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K H Nicolaides - One of the best experts on this subject based on the ideXlab platform.
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mean arterial pressure at 11 0 to 13 6 weeks in the prediction of preeclampsia
Hypertension, 2008Co-Authors: Leona Poon, Nikos A Kametas, Ivilina Pandeva, Catalina Valencia, K H NicolaidesAbstract:This study aimed to determine the performance of screening for preeclampsia (PE) by maternal medical history and mean arterial pressure (MAP) at 11 +0 to 13 +6 weeks. In 5590 women with singleton pregnancies attending for routine care at 11 +0 to 13 +6 week’s gestation we recorded maternal variables and measured the MAP. We excluded 397 because they had missing outcome data or the pregnancies resulted in miscarriage or termination. In 104 patients there was subsequent development of PE, 97 developed gestational hypertension, 574 delivered small-for-gestational-age newborns, and 4418 were unaffected by PE, gestational hypertension, or small for gestational age. A multivariate Gaussian model was fitted to the distribution of log multiple of the median MAP in the PE and unaffected groups. Likelihood ratios for log multiple of the median MAP were computed and used together with maternal variables to produce patient-specific risks for each case. Detection rates and false-positive rates were calculated by taking the proportions with risks above a given risk threshold. In the unaffected group, log MAP was influenced by maternal age, Ethnic Origin, smoking, family and personal history of PE, and fetal crown-rump length. In the prediction of PE, significant contributions were provided by log multiple of the median MAP, Ethnic Origin, body mass index, and personal history of PE. The detection rate of PE by log multiple of the median MAP and maternal variables was 62.5% for a false-positive rate of 10%. Maternal variables, together with MAP, at 11 +0 to 13 +6 weeks identify a group at high risk for development of PE.
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uterine artery doppler at 11 0 to 13 6 weeks in the prediction of pre eclampsia
Ultrasound in Obstetrics & Gynecology, 2007Co-Authors: Walter Plasencia, Nerea Maiz, S Bonino, C Kaihura, K H NicolaidesAbstract:Objective To determine the performance of screening for pre-eclampsia (PET) by maternal characteristics and uterine artery pulsatility index (PI) at 11 + 0 to 13 + 6 weeks' gestation. Methods In women with singleton pregnancies attending for routine care at 11 + 0 to 13 + 6 weeks' gestation we recorded maternal variables and measured the uterine artery PI. We identified 107 cases that subsequently developed PET and 5041 that were unaffected by PET, gestational hypertension or delivery of newborns with birth weight below the 10th centile. A multivariate Gaussian model was fitted to the distribution of log multiples of the median (MoM) PI in the PET and unaffected groups. Likelihood ratios for log MoM PI were computed and used together with maternal variables to produce patient-specific risks for each case. Predicted detection rates (DR) and false-positive rates (FPR) were calculated by taking the proportions with risks above a given risk threshold. Results In the unaffected group log MoM PI was influenced by maternal Ethnic Origin, body mass index, previous history of PET and fetal crown–rump length. In the prediction of PET significant contributions were provided by log MoM PI, Ethnic Origin, body mass index and previous and family history of PET. For an FPR of 10% the DRs of all PET and PET leading to delivery before 34 weeks' gestation by log MoM PI and maternal variables were 61.7% and 81.8%, respectively. Conclusion Maternal variables together with uterine artery PI at 11 + 0 to 13 + 6 weeks' gestation provide sensitive prediction of the development of PET, especially of severe early-onset PET. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.
