PubMed Health⌕ Search

Biomedical subjects

N Rocourt

Publications and source records attributed to N Rocourt.

15 recordsLinked to original sources

[Magnetic resonance imaging applications in obstetrics].

PURPOSE: To review the main indications and results of magnetic resonance imaging in the pregnant women. MATERIAL AND METHOD: We reviewed MRI practice during the pregnancy based on our own experience in a prenatal diagnostic center and data in the literature. Rapid improvement in MRI technology has allowed more extensive use, giving a good contrast-to-noise ratio and multiplanar imaging. RESULTS: Although ultrasound provides primary screening information, final diagnosis may require further investigations. MRI, to be performed in the second and third trimester, is the non-invasive second line tool of choice in this context. The most widespread indications are for brain disease: search for a cause of ventriculomegaly or biometric abnormality, confirmation of a malformative or acquired lesion. Progressively, indications were widened to head and neck, thorax, abdomen and pelvis areas. Moreover, systematic indications include previous fetal pathology or the pregnancy context. Other MRI indications have been suggested: placental malposition, pelvimetry and maternal genito-urinary tract. CONCLUSION: MRI is becoming the natural and necessary second line imaging technique, with increasing indications. It must be kept in mind however that all pathological conditions cannot be depicted by these morphological studies.

Congenital Abnormalities↗

[Cerebral fetal MRI and ventriculomegaly].

OBJECTIVE: To evaluate MRI usefulness in diagnosis and management of fetuses with cerebral ventriculomegaly at US. PATIENTS AND METHODS: Sonography depicted cerebral ventriculomegaly in 61 fetuses. Management included MRI in all cases and infectious screening, and karyotype in 51 cases. Final diagnosis was supported by fetal autopsy (n=24), postnatal follow-up>6 months (n=19), infectious screening or karyotype (n=8), and MR imaging when diagnosis was obvious (n=16). RESULTS: MRI was more informative than ultrasonography in 32.8% of cases with identification of the etiology in 21.3% of cases. In 45% MRI and sonography were considered to be normal. In the remaining cases, MRI confirmed the ultrasound diagnosis of cerebral malformation. Ultrasonography never depicted more anomalies than MR imaging. The 2 false negatives were gyration disorders but MR imaging was performed too early. CONCLUSION: US is the imaging modality of choice in the evaluation of fetal anomalies but MRI has to be systematically performed in case of cerebral ventriculomegaly because MRI demonstrates its usefulness in patient counseling, even if there are a few false negative results.

Abortion, Therapeutic↗

[MRI in gynecology].

OBJECTIVES: To review the complementary role and contribution of magnetic resonance imaging (MRI) in gynecology diseases. RESULTS: Tissue characterization can be obtained with T2, T1 weighted images before and after contrast medium injection and T1 fat sat sequences. Localization of the lesion and relationships with adjacent structures are facilitated by multiplanar imaging. Endometrium and ovarian follicles display high signal intensity, visualizing the normal uterine and ovarian components. The relative high signal intensity of uterine tumors facilitates evaluation of extension. Uterine leiomyoma diagnosis is supported by its low signal intensity, allowing localization, size, and number assessment, and to distinguish adenomyoma. In doubtful malformation cases, MRI may be contributive. Ovarian mass characterization can be done with MRI, particularly for dermoid cyst and endometrioma. In this case, deep endometriosis can be associated and be extensive. Recent technical advances enable fast imaging, which can be useful for pelvic floor assessment with dynamic evaluation. CONCLUSION: MRI is becoming the complementary reference imaging tool for us. Its increasing indications are: gynecologic cancer, pelvis endometriosis, pelvis floor, indeterminate pelvis mass and fibroleiomyoma.

Endometriosis↗

Assessment of Fallopian tube patency by HyCoSy: comparison of a positive contrast agent with saline solution.

OBJECTIVE: To compare the efficiency of air-filled albumin microspheres (Infoson) with saline solution in determining Fallopian tube patency during hysterosalpingo contrast sonography (HyCoSy). METHODS: This was a prospective randomized multicenter study with a sequential design. Over a 10-month period, 23 patients (mean age, 33 years) referred for infertility were examined by HyCoSy (saline or Infoson) before conventional hysterosalpingography (Iopamiron 370), performed during the same session. Contrast agents were administered through a 5-F Ackrad balloon catheter inserted transcervically into the uterine cavity. HyCoSy was performed with a 7-MHz transvaginal probe using both B-mode and color Doppler, and tubal patency was demonstrated by the appearance of contrast agent in the peritoneal cavity near the ovaries. Data were registered for each patient during the examination and the results were monitored by sequential analysis. RESULTS: Mean volumes of contrast injections were 35.3 mL of saline, 14.4 mL of Infoson, and 13.8 mL of Iopamiron 370. Infoson-enhanced HyCoSy provided a significantly larger (P = 0.006) number of correct diagnoses (20/22 Fallopian tubes) than did saline HyCoSy (12/24 Fallopian tubes), and the same number as that achieved by hysterosalpingography. CONCLUSION: A positive ultrasound contrast agent appears to be more efficient than saline solution at determining Fallopian tube patency in infertile women by means of HyCoSy, and as efficient as an iodinated contrast agent in the same population explored by HSG. HyCoSy could be used to screen infertile women, thereby avoiding the use of iodinated contrast medium and exposure to ionizing radiation during conventional HSG in patients with patent Fallopian tubes.

