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E H Whitby

Publications and source records attributed to E H Whitby.

14 recordsLinked to original sources
PubMed2007

The value of in-utero magnetic resonance imaging in ultrasound diagnosed foetal isolated cerebral ventriculomegaly.

AIM: To assess whether magnetic resonance imaging (MRI) is a useful adjunct to ultrasound (US) when imaging cases of foetal isolated cerebral ventriculomegaly. To assess whether, in such cases, ventricular morphology is a useful indicator for the underlying pathology, as has recently been suggested. MATERIALS AND METHODS: A retrospective analysis was undertaken of 30 cases of isolated ventriculomegaly diagnosed using US and referred for in utero MRI. The gestational age of each case was noted and the MRI report. Both ventricles were measured and each case was categorized according to severity and morphology. The MRI report was compared to the final diagnosis. RESULTS: Of the 30 cases evaluated 18 had mild ventriculomegaly (<15 mm; gestational age range 20-31 weeks, mean 22.8, median 22) and 12 had severe ventriculomegaly (>15 mm; gestational age range 21-37 weeks, mean 28, median 28.5). Additional abnormalities were found in 50% of cases overall (44% mild, 58% severe) using MRI. CONCLUSIONS: Using MRI additional abnormalities were identified in 50% of the foetuses. The morphology of the cases did not suggest underlying pathology in this group. In utero MRI is a useful adjunct to US in cases of foetal cerebral ventriculomegaly referred after initial diagnosis using US.

Abnormalities, Multiple↗
PubMed2006

Post-mortem fetal MRI: what do we learn from it?

Post-mortem magnetic resonance (MR) imaging is of increasing interest not only as an alternative to autopsy but as a research tool to aid the interpretation and diagnosis of in utero MR images. The information from the post-mortem MR has allowed the development of imaging sequences applicable to in utero imaging and neonatal imaging. It has established brain development during gestation and has provided data on this to which in utero MR can be compared. The detail available from the post-mortem images is such that brain development can be studied in a non-invasive manner, a permanent record on the normal and abnormal areas is available and a greater understanding of developmental abnormalities is possible.

Autopsy↗
PubMed2006

Post-mortem MRI of the foetal spine and spinal cord.

AIMS: To compare the findings of post-mortem magnetic resonance imaging (MRI) of the foetal spine with autopsy with a view to using post-mortem MRI as an alternative or adjunct to autopsy, particularly in foetal and neonatal cases. MATERIALS AND METHODS: The brains and spines of 41 foetuses, with a gestational age range of 14-41 weeks, underwent post-mortem MRI before autopsy. Post-mortem MRI of the brain consisted of T2-weighted sequences in three orthogonal planes and MRI of the spine consisted of T2-weighted sequence in the sagittal and axial planes in all cases and coronal planes in selected cases. RESULTS: Thirty of 41 (78%) foetal spines were found to be normal at autopsy and on post-mortem MRI. Eleven of 41 (22%) foetal spines were abnormal: eight foetuses had myelomeningocoeles and Chiari 2 deformities, one foetus had limited dorsal myeloschisis, one foetus had caudal regression syndrome, and one had diastematomyelia. The post-mortem MRI findings concurred with the autopsy findings in 10/11 of the abnormal cases, the disagreement being the case of diastematomyelia that was shown on post-mortem MRI but was not diagnosed at autopsy. CONCLUSIONS: In this series, post-mortem MRI findings agreed with the autopsy findings in 40/41(98%) cases and in one case the post-mortem MRI demonstrated an abnormality not demonstrated at autopsy.

Autopsy↗
PubMed2006

Normal fetal lumbar spine on postmortem MR imaging.

