Volumetric relief map for intracranial cerebrospinal fluid distribution analysis

International audienceCerebrospinal fluid imaging plays a significant role in the clinical diagnosis of brain disorders, such as hydrocephalus and Alzheimer's disease. While three-dimensional images of cerebrospinal fluid are very detailed, the complex structures they contain can be time-consuming and laborious to interpret. This paper presents a simple technique that represents the intracranial cerebrospinal fluid distribution as a two-dimensional image in such a way that the total fluid volume is preserved. We call this a volumetric relief map, and show its effectiveness in a characterization and analysis of fluid distributions and networks in hydrocephalus patients and healthy adults

Volumetric relief map for the cortical subarachnoid space analysis

Purpose: Medical image visualization is an important step in the medical diagnosis of hydrocephalus. In this paper, we present planar representations called volumetric relief maps that are generated from three-dimensional images of the cerebrospinal fluid within the cortical subarachnoid space. Such maps are visually interpreted at once and allow to automatically characterize fluid distributions. Consequently, they help specialists to provide a diagnosis and to monitor patients instantly. Methods: Volumetric relief maps are generated by enclosing the cortical subarachnoid space with a hemisphere, and using a ray tracing method and a map projection technique from a hemisphere to a plane. Results: Visualization of maps indicates that healthy adults have more balanced fluid distributions with well-filled sulci, unlike hydrocephalus patients who have more or less large fluid depletions in the posterior regions of the brain. We showed that a moment-based approach allows to efficiently characterize such fluid distributions from maps. In particular, the center of mass of a distribution is an efficient discriminant factor to distinguish between healthy adults and hydrocephalus patients, with resulting sensitivity and specificity of 100%. In addition, we have noted that asymmetry of the fluid distribution increases with depletion for hydrocephalus patients; such asymmetry is generally oriented towards the frontal part of the fissura longitudinalis cerebri. Conclusions: This paper describes an innovative visualization tool used to analyze fluid distribution within the cortical subarachnoid space. It allows to efficiently discriminate between healthy adults and pathological cases, and to monitor patients before and after surgery

Predictors of in-hospital mortality in elderly patients with bacteraemia admitted to an Internal Medicine ward

BACKGROUND: Infectious diseases are a common cause of increased morbidity and mortality in elderly patients. Bacteraemia in the elderly is a difficult diagnosis and a therapeutic challenge due to age-related vicissitudes and to their comorbidities. The main purpose of the study was to assess independent risk factors for in-hospital mortality among the elderly with bacteraemia admitted to an Internal Medicine Ward. METHODS: Overall, a cohort of 135 patients, 65 years of age and older, with bacteraemia were retrospectively studied. Data related to demographic information, comorbidities, clinical parameters on admission, source and type of infection, microorganism isolated in the blood culture, laboratory data and empirical antibiotic treatment was recorded from each patient. Multivariate logistic regression was performed to identify independent predictors of all-cause in-hospital mortality. RESULTS: Of these 135 patients, 45.9% were women. The most common infections in this group of patients were urinary tract infections (46.7%). The main microorganisms isolated in the blood cultures were Escherichia coli (14.9%), Methicillin-resistant Staphylococcus aureus (MRSA) (12.0%), non-MRSA (11.4%), Klebsiella pneumoniae (9.1%) and Enterococcus faecalis (8.0%). The in-hospital mortality was 22.2%. Independent prognostic factors associated with in-hospital mortality were age ≥ 85 years, chronic renal disease, bacteraemia of unknown focus and cognitive impairment at admission (OR, 2.812 [95% CI, 1.039-7.611; p = 0.042]; OR, 6.179 [95% CI, 1.840-20.748; p = 0.003]; OR, 8.673 [95% CI, 1.557-48.311; p = 0.014] and OR, 3.621 [95% CI, 1.226-10.695; p = 0.020], respectively). By multivariate analysis appropriate antibiotic therapy was not associated with lower odds of mortality. CONCLUSION: Bacteraemia in the elderly has a high mortality rate. There are no set of signs or clinical features that can predict bacteraemia in the elderly. However, older age (≥ 85 years), chronic renal disease, bacteraemia of unknown focus and severe cognitive impairment adversely affects the outcome of elderly patients with bacteraemia admitted to an Internal Medicine ward

What is the impact of physical effort on the diagnosis of concussion?

Objective: Sport-related concussion commonly occurs in contact sports such as rugby. To date, diagnosis is based on the realization of clinical tests conducted pitch-side. Yet, the potential effect of prior physical effort on the results of these tests remains poorly understood. The purpose of this study was to determine whether preceding physical effort can influence the outcome of concussion assessments. Design: Prospective observational study. Setting: University Medicine Center Patients: A cohort of 40 subjects (20 rugby players and 20 athletes from a range of sports). Intervention: A concussion assessment was performed immediately following physical activity. Following a period of 6 months and under the same experimental conditions, the same cohort performed the same tests in resting conditions. Main outcome measure: Results of concussion tests. Results: In both cohorts, the comparison for post-exercise and rest assessments demonstrated a most likely moderate-to-very large increase in the number of symptoms, severity of symptoms and BESS score. In the rugby cohort, scores for concentration, delayed memory and SAC, likely-to-most likely decreased following completion of physical activity compared to baseline values. The between-cohort comparison showed a greater impact post-exercise in the rugby players for delayed recall (0.73±0.61, 93/7/1) and SAC score (0.75±0.41, 98/2/0). Conclusion: Physical activity altered the results of concussion diagnostic tests in athletes from a range of sports and notably in rugby players. Therefore, physical efforts prior to the concussion incident should be accounted for during pitch-side assessments and particularly during rugby competition and training

Apolipoprotein E epsilon-4 polymorphism is associated with younger age at referral to a lipidology clinic and a poorer response to lipid-lowering therapy

