Evaluation of an Artificial Intelligence Model for Identification of Mass Effect and Vasogenic Edema on CT of the Head.

Background And Purpose: Mass effect and vasogenic edema are critical findings on CT of the head. This study compared the accuracy of an artificial intelligence model (Annalise Enterprise CTB) with consensus neuroradiologists' interpretations in detecting mass effect and vasogenic edema.

Materials And Methods: A retrospective stand-alone performance assessment was conducted on data sets of noncontrast CT head cases acquired between 2016 and 2022 for each finding.

Not without Context-A Multiple Methods Study on Evaluation and Correction of Automated Brain Tumor Segmentations by Experts.

Rationale And Objectives: Brain tumor segmentations are integral to the clinical management of patients with glioblastoma, the deadliest primary brain tumor in adults. The manual delineation of tumors is time-consuming and highly provider-dependent. These two problems must be addressed by introducing automated, deep-learning-based segmentation tools.

Incorporating algorithmic uncertainty into a clinical machine deep learning algorithm for urgent head CTs.

Machine learning (ML) algorithms to detect critical findings on head CTs may expedite patient management. Most ML algorithms for diagnostic imaging analysis utilize dichotomous classifications to determine whether a specific abnormality is present. However, imaging findings may be indeterminate, and algorithmic inferences may have substantial uncertainty.

The "Crossing Collection Sign": A Diagnostic Tool on Spine Magnetic Resonance Imaging For Localizing Cerebrospinal Fluid Leak.

Objective: The aim of the study is to determine whether the site of "cross" between ventral and dorsal spinal longitudinal extradural CSF collections (SLECs) seen on magnetic resonance imaging during initial workup of patients with suspected CSF leaks can predict the subsequently confirmed leakage site on computed tomography myelography or surgical repair.

Methods: This was an institutional review board-approved, retrospective study performed from 2006 to 2021. Patients with SLECs who underwent total spine magnetic resonance imaging at our institution, followed by myelography and/or surgical repair for CSF leak, were included.

Head CT deep learning model is highly accurate for early infarct estimation.

Non-contrast head CT (NCCT) is extremely insensitive for early (< 3-6 h) acute infarct identification. We developed a deep learning model that detects and delineates suspected early acute infarcts on NCCT, using diffusion MRI as ground truth (3566 NCCT/MRI training patient pairs). The model substantially outperformed 3 expert neuroradiologists on a test set of 150 CT scans of patients who were potential candidates for thrombectomy (60 stroke-negative, 90 stroke-positive middle cerebral artery territory only infarcts), with sensitivity 96% (specificity 72%) for the model versus 61-66% (specificity 90-92%) for the experts; model infarct volume estimates also strongly correlated with those of diffusion MRI (r > 0.

Development and clinical application of a deep learning model to identify acute infarct on magnetic resonance imaging.

Stroke is a leading cause of death and disability. The ability to quickly identify the presence of acute infarct and quantify the volume on magnetic resonance imaging (MRI) has important treatment implications. We developed a machine learning model that used the apparent diffusion coefficient and diffusion weighted imaging series.

The Composite Severity Score for Lumbar Spine MRI: a Metric of Cumulative Degenerative Disease Predicts Time Spent on Interpretation and Reporting.

Conventional measures of radiologist efficiency, such as the relative value unit, fail to account for variations in the complexity and difficulty of a given study. For lumbar spine MRI (LMRI), an ideal performance metric should account for the global severity of lumbar degenerative disease (LSDD) which may influence reporting time (RT), thereby affecting clinical productivity. This study aims to derive a global LSDD metric and estimate its effect on RT.

Effects of age and sex on the distribution and symmetry of lumbar spinal and neural foraminal stenosis: a natural language processing analysis of 43,255 lumbar MRI reports.

Purpose: The purpose of this study is to investigate relationship of patient age and sex to patterns of degenerative spinal stenosis on lumbar MRI (LMRI), rated as moderate or greater by a spine radiologist, using natural language processing (NLP) tools.

Methods: In this retrospective, IRB-approved study, LMRI reports acquired from 2007 to 2017 at a single institution were parsed with a rules-based natural language processing (NLP) algorithm for free-text descriptors of spinal canal stenosis (SCS) and neural foraminal stenosis (NFS) at each of six spinal levels (T12-S1) and categorized according to a 6-point grading scale. Demographic differences in the anatomic distribution of moderate (grade 3) or greater SCS and NFS were calculated by sex, and age and within-group differences for NFS symmetry (left vs.

