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59 result(s) for "Coulthard, Alan"
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Intracranial perianeurysmal cysts: case series and review of the literature
BackgroundIntracranial perianeurysmal cysts are a rare finding associated with cerebral aneurysms. Patients may present with symptoms secondary to mass effect from perianeurysmal cysts requiring drainage. These lesions can masquerade as neoplasms if dedicated vascular imaging is not performed, leading to misdiagnosis.MethodA retrospective search of our database was done for intracranial aneurysms that have been treated between 1998 and 2020. A literature search was then performed on PubMed and Google Scholar with the search terms ‘aneurysm’, ‘intracranial/intracerebral’, ‘cyst’, and ‘perianeurysmal cyst’. Patient demographics, aneurysms and cysts characteristics were then summarized as a table and in the discussion.ResultsThree cases where intracranial aneurysm had associated perianeurysmal cysts were found in our database. Combined with the available literature a total of 19 cases of perianeurysmal cysts have thus far been reported since this entity was first described in 2002. A significant number of perianeurysmal cysts (5/19) required intervention. In 5/19 cases the patient presented with a perianeurysmal cyst without a history of subarachnoid hemorrhage. Of the 10 cases where aneurysm follow-up was reported there were 5 cases where there was aneurysm recurrence necessitating re-treatment.ConclusionSignificant variability exists in the patient demographics, aneurysm and cyst characteristics of perianeurysmal cysts. This suggests that there is no single unified etiology and pathogenesis. These lesions are a rare finding and at present do not appear to carry diagnostic or prognostic significance. Management of perianeurysmal cysts is case-dependent and intervention should be considered when treating the related aneurysm, especially in patients with secondary symptoms.
Peripherally Inserted Central catheter iNnovation to reduce Infections and Clots (the PICNIC trial): a randomised controlled trial protocol
IntroductionPeripherally inserted central catheters (PICCs) are vital for the delivery of medical therapies, but up to 30% of PICCs are associated with complications such as deep vein thrombosis or infection. The integration of antimicrobial and hydrophobic catheter materials, and pressure-activated valves, into polyurethane PICCs are innovations designed to prevent infective and/or thrombotic complications.Methods and analysisA multicentre, parallel group, superiority randomised controlled trial with two experimental arms ((1) hydrophobic PICC (with pressure-activated valve); (2) chlorhexidine gluconate-impregnated PICC (with external clamp)) and one control group ((3) conventional polyurethane PICC (with external clamp)). Recruitment of 1098 adult and paediatric patients will take place over 2 years at three tertiary-referral hospitals in Queensland, Australia. Patients are eligible for inclusion if their PICC is to be inserted for medical treatment, with a vascular size sufficient to support a 4-Fr PICC or larger, and with informed consent. The primary outcome is PICC failure, a composite of thrombotic (venous thrombosis, breakage and occlusion) and infective complications (PICC-associated bloodstream infection and local infection). Secondary outcomes include: all-cause PICC complication; thrombotic complications; infective complications; adverse events (local or systemic reaction); PICC dwell time; patient/parent satisfaction; and healthcare costs. Differences between both intervention groups and the control group will be compared using Cox proportional hazards regression. Effect estimates will be presented as HRs with corresponding 95% CI.Ethics and disseminationEthical approval from Queensland Health (HREC/QCHQ/48682) and Griffith University (Ref. No. 2019/094). Results will be published.Trial registration numberACTRN12619000022167.
Mutation in the gene encoding ferritin light polypeptide causes dominant adult-onset basal ganglia disease
We describe here a previously unknown, dominantly inherited, late-onset basal ganglia disease, variably presenting with extrapyramidal features similar to those of Huntington's disease (HD) or parkinsonism. We mapped the disorder, by linkage analysis, to 19q13.3, which contains the gene for ferritin light polypeptide ( FTL ). We found an adenine insertion at position 460–461 that is predicted to alter carboxy-terminal residues of the gene product. Brain histochemistry disclosed abnormal aggregates of ferritin and iron. Low serum ferritin levels also characterized patients. Ferritin, the main iron storage protein, is composed of 24 subunits of two types (heavy, H and light, L) which form a soluble, hollow sphere 1 . Brain iron deposition increases normally with age, especially in the basal ganglia, and is a suspected causative factor in several neurodegenerative diseases 2 in which it correlates with visible pathology 3 , possibly by its involvement in toxic free-radical reactions 4 . We found the same mutation in five apparently unrelated subjects with similar extrapyramidal symptoms. An abnormality in ferritin strongly indicates a primary function for iron in the pathogenesis of this new disease, for which we propose the name 'neuroferritinopathy'.
