Sussex Research Online: No conditions. Results ordered -Date Deposited. 2023-11-17T15:36:23Z EPrints https://sro.sussex.ac.uk/images/sitelogo.png http://sro.sussex.ac.uk/ 2015-09-11T15:02:29Z 2019-07-02T18:01:13Z http://sro.sussex.ac.uk/id/eprint/56672 This item is in the repository with the URL: http://sro.sussex.ac.uk/id/eprint/56672 2015-09-11T15:02:29Z The effect of alcohol and repetition at encoding on implicit and explicit false memories

Rationale Alcohol impairs explicit memory, whilst leaving
implicit memory relatively intact. Less is known about its
effects on false memories.
Aim The present study examines the effects of alcohol on
explicit and implicit false memories using study list
repetition as a tool for modulating learning at encoding.
Methods Thirty-two participants were given either an
alcohol (0.6 g/kg) or placebo beverage before undergoing
an encoding phase consisting of 10 lists of nine associated
words (veridical items). Each list was associated to a word,
which was not presented at encoding (semantically associated
non-studied lure; critical item), serving as the measure
for false memory. Half of the lists were presented once, and
half were repeated three times. The next day, participants
underwent an implicit (stem completion and post hoc
awareness measurements), and an explicit (free recall) task.
Results Alcohol decreased veridical and false explicit
memory for singularly presented lists compared to placebo;
no group difference existed for repeated lists. Implicit
veridical memory was not affected by alcohol. Awareness
memory measures demonstrated in placebo participants an
increased ability with repetition in rejecting false memories.
The reverse was found in intoxicated participants who with
repetition accepted more false memories.
Conclusion Alcohol appears to decrease semantic activation
leading to a decline in false memories. Increased
learning with repetition, which increases the rejection of
false memories under placebo, is reversed under alcohol
leading to a decrease in rejection of false memories. The
latter effect of alcohol may be due to its ability to impair
monitoring processes established at encoding.

S N Garfinkel 103603 Z Dienes T Duka
2015-08-20T13:44:48Z 2019-07-02T22:35:10Z http://sro.sussex.ac.uk/id/eprint/56200 This item is in the repository with the URL: http://sro.sussex.ac.uk/id/eprint/56200 2015-08-20T13:44:48Z How metaphors influence semantic relatedness judgments: the role of the right frontal cortex

We used event-related fMRI (ER-fMRI) to test the hypothesis that metaphors bias cognitive processing of semantic relatedness towards a search for a wider range of associations. Twelve right-handed male
volunteers read a mixture of metaphoric and literal sentences, each sentence being followed by a single word, which could be semantically
related or not to the preceding sentence context. We found that judging unrelated words as contextually irrelevant was associated with increased blood oxygenation level-dependent (BOLD) signal in the right ventrolateral prefrontal cortex in the metaphoric but not in the literal condition. The same region was also activated when subjects endorsed a semantic relation between words and metaphoric sentence primes but not between words and literal sentence primes.
We argue that these results are consistent with the notion of semantic open-endedness, whereby figurative statements bias cognitive processing towards a search for a wider range of semantic relationships compared to literal statements, and thus lend further support to the view that coarse semantic coding occurs preferentially in the right
hemisphere.

Argyris Stringaris Nicholas Medford 220234 Rachel Giora Vincent Giampietro Michael Brammer Anthony. S David
2015-08-20T13:22:51Z 2019-07-02T22:35:08Z http://sro.sussex.ac.uk/id/eprint/56195 This item is in the repository with the URL: http://sro.sussex.ac.uk/id/eprint/56195 2015-08-20T13:22:51Z Understanding and treating depersonalisation disorder: a functional MRI study