Lumbar MRI Reporting Efficiency for Trainees Over the Academic Year: An Opportunity for Improving Clinical Workflows in Academic Medical Centers.

Purpose: Reporting efficiency is commonly used to measure performance and quality in diagnostic imaging. For academic centers, balancing the clinical demand for efficient reporting and educational obligation to trainees remains a major challenge. The objective of this study was to quantify the effect of trainee education on reporting efficiency over the academic year (July to June) for a single diagnostic imaging examination type.

An explainable deep-learning algorithm for the detection of acute intracranial haemorrhage from small datasets.

Owing to improvements in image recognition via deep learning, machine-learning algorithms could eventually be applied to automated medical diagnoses that can guide clinical decision-making. However, these algorithms remain a 'black box' in terms of how they generate the predictions from the input data. Also, high-performance deep learning requires large, high-quality training datasets.

Wide Range of Clinical Outcomes in Patients with Gliomatosis Cerebri Growth Pattern: A Clinical, Radiographic, and Histopathologic Study.

Background: The 2016 World Health Organization Classification of Central Nervous System Tumors categorizes gliomatosis cerebri growth pattern (GC) as a subgroup of diffuse infiltrating gliomas, defined by extent of brain involvement on magnetic resonance imaging (MRI). Clinical and radiographic features in GC patients are highly heterogeneous; however, prognosis has historically been considered poor.

Subjects, Materials, And Methods: We performed a retrospective search for patients at our institution meeting radiographic criteria of primary, type I GC (defined as diffuse tumor infiltration without associated tumor mass and contrast enhancement on MRI) and analyzed their clinical, imaging, and histopathologic features.

Dual-Energy Computed Tomography Angiography of the Head and Neck and Related Applications.

Dual-energy computed tomography (DECT) has become an increasingly widespread and useful component of the neuroimaging armamentarium, offering automated bone removal, metallic artifact reduction, and improved characterization of iodinated contrast enhancement. The application of these techniques to CT neuroangiography enables a number of benefits including more efficient 3D post-processing, contrast dose reduction opportunities, successful differentiation of hemorrhage from contrast staining following thromboembolic recanalization therapy, improved detection of active contrast extravasation in the setting of intracranial hemorrhage, and more precise characterization of atheromatous steno-occlusive disease.

Long-term outcomes of percutaneous lumbar facet synovial cyst rupture.

Objective: To evaluate the therapeutic value, safety, and long-term clinical outcomes of percutaneous lumbar facet synovial cyst (LFSC) rupture.

Materials And Methods: Our study was institutional review board (IRB)-approved and Health Insurance Portability and Accountability Act (HIPAA)-compliant. The study group comprised 71 patients (44 women, mean age: 65 ± 17 years) who underwent CT- or fluoroscopy-guided percutaneous LFSC rupture.

Myelography: modern technique and indications.

Myelography describes the instillation of intrathecal contrast media for the imaging evaluation of spinal canal pathology. The technique has evolved with the use of progressively less toxic contrast agents over its 90-year history and the inclusion of advanced image acquisition technology, including both computed tomography (CT) and magnetic resonance imaging (MRI), in addition to plain radiographic projections. The use of myelography for routine evaluation of spinal disease has diminished greatly due to the advent of MRI which has superior soft-tissue contrast and is relatively non-invasive.

Dual-Energy Head CT Enables Accurate Distinction of Intraparenchymal Hemorrhage from Calcification in Emergency Department Patients.

Purpose To evaluate the ability of dual-energy (DE) computed tomography (CT) to differentiate calcification from acute hemorrhage in the emergency department setting. Materials and Methods In this institutional review board-approved study, all unenhanced DE head CT examinations that were performed in the emergency department in November and December 2014 were retrospectively reviewed. Simulated 120-kVp single-energy CT images were derived from the DE CT acquisition via postprocessing.

Rate of Contrast Extravasation on Computed Tomographic Angiography Predicts Hematoma Expansion and Mortality in Primary Intracerebral Hemorrhage.

Background And Purpose: In primary intracerebral hemorrhage, the presence of contrast extravasation after computed tomographic angiography (CTA), termed the spot sign, predicts hematoma expansion and mortality. Because the biological underpinnings of the spot sign are not fully understood, we investigated whether the rate of contrast extravasation, which may reflect the rate of bleeding, predicts expansion and mortality beyond the simple presence of the spot sign.

Methods: Consecutive intracerebral hemorrhage patients with first-pass CTA followed by a 90-second delayed postcontrast CT (delayed CTA) were included.

