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Harricharan S, Curran E, Lin HM, Walton L, Gurjar K, Nguyen K, Forsythe A. Real-world evidence in lung and hematologic oncology health technology appraisals: a review of six assessment agencies. Future Oncol 2023; 19:603-616. [PMID: 37083358 DOI: 10.2217/fon-2022-0553] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/22/2023] Open
Abstract
Aim: To assess the use and acceptability of real-world evidence (RWE) in lung and hematologic cancer appraisals. Materials & methods: A review of appraisals published by National Institute for Health and Care Excellence (NICE) in the UK was conducted. A total of 20 case studies employing RWE were identified and compared across five additional health technology assessment agencies: Scottish Medicines Consortium (SMC) (Scotland), CADTH (Canada), INESSS (Quebec), HAS (France) and IQWiG (Germany). Results: Of 80 RWE references from 20 case studies from NICE, 67 were identified in the respective CADTH submissions, 46 in IQWiG, 37 in INESSS, 37 in HAS, and 33 in SMC. NICE had the highest RWE acceptance rate (90%), followed by HAS (88%), SMC (82%), INESSS (73%), IQWiG (68%), and CADTH (67%). Conclusion: RWE was generally accepted by respective committees, allowing improved access to innovative treatments.
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Affiliation(s)
| | - Eileen Curran
- Takeda Development Center Americas, Inc, Lexington, MA 02421, USA
| | - Huamao Mark Lin
- Takeda Development Center Americas, Inc, Lexington, MA 02421, USA
| | - Laura Walton
- Takeda Pharmaceuticals, 8152, Zürich, Switzerland
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Kappas Mazzio A, Mendoza N, Lindsay Brown M, Sinha D, Messing J, Wilson S, Walton L. Yoga as a complementary approach to healing for adult victims and survivors of interpersonal violence. Complement Ther Clin Pract 2021; 44:101427. [PMID: 34246128 DOI: 10.1016/j.ctcp.2021.101427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 05/08/2021] [Accepted: 06/12/2021] [Indexed: 11/29/2022]
Abstract
PURPOSE Yoga is increasingly accepted to improve overall health and wellness and is considered a meaningful adjunct treatment for mental and physical health ailments associated with interpersonal violence (IV). This review provides background information about the use of yoga among individuals with IV histories and aims to inform researchers and practitioners about the available evidence on yoga's application and effectiveness. METHODS Using six databases, we systematically reviewed empirical literature examining yoga among IV survivors. Criteria for study inclusion: yoga included a physical component and was the primary intervention; participants had an IV history; peer-reviewed; and participants were 17 years and older. After review, 10 articles reporting findings from seven independent samples were included. FINDINGS Yoga demonstrated preliminary, positive implications as a complementary treatment for individuals with an IV history. Synthesizing across articles four themes emerged: (1) acceptability and feasibility, (2) enhancement of mental and physical health, (3) promotion of personal growth, and (4) facilitators and barriers to practice. CONCLUSIONS The nascent literature indicates potential benefits of integrating yoga into interventions for IV survivors to enhance physical and psychological functioning. The primary barriers to intervention were resources (e.g., access) and incompatibility with spiritual beliefs for select clients. Despite consistent barriers, preliminary findings indicate yoga has many positive implications for individuals with an IV history. Given the small evidence base and insufficient methodology, additional empirical research with diverse samples and sites, and robust designs, could improve the state of knowledge and strengthen the efficacy of this promising practice.
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Brook G, Church H, Evans C, Jenkinson N, McClean H, Mohammed H, Munro H, Nambia K, Saunders J, Walton L, Sullivan A. 2019 UK National Guideline for consultations requiring sexual history taking : Clinical Effectiveness Group British Association for Sexual Health and HIV. Int J STD AIDS 2020; 31:920-938. [PMID: 32718268 DOI: 10.1177/0956462420941708] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
This guideline is an update of a previous version published in 2013. In this new version, we have reflected changes in the way sexual health services are now provided by assuming an integrated Sexual Health/Sexual and Reproductive Healthcare service. There are new recommendations for online testing, female genital mutilation (FGM), chemsex and considerations for transgender (and non-binary) individuals. Previous versions rather assumed a cis-gender clientele and so we have taken a more mechanistic approach to sex and risk without assuming gender identification. We have updated our gender terminology in line with the British Association for Sexual Health and HIV 'sexual health standards for trans, including non-binary, people' although have retained the terminology of 'men' and 'women' in a few cases where it related to other guidelines, e.g. human papillomavirus vaccination and FGM.
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Affiliation(s)
- G Brook
- GUM/HIV, Central Middlesex Hospital, London, UK
| | - H Church
- GUM, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - C Evans
- 10 Hammersmith Broadway Sexual Health Clinic, London, UK
| | | | - H McClean
- GUM/HIV, Wilberforce Health Centre, City Health Care Partnership CIC, Hull, UK
| | - H Mohammed
- HIV and STI Department, National Infection Service, Public Health England, London, UK
| | - H Munro
- CSRH Hywel Dda HB, Wales, UK
| | - K Nambia
- Sexual Health & HIV Medicine, Brighton and Sussex University Hospitals NHS Trust, Brighton, UK
| | - J Saunders
- National Chlamydia Screening Programme, Public Health England, London, UK
| | - L Walton
- The Jefferiss Wing Centre for Sexual Health and HIV, Imperial College Healthcare NHS Trust, London, UK
| | - A Sullivan
- Chelsea and Westminster NHS Foundation Trust, London, UK
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Mufti A, Maliyar K, Walton L, Vender R, Yeung J. Guselkumab dosing interval optimization in adult patients with psoriasis: A retrospective, multicenter case series. J Am Acad Dermatol 2020; 83:1813-1814. [PMID: 32289394 DOI: 10.1016/j.jaad.2020.04.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 04/05/2020] [Accepted: 04/06/2020] [Indexed: 11/28/2022]
Affiliation(s)
| | - Khalad Maliyar
- Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Laura Walton
- Faculty of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Ronald Vender
- Department of Dermatology, McMaster University, Hamilton, Ontario, Canada
| | - Jensen Yeung
- Division of Dermatology, Toronto, Ontario, Canada; Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.
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Sims-Williams H, Rajapaksa K, Sinha S, Radatz M, Walton L, Yianni J, Newell-Price J. P45 Gamma knife radiosurgery for the primary management of acromegaly. J Neurol Neurosurg Psychiatry 2019. [DOI: 10.1136/jnnp-2019-abn.115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
ObjectivesReport outcome and morbidity data for the treatment of acromegaly with primary stereotactic radiosurgery (STRS).DesignRetrospective.Subjects20 patients with acromegaly who underwent primary STRS at the National Centre for Radiosurgery, Sheffield (UK) between 1985 and 2015.MethodsReview of notes, database, laboratory results, patient questionnaire and death certification. Guideline-based control was defined as normal age-sex-adjusted IGF1 levels and either random GH <1 µg/L or GH <0.3 µg/L (OGTT) or mean Growth Hormone Day Curve (GHDC) <1 µg/L.ResultsControl at 20 years was 100% and 75% on and off medication respectively. Median time to control on medication was 3 years and 7.4 years off medication. Median marginal radiation dose was 27.5 Gray and median follow-up was 167 months. Seven patients died, median age 65 years. There were no STRS-related deaths. 53% of patients developed new hypopituitarism at median follow-up of 146 months. First onset of hypopituitarism occurred up to 20 years after treatment. No other complications were noted. Three patients underwent trans-sphenoidal surgery due to poor biochemical control at a mean of 35 months.ConclusionsMorbidity from STRS is low. There is significant latency to biochemical control and new onset hypopituitarism. While primary surgical intervention remains the gold standard in acromegaly, primary STRS results should inform discussions with patients considering non-surgical management.