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likelihood ratio for trisomy 21 in fetuses with absent nasal bone at the 11 14 week scan
Ultrasound in Obstetrics & Gynecology, 2004Co-Authors: S Cicero, G Rembouskos, H Vandecruys, M Hogg, K H NicolaidesAbstract:Objective To update the likelihood ratio for trisomy 21 in fetuses with absent nasal bone at the 11–14-week scan. Methods Ultrasound examination of the fetal profile was carried out and the presence or absence of the nasal bone was noted immediately before karyotyping in 5918 fetuses at 11 to 13+6 weeks. Logistic regression analysis was used to examine the effect of maternal Ethnic Origin and fetal crown–rump length (CRL) and nuchal translucency (NT) on the incidence of absent nasal bone in the chromosomally normal and trisomy 21 fetuses. Results The fetal profile was successfully examined in 5851 (98.9%) cases. In 5223/5851 cases the fetal karyotype was normal and in 628 cases it was abnormal. In the chromosomally normal group the incidence of absent nasal bone was related first to the Ethnic Origin of the mother, being 2.2% for Caucasians, 9.0% for Afro-Caribbeans and 5.0% for Asians; second to fetal CRL, being 4.7% for CRL of 45–54 mm, 3.4% for CRL of 55–64 mm, 1.4% for CRL of 65–74 mm and 1% for CRL of 75–84 mm; and third to NT, being 1.6% for NT ≤ 95th centile, 2.7% for NT > 95th centile–3.4 mm, 5.4% for NT 3.5–4.4 mm, 6% for NT 4.5–5.4 mm and 15% for NT ≥ 5.5 mm. In the chromosomally abnormal group there was absent nasal bone in 229/333 (68.8%) cases with trisomy 21 and in 95/295 (32.2%) cases with other chromosomal defects. Logistic regression analysis demonstrated that in the chromosomally normal fetuses significant independent prediction of the likelihood of absent nasal bone was provided by CRL, NT and Afro-Caribbean Ethnic group, and in the trisomy 21 fetuses by CRL and NT. The likelihood ratio for trisomy 21 for absent nasal bone was derived by dividing the likelihood in trisomy 21 by that in normal fetuses. Conclusion At the 11–14-week scan the incidence of absent nasal bone is related to the presence or absence of chromosomal defects, CRL, NT and Ethnic Origin. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd.
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absent nasal bone at 11 14 weeks of gestation and chromosomal defects
Ultrasound in Obstetrics & Gynecology, 2003Co-Authors: S Cicero, D Longo, G Rembouskos, C Sacchini, K H NicolaidesAbstract:Objective To examine the association between absence of the nasal bone at the 11–14-week ultrasound scan and chromosomal defects. Methods Ultrasound examination was carried out in 3829 fetuses at 11–14 weeks' gestation immediately before fetal karyotyping. At the scan the fetal crown–rump length (CRL) and nuchal translucency (NT) thickness were measured and the fetal profile was examined for the presence or absence of the nasal bone. Maternal characteristics including Ethnic Origin were also recorded. Results The fetal profile was successfully examined in 3788 (98.9%) cases. In 3358/3788 cases the fetal karyotype was normal and in 430 it was abnormal. In the chromosomally normal group the incidence of absent nasal bone was related firstly to the Ethnic Origin of the mother (2.8% for Caucasians, 10.4% for Afro-Caribbeans and 6.8% for Asians), secondly to fetal CRL (4.6% for CRL of 45–54 mm, 3.9% for CRL of 55–64 mm, 1.5% for CRL of 65–74 mm and 1.0% for CRL of 75–84 mm) and thirdly, to NT thickness, (1.8% for NT < 2.5 mm, 3.4% for NT 2.5–3.4 mm, 5.0% for NT 3.5–4.4 mm and 11.8% for NT ≥ 4.5 mm. In the chromosomally abnormal group the nasal bone was absent in 161/242 (66.9%) with trisomy 21, in 48/84 (57.1%) with trisomy 18, in 7/22 (31.8%) with trisomy 13, in 3/34 (8.8%) with Turner syndrome and in 4/48 (8.3%) with other defects. Conclusion At the 11–14-week scan the incidence of absent nasal bone is related to the presence or absence of chromosomal defects, CRL, NT thickness and Ethnic Origin. Copyright © 2003 ISUOG. Published by John Wiley & Sons, Ltd.