This study examines emotional memory effects in primary depersonalization disorder (DPD). A core complaint of DPD sufferers is the dulling of emotional responses, and previous work has shown that, in response to aversive stimuli, DPD patients do not show activation of brain regions involved in normal emotional processing. We hypothesized that DPD sufferers would not show the normal emotional enhancement of memory, and that they would not show activation of brain regions concerned with emotional processing during encoding and recognition of emotional verbal material. Using fMRI, 10 DPD patients were compared with an age-matched healthy control group while performing a test of emotional verbal memory, comprising one encoding and two recognition memory tasks. DPD patients showed significantly enhanced recognition for overtly emotive words, but did not show enhancement of memory for neutral words encoded in an emotive context. In addition, patients did not show activation of emotional processing areas during encoding, and exhibited no substantial difference in their neural responses to emotional and neutral material in the encoding and emotional word recognition tasks. This study provides further evidence that patients with DPD do not process emotionally salient material in the same way as healthy controls, in accordance with their subjective descriptions of reduced or absent emotional responses.
© 2006 Elsevier Ireland Ltd. All rights reserved.

Nicholas Medford 220234 Barbara Brierley Michael Brammer Edward Bullmore Anthony David Mary Phillips
2015-08-06T13:43:15Z 2019-07-02T18:01:21Z http://sro.sussex.ac.uk/id/eprint/56013 This item is in the repository with the URL: http://sro.sussex.ac.uk/id/eprint/56013 2015-08-06T13:43:15Z Social and emotional functions in three patients with medial frontal lobe damage including the anterior cingulate cortex

Introduction. The aim of this study was to explore social and emotional functions in patients with medial frontal damage including the anterior cingulate cortex (ACC).

Methods. Three patients with medial frontal lobe lesions primarily involving the ACC performed tasks on motivational decision making, emotional facial expression recognition, and social cognition, including theory of mind (ToM). Their performance on these tasks was compared with age and education matched healthy controls.

Results. Patient performance on the motivational decision making and social situations tasks did not differ from controls. Selective emotional facial expression recognition impairment for fear was evident in one patient with a unilateral right ACC lesion (patient 3). ToM impairment was present in only one patient with a bilateral ACC lesion (patient 2). In contrast, the two patients with unilateral right ACC lesions had intact ToM (patients 1 and 3).

Conclusions. These findings suggest that medial frontal lobe lesions primarily involving the ACC do not appear to critically disrupt motivational decision making or social situation processing. The ACC plays a role in processing particular types of emotion (fear). Bilateral ACC damage impairs ToM processing, but unilateral damage to the right ACC is not sufficient to disrupt ToM.

Amee Baird Bonnie‐Kate Dewar Hugo Critchley 198138 Ray Dolan Tim Shallice Lisa Cipolotti
2014-05-12T12:41:22Z 2017-09-21T11:58:36Z http://sro.sussex.ac.uk/id/eprint/48377 This item is in the repository with the URL: http://sro.sussex.ac.uk/id/eprint/48377 2014-05-12T12:41:22Z Dissociation between tuberculin skin test and in vitro IFN-gamma responses following neonatal BCG vaccination

The in vitro IFN-gamma response to tuberculin was recently proposed as a correlate of vaccine-induced immunity to tuberculosis. IFN-gamma also plays a central role in the tuberculin skin test (TST), commonly used as a marker of mycobacterial infection. However, the use of TST as a marker of immunity to tuberculosis is limited for reasons ascribed mainly to interference by environmental mycobacteria. We prospectively investigated the relationship between the TST and cytokine responses to BCG in early infancy, a cohort with relatively low exposure to environmental mycobacteria. Neonatal BCG vaccination induced positive TST responses and predominant IFN-gamma responses to tuberculin in most newborns. However, the production of IFN-gamma, IL-5 and IL-13 was similar in TST responders and non-responders, and there was no significant correlation between the size of TST response and cytokine production. These results indicate that the IFN-gamma assay provides different information than TST in BCG-vaccinated newborns and could be a better marker of vaccine-induced immunity.

