Dominique Vadrot

Fibrothecomas of the ovary : CT and US findings

Objective Fibrothecomas of the ovary are mesenchymal tumors representing 4–5% of all ovarian neoplasms. The purpose of this study is to describe a large series of CT findings in this type of tumor. Materials and Methods We reviewed retrospectively the CT examinations in 25 unilateral cases confirmed by surgery and pathology. Unenhanced and enhanced CT scans were performed in all cases and dynamic CT scans were performed in nine cases. These findings were compared to ultrasound in all cases. Results Computed tomography detected all but two small ovarian tumors (<2 cm). Eighteen of 23 fibrothecomas were solid, with significant (>10 HU) enhancement between precontrast and delayed CT scans. In all eight uncomplicated cases, nonincremental dynamic CT scan did not visualize arterial vessels; in seven of nine cases examined dynamically, early uptake of contrast material was visualized. Three of 23 fibrothecomas were partly cystic, partly solid. Two cases with torsion were mainly cystic with thickening and hemorrhage of the tube. Conclusion In conclusion, 79% of ovarian fibrothecomas appeared as solid masses with delayed accumulation of contrast medium. On dynamic CT, the absence of arterial vessels and absence or slight early uptake of contrast enhancement could be useful findings for preoperative diagnosis. When partly or mainly cystic (21% of cases), ovarian fibrothecomas could not be easily differentiated from other ovarian masses.

CT in adnexal torsion with emphasis on tubal findings : correlation with US

Objective Our goal was to determine the CT and US aspects of the fallopian tube in adnexal torsion. Materials and Methods The CT scans and US studies of 10 patients with surgically proven unilateral torsion of the adnexa were reviewed. Results On CT the fallopian tube on the involved side was identified in eight cases as an almost tubular or comma-shaped structure extending from the uterine cornua and covering partially the adnexal mass. This tube was significantly thickened and measured 20–40 mm. Hemorrhage (density ≥50 HU on precontrast CT scans) was present in the tube in six patients. A heterogeneous contrast agent uptake was detected in the tube in five patients. An adnexal mass was visualized on the involved side in all patients, with hemorrhage in the mass in four patients. Peritoneal fluid and/or ileus were present in six patients. On US an echogenic structure that corresponded to the enlarged tube visualized on CT was detected in three cases and an adnexal mass in all cases. Conclusion Thickening of the fallopian tube with hemorrhage could be detected by CT and is suggestive of torsion especially if associated with an adnexal mass.

Preoperative assessment of the extension of rectal carcinoma: correlation of MR, surgical, and histopathologic findings.

Nineteen patients with rectal carcinoma were evaluated prospectively. The extent of tumor and the relationship of the tumor to the levator ani muscle were studied as this determines the choice of the surgical procedure (abdominoperineal resection versus low anterior resection). Peroperative assessment and detailed evaluation of the pathologic specimens were correlated with magnetic resonance (MR) features. Magnetic resonance staging and surgical findings were at variance in four of 15 cases (27%). Magnetic resonance had sensitivities and specificities of 75 and 100% in the detection of perirectal growth. Magnetic resonance demonstrated invasion of adjacent pelvic side wall and sacrum in two of two cases. The comparison with TNM classification demonstrated that MR correctly staged 15 of 19 cases (79%). This study shows that MR is a good examination to evaluate the involvement of perirectal fatty tissues and adjacent structures. The low prevalence of involved lymph nodes in our cases prevents significant positive predictive values. Nevertheless, MR can help to select patients for local excision or for preoperative radiotherapy.

Mature cystic teratomas of the ovary: CT and MR findings

OBJECTIVE To correlate CT and MR patterns of ovarian mature cystic teratomas (MCT). SUBJECTS AND METHODS CT and MR findings in 25 histologically proven ovarian MCT were retrospectively reviewed. MCT characterization at CT and MR was based on detection of fat and/or a Rokitansky protuberance. MR signal intensity and CT density numbers of fat were correlated. RESULTS At pathology, 24/25 tumors contained fat, 1/25 a water content, and 23/25 a Rokitansky protuberance. Twenty one MCT contained fat with a density number less than-20 HU (mean density: -95 HU) and a signal intensity superior or equal to sub-cutaneous fat on T1 images, however, only six of these had a signal intensity equal to sub-cutaneous fat on T1 and T2 images and 12 had a reversed chemical shift artifact. Three contained fat with a density number ranging from -13 to +8 HU and a signal intensity inferior to subcutaneous fat on T1 images. CT showed a Rokitansky protuberance in 21/23, containing adipose tissue in 16 and calcified structures in 21. Standard MR showed a Rokitansky protuberance in 14/23 and characterized adipose tissue in eight cases, and calcified material in six cases. Finally, CT characterized 24/25 (96%) MCT. Standard MR characterized 22/25 (88%) MCT, and standard MR with fat-suppression sequences characterized 23/25 (92%) MCT. CONCLUSION Standard MR is less effective than CT in characterizing fat and has the same difficulty as CT in characterizing fat mixed with hair when its density is high. When fat cannot be identified by either technique, diagnosis of a Rokitansky protuberance is more easily made at CT than at MR.

