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K J Carson

Publications and source records attributed to K J Carson.

7 recordsLinked to original sources
PubMed2006

The role of PET/CT scanning in radiotherapy planning.

The introduction of functional data into the radiotherapy treatment planning process is currently the focus of significant commercial, technical, scientific and clinical development. The potential of such data from positron emission tomography (PET) was recognized at an early stage and was integrated into the radiotherapy treatment planning process through the use of image fusion software. The combination of PET and CT in a single system (PET/CT) to form an inherently fused anatomical and functional dataset has provided an imaging modality which could be used as the prime tool in the delineation of tumour volumes and the preparation of patient treatment plans, especially when integrated with virtual simulation. PET imaging typically using 18F-Fluorodeoxyglucose (18F-FDG) can provide data on metabolically active tumour volumes. These functional data have the potential to modify treatment volumes and to guide treatment delivery to cells with particular metabolic characteristics. This paper reviews the current status of the integration of PET and PET/CT data into the radiotherapy treatment process. Consideration is given to the requirements of PET/CT data acquisition with reference to patient positioning aids and the limitations imposed by the PET/CT system. It also reviews the approaches being taken to the definition of functional/tumour volumes and the mechanisms available to measure and include physiological motion into the imaging process. The use of PET data must be based upon a clear understanding of the interpretation and limitations of the functional signal. Protocols for the implementation of this development remain to be defined, and outcomes data based upon clinical trials are still awaited.

Humans↗
PubMed2002

Diagnostic value of high signal abnormalities on T2 weighted MRI in the differentiation of Alzheimer's, frontotemporal and vascular dementias.

OBJECTIVE: The occurrence of high signal abnormalities on T2 weighted images is strongly age related. The diagnostic value of these changes in a younger population with dementia is not currently known. We studied the potential of high signal changes on magnetic resonance imaging (MRI) in differentiating Alzheimer's disease (AD), frontotemporal dementia (FTD) and vascular dementia (VaD) in younger patients. METHODS: High signal abnormalities were rated, using a previously validated scale, from hard copies of T2 weighted axial images of 102 patients with AD (n=49), VaD (n=31), FTD (n=22) (mean ages 63-65 years). RESULTS: High signal abnormalities were widespread across AD, VaD and FTD. Although they were most frequent and most severe in the VaD group only lacunes and grade III deep white matter hyperintensities (DWMH) were specific for these patients. CONCLUSIONS: High signal changes on T2 weighted images on MRI are common across degenerative (AD and FTD) and vascular dementias. Although lacunes and grade III DWMH are specific for VaD, the low sensitivities (sensitivities: for lacunes, 0.32; for grade III DWMH, 0.16) limit their use as diagnostic markers for VaD. High signal changes on MRI should be interpreted with caution in dementias. Their presence, even in younger patients, should not deter one from diagnosing AD or FTD.

Aged↗
PubMed2002

Diagnostic patterns of regional atrophy on MRI and regional cerebral blood flow change on SPECT in young onset patients with Alzheimer's disease, frontotemporal dementia and vascular dementia.

OBJECTIVES: Alzheimer's disease (AD), frontotemporal dementia (FTD) and vascular dementia (VaD) are the three most common causes of young onset dementias. Most neuroimaging studies of these disorders have involved comparisons with normal controls. The aims of this study were to examine the clinical diagnostic value of magnetic resonance imaging (MRI) and single photon emission computed tomography (SPECT) (in combination and in isolation) in the differentiation of one form of dementia from another from amongst a group of AD, FTD and VaD. METHODS: T1 weighted MRI images and 99mTc-HMPAO SPECT images were obtained from consecutive patients with FTD (n=21), AD (n=23) and VaD (n=20) and rated visually by experienced neuroradiologists and nuclear medicine physicians. RESULTS: Asymmetrical atrophy was seen only in FTD. Frontotemporal dementia patients were the most atrophic whereas severe atrophy was rarely observed in VaD. Severe frontal atrophy (unilaterally or bilaterally) and/or asymmetrical atrophy on MRI is highly diagnostic (sensitivity 0.71, specificity 0.93, LR 10.24) of FTD from within a group of FTD and non-FTD (AD, VaD) patients. Mild or severe parietal atrophy with severe reduction in parietal regional cerebral blood flow on SPECT is diagnostic (sensitivity 0.71, specificity 0.76, LR 3.02) of AD from within a group of AD and non-AD (VaD, FTD) patients. CONCLUSION: Anatomical (MRI) and functional (SPECT) imaging provide different information and a combination of these modalities improves diagnostic specificity.

Aged↗
PubMed1994

Tinfoil roses.

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Christianity↗
PubMed1994

Electrocardiographic changes in critically ill adults during intrahospital transport.

Critically ill patients are frequently transported out of the intensive care unit (ICU) for diagnostic tests and procedures. Advanced diagnostic testing and increased patient acuity have influenced the level of nursing care required during intrahospital transport. Previous studies have documented deleterious patient outcomes during intrahospital transport, but none have evaluated twelve lead electrocardiograms (ECGs). Using a prospective design, this study sought to describe ECG changes during intrahospital transport. A secondary purpose was to describe the nursing implications of transporting the patients in this sample. A convenience sample of 29 critical care patients (14 cardiac, 8 neurological, 5 medical, 2 transplant) was selected from three ICUs at a university hospital. In addition to the standard, single bipolar lead monitor, patients were monitored with a portable, interpretative electrocardiograph with continuous 12 lead ST segment analysis. Results of this study indicate that cardiac events during intrahospital transport may go undetected because of current monitoring practices and the mechanics of transport.

Adult↗