Martin O C Ota Tessa Goetghebuer Johan Vekemans Brown J Okoko Melanie J Newport 174794 Keith P W J McAdam Arnaud Marchant
2012-02-21T10:04:52Z 2020-01-10T11:47:37Z http://sro.sussex.ac.uk/id/eprint/38068 This item is in the repository with the URL: http://sro.sussex.ac.uk/id/eprint/38068 2012-02-21T10:04:52Z Allergy and clinical immunology services in Europe

Allergology and Clinical Immunology (ACI) is an area of clinical medicine with a precise identity, relevant recent scientific achievements and well‐defined educational and professional needs.

In spite of the high individual and socio‐economic impact of allergic diseases in Europe, the organization of ACI services is imperfect and varies among countries according to their health policies and priorities.

In the firm belief of the role of ACI specialists in addressing clinical issues related to the involvement of the immune system in health and diseases—such as vaccination, immunodeficiencies, susceptibility and response to microbial agents, autoimmune and allergic diseases, immune aspects of transplantation and malignancies, in vivo and in vitro immunological tests, vaccinations, immuno‐modifiers—the European Academy of Allergology and Clinical Immunology appointed an ad hoc Task Force to produce standards for ACI Services in Europe.

The resulting position paper should be used as a consulting reference for National Health Services as a necessary pre‐requisite for the free circulation to patients and health care professionals.

S Bonini IJ Ansotegui S Durham A J Frew 143875 J Lötvall K Nekham T Popov R Dahl J Gayraud R Gerth van Wijk K Kontou-Fili M Kowalski A Todo-Bon U Wahn
2010-04-08Z 2019-07-02T21:05:38Z http://sro.sussex.ac.uk/id/eprint/2284 This item is in the repository with the URL: http://sro.sussex.ac.uk/id/eprint/2284 2010-04-08Z End-of-life care in the community hospitals: the perceptions of bereaved family members

Objectives: The perceptions of bereaved family members were obtained to evaluate the nature and quality of end-of-life care in community hospitals. Design: During organizational case studies in six community hospitals in the South East and South West of England, bereaved family members were asked to participate in semi-structured interviews. Participants: Fifty-one interviews were conducted with family members of patients who had received end-of-life care in a community hospital within the previous year. Results: Respondents were very positive about the care they and the patient had received. They valued the convenience of access for frequent and long-stay visiting and the familiarity of the local hospital. Comparisons were made with more negative experiences at their nearest District General Hospital. Issues raised included the noise at the community hospitals, and the lack of contact with qualified nurses. Discussion: The results of this study have implications for UK government initiatives, such as the National Framework for Older People,1 and the Department of Health's ‘Keeping the NHS Local’2.

Sheila Hawker Chris Kerr Sheila Payne David Seamark Carol Davis Helen Roberts Nicola Jarrett Paul Roderick Helen Smith 151947
2010-04-08Z 2019-07-02T21:05:36Z http://sro.sussex.ac.uk/id/eprint/2285 This item is in the repository with the URL: http://sro.sussex.ac.uk/id/eprint/2285 2010-04-08Z Developing clinical rules to predict urinary tract infection in primary care settings: sensitivity and specificity of near patient tests (dipsticks) and clinical scores

Background Suspected urinary tract infection (UTI) is one of the most common presentations in primary care. Systematic reviews have not documented any adequately powered studies in primary care that assess independent predictors of laboratory diagnosis. Aim To estimate independent clinical and dipstick predictors of infection and to develop clinical decision rules. Design of study Validation study of clinical and dipstick findings compared with laboratory testing. Setting General practices in the south of England. Method Laboratory diagnosis of 427 women with suspected UTI was assessed using European urinalysis guidelines. Independent clinical and dipstick predictors of diagnosis were estimated. Results UTI was confirmed in 62.5% of women with suspected UTI. Only nitrite, leucocyte esterase (+ or greater), and blood (haemolysed trace or greater) independently predicted diagnosis (adjusted odds ratios 6.36, 4.52, 2.23 respectively). A dipstick decision rule, based on having nitrite, or both leucocytes and blood, was moderately sensitive (77%) and specific (70%); positive predictive value (PPV) was 81% and negative predictive value (NPV) was 65%. Predictive values were improved by varying the cut-off point: NPV was 73% for all three dipstick results being negative, and PPV was 92% for having nitrite and either blood or leucocyte esterase. A clinical decision rule, based on having two of the following: urine cloudiness, offensive smell, and dysuria and/or nocturia of moderate severity, was less sensitive (65%) (specificity 69%; PPV 77%, NPV 54%). NPV was 71% for none of the four clinical features, and the PPV was 84% for three or more features. Conclusions Simple decision rules could improve targeting of investigation and treatment. Strategies to use such rules need to take into account limited negative predictive value, which is lower than expected from previous research.