Computed tomography of mediastinal lymph nodes in nonsmall cell lung cancer: a new approach based on the lymphatic pathway of tumor spread

Computed tomography was used to evaluate mediastinal lymph nodes in 97 patients with nonsmall cell lung cancer. All patients had thorough surgical-pathological determination of mediastinal node status. Twenty-three patients were found to have metastatic lymph nodes. The usual lymphatic pathways of tumor spread into the mediastinum were defined using the node mapping scheme suggested by the American Thoracic Society. We considered mediastinal nodes abnormal when the short axis of the largest mediastinal node in the lymphatic drainage territory of the cancer was greater than or equal to 10 mm and the difference between this node and the largest node in the other territories is greater than 5 mm. The sensitivity was 78%, the specificity 99%, the positive predictive value 95%, the negative predictive value 94%, and the accuracy 94%. Comparing our method to those that used the size criterion alone, the number of false positives was reduced.

Fat suppression techniques in MR imaging of mature ovarian teratomas: comparison with CT

OBJECTIVE The aim of this study is to analyze the ability of MR fat suppression techniques to characterize fat components of ovarian mature cystic teratomas (MCT) shown by CT. SUBJECTS AND METHODS MR images of eight MCTs of the ovary were obtained using standard sequences followed by a SPIR (spectral presaturation with inversion recovery) sequence in six cases and by Dixon sequences in two cases. In all cases correlation with CT and pathologic findings was achieved. RESULTS MR fat suppression sequences showed to be as accurate as CT in detecting fat inside the cystic part of the teratomas (8/8). CONCLUSION MR fat suppression sequences should be performed when presence of fat is suspected on images of ovarian tumors produced by standard MR sequences.

Swyer-James syndrome documented by spiral CT angiography and high resolution inspiratory and expiratory CT: an accurate single modality exploration.

Spiral CT angiography was performed in a patient suspected of having pulmonary embolism. The right pulmonary system was normal. The left arterial system was small but patent. The left upper lobe was small and hyperlucent. The left lower lobe was collapsed and contained bronchiectasis. The bronchi were patent. High resolution CT in inspiration and expiration confirmed air trapping in the left upper lobe. A diagnosis of Swyer-James syndrome of the left upper lobe was made.

Characterization of Papillary Projections in Benign Versus Borderline and Malignant Ovarian Masses on Conventional and Color Doppler Ultrasound

OBJECTIVE The purpose of our study was to evaluate on endovaginal ultrasound the morphologic and color Doppler characteristics of papillary projections in benign compared with borderline and malignant epithelial stromal ovarian tumors. MATERIALS AND METHODS A total of 283 women (mean age, 52 years; age range, 20-85 years) with 343 operated adnexal masses comprising 167 epithelial stromal tumors of the ovary with 76 tumors containing papillary projections at pathology were retrospectively studied on ultrasound. We systematically evaluated the topography of the papillary projections, the morphologic features of the largest papillary projection, and the presence or absence of color Doppler findings. All these findings were correlated with macroscopic and microscopic features. RESULTS Ultrasound detected papillary projections in 78% of tumors. Papillary projections were disseminated in 33% of malignant, 20% of borderline, and 0% of benign tumors (p = 0.0049). The mean size of the papillary projections was 9.6, 15.7, and 35.3 mm in benign, borderline, and malignant tumors, respectively (p = 0.0007). An acute angle was present in 68% of benign tumors and an obtuse angle in 40% of borderline and 89% of malignant tumors (p = 0.0001). The surface was regular in 77% of benign tumors and irregular in 50% of borderline and 88% of malignant tumors (p = 0.0000). Calcifications were present only in benign tumors (18%). For papillary projections ≥ 10 mm, color flow was present in all malignant, in 86% of borderline, and absent in all benign tumors. CONCLUSION Association of morphologic and vascular ultrasound findings can highly suggest the diagnosis of benign or malignant papillary projection.

In vivo visualization of the levator ani muscle subdivisions using MR fiber tractography with diffusion tensor imaging

Understanding the levator ani complex architecture is of major clinical relevance. The aim of this study was to determine the feasibility of magnetic resonance (MR) fiber tractography with diffusion tensor imaging (DTI) as a tool for the three‐dimensional (3D) representation of normal subdivisions of the levator ani. Ten young nulliparous female volunteers underwent DTI at 1.5 T MR imaging. Diffusion‐weighted axial sequence of the pelvic floor was performed with additional T2‐weighted multiplanar sequences for anatomical reference. Fiber tractography for visualization of each Terminologia Anatomica‐listed major levator ani subdivision was performed. Numeric muscular fibers extracted after tractography were judged as accurate when localized within the boundaries of the muscle, and inaccurate when projecting out of the boundaries of the muscle. From the fiber tracking of each subdivision the number of numeric fibers (inaccurate and accurate) and a score (from 3 to 0) of the adequacy of the 3D representation were calculated. All but two volunteers completed the protocol. The mean number of accurate fibers was 17 ± 2 for the pubovisceralis, 14 ± 6 for the puborectalis and 1 ± 1 for the iliococcygeus. The quality of the 3D representation was judged as good (score = 2) for the pubovisceralis and puborectalis, and inaccurate (score = 0) for the iliococcygeus. Our study is the first step to a 3D visualization of the three major levator ani subdivisions, which could help to better understand their in vivo functional anatomy.