Paula J. Woodward

Early Invasive Cervical Cancer: Tumor Delineation by Magnetic Resonance Imaging, Computed Tomography, and Clinical Examination, Verified by Pathologic Results, in the ACRIN 6651/GOG 183 Intergroup Study

PURPOSE To compare magnetic resonance imaging (MRI), computed tomography (CT), and clinical examination for delineating early cervical cancer and for measuring tumor size. PATIENTS AND METHODS A 25-center study enrolled 208 patients with biopsy-proven invasive cervical cancer for MRI and CT before attempted curative radical hysterectomy. Each imaging study was interpreted prospectively by one onsite radiologist and retrospectively by four independent offsite radiologists, who were all blinded to surgical, histopathologic, and other imaging findings. Likelihood of cervical stromal and uterine body involvement was rated on a 5-point scale. Tumor size measurements were attempted in three axes. Surgical pathology was the standard of reference. RESULTS Neither MRI nor CT was accurate for evaluating cervical stroma. For uterine body involvement, the area under the receiver operating characteristic curve was higher for MRI than for CT for both prospective (0.80 v 0.66, respectively; P = .01) and retrospective (0.68 v 0.57, respectively; P = .02) readings. Retrospective readers could measure diameter by CT in 35% to 73% of patients and by MRI in 79% to 94% of patients. Prospective readers had the highest Spearman correlation coefficient with pathologic measurement for MRI (r(s) = 0.54), followed by CT (r(s) = 0.45) and clinical examination (r(s) = 0.37; P < .0001 for all). Spearman correlation of multiobserver diameter measurements for MRI (r(s) = 0.58; P < .0001) was double that for CT (r(s) = 0.27; P = .03). CONCLUSION In patients with cervical cancer, MRI is superior to CT and clinical examination for evaluating uterine body involvement and measuring tumor size, but no method was accurate for evaluating cervical stroma.

MRI of the female pelvis

MRI is a proven modality to evaluate the female pelvis. Excellent soft tissue contrast, sensitivity for the detection of fluid, and the multiplanar imaging capabilities of MR allow noninvasive demonstration of normal anatomy and pathological processes. Most female pelvic MRI studies are performed to answer specific questions and must, therefore, follow carefully developed protocols, which are discussed in this article. The principal MRI techniques and strategies outlined in this work include: (1) the evaluation of reproductive dysfunction, anatomic variants; (2) specific obstetrical applications; (3) oncologic evaluation and tumor staging; (4) problem solving (i.e., the characterization of abnormalities detected by ultrasound); and (5) the evaluation of urethral disease.

Accuracy of ultrasound for the prediction of placenta accreta

OBJECTIVE Ultrasound has been reported to be greater than 90% sensitive for the diagnosis of accreta. Prior studies may be subject to bias because of single expert observers, suspicion for accreta, and knowledge of risk factors. We aimed to assess the accuracy of ultrasound for the prediction of accreta. STUDY DESIGN Patients with accreta at a single academic center were matched to patients with placenta previa, but no accreta, by year of delivery. Ultrasound studies with views of the placenta were collected, deidentified, blinded to clinical history, and placed in random sequence. Six investigators prospectively interpreted each study for the presence of accreta and findings reported to be associated with its diagnosis. Sensitivity, specificity, positive predictive, negative predictive value, and accuracy were calculated. Characteristics of accurate findings were compared using univariate and multivariate analyses. RESULTS Six investigators examined 229 ultrasound studies from 55 patients with accreta and 56 controls for 1374 independent observations. 1205/1374 (87.7% overall, 90% controls, 84.9% cases) studies were given a diagnosis. There were 371 (27.0%) true positives; 81 (5.9%) false positives; 533 (38.8%) true negatives, 220 (16.0%) false negatives, and 169 (12.3%) with uncertain diagnosis. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 53.5%, 88.0%, 82.1%, 64.8%, and 64.8%, respectively. In multivariate analysis, true positives were more likely to have placental lacunae (odds ratio [OR], 1.5; 95% confidence interval [CI], 1.4-1.6), loss of retroplacental clear space (OR, 2.4; 95% CI, 1.1-4.9), or abnormalities on color Doppler (OR, 2.1; 95% CI, 1.8-2.4). CONCLUSION Ultrasound for the prediction of placenta accreta may not be as sensitive as previously described.