Adult↗

Fetal lung volume: estimation at MR imaging-initial results.

PURPOSE: To plot normal fetal lung volume (FLV) obtained with fast spin-echo magnetic resonance (MR) images against gestational age; to investigate the correlation between lung growth and fetal presentation, sex, and ultrasonographic (US) biometric measurements; and to investigate its potential application in fetuses with thoracoabdominal malformations. MATERIALS AND METHODS: In a prospective multicenter study, 336 fetuses suspected of having central nervous system disorders underwent fast spin-echo T2-weighted lung MR imaging. Data obtained at 21-38 weeks gestation in 215 fetuses without thoracoabdominal malformations and with normal US biometric findings were selected for an FLV normative curve. FLV measurements obtained at pathologic examination with an immersion method were compared with MR FLV measurements in 11 fetuses. MR FLV values in 16 fetuses with thoracoabdominal malformations were compared with the normative curve. RESULTS: Normal FLV increased with gestational age as a power curve; the spread of values increased with age. Interobserver correlation was excellent (R(2) = 0.96). FLV measurements at MR imaging were 0.90 times those at pathologic examination. A constant ratio (0.78) between FLV on the left and right sides was observed. No significant difference in FLV was observed between fetal presentations. Normal FLV was observed in all fetuses with cystic adenomatoid malformations and in four of six with oligohydramnios. Lowest FLV values were observed in fetuses with diaphragmatic hernia. CONCLUSION: In fetuses with normal lungs, FLV distribution against gestational age is easily assessed in utero with fast spin-echo T2-weighted MR imaging. These preliminary findings illustrate the potential for comparing FLV measurements in fetuses at risk of lung hypoplasia with normative values.

Abnormalities, Multiple↗

[Imaging of the endometrium].

During genital activity, physiological and pathological modifications can be observed; Pre- and postmenopausal menometror-rhagia are the principle clinical signs of various endometrial pathologies: benign (polyp, atrophy or endometrial hypertrophy), malignant (cervical or endometrial carcinoma) or neighboring pathologies (myometrium or ovary). The value and methods of various imaging techniques (B-mode and Doppler abdominal and endovaginal ultrasonography, hysterosonography, computed tomography, MR imaging and hysteroscopy) are described together with symptomatological features permitting identification of the endometrial pathology.

Endometrium↗

[Cystic ovarian pathology excepting genital activity].

Ovarian size progressively increases in infancy, from 2cm to more than 3cm in length during the hormonal stimulation which occurs during the pubertal stage. The presence of ovarian follicules is a normal finding whatever the age; the presence of multifollicular ovaries is common during the pubertal stage. In the neonatal stage, marked by the maternal hormone influences, a cystic mass must be considered as an ovarian cyst whatever the location, abdominal or pelvic. Hemorrhagic ovarian cysts with a solid and heterogeneous pattern are frequent. In the pre and peripubertal stages, it is important to recognize functional ovarian cysts, which are common, fluid filled, variable in size from 3 up to 8cm. No treatment is generally required and a number of these cysts spontaneously resolve. Organic cysts of the ovary are rare in adolescence and infancy. The most frequent germ cell tumor is the cystic dermoid or mature teratoma. In the menopausal stage, the questions arise differently: complex cysts (thick wall, septae, heterogeneous structure) require surgical advice; simple cysts, both fluid filled and unilocular, require follow up if less than 3cm, a puncture from 3 to 5cm, and a surgical procedure when greater than 5cm.

Adolescent↗

[Ovarian functional disorders].

Ovarian hormonal function is under hypothalamo-hypophysis control during the genital life of women. Local hormonal production induces follicular stimulation and maturation. Two main types of functional disorder can be observed: unilocular cyst, related to an ovulation mechanism, and polycystic ovaries. The former is a follicular cyst related to the absence of LH stimulation, or a luteal cyst, which may be anechoic or display a heterogeneous content (pseudo-septa, pseudo-solid but avascular mass). The latter includes the polycystic ovarian syndrome, which is characterized by an increased ovarian area ( 6cm(2)), stroma and follicles number, the multifollicular ovaries, which are related to functional hypothalamic anovulation and characterized by a normal ovarian size with increased follicles number, and macropolycystic ovaries which are observed in case of previous pelvic infection disease or surgery. Functional disorders may be observed during pregnancy: luteoma, luteal cyst and hyperreactio luteinalis. Finally, ovarian insufficiency may occur too early.

