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Laurent J Salomon

Publications and source records attributed to Laurent J Salomon.

12 recordsLinked to original sources
PubMed2006

Placental perfusion and permeability: simultaneous assessment with dual-echo contrast-enhanced MR imaging in mice.

PURPOSE: To assess placental perfusion and permeability in mice with magnetic resonance (MR) imaging. MATERIALS AND METHODS: This study was conducted according to French law and National Institutes of Health recommendations for animal care. Twenty-two pregnant BALB/c mice were examined at 1.5 T with a single-section dual-echo fast spoiled gradient-echo sequence. Two injection protocols were used: monophasic injection (double the clinical dose of contrast agent) and biphasic injection (quadruple the clinical dose). Signal intensities (SIs) were measured in the maternal left ventricle, placenta, and fetus (n = 16). At these high gadolinium doses, a T2* effect correction was used. SIs were converted to gadolinium concentrations and were analyzed by using a three-compartment model. Quantitative microcirculation parameters were calculated. Results with the monophasic and biphasic protocols were compared, and final arterial concentrations determined with MR imaging were compared with those determined with atomic emission spectrophotometry by using the unpaired Student t test. RESULTS: Perfusion and permeability parameters for monophasic and biphasic injections were similar: Mean placental blood flow was 180 mL/min/100 g, mean permeability surface coefficient from maternal placental to fetal placental compartment was 10.3 x 10(-4) sec(-1) +/- 6.81 (standard deviation), mean permeability surface coefficient from fetal placental to maternal placental compartment was 4.65 x 10(-4) sec(-1) +/- 4.37, and mean fractional volume of the maternal vascular placental compartment was 36.5% +/- 0.9. Placental (146 vs 105 micromol/L, P < .004) and fetal (33.3 vs 19.1 micromol/L, P < .001) gadolinium concentrations were higher with the biphasic than with the monophasic protocol. Arterial gadolinium concentrations at MR imaging did not differ significantly from those at spectrophotometry for the monophasic (P = .254) or biphasic (P = .776) injection protocol. CONCLUSION: Placental perfusion and permeability can be measured in vivo by using high gadolinium doses and a dual-echo MR imaging sequence.

Animals↗
PubMed2006

Abnormal abdominal situs: what and how should we look for?

BACKGROUND: Prenatal management of abnormal abdominal situs is challenging since prognosis is highly variable depending on the associated malformations. METHODS: The authors report on two cases of ambiguous abdominal situs. Prenatal management included specialized ultrasound examination of fetal anatomy and heart, amniocentesis for determination of the fetal karyotype and fetal abdominal MR. RESULTS: In both cases, abnormal situs was associated with other abdominal anomalies such as azygous continuation, biliary atresia, bowel obstruction and polysplenia. Fetal MR was a useful additional tool in the assessment of fetal abdominal anatomy in both cases. CONCLUSIONS: On the basis of these reports, the literature is reviewed and a prenatal management scheme is proposed.

Adult↗
PubMed2006

Prevalence and management of late fetal complications following successful selective laser coagulation of chorionic plate anastomoses in twin-to-twin transfusion syndrome.

OBJECTIVE: This study was undertaken to report on the prevalence and management of late complications in twin-to-twin transfusion syndrome (TTTS) treated by laser therapy when both twins are alive 1 week after surgery. STUDY DESIGN: A total of 151 consecutive TTTS cases were treated by selective fetoscopic laser therapy. Cases in which both twins were alive 1 week after surgery were followed up with ultrasound and Doppler examination, including middle-cerebral artery peak systolic velocity measurement (MCA-PSV). RESULTS: In the 151 cases treated with laser, both twins were still alive 7 days after the procedure in 101 cases. Intrauterine death of 1 and both twins occurred in 7 and 1 cases, respectively. Recurrence of TTTS with the polyhydramnios-oligohydramnios sequence occurred in 14 (14%) cases. In another 13 (13%) cases, amniotic fluid remained normal in both sacs, but MCA-PSV increased above 1.5 MoM in 1 twin and decreased concomitantly below 0.8 MoM in the co-twin. This was related to anemia and polycythemia, respectively, and resulted from unidirectional feto-fetal blood transfusion, mainly from former recipients into former donors. Late complications were managed accordingly by repeat laser, amnioreduction, cord coagulation, intrauterine blood transfusion, or elective delivery. CONCLUSION: MCA-PSV Doppler measurements are useful in the follow-up of double survivors to detect and manage late complications after selective laser therapy.

Anemia↗
PubMed2006

Safety of simple cystectomy in patients with unilateral mucinous borderline tumors.