Paul Little Sheila Turner Kate Rumsby Greg Warner Michael. J Moore Andrew Lowes Helen Smith 151947 Catherine Hawke Mark Mullee
2008-07-17Z 2013-06-19T13:45:12Z http://sro.sussex.ac.uk/id/eprint/1818 This item is in the repository with the URL: http://sro.sussex.ac.uk/id/eprint/1818 2008-07-17Z Attitudes and uptake of a screening test: the moderating role of ambivalence Elizabeth Dormandy Matthew Hankins 179951 Theresa M Marteau 2007-06-19Z 2019-09-16T14:23:40Z http://sro.sussex.ac.uk/id/eprint/1192 This item is in the repository with the URL: http://sro.sussex.ac.uk/id/eprint/1192 2007-06-19Z Emotional and autonomic consequences of spinal cord injury explored using functional brain imaging

In health, emotions are integrated with autonomic bodily responses. Emotional stimuli elicit changes in somatic (including autonomic) bodily states, which feedback to influence the expression of emotional feelings. In patients with spinal cord injury (SCI), this integration of emotion and bodily arousal is partially disrupted, impairing both efferent generation of sympathetic responses and afferent sensory feedback of visceral state via the spinal cord. A number of theoretical accounts of emotion predict emotional deficits in SCI patients, particularly at the level of emotional feelings, yet evidence for such a deficit is equivocal. We used functional MRI (fMRI) and a basic emotional learning paradigm to investigate the expression of emotion-related brain activity consequent upon SCI. We scanned seven SCI patients and seven healthy controls during an aversive fear conditioning task. Subjects viewed randomized presentations of four angry faces. One of the faces (CS + arm) was associated with delivery of electrical shock to the upper arm on 50% of trials. This shock was painful to all subjects. A face of the same gender acted as a safe' control stimulus (CS - arm). In both control subjects and SCI patients, painful cutaneous stimulation of the arm evoked enhanced activity within components of a central pain matrix, including dorsal anterior cingulate, right insula and medial temporal lobe. However, SCI patients differed from controls in conditioning-related brain activity. SCI patients showed a relative enhancement of activity within dorsal anterior cingulate, periaqueductal grey matter (PAG) and superior temporal gyrus. Conversely, SCI patients showed relative attenuation of activity in subgenual cingulate, ventromedial prefrontal and posterior cingulate cortices to threat of painful arm stimulation (CS + arm > CS - arm). Our findings provide evidence for differences in emotion-related brain activity in SCI patients. We suggest that the observed functional abnormalities including enhanced anterior cingulate and PAG reflect central sensitization of the pain matrix, while decreased subgenual cingulate activity may represent a substrate underlying affective vulnerability in SCI patients consequent upon perturbation of autonomic control and afferent visceral representation. Together these observations may account for motivational and affective sequelae of SCI in some individuals.

Alessia Nicotra Hugo D Critchley 198138 Christopher J Mathias Raymond J Dolan
2007-06-15Z 2019-09-16T14:07:13Z http://sro.sussex.ac.uk/id/eprint/1188 This item is in the repository with the URL: http://sro.sussex.ac.uk/id/eprint/1188 2007-06-15Z A patient with both Gilles de la Tourette's syndrome and chromosome 22q11 deletion syndrome: clue to the genetics of Gilles de la Tourette's syndrome?

