Comparison of image quality between a novel mobile CT scanner and current generation stationary CT scanners.

Purpose: Point-of-care imaging with mobile CT scanners offers several advantages, provided that the image quality is satisfactory. Our aim was to compare image quality of a novel mobile CT to stationary scanners for patients in a neurosurgical intensive care unit (ICU).

Methods: From November 2020 to April 2021, all patients above 18 years of age examined by a mobile CT scanner at a neurosurgical ICU were included if they also had a stationary head CT examination during the same hospitalization.

The potential role of T2*-weighted multi-echo data image combination as an imaging marker for intraplaque hemorrhage in carotid plaque imaging.

Background: Carotid atherosclerotic plaques with intraplaque hemorrhage (IPH) are associated with elevated stroke risk. IPH is predominantly imaged based on paramagnetic properties of the upstream hemoglobin degradation product methemoglobin. This is an explorative observational study to test the feasibility of a spoiled gradient echo based T2* weighted MRI sequence (3D MEDIC) for carotid plaque imaging, and to compare signs suggestive of the downstream degradation product hemosiderin on 3D MEDIC with signs of methemoglobin on a T1wBB sequence.

Classifications of atherosclerotic plaque components with T1 and T2* mapping in 11.7 T MRI.

Background And Aims: Histopathology is the gold standard for analysis of atherosclerotic plaques but has drawbacks due to the destructive nature of the method. MRI is a non-destructive method to image whole plaques. Our aim was to use quantitative high field MRI to classify plaque components, with histology as gold standard.

Can iterative reconstruction algorithms replace tube loading compensation in low kVp hepatic CT? Subjective versus objective image quality.

Background: Hepatic computed tomography (CT) with decreased peak kilovoltage (kVp) may be used to reduce contrast medium doses in patients at risk of contrast-induced acute kidney injury (CI-AKI); however, it increases image noise. To preserve image quality, noise has been controlled by X-ray tube loading (mAs) compensation (TLC), i.e.

Head computed tomography for prognostication of poor outcome in comatose patients after cardiac arrest and targeted temperature management.

Introduction: A multimodal approach to prognostication of outcome after cardiac arrest (CA) is recommended. Evidence for combinations of methods is low. In this post-hoc analysis we described findings on head computed tomography (CT) after CA.

Imaging of the Lungs in Organ Donors and its Clinical Relevance: A Retrospective Analysis.

Purpose: The aim of the study was to retrospectively evaluate the diagnostic imaging that potential lung donors undergo, the reader variability of image interpretation and its relevance for donation, and the potential information gained from imaging studies not primarily intended for lung evaluation but partially including them.

Materials And Methods: Bedside chest radiography and computed tomography (CT), completely or incompletely including the lungs, of 110 brain-dead potential organ donors in a single institution during 2007 to 2014 were reviewed from a donation perspective. Two chest radiologists in consensus analyzed catheters and cardiovascular, parenchymal, and pleural findings.

Reduced Quality of Life in Patients with Pituitary Dysfunction After Aneurysmal Subarachnoid Hemorrhage: A Prospective Longitudinal Study.

Objective: Pituitary dysfunction (PD) after aneurysmal subarachnoid hemorrhage (SAH) has been demonstrated in several studies. Given the similarities between psychological symptoms and reduced quality of life (QoL) in patients with PD and fatigue commonly seen in patients after SAH, we investigated the relationship between QoL and PD after SAH.

Methods: There were 51 patients with aneurysmal SAH prospectively recruited and evaluated for health-related QoL using the Psychological General Well-Being Index.

Impact of iterative reconstructions on image noise and low-contrast object detection in low kVp simulated abdominal CT: a phantom study.

Background: Low kilovoltage (kVp) computed tomography (CT) may be used to reduce contrast medium dose in patients at risk of contrast nephropathy, at the cost of increased image noise.

Purpose: To evaluate: (i) the impact of iterative reconstructions (Siemens SAFIRE) on low-contrast object detection to compensate for increased noise instead of increased tube loading when decreasing tube potential; and (ii) the change in iodine attenuation in simulated abdominal CT.

Material And Methods: A phantom was scanned at 70, 80, 100, and 120 kVp at fixed effective tube loading (170 mAsEFF) and fixed radiation dose (CTDIVOL 10 mGy).

Blood-brain barrier permeability following traumatic brain injury.

Background: Brain edema and intracranial hypertension is deleterious after traumatic brain injury (TBI), but the underlying pathophysiology is complex and poorly understood. One major subject of controversy is the time course and extent of blood-brain barrier (BBB) dysfunction following trauma, and previous studies in humans have only provided semi-quantitative data. The objective of the present study was therefore to quantify changes in BBB-permeability in the early course of TBI, when brain edema is still evolving.

Circulation stabilizing therapy and pulmonary high-resolution computed tomography in a porcine brain-dead model.

Background: Currently 80% of donor lungs are not accepted for transplantation, often due to fluid overload. Our aim was to investigate if forced fluid infusion may be replaced by a new pharmacological therapy to stabilize circulation after brain death in an animal model, and to assess therapy effects on lung function and morphology trough blood gas parameters and state-of-the-art High-resolution CT (HRCT).

Methods: Brain death was caused by surgical decapitation.

CT angiography in non-traumatic subarachnoid hemorrhage: the importance of arterial attenuation for the detection of intracranial aneurysms.

Background: Computed tomography angiography (CTA) is today the primary method for the detection of intracranial aneurysms. The technique has evolved considerably during the last decade, and it is important to establish criteria for high image quality, especially with regard to improving the diagnosis of small aneurysms.

Purpose: To evaluate diagnostic accuracy and image quality by arterial attenuation of CTA in patients with non-traumatic subarachnoid hemorrhage (SAH).