<p>Abstract</p> <p>Background</p> <p>The risk of coronary heart disease (CHD) is related to environmental factors and genetic variants. Apolipoprotein E (apoE) polymorphisms are heritable determinants of total and low-density lipoprotein cholesterol, with some authors suggesting an association between the ε4 allele and CHD. We investigated the relationship between apoE genotype and age at referral to a specialized lipid clinic by the primary care physician and whether the benefits of treatment with statin differed between genotypes.</p> <p>Methods</p> <p>We assessed individual apoE genotypes and lipid blood profile in a total of 463 patients followed at a specialized lipid clinic due to dyslipidemia, with a 3-year median follow-up time. The primary care physician at the time of the referral had no access to the apoE genotyping results. Carriers of apoE ε4/ε2 genotype were excluded.</p> <p>Results</p> <p>The frequencies of ε2, ε3 and ε4 alleles were 7.8, 78.9 and 13.3%, respectively. There were no significant differences between genders. Although with similar lipid profiles and antidyslipidemic drug usage at baseline, ε4-carriers were referred to the clinic at a younger age (44.2 ± 14.7 years) compared with non-ε4 carriers (50.6 ± 13.8 years) (p < 0.001), with a substantially younger age of referral for homozygous E4/4 and for all genotypes with at least one copy of the ε4 allele (p < 0.001 for trend). Although both ε4 and non-ε4 carriers achieved significant reductions in total cholesterol during follow-up (p < 0.001 vs. baseline), the mean relative decrease in total cholesterol levels was higher in non-ε4 carriers (-19.9 ± 2.3%) compared with ε4 carriers (-11.8 ± 2.3%), p = 0.003.</p> <p>Conclusion</p> <p>Our findings support the concept that there is a reduced response to anti-dyslipidemic treatment in ε4 carriers; this can be a contributing factor for the earlier referral of these patients to our specialized lipid clinic and reinforces the usefulness of apoE genotyping in predicting patients response to lipid lowering therapies.</p

Intra cranial volume quantification from 3D reconstruction based on CT-scan data

The evolution of some congenital diseases impacting the shape of the skull such as the Chiari malformation or Craniosynostosis condition can be quantify measuring the increasing of the intra cranial volume (ICV) (Gault et al. 1993). This volume could be calculated from ana-tomic measurements (Gordon 1966). Nevertheless, in case of important variations of shape, these techniques were not suitable to accurately assess ICV from measure-ments of global parameters. Some studies, using automatic segmentation combined with manual adjustments from MRI acquisition were used to assess the ICV (Reite et al. 2010). However, 3-4 hours were required for each patient to complete the process. Other studies used total auto-matic segmentation to calculate volume of the brain and the ICV (de Jong et al. 2017). But high quality of MRI was necessary to get accurate results.The purpose of this study was to develop a fast, efficient and reproducible procedure to calculate the ICV, based on 3D skull reconstruction obtained from scanner imaging

It’s time to give concussion an operational definition: A 3-step process to diagnose (or rule out) concussion within 48 hours of injury: World Rugby Guideline

World Rugby has introduced an operational definition of concussion into Rugby to better identify and manage concussion and to support injury surveillance studies. This definition acknowledges the variability in clinical concussion presentation by incorporating a three-point in time diagnostic process with the recommended times aligning with the times that team doctor’s normal responsibilities involve team contact. The current content of each assessment is based on SCAT 3 and will continue to be modified as the evidence around concussion diagnosis evolves. This operational definition of concussion also includes the recommendation that any abnormal assessment be considered as being due to concussion. This default can be overruled if the team doctor decides that the abnormal assessment is not related to a concussion. Finally with World Rugby’s operational definition, a concussion following a head injury cannot be excluded until an assessment is completed at 36-48 hours post injury.The authors gratefully acknowledge the support and input of the following members of the IRB HIA working group for their expert recommendations. Roles identified were those at time of working group involvement: Conor McCarthy (Irish RFU Medical Director), Deborah Robinson (New Zealand Rugby Union Team Physician), Rob Nichol (CEO International Rugby Players' Association), Vincenzo Ieracitano (Chairman Medical Commission of Italian FIR), Mike England (Director English RFU Injured Players Foundation), Paul Watson (Medical Director Rugby Canada); Eanna Falvey (Team Physician Irish Rugby Union), Mark Harrington (IRB Training and Medical Manager – World Rugby representative

Quantification of the stress generated by theendoscopic movement in the brain parenchymaduring intra ventricular surgical procedure

Endoscopy is increasingly used for intra ventricular surgeries such as hydrocephalus and tumor removal (Miwa et al. 2015 Miwa T, Hayashi N, Endo S, Ohira T. 2015. Neuroendoscopic biopsy and the treatment of tumor-associated hydrocephalus of the ventricular and paraventricular region in pediatric patients: a nationwide study in Japan. Neurosurg Rev.[Crossref], [PubMed], [Web of Science ®], , [Google Scholar]). Robotic based surgeries are more and more developed to control the trajectory and the movement of the endoscope and then to enhance the accuracy of surgical procedures and to reduce post-operative issues. The use of computer- aided robot is then well-suited to accurately reach ventricles cavities through the brain parenchyma and to minimize cerebral damage caused by the movement of the endoscope. On a mechanical point of view, moderate and severe traumatic brain injury (TBI) had a 50% risk to locally occur when Von Mises stress respectively exceeds 18 and 38 kPa (Willinger & Baumgartner 2003 Willinger R, Baumgartner D. 2003. Human head tolerance limits to specific injury mechanisms. Int J Crashworthiness.[Taylor & Francis Online], , [Google Scholar]). The purpose of this study was to assess the Von Mises stress generated in the brain by the endoscopic movement