This is the first published case description of the association of Gilles de la Tourette's syndrome (GTS) and chromosome 22q11.2 deletion syndrome (22q11DS; previously referred to as CATCH-22 syndrome). The co-occurrence of GTS, 22q11DS, and their behavioral/neuropsychiatric abnormalities may be due to the common endophenotypic mechanisms shared by these disorders, rather than due to specificity for GTS. Research into this genomic region may lead to advancement in neurobehavioral/neuropsychiatric genetics, which will help us in further explicating a broader perspective of gene–brain–behavior interrelationships and of the genetic underpinnings of various developmental psychopathologies and behavioral/neuropsychiatric disorders that are common to both GTS and 22q11DS. Our report should warrant further genetic investigations of the chromosome 22q11.2 deletion site using alternative strategies to the quantitative trait loci endophenotype-based approach, which would be useful for establishing the biological and molecular underpinnings of obsessive–compulsive disorder, attention-deficit/hyperactivity disorder, and GTS.

Mary M Robertson Bhaskara Pillai Shelley Suraiya Dalwai Carole Brewer Hugo D Critchley 198138
2007-03-30Z 2018-05-23T14:32:46Z http://sro.sussex.ac.uk/id/eprint/1135 This item is in the repository with the URL: http://sro.sussex.ac.uk/id/eprint/1135 2007-03-30Z Trends in sexually transmitted infections in general practice 1990-2000: population based study using data from the UK general practice research database

OBJECTIVE: To describe the contribution of primary care to the diagnosis and management of sexually transmitted infections in the United Kingdom, 1990-2000, in the context of increasing incidence of infections in genitourinary medicine clinics. DESIGN: Population based study. SETTING: UK primary care. PARTICIPANTS: Patients registered in the UK general practice research database. MAIN OUTCOME MEASURES: Incidence of diagnosed sexually transmitted infections in primary care and estimation of the proportion of major such infections diagnosed in primary care. RESULTS: An estimated 23.0% of chlamydia cases in women but only 5.3% in men were diagnosed and treated in primary care during 1998-2000, along with 49.2% cases of non-specific urethritis and urethral discharge in men and 5.7% cases of gonorrhoea in women and 2.9% in men. Rates of diagnosis in primary care rose substantially in the late 1990s. CONCLUSIONS: A substantial and increasing number of sexually transmitted infections are diagnosed and treated in primary care in the United Kingdom, with sex ratios differing from those in genitourinary medicine clinics. Large numbers of men are treated in primary care for presumptive sexually transmitted infections.

Jackie A Cassell 16624 Catherine H Mercer Lorna Sutcliffe Irene Petersen Amire Islam M Gary Brook Jonathan D Ross George R Kinghorn Ian Simms Gwenda Hughes Azeem Majeed Judith M Stephenson Anne M Johnson Andrew C Hayward
2007-03-30Z 2018-05-23T14:29:58Z http://sro.sussex.ac.uk/id/eprint/1137 This item is in the repository with the URL: http://sro.sussex.ac.uk/id/eprint/1137 2007-03-30Z The social shaping of childhood vaccination practice in rural and urban Gambia

Improving childhood vaccination coverage is a key health policy objective in Africa, and as availability increases, it will depend on addressing issues of demand and timely schedule completion. This paper explores vaccination demand in urban and rural areas of The Gambia as shaped by prevailing local vaccination cultures (comprising maternal knowledge and understandings, socio-cultural contexts and interactions with health providers). A survey of 1,600 mothers constructed on the basis of prior ethnography finds a high level of social demand for vaccination, based on lay theories of the general value of immunization in complementing traditional child protection practices. For most rural mothers, strong social networks encourage routine clinic attendance and vaccination 'default' arises only through day-to-day problems and contingencies. However, more pervasive patterns of schedule non-completion are found amongst poorer urban mothers, including recent immigrants, who experience social exclusion at infant welfare clinics. These findings point to the need for health education dialogue grounded in mothers' own understandings and for particular policy attention to improving the clinic experiences of vulnerable social groups in rapidly expanding urban areas.

