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ABSTRACT: Objective. To assess the natural history of isolated syringomyelia in children. Methods. MRI reports from February 2007 to August 2011 mentioning syrinx were identified on Sheffield Children's PACS database. Scans with syringes having an AP diameter of > 1 mm and extending over at least two vertebral bodies were reviewed. Patients with an identifiable cause such as a Chiari malformation were then excluded. Results. Thirty-nine patients were included with a mean age at diagnosis of 10.6 years. The average syrinx AP diameter was 3.30 mm. The rostrocaudal length of the syringes varied between 2 and 19 vertebral bodies. Twenty-seven out of 39 syringes were thoracic in origin. There were 3 and 6 syringes involving the cervicothoracic and thoracolumbar regions, respectively, with 3 involving the cervical area only. Eleven out of 39 (Group I) patients were found "incidentally" during work-up for adolescent idiopathic scoliosis and these were considered as a separate group. These patients did not have any significant symptoms and were discharged following their scoliosis correction surgery. Syrinx was incidental in 14 further patients (Group II). Of the 14 patients, 11 remained asymptomatic with no change in syrinx morphology throughout follow up. Of the 14 patients, 3 were lost to follow-up. Of the 39 patients, 14 (Group III) presented with progressive back pain without any obvious clinical cause. Of the 14, 10 either improved or remained the same. Of the14 patients, 3 underwent lumbar puncture, 1/14 having myelography. All 4/14 patients reported significant pain reduction on follow up following intervention. Conclusion. Idiopathic syrinx is a benign pathology, which can be managed expectantly. Most cases remain stable or improve over time. In a small minority who have progressive back pain, we have found that lumbar puncture may be helpful in reducing symptoms.
British Journal of Neurosurgery 03/2013; · 0.88 Impact Factor
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ABSTRACT: Objectives It is widely accepted that the diagnosis of foetal central nervous system (CNS) abnormalities can be improved by performing MRI examinations in utero. Most of the published literature has concentrated on pregnancies in which a developmental abnormality has been detected (or suspected) on ultrasound in an otherwise low-risk pregnancy. In this paper, we test the hypothesis that in utero MRI of the foetal brain in high-risk pregnancies will detect abnormalities not shown by ultrasound at a rate that justifies its use in clinical practice. Methods 100 females were recruited into the study from foeto-maternal or clinical genetic departments. They all had a foetus/child with a CNS malformation from an earlier pregnancy, which led to an increased risk of recurrence being quoted for the present pregnancy. All in utero MRI examinations were performed on 1.5 T clinical MRI systems at 18 weeks gestational age or later. Results In 78% of cases, the ultrasound and MRI results agreed and showed no abnormality. In 13%, ultrasound and MRI described identical abnormal findings. In 9%, the ultrasound and MRI examinations had discrepant findings; in all these cases the MRI findings described more serious CNS pathology. The effects on management were judged to be major, by at least one assessor, in 7/9 of those cases. Conclusion As in many other situations involving antenatal detection of CNS abnormalities, in utero MRI should be considered in females with increased risk of foetal CNS malformation based on the results of an earlier pregnancy. Advances in knowledge In utero MRI of the foetus has an important role in antenatal diagnosis of females carrying a foetus with an increased risk of a brain abnormality.
The British journal of radiology 07/2012; 85(1019):e1038-45. · 2.11 Impact Factor
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ABSTRACT: To establish whether paediatric centres within the Children's Cancer and Leukaemia Group (CCLG) network employ magnetic resonance imaging (MRI) protocols for brain tumours according to the revised guidance.
Questionnaires were sent to both consultants and superintendent radiographers in the 21 centres within the CCLG network that perform MRI on paediatric brain tumour patients. Information was requested as to whether the centre had a protocol for imaging paediatric brain tumours, which sequences were performed, and whether these were used by all consultants.
Twenty-seven completed questionnaires out of the 42 sent were returned, which included responses from 17 of the 21 UK centres. The majority of centres had a protocol for MRI of paediatric brain tumours at all stages of treatment. The standardized CCLG MRI sequences were incorporated in full at only five of the 17 centres.