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the influence of Ethnic Origin on first trimester biochemical markers of chromosomal abnormalities
Prenatal Diagnosis, 2000Co-Authors: Kevin Spencer, Charas Y T Ong, A W Liao, K H NicolaidesAbstract:In a first trimester study of 5422 Caucasian women, 752 Afro-Caribbean women and 170 Asian women we have shown that the median maternal serum marker MoMs for free b-hCG and PAPP-A were 19% and 48% higher in Afro-Caribbean women and 19% higher and 35% higher in Asian women, compared to Caucasian women. Correcting for maternal weight made very little difference to the effect in Afro-Caribbeans (21% and 57% higher after weight correction) but reduced the effect in Asians (4% and 17% higher after weight correction ). It is estimated that correcting for maternal weight and Ethnicity overall would increase the detection rate by a modest 1.4%. However, the effect on an individual’s risk could result in as much as a two-fold increase in the patient specific risk for trisomy 21. The impact of Ethnic Origin seems to be greater than that observed with second trimester biochemical markers and larger studies are required in order to develop robust algorithms for correcting for Ethnic Origin in the first trimester. Copyright # 2000 John Wiley & Sons, Ltd.
Roger Williams - One of the best experts on this subject based on the ideXlab platform.
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Ethnic variations in patient and graft survival after liver transplantation identification of a new risk factor for chronic allograft rejection
Transplantation, 1993Co-Authors: John Devlin, J Ogrady, K C Tan, R Y Calne, Roger WilliamsAbstract:The Ethnic Origin of renal graft recipients is recognized as an important determinant of graft survival. In liver transplantation, the effect of racial Origin has been studied in black American recipients and has suggested a trend toward inferior graft survival in this group. In this study, we have analyzed outcome of transplantation in a large multiEthnic liver transplant program. Non-Caucasoid recipients had an inferior patient survival compared with Caucasoids and, in particular, European Caucasoids at 1, 3, and 5 years after transplantation (46.7% vs. 60.2% at 3 years, P = 0.05). Non-European recipients had an inferior graft survival compared with European recipients at 1, 2, and 3 years after transplantation (e.g., north Europeans 53.5%, south Europeans 48.5%, Middle Eastern 40%, and non-Caucasoids 27% at 3 years, P < 0.01). Different frequencies of chronic allograft rejection in the Ethnic groups contributed to the rates of graft survival, with the non-European recipients developing chronic rejection at over twice the rate of European recipients (12.6% vs. 5.9%, respectively, P = 0.002). The findings in this study support the evidence from renal transplant programs that the Ethnic Origin of recipients is an important determinant of outcome after transplantation, with increasing frequency of chronic rejection in recipients nonindigenous to the donor population contributing to the variations in patient and graft survival rates.
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Ethnic variations in patient and graft survival after liver transplantation identification of a new risk factor for chronic allograft rejection
Transplantation, 1993Co-Authors: John Devlin, J Ogrady, R Y Calne, Roger WilliamsAbstract:The Ethnic Origin of renal graft recipients is recognized as an important determinant of graft survival. In liver transplantation, the effect of racial Origin has been studied in black American recipients and has suggested a trend toward inferior graft survival in this group. In this study, we have analyzed outcome of transplantation in a large multiEthnic liver transplant program. NonCaucasoid recipients had an inferior patient survival compared with Caucasoids and, in particular, European Caucasoids at 1, 3, and 6 years after transplantation (46.7% vs. 60.2% at 3 years, P=0.05)
Miguel E. Cabanela - One of the best experts on this subject based on the ideXlab platform.
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transtrochanteric anterior rotational osteotomy for avascular necrosis of the femoral head long term results
Journal of Bone and Joint Surgery-british Volume, 1993Co-Authors: Michael T Dean, Miguel E. CabanelaAbstract:We reviewed 18 hips in 17 patients at a mean of five years after performing Sugioka's transtrochanteric anterior rotational osteotomy for avascular necrosis. The results were satisfactory in only three hips (17%). Twelve hips had been revised by hip replacement, revision was pending in one and two others were unsatisfactory. Hip replacement was not compromised by the previous Sugioka osteotomy. Fifteen hips (83%) had shown further collapse of the femoral head, and we conclude from this and from isotope scans that the osteotomy may have impaired the residual blood supply of the femoral head. It seems that Ethnic Origin may be a factor in the outcome of this procedure; we have abandoned its use.