Neuroferritinopathy: a new inborn error of iron metabolism
Neuroferritinopathy is an autosomal dominant progressive movement disorder which occurs due to mutations in the ferritin light chain gene ( FTL1 ). It presents in mid-adult life and is the only autosomal dominant disease in a group of conditions termed neurodegeneration with brain iron accumulation (NBIA). We performed brain MRI scans on 12 asymptomatic descendants of known mutation carriers. All three harbouring the pathogenic c.460InsA mutation showed iron deposition; these findings show pathological iron accumulation begins in early childhood which is of major importance in understanding and developing treatment for NBIA.
Liver fat percent is associated with metabolic risk factors and the metabolic syndrome in a high-risk vascular cohort
Objective To determine whether liver fat percent (LFP) is associated with the metabolic syndrome independently of visceral fat area (VFA). Methods 43 High-risk vascular patients not on lipid-lowering therapy were evaluated for the Adult Treatment Panel III (ATPIII) metabolic syndrome criteria and underwent magnetic resonance imaging (MRI) to quantify VFA and subcutaneous fat area (SFA) at the L4-L5 disc and liver magnetic resonance spectroscopy (MRS) to quantify LFP. Comparisons: 1. Baseline differences in patients with and without the metabolic syndrome 2. Forward binary logistic regression analysis of predictors of the metabolic syndrome with VFA, SFA and LFP as independents 3. Correlates of LFP. Results 43 patients were included in analysis. Patients with metabolic syndrome had greater VFA, SFA and LFP than patients without the metabolic syndrome (all p < 0.01). Of VFA, SFA and LFP, only LFP was associated with the diagnosis of the metabolic syndrome on forward binary logistic regression with an OR of 1.17 per 1% increase in LFP (p = 0.015). A 4% LFP threshold identified the metabolic syndrome with 84% sensitivity and 82% specificity. LFP correlated with waist circumference (r = 0.768), HDL-cholesterol (r = -0.342), triglyceride (r = 0.369), fasting glucose (r = 0.584) and the QUICK Index of insulin sensitivity (r = -0.679) (all p < 0.05) Conclusions LFP is associated with the metabolic syndrome and renders the current gold standard of VFA redundant in this analysis. This measure of obesity-related cardiovascular risk requires further validation and evaluation in a prospective cohort.
A Comparison of Peripherally Inserted Central Catheter Materials
New catheter materials for peripherally inserted central catheters (PICCs) may reduce the risk of device failure due to infectious, thrombotic, and catheter occlusion events. However, data from randomized trials comparing these catheters are lacking. We conducted a randomized, controlled, superiority trial in three Australian tertiary hospitals. Adults and children who were referred for PICC placement were assigned in a 1:1:1 ratio to receive a hydrophobic or chlorhexidine PICC or a standard polyurethane PICC and were followed for 8 weeks. The primary outcome was device failure, which was a composite of infectious (bloodstream or local) or noninfectious (thrombosis, breakage, or occlusion) complications. A total of 1098 participants underwent randomization; 365 were assigned to the hydrophobic group, 365 to the chlorhexidine group, and 368 to the standard-polyurethane group. Device failure occurred in 21 of 358 participants (5.9%) in the hydrophobic group, in 36 of 363 (9.9%) in the chlorhexidine group, and in 22 of 359 (6.1%) in the standard-polyurethane group (risk difference, hydrophobic vs. standard polyurethane, -0.2 percentage points [95% confidence interval {CI}, -3.7 to 3.2; P = 0.89]; and chlorhexidine vs. standard polyurethane, 3.8 percentage points [95% CI, -0.1 to 7.8; P = 0.06]). In the hydrophobic group as compared with the standard-polyurethane group, the odds ratio for device failure was 0.96 (95% CI, 0.51 to 1.78), and in the chlorhexidine group as compared with the standard-polyurethane group, the odds ratio was 1.71 (95% CI, 0.98 to 2.99). Complications from any cause during the period of PICC placement occurred in 77 participants (21.5%) in the hydrophobic group, in 140 (38.6%) in the chlorhexidine group, and in 78 (21.7%) in the standard-polyurethane group (odds ratio, hydrophobic vs. standard polyurethane, 0.99 [95% CI, 0.69 to 1.42]; and chlorhexidine vs. standard polyurethane, 2.35 [95% CI, 1.68 to 3.29]). No adverse events were attributable to the interventions. Among adults and children who were referred for PICC placement, the risk of device failure due to noninfectious or infectious complications was not lower with hydrophobic or chlorhexidine PICCs than with standard polyurethane PICCs. (Funded by the National Health and Medical Research Council of Australia; PICNIC Australian New Zealand Clinical Trials Registry number, ACTRN12619000022167.).
