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D Vadrot

Publications and source records attributed to D Vadrot.

At least 19 recordsLinked to original sources

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.

Adult

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.

Adult

[Value of CT scan and MRI in primary tumors of the ovary].

Characterisation of an ovarian mass is of utmost importance in the preoperative evaluation of an ovarian neoplasm. It enables the surgeon to anticipate carcinoma of the ovary before the operation, so that adequate procedures are planned. Although, ultrasonography (US) remains the foremost imaging modality for screening patients with adnexal lesions, computed tomography (CT) recently has proved to be of value in the characterisation and management of tumors of the ovary. Magnetic resonance (MR) imaging has also been shown to have a high degree of diagnostic specificity for certain types of ovarian masses, such as dermoid cysts, and endometriomas. However, the potential of MR imaging to characterize tumors of the ovary has not yet been established. This study assesses the value of MR imaging and CT for the purpose of predicting the malignancy of ovarian lesions, and comparing findings of MR imaging with those of CT.

Brenner Tumor

Focal hyperdense areas in endometriomas: a characteristic finding on CT.

OBJECTIVE: To assess the value of a hyperdense focus seen on CT scans of endometrial cysts in the differential diagnosis of a lesion. MATERIALS AND METHODS: The preoperative CT scans of 328 patients with 410 ovarian masses (54 patients with 62 pathologically proved endometriomas and 274 patients with 348 pathologically proved other ovarian masses) were retrospectively reviewed in a random fashion without knowledge of the pathologic findings to determine whether a hyperdense focus was visible inside a cyst. RESULTS: In nine of 62 endometrial cysts (sensitivity, 15%), CT scans showed a hyperdense round or crescent-shaped focus, measuring 2 to 15 mm. This focus was located close to the inner border of the cyst in eight cases and in the central part of the cyst in one case. A hyperdense focus was not seen on CT scans of 348 other ovarian masses (specificity, 100%). An in vitro CT study of two specimens showed that this hyperdense area corresponded to a blood clot next to the inner wall of the cyst. This hyperdense area appeared as a nonspecific hyperechogenic focus on sonograms in five of nine cases and as a hypointense signal on T1- and/or T2-weighted MR images in four of five cases. CONCLUSION: The finding on CT scans of a hyperdense focus inside an ovarian cyst is suggestive of endometrioma and should help distinguish endometrioma from other pelvic masses.

Carcinoma

[Contribution of echogradient magnetic resonance imaging in the study of subacromial diseases. Surgical and arthrographic correlations].

Fifteen asymptomatic volunteers and 300 patients with suspected lesions of the rotator cuff were examined with T2*- and proton density-weighted gradient echo (T2*-Rho-GEI) MRI sequences (500-700 ms/30 ms/30 degrees) with a 0.5 T (GE-CGR) system and an adapted surface coil. For the patients, the findings were compared with those of arthrography in 130 cases and of surgery in 42 cases. For the operated patients, T2*-Rho-GEI and arthrography allowed correctly diagnosing 31 complete ruptures (CR). However, surgical exploration of the ruptures showed that T2*-Rho-GEI showed the actual extent of the rupture and the degree of tendon retraction better than arthrography. T2*-Rho-GEI also provides information about the thickness and trophicity of the remaining cuff and on local muscle trophicity. T2*-Rho-GEI allows directly evaluating the tendon of the long head of the biceps both in its extra-articular and its intra-articular parts. In 3 cases of complete cuff rupture, MRI allowed detecting 3 associated lesions of the anterior labrum, which had not been suspected on the clinical examination and had not been demonstrated by conventional arthrography. Lastly, out of 12 cases of deep incomplete rupture (n = 12) correctly diagnosed with MRI, 5 had been undetected on arthrography. Similarly, 8 cases of inflammatory alterations suspected with T2*-Rho-GEI and confirmed by surgery had not been recognized with arthrography. For the non-operated patients, T2*-Rho-GEI and arthrography had corresponding results for the diagnosis of CR (8 cases), of DIR (6 cases) and of intact cuff (6 cases).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

Comparison of magnetic resonance imaging and computed tomography in the preoperative staging of rectal cancer.

