scholarly journals Present and future of the labyrinth imaging: Focus on the use of T2-weighted and contrast-enhanced delayed FLAIR (1 h) sequences

2021 ◽  
pp. 1-9
Author(s):  
Francis Veillon ◽  
Sophie Riehm ◽  
Michael Eliezer ◽  
Aurélie Karch-Georges ◽  
Anne Charpiot ◽  
...  
Keyword(s):  
High Resolution ◽  
Inner Ear ◽  
Internal Auditory Canal ◽  
Motion Artifacts ◽  
Maximum Height ◽  
Gradient Echo ◽  
Membranous Labyrinth ◽  
3T Mri ◽  
Contrast Enhanced ◽  
Weighted Sequences

OBJECTIVE: Part of the recent progress in the labyrinth imaging has been made possible by the rise of contrast-free T2-weighted and delayed (1h) FLAIR sequences. The aim of this article is to review evidence for the use of these two sequences to image the inner ear, especially the posterior membranous labyrinth. MATERIAL AND METHODS: We analyzed MRI-based papers (2007–2020)using high-resolution T2-weighted or contrast-enhanced FLAIR (1h) sequences to image the inner ear. RESULTS: T2-weighted sequences (3T MRI)enabled the visualization of the posterior membranous labyrinth with good correlation when compared to corresponding histological slices.Significant progress has been made, especially in terms of scanning time, aiming at reducing it, in order to decrease motions artifacts. The saccule is visible on a 3T MRI without significant motion artifacts. Its shape is ovoid, with a maximum height and width of 1.6 and 1.4 mm, respectively. An enlarged saccule was observed in 84%of patients with unilateral