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Walton L. The panic triangle: onset of panic in scuba divers. Undersea Hyperb Med 2018; 45:505-509. [PMID: 30428239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Panic arising from physical or psychological stress is a common issue in reported incidents and accidents in scuba diving. Due to its effect on perception, thinking and diver behavior, the panic reaction is often a significant factor in the generation or escalation of problems, potentially leading to injuries and fatalities. The instinctive behaviors associated with panic are incompatible with the constraints of scuba diving (e.g., flight response to threat, leading to rapid ascent). Although the dangers are well known, the psychological mechanisms of panic and the implications for prevention/risk reduction are not sufficiently highlighted to recreational divers. In applied psychology, there are grounded theoretical models which describe the onset and maintenance of anxiety and panic, and an evidence base for approaches to anxiety management. For example, these models are used within structured psychological approaches for people experiencing anxiety disorders; and panic attacks are resolvable. Based on these models and underlying theory, this article proposes a new, accessible model for panic in divers. The potential uses of the model are to: (1) provide a simple framework for divers to understand the onset of panic; (2) promote the need for adequate training; (3) describe the importance of staying within training standards, qualifications and personal limitations; (4) support diver and dive educator understanding of individual factors in panic reactions (e.g. psychiatric conditions) placing greater emphasis on psychological fitness to dive; and (5) draw attention to approaches to improved regulation of emotion and promote individual responsibility.
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Lonski P, Walton L, Anderson N, Lydon J, Kron T, Chesson B, Prabhakar R. EP-1502: Dosimetric assessment of brass bolus using radiochromic film. Radiother Oncol 2017. [DOI: 10.1016/s0167-8140(17)31937-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Walton L, Marion G, Davidson RS, White PC, Smith LA, Gavier-Widen D, Yon L, Hannant D, Hutchings MR. The ecology of wildlife disease surveillance: demographic and prevalence fluctuations undermine surveillance. J Appl Ecol 2016. [DOI: 10.1111/1365-2664.12671] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Laura Walton
- Biomathematics and Statistics Scotland; James Clerk Maxwell Building The King's Buildings Peter Guthrie Tait Road Edinburgh EH9 3FD UK
- Disease Systems Team; SRUC, King's Buildings West Mains Road Edinburgh EH9 3JG UK
- Environment Department; Wentworth Way; University of York; York YO10 5NG UK
| | - Glenn Marion
- Biomathematics and Statistics Scotland; James Clerk Maxwell Building The King's Buildings Peter Guthrie Tait Road Edinburgh EH9 3FD UK
| | - Ross S. Davidson
- Disease Systems Team; SRUC, King's Buildings West Mains Road Edinburgh EH9 3JG UK
| | - Piran C.L. White
- Environment Department; Wentworth Way; University of York; York YO10 5NG UK
| | - Lesley A. Smith
- Disease Systems Team; SRUC, King's Buildings West Mains Road Edinburgh EH9 3JG UK
| | - Dolores Gavier-Widen
- Department of Biomedical Science and Veterinary Public Health; Swedish University of Agricultural Sciences; Box 7028 75007 Uppsala Sweden
| | - Lisa Yon
- School of Veterinary Medicine and Science; University of Nottingham; Sutton Bonington Campus Leicestershire LE12 5RD UK
| | - Duncan Hannant
- School of Veterinary Medicine and Science; University of Nottingham; Sutton Bonington Campus Leicestershire LE12 5RD UK
| | - Michael R. Hutchings
- Disease Systems Team; SRUC, King's Buildings West Mains Road Edinburgh EH9 3JG UK
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Abstract
Whether performed as a primary procedure or used to augment and support osseous reconstruction, tendon transfers are a key skill for the foot and ankle surgeon. Understanding the biomechanics preoperative and postoperatively is essential in performing appropriate procedures and in supporting patients through the rehabilitation process. Often the complexity of tendon transfer surgery is lost because it is deemed a soft tissue procedure and in theory should be less complex than osseous procedures. However, the dynamic nature of musculature and tendons require a deeper understanding of surgical and biomechanical concepts.
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Affiliation(s)
- Laura Walton
- Private Practice, 1890 LPGA Boulevard, Suite 230, Daytona Beach, FL 32117, USA
| | - Matthew F Villani
- Florida Hospital East Orlando Residency Training Program, 7727 Lake Underhill Road, Orlando, FL 32828, USA.
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Moreno PA, Garcia-Pacheco JL, Charvill J, Lofti A, Langensiepen C, Saunders A, Berckmans K, Gaspersic J, Walton L, Carmona M, Perez de la Camara S, Sanchez-de-Madariaga R, Pozo J, Muñoz A, Pascual M, Gomez EJ. iCarer: AAL for the Informal Carers of the Elderly. Stud Health Technol Inform 2015; 210:678-680. [PMID: 25991237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In the context of the long-term care for older adults, informal carers play a key role. Daily competing priorities or a care-skills deficit may lead them to stress, anxiety and/or depression. The iCarer project (AAL-2012-5-239) proposes the design and implementation of a cloud-inspired personalised and adaptive platform which will offer support to informal carers of older adults with cognitive impairment. By means of a holistic approach comprising technologies and services addressing the intelligent and interactive monitoring of activities, knowledge management for personalised guidance and orientation, virtual interaction, e-learning, care coordination facilities and social network services, iCarer aims to reduce the informal carer stress and to enhance the quality of care they provide, thus improving their quality of life. The iCarer platform will be evaluated through a multi-centre non-controlled study (4 months; 48 homes located in England and in Slovenia). Currently the iCarer project is completing the development work. The evaluation trial is expected to start in August 2015.
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Affiliation(s)
- P A Moreno
- Grupo de Bioingeniería y Telemedicina, ETSI de Telecomunicación, Universidad Politécnica de Madrid, Madrid, Spain
| | - J L Garcia-Pacheco
- Telemedicine and eHealth Unit, Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - J Charvill
- Tunstall Healthcare Group, Whitley, Yorkshire, U.K
| | - A Lofti
- School of Science and Technology, Nottingham Trent University, Nottingham, U.K
| | - C Langensiepen
- School of Science and Technology, Nottingham Trent University, Nottingham, U.K
| | | | | | - J Gaspersic
- Slovene Federation of Pensioners' Associations, Ljubljana, Slovenia
| | - L Walton
- Telecare Service, Nottingham City Council, Nottingham, U.K
| | - M Carmona
- Telemedicine and eHealth Unit, Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - S Perez de la Camara
- Telemedicine and eHealth Unit, Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | | | - J Pozo
- Telemedicine and eHealth Unit, Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - A Muñoz
- Telemedicine and eHealth Unit, Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - M Pascual
- Telemedicine and eHealth Unit, Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - E J Gomez
- Grupo de Bioingeniería y Telemedicina, ETSI de Telecomunicación, Universidad Politécnica de Madrid, Madrid, Spain
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Van Heugten CM, Walton L, Hentschel U. Can we forget the Mini-Mental State Examination? A systematic review of the validity of cognitive screening instruments within one month after stroke. Clin Rehabil 2014; 29:694-704. [PMID: 25381346 DOI: 10.1177/0269215514553012] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Accepted: 09/04/2014] [Indexed: 11/15/2022]
Abstract
Objective: To review systematically studies investigating the convergent, criterion, and predictive validity of multi-domain cognitive screening instruments in the first four weeks after stroke. Data sources: Electronic databases (Pubmed, PsycINFO, CINAHL, Embase) were searched until June 2014. Review methods: Studies concerning screening for cognitive dysfunction in stroke patients using multi-domain instruments, within four weeks postinfarct or haemorrhagic stroke, using tests taking no longer than one hour. Convergent, criterion, and predictive validity were examined. Results: A total of 51 studies investigating 16 cognitive screening instruments were identified. None of the instruments covered all of the most affected cognitive domains. Only one study investigated the convergent validity of a multi-domain test during the (sub)acute phase after stroke. A total of 15 studies examined the criterion validity of cognitive measurements during the acute phase after stroke. The Montreal Cognitive Assessment and Higher Cortical Function Deficit Test had good criterion validity. A total of 24 studies examined the predictive ability of multi-domain cognitive instruments applied in the acute phase after stroke. The Cognistat, Montreal Cognitive Assessment, and Functional Independence Measure-cognitive showed good predictive validity. The Mini-Mental State Examination is the most widely used cognitive screening instrument, but shows insufficient criterion validity. Conclusion: None of the existing instruments fulfils all criteria. The Montreal Cognitive Assessment is the best candidate at present, provided items measuring speed of information processing are added, and further studies investigating the optimal cut-offs are conducted.
