Forensic age estimation based on magnetic resonance imaging of third molars: converting 2D staging into 3D staging

Background: Established methods to stage development of third molars for forensic age estimation are based on the evaluation of radiographs, which show a 2D projection. It has not been investigated whether these methods require any adjustments in order to apply them to stage third molars on magnetic resonance imaging (MRI), which shows 3D information.

Aim: To prospectively study root stage assessment of third molars in age estimation using 3 Tesla MRI and to compare this with panoramic radiographs, in order to provide considerations for converting 2D staging into 3D staging and to determine the decisive root.

Subjects and methods: All third molars were evaluated in 52 healthy participants aged 14–26 years using MRI in three planes. Three staging methods were investigated by two observers. In sixteen of the participants, MRI findings were compared with findings on panoramic radiographs.

Results: Decisive roots were palatal in upper third molars and distal in lower third molars. Fifty-seven per cent of upper third molars were not assessable on the radiograph, while 96.9% were on MRI. Upper third molars were more difficult to evaluate on radiographs than on MRI (p?p?=?.375). Inter- and intra-observer agreement for evaluation was higher in MRI than in radiographs. In both imaging techniques lower third molars showed greater inter- and intra-observer agreement compared to upper third molars. MR images in the sagittal plane proved to be essential for staging.

Conclusion: In age estimation, 3T MRI of third molars could be valuable. Some considerations are, however, necessary to transfer known staging methods to this 3D technique.     

Unreliable post event report from an automated external defibrillator

Medical supervision of the use of automated external defibrillators (AEDs) is possible by the incorporation of a solid state memory system recording electrocardiography (ECG) tracings and information about the operation of the device. Since a post event report suggested inappropriate AED use erroneously, the information storage and printing processes of the Laerdal® AED system were investigated. This analysis strongly suggests (yet unpredictable) incompatibilities between the software built in the solid state memory modules and the different components of the printing system. Although no problems were encountered during the resuscitation attempts, these findings may be clinically relevant because an unreliable post event report from a solid state memory module may lead to erroneous criticism of an AED user.

Abstract

A supervisão médica do uso de desfibrilhadores automáticos externos (DAE) é possível através da incorporação de sistemas de memória permanente que gravam os traçados electrocardiográficos (ECG) e fornecem informação sobre o funcionamento do aparelho. Desde que um relato post-incidente sugeriu erradamente uma utilização inadequada do DAE, foram investigados os processos de impressão e armazenamento de informação do sistema DAE Laerdal. Esta análise sugere fortemente (mas não permite prever) a existência de incompatibilidades entre o software dos sistemas de memória e os componentes do sistema de impressão. Apesar de não terem sido detectados problemas em reanimações, estes achados podem vir a ter significado clínico relevantes já que relatos post-incidente de um módulo de memória, pouco fiáveis, podem provocar críticas erradas quanto á utilização de um DAE.     

Structural brain network imaging shows expanding disconnection of the motor system in amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a severe neurodegenerative disease, which primarily targets the motor system. The structural integrity of the motor network and the way it is embedded in the overall brain network is essential for motor functioning. We studied the longitudinal effects of ALS on the brain network using diffusion tensor imaging and questioned whether over time an increasing number of connections become involved or whether there is progressive impairment of a limited number of connections. The brain network was reconstructed based on “whole brain” diffusion tensor imaging data. We examined: (1) network integrity in 24 patients with ALS at baseline (T = 1) and at a more advanced stage of the disease (T = 2; interval 5.5 months) compared with a group of healthy controls and (2) progressive brain network impairment comparing patients at two time‐points in a paired‐analysis. These analyses demonstrated an expanding subnetwork of affected brain connections over time with a central role for the primary motor regions (P‐values T = 1 0.003; T = 2 0.001). Loss of structural connectivity mainly propagated to frontal and parietal brain regions at T = 2 compared with T = 1. No progressive impairment of the initially affected (motor) connections could be detected. The main finding of this study is an increasing loss of network structure in patients with ALS. In contrast to the theory of ALS solely affecting a fixed set of primary motor connections, our findings show that the network of impaired connectivity is expanding over time. These results are in support of disease spread along structural brain connections. Hum Brain Mapp 35:1351–1361, 2014. © 2013 Wiley‐Periodicals, Inc.     