Optimal brain MRI protocol for new neurological complaint.

Background/purpose: Patients with neurologic complaints are imaged with MRI protocols that may include many pulse sequences. It has not been documented which sequences are essential. We assessed the diagnostic accuracy of a limited number of sequences in patients with new neurologic complaints.

Spot sign on 90-second delayed computed tomography angiography improves sensitivity for hematoma expansion and mortality: prospective study.

Background And Purpose: The computed tomography angiography (CTA) spot sign is a validated biomarker for poor outcome and hematoma expansion in intracerebral hemorrhage. The spot sign has proven to be a dynamic entity, with multimodal imaging proving to be of additional value. We investigated whether the addition of a 90-second delayed CTA acquisition would capture additional intracerebral hemorrhage patients with the spot sign and increase the sensitivity of the spot sign.

Emergency department CT screening of patients with nontraumatic neurological symptoms referred to the posterior fossa: comparison of thin versus thick slice images.

Evaluation of the posterior fossa (PF) on 5-mm-thick helical CT images (current default) has improved diagnostic accuracy compared to 5-mm sequential CT images; however, 5-mm-thick images may not be ideal for PF pathology due to volume averaging of rapid changes in anatomy in the Z-direction. Therefore, we sought to determine if routine review of 1.25-mm-thin helical CT images has superior accuracy in screening for nontraumatic PF pathology.

Clot length distribution and predictors in anterior circulation stroke: implications for intra-arterial therapy.

Background And Purpose: Thin-section noncontrast computed tomography images can be used to measure hyperdense clot length in acute ischemic stroke. Clots≥8 mm have a very low probability of intravenous tissue-type plasminogen activator recanalization and hence may benefit from a bridging intra-arterial approach. To understand the prevalence of such clots, we sought to determine the distribution and predictors of clot lengths in consecutive anterior circulation proximal artery occlusions.

Using a web-based image quality assurance reporting system to improve image quality.

Objective: The purpose of this study is to show the impact of a web-based image quality assurance reporting system on the rates of three common image quality errors at our institution.

Materials And Methods: A web-based image quality assurance reporting system was developed and used beginning in April 2009. Image quality endpoints were assessed immediately before deployment (period 1), approximately 18 months after deployment of a prototype reporting system (period 2), and approximately 12 months after deployment of a subsequent upgraded department-wide reporting system (period 3).

Role of cardiac and extracranial vascular CT in the evaluation/management of cerebral ischemia and stroke.

Collectively, cardiac and large artery sources are responsible for the largest proportion of acute ischemic stroke. Technological advancements in computed tomography (CT) continue to improve evaluation of these patients. The literature was reviewed for the potential role and impact of these innovations in evaluation and management of these patients.

The Massachusetts General Hospital acute stroke imaging algorithm: an experience and evidence based approach.

The Massachusetts General Hospital Neuroradiology Division employed an experience and evidence based approach to develop a neuroimaging algorithm to best select patients with severe ischemic strokes caused by anterior circulation occlusions (ACOs) for intravenous tissue plasminogen activator and endovascular treatment. Methods found to be of value included the National Institutes of Health Stroke Scale (NIHSS), non-contrast CT, CT angiography (CTA) and diffusion MRI. Perfusion imaging by CT and MRI were found to be unnecessary for safe and effective triage of patients with severe ACOs.

Virtual monochromatic reconstruction of dual-energy unenhanced head CT at 65-75 keV maximizes image quality compared with conventional polychromatic CT.

Purpose: To determine the virtual monochromatic imaging (VMI) energy levels that maximize brain parenchymal image quality in dual-energy unenhanced head computed tomography (CT) and to assess the improvement with this technique compared with conventional polychromatic scanning.

Materials And Methods: Institutional review board approval was obtained with no informed consent required for this HIPAA-compliant retrospective analysis. Twenty-five consecutive unenhanced head CT scans were acquired with a 64-section dual-energy scanner with fast tube voltage switching (80-140 kVp).

Using Keynote to present radiology images.

Numerous articles have offered instructions for working with advanced radiology images in Microsoft PowerPoint (Redmond, WA); however, no articles have detailed instructions to do the same on alternative presentation software. Apple Macintosh (Cupertino, CA) computers are gaining popularity with many radiologists, due in part to the availability of a powerful, free, open-source Digital Imaging and Communications in Medicine (DICOM) viewing and manipulating software OsiriX ( http://www.osirix-viewer.