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Affiliation(s)
- Caroline M Van Heugten
- Department Neuropsychology and Psychopharmacology, Maastricht University, Maastricht, The Netherlands
- School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - L Walton
- Department Neuropsychology and Psychopharmacology, Maastricht University, Maastricht, The Netherlands
| | - U Hentschel
- Department Neuropsychology and Psychopharmacology, Maastricht University, Maastricht, The Netherlands
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Walton L, Cousens R, Graf C. What IJCP authors think about open access: 392 IJCP authors explain their preferences. Int J Clin Pract 2013; 67:1211-2. [PMID: 24025035 DOI: 10.1111/ijcp.12282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
- L Walton
- International Journal of Clinical Practice, Wiley, Oxford, Oxon, UK.
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Throndson K, Davis V, Bohn W, Walton L, Bergner T. N022 The 2C ECG Project: Identifying Factors That Influence Nurses Confidence and Competence With ECG Monitoring. Can J Cardiol 2012. [DOI: 10.1016/j.cjca.2012.07.768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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Lagrange J, Benetos A, Walton L, Cruickshank K, Lacolley P, Regnault V. P3.04 INCREASED THROMBIN GENERATION AND VASCULAR REMODELING IN OBESE ZUCKER RATS. Artery Res 2012. [DOI: 10.1016/j.artres.2012.09.131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Owley T, Brune CW, Salt J, Walton L, Guter S, Ayuyao N, Gibbons RD, Leventhal BL, Cook EH. A pharmacogenetic study of escitalopram in autism spectrum disorders. Autism Res 2010; 3:1-7. [PMID: 20020537 DOI: 10.1002/aur.109] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE To determine the effect of serotonin transporter polymorphism promoter region (5-HTTPLR) genotypic variation (low, intermediate, and high expression groups) on response to escitalopram treatment of children and adolescents with autism spectrum disorders (ASDs). METHOD The study used a forced titration, open label design, with genotype blind until study completion. Participants were children and adolescents aged 4-17 years of age with a confirmed ASD (autistic disorder, Asperger's disorder, or pervasive developmental disorder, not otherwise specified). RESULTS There was an interaction between genotype group and time on the Aberrant Behavior Checklist (ABC) Irritability Subscale (primary outcome variable) (linear maximum marginal likelihood estimation=-4.84, Z=-2.89, SE=1.67, P=0.004). Examination of baseline to last visit revealed that a genotype grouping based on a previous study of platelet 5-HT uptake revealed less response in the genotype group that had S/S genotype for 5-HTTLPR and did not have a diplotype in intron 1 previously shown to be associated with increased platelet 5-HT uptake. CONCLUSION This genotype-blind, prospective pharmacogenetic study found the group of subjects with associated with the lowest platelet 5-HT uptake from previous study had the smallest reduction in ABC-Irritability scores after open label treatment with escitalopram. Replication is necessary to confirm these findings.
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Affiliation(s)
- Thomas Owley
- Department of Psychiatry, Institute for Juvenile Research, University of Illinois at Chicago, 1747 West Roosevelt Road, Chicago, IL 60608, USA
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Abstract
This is a systematic review of a consecutive series of 309 meningiomas treated with gamma knife stereotactic radiosurgery between 1994 and 2000. There was an extreme selection bias towards lesions unfavourable for surgery, determined by the patients referred for treatment: 70% of tumours involved the skull base, 47% specifically the cavernous sinus: 15% of patients had multiple meningiomatosis or type 2 neurofibromatosis. Tumour histology was the main determinant of growth control (p < 0.001), the 5-year actuarial control rates being 87% for typical meningiomas, 49% for atypical tumours and 0% for malignant lesions. Complications from radiosurgery were rare, occurring in 3% of tumours, and were most frequently trigeminal and eye movement disturbances treating cavernous sinus meningiomas. Given the problems inherent in managing these tumours, radiosurgery is a valuable strategy and adjuvant treatment for these meningiomas.
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Affiliation(s)
- Irfan Malik
- National Centre for Stereotactic Radiosurgery, Royal Hallamshire Hospital, Sheffield, UK
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Hancock PJB, Walton L, Mitchell G, Plenderleith Y, Phillips WA. Segregation by onset asynchrony. J Vis 2008; 8:21.1-21. [PMID: 19146254 DOI: 10.1167/8.7.21] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2007] [Accepted: 04/09/2008] [Indexed: 11/24/2022] Open
Abstract
We describe a simple psychophysical paradigm for studying figure-ground segregation by onset asynchrony. Two pseudorandom arrays of Gabor patches are displayed, to left and right of fixation. Within one array, a subset of elements form a figure, such as a randomly curving path, that can only be reliably detected when their onset is not synchronized with that of the background elements. Several findings are reported. First, for most participants, segregation required an onset asynchrony of 20-40 ms. Second, detection was no better when the figure was presented first, and thus by itself, than when the background elements were presented first, even though in the latter case the figure could not be detected in either of the two successive displays alone. Third, asynchrony segregated subsets of randomly oriented elements equally well. Fourth, asynchronous onsets aligned with the path could be discriminated from those lying on the path but not aligned with it. Fifth, both transient and sustained neural activity contribute to detection. We argue that these findings are compatible with neural signaling by synchronized rate codes. Finally, schizophrenic disorganization is associated with reduced sensitivity. Thus, in addition to bearing upon basic theoretical issues, this paradigm may have clinical utility.
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Abstract
Stereotactic Gamma Knife radiosurgery utilizes ionizing beams from (60)Co sources and relies on a combination of collimator sizes, weighting, etc to generate a high-dose region that is conformal with a designated target volume. Dose computation is typically performed by computer, but in this paper, single collimator dose profile behaviour is modelled analytically and then extended to accommodate multiple collimators of different weights with co-located isocentres. The dose profile from a single helmet is derived from a top-hat beam profile approximation and an idealized symmetric distribution of sources is used to represent the 201 sources within a collimating helmet. The results from the analysis are validated by an independent numerical model and also compared with those obtained by other groups using numerical and experimental methods. With respect to multiple collimators, the relationship between the size (full width half maximum) of the irradiated volume and relative collimator weighting is also examined using the simple analytical model. The simplicity of the mathematics clarifies the relationship between beam profile, dose profile and multiple collimator behaviour, and provides data that compare favourably with published literature.
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Affiliation(s)
- J Fenner
- Department of Medical Physics and Clinical Engineering, I Floor, Royal Hallamshire Hospital, Glossop Road, Sheffield, S10 2JF, UK.
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Affiliation(s)
- D Geggie
- A&E Department, Warrington General Hospital, Lovely Lane, Warrington, Cheshire WA13 OPS, UK.