The Cavum Septi Pellucidi Why Is It Important

Objective. The cavum septi pellucidi (CSP) is routinely imaged in the fetal brain during obstetric sonography; in fact, for well over a decade, assessment of the CSP has been considered part of the required elements of a standard examination of fetal morphology in guidelines developed by multiple specialty societies. Our objective is to present the 4 reasons why all practicing sonologists and sonographers should be familiar with this anatomic structure. Methods. Prenatal sonograms and magnetic resonance imaging examinations are used to review the following topics: terminology, embryology, and anatomy of the CSP; pitfalls in its identification; and a wide variety of abnormalities (predominantly relating to nonvisualization) associated with the CSP. Results. Embryologic development of the CSP is intimately associated with the corpus callosum (CC); thus, correct identification of the CSP essentially excludes complete agenesis of the CC. Absence of the CSP is associated with an extremely wide spectrum of neuroanatomic malformations: these range from the lethal entities of hydranencephaly and alobar holoprosencephaly; to the potentially serious but nonlethal entities of schizencephaly, porencephaly, basilar encephaloceles, severe hydrocephalus, and the less severe prosencephalic cleavage disorders (including syntelencephaly); to the normal variant, the rare and somewhat controversial entity of isolated septal deficiency. The value of noting that the absent CSP allows diagnosis of very subtle and easily overlooked abnormalities such as septo‐optic dysplasia is presented. Conclusions. Correct recognition of the CSP provides welcome reassurance of proper development of the central forebrain.

Early invasive cervical cancer: MRI and CT predictors of lymphatic metastases in the ACRIN 6651/GOG 183 intergroup study

PURPOSE To compare MRI, CT, clinical exam and histopathological analysis for predicting lymph node involvement in women with cervical carcinoma, verified by lymphadenectomy. METHODS A 25-center ACRIN/GOG study enrolled 208 patients with biopsy-proven invasive cervical cancer for MRI and CT prior to attempted curative radical hysterectomy. Each imaging study was interpreted prospectively by one onsite radiologist, and retrospectively by 4 independent offsite radiologists, all blinded to surgical, histopathological and other imaging findings. Likelihood of parametrial and uterine body involvement was rated on a 5-point scale. Tumor size measurements were attempted in 3 axes. Association with histologic lymph node involvement, scored as absent, pelvic only and common iliac or paraaortic, was evaluated using Cochran-Mantel Haenszel statistics, univariate and multivariate logistic regression, generalized estimating equations, accuracy statistics and ROC analysis. RESULTS Lymphatic metastases were found in 34% of women; 13% had common iliac nodal metastases, and 9% had paraortic nodal metastases. Based on the retrospective multi-observer re-reads, the average AUC for predicting histologic lymph node involvement based on tumor size was higher for MRI versus CT, although formal statistic comparisons could not be conducted. Multivariate analysis showed improved model fit incorporating predictors from MRI, but not from CT, over and above the initial clinical and biopsy predictors, although the increase in discriminatory ability was not statistically significant. CONCLUSION MRI findings may help predict the presence of histologic lymph node involvement in women with early invasive cervical carcinoma, thus providing important prognostic information.

Magnetic resonance imaging of the female pelvis

Evaluation of pelvic pathology is an important part of most radiology practices. Magnetic resonance imaging (MRI) has proven itself to be a useful and cost-effective method in evaluating many of these diseases. This article reviews appropriate MR imaging techniques and findings of common gynecologic disorders. Uterine pathology is categorized into congenital anomalies, benign lesions (leiomyomas, adenomyosis, endometrial polyps, and nabothian cysts), and malignancies (endometrial and cervical carcinoma). Adnexal pathology reviewed includes endometriosis, polycystic ovaries, teratomas, and benign and malignant ovarian epithelial tumors.

Assessing the role of magnetic resonance imaging in the management of gravid patients at risk for placenta accreta.

