Feasibility of thin-slice, low noise images created using multi-kernel synthesis to replace multiple image series in head CT.

Background: SynthesiZed Improved Resolution and Concurrent nOise reductioN (ZIRCON) is a multi-kernel synthesis method that creates a single series of thin-slice computed tomography (CT) images displaying low noise and high spatial resolution, increasing reader efficiency and minimizing partial volume averaging.

Purpose: To compare the diagnostic performance of a single set of ZIRCON images to two routine clinical image series using conventional CT head and bone reconstruction kernels for diagnosing intracranial findings and fractures in patients with trauma or suspected acute neurologic deficit.

Material And Methods: In total, 50 patients underwent clinically indicated head CT in the ER (15 normal, 35 abnormal cases).

Direct pseudomeningocele contrast injection for spinal CSF leak localization.

CT myelography has been traditionally used to evaluate post-operative paraspinal fluid collections to discern CSF leaking into a pseudomeningocele versus a contained seroma. Rather than performing a lumbar puncture and injecting intrathecal contrast for myelography, we present the first report of direct contrast injection into a post-operative paraspinal pseudomeningocele for CSF leak confirmation and localization. This is a simple procedure that has several advantages over a conventional CT myelogram for the evaluation of post-operative paraspinal fluid collections.

Detection and Mitigation of Neurovascular Uncoupling in Brain Gliomas.

Functional magnetic resonance imaging (fMRI) with blood oxygen level-dependent (BOLD) technique is useful for preoperative mapping of brain functional networks in tumor patients, providing reliable in vivo detection of eloquent cortex to help reduce the risk of postsurgical morbidity. BOLD task-based fMRI (tb-fMRI) is the most often used noninvasive method that can reliably map cortical networks, including those associated with sensorimotor, language, and visual functions. BOLD resting-state fMRI (rs-fMRI) is emerging as a promising ancillary tool for visualization of diverse functional networks.

Pituitary volume changes in pregnancy and the post-partum period.

Purpose: Imaging changes in the pituitary volume during pregnancy remains scantly researched. This study set out to assess the differences in total, anterior, and posterior pituitary volume in pregnant women compared to nulliparous and post-partum women.

Materials And Methods: A retrospective review was completed of women that had undergone MRI imaging of the brain.

Manifestations of radiation toxicity in the head, neck, and spine: An image-based review.

Background And Purpose: Radiation therapy is an important component of treatment in patients with malignancies of the head, neck, and spine. However, radiation to these regions has well-known potential side effects, many of which can be encountered on imaging. In this manuscript, we review selected radiographic manifestations of therapeutic radiation to the head, neck, and spine that may be encountered in the practice of radiology.

Survival outcomes in locally advanced cutaneous squamous cell carcinoma presenting with clinical perineural invasion alone.

Background: Cutaneous squamous cell carcinomas (CSCC) involving the head and neck are common, but initial presentation or recurrence limited to the cranial nerves is rare.

Methods: We conducted a retrospective study of 21 patients with clinical perineural invasion (PNI) from CSCC and no measurable disease by RECIST 1.1.

Intracranial long-term complications of radiation therapy: an image-based review.

Background And Purpose: Radiation therapy is commonly utilized in the majority of solid cancers and many hematologic malignancies and other disorders. While it has an undeniably major role in improving cancer survival, radiation therapy has long been recognized to have various negative effects, ranging from mild to severe. In this manuscript, we review several intracranial manifestations of therapeutic radiation, with particular attention to those that may be encountered by radiologists.

Higher temporal resolution multiband fMRI provides improved presurgical language maps.

Purpose: We investigated the hypothesis that increasing fMRI temporal resolution using a multiband (MB) gradient echo-echo planar imaging (GRE-EPI) pulse sequence provides fMRI language maps of higher statistical quality than those acquired with a traditional GRE-EPI sequence.

Methods: This prospective study enrolled 29 consecutive patients receiving language fMRI prior to a potential brain resection for tumor, AVM, or epilepsy. A 4-min rhyming task was performed at 3.

Bilateral facial nerve involvement in a patient with Tolosa-Hunt syndrome.

Tolosa-Hunt syndrome is characterized by unilateral retro-orbital headaches and cranial nerve palsies, usually involving cranial nerves III-VI. It is rare for other cranial nerves to be involved, although this has previously been reported. We report a 19-year-old woman presenting with typical features of Tolosa-Hunt syndrome but ultimately developing bilateral facial nerve palsies and enhancement of both facial nerves on magnetic resonance imaging.

Intracranial Epidural Abscess in a 9-Year-Old Boy With Precocious Puberty and Use of Continuous Positive Airway Pressure.

Intracranial extension of rhinosinusitis is rare in children. We report a 9-year-old immunocompetent boy with central precocious puberty and obstructive sleep apnea-hypopnea syndrome who developed an intracranial epidural abscess secondary to rhinosinusitis while on continuous positive airway pressure (CPAP) treatment. A retrospective review of the medical record and imaging studies was performed.

Cranial Base Manifestations of Granulomatosis with Polyangiitis.

Objective: Although granulomatosis with polyangiitis (GPA; Wegener's granulomatosis) is classically characterized by systemic disease involving the kidneys and airway, approximately 10% of patients who have it present with isolated central nervous system disease. When involving the skull base, GPA frequently mimics more common pathology, resulting in diagnostic challenges and delay. The primary objective of this study is to characterize the cranial base manifestations of GPA, highlighting aspects most relevant to the skull base surgeon.

Current concepts of cross-sectional and functional anatomy of the cerebellum: a pictorial review and atlas.