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Owley T, Salt J, Guter S, Grieve A, Walton L, Ayuyao N, Leventhal BL, Cook EH. A prospective, open-label trial of memantine in the treatment of cognitive, behavioral, and memory dysfunction in pervasive developmental disorders. J Child Adolesc Psychopharmacol 2006; 16:517-24. [PMID: 17069541 DOI: 10.1089/cap.2006.16.517] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND This pilot study examined the effectiveness of memantine hydrochloride in improving cognitive functioning and behavioral symptoms in children with pervasive developmental disorders (PDDs). METHOD Subjects aged 3-12 years inclusive were enrolled in this 8-week, open-label study. Expressive and receptive language, nonverbal IQ, and nonverbal memory measures were administered at baseline and after 8 weeks of treatment with 0.4 mg/kg of memantine hydrochloride. Throughout the study, the Aberrant Behavior Checklist (ABC) was sent in weekly by parents as a measure of behavioral change. RESULTS Twelve of 14 subjects completed the study. Significant improvement from baseline was noted on the memory test (Children's Memory Scale Dot Learning Subtest). There were no significant differences from baseline on measures of expressive or receptive language or nonverbal IQ. There were significant improvements on a number of ABC subscales, including hyperactivity, lethargy, and irritability. There were no overall significant statistical differences from baseline on the Clinical Global Improvement-Severity (CGI-S) scale. On the Clinical Global Improvement-Improvement (CGI-I), 4 of 14 subjects showed minimal improvement, and none was deemed "much-improved" or "very much improved." CONCLUSIONS This small, prospective, open-label study suggests that memantine may be useful in the treatment of memory functioning and some behavioral symptoms in PDDs. The investigators did not see the same degree of change as endorsed by caretakers. Controlled studies are needed to substantiate and clarify these preliminary findings.
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Affiliation(s)
- Thomas Owley
- University of Illinois at Chicago, Department of Psychiatry, Institute for Juvenile Research, Chicago, Illinois 60608, USA.
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Nagaraja S, Lee KJ, Coley SC, Capener D, Walton L, Kemeny AA, Wilkinson ID, Griffiths PD. Stereotactic radiosurgery for brain arteriovenous malformations: quantitative MR assessment of nidal response at 1 year and angiographic factors predicting early obliteration. Neuroradiology 2006; 48:821-9. [PMID: 16944119 DOI: 10.1007/s00234-006-0131-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2005] [Accepted: 06/27/2006] [Indexed: 10/24/2022]
Abstract
INTRODUCTION We investigated the role of magnetic resonance angiography (MRA) in the early follow-up of patients after stereotactic radiosurgery (STRS) for cerebral arteriovenous malformations (AVMs) and determined the influence of individual morphological factors of AVMs in early response to treatment. METHODS A group of 40 patients (41 AVMs) consented to a dedicated 1.5-T MR protocol 12 months after receiving STRS for a brain AVM. In addition to standard spin echo sequences, 3-D contrast-enhanced sliding interleaved Ky MRA (CE-SLINKY) and dynamic time-resolved subtraction angiography (MR-DSA) were performed. Nidal volumes were calculated using CE-SLINKY data in patients with a persisting arteriovenous shunt. Planning angiographic data was investigated in all 40 patients. The following AVM factors were used in the statistical analysis to determine their role in nidus obliteration: (1) maximum linear dimension, (2) nidal volume, (3) AVM location (4) nidal morphology, (5) venous drainage, (6) "high-flow angiographic change", (7) prior embolization, and (8) dose reduction. RESULTS Complete nidal obliteration was found in 9 patients, 26 showed greater than 50% nidal reduction and 6 had less than 50%. Two AVM factors, venous drainage and AVM location, were found to significantly correlate with rate of obliteration. CONCLUSION We successfully demonstrated the use of MRA to quantitatively assess the response of AVMs to STRS. Two AVM factors, venous drainage and AVM location were found to correlate with rate of obliteration prior to the application of the Bonferroni correction, but if this more rigorous statistical test was applied then none of the factors was found to be significant.
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Affiliation(s)
- S Nagaraja
- Section of Academic Radiology, University of Sheffield, Royal Hallamshire Hospital, Glossop Road, Sheffield, S10 2JF, England, UK.
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Rowe J, Walton L, Radatz M, Kemeny A. Use of Gamma-Knife Stereotactic Radiosurgery in the Management of Cavernous Sinus Meningiomas. Skull Base 2005. [DOI: 10.1055/s-2005-916479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Rajaraman C, Rowe JG, Walton L, Malik I, Radatz M, Kemeny AA. Treatment options for von Hippel-Lindau's haemangioblastomatosis: the role of gamma knife stereotactic radiosurgery. Br J Neurosurg 2005; 18:338-42. [PMID: 15702831 DOI: 10.1080/02688690400004944] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Haemangioblastomas secondary to von Hippel-Lindau (VHL) disease can be difficult to manage surgically, which has lead to an interest in the use of stereotactic radiosurgery. Retrospectively reviewed here are 30 tumours treated in 14 patients with a mean +/- SD follow-up of 34 +/- 24 months. During this time, three of the 14 patients (21%) died, two of generalized progressive disease. Before radiosurgery, the median time between interventions for cranial haemangioblastomas was 3 years (mean 3.9 +/- 5.0 years). After radiosurgery, the tendency for cranial disease progression was similar, 50% of patients developing further disease by 5 years. Local tumour control was achieved in the majority of cases and estimates of this are included. Radiosurgery is a useful palliative measure controlling the majority of haemangioblastomas, although its efficacy in these patients is limited by the tendency of further disease to develop or progress intracranially.
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Affiliation(s)
- C Rajaraman
- National Centre for Stereotactic Radiosurgery, Royal Hallamshire Hospital, Sheffield, UK
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Abstract
OBJECTIVE To assess the effect of escitalopram in the treatment of pervasive developmental disorders (PDDs). METHOD This 10-week study had a forced titration, open-label design. Twenty-eight subjects (mean age 125.1 +/- 33.5 months) with a PDD received escitalopram at a dose that increased weekly to a maximum dose of 20 mg as tolerated. The Aberrant Behavior Checklist-Community Version (ABC-CV) and the Clinical Global Impression scale (CGI) were used to assess outcome. RESULTS There was significant improvement in ABC-CV Irritability Subscale Scores (baseline mean 20.5 +/- 5.9 to final mean 10.9 +/- 7.2; p < or = .001) and in the other ABC-CV Subscales. Improvement on Clinical Global Improvement Scale severity rating was also significant (baseline mean 5.2 +/- 1.0 to final mean 4.6 +/- 1.2; p < or = .001). Twenty-five percent of the subjects responded at a dose less than 10 mg and did not tolerate the 10-mg dose, and an additional 36% responded at a dose greater than or equal to 10 mg. Final dose was unrelated to weight and only weakly correlated with age. CONCLUSIONS This open-label study found escitalopram to be useful in treating some difficulties common in PDDs. A wide variability in dose was found that could not be accounted for by weight and only partially by age. The study provides information useful for the design of double-blind, placebo-controlled studies of escitalopram in PDDs.
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Affiliation(s)
- Thomas Owley
- Department of Psychiatry, University of Chicago MC 3077, 5841 South Maryland Avenue, Chicago, IL 60637, USA.
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Fenner JW, Mehrem RA, Ganesan V, Riley S, Middleton SE, Potter K, Walton L. Radiosurgery planning supported by the GEMSS grid. Stud Health Technol Inform 2005; 112:190-7. [PMID: 15923728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
GEMSS (Grid Enabled Medical Simulation Services IST-2001-37153) is an EU project funded to provide a test bed for Grid-enabled health applications. Its purpose is evaluation of Grid computing in the health sector. The health context imposes particular constraints on Grid infrastructure design, and it is this that has driven the feature set of the middleware. In addition to security, the time critical nature of health applications is accommodated by a Quality of Service component, and support for a well defined business model is also included. This paper documents experience of a GEMSS compliant radiosurgery application running within the Medical Physics department at the Royal Hallamshire Hospital in the UK. An outline of the Grid-enabled RAPT radiosurgery application is presented and preliminary experience of its use in the hospital environment is reported. The performance of the software is compared against GammaPlan (an industry standard) and advantages/disadvantages are highlighted. The RAPT software relies on features of the GEMSS middleware that are integral to the success of this application, and together they provide a glimpse of an enabling technology that can impact upon patient management in the 21st century.