Nineteen patients with middle and lower rectal carcinomas were operated on, with abdominoperineal resection in 10 patients, lower anterior resection with coloanal anastomosis in 6 patients, and colorectal anastomosis in 3 patients. The distance of the lower margin of the tumor to insertion of the levator ani on the rectal wall was correctly evaluated by computed tomography in 12 (63%) of 19 patients and by magnetic resonance imaging in 13 (68%) of 19 patients, while digital examination correctly assessed the distance in 15 (79%) of 19 patients. Computed tomography and magnetic resonance imaging were unable to assess extension through the rectal wall. No significant difference was observed between computed tomography and magnetic resonance imaging in assessing extension to the perivesical fat, adjacent organs, pelvic side wall, or lymph nodes. According to the TNM classification, magnetic resonance imaging correctly staged 74% (14/19) of carcinomas, while computed tomography correctly staged 68% (13/19).

Aged

[Comparative study of MRI and x-ray computed tomography in the preoperative evaluation of rectal carcinoma].

Twenty-one patients with middle and low rectal carcinomas have been operated by abdominoperineal resection (APR) in 11 patients, and low anterior resection (LAR) with coloanal anastomosis in 7 and colorectal anastomosis in 3. The distance of the lower margin of the tumor to insertion of the levator ani on the rectal wall was correctly evaluated by CT in 15 of 21 cases (71%) and by MR in 14 of 21 (67%) while digital examination correctly assessed the distance in 17 of 21 (81%). CT and MR were unable to assess extension through the rectal wall. No significant discordance was observed between CT and MR in assessing extension to the perivesical fat, adjacent organs, pelvic side wall or lymphnodes. According to the TNM classification, MR correctly staged 76% (16 of 21) of patients while CT correctly staged 71% (15 of 21).

Adenocarcinoma

[Rapid imaging in orbito-ocular pathology. Contribution of gadolinium].

To evaluate Gradient-Echo Imaging (GEI) in orbito-ocular pathology, 15 volunteers and 34 patients (40 lesions) were examined with GEA T1 and GEA T2 (0.5 T). Results were compared with SE T1 in all cases, with SE T2 in 20 cases and with other imaging modalities (CT). 30 patients were examined before and after injection of gadolinium. Final diagnosis was obtained by surgery or biopsy in 24 cases or by combined results of imaging and clinical findings in 16 cases. Compared with SE, GEA demonstrated a better visualisation of optic nerve, orbital muscles, choroidal-retinal layer, lens capsule and episclera and a better detection of small lesions. It is very helpful for characterisation of lesions containing hemorrhages or paramagnetic components (melanine, gadolinium) or of vascular nature (angioma). Gadolinium was useful for detection of small lesions or characterisation of a few lesions. Thus GEA seems to be an efficient method for the evaluation of orbito-ocular pathology.

Adolescent

[Pulmonary hemorrhage complicating transthoracic puncture].

Fine needle transthoracic aspiration (FNTA) of pulmonary opacities under guidance of computerized tomography (CT) is a simple procedure yielding conclusive results in many patients with malignant lung tumours. The small caliber of the needles utilized and the CT control make this increasingly popular procedure both accurate and safe. Yet a number of complications have occurred; most of them were benign (e.g. pneumothorax) but some were potentially dangerous (e.g. pulmonary haemorrhage), so that the pros and cons of the procedure must carefully be weighed. We report the case of a patient in whom FNTA was complicated by copious haemoptysis and a pulmonary haematoma clearly visible at CT. The literature concerning the potential complications of transthoracic puncture is reviewed.

Aged

[X-ray computed tomographic aspects of dermoid cysts of the ovary].

155 patients with 210 ovarian tumours were examined pre-operatively by CT from December 1984 to February 1988. 27 patients had dermoid cysts, unilateral in 25 cases and bilateral in 2 cases. These cystic teratomas were benign in 26 patients. In one case, malignant transformation occurred. CT detected 29/29 tumours (100%). Presence of fat (26/29, 90%), calcification (20/29, 69%), Rokitansky protuberance (25/29, 86%), tufts of hair (20/29, 69%), or fat fluid level (4/29, 14%), allowed to make a definite diagnosis in 28/29 cases (96%). These findings and especially demonstration of fat, appeared to be specific for dermoid cysts in our series. The diagnosis of torsion of the cyst associated with torsion of the adnexa was made in 2 patients. No abdomino-pelvic extension occurred in 26/26 patients presenting with a benign dermoid cyst and CT correctly diagnosed the lymph node and hepatic spread in the single case of cancer.