BACKGROUND AND PURPOSE: There is an increasing interest in use of postmortem MR imaging as an adjunct or alternative to autopsy. Before evaluating spinal pathology on postmortem MR imaging, it is important to have knowledge of the normal appearance of the fetal spine at different gestational ages. The aim of this study is to describe the MR imaging appearances of normal development of the fetal spine at different gestational ages. METHODS: Postmortem MR imaging was performed on 30 fetuses ranging from 14 to 41 gestational weeks. There was no structural abnormality of the spine in these fetuses on MR imaging or at autopsy. Fast spin-echo T2-weighted MR imaging of the lumbar spine was performed in the coronal plane in all cases and supplemented by sagittal and/or axial imaging. The following parameters were measured: height of the L1/2 disk and L2 vertebral body and area of ossification center in L2 vertebral body as well as area of vertebral body. The signal intensity of the disk space and the vertebral level of conus termination were also assessed. RESULTS: The height and area of the vertebral body increased linearly with gestational age (P <.01). The increase in disk space was proportionally greater than the increase in vertebral body height as gestational age increased (P <.01). The disk space appeared as a linear low-signal-intensity area in fetuses < or = 21 weeks gestation but increasingly developed high signal intensity in the disk after 21 weeks. The size of the ossification center increased with gestational age (P <.01), and the ratio of ossification center to the overall size of the vertebral body also increased with gestational age (P <.01). In fetuses less than 35 weeks of age, the conus lay between L2 and L5 level, whereas in fetuses more than 35 weeks of age, the conus lay between L1/2 and L2/3 level. CONCLUSION: Understanding the normal growth and signal-intensity characteristics of the fetal spine on postmortem MR imaging is essential before studying abnormal fetal spine.

Autopsy↗
PubMed2004

Frequency and natural history of subdural haemorrhages in babies and relation to obstetric factors.

BACKGROUND: Subdural haematomas are thought to be uncommon in babies born at term. This view is mainly based on findings in symptomatic neonates and babies in whom subdural haemorrhages are detected fortuitously. We aimed to establish the frequency of subdural haemorrhages in asymptomatic term neonates; to study the natural history of such subdural haematomas; and to ascertain which obstetric factors, if any, are associated with presence of subdural haematoma. METHODS: We did a prospective study in babies who were born in the Jessop wing of the Central Sheffield University Hospitals between March, 2001, and November, 2002. We scanned neonates with a 0.2 T magnetic resonance machine. FINDINGS: 111 babies underwent MRI in this study. 49 were born by normal vertex delivery without instrumentation, 25 by caesarean section, four with forceps, 13 ventouse, 18 failed ventouse leading to forceps, one failed ventouse leading to caesarean section, and one failed forceps leading to caesarean section. Nine babies had subdural haemorrhages: three were normal vaginal deliveries (risk 6.1%), five were delivered by forceps after an attempted ventouse delivery (27.8%), and one had a traumatic ventouse delivery (7.7%). All babies with subdural haemorrhage were assessed clinically but no intervention was needed. All were rescanned at 4 weeks and haematomas had completely resolved. INTERPRETATION: Presence of unilateral and bilateral subdural haemorrhage is not necessarily indicative of excessive birth trauma.

Apgar Score↗
PubMed2004

Corroboration of in utero MRI using post-mortem MRI and autopsy in foetuses with CNS abnormalities.

AIMS: To corroborate the findings of in utero magnetic resonance imaging (MRI) with autopsy and post-mortem MRI in cases of known or suspected central nervous system (CNS) abnormalities on ultrasound and to compare the diagnostic accuracy of ante-natal ultrasound and in utero MRI. METHODS: Twelve pregnant women, whose foetuses had suspected central nervous system abnormalities underwent in utero MRI. The foetuses were imaged using MRi before autopsy. The data were used to evaluate the diagnostic accuracy of in utero MRI when compared with a reference standard of autopsy and post-mortem MRI in 10 cases and post-mortem MRI alone in two cases. RESULTS: The diagnostic accuracy of antenatal ultrasound and in utero MRI in correctly characterizing brain and spine abnormalities were 42 and 100%, respectively. CONCLUSION: In utero MRI provides a useful adjuvant to antenatal ultrasound when assessing CNS abnormalities by providing more accurate anatomical information. Post-mortem MRI assists the diagnosis of macroscopic structural abnormalities.

Adult↗
PubMed2004

Comparison of ultrasound and magnetic resonance imaging in 100 singleton pregnancies with suspected brain abnormalities.