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Affiliation(s)
- J W Fenner
- Department of Medical Physics, University of Sheffield, I Floor, Royal Hallamshire Hospital, Glossop Road, Sheffield, UK
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Abstract
Since its introduction, gamma knife radiosurgery has become an important treatment modality for cerebral arteriovenous malformations. This paper is a brief overview of the technique used, of the clinical results achieved and of the experience gained in Sheffield.
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Affiliation(s)
- A A Kemeny
- National Centre for Stereotactic Radiosurgery, Royal Hallamshire Hospital, Sheffield, UK.
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28
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Abstract
OBJECTIVE To evaluate the clinical results achievable using current techniques of gamma knife stereotactic radiosurgery to treat sporadic unilateral acoustic neuromas. METHODS A retrospective review of 234 consecutive patients treated for unilateral acoustic neuromas between 1996 and 1999, with a mean (SD) follow up of 35 (16) months. Tumour control was assessed with serial radiological imaging and by the need for surgical intervention. Hearing preservation was assessed using Gardner-Robertson grades. Details of complications including cranial neuropathies and non-specific vestibulo-cochlear symptoms are included. RESULTS A tumour control rate in excess of 92% was achieved, with only 3% of patients undergoing surgery after radiosurgery. Results were less good for larger tumours, but control rates of 75% were achieved for 35-45 mm diameter lesions. Of patients with discernible hearing, Gardner-Robertson grades were unchanged in 75%. Facial nerve function was adversely affected in 4.5%, but fewer than 1% of patients had persistent weakness. Trigeminal symptoms improved in 3%, but developed in 5% of patients, being persistent in less than 1.5%. Transient non-specific vestibulo-cochlear symptoms were reported by 13% of patients. CONCLUSIONS Tumour control rates, while difficult to define, are comparable after radiosurgery with those experienced after surgery. The complications and morbidity after radiosurgery are far less frequent than those encountered after surgery. This, combined with its minimally invasive nature, may make radiosurgery increasingly the treatment of choice for small and medium sized acoustic neuromas.
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Affiliation(s)
- J G Rowe
- Department of Stereotactic Radiosurgery, Royal Hallamshire Hospital, Sheffield, UK.
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Rowe JG, Radatz MWR, Walton L, Soanes T, Rodgers J, Kemeny AA. Clinical experience with gamma knife stereotactic radiosurgery in the management of vestibular schwannomas secondary to type 2 neurofibromatosis. J Neurol Neurosurg Psychiatry 2003; 74:1288-93. [PMID: 12933938 PMCID: PMC1738689 DOI: 10.1136/jnnp.74.9.1288] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVE To evaluate the results of stereotactic radiosurgery treating vestibular schwannomas secondary to type 2 neurofibromatosis. METHODS A retrospective review of 122 type 2 neurofibromatosis vestibular schwannomas consecutively treated in 96 patients. Tumour control was assessed by recourse to surgical intervention, by serial radiological imaging, and by the calculation of relative growth ratios in patients (n=29) habouring untreated contralateral tumours to act as internal controls. Hearing function was assessed with Gardner-Robertson grades and with averaged pure tone audiogram thresholds. Other complications are detailed. RESULTS Applying current techniques, eight years after radiosurgery it was estimated that 20% of patients will have undergone surgery for their tumour, 50% will have radiologically controlled tumours, and in 30% there will be some variable concern about tumour control, but up to that time they will have been managed conservatively. Relative growth ratios one and two years after treatment indicate that radiosurgery confers a significant (p=0.01) advantage over the natural history of the disease. Analysis of these ratios beyond two years was precluded by the need to intervene and radiosurgically treat the contralateral control tumours in more than 50% of the cases. This growth control was achieved with 40% of patients retaining their Gardner-Robertson hearing grades three years after treatment, (40% having some deterioration in grade, 20% becoming deaf). Pure tone audiogram results suggest some progressive long term hearing loss, although interpretation of this is difficult. Facial and trigeminal neuropathy occurred in 5% and 2%. CONCLUSIONS Radiosurgery is a valuable minimally invasive alternative treatment for these tumours. For most patients, it controls growth or defers the need for surgery, or both. There is a price in terms of hearing function, although this may compare favourably with the deafness associated with the natural history of the disease, and with surgery. In deciding on therapy, patients should be aware of this treatment option.
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Affiliation(s)
- J G Rowe
- National Centre for Stereotactic Radiosurgery, Royal Hallamshire Hospital, Sheffield, UK.
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Abstract
Recognizing a change in our workload and variabilities in referral patterns, we reviewed our previous activity from 1994 to 2000 retrospectively and examined prospectively formal referrals to the Unit in 2001. Arteriovenous malformations still constitute 30% of referrals and treatments, although as a proportion of our workload, this has declined. Radiosurgery is increasingly being chosen as a first line treatment for small and moderate-sized acoustic neuromas, although referral rates vary widely, some neuroscience units referring all and others none of their acoustic neuromas at least for a radiosurgical opinion. About 100 meningiomas, mainly skull-base and/or recurrent tumours after previous surgery, are now treated per year. Compared with other units world-wide, very few pituitary adenomas and cerebral metastases are treated. The implications of this are discussed.
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Affiliation(s)
- J G Rowe
- National Centre for Stereotactic Radiosurgery, Royal Hallamshire Hospital, Sheffield, UK
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Bari ME, Forster DMC, Kemeny AA, Walton L, Hardy D, Anderson JR. Malignancy in a vestibular schwannoma. Report of a case with central neurofibromatosis, treated by both stereotactic radiosurgery and surgical excision, with a review of the literature. Br J Neurosurg 2002; 16:284-9. [PMID: 12201399 DOI: 10.1080/02688690220148888] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Malignant change in schwannoma is rare. Malignant change in a vestibular schwannoma (acoustic neuroma) is even more rare. This paper presents a case of rapidly growing vestibular schwannoma first treated by radiosurgery whose histopathology after surgical excision 42 months later showed malignant changes. Up to now, eight cases of malignancy in eighth nerve tumours have been reported, four of which, including the present case, had previously been treated with radiosurgery and four cases that had not received radiation. Thus, it would seem, the overall incidence is extremely low. Nevertheless, extreme vigilance and careful reporting continues to be necessary.
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Affiliation(s)
- M E Bari
- Department of Neurosurgery, Royal Hallamshire Hospital, Sheffield, UK
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Abstract
In 1999, Northwestern University's Galter Health Sciences Library redesigned the library orientation program for first-year medical students. Surveys indicated tours were ineffective and students retained little of the information presented. Furthermore, the tour was not related to the student's curriculum and did not reinforce their learning objectives. As a replacement, the library staff developed a self-directed two-hour library open house. Stations throughout the library showcased the library staff, services, and resources, focusing on the first-year student curriculum. A follow-up survey found this redesign more useful and relevant to the students' course work, indicating libraries should be creating more interactive tours for students allowing them to learn actively.