OBJECTIVE: To report on ovarian carcinoma development after cystectomy for a borderline mucinous ovarian tumor. DESIGN: Case report. SETTING: A French comprehensive cancer center. PATIENT(S): One patient who developed recurrence in the form of an invasive ovarian carcinoma after simple cystectomy for a borderline mucinous ovarian tumor. INTERVENTION(S): Simple cystectomy. MAIN OUTCOME MEASURE(S): Clinical outcome. RESULT(S): A 22-year-old nulliparous patient underwent laparoscopic cystectomy. Histological examination revealed a borderline mucinous ovarian tumor. No additional treatment was prescribed. Two years later, the patient relapsed with a malignant mucinous ovarian carcinoma. She underwent surgical resection and staging, including hysterectomy, bilateral adnexectomy, omentectomy, and pelvic and para-aortic lymphadenectomy, and platinum-based chemotherapy. CONCLUSION(S): Recurrence in the form of invasive ovarian carcinoma may occur in the same ovary after cystectomy in cases of borderline mucinous ovarian tumor. An approach combining systematic unilateral salpingo-oophorectomy and strict monitoring is preferable to simple cystectomy. Such treatment enables preservation of reproductive potential and reduces the risk of developing invasive carcinoma.

Adenocarcinoma, Mucinous↗
PubMed2005

Placental perfusion MR imaging with contrast agents in a mouse model.

PURPOSE: To quantitatively analyze placental perfusion by using magnetic resonance (MR) imaging with contrast agents in a mouse model. MATERIALS AND METHODS: Study was conducted according to French law and in full compliance with National Institutes of Health recommendations for animal care. Thirty-six pregnant Balb/c mice at 16 days of gestation were injected intravenously with either a conventional or macromolecular gadolinium chelate, and 1.5-T single-section T1-weighted two-dimensional fast spoiled gradient-echo sequential MR imaging was then performed for 14 minutes. Images were analyzed qualitatively, and parametric map analysis was performed in the resultant 25 mice included in the study. Signal intensity was measured in maternal left ventricle (input function), placenta, and fetus on all images. After converting signal intensity into contrast agent tissue concentrations, a three-compartment model was developed with compartmental and numeric modeling software. Placental perfusion was calculated for conventional (n = 12) and macromolecular (n = 13) gadolinium chelates. Finally, placental and fetal gadolinium concentrations were assayed by means of atomic emission spectrophotometry (n = 15). Perfusion values and placental and fetal gadolinium concentrations for conventional and macromolecular chelates were compared by using an unpaired t test. RESULTS: Based on a constant transfer parameter, estimated placental perfusion did not differ between procedures with conventional and macromolecular gadolinium chelates (0.99 mL/min/g +/- 0.5 [standard deviation] and 1.28 mL/min/g +/- 0.6, respectively, P = .22). Likewise, mean placental gadolinium concentrations did not differ after injection of conventional and macromolecular chelates. In contrast, mean fetal gadolinium concentration was 9.83 micromol/L after conventional chelate injection and below detection limit after macromolecular chelate injection. CONCLUSION: Placental perfusion can be calculated by using dynamic contrast-enhanced MR imaging, as shown in this mouse model.

Animals↗
PubMed2005

Changes in progesterone-induced-blocking-factor expression rates following mifepristone administration in termination of pregnancy at 5 to 8 weeks.

OBJECTIVE: To study changes in the expression rate of PIBF by peripheral lymphocytes in healthy pregnant women after administration of mifepristone for non-surgical termination of pregnancy at 5-8 wks of gestation. METHODS: Patients requesting early social termination of pregnancy, in a 3-month period, were included. A first venous blood sample was taken before oral administration of 600 mg of mifepristone (day 0). A second venous blood sample was taken 2 days later. PIBF on lymphocytes was determined by immunocytochemistry using a PIBF-specific polyclonal antibody. RESULTS: Termination of pregnancy was successful and complete in all cases. In 17 out of 21 patients, the percentage of PIBF positive lymphocytes decreased after anti-progesterone administration. The percentage of PIBF-expressing lymphocytes significantly decreased from 52.8%+/-21.6% (day 0) to 39.8%+/-18.2% by day 2 (p=0.001). CONCLUSIONS: These data suggest a strong relationship between early termination of pregnancy induced with mifepristone and disturbances of progesterone-mediated immunosuppression.

Abortifacient Agents, Steroidal↗
PubMed2005

Analysis of fetal growth after laser therapy in twin-to-twin transfusion syndrome.