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transtrochanteric anterior rotational osteotomy for avascular necrosis of the femoral head
1993Co-Authors: Michael T Dean, Miguel E. CabanelaAbstract:We reviewed 18 hips in 17 patients at a mean of five years after performing Sugioka’s transtrochanteric anterior rotational osteotomy for avascular necrosis. The results were satisfactory in only three hips (17%). Twelve hips had been revised by hip replacement, revision was pending in one and two others were unsatisfactory. Hip replacement was not compromised by the previous Sugioka osteotomy. Fifteen hips (83%) had shown further collapse of the femoral head, and we conclude from this and from isotope scans that the osteotomy may have impaired the residual blood supply of the femoral head. It seems that Ethnic Origin may be a factor in the outcome of this procedure; we have abandoned its use. J Bone JointSurg [Br] 1993 ; 75-B :�97-601.
John Devlin - One of the best experts on this subject based on the ideXlab platform.
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Ethnic variations in patient and graft survival after liver transplantation identification of a new risk factor for chronic allograft rejection
Transplantation, 1993Co-Authors: John Devlin, J Ogrady, K C Tan, R Y Calne, Roger WilliamsAbstract:The Ethnic Origin of renal graft recipients is recognized as an important determinant of graft survival. In liver transplantation, the effect of racial Origin has been studied in black American recipients and has suggested a trend toward inferior graft survival in this group. In this study, we have analyzed outcome of transplantation in a large multiEthnic liver transplant program. Non-Caucasoid recipients had an inferior patient survival compared with Caucasoids and, in particular, European Caucasoids at 1, 3, and 5 years after transplantation (46.7% vs. 60.2% at 3 years, P = 0.05). Non-European recipients had an inferior graft survival compared with European recipients at 1, 2, and 3 years after transplantation (e.g., north Europeans 53.5%, south Europeans 48.5%, Middle Eastern 40%, and non-Caucasoids 27% at 3 years, P < 0.01). Different frequencies of chronic allograft rejection in the Ethnic groups contributed to the rates of graft survival, with the non-European recipients developing chronic rejection at over twice the rate of European recipients (12.6% vs. 5.9%, respectively, P = 0.002). The findings in this study support the evidence from renal transplant programs that the Ethnic Origin of recipients is an important determinant of outcome after transplantation, with increasing frequency of chronic rejection in recipients nonindigenous to the donor population contributing to the variations in patient and graft survival rates.
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Ethnic variations in patient and graft survival after liver transplantation identification of a new risk factor for chronic allograft rejection
Transplantation, 1993Co-Authors: John Devlin, J Ogrady, R Y Calne, Roger WilliamsAbstract:The Ethnic Origin of renal graft recipients is recognized as an important determinant of graft survival. In liver transplantation, the effect of racial Origin has been studied in black American recipients and has suggested a trend toward inferior graft survival in this group. In this study, we have analyzed outcome of transplantation in a large multiEthnic liver transplant program. NonCaucasoid recipients had an inferior patient survival compared with Caucasoids and, in particular, European Caucasoids at 1, 3, and 6 years after transplantation (46.7% vs. 60.2% at 3 years, P=0.05)
S Cicero - One of the best experts on this subject based on the ideXlab platform.