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Affiliation(s)
- L Walton
- Galter Health Sciences Library, Northwestern University, 303 East Chicago Avenue, Chicago, IL 60611, USA
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Warren DJ, Hoggard N, Walton L, Radatz MW, Kemeny AA, Forster DM, Wilkinson ID, Griffiths PD. Cerebral arteriovenous malformations: comparison of novel magnetic resonance angiographic techniques and conventional catheter angiography. Neurosurgery 2001; 48:973-82; discussion 982-3. [PMID: 11334299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
OBJECTIVE To investigate the potential of novel magnetic resonance (MR) angiographic techniques for the assessment of cerebral arteriovenous malformations. METHODS Forty patients who were about to undergo stereotactic radiosurgery were prospectively recruited. Three-dimensional, sliding-slab interleaved ky (SLINKY), time-of-flight acquisition was performed, as was a dynamic MR digital subtraction angiography (DSA) procedure in which single thick slices (6-10 cm) were obtained using a radiofrequency spoiled Fourier-acquired steady-state sequence (1 image/s). Sixty images were acquired, in two or three projections, during passage of a 6- to 10-ml bolus of gadolinium chelate. Subtraction and postprocessing were performed, and images were viewed in an inverted cine mode. SLINKY time-of-flight acquisition was repeated after the administration of gadolinium. Routine stereotactic conventional catheter angiography was performed after MR imaging. All images were assessed (in a blinded randomized manner) for Spetzler-Martin grading and determination of associated vascular pathological features. RESULTS Forty-one arteriovenous malformations were assessed in 40 patients. Contrast-enhanced (CE) SLINKY MR angiography was the most consistent MR imaging technique, yielding a 95% correlation with the Spetzler-Martin classification defined by conventional catheter angiography; MR DSA exhibited 90% agreement, and SLINKY MR angiography exhibited 81% agreement. CE SLINKY MR angiography provided improved nidus delineation, compared with non-CE SLINKY MR angiography. Dynamic information from MR DSA significantly improved the observation of early-draining veins and associated aneurysms. CONCLUSION CE SLINKY MR angiographic assessment of cerebral arteriovenous malformations offers significant advantages, compared with the use of non-CE SLINKY MR angiography, including improved nidus demonstration. MR DSA shows promise as a noninvasive method for dynamic angiography but is presently restricted by limitations in both temporal and spatial resolution.
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Affiliation(s)
- D J Warren
- Section of Academic Radiology, University of Sheffield, England
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Braly P, Sedlacek T, Kinney W, Sheets EE, Walton L, Farber F, Cox JT. Reporting the Potential Benefits of New Technologies for Cervical Cancer Screening. J Low Genit Tract Dis 2001; 5:73-81. [PMID: 17043579 DOI: 10.1046/j.1526-0976.2001.005002073.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The AHCPR released its evidence-based report, "Evaluation of Cervical Cytology" in early 1999. This report represents the most comprehensive analysis available to date of Pap smears and new technologies designed to improve cervical cancer screening. Both the ACOG and the AHCPR have released simplified summaries of the results of the evidence report that may lead to misunderstandings of the potential clinical impact of these new technologies. This report reviews the 4 major statements in these summaries and discusses how they are either incorrect based on the full AHCPR report or may be misinterpreted because their ramifications are not fully discussed. New screening technology has the potential to finally bring the sensitivity of a new Pap test to an acceptable level. The increased sensitivity afforded by these new technologies can reduce negative outcomes at reasonable cost-effectiveness ratios and at an equivalent or superior specificity compared to the conventional Pap smear.
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Affiliation(s)
- P Braly
- Department of Obstetrics and Gynecology, Louisiana State University Medical Center, New Orleans, LA, USA
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Tozer-Loft SM, Walton L, Forster DM, Kemeny AA. An improved technique for comparing Gamma Knife dose-volume distributions in stereotactic radiosurgery. Phys Med Biol 1999; 44:1905-19. [PMID: 10473204 DOI: 10.1088/0031-9155/44/8/305] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A function derived from the geometry of brachytherapy dose distributions is applied to stereotactic radiosurgery and an algorithm for the production of a novel dose-volume histogram, the Anderson inverse-square shifted dose-volume histogram (DVH), is proposed. The expected form of the function to be plotted is checked by calculating its value for single focus exposures, and its application to clinical examples of Gamma Knife treatments described. The technique is shown to provide a valuable tool for assessing the adequacy of radiosurgical plans and comparing and reporting dose distributions.
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Affiliation(s)
- S M Tozer-Loft
- Department of Medical Physics, Weston Park Hospital, Sheffield, UK.
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Mackerras D, Irwig L, Simpson JM, Weisberg E, Cardona M, Webster F, Walton L, Ghersi D. Randomized double-blind trial of beta-carotene and vitamin C in women with minor cervical abnormalities. Br J Cancer 1999; 79:1448-53. [PMID: 10188889 PMCID: PMC2362702 DOI: 10.1038/sj.bjc.6690231] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
A double-blind, placebo-controlled, randomized, factorial study using a daily oral administration of 30 mg beta-carotene and/or 500 mg vitamin C was conducted in 141 women with colposcopically and histologically confirmed minor squamous atypia or cervical intra-epithelial neoplasia (CIN) I. Over approximately 2 years of follow-up, 43 lesions regressed to normal and 13 progressed to CIN II. The regression rate was slightly higher, but not significantly so, in those randomized to beta-carotene compared to no beta-carotene (hazard ratio = 1.58, 95% CI: 0.86-2.93, P = 0.14) and slightly lower, but not statistically significant, for those randomized to vitamin C compared to no vitamin C (hazard ratio = 0.65, 95% CI: 0.35-1.21, P = 0.17). In a model with no interaction, the progression rate was slightly higher in those randomized to beta-carotene (hazard ratio = 1.75, 95% CI: 0.57-5.36, P = 0.32) and also in those randomized to vitamin C (hazard ratio = 2.40, 95% CI: 0.74-7.80, P = 0.13). Neither of these were statistically significant. However, there was some evidence of an interaction effect of the two compounds on the progression rate (P = 0.052), with seven of the progressed lesions occurring in those randomized to both vitamins compared to a total of six in the three other groups. The currently available evidence from this and other trials suggests that high doses of these compounds are unlikely to increase the regression or decrease the progression of minor atypia and CIN I.
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Affiliation(s)
- D Mackerras
- Department of Public Health and Community Medicine, University of Sydney, NSW, Australia
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37
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Affiliation(s)
- A P Heaney
- Department of Endocrinology, Central Manchester Healthcare Trust, UK
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Modesitt SC, Waters AB, Walton L, Fowler WC, Van Le L. Vulvar intraepithelial neoplasia III: occult cancer and the impact of margin status on recurrence. Obstet Gynecol 1998; 92:962-6. [PMID: 9840558 DOI: 10.1016/s0029-7844(98)00350-0] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
OBJECTIVE To determine the impact of margin status on disease recurrence and the incidence of occult cancer in women diagnosed with vulvar intraepithelial neoplasia (VIN) III and treated with surgical excision. METHODS Between 1989 and 1995, 73 women were diagnosed preoperatively with VIN III by vulvar biopsy and were treated with surgical resection. Patients were examined postoperatively, and recurrence was diagnosed when a biopsy of suspicious lesions confirmed VIN III. RESULTS The mean age was 45 years; 81% of the patients were white, and 18% were black. Eighty-two percent of the women had used tobacco, 56% had prior cervical dysplasia, and 37% had prior genital warts. An underlying squamous vulvar cancer was found in 22% of patients at initial treatment for VIN III. Fifty-nine women had follow-up of at least 7 months. Of these, 66% (39 of 59) had positive surgical margins, 31% (18 of 59) had negative margins and 3% had unknown margins (two of 59). With positive margins, 46% (18 of 39) suffered recurrent disease; with negative margins, only 17% (three of 18) had recurrent disease (P = .03). Multifocal disease and a history of genital warts also correlated with VIN III recurrence (P = .03 for both). CONCLUSION A significant number of women diagnosed initially with VIN III on a vulvar biopsy harbored occult vulvar cancer. Recurrences were almost threefold higher when margins were positive for residual VIN III. We conclude that surgical resection is an appropriate method of treatment of VIN III for both diagnostic and therapeutic purposes.