OBJECTIVE: The purpose of this study was to evaluate fetal growth patterns after laser therapy in twin-to-twin transfusion syndrome (TTTS). METHODS: All cases with delivery after 24 weeks from pregnancies complicated by TTTS treated by laser therapy between January 1999 and September 2004 were included. Fetal biometric parameters and estimated fetal weight were measured by sonography at least twice before laser therapy and twice after laser therapy. The interval between sonographic measurements was at least 2 weeks. The study population was divided into group I, which consisted of pregnancies with 2 liveborn neonates, and group II, which consisted of pregnancies resulting in only 1 liveborn neonate. The z scores for biometric measurements were calculated in all cases accordingly and compared for each twin across gestational age by analysis of variance and between groups by a t test. In group I, the intertwin discordance was also assessed, and analysis of variance was used to compare mean values across gestational age. RESULTS: Ninety-eight cases with 51 single and 47 double liveborn neonates were included. Across time, z scores of the recipients significantly decreased, whereas there was no change in z scores of the donors. The z scores were not statistically different between groups. There was a significant decrease in fetal discordance after laser therapy in group I. CONCLUSIONS: The fetal growth pattern in TTTS can change after laser treatment. There is a slowdown in the recipient growth and maintained growth in the donor twin. Both mechanisms lead to a decrease in intertwin discordance.

Analysis of Variance↗
PubMed2004

Fetal home monitoring for the prenatal management of gastroschisis.

BACKGROUND: Fetal distress is a frequent complication of gastroschisis, and could be screened for by home monitoring, as many pregnant women expecting an affected child live far away from a specialized perinatal center. This study was undertaken to audit a policy of fetal home monitoring (FHM) to achieve early detection of fetal heart rate (FHR) abnormalities in gastroschisis. METHODS: Daily FHM was started at a median age of 30 weeks in 31 pregnant women referred following prenatal diagnosis of isolated gastroschisis. Monitoring was considered abnormal in cases with decelerations, tachycardia, bradycardia, decreased baseline variability or absence of accelerations. When an ominous FHR was detected and confirmed by in-hospital monitoring, an emergency cesarean section (C-section) was indicated. Otherwise, an elective C-section was planned. RESULTS: In 20 cases FHM remained normal. There were 16 elective C-sections, two emergency C-sections for FHR abnormalities detected by in-hospital monitoring, and two spontaneous premature vaginal deliveries. In 11 cases, an abnormal FHM was detected. There was one intrauterine death with acute ischemic necrosis of the large bowel. The other abnormalities consisted of decreased baseline variability with tachycardia (n = 7) or without tachycardia (n = 3) and were confirmed by in-hospital follow-up in nine cases, leading to emergency C-section. CONCLUSION: The high rate of abnormal FHR patterns picked up by FHM in gastroschisis led to a rate of emergency C-sections of 9/31. However, this strategy failed to prevent one intrauterine death due to acute bowel necrosis.

Adolescent↗
PubMed2003

Severe preeclampsia is associated with high inhibin A levels and normal leptin levels at 7 to 13 weeks into pregnancy.

OBJECTIVE: The purpose of this study was to determine whether maternal serum inhibin A and leptin concentrations changed in the first trimester of pregnancy in patients in whom severe preeclampsia subsequently developed. STUDY DESIGN: Blood samples were collected prospectively from patients during the first trimester of prenatal care. Patients in whom severe preeclampsia with no evidence of glucose intolerance or gestational diabetes mellitus subsequently developed were identified (study group, 30 patients) and matched with control subjects in a 1:2 ratio (control group, 60 patients). Inhibin A and leptin concentrations were determined in these first-trimester serum samples for both the study and control groups. RESULTS: Leptin levels were correlated highly with body mass index in both groups but were not correlated with the subsequent onset of preeclampsia. Serum inhibin A concentrations were significantly higher in women in whom preeclampsia subsequently developed than in women in whom it did not. With a specific cutoff value, the estimated odds for severe preeclampsia were almost five times higher in women with high inhibin A concentrations than in women with normal levels (odds ratio, 4.93; 95% CI, 1.83, 13.28). CONCLUSION: High serum inhibin A levels in the first trimester of pregnancy could be used as an early risk marker for preeclampsia.

Adult↗
PubMed2002

Omphalocele: beyond the size issue.

A small omphalocele was diagnosed and followed up prenatally. Ultrasonography examinations and clinical examination at birth were all consistent with an isolated, small omphalocele. Immediate surgical exploration at birth found an associated type I intestinal atresia. This rare association and the need for immediate postnatal management of omphalocele are discussed, and the literature is reviewed.

Adult↗