An adverse lipid profile and increased levels of adiposity significantly predict clinical course after a first demyelinating event
ObjectiveTo investigate the prospective associations between adiposity and lipid-related variables and conversion to multiple sclerosis (MS), time to subsequent relapse and progression in disability.MethodsA cohort of 279 participants with a first clinical diagnosis of central nervous system demyelination was prospectively followed to 5-year review. Height, weight, waist and hip circumference were measured, and serum samples taken for measurement of lipids and apolipoproteins. Survival analysis was used for conversion to MS and time to relapse, and linear regression for annualised change in disability (Expanded Disability Status Scale).ResultsHigher body mass index (BMI; adjusted HR (aHR): 1.22 (1.04 to 1.44) per 5 kg/m2 increase), hip circumference (aHR: 1.32 (1.12 to 1.56) per 10 cm increase) and triglyceride levels (aHR: 1.20 (1.03 to 1.40) per unit increase) were associated with increased risk of subsequent relapse, while adiposity and lipid-related measures were not associated with conversion to MS. In addition, higher BMI (β: 0.04 (0.01 to 0.07) per 5 kg/m2 increase), hip circumference (β: 0.04 (0.02 to 0.08) per 10 cm increase), waist circumference (β: 0.04 (0.02 to 0.07) per 10 cm increase), total cholesterol to high-density lipoprotein ratio (TC/HDL ratio; β: 0.05 (0.001 to 0.10) and non-HDL; β: 0.04 (0.001 to 0.08) at study entry) were associated with a higher subsequent annual change in disability.ConclusionsHigher levels of adiposity, non-HDL and TC/HDL ratio were prospectively associated with a higher rate of disability progression, and higher adiposity and triglycerides were associated with relapse but not with conversion to MS. Improving the lipid profile and losing weight into the healthy range could reduce the accumulation of disability.
Direct evidence of intra- and interhemispheric corticomotor network degeneration in amyotrophic lateral sclerosis: An automated MRI structural connectivity study
Although the pathogenesis of amyotrophic lateral sclerosis (ALS) is uncertain, there is mounting neuroimaging evidence to suggest a mechanism involving the degeneration of multiple white matter (WM) motor and extramotor neural networks. This insight has been achieved, in part, by using MRI Diffusion Tensor Imaging (DTI) and the voxelwise analysis of anisotropy indices, along with DTI tractography to determine which specific motor pathways are involved with ALS pathology. Automated MRI structural connectivity analyses, which probe WM connections linking various functionally discrete cortical regions, have the potential to provide novel information about degenerative processes within multiple white matter (WM) pathways. Our hypothesis is that measures of altered intra- and interhemispheric structural connectivity of the primary motor and somatosensory cortex will provide an improved assessment of corticomotor involvement in ALS. To test this hypothesis, we acquired High Angular Resolution Diffusion Imaging (HARDI) scans along with high resolution structural images (sMRI) on 15 patients with clinical evidence of upper and lower motor neuron involvement, and 20 matched control participants. Whole brain probabilistic tractography was applied to define specific WM pathways connecting discrete corticomotor targets generated from anatomical parcellation of sMRI of the brain. The integrity of these connections was interrogated by comparing the mean fractional anisotropy (FA) derived for each WM pathway. To assist in the interpretation of results, we measured the reproducibility of the FA summary measures over time (6months) in control participants. We also incorporated into our analysis pipeline the evaluation and replacement of outlier voxels due to head motion and physiological noise. When assessing corticomotor connectivity, we found a significant reduction in mean FA within a number of intra- and interhemispheric motor pathways in ALS patients. The abnormal intrahemispheric pathways include the corticospinal tracts involving the left and right precentral gyri (lh.preCG, rh.preCG) and brainstem (bs); right postcentral gyrus (rh.postCG) and bs; lh.preCG and left posterior cingulate gyrus (lh.PCG); rh.preCG and right posterior cingulate gyrus (rh.PCG); and the rh.preCG and right paracentral gyrus (rh.paraCG). The abnormal interhemispheric pathways included the lh.preCG and rh.preCG; lh.preCG and rh.paraCG; lh.preCG and right superior frontal gyrus (rh.supFG); lh.preCG and rh.postCG; rh.preCG and left paracentral gyrus (lh.paraCG); rh.preCG and left superior frontal gyrus (lh.supFG); and the rh.preCG and left caudal middle frontal gyrus (lh.caudMF). The reproducibility of the measurement of these pathways was high (variation less than 5%). Maps of the outlier rejection voxels, revealed clusters within the corpus callosum and corticospinal projections. This finding highlights the importance of correcting for motion artefacts and physiological noise when studying clinical populations. Our novel findings, many of which are consistent with known pathology, show extensive involvement and degeneration of multiple corticomotor pathways in patients with upper and lower motor neuron signs and provide support for the use of automated structural connectivity techniques for studying neurodegenerative disease processes. ► MRI reveals loss of intra- and interhemispheric white matter connectivity in ALS. ► MRI structural connectivity measures are highly reproducible. ► Motion artifact and physiological noise may compromise connectivity analyses.