OBJECTIVE: To compare the diagnostic accuracy of the current reference standard-ultrasound with in utero magnetic resonance imaging, in a selected group of patients. DESIGN: Prospective study. SETTING: Five fetal maternal tertiary referral centres and an academic radiology unit. SAMPLE: One hundred cases of fetuses with central nervous system abnormalities where there has been diagnostic difficulties on ultrasound. In 48 cases the women were less than 24 weeks of gestation and in 52 cases later in pregnancy. METHODS: All women were imaged on a 1.5 T clinical system using a single shot fast spin echo technique. The results of antenatal ultrasound and in utero magnetic resonance were compared. MAIN OUTCOME MEASURES: The definitive diagnosis was made either at autopsy or by postmortem magnetic resonance imaging, in cases that went to termination of pregnancy, or a combination of postnatal imaging and clinical follow up in the others. RESULTS: In 52 of cases, ultrasound and magnetic resonance gave identical results and in a further 12, magnetic resonance provided extra information that was judged not to have had direct effects on management. In 35 of cases, magnetic resonance either changed the diagnosis (29) or gave extra information that could have altered management (6). In 11 of the 30 cases where magnetic resonance changed the diagnosis, the brain was described as normal on magnetic resonance. CONCLUSIONS: In utero magnetic resonance imaging is a powerful tool in investigating fetal brain abnormalities. Our results suggest that in selected cases of brain abnormalities, detected by ultrasound, antenatal magnetic resonance may provide additional, clinically useful information that may alter management.

Brain↗
PubMed2003

Low field strength magnetic resonance imaging of the neonatal brain.

BACKGROUND: Magnetic resonance (MR) imaging of the neonate has been restricted by the need to transport the sick baby to the large magnetic resonance scanners and often the need for sedation or anaesthesia in order to obtain good quality images. Ultrasound is the reference standard for neonatal imaging. OBJECTIVE: To establish a dedicated neonatal MR system and compare the clinical usefulness of MR imaging with ultrasound imaging. DESIGN: Prospective double blind trial. SETTING: Neonatal intensive care unit, Sheffield. MAIN OUTCOME MEASURES: Imaging reports. PATIENTS: 134 premature and term babies. RESULTS: In 56% of infants with pathology suspected on clinical grounds, MR provided additional useful clinical information over and above that obtained with ultrasound. CONCLUSION: Infants can be safely imaged by dedicated low field magnetic resonance on the neonatal intensive care unit without the need for sedation at a cost equivalent to ultrasound.

Brain↗
PubMed2003

MR imaging of the fetal brain and spine: a maturing technology.

INTRODUCTION: We describe the background and refinements to a 3-year research study designed to evaluate the role of magnetic resonance (MR) imaging in detecting and defining abnormalities of the fetal central nervous system in utero. METHODS: We describe our experience of using ultra-fast MR imaging methods (specifically single-shot fast spin echo) in 250 fetuses at various gestational ages. All fetuses had known or suspected brain or spine abnormalities based on antenatal ultrasound imaging. We describe the ethical issues raised by this type of work and the differences in diagnostic accuracy between ultrasound and MR imaging. RESULTS: We show that MR imaging can be performed in a clinical environment with a high degree of success: only 2 women out of 250 could not be examined (1 was claustrophobic and the other was too large for our scanner). In the 100 cases of singleton pregnancies, where detailed follow-up is available, there is a > 40% improvement in diagnostic accuracy when MR imaging is included in the fetal assessment compared to ultrasound alone. CONCLUSION: We conclude that in utero MR imaging is a powerful tool in the assessment of fetal brain and spine abnormalities, and suggest that further work be undertaken to provide a widely available clinical service.

Brain↗
PubMed1995

Fractures of the lateral process of the talus--the value of lateral tomography.

We present three cases of fractures of the lateral process of the talus, where routine anteroposterior and lateral radiographs showed an abnormality but were insufficient to assess the degree of bony injury, which is important for clinical management. Lateral tomography provided good diagnostic and anatomical detail. The diagnosis and treatment of this unusual and often missed fracture is discussed.

Adult↗
PubMed1990

Allograft rejection in athymic nude rats by transferred T cell subsets. II. The response of naive CD4+ and CD8+ thoracic duct lymphocytes to an isolated MHC class I disparity.

