Advanced MR Imaging of the Temporal Bone

Comparison of Diagnostic Performance and Image Quality between Topup-Corrected and Standard Readout-Segmented Echo-Planar Diffusion-Weighted Imaging for Cholesteatoma Diagnostics

This study compares the diagnostic performance and image quality of single-shot turbo spin-echo DWI (tseDWI), standard readout-segmented DWI (rsDWI), and a modified rsDWI version (topupDWI) for cholesteatoma diagnostics. Thirty-four patients with newly suspected unilateral cholesteatoma were examined on a 1.5 Tesla MRI scanner. Diagnostic performance was evaluated by calculating and comparing the sensitivity and specificity using histopathological results as the standard of reference. Image quality was independently reviewed by two readers using a 5-point Likert scale evaluating image distortions, susceptibility artifacts, image resolution, lesion conspicuity, and diagnostic confidence. Twenty-five cholesteatomas were histologically confirmed after surgery and originated in the study group. TseDWI showed the highest sensitivity with 96% (95% confidence interval (CI): 88–100%), followed by topupDWI with 92% (95% CI: 81–100%) for both readers. The sensitivity for rsDWI was 76% (95% CI: 59–93%) for reader 1 and 84% (95% CI: 70–98%) for reader 2, respectively. Both tseDWI and topupDWI revealed a specificity of 100% (95% CI: 66–100%) and rsDWI of 89% (95% CI: 52–100%). Both tseDWI and topupDWI showed fewer image distortions and susceptibility artifacts compared to rsDWI. Image resolution was consistently rated best for topupDWI, followed by rsDWI, which both outperformed tseDWI. TopupDWI and tseDWI showed comparable results for lesions’ conspicuity and diagnostic confidence, both outperforming rsDWI. Modified readout-segmented DWI using the topup-correction method is preferable to standard rsDWI and may be regarded as an accurate alternative to single-shot turbo spin-echo DWI in cholesteatoma diagnostics.

Checklist for the evaluation of magnetic resonance imaging in otological pathology

Otolaryngology specialists must be familiar with radiological studies that allow the diagnosis of different otological pathologies. Magnetic resonance imaging is a complement to computed tomography, which allows a better evaluation of soft tissues and contributes to the differential diagnosis of space-occupying lesions located in the temporal bone and lateral skull base. It is also the technique of choice for the evaluation of the inner ear and the anatomical structures located in the cerebellopontine angle. In this article we present a checklist for magnetic resonance imaging of the ear with different sections that will allow a systematic review of all structures of interest in otological practice, as well as the preferred sequences for each situation.

Checklist for the evaluation of magnetic resonance imaging in otological pathology

Otolaryngology specialists must be familiar with radiological studies that allow the diagnosis of different otological pathologies. Magnetic resonance imaging is a complement to computed tomography, which allows a better evaluation of soft tissues and contributes to the differential diagnosis of space-occupying lesions located in the temporal bone and lateral skull base. It is also the technique of choice for the evaluation of the inner ear and the anatomical structures located in the cerebellopontine angle. In this article we present a checklist for magnetic resonance imaging of the ear with different sections that will allow a systematic review of all structures of interest in otological practice, as well as the preferred sequences for each situation.

Advanced Magnetic Resonance Imaging of the Skull Base

Magnetic resonance (MR) imaging is a crucial tool for evaluation of the skull base, enabling characterization of complex anatomy by utilizing multiple image contrasts. Recent technical MR advances have greatly enhanced radiologists' capability to diagnose skull base pathology and help direct management. In this paper, we will summarize cutting-edge clinical and emerging research MR techniques for the skull base, including high-resolution, phase-contrast, diffusion, perfusion, vascular, zero echo-time, elastography, spectroscopy, chemical exchange saturation transfer, PET/MR, ultra-high-field, and 3D visualization. For each imaging technique, we provide a high-level summary of underlying technical principles accompanied by relevant literature review and clinical imaging examples.

Neuroimaging in Children with Ophthalmological Complaints: A Review

Pediatric patients are commonly referred to imaging following abnormal ophthalmological examinations. Common indications include papilledema, altered vision, strabismus, nystagmus, anisocoria, proptosis, coloboma, and leukocoria. Magnetic resonance imaging (MRI) of the brain and orbits (with or without contrast material administration) is typically the imaging modality of choice. However, a cranial CT scan is sometimes initially performed, particularly when MRI is not readily available. Familiarity with the various ophthalmological conditions may assist the radiologist in formulating differential diagnoses and proper MRI protocols afterward. Although MRI of the brain and orbits usually suffices, further refinements are sometimes warranted to enable suitable assessment and accurate diagnosis. For example, the assessment of children with sudden onset anisocoria associated with Horner syndrome will require imaging of the entire oculosympathetic pathway, including the brain, orbits, neck, and chest. Dedicated orbital scans should cover the area between the hard palate and approximately 1 cm above the orbits in the axial plane and extend from the lens to the midpons in the coronal plane. Fat-suppressed T2-weighted fast spin echo sequences should enable proper assessment of the globes, optic nerves, and perioptic subarachnoid spaces. Contrast material should be given judiciously, ideally according to clinical circumstances and precontrast scans. In this review, we discuss the major indications for imaging following abnormal ophthalmological examinations.

Diffusion MR Imaging in the Head and Neck: Principles and Applications

Diffusion imaging is a functional MR imaging tool that creates tissue contrast representative of the random, microscopic translational motion of water molecules within human body tissues. Long considered a cornerstone MR imaging sequence for brain imaging, diffusion-weighted imaging (DWI) increasingly is used for head and neck imaging. This review reports the current state of diffusion techniques for head and neck imaging, including conventional DWI, DWI trace with apparent diffusion coefficient map, diffusion tensor imaging, intravoxel incoherent motion, and diffusion kurtosis imaging. This article describes background physics, reports supportive evidence and potential pitfalls, highlights technical advances, and details practical clinical applications.