RATIONALE AND OBJECTIVES The role of magnetic resonance imaging (MRI) in the diagnosis of placenta accreta remains uncertain. The purpose of this study was to evaluate the incremental benefit of MRI after ultrasound (US) for a large cohort of gravid patients at risk for a placenta accreta. MATERIALS AND METHODS A retrospective review of outcomes in women with risk factors for a placenta accreta between November 1995 and February 2008 was performed. Inclusion criteria were high-risk women with abnormal placenta implantation on US or operative diagnosis of placenta accreta, with or without a prenatal MRI. Delivery mode, diagnosis, and transfusion requirements were compared. RESULTS Ranging in age from 19 to 43 years, with zero to five prior cesarean sections, 139 women met inclusion criteria. The MRI was performed in 28.7% (40/139). US, MRI, and operative diagnoses were highly correlated (P < .001). Women who underwent both US and MRI were more likely to deliver by cesarean hysterectomy (P < .001). When the cohort is stratified by outcome diagnosis (normal, previa, accreta), no difference in delivery mode is found; regardless of whether subjects were imaged by US alone or US and MRI. Transfusion requirements were highest in the US and MRI group (mean of 3.9 units vs. 0.9 units in the US only group, P < .001). CONCLUSION This study fails to demonstrate that the incremental use of MRI for placenta accreta changes delivery mode in stratified analysis. Patients who underwent both US and MRI were most likely to have a cesarean hysterectomy delivery, and required more blood products, suggesting that undergoing tests may be indicative of an abnormal and at risk patient population.

A multisite phase iii study of the safety and efficacy of a new manganese chloride-based gastrointestinal contrast agent for mri of the abdomen and pelvis

The purpose of this study was to evaluate the safety and efficacy of a manganese chloride‐based oral magnetic resonance (MR) contrast agent during a Phase III multisite clinical trial. Two hundred seventeen patients were enrolled who were already scheduled for MRI of the abdomen and/or pelvis. In this group of patients, it was postulated that the use of an oral agent would better allow discrimination of pathology from bowel. Patients with known gastrointestinal pathology including peptic ulcer disease, inflammatory bowel disease, obstruction, or perforation were excluded to minimize confounding variables that could affect the safety assessment. Of these 217 patients, 18 received up to 900 mL of placebo, and 199 patients were given up to 900 mL of a manganese chloride‐based oral contrast agent, LumenHance® (Bracco Diagnostics, Inc.). Safety was determined by comparing pre‐ and post‐dose physical examinations, vital signs, and laboratory examinations and by documenting adverse events. Efficacy was assessed by unblinded site investigators and two blinded reviewers who compared pre‐ and post‐dose T1‐ and T2‐weighted MRI scans of the abdomen and/or pelvis. In 111 (57%) of the 195 cases evaluated for efficacy by site investigators (unblinded readers), MRI after LumenHance provided additional diagnostic information. Increased information was found by two blinded readers in 52% and 51% of patients, respectively. In 44/195 cases (23%) unblinded readers felt the additional information would have changed patient diagnosis and in 50 patients (26%), it would have changed management and/or therapy. Potential changes in patient diagnosis or management/therapy were seen by the two blinded readers in 8–20% of patients. No clinically significant post‐dose laboratory changes were seen. Forty‐eight patients (24%) receiving LumenHance and four patients (22%) receiving placebo experienced one or more adverse events. Gastrointestinal tract side effects were most common, seen in 29 (15%) of LumenHance patients and in 3 (17%) of the placebo patients. LumenHance is a safe and efficacious oral gastrointestinal contrast agent for MRI of the abdomen and pelvis.J. Magn. Reson. Imaging 1999;10:15–24.

Magnetic resonance evaluation of congenital uterine anomalies

Congenital malformations of the uterus (also known as müllerian duct anomalies) exist as a spectrum of disorders; each of these, to some extent, is associated with reproductive dysfunction. Significant improvements in imaging methods such as ultrasound and magnetic resonance have the potential to eliminate the need for invasive evaluation of patients with suspected uterine anomalies. This article reviews the relevant embryology and classification of müllerian duct anomalies as well as the relationship between the imaging features and general therapeutic options.

Cloacal Malformation Embryology, Anatomy, and Prenatal Imaging Features

Cloacal malformation is a rare but important anomaly. Prenatal diagnosis is possible with knowledge of the distinctive imaging features. The purpose of this case series is to illustrate characteristic prenatal sonographic and magnetic resonance imaging features of cloacal malformation using imaging from 6 cases seen at a single academic center to augment published data. The imaging feature common to all cases was a central cystic pelvic mass containing a characteristic fluid‐fluid level. Additional anomalies include uterine and vaginal duplication, hydronephrosis, and lumbosacral anomalies. Prenatal magnetic resonance imaging showed the absence of the normal T1‐hyperintense meconium‐filled rectum in all cases. Prenatal diagnosis may affect immediate neonatal care (eg, immediate drainage of hydrocolpos) with an ultimate improved outcome.