J A Cassell 16624 M Leach J R Fairhead M Small C H Mercer
2007-03-30Z 2017-09-28T14:06:14Z http://sro.sussex.ac.uk/id/eprint/1139 This item is in the repository with the URL: http://sro.sussex.ac.uk/id/eprint/1139 2007-03-30Z Who uses condoms with whom? Evidence from national probability sample surveys

OBJECTIVES: To explore the changing pattern of condom use from 1990 to 2000; to identify sociodemographic and behavioural factors associated with condom use; and reasons for condom use in 2000. METHODS: Large probability sample surveys administered among those resident in Britain aged 16-44 (n = 13 765 in 1990, n = 11 161 in 2000). Face to face interviews with self completion components collected sociodemographic, behavioural, and attitudinal data. RESULTS: Condom use in the past year among sexually active 16-24 year old men increased from 61.0% in 1990 to 82.1% in 2000 (p<0.0001), and from 42.0% to 63.2% (p<0.0001) among women of the same age, with smaller increases among older age groups. Among individuals reporting at least two partners in the previous 4 week period, approximately two thirds reported inconsistent or no condom use (63.1% (95% CI 55.9% to 69.8%) of the men and 68.5% (95% CI 57.6% to 77.7%) of the women). CONCLUSIONS: Rates of condom use increased substantially between 1990 and 2000, particularly among young people. However, inconsistent condom use by individuals with high rates of partner acquisition may contribute significantly to the recent resurgence in STIs. This group is an important target for intensive and specific sexual health interventions.

J A Cassell 16624 C H Mercer J Imrie A J Copas A M Johnson
2007-02-28Z 2019-09-03T08:39:36Z http://sro.sussex.ac.uk/id/eprint/801 This item is in the repository with the URL: http://sro.sussex.ac.uk/id/eprint/801 2007-02-28Z Principal component and linear discriminant analysis of T1 histograms of white and grey matter in multiple sclerosis

Twenty-three relapsing remitting multiple sclerosis (RRMS) patients and 14 controls were imaged to produce normal-appearing white and grey matter T1 histograms. These were used to assess whether histogram measures from principal component analysis (PCA) and linear discriminant analysis (LDA) out-perform traditional histogram metrics in classification of T1 histograms into control and RRMS subject groups and in correlation with the expanded disability status score (EDSS). The histograms were classified into one of two groups using a leave-one-out analysis. In addition, the patients were scanned serially, and the calculated parameters correlated with the EDSS. The classification results showed that the more complex techniques were at least as good at classifying the subjects as histogram mean, peak height and peak location, with PCA/LDA having success rates of 76% for white matter and 68%/65% for grey matter. No significant correlations were found with EDSS for any histogram parameter. These results indicate that there is much information contained within the grey matter as well as the white matter histograms. Although in these histograms PCA and LDA did not add greatly to the discriminatory power of traditional histogram parameters, they provide marginally better performance, while relying only on data-driven feature selection.

D. J Tozer G. R. Davies D. R. Altmann D. H. Miller P. S. Tofts 49938
2007-02-28Z 2019-09-03T08:49:43Z http://sro.sussex.ac.uk/id/eprint/802 This item is in the repository with the URL: http://sro.sussex.ac.uk/id/eprint/802 2007-02-28Z Sources of variation in multi-centre brain MTR histogram studies: body-coil transmission eliminates inter-centre differences

