Stephen S. Ong
Nottingham City Hospital
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Stephen S. Ong.
Human Brain Mapping | 2004
Jonathan Fulford; Shantala H. Vadeyar; Sanani H. Dodampahala; Stephen S. Ong; Rachel J. Moore; Philip N. Baker; David James; Penny A. Gowland
Previous studies have demonstrated the practicality of using functional magnetic resonance imaging (fMRI) techniques to assess fetal brain activity. The purpose of this study was to compare the fetal hemodynamic response to that of the adult. Seventeen pregnant subjects, all of whom were at more than 36 weeks gestation were scanned while the fetus was exposed to a vibroacoustic stimulus. Thirteen adult subjects were scanned with an equivalent acoustic stimulus. Of the fetal subjects, two could not be analyzed due to technical problems, eight did not show significant activation, and seven showed significant activation. In all cases, activation was localized within the temporal region. Measures of fetal hemodynamic responses revealed an average time to peak (ttp) of 7.36 ± 0.94 sec and an average percentage change of 2.67 ± 0.93%. In contrast, activation was detected in 5 of 13 adults with an average ttp of 6.54 ± 0.54 sec and an average percentage change of 1.02 ± 0.40%. The measurement of changes in the fetal hemodynamic response may be important in assessing compromised pregnancies. Hum. Brain Mapping 22:118–123, 2004.
British Journal of Obstetrics and Gynaecology | 2003
Stephen S. Ong; Rachel J. Moore; Averil Y. Warren; Ian P. Crocker; Jon Fulford; Damian J. Tyler; Penny A. Gowland; Philip N. Baker
Objectives (1) To investigate a possible association between myometrial and placental artery vasoreactivity and perfusion at the basal and chorionic plates, respectively. (2) To confirm that myometrial arteries from women with pre‐eclampsia and intrauterine growth restriction exhibit an attenuated endothelium‐dependent vasodilatory response.
Hypertension in Pregnancy | 2002
Stephen S. Ong; Ian P. Crocker; Averil Y. Warren; Philip N. Baker
Objectives: We aimed to compare placental small artery function from women with pre-eclampsia and normal pregnancy. In particular, we wished to test the hypothesis that these arteries respond differently to an endothelium-dependent vasodilator, to the presence of nitric oxide, and to the presence of cyclic monophosphate nucleotides. Methods: A small vessel wire myograph was used to study placental arteries (200 to 550 μm). Contractile function was assessed with vasopressin. Relaxation was assessed with the endothelium-dependent vasodilator, bradykinin, and the endothelium-independent vasodilators sodium nitroprusside (a nitric oxide donor) and papaverine (a phosphodiesterase inhibitor). Results: The constrictor response to vasopressin did not differ between patient groups (p=0.79; repeated measures ANOVA). For both normal pregnancy and pre-eclampsia, the response of pre-constricted arteries to the endothelium-dependent vasodilator, bradykinin, was minimal. Vasorelaxation to sodium nitroprusside and papaverine was attenuated in pre-eclampsia compared to normal pregnancy (p=0.03 and p<0.001, respectively; repeated measures ANOVA). Conclusions: In pre-eclampsia, placental arteries exhibit an attenuated vasodilatory response to nitric oxide.
Placenta | 2003
Terry M. Mayhew; C. Ohadike; Philip N. Baker; Ian P. Crocker; Christopher A. Mitchell; Stephen S. Ong
Placenta | 2004
Terry M. Mayhew; J. Wijesekara; Philip N. Baker; Stephen S. Ong
American Journal of Obstetrics and Gynecology | 2005
Stephen S. Ong; Philip N. Baker; Terry M. Mayhew; William R. Dunn
NMR in Biomedicine | 2008
Rachel J. Moore; Stephen S. Ong; Damian J. Tyler; Rachel Duckett; Philip N. Baker; William R. Dunn; Ian R. Johnson; Penny A. Gowland
Placenta | 2004
Stephen S. Ong; Damian J. Tyler; Rachel J. Moore; Penny A. Gowland; Philip N. Baker; Ian R. Johnson; Terry M. Mayhew
American Journal of Obstetrics and Gynecology | 2002
Stephen S. Ong; Philip N. Baker; Terence M. Mayhew; William R. Dunn
American Journal of Obstetrics and Gynecology | 2016
Fionnuala Mone; Barbara McConnell; Andrew Thompson; Ricardo Segurado; Peter Hepper; Moira Stewart; James Dornan; Stephen S. Ong; Fionnuala McAuliffe; Michael D. Shields