The standard sequences of the CCLG brain imaging protocol are poorly adhered to nationally. Further awareness of the revised protocol is needed, with improved access to the guidelines for non-CCLG members on the CCLG and Royal college of Radiologists website.
Clinical radiology 06/2012; 67(9):829-32. · 1.65 Impact Factor
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ABSTRACT: Clinical guidelines suggest that all patients diagnosed with localised seizures should be investigated with MRI to identify any epileptogenic structural lesions, as these patients may benefit from surgical resection. There is growing impetus to use higher field strength scanners to image such patients, as some evidence suggests that they improve detection rates. We set out to review the detection rate of radiological abnormalities found by imaging patients with localised seizures using a high-resolution 3.0 T epilepsy protocol.
Data were reviewed from 2000 consecutive adult patients with localisation-related epilepsy referred between January 2005 and February 2011, and imaged at 3.0 T using a standard epilepsy protocol.
An abnormality likely to be related to seizure activity was identified in 403/2000 (20.2%) patients, with mesial temporal sclerosis diagnosed in 211 patients. 313/2000 (15.6%) had lesions potentially amenable to surgery. Abnormalities thought unrelated to seizure activity were found in 324/2000 (16.1%), with 8.9% having evidence of ischaemic disease.
Since the introduction of the then National Institute for Clinical Excellence guidelines in 2004, the detection rate of significant pathology using a dedicated 3.0 T epilepsy protocol has not fallen, despite the increased numbers of patients being imaged. This is the largest study of epilepsy imaging at 3.0 T to date and highlights the detection rates of significant pathology in a clinical setting using a high-strength magnet. The prevalence of ischaemic disease in this population is significantly higher than first thought, and may not be incidental, as is often reported.
The British journal of radiology 05/2012; 85(1017):1236-42. · 2.11 Impact Factor
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ABSTRACT: To develop a neonatal MR-compatible incubator for transporting babies between a neonatal intensive care unit and an MRI unit that is within the same hospital but geographically separate.
The system was strapped to a standard MR-compatible patient trolley, which provides space for resuscitation outside the incubator. A constant-temperature exothermic heat pad was used to maintain temperature together with a logging fluoro-optic temperature monitor and alarm system. The system has been designed to accommodate standard knee-sized coils from the major MR manufacturers. The original incubator was constructed from carbon fibre, but this required modification to prevent radiofrequency shading artefacts due to the conducting properties of the carbon fibre. A high-tensile polyester material was used, which combined light weight with high impact strength. The system could be moved onto the patient bed with the coils and infant in place by one technologist.
Studies in eight neonatal patients produced high quality 1.5 T MR images with low motion artefacts. The incubator should also be compatible with imaging in 3 T MR systems, although further work is required to establish this. Images were acquired using both rapid and high-resolution sequences, including three-dimensional volumes, proton spectra and diffusion weighting.
The incubator provides a safe, quiet environment for neonates during transport and imaging, at low cost.
The British journal of radiology 12/2011; 85(1015):952-8. · 2.11 Impact Factor
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ABSTRACT: iuMR has been shown to increase the detection rate of developmental abnormalities of the CNS, though most reports are limited to singleton pregnancies. The hypothesis tested in this study was that iuMR performed in multifetal pregnancies will show additional information about fetal CNS abnormalities in a similar proportion of cases when compared with singleton pregnancies.
Fifty women with multifetal pregnancies were recruited consecutively carrying at least 1 fetus with a suspected developmental fetal CNS abnormality on sonography. All had iuMR at the same center by using the same MR imaging protocol. When the sonography and MR imaging reports were discrepant, 1 fetomaternal expert assessed the reports independently to predict in what percentage a change in prognosis/counseling would have occurred if iuMR was included in the diagnostic pathway.
There was agreement between the sonography and iuMR reports in 66% and disagreement in 34% of cases. The major cause for discrepancy was the presence or absence of the corpus callosum, which accounted for 10/17 of the disagreements. In 12/17 of the discrepant cases, the effect on management was judged to be significant.
