Anatomic Study of Mandibular Posterior Teeth Using Cone-beam Computed Tomography for Endodontic Surgery

Introduction

The present study aimed to anatomically assess mandibular posterior teeth using cone-beam computed tomographic (CBCT) imaging for endodontic surgery.

Brain mucormycosis in a child with acute lymphoblastic leukemia

This article reports a rare case of Brain Mucormycosis in a 12 year-old girl who presented with relapse Acute Lymphoblastic Leukemia (ALL). On the 12th day of chemotherapy, although there was no CNS symptoms, the second Lumbar Puncture (LP) revealedmthe CNS relapse which developed to Into brain abscess presenting with right side hemiparesis. The brain magnetic resonance imaging (MRI) and the brain biopsy revealed small, multifocal necrosis and acute inflammation with septal fungal hyphae branching, which was proven to be caued by Mucormycosis according to Polymerase Chain Reaction (PCR). The patient responded to treatment with intravenous liposomal Amohotericin B and Caspofungin after two months, suggesting that Brain Mucormycosis in ALL cases can be managed with sequential therapy by antifungals.     

Predictors of survival in patients with sarcoma admitted to the intensive care unit

Background

Advances in treatment of sarcoma patients has prolonged survival but has led to increased disease- or treatment-related complications resulting in greater number of admissions to the intensive care unit (ICU). Survival and long-term outcome information about such critically ill patients with sarcoma is unknown.

Methods

The primary objective of the study was to determine the ICU and post-ICU survival rates of critically ill sarcoma patients. Secondary objectives included determining the modifiable and non-modifiable predictors of poor survival. We performed a retrospective chart review of sarcoma patients admitted to the ICU at The University of Texas MD Anderson Cancer Center between January 1, 2005, and December 31, 2012. Main outcome measures were ICU mortality, in-hospital mortality and 1, 2, and 6-month survival rates. Covariates such as histological diagnosis, disease characteristics, chemotherapy use, Charlson comorbidity index, Sequential Organ Failure Assessment (SOFA) scores, and clinical findings leading to ICU admission were analyzed for their effects on survival.

Results

We identified 172 admissions over the 8-year study period hat met our inclusion criteria. The study population was 45.9 % males with a median age of 52 years. The most common sarcoma subgroups were high-grade unclassified sarcoma (25 %) and bone tumors (17.4 %). The ICU mortality rate was 23.3 % (95 % confidence interval [CI], 16.9–29.6 %), and an additional 6.4 % of patients died before hospital discharge (95 % CI, 22.9–37.1 %). 6-month OS rates were 41 %. The median SOFA scores on admission were 6 (inter quartile range (IQR), 3.5–9) in ICU survivors and 10 (IQR, 6.5–14) in ICU non-survivors. Increase in SOFA scores ≥6 led to poor outcomes (ICU survival 13.3 %, OS 6.7 %). Charlson comorbidity index (HR 1.139, 95 % CI 1.023–1.268, p = 0.02) and discharge SOFA scores (HR 1.210, 95 % CI 1.141–1.283, p < 0.0001) correlated with overall survival.

Conclusions

Our results suggest that patients that are admitted to the ICU for respiratory failure, cardiac arrest, septic shock, acute renal failure or acidosis and also have a high SOFA score with subsequent worsening in the ICU have poor prognosis. Based on the retrospective data which needs further validation we can recommend that judicious approach should be taken in patients with predictors of poor survival before subjecting them to aggressive treatment.

     

Predicting White Matter Integrity from Multiple Common Genetic Variants

Several common genetic variants have recently been discovered that appear to influence white matter microstructure, as measured by diffusion tensor imaging (DTI). Each genetic variant explains only a small proportion of the variance in brain microstructure, so we set out to explore their combined effect on the white matter integrity of the corpus callosum. We measured six common candidate single-nucleotide polymorphisms (SNPs) in the COMT, NTRK1, BDNF, ErbB4, CLU, and HFE genes, and investigated their individual and aggregate effects on white matter structure in 395 healthy adult twins and siblings (age: 20–30 years). All subjects were scanned with 4-tesla 94-direction high angular resolution diffusion imaging. When combined using mixed-effects linear regression, a joint model based on five of the candidate SNPs (COMT, NTRK1, ErbB4, CLU, and HFE) explained ∼6% of the variance in the average fractional anisotropy (FA) of the corpus callosum. This predictive model had detectable effects on FA at 82% of the corpus callosum voxels, including the genu, body, and splenium. Predicting the brain''s fiber microstructure from genotypes may ultimately help in early risk assessment, and eventually, in personalized treatment for neuropsychiatric disorders in which brain integrity and connectivity are affected.     

Unveiling epileptogenic lesions: the contribution of image processing

Magnetic resonance imaging (MRI) is a pivotal component in the investigation of patients with any form of epilepsy because of its unmatched ability in visualizing structural brain pathology. The MRI signature of newly diagnosed epilepsy is not yet fully defined, mainly because of the lack of a cohesive methodology to evaluate structural changes in the early stages of the disease. By revealing subtle lesions that previously eluded visual inspection in patients with drug-resistant epilepsy, quantitative computer-assisted image analysis has clearly demonstrated increased sensitivity and diagnostic accuracy compared to conventional techniques. Therefore, the application of image processing methods in patients with newly diagnosed epilepsy promises to reduce the trial-error period in potential surgical candidates, provide solid biomarkers for monitoring the disease and identifying treatment responders. A clearer understanding of brain pathology at the early stages of the disorder will help clinicians to develop better criteria for identifying patients who are at risk of secondary brain damage and for timely intervention that achieves seizure control.     

High-resolution 3T MR neurography of radial neuropathy

The radial nerve is a continuation of the posterior cord of the brachial plexus and one of the major nerves that provide motor and sensory innervations to the forearm. MR imaging evaluation of the radial nerve pathology has been described in scattered case reports. Current high-field MR scanners enable high resolution and high contrast imaging of the peripheral nerves. This article reviews the 3 Tesla magnetic resonance neurography imaging of radial nerve anatomy and various pathologies affecting it with relevant case examples.     

Functional dissociation of hippocampal mechanism during implicit learning based on the domain of associations

Traditionally, the medial temporal lobe (MTL) was linked to explicit or declarative memory in associative learning. However, recent studies have reported MTL involvement even when volunteers are not consciously aware of the learned contingencies. Therefore, the mechanism of the MTL-related learning process cannot be described sufficiently by the explicit/implicit distinction, and the underlying process in the MTL for associative learning needs a more functional characterization. A possible feature that would allow a functional specification also for implicit learning is the nature of the material that is learned. Given that implicit memory tasks often comprise a combination of perceptual and motor learning, we hypothesized that implicit learning of the perceptual but not the motor component entails MTL activation in these studies. To directly test this hypothesis, we designed a purely perceptual and a purely motor variant of the serial reaction time task. In two groups of human volunteers, behavioral results clearly showed that both variants were learned without awareness. Neuronal recordings using fMRI revealed that bilateral hippocampal activation was observed only for implicit learning of the perceptual sequence, not for the motor sequence. This dissociation clearly shows that the functional role of the hippocampus for learning is determined by the domain of the learned association and that the function of the medial temporal lobe system is the processing of contingencies between perceptual features regardless of the explicit or implicit nature of the ensuing memory.