Recognition of key concepts of structural and functional anatomy of the cerebellum can facilitate image interpretation and clinical correlation. Recently, the human brain mapping literature has increased our understanding of cerebellar anatomy, function, connectivity with the cerebrum, and significance of lesions involving specific areas.Both the common names and numerically based Schmahmann classifications of cerebellar lobules are illustrated.

Dose Reduction for Sinus and Temporal Bone Imaging Using Photon-Counting Detector CT With an Additional Tin Filter.

Objective: The aim of this study was to quantitatively demonstrate radiation dose reduction for sinus and temporal bone examinations using high-resolution photon-counting detector (PCD) computed tomography (CT) with an additional tin (Sn) filter.

Materials And Methods: A multienergy CT phantom, an anthropomorphic head phantom, and a cadaver head were scanned on a research PCD-CT scanner using ultra-high-resolution mode at 100-kV tube potential with an additional tin filter (Sn-100 kV) and volume CT dose index of 10 mGy. They were also scanned on a commercial CT scanner with an energy-integrating detector (EID) following standard clinical protocols.

CT angiogram findings in carotid-cavernous fistulas: stratification of imaging features to help radiologists avoid misdiagnosis.

Background: Carotid-cavernous fistulas (CCFs) are commonly misdiagnosed on computed tomography angiography (CTA).

Purpose: This study sought to identify the most sensitive and specific imaging features of CCFs on CTA.

Material And Methods: A retrospective review identified 18 consecutive patients suspected of having a CCF on CTA and subsequently underwent digital subtraction angiography (DSA).

Clinical Assessment of Metal Artifact Reduction Methods in Dual-Energy CT Examinations of Instrumented Spines.

Objective: The purpose of this study was to evaluate the performance of three metal artifact reduction methods in dual-energy CT (DECT) examinations of instrumented spines.

Materials And Methods: Twenty patients with instrumented spines who underwent spine DECT were retrospectively identified. All scans were obtained on a dual-source 128-MDCT scanner.

Evaluation of projection- and dual-energy-based methods for metal artifact reduction in CT using a phantom study.

Objectives: Both projection and dual-energy (DE)-based methods have been used for metal artifact reduction (MAR) in CT. The two methods can also be combined. The purpose of this work was to evaluate these three MAR methods using phantom experiments for five types of metal implants.

CT Dental Artifact: Comparison of an Iterative Metal Artifact Reduction Technique with Weighted Filtered Back-Projection.

Background: Dental hardware produces streak artifacts on computed tomography (CT) images reconstructed with the standard weighted filtered back projection (wFBP) method.

Purpose: To perform a preliminary evaluation of an iterative metal artifact reduction (IMAR) technique to assess its ability to improve anatomic visualization over wFBP in patients with dental amalgam or other hardware.

Material And Methods: CT images from patients with dental hardware were reconstructed using wFBP and IMAR software and soft-tissue or bone window/level settings.

Estimation of Observer Performance for Reduced Radiation Dose Levels in CT: Eliminating Reduced Dose Levels That Are Too Low Is the First Step.

Rationale And Objectives: This study aims to estimate observer performance for a range of dose levels for common computed tomography (CT) examinations (detection of liver metastases or pulmonary nodules, and cause of neurologic deficit) to prioritize noninferior dose levels for further analysis.

Materials And Methods: Using CT data from 131 examinations (abdominal CT, 44; chest CT, 44; head CT, 43), CT images corresponding to 4%-100% of the routine clinical dose were reconstructed with filtered back projection or iterative reconstruction. Radiologists evaluated CT images, marking specified targets, providing confidence scores, and grading image quality.

A robust noise reduction technique for time resolved CT.

Purpose: To develop a noise reduction method for time resolved CT data, especially those with significant patient motion.

Methods: PArtial TEmporal Nonlocal (PATEN) means is a technique that uses the redundant information in time-resolved CT data to achieve noise reduction. In this method, partial temporal profiles are used to determine the similarity (or weight) between pixels, and the similarity search makes use of both spatial and temporal information, providing robustness to patient motion.

Retrospective Analysis of Interobserver Spatial Variability in the Localization of Broca's and Wernicke's Areas Using Three Different fMRI Language Paradigms.

Purpose: To determine interobserver spatial variability in language area localization using three commonly employed language tasks.

Materials And Methods: With institutional review board approval, 125 fMRI time series from 50 different clinical language cases were retrospectively reviewed by three blinded readers who selected 3-dimensional points representing the perceived center of Wernicke's and Broca's areas using three language tasks (semantic decision, SD; sentence comprehension, SC; and silent word generation, WG). Point dispersion values were then calculated using the perimeter of the 3-dimensional triangle defined by the three readers' selections.

Is autogenous abdominal fat transplantation into a large temporomandibular joint defect following removal of failed alloplastic prosthesis a definitive treatment?

Purpose: To evaluate the long-term clinical outcome after the removal of failed major alloplastic temporomandibular joint (TMJ) implants and the placement of an autologous abdominal fat graft.

Materials And Methods: A long-term clinical follow-up was performed in 4 patients who underwent removal of a failed alloplastic implant and insertion of an autologous abdominal fat graft under 1-stage surgical management. Postsurgical use of pain medication was documented and the vertical interincisal opening measurement was obtained at the follow-up visit.

Progressive multifocal leukoencephalopathy: a rare infectious complication following allogeneic hematopoietic cell transplantation (HCT).

Progressive multifocal leukoencephalopathy (PML), a demyelinating disorder caused by brain infection with JC virus, is a neurological complication of immunocompromised states and immunosuppressive therapies. While most commonly seen in the HIV/AIDS population, patients with hematologic malignancies are also at risk following treatment protocols including monoclonal antibodies such as rituximab and after hematopoietic stem cell transplantation. Here, we present the case of PML following allogeneic HCT that highlights potential diagnostic difficulties.