Athymic PVG-rnu/rnu (RT1c) rats were grafted with skin bearing isolated MHC disparities 7-14 days in advance of cell transfer. The ability of naive CD4+ or CD8+ thoracic duct lymphocytes to induce rejection was assessed by adoptive transfer of one or both T cell subsets into nude recipients bearing congenic PVG.r1 (MHC class I-only disparity, Aa) or PVG.r19 (class I and II-only disparity, Aa B/Da) skin grafts. Recipients of purified CD4+ TDL always rejected r19 allografts, whereas CD8+ TDL were ineffective against this class I + II difference. Neither the injection of CD4+ TDL nor CD8+ TDL alone resulted in destruction of r1 skin grafts. However, rejection of r1 tissue was observed in 63% of cases (19/30) when both CD4+ and CD8+ TDL were present in the nude recipients. Rejection of r1 skin was also induced in some recipients when CD8+ TDL were transferred 8 weeks in advance of CD4+ TDL. In contrast, sequential transfer in the reverse order apparently induced tolerance in the CD4+ population--i.e., surviving r1 skin grafts on 8 week CD4+ T cell-reconstituted nude recipients were not rejected following the subsequent transfer of CD8+ TDL. We conclude that CD4+ T cells were required for rejection of both class I and class II differences. In the presence of a class II difference, CD4+ T cells function autonomously to initiate both the inducer and effector stages of rejection. When the disparity is confined to class I, CD8+ T cells are required (probably at the effector stage) but are dependent on CD4+ T cells for help. There was no evidence of CD4+ effector T cells that could recognize class I directly within the graft.

Animals↗
PubMed1990

Allograft rejection in athymic nude rats by transferred T-cell subsets. I. The response of naive CD4+ and CD8+ thoracic duct lymphocytes to complete allogeneic incompatibilities.

PVG.rnu/rnu nude rats were pre-grafted with two allogeneic skin grafts, AO(RTlu) and BN(RTln), 6-14 days in advance of cell transfer. Cellular requirements for rejection were established by transferring graded numbers of B cell-depleted (Ig-) thoracic duct lymphocytes (TDL) or purified W3/25+ (CD4+) or OX8+ (CD8+) TDL subsets. Allografts were rejected by 10(5) to 5 x 10(6) Ig- TDL in a dose-dependent fashion. A similar dose-response relationship was found by transferring 5 x 10(5) to 5 x 10(6) Ig- OX8- TDL (purified by depletion of B cells and OX8+ cells). Larger numbers of Ig- OX8- TDL (10-30 x 10(6)) did not significantly accelerate rejection. W3/25+ TDL alone (10(5)), highly purified by fluorescence-activated cell sorting (FACS), were sufficient to induce allograft rejection in this athymic nude rat model. In contrast, 10 times more FACS purified OX8+ TDL (10(6)) were unable to initiate skin graft rejection despite the complete class I and class II MHC incompatibilities. Furthermore, the addition of 10(6) OX8+ cells did not accelerate or retard the rejection induced by 10(5) W3/25+ cells alone. Pre-grafted nude recipients, irradiated (500 R) 2 hr before W3/25+ TDL injection, in order to eliminate putative nude T cells, rejected allografts on the same day as unirradiated controls. We conclude that when confronted with complete MHC disparities, CD4+ T cells are necessary and sufficient to induce skin allograft rejection whereas CD8+ T cells do not appear to contribute.

Animals↗
PubMedDate not supplied

Post-mortem MRI as an adjunct to fetal or neonatal autopsy.

CONTEXT: Understanding what was wrong with a dead fetus or why a newborn child died can help the parents to grieve, while any findings can be used to inform the parents if there is a risk to future pregnancies and the level of risk. This information is mainly obtained from autopsies, but the number of parents agreeing to autopsy has dropped, which has prompted the search for adjuncts to autopsy. STARTING POINT: The UK's Chief Medical Officer outlined the rationale for exploring alternatives to autopsy in 2000 and 2001. After wide consultation, MRI was deemed to offer the most realistic chance of making a contribution. Results so far are promising, but of insufficient depth and quality to make firm recommendations about providing a service in the future. In 2004, the UK Department of Health therefore tendered for this research to be done in fetal and neonatal (and adult) cases, and this work is due to start in 2005. WHERE NEXT? High-quality anatomical information about the brain and spine of fetuses and neonates can be easily obtained with standard MRI scanners. Most developmental and acquired abnormalities can be seen on post-mortem MRI. More work needs to be done on organs not in the central nervous system, and heart malformations, in particular, might present diagnostic problems. A possible outcome could be whole-body MRI plus targeted biopsies of abnormalities taken under image guidance as an adjunct to formal autopsy.

Autopsy↗