Outcome in noninvasively and invasively ventilated hematologic patients with acute respiratory failure

STUDY OBJECTIVES: The survival rate of patients with a hematologic malignancy requiring mechanical ventilation (MV) in the ICU has improved over the last few decades. The objective of this study was to identify the factors affecting the in-hospital mortality of these particular patients, and to assess whether the use of noninvasive positive pressure ventilation (NPPV) was protective in our study population. DESIGN: We retrospectively collected variables in 166 consecutive patients with hematologic malignancies who had acute respiratory failure (ARF) requiring MV, and identified factors obtained within 24 h of ICU admission affecting in-hospital mortality in univariate and multivariate stepwise logistic regression analyses. The effect of NPPV on mortality was assessed using a pair-wise matched exposed-unexposed analysis. RESULTS: The mean simplified acute physiology score (SAPS) II was 58.9. The in-hospital mortality rate was 71%. In a multivariate logistic regression analysis, the in-hospital mortality rate was predicted by increasing severity of illness, as measured by SAPS II (odds ratio [OR] per point of increase, 1.07; 95% confidence interval [CI], 1.04 to 1.11) and a diagnosis of acute myelogenous leukemia (OR, 2.73; 95% CI, 1.05 to 7.11). Female sex (OR, 0.36; 95% CI, 0.16 to 0.82), endotracheal intubation (ETI) within 24 h of ICU admission (OR, 0.29; 95% CI, 0.11 to 0.78), and recent bacteremia (defined as blood cultures positive for bacteria < 48h before or < 24h after ICU admission) [OR, 0.22; 95% CI, 0.08 to 0.61] were associated with a lower mortality rate. Twenty-seven patients who received NPPV were matched for SAPS II (+/- 3) with 52 patients who required immediate ETI on a 1:2 basis. The crude in-hospital mortality rate was 65.4% in both groups. CONCLUSION: Although the in-hospital mortality rate in hematologic patients who develop ARF remains high, the reluctance to intubate and start treatment with invasive MV in this population is unjustified, especially when bacteremia has precipitated ICU admission.     

Outcome and attributable mortality in critically Ill patients with bacteremia involving methicillin-susceptible and methicillin-resistant Staphylococcus aureus

BACKGROUND: Staphylococcus aureus bacteremia carries high mortality rates. The clinical impact of methicillin resistance remains controversial: outcome comparisons between patients with bacteremia involving methicillin-susceptible (MSSA) and methicillin-resistant (MRSA) S aureus are difficult to perform because of important differences in severity of illness. METHODS: A retrospective cohort analysis and 2 independent case-control analyses were performed to determine and compare outcomes and attributable mortality rates of MSSA (n = 38) and MRSA bacteremia (n = 47) in critically ill patients. For the case-control studies, matching (1:2 ratio) was based on the APACHE (Acute Physiology and Chronic Health Evaluation) II classification: APACHE II score (+/-1 point) and diagnostic category. RESULTS: Patients with MRSA bacteremia had more acute renal failure and hemodynamic instability than patients with MSSA bacteremia. They had a longer intensive care unit stay and ventilator dependency. Patients with MRSA bacteremia had a higher 30-day mortality rate (53.2% vs 18.4%) and in-hospital mortality rate (63.8% vs 23.7%) (P<.05). Multivariate survival analysis demonstrated acute renal failure, length of mechanical ventilation, age, and methicillin resistance to be independently associated with mortality (P<.05). The attributable mortality rate for MSSA bacteremia was 1.3%: mortality rates for cases and controls were respectively 23.7% and 22.4% (P =.94). The attributable mortality rate for MRSA bacteremia was 23.4%: mortality rates for cases and controls were respectively 63.8% and 40.4% (P =.02). The difference (22.1%) between both attributable mortality rates was significant (95% confidence interval, 8.8%-35.3%). CONCLUSION: In critically ill patients, after accurate adjustment for disease severity and acute illness, we found MRSA bacteremia to have a higher attributable mortality than MSSA bacteremia.     

Soluble urokinase-type plasminogen activator receptor levels in patients with burn injuries and inhalation trauma requiring mechanical ventilation: an observational cohort study

Introduction  

Soluble urokinase-type plasminogen activator receptor (suPAR) has been proposed as a biologic marker of fibrinolysis and inflammation. The aim of this study was to investigate the diagnostic and prognostic value of systemic and pulmonary levels of suPAR in burn patients with inhalation trauma who need mechanical ventilation.     

Cystic Tumors of the Pancreas: Ultrasound, Computed Tomography, and Magnetic Resonance Imaging Features

Cystic tumors of the pancreas are a subset of rare pancreatic tumors that vary from benign to malignant. Many have specific imaging findings that allow them to be differentiated from each other. This article aims to review the histopathologic and imaging findings of the relatively common lesions (serous microcystic adenoma, mucinous cystic tumor, intraductal papillary mucinous tumor, and solid pseudopapillary tumor) and uncommon lesions (cystic endocrine tumors, cystic metastases, cystic teratomas, and lymphangiomas) in this group.