We conclude that iuMR has a similar rate of discrepancy to sonography in multifetal pregnancies compared with the published data concerning singleton pregnancies. Our analysis of the effect on management shows that changes in the decision to consider termination of pregnancy would have occurred in 12/17 of the discrepant cases (ie, in 24% of our cases overall).
American Journal of Neuroradiology 11/2011; 33(2):359-65. · 2.93 Impact Factor
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ABSTRACT: Previous work using proton MR spectroscopy ((1)H-MRS) of the cerebellum in the ataxias suggested that (1)H-MRS abnormalities and atrophy do not necessarily occur concurrently.
To investigate the spectroscopic features of different types of ataxias.
Using a clinical MR system operating at 1.5T, we performed (1)H-MRS with a single voxel placed over the right dentate nucleus in 22 patients with gluten ataxia (GA), six patients with Friedreich's ataxia (FA), six patients with spinocerebellar ataxia type 6 (SCA6) and 21 healthy volunteers. Atrophy of the vermis and hemispheres on standard MRI was rated by a neuroradiologist. Any interaction between atrophy and (1)H-MRS was analysed for the three groups of patients and controls.
Patients with GA had significant atrophy of the vermis and hemispheres as well as abnormal (1)H-MRS. Patients with SCA6 had more severe overall atrophy of the vermis and hemispheres, but relatively preserved N-acetyl-aspartate/creatine (NAA/Cr). The FA group showed significant atrophy of only the superior vermis with normal (1)H-MRS.
This study suggests that (1)H-MRS of the cerebellum in patients with ataxia provides information in addition to the presence of atrophy. There are significant (1)H-MRS differences amongst different types of ataxia with interesting correlations between atrophy and NAA/Cr.
Acta Neurologica Scandinavica 11/2011; 126(2):138-43. · 2.47 Impact Factor
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ABSTRACT: Patients with epilepsy often have a structural cause for their seizures and may benefit from surgical resection. As recommended in the National Institute of Health and Clinical Excellence (NICE) guidelines, magnetic resonance imaging (MRI) is used to screen for structural abnormalities in these patients and there is increasing evidence that 3T MRI has better sensitivity and specificity than 1.5T. This article reviews the imaging findings of many of the common diseases that can cause epilepsy.
Clinical radiology 03/2011; 66(3):278-86. · 1.65 Impact Factor
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ABSTRACT: Head injury from physical abuse is unfortunately a common occurrence in our society. It is a major cause of mortality and long-term physical and psychological disability in children. Diagnosis of non-accidental head injury may be difficult, as most infants present with non-specific clinical findings and without external signs of trauma. Neuroimaging plays a fundamental role both for medical management and medicolegal aspects of child abuse. It is therefore imperative for the radiologist to promptly recognise the radiological findings of various forms of non-accidental head injury to render a more accurate opinion. A standardised imaging protocol and good communication between professionals are essential for optimum management.
Postgraduate medical journal 03/2011; 87(1027):355-61. · 1.38 Impact Factor
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ABSTRACT: Although MR imaging of the fetal brain has been shown to provide additional diagnostic information, the optimal timing of the study and the value of repeat studies remain unclear. The primary purpose of this study was to look for structural abnormalities of the fetal brain shown at 30-32 weeks' gestational age but not on the 20-24 weeks' study in fetuses originally referred with isolated VM. In particular, we wished to study the hypothesis that third-trimester fetal MR imaging studies would not show extra brain abnormalities compared with the second-trimester studies in this group.
Ninety-nine women were admitted for a fetal MR study between 20-24 weeks' gestational age, and 46 of these women agreed to return for a second MR imaging examination at 30-32 weeks' gestational age. The other women were either lost to follow-up or declined the invitation to return. Two experienced observers measured the width of the trigones, and the results were compared, to test reliability. Changes in the degree of VM are reported along with changes in the diagnosis of structural brain abnormalities.