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Affiliation(s)
- S C Modesitt
- Department of Obstetrics and Gynecology, University of North Carolina, Chapel Hill 27599-7570, USA
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Abstract
AIMS This study investigated whether child abuse (CSA) was associated with earlier substance use and greater severity of substance dependence and what aspects of CSA might predict substance abuse. DESIGN The study compared (a) drug and alcohol treatment clients with and without a history of CSA and (b) CSA survivors outside drug and alcohol treatment who did or did not have current substance abuse. SETTINGS Semi-structured interviews took place at participants' homes, treatment agencies or the research centre. PARTICIPANTS Volunteer participants included 100 women recruited from drug and alcohol treatment programmes and 80 CSA survivors recruited through CSA counseling services and medial advertising. MEASUREMENTS The results focus on data from the Opiate Treatment Index, Severity of Alcohol Dependence Questionnaire, Substance Dependence Scale, Self-Esteem Inventory and self-reported histories of CSA. FINDINGS There were no differences between CSA survivors and other drug and alcohol treatment clients in their severity of dependence. Women with a history of CSA more frequently identified stimulants as their main problem drug and reported an earlier age of first intoxication and earlier use of inhalants. Among abused CSA survivors outside drug and alcohol treatment, women with current substance abuse had typically been abused during adolescence by someone outside the family, whereas those without current substance abuse were typically abused by family members before adolescence. CONCLUSIONS The results suggest that adolescence is a crucial time for the influence of CSA experiences on substance abuse.
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Affiliation(s)
- T J Jarvis
- National Drug and Alcohol Research Centre, University of New South Wales, Australia
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40
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Akhtar K, Kamalky-asl ID, Lamb WR, Laing I, Walton L, Pearson RC, Parrott NR. Metabolic and inflammatory responses after laparoscopic and open inguinal hernia repair. Ann R Coll Surg Engl 1998; 80:125-30. [PMID: 9623379 PMCID: PMC2503002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
A prospective comparison of metabolic and inflammatory responses after laparoscopic and open inguinal hernia operations was undertaken. There were 10 patients in each group. Plasma levels of cortisol, growth hormone, prolactin, C-reactive protein (CRP) and interleukin-6 (IL-6) were measured preoperatively and at fixed intervals up to 120 h postoperatively. In vitro, endotoxin stimulated whole blood tumour necrosis factor alpha (TNF alpha) was measured in preoperative and 24 h postoperative blood samples. Changes in the plasma levels of cortisol, growth hormone and prolactin showed no statistically significant difference between the groups. No significant change in IL-6 levels were recorded in any group. Changes in CRP levels were significantly higher (P < 0.006) in open hernia patients. Endotoxin stimulated TNF alpha production was suppressed in both groups. The degree of suppression in open hernia patients was significantly higher (P < 0.005). This study has shown that both these operations produce similar stress responses. However, open hernia operation results in a higher acute phase response and induces a greater endotoxin tolerance.
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Affiliation(s)
- K Akhtar
- University Department of Surgery, Manchester Royal Infirmary
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41
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Walton L, Hampshire A, Forster DM, Kemeny AA. Stereotactic localization with magnetic resonance imaging: a phantom study to compare the accuracy obtained using two-dimensional and three-dimensional data acquisitions. Neurosurgery 1997; 41:131-7; discussion 137-9. [PMID: 9218305 DOI: 10.1097/00006123-199707000-00027] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
OBJECTIVE To compare the accuracy of stereotactic localization using magnetic resonance imaging (Siemens 1.5-T Magnetom; Siemens, Erlangen, Germany) with two-dimensional and three-dimensional data acquisition techniques. METHODS A phantom study was performed in which the coordinates of an array of rods were determined from images in both two-dimensional and three-dimensional studies and compared with measured values in a series of transverse, coronal, and sagittal images. RESULTS The results demonstrated a distinct advantage in using three-dimensional acquisition; an error greater than 2 mm was identified in only 0.8% of the imaged volume, compared with 12% of the imaged volume in the two-dimensional study. CONCLUSION The results indicated that more accurate stereotactic localization is achieved with a three-dimensional acquisition.
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Affiliation(s)
- L Walton
- Department of Medical Physics and Clinical Engineering, Weston Park Hospital, Sheffield, England
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Schwartz M, Sixel K, Young C, Kemeny A, Forster D, Walton L, Franssen E. Prediction of obliteration of arteriovenous malformations after radiosurgery: the obliteration prediction index. Can J Neurol Sci 1997; 24:106-9. [PMID: 9164685 DOI: 10.1017/s0317167100021417] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE To describe the response to single dose photon stereotactic radiosurgery of arteriovenous malformations (AVMs) so that the probability of success or failure of treatment may be predicted for the individual patient. METHOD The obliteration prediction index (OPI) was calculated for AVMs by dividing the marginal dose of radiation in Gray (Gy) by the lesion diameter in centimetres in cohorts of 42 patients treated with the modified linear accelerator at Toronto-Sunnybrook Regional Cancer Centre and 394 patients treated with the gamma unit at the Royal Hallamshire Hospital, Sheffield, United Kingdom. Patients were grouped into ranges by OPI and the proportion of success and failure was calculated for each group. An exponential function [P = 1-A.e(-B.OPI)] was fitted to the data by the least squares method. RESULTS Despite systematic differences in radiation treatment, that is, marginal doses of 15 and 20 Gy in Toronto and most Sheffield patients with a marginal dose of 25 Gy, the resultant data points exhibited similar behaviour. CONCLUSION The function [P = 1-A.e(-B.OPI)] partly describes the biological effect of radiation and is independent of the radiation device used. Radiosurgery centres can use this model to facilitate predictions of successful treatment for individual patients.
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Affiliation(s)
- M Schwartz
- Sunnybrook Health Science Centre, Toronto, Ontario, Canada
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Rennie I, Forster D, Kemeny A, Walton L, Kunkler I. The use of single fraction Leksell stereotactic radiosurgery in the treatment of uveal melanoma. Acta Ophthalmol Scand 1996; 74:558-62. [PMID: 9017041 DOI: 10.1111/j.1600-0420.1996.tb00734.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Fourteen patients with posterior uveal melanomas were treated using single fraction stereotactic radiosurgery. In each case a dose of 70 Gy was administered to the periphery of the tumour. Regression of the tumour has been observed in 13 patients, whilst the lesion has remained unchanged in one patient. The visual acuity has deteriorated in all 14 patients. Significant radiation induced adverse reactions were noted in 13 patients and include; retinopathy, optic neuropathy, rubeosis iridis, and secondary glaucoma. Two patients have required enucleation because of intractable rubeotic glaucoma. One patient has died from proven metastases. Although stereotactic radiosurgery appears to be a practical and effective method of treating uveal melanomas, its usefulness is limited by a high incidence of radiation induced adverse reactions. Further work is required to refine the current treatment protocol and establish an optimal prescription dose.
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Affiliation(s)
- I Rennie
- Department of Ophthalmology and Orthoptics, University of Sheffield, UK
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Swain SM, Rowland J, Weinfurt K, Berg C, Lippman ME, Walton L, Egan E, King D, Spertus I, Honig SF. Intensive outpatient adjuvant therapy for breast cancer: results of dose escalation and quality of life. J Clin Oncol 1996; 14:1565-72. [PMID: 8622073 DOI: 10.1200/jco.1996.14.5.1565] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
PURPOSE A dose-escalation study was conducted to determine the maximum-tolerated dose (MTD) and dose-limiting toxicities (DLTs) of cyclophosphamide (CY) in combination with granulocyte colony-stimulating factor (G-CSF0 and doxorubicin (DOX) given every 2 weeks for eight cycles as outpatient adjuvant therapy for node-positive breast cancer. A pilot study to assess quality of life (QOL) was performed. PATIENTS AND METHODS From March 1991 to April 1993, 19 patients were entered. Patients received escalating doses of CY intravenously (i.v.) (1,000 mg/m2, 1,500 mg/m2, 2,000 mg/m2, or 2,500 mg/m2) with DOX 40 mg/m2, G-CSF 10 micrograms/kg/d on days 2 to 12, and mesna, every 2 weeks for eight cycles. QOL was measured by the Profile of Mood States (POMS), the Psychosocial Adjustment to Illness Scale-Self Report (PAIS-SR), and a 27-item QOL scale. RESULTS The CY dose of 2,500 mg/m2 every 2 weeks elicited toxicities that required dose reductions secondary to a combination of thrombocytopenia, hematuria, and anemia that required transfusion. The dose of 2,000 mg/m2 resulted in an acceptable toxicity profile. Ninety-two percent of cycles at the 2,000-mg/m2 dose were delivered on schedule and 77% without hospitalization. QOL assessments indicated high levels of distress measured by POMS in 47%, poor overall quality of life in 40%, and significant problems with physical symptoms in less than 27% of all patients for any given cycle. CONCLUSION A dose of CY at 2,000 mg/m2 can be administered every 2 weeks with DOX and G-CSF for eight cycles in the outpatient setting with manageable toxicity. The majority of women described levels of physical symptoms and emotional distress as tolerable during treatment.
