Search

Purpose: To compare single-photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI) in a cohort of patients examined for suspected dementia, including patients with no objective cognitive impairment (control group), mild cognitive impairment (MCI), and Alzheimer's disease (AD). Material and Methods: Twenty-four patients, eight with AD, 10 with MCI, and six controls were investigated with SPECT using 99mTc-hexamethylpropyleneamine oxime (HMPAO) and dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) with gadobutrol. Three observers performed a visual interpretation of the SPECT and MR images using a four-point visual scale. Results: SPECT was superior to DSC-MRI in differentiating normal from pathological. All three observers showed statistically significant results in discriminating between the control group, AD, and MCI by SPECT, with a P value of 0.0006, 0.04, and 0.01 for each observer. The statistical results were not significant for MR ( P values 0.8, 0.1, and 0.2, respectively). Conclusion: DSC-MRI could not replace SPECT in the diagnosis of patients with Alzheimer's disease. Several patient- and method-related improvements should be made before this method can be recommended for clinical practice.

While in service, pipelines may from time to time be exposed to impact loads from anchors or trawl gear. A lot of parameters influence the behaviour of the pipeline during impact, e.g. the diameter and thickness of the pipeline, the impactor's mass and velocity, and of course the material used. Also potentially influencing the deformation pattern is the presence of surrounding water, which can be a difficult parameter to include experimentally. The pressurised contents of the pipeline can also be an influencing factor. To gain some insight into how the water and possible pressure inside the pipeline affect the global impact behaviour, numerical investigations have been carried out using FSI- techniques available in the explicit finite element code Europlexus. One case was set up for validation against available experimental data, and additional cases examined numerically the effect of including pressure and/or surrounding water. The simulations generally captured the deformation and load levels from the experiments well, and may be assumed to represent the events with reasonable accuracy. Adding internal pressure generally led to a higher peak load, and created a more localised deformation. Submerging the pipe in water seemed to be of minor importance with respect to global and local deformation, but this depended heavily on the FSI conditions. Other parameters than the surrounding water, which for design purposes may be omitted, appear to be more significant to the global and local response., JRC.G.5-European laboratory for structural assessment

Purpose: To evaluate exfoliative glaucoma (XFG) patients over 5 years, determining risk factors associated with progression or non-progression of glaucoma. Methods: A retrospective, observational study. Patients were chosen from consecutive charts and data collected from each available visit included in the follow-up period. Data were abstracted for non-progressed XFG patients for 5 years and for progressed patients until glaucoma worsened. Progression was determined from patient records and by disc photographs. Results: There were 71 (53%) progressed and 63 (47%) non-progressed XFG patients.Baseline parameters demonstrated worse visual field damage (p = 0.014) and more prescribed medicines (p = 0.03) in progressed patients. The mean intraocular pressure (IOP) for progressed patients was 18.7 ± 4.3 and 17.3 ± 3.4 mm Hg for non-progressed patients (p = 0.047). The mean IOP that best separated the groups was 17 mm Hg with 60% staying non-progressed at or below this level and 30% above this level. At the last visit, progressed patients had more medicines prescribed (1.7) than non-progressed patients (1.3, p = 0.005). A multivariate regression analysis showed higher mean, peak and variance of IOP, number of glaucoma medications at the final visit and presence of a disc hemorrhage (n = 5) as independent risk factors for progression (p ≤ 0.05). Conclusion: IOP reduction in XFG may be essential in reducing disease progression. The presence of disc hemorrhage in XFG may suggest an increased probability of progression despite treatment to within the normal IOP range.