Adolescent

[Contribution of MRI in the staging of cancer of the bladder. Apropos of 40 cases].

56 patients with bladder carcinoma were examined by magnetic resonance in the pre-operative staging. In 40 patients where total cystectomy with enterocystoplasty and pelvic node dissection were performed, a good correlation with surgical and pathologic findings was obtained. MR examination using T1 (TR 400 ms, TE 28 ms) and T2 (TR 1,200-1,600 ms, TE 40 80 120 ms) weighted images in different planes where performed after biopsy of the bladder tumor through endoscopy and within 1 or 2 weeks before surgery. Neoplasms were characterized by site, size and growth pattern. Extension through the deep muscle of the bladder wall was correctly identified in 95% with a sensitivity of 95% and a specificity of 95%. Extension through perivesical fat was assessed accurately in 85% with a sensitivity of 66% and a specificity of 100%. Accuracy in evaluating invasion of adjacent organs was 85%, sensitivity 44%, specificity 96%. Lymphadenopathy has been accurately assessed in 97.5% with a sensitivity of 83% and a specificity of 100%. MR correctly staged the tumor according to TNM classification in 24/40 (60%) patients, overestimated the extension in 3/40 (7.5%) and underestimated the extension in 13/40 (32.5%).

Adult

Peritoneal implants from ovarian tumors: CT findings.

Metastatic peritoneal implants were assessed preoperatively with computed tomography (CT) in 38 patients with ovarian tumors. In the 106 biopsy specimens of gross peritoneal implants and the 118 random biopsy specimens obtained from these patients, metastatic deposits were detected in 27 of 38 (71%) patients and in 104 biopsy sites. CT depicted metastatic lesions in 17 of 27 (63%) patients and in 63 of 104 (61%) biopsy sites. The three sites most commonly involved were the right subphrenic region, the greater omentum, and the pouch of Douglas. The usefulness of CT in detecting lesions depended mainly on the location of the implant and the presence of adjacent ascites, rather than on lesion size.

Adult

MR staging of bladder carcinoma: correlation with pathologic findings.

Forty patients with bladder carcinoma were examined preoperatively by means of magnetic resonance (MR) imaging. In all patients, total cystectomy with enterocystoplasty and pelvic node dissection was performed. The surgical and pathologic findings were correlated with the MR findings. Extension through the deep muscle of the bladder wall was present in 20 of the 40 patients and was diagnosed with a sensitivity of 95% and a specificity of 95%. Extension to perivesical fat was present in 18 of 40 patients and was diagnosed with a sensitivity of 66% and a specificity of 100%. Invasion of the adjacent organs was present in nine of 40 patients and was diagnosed with a sensitivity of 44% and a specificity of 96%. On the basis of the MR findings, the tumor was correctly staged, according to the TNM classification, in 24 of 40 (60%) patients, tumor extension was overestimated in three of 40 (7.5%) patients, and tumor extension was underestimated in 13 of 40 (32.5%) patients. MR imaging has been shown to be accurate in identification of macroscopic lymph node involvement and deep muscle involvement. It appears to be at least as useful as computed tomography (CT) in the evaluation of perivesical fat involvement and to be superior to CT in the detection of invasion of adjacent organs. One limitation of MR imaging is in the evaluation of tumor extension into the periurethral glands.

Adenocarcinoma

[Castleman's disease. X-ray computed tomographic aspect. Apropos of 2 mediastinal forms and a multicentric form].

A multicentric form of Castleman's disease is described, this being a rare affection for which CT image characteristics have not, to our knowledge, been reported. Two cases of localized and one case of multicentric Castleman's disease are reported, and differential characters of these two forms with common histology: angio-follicular lymphoid hyperplasia, outlined. The localized form is found mainly in the mediastinum in young patients and follows a favorable course with recovery after exeresis. The diffuse form develops in later life and presents with severe systemic signs and a marked biological inflammatory syndrome Glands and viscera are affected and its course is grave, with mostly fatal relapses. Angiography suggests diagnosis when images show hypervascular lesions in lymph glands. CT scan imaging with contrast is very suggestive when glandular lesions are present that take up contrast strongly. This appearance should always raise the possibility of Castleman's disease.

Adult