How to image patients with spine pain.

Different radiological methods play an important role in the work-up of patients complaining of spine pain. Depending on the symptoms and the suspected underlying etiology different methods are selected. In the following presentation we briefly present the different radiological and magnetic resonance tomography methods that are at hand, give some guidance in which method to use, and present the typical imaging findings in some of the most common conditions that presents with spine pain.

Hybrid iterative reconstruction algorithm improves image quality in craniocervical CT angiography.

Objective: The purpose of this study was to evaluate the potential of a hybrid iterative reconstruction algorithm for improving image quality in craniocervical CT angiography (CTA) and to assess observer performance.

Subjects And Methods: Thirty patients (mean age, 58 years; range 16-80 years) underwent standard craniocervical CTA (volume CT dose index, 6.8 mGy, 2.

Emergency room decision-making for urgent cranial computed tomography: selection criteria for subsets of non-trauma patients.

Background: Computed tomography (CT) of the brain is used extensively in the urgent work-up of patients with a suspicion of intracranial pathology, but is often normal. Previously proposed selection criteria aim at limiting the ordering of urgent cranial CT in the non-trauma population, while maintaining high sensitivity for diagnoses demanding immediate attention.

Purpose: To retrospectively evaluate these selection criteria in a general non-trauma population from a Swedish tertiary hospital, as well as in a nested subgroup that lacks guidelines at present, namely where the chief complaint was not headache, symptoms clearly indicating stroke, seizures, or vertigo.

Six iterative reconstruction algorithms in brain CT: a phantom study on image quality at different radiation dose levels.

Objective: To evaluate the image quality produced by six different iterative reconstruction (IR) algorithms in four CT systems in the setting of brain CT, using different radiation dose levels and iterative image optimisation levels.

Methods: An image quality phantom, supplied with a bone mimicking annulus, was examined using four CT systems from different vendors and four radiation dose levels. Acquisitions were reconstructed using conventional filtered back-projection (FBP), three levels of statistical IR and, when available, a model-based IR algorithm.

Hybrid iterative reconstruction algorithm in brain CT: a radiation dose reduction and image quality assessment study.

Background: Iterative reconstruction (IR) algorithms improve image quality and allow for radiation dose reduction in CT. Dose reduction is particularly challenging in brain CT where good low-contrast resolution is essential. Ideally, evaluation of image quality combines objective measurements and subjective assessment of clinically relevant quality criteria.

CT angiography of intracranial arterial vessels: impact of tube voltage and contrast media concentration on image quality.

Background: Computed tomography angiography (CTA) of intracranial arteries has high demands on image quality. Important parameters influencing vessel enhancement are injection rate, concentration of contrast media and tube voltage.

Purpose: To evaluate the impact of an increase of contrast media concentration from 300 to 400 mg iodine/mL (mgI/mL) and the effect of a decrease of tube voltage from 120 to 90 kVp on vessel attenuation and image quality in CT angiography of intracranial arteries.

Method for studying gas composition in the human mastoid cavity by use of laser spectroscopy.

Objectives: We evaluated a method for gas monitoring in the mastoid cavity using tunable diode laser spectroscopy by comparing it to simultaneously obtained computed tomographic (CT) scans.

Methods: The presented optical technique measures free gases, oxygen (O2), and water vapor (H2O) within human tissue by use of low-power diode lasers. Laser light was sent into the tip of the mastoid process, and the emerging light at the level of the antrum was captured with a detector placed on the skin.

Radiation dose reduction in CT of the brain: can advanced noise filtering compensate for loss of image quality?

Background: Computed tomography (CT) of the brain is performed with high local doses due to high demands on low contrast resolution. Advanced algorithms for noise reduction might be able to preserve critical image information when reducing radiation dose.

Purpose: To evaluate the effect of advanced noise filtering on image quality in brain CT acquired with reduced radiation dose.

Non-invasive diagnostics of the maxillary and frontal sinuses based on diode laser gas spectroscopy.

Problem: Suspected, but objectively absent, rhinosinusitis constitutes a major cause of visits to the doctor, high health care costs, and the over-prescription of antibiotics, contributing to the serious problem of resistant bacteria. This situation is largely due to a lack of reliable and widely applicable diagnostic methods.

Method: A novel method for the diagnosis of rhinosinusitis based on non-intrusive diode laser gas spectroscopy is presented.

Neuron-specific enolase correlates with other prognostic markers after cardiac arrest.

Objective: Therapeutic hypothermia (TH) is a recommended treatment for survivors of cardiac arrest. Prognostication is complicated since sedation and muscle relaxation are used and established indicators of a poor prognosis are lacking. This prospective, observational study describes the pattern of commonly used prognostic markers in a hypothermia-treated cohort of cardiac arrest patients with prolonged coma.

Comprehensive CT Evaluation in Acute Ischemic Stroke: Impact on Diagnosis and Treatment Decisions.

Background. With modern CT imaging a comprehensive overview of cerebral macro- and microcirculation can be obtained within minutes in acute ischemic stroke. This opens for patient stratification and individualized treatment.

Correlation between arterial blood volume obtained by arterial spin labelling and cerebral blood volume in intracranial tumours.

Objective: To compare measurements of the arterial blood volume (aBV), a perfusion parameter calculated from arterial spin labelling (ASL), and cerebral blood volume (CBV), calculated from dynamic susceptibility contrast (DSC) MRI. In the clinic, CBV is used for grading of intracranial tumours.

Materials And Methods: Estimates of aBV from the model-free ASL technique quantitative STAR labelling of arterial regions (QUASAR) experiment and of DSC-CBV were obtained at 3T in ten patients with eleven tumours (three grade III gliomas, four glioblastomas and four meningiomas, two in one patient).