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Affiliation(s)
- S M Swain
- Vincent T. Lombardi Cancer Center, Georgetown University Medical Center, Washington, DC, USA
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Forster DM, Kemeny AA, Pathak A, Walton L. Radiosurgery: a minimally interventional alternative to microsurgery in the management of acoustic neuroma. Br J Neurosurg 1996; 10:169-74. [PMID: 8861308 DOI: 10.1080/02688699650040322] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We report the results of treatment with radiosurgery of 29 tumours in 27 patients with acoustic neuromas between 1986 and 1989. The median follow-up was 6.6 years. The treatment appears to be an effective alternative to surgery for patients with tumours of 3 cm diameter or less. The mortality and morbidity of the treatment and the presentation of cranial nerve function is comparable to the very best surgical results. Every patient with an acoustic neuroma should be informed about this alternative to direct surgery.
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Olukoga AO, Mitchell R, Walton L, Robertson WR, Laing I. Differences in serum luteinizing hormone measurements by immunoradiometric assay induced by kinetic manipulation of assay conditions are dependent on the endocrine milieu of serum. Ann Clin Biochem 1996; 33 ( Pt 2):107-11. [PMID: 8729717 DOI: 10.1177/000456329603300202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Divergent estimates for luteinizing hormone (LH) in individual serum samples may be given by different immunoassays. In order to investigate this phenomenom further, we have studied the effect of differences in assay kinetics within the same immunoradiometric assay (IRMA) configuration on LH measurement in sera from different endocrine states. Three pairs of monoclonal/polyclonal two-site IRMA systems for LH were developed from three LH monoclonal antibodies and a common polyclonal anti-human chorionic gonadotrophin. For IRMA systems a short and long assay, which were different only with respect to the incubation time (1/2 h and overnight respectively), of the labelled monoclonal first antibody were performed. The IRMAs were all standardized against the LH international reference preparation 68/40. LH concentrations were measured by all the IRMAs in sera obtained from normal men (n = 11) and from women with polycystic ovarian syndrome (PCO; n = 13). In normal men, there were no differences in LH estimates between the short and the long assays of the three IRMA systems, and the ratios of long to short assays were similar for all the systems. However, in PCO there were significant differences between short and long assays and the ratios of long to short assays were different for the IRMA systems. These results indicate that kinetic differences between IRMAs of the same antibody configuration can be associated with differences in measured LH concentrations, depending on the endocrine status of the sera studied. As LH glycoform patterns are known to differ between normal men and PCO, the observed changes in LH estimates may be due to the different glycoform composition.
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Affiliation(s)
- A O Olukoga
- Department of Clinical Biochemistry, Manchester Royal Infirmary, Salford, UK
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Ohles JA, Walton L. The Internet: a valuable resource for the hospital librarian. Bull Med Libr Assoc 1996; 84:110-1. [PMID: 8938340 PMCID: PMC226135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- J A Ohles
- University of Connecticut Health Center, Farmington 06030-5370, USA
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Walton L, Hampshire A, Forster DM, Kemeny AA. Accuracy of stereotactic localisation using magnetic resonance imaging: a comparison between two- and three-dimensional studies. Stereotact Funct Neurosurg 1996; 66 Suppl 1:49-56. [PMID: 9032844 DOI: 10.1159/000099700] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The accuracy of stereotactic localisation using magnetic resonance (MR) imaging has been assessed in a phantom study. Parallel studies compared the accuracy obtained. First, a series of two-dimensional (2D) MR slices (transverse, coronal, and sagittal) was acquired sequentially to image the three-dimensional (3D) volume of the phantom. Then, the same volume was imaged in a 3D MR study in which the entire volume was excited simultaneously and 2D slices in transverse, coronal, and sagittal planes were then reconstructed from the 3D data set. The results showed that the 3D acquisition gave superior results in all three planes, and overall it was found that only 1% of the phantom volume was affected by an error greater than 2 mm, compared with 11% for the 2D study. New facilities for image quality assurance provided in GammaPlan version 3.0 have been tested against images from the 2D study with known distortion and consequent localisation errors and successfully identified all images in which the localisation errors were likely to be greater than 3.7 mm.
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Affiliation(s)
- L Walton
- National Centre For Stereotactic Radiosurgery, Royal Hallamshire Hospital, Sheffield, UK
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Walton L, Hampshire A, Forster DM, Kemeny AA. A phantom study to assess the accuracy of stereotactic localization, using T1-weighted magnetic resonance imaging with the Leksell stereotactic system. Neurosurgery 1996; 38:170-6; discussion 176-8. [PMID: 8747966 DOI: 10.1097/00006123-199601000-00038] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
This phantom study assesses the accuracy of stereotactic localization using the Leksell G frame (Elekta Instruments AB, Stockholm, Sweden) with T1-weighted magnetic resonance imaging (Siemens 1.5 T Magnetom; Erlangen, Germany). The coordinates of an array of solid perspex rods were determined and compared with measured values in a series of transverse, coronal, and sagittal images. The maximum absolute errors observed (X = 2.7 mm, Y = 7.0 mm, Z = 8.0 mm) were discouraging. However, the more reasonable mean errors (X = 0.4 mm, Y = 0.7 mm, Z = 1.3 mm) reflect considerable variation in accuracy throughout the volume assessed and limitation of maximum errors to specific areas. We present details of the spatial variation and discuss possible mechanisms for improving accuracy. The overall results are of direct relevance only to the scanner used. These results are, however, an indication of the need to approach with caution stereotactic localization using magnetic resonance imaging and to emphasize the requirement for quality assurance and for a comprehensive study of the scanner's characteristics.
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Affiliation(s)
- L Walton
- Department of Medical Physics and Clinical Engineering, Weston Park Hospital, Sheffield, England
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Abstract
A phantom study has been carried out to assess the accuracy of stereotactic localisation, using magnetic resonance imaging. The stereotactic coordinates of an array of Perspex rods within the phantom were determined and compared with measured values, in a series of transverse, coronal and sagittal images. In the transverse plane, the maximum errors experienced were X = 2.3 mm and Y = 10.7 mm. If the third fiducial plate, at the front of the frame, were not used in the scaling of the images, there was considerable improvement in the Y direction (maximum error Y = 2.1 mm). However, some deterioration in the accuracy in the X direction resulted, particularly at the extremes of Z (maximum error X = 3.5 mm). In the coronal plane, the maximum errors were X = 1.8 mm and Z = 8.0 mm. With the third plate off, the errors decreased to X = 1.9 mm and Z = 3.3 mm. In the sagittal plane, the maximum errors recorded were Y = 1.1 mm and Z = 7.5 mm. It is not possible to calibrate in this plane without the third plate.
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Affiliation(s)
- L Walton
- Department of Medical Physics and Clinical Engineering, Weston Park Hospital, Sheffield, UK
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