Female↗

[Ultrasonic diagnosis of placenta percreta. Apropos of a case with hemorrhagic complication].

Placenta percreta is a rare but severe disease, which is more and more frequent. The reported case shows that diagnosis can be made with B mode and color Doppler ultrasonography. Extension of high-vascularized placenta to the myometrium, abnormal placental-subplacental complex and vascular flow through the myometrium were suggestive of the diagnosis. Early diagnosis should decrease mortality and morbidity.

Adult↗

Helical CT of the larynx: a comparative study with conventional CT scan.

AIM: To compare helical and conventional CT scans of the larynx. PATIENTS AND METHODS: Thirty-three patients underwent helical and conventional CT studies of the neck and the larynx using 3 mm section collimation for both studies and a table feed of 4 mm/sec for helical CT. Helical scans were reconstructed at 2 mm increments. Two independent observers rated the visibility of the laryngeal structures from 1 (poor and non diagnostic) to 5 (excellent and diagnostic), and motion artifacts from 1 (> or = 10 degraded scans) to 5 (no motion artifacts). RESULTS: The motion artifacts score was significantly better for helical CT. No significant difference was observed for the laryngeal structures score between helical and conventional CT studies. The interobserver kappa mean value was 0.756 and 0.68 for helical and conventional CT, respectively. CONCLUSION: Helical CT can be routinely performed and replace conventional CT study for the evaluation of laryngeal diseases.

Adult↗

Congenital cholesteatoma of the temporal bone: MR findings and comparison with CT.

PURPOSE: To describe the MR findings of temporal bone congenital cholesteatoma and MR usefulness in preoperative diagnosis and follow-up, in comparison with CT. METHODS: Seven patients underwent CT and MR studies for facial palsy (n = 3), deafness (n = 3), vertigo (n = 1), tinnitus (n = 1), and otalgia (n = 1). Three patients had for congenital cholesteatoma previously undergone surgery. One of them was free of symptoms and referred for follow-up. Final diagnosis was obtained from surgical data in all the cases but one. RESULTS: Congenital cholesteatoma signal intensity was low or intermediate on T1-weighted images and high on T2-weighted images in all the cases. MR was useful in diagnosis in six cases, helping to differentiate congenital cholesteatoma from other nonenhancing tumors. When temporal bone wall erosion was observed with CT (n = 6), MR ruled out intracranial extension in five cases; in one case, MR found an associated epidermoid cyst of the cerebellopontine angle not identified with CT. However, CT assessed relationships with labyrinthine structures more easily. CONCLUSION: MR and CT are complementary in initial diagnosis and follow-up.

Adolescent↗

Serial anatomy of the auditory tube: correlation to CT and MR imaging.

Serial anatomy of the auditory tube (AT), was studied in nine anatomical specimens, according to transverse, coronal and specific oblique planes and was correlated to computed tomography and magnetic resonance imaging. In order to assess the orientation of the oblique plane, parallel to the AT, 30 AT specimens were catheterized: the mean angle between the AT and the Virchow plane or the bony palate was 34 degrees. The bony portion is better explored with CT, whereas the cartilaginous portion is better studied with MR. The cartilage, posterior and medial, is closed anteriorly and inferiorly by a fibrous membrane (lamina membranacea), which is not seen on CT or MR images. The AT is closely related to the tensor veli palatini muscle (TVPM) anterolaterally, and the levator veli palatini muscle inferiorly (LVPM); both are well imaged on the oblique plane. They are bounded by fascias: the submucosal fascia (tela submucosa) is medial, the pharyngobasilar fascia runs between the TVPM and the LVPM and the auditory tube; the fascia of Weber-Liel is lateral to the TVPM. Fascias are difficult to distinguish from the surrounding fatty tissue and the adjacent muscles. The auditory tube and its muscles, forming the lateral wall of the nasopharynx, are well studied by CT and MR imaging, using the transverse or, preferably oblique plane, together with coronal plane.

Eustachian Tube↗

MR findings of ejaculatory duct cysts.

Ejaculatory duct cysts are a rare type of prostatic cysts. We report 3 cases of symptomatic ejaculatory duct cysts which have been explored by MR imaging. The MR findings were round or oval masses, medial or paramedial in the prostatic gland above the level of the verumontanum, extending into the prostatic base. They displayed a low signal intensity on T1-weighted images and high signal intensity on T2-weighted images (2 cases) or high signal intensity on both T1- and T2-weighted images (1 case). The diagnosis was confirmed by an ultrasonographically guided transperineal aspiration demonstrating spermatozoa in the cyst fluid.

Adult↗