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likelihood ratio for trisomy 21 in fetuses with absent nasal bone at the 11 14 week scan
Ultrasound in Obstetrics & Gynecology, 2004Co-Authors: S Cicero, G Rembouskos, H Vandecruys, M Hogg, K H NicolaidesAbstract:Objective To update the likelihood ratio for trisomy 21 in fetuses with absent nasal bone at the 11–14-week scan. Methods Ultrasound examination of the fetal profile was carried out and the presence or absence of the nasal bone was noted immediately before karyotyping in 5918 fetuses at 11 to 13+6 weeks. Logistic regression analysis was used to examine the effect of maternal Ethnic Origin and fetal crown–rump length (CRL) and nuchal translucency (NT) on the incidence of absent nasal bone in the chromosomally normal and trisomy 21 fetuses. Results The fetal profile was successfully examined in 5851 (98.9%) cases. In 5223/5851 cases the fetal karyotype was normal and in 628 cases it was abnormal. In the chromosomally normal group the incidence of absent nasal bone was related first to the Ethnic Origin of the mother, being 2.2% for Caucasians, 9.0% for Afro-Caribbeans and 5.0% for Asians; second to fetal CRL, being 4.7% for CRL of 45–54 mm, 3.4% for CRL of 55–64 mm, 1.4% for CRL of 65–74 mm and 1% for CRL of 75–84 mm; and third to NT, being 1.6% for NT ≤ 95th centile, 2.7% for NT > 95th centile–3.4 mm, 5.4% for NT 3.5–4.4 mm, 6% for NT 4.5–5.4 mm and 15% for NT ≥ 5.5 mm. In the chromosomally abnormal group there was absent nasal bone in 229/333 (68.8%) cases with trisomy 21 and in 95/295 (32.2%) cases with other chromosomal defects. Logistic regression analysis demonstrated that in the chromosomally normal fetuses significant independent prediction of the likelihood of absent nasal bone was provided by CRL, NT and Afro-Caribbean Ethnic group, and in the trisomy 21 fetuses by CRL and NT. The likelihood ratio for trisomy 21 for absent nasal bone was derived by dividing the likelihood in trisomy 21 by that in normal fetuses. Conclusion At the 11–14-week scan the incidence of absent nasal bone is related to the presence or absence of chromosomal defects, CRL, NT and Ethnic Origin. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd.
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absent nasal bone at 11 14 weeks of gestation and chromosomal defects
Ultrasound in Obstetrics & Gynecology, 2003Co-Authors: S Cicero, D Longo, G Rembouskos, C Sacchini, K H NicolaidesAbstract:Objective To examine the association between absence of the nasal bone at the 11–14-week ultrasound scan and chromosomal defects. Methods Ultrasound examination was carried out in 3829 fetuses at 11–14 weeks' gestation immediately before fetal karyotyping. At the scan the fetal crown–rump length (CRL) and nuchal translucency (NT) thickness were measured and the fetal profile was examined for the presence or absence of the nasal bone. Maternal characteristics including Ethnic Origin were also recorded. Results The fetal profile was successfully examined in 3788 (98.9%) cases. In 3358/3788 cases the fetal karyotype was normal and in 430 it was abnormal. In the chromosomally normal group the incidence of absent nasal bone was related firstly to the Ethnic Origin of the mother (2.8% for Caucasians, 10.4% for Afro-Caribbeans and 6.8% for Asians), secondly to fetal CRL (4.6% for CRL of 45–54 mm, 3.9% for CRL of 55–64 mm, 1.5% for CRL of 65–74 mm and 1.0% for CRL of 75–84 mm) and thirdly, to NT thickness, (1.8% for NT < 2.5 mm, 3.4% for NT 2.5–3.4 mm, 5.0% for NT 3.5–4.4 mm and 11.8% for NT ≥ 4.5 mm. In the chromosomally abnormal group the nasal bone was absent in 161/242 (66.9%) with trisomy 21, in 48/84 (57.1%) with trisomy 18, in 7/22 (31.8%) with trisomy 13, in 3/34 (8.8%) with Turner syndrome and in 4/48 (8.3%) with other defects. Conclusion At the 11–14-week scan the incidence of absent nasal bone is related to the presence or absence of chromosomal defects, CRL, NT thickness and Ethnic Origin. Copyright © 2003 ISUOG. Published by John Wiley & Sons, Ltd.