OBJECT:
1. Identify sources of variation affecting Magnetisation Transfer Ratio (MTR) histogram reproducibility between-centres.
2. Demonstrate complete elimination of inter-centre difference.
MATERIALS AND METHODS: Six principle sources of variation were summarised and analysed. These are: the imager coil used for radiofrequency (RF) transmission, imager stability, the shape and other parameters describing the Magnetisation Transfer (MT) pulse, the MT sequence used (including its parameters), the image segmentation methodology, and the histogram generation technique. Transmit field nonuniformity and B1 errors are often the largest factors. PLUMB (Peak Location Uniformity in MTR histograms of the Brain) plots are a convenient way of visualising differences. Five multi-centres studies were undertaken to investigate and minimise differences.
RESULTS: Transmission using a body coil, with a close-fitting array of surface coils for reception, gave the best uniformity. Differences between two centres, having MR imagers from different manufacturers, were completely eliminated by using body coil excitation, making a small adjustment to the MT pulse flip angle, and carrying out segmentation at a single centre. Histograms and their peak location and height values were indistinguishable. CONCLUSIONS: Body coil excitation is preferred for multi-centre studies. Analysis (segmentation and histogram generation) should ideally be carried out at a single site.

P. S. Tofts 49938 S. C. Steens M. Cercignani F. Admiraal-Behloul P. A. Hofman M. J. van Osch W. M. Teeuwisse D. J. Tozer J. H. van Waesberghe R. Yeung G. J. Barker M. A. van Buchem
2007-02-28Z 2019-09-03T08:57:39Z http://sro.sussex.ac.uk/id/eprint/803 This item is in the repository with the URL: http://sro.sussex.ac.uk/id/eprint/803 2007-02-28Z 1H-MRS internal thermometry in test-objects (phantoms) to within 0.1 K for quality assurance in long-term quantitative MR studies

Many magnetic resonance test-object properties are temperature-dependent, with typical temperature coefficients of approximately 2-3% K(-1). Therefore, to achieve consistent quality assurance measurements to within 1%, test object temperatures should ideally be known to within 0.3 K. Proton magnetic resonance spectroscopy has previously been used to estimate accurately absolute tissue temperature in vivo, based on the linear temperature dependence of the chemical shift difference between water and temperature-stable reference metabolites such as N-acetylaspartate. In this study, this method of 'internal thermometry' in quality assurance test-objects was investigated, and in particular the value of sodium 3-(trimethylsilyl)propane-1-sulfonate (DSS) as a chemical shift reference was demonstrated. The relationship between the DSS-water chemical shift difference (sigma, expressed in ppm) and temperature tau (in K) was shown to be tau = 764.55 (+/-5.05) - 97.72 (+/-1.05) sigma (286 <or= tau <or= 309 K). Internal thermometry in MRI test-objects is feasible and straightforward, using readily available (1)H-MRS pulse sequences and standard spectroscopy evaluation packages, with a minimum detectable temperature difference of 100 (+/-20) mK.

R. S. Samson J. S. Thornton M. A. McLean S. C. Williams P. S. Tofts 49938
2007-02-28Z 2019-09-03T09:06:13Z http://sro.sussex.ac.uk/id/eprint/804 This item is in the repository with the URL: http://sro.sussex.ac.uk/id/eprint/804 2007-02-28Z A simple correction for B1 field errors in magnetization transfer ratio measurements