There was excellent reproducibility of trigone measurements between the 2 observers, with a mean absolute difference of <1 mm in the 40 fetuses that were ultimately shown to have isolated VM. Twenty-eight of 40 fetuses studied had mild VM on the first iuMR imaging examination, but in just more than half, the category of VM changed between the studies (5 had become normal-sized, 7 had progressed to moderate, 3 had become severe, and 13 remained mild). In 1 case, hypogenesis of the corpus callosum was recognized at 30-32 weeks but had not been reported on the 20-24 weeks' examination; the other 5 fetuses had brain pathology recognized on both fetal MR studies.
Trigone measurements can be made in a highly repeatable fashion on iuMR imaging. We have not shown any major advantage in repeating iuMR imaging at 30-32 weeks' gestation in terms of improved diagnosis of other structural brain abnormalities. With the converse of that argument, however, our data suggest that there is no advantage in delaying iuMR imaging studies to 30-32 weeks in the hope of improving detection rates.
American Journal of Neuroradiology 12/2010; 32(3):474-80. · 2.93 Impact Factor
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ABSTRACT: Acute bacterial meningitis is a common neurological emergency and a leading cause of death and neurological disability worldwide. Diagnosis is based on clinical and microbiological findings with neuroimaging in the form of CT reserved for those with specific adverse clinical features or when an underlying cause such as mastoiditis is suspected. MRI is extremely useful for detecting and monitoring the complications of meningitis. These can be remembered by the mnemonic HACTIVE (hydrocephalus, abscess, cerebritis/cranial nerve lesion, thrombosis, infarct, ventriculitis/vasculopathy and extra-axial collection). Diffusion weighted imaging (DWI) and magnetic resonance spectroscopy (MRS) are useful to distinguish abscess from other ring enhancing lesions.
Postgraduate medical journal 08/2010; 86(1018):478-85. · 1.38 Impact Factor
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ABSTRACT: There is gathering evidence to suggest that agenesis of the corpus callosum is associated with delayed fetal sulcation; it is possible that the corpus callosum facilitates normal gyral development. In this paper we sought to confirm whether delayed sulcation is found in fetuses with isolated agenesis of the corpus callosum as judged by in utero MR imaging.
Retrospective analysis of 20 fetuses with isolated corpus callosum agenesis investigated by in utero MR imaging and 20 aged-matched normal fetuses was performed in the second or third trimester. All fetuses were singleton pregnancies with known gestational age, imaged on a 1.5T superconducting MR system. Estimation of sulcation maturity was made with reference to a standard atlas and subgroup analysis of earlier gestation (group 1, 21-26 weeks) and later gestation (group 2, 30-34 weeks) fetuses was performed.
Group 1 (n = 12) did not show a statistically significant difference between the 2 subgroups (P = .44) in terms of sulcation. A significant difference was demonstrated in the later gestation, group 2 (n = 8) fetal analyses; mean difference between consensus and actual gestation for normal fetuses was 0.9 weeks (SD of 1.5 weeks) versus -0.5 weeks (SD of 1.1 weeks) for the agenesis of corpus callosum cases (P = .046), suggestive of delayed sulcation in callosal agenesis.
Delayed sulcation encountered in third trimester fetuses with agenesis of the corpus callosum may be seen and does not in itself imply an additional brain abnormality.
American Journal of Neuroradiology 06/2010; 31(6):1085-90. · 2.93 Impact Factor
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ABSTRACT: Interpretation of CT of the anterior skull base in children depends on knowledge of the pattern and chronology of ossification. The purpose of this study was to ascertain the age at which the anterior cranial fossa is fully ossified as assessed on CT examinations.
This was a retrospective review of 127 CT examinations of children ranging from 1 day to 16 years 7 months of age without known or suspected anterior cranial fossa abnormality. Measurements of the length and width of the anterior skull base and the presence and size of the most anterior unossified portion were determined by 2 investigators.
At birth, the anterior skull base consists mainly of cartilage. There is a wide variation in ossification rates between individuals, but the anterior skull base was fully ossified at 3 years 10 months in all of our cases.
In healthy individuals, the anterior skull base is fully ossified by 4 years of age.
American Journal of Neuroradiology 04/2010; 31(7):1268-72. · 2.93 Impact Factor
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ABSTRACT: Imaging studies have shown that children with NF-1 have increased brain volumes compared with age-matched controls and the CCs are disproportionately large. The purpose of this study was to determine if the CC in adults with NF-1 differed from that in matched controls by using DTI and volumetric imaging.
