethra, the degree of distortion in the periurethral, paraurethral, and pubourethral ligaments, the vesicourethral angle, the retropubic space, and the thickness of the puborectal muscle. The SUI group was also evaluated according to the number of deliveries and degree of the bladder neck prolapsus. Significant differences were found in the thickness of each three layers of the urethra between the two groups (P < .05). There was a significantly higher pubourethral ligament distortion (P = .024) and larger vesicourethral angle (P = .000) in women with SUI. In women with SUI, there was no significant relationship between the number of deliveries and the degree of the bladder neck prolapsus (P > .05). The combined usage of the EV-MRI and DP-MRI can provide complementary information concerning certain structural abnormalities with specific dysfunction, such as vesicourethral angle increase and pubourethral ligament distortion in patients with SUI.

Endovaginal magnetic resonance imaging of stage 1A/1B cervical cancer with A T2- and diffusion-weighted magnetic resonance technique: Effect of lesion size and previous cone biopsy on tumor detectability

Objective. To evaluate the effects of previous cone biopsy and lesion size on detectability of stage 1a/1b cervical cancer using endovaginal T2- and diffusion-weighted magnetic resonance imaging. Methods. One hundred and thirteen patients with cervical tumor were imaged using an endovaginal coil with T2-weighted (T2-W) and diffusion-weighted single-shot echo-planar sequences; 85 managed surgically (58 with prior cone biopsy/LLETZ) were evaluated. T2-W images and ADC maps viewed simultaneously were scored positive or negative for tumor and compared with histology at surgery. MRI tumor volumes, maximum radiological and histological dimensions were recorded. ROC analysis determined the MRI volume with optimal sensitivity/specificity for identifying tumor in those without and with prior cone biopsy/LLETZ and the maximum histological dimension for correctly identifying tumor with MRI. Mean apparent diffusion coefficients (ADCs) from tumor and adjacent normal epithelium were compared. Results. Sensitivity and specificity for detecting tumor in those without (100%; 100% respectively) and with (80%; 78.9% respectively) prior cone biopsy/LLETZ were significantly different ( p < 0.001). Following cone biopsy/LLETZ, MRI tumor volume of 83 mm 3 detected tumor with 80% sensitivity, 94.7% specificity; a 5.3 mm maximal histological dimension was detected on MRI with 100% sensitivity, 100% specificity. Tumor ADCs were significantly lower ( p < 0.001) than paired normal epithelial tissue (median, 988 × 10 −6 mm 2/s vs. 1564 × 10 −6 mm 2/s) but neither tumor nor epithelial ADCs differed significantly between patients with or without prior cone biopsy/LLETZ ( p = 0.48 and 0.15, respectively). Conclusions. Endovaginal MRI with T2- and diffusion-weighted sequences has significantly lower sensitivity and specificity for tumor detection following cone biopsy/LLETZ.

Cervical cancer: Value of an endovaginal coil magnetic resonance imaging technique in detecting small volume disease and assessing parametrial extension

Background. Estimation of tumor volume by endovaginal magnetic resonance (MR) imaging is a better indicator of prognosis than FIGO stage in women with cervical cancer treated by standard modalities. However, the introduction of fertility conserving surgical techniques makes fresh demands upon imaging of these small tumors. Objective. To determine the sensitivity and specificity of endovaginal MRI in detecting small volume disease and assessing parametrial extension in uterine cervical cancer by comparing the findings with those at radical hysterectomy in order to establish its role in guiding the surgical decision-making process preoperatively. Methods. A retrospective study was performed in 119 patients who underwent endovaginal and external phased array MR imaging at 0.5 T or 1.5 T before radical hysterectomy. Tumor presence within the cervix and parametrial extension was noted on the endovaginal images. Histopathological findings were correlated with MR imaging results for all patients. Results. The sensitivity and specificity for detecting tumor by endovaginal MR imaging in the 119 patients were 96.9 and 59.0%, respectively. Thirty-six percent of tumors were ≤1 cm 3 in volume. For these, sensitivity and specificity for tumor detection were 87% and 65% respectively. For evaluation of parametrial status, sensitivity was 80%, and specificity was 91.3%. A cut-off MRI tumor volume of 5.2 cm 3 predicted histologically confirmed lymph node metastases with a sensitivity of 78.6% and specificity of 72.5%. Conclusion. Endovaginal magnetic resonance imaging has high sensitivity in the preoperative staging of uterine cervical cancer even for tumors ≤1 cm 3. It is an invaluable technique in planning fertility-conserving or radical surgical treatment of early stage cervical cancer.

Endovaginal Magnetic Resonance Imaging of the Female Urethra

Magnetic resonance imaging (MRI) is playing an important role in the clinical evaluation of women presenting with urethral symptoms. Voiding cystourethrography, direct urethrography, and pelvic sonography provide limited information on abnormalities that are in continuity with the urethra. On the other hand, urethra and periurethral tissues can be noninvasively evaluated by high-resolution endocavitary MRI. Because of its multiplanar capability and high tissue contrast, endovaginal MRI is an extremely reliable diagnostic test in the evaluation of urethral abnormalities. In this article, the utility of endovaginal MRI in the detection and characterization of a wide spectrum of urethral pathologic conditions, such as congenital anomalies, diverticula, urethritis, and benign and malignant neoplasms, is discussed.

Magnetic resonance imaging of the primary site in stage I cervical carcinoma: A comparison of endovaginal coil with external phased array coil techniques at 0.5T

Objective: To compare endovaginal with pelvic phased array coil magnetic resonance imaging (MRI) in detection of Stage I cervical carcinoma by correlating the findings with histopathology. Patients and Methods: Forty consecutive patients with Stage I cervical carcinoma confirmed histologically were studied using an endovaginal coil alone immediately followed by a pelvic phased array coil. T1-W transverse and T2-W FSE sagittal images made with each coil were analyzed independently by two radiologists noting the presence and size of a mass within the cervix and any parametrial extension or involvement of adjacent organs. Tumor volumes were measured using the electronic calliper to compute tumor area on each slice and multiplying by the slice thickness. Thirty patients underwent radical hysterectomy, one a trachylectomy, one simple hysterectomy and four extended cone biopsies. Four patients had radiotherapy to the primary tumor. Following surgery, histopathologic findings were recorded and tumor volumes measured. Results: Tumor volumes ranged from 0–106 cm3(median 1.4 cm3, mean 9 ± 19.4 cm3). Thirty-six patients had correlation of the primary site with the surgical specimen. Agreement between observers was excellent for both endovaginal (k = 0.90) and pelvic phased array (k = 0.96) techniques. Combined sensitivity and specificity for both observers of endovaginal MR imaging for detection of tumor was 96% and 70%, respectively; for pelvic phased array imaging sensitivity was substantially less at 54%. Specificity was higher at 83.7%, probably because small abnormalities were seldom visible. In patients treated surgically, early parametrial involvement in four women on endovaginal MRI was confirmed histologically in two. Pelvic phased array imaging showed early parametrial involvement in four women and was confirmed in one. Conclusion: Endovaginal MRI adds substantially to information from pelvic phased array images in the preoperative assessment of patients with early cervical cancer. J. Magn. Reson. Imaging 2000;12:1020–1026. © 2000 Wiley-Liss, Inc.

Female pelvic floor: endovaginal MR imaging of normal anatomy.

To demonstrate the anatomy of the female pelvic floor with endovaginal magnetic resonance (MR) imaging. Ten healthy nulliparous volunteers (age, 22-26 years) underwent MR imaging with an endovaginal coil. Findings on endovaginal MR images in the volunteers were correlated with findings on endovaginal MR images and cross-sectional anatomic slices obtained in three cadavers. The endovaginal coil was well tolerated by all volunteers. Pelvic floor structures such as the pelvic diaphragm and the urogenital diaphragm were well depicted. Previously undescribed urethral supporting structures--the periurethral and paraurethral ligaments--were visualized. The zonal anatomy of the urethra was clearly visible. The endovaginal MR imaging findings in the volunteers correlated with the endovaginal MR findings and gross anatomy in the cadavers. Endovaginal MR imaging clearly demonstrates the anatomy of the female pelvic floor and urethra.