B1 errors are a problem in magnetization transfer ratio (MTR) measurements because the MTR value is dependent on the amplitude of the magnetization transfer (MT) pulse. B1 errors can arise from radiofrequency (RF) nonuniformity (caused by the RF coil, or skin effect and dielectric resonance in the subject's head) and also from inaccurate setting of the transmitter output when compensating for varying amounts of loading of the RF coil. B1 errors, and hence MTR errors, may be up to 5-10%, a large source of error in quantitative MR measurements. Radiofrequency nonuniformity may cause MTR histograms to be broadened. The dependence of MTR on B1 was modeled using binary spin bath theory, with a continuous wave (CW) approximation. For B1 reductions of up to 20%, normalized plots for different brain tissue types could be approximated by a single line, indicating that a systematic correction could be applied to MTR measurements with a known B1 error, regardless of tissue type. On a 1.5-T scanner with a birdcage coil, MTR was measured in 18 tissue types in five controls. The MT pulse amplitude was reduced in steps from its nominal value by up to 20%. Averaging data over all controls and tissue types resulted in a line fitting mtr(normalized)=0.812b(1normalized)+0.193, where mtr(normalized) is the normalized value of MTR (relative to its value at the nominal B1) and b(1normalized) is the normalized value of B1 (relative to its nominal value). For a 20% reduction in MT pulse amplitude (i.e., b(1normalized)=0.80), the mean MTR value for the 18 tissue types was 7.0 percent units (pu) below the correct value. After correction using the single equation above for all tissue types, all MTR values were within 1.5 pu of their correct value [root mean square (rms) error=0.7 pu]. Magnetization transfer ratio values tended to be slightly overcorrected because the simple linear correction scheme is only an approximation to the true MTR dependence on B1. A B1 field mapping technique was implemented, based on the double angle method (DAM), with fast spin-echo (FSE) readout, and TR=15 s; this took a total of 6 min of imaging time. This was used to quantify B(1) errors and correct MTR maps and histograms. However, the cerebrospinal fluid (CSF) T1 is very long (approximately 4.2 s); thus, to achieve complete longitudinal relaxation (a requirement of the DAM B1 mapping method), an increase in TR and, hence, acquisition time would be required. In general, however, we are not interested in calculating the B1 in the CSF, although it is important that the B1 is determined in partial volume voxels around the CSF. Using our birdcage head coil, whole-brain B1 histograms were found to have full-width half maximums (FWHMs) ranging from just 6.8% to 11.5% of the nominal B1 value. The FSE DAM B1 field mapping technique was shown to be robust, although a longer TR time may be desirable to ensure complete elimination of CSF partial volume errors. The procedure can be applied on any scanner where the Euro-MT sequence is available, or alternatively, where the amplitude of B1 or of the MT pulse can be manually reduced in order to perform this type of "calibration" experiment for the particular MTR sequence used. The MTR is known to be highly dependent on the parameters of the sequence used, in particular, the MT pulse shape, flip angle, duration, and offset frequency, and the repetition time TR' between successive MT pulses. Therefore, correction schemes will differ for different MTR sequences, and new data sets would be required to calculate these different correction schemes.

R. S. Samson C. A. Wheeler-Kingshott M. R. Symms D. J. Tozer P. S. Tofts 49938
2007-01-09Z 2018-05-23T16:26:26Z http://sro.sussex.ac.uk/id/eprint/674 This item is in the repository with the URL: http://sro.sussex.ac.uk/id/eprint/674 2007-01-09Z The quality of life of men with locally advanced prostate cancer during neoadjuvant hormone therapy: data from the Medical Research Council RT01 trial (ISRCTN 47772397)

OBJECTIVE To explore patients' quality of life (QoL) during neoadjuvant hormone therapy (HT) using data from the Medical Research Council RT01 trial of standard- (64 Gy/32-fraction) and high- (74 Gy/37-fraction) dose radiotherapy (RT, both given conformally). PATIENTS AND METHODS Of the 843 patients randomized to the RT01 trial, 316 completed the Functional Assessment Of Cancer Therapy core questionnaire with its additional prostate subscale, and the Short Form-36 Health Survey questionnaire with the University of California-Los Angeles Prostate Cancer Index before HT and again before starting RT. Three predefined QoL hypotheses were generated to focus the analyses. RESULTS For the three primary QoL analyses there was evidence that sexual functioning deteriorated, urinary function did not change, and there was a slight decline in physical well-being after >/= 3 months of HT. Sensitivity analyses confirmed these findings. Exploratory analyses also suggested that role functioning deteriorated, sleep was more disturbed, and there was an increase in fatigue. However, overall QoL was not reported to be affected and patients indicated an improvement in attitude and satisfaction with treatment. CONCLUSIONS In this group of men, many of whom reported reduced sexual functioning before treatment, the additional decline during HT seemed to be generally accepted as the price to pay for an appropriate cancer treatment. Nevertheless, these changes need to be discussed with patients before HT is commenced.

Richard J Stephens David P Dearnaley Richard Cowan Matthew Sydes Sharon Naylor Lesley Fallowfield 40578