MR imaging with DTI was performed in 10 adults with NF-1 and in 10 age-, sex-, and handedness-matched controls by using a 3T system. Total brain volumes and the areas and central lengths of the CC were calculated, along with the radial width of callosal subdivisions, in the 2 groups.
Our results showed that the total brain volume was not significantly different between adults with NF-1 and matched controls. The length and total cross-sectional area of the CC were statistically larger in adults with NF-1 compared with controls (approximately 10% longer and 20% greater area). On DTI we found a preservation of the primary eigenvalue with increases in the minor eigenvalues at the genu.
We have shown that the increased size of the CC found in children with NF-1 is also present in adults with the syndrome, whereas no difference in total brain volume was found.
American Journal of Neuroradiology 03/2010; 31(5):856-61. · 2.93 Impact Factor
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Ultrasound in Obstetrics and Gynecology 10/2009; 34(S1):113-114. · 3.01 Impact Factor
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ABSTRACT: To evaluate the discrepancy rate among specialist registrars (SPR) to assess whether seniority had a bearing on the discrepancy rate. To investigate which were the commonly missed abnormalities and the consequences for teaching purposes. To investigate the role of a specialist consultant neuroradiologist in reporting paediatric head computed tomography examinations.
The study was carried out over a 9-month period at the regional paediatric hospital during which time 270 CT head examinations were reported. Reporting in the department is carried out by one of the five general paediatric radiologists (GR) and also a specialist paediatric neuroradiologist (NR). The NR was considered the reference standard, who corroborated in areas of discrepancy with a second senior NR for this study. Of the 270 examinations, 260 were reported by the paediatric NR, 160 were reported by the SPR, GR, and NR, and 51 were reported by an SPR and the NR. In addition, four were reported by the GR and the NR, 45 by the NR only, seven by the GR only, and three cases were reported by the GR and an SPR. The discrepancy rates were calculated for GR versus NR, and SPR versus NR. All the discrepancies were re-evaluated by a second senior NR and confirmed in all cases. The reports of the SPR were further scrutinized. The trainees of training years 1-3 were considered junior and 4-5 were considered senior.
There was a discrepancy in 26/164 cases (15.9%) reported by the GR and NR. There was a discrepancy in 59/211 cases (28%) reported by an SPR and NR. The chi-squared test (two-sided) showed a significant difference (p=0.005) between the two groups. There was a discrepancy in 36/118 cases (30.5%) reported by the junior SPR and NR. There was a discrepancy in 23/93 cases (24.7%) reported by a senior SPR and NR. The chi-squared test (two-sided) showed a non-significant difference (p=0.353) between the two groups.
The performance of the SPR was considered to be significantly different than the GR in this study. The year of training did not have a statistically significant bearing on the discrepancy rates. This study has been useful in guiding SPR with regards to paediatric CT head examination reporting. The NR played an important role, particularly in picking up subtle fractures and congenital abnormalities, which were missed by both the SPR and GR.
Clinical radiology 10/2009; 64(9):891-6. · 1.65 Impact Factor
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ABSTRACT: Fetal ventriculomegaly (VM) is important because of its high prevalence and high risk of association with other brain abnormalities. The purpose of this article was to investigate the hypotheses that including in utero MR imaging (iuMR) in the diagnostic pathway for fetuses with isolated VM on antenatal imaging will show other brain abnormalities in a high proportion of cases and that these will have a significant effect on clinical management.
One hundred forty-seven pregnant women were recruited prospectively from 8 fetomaternal centers in Britain. All of the fetuses had VM diagnosed on sonography but no other abnormality. iuMR was performed, and the results of the examinations were compared with those of sonography. Two fetomaternal experts made independent assessments of the effects of any new diagnoses on clinical management.
Categoric assessments of ventricular size were the same in approximately 90% of fetuses. Other abnormalities were shown in 17% of fetuses. The most frequent additional brain abnormality shown on iuMR was agenesis of the corpus callosum. Severe VM was associated with an approximately 10-fold increase in the risk of another brain abnormality being present when compared with fetuses with mild VM. The most profound effects on clinical management, however, were found in cases of mild VM.
This work supports our hypotheses by showing a high detection rate of other brain pathology when iuMR was used to supplement antenatal sonography (17%). In a high proportion of cases, the detection of the extra pathology would have led to significant changes in clinical management.
American Journal of Neuroradiology 09/2009; 31(1):106-11. · 2.93 Impact Factor
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ABSTRACT: This study aimed (1) to image clinically normal newborn infants to detect the presence of any intracranial bleed and (2) to establish the natural history of the bleed. Newborn babies were imaged within 48 hours of delivery and all details of the labour and delivery were recorded. MR imaging was carried out on a dedicated 0.2T Niche MR system on the special care baby unit. Images were obtained in axial and coronal planes using T1, T2 plus gradient echo weighted images; similarly for the follow-up imaging. χ2 test was used for analysis. One hundred and two newborn infants were scanned. Forty-five had a normal vaginal delivery, 10 were ventouse (three metal cup, seven silastic), 10 were emergency sections, 15 were elective sections, 22 were forceps (19 Neville Barnes, three Keillands). Five had subdural collections that were clinically silent throughout their duration and had resolved fully within 4 weeks.All five babies with subdural collections had been delivered by forceps following an attempt at a ventouse delivery. In total 15 babies were delivered by forceps following a ventouse delivery and one by emergency caesarian section following an attempted ventouse delivery. The method of delivery was the only statistically significant factor in these babies (duration of labour, fetal blood pH, etc. were not statistically significant) for the presence of a subdural collection, using the χ2 test (P < 0.001).
07/2009; 23(s1):S20-S20.
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ABSTRACT: The purpose of this study was to assess the success of neurolinguistic programming in reducing the need for general anaesthesia in claustrophobic patients who require MRI and to consider the financial implications for health providers. This was a prospective study performed in 2006 and 2007 at a teaching hospital in England and comprised 50 adults who had unsuccessful MR examinations because of claustrophobia. The main outcome measures were the ability to tolerate a successful MR examination after neurolinguistic programming, the reduction of median anxiety scores produced by neurolinguistic programming, and models of costs for various imaging pathways. Neurolinguistic programming allowed 38/50 people (76%) to complete the MR examination successfully. Overall, the median anxiety score was significantly reduced following the session of neurolinguistic programming. In conclusion, neurolinguistic programming reduced anxiety and subsequently allowed MRI to be performed without resorting to general anaesthesia in a high proportion of claustrophobic adults. If these results are reproducible, there will be major advantages in terms of patient safety and costs.
The British journal of radiology 07/2009; 83(986):113-7. · 2.11 Impact Factor
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ABSTRACT: We were finding volunteers for functional magnetic resonance imaging studies with abnormalities requiring referral surprisingly frequently. The bioethics surrounding the incidental findings are not straightforward and every imaging institution will encounter this situation in their normal volunteers. Yet the implications for the individuals involved may be profound. Should all participants have review of their imaging by an expert and who should be informed?
The normal volunteers that were imaged with magnetic resonance (MR) which were reviewed by a consultant neuroradiologist. All participants completed a volunteer consent form in addition to a standard departmental MR safety screening form. The volunteer screening form requires the general practitioner details to be completed and asks the participant to consider closely the possibility and implications of finding an unexpected but potentially serious abnormality before signing.
525 different individuals were scanned as normal volunteers, the mean age was 35-years and 330 were males. Of these 525, 46 had definite significant abnormalities (8.8%), mean age 50-years.
We have found a high rate of incidental abnormalities amongst individuals participating in imaging studies at our institution. It is our current practice to inform the research study participant of the findings, counsel them and inform their primary care physician. We think that it is advisable for researchers utilising MR imaging of the brain to have access to trained neuroradiologists, a protocol in place to deal with this problem and take consent in a way that allows the participant to realise the possibility of an abnormal finding.
Journal of medical ethics 04/2009; 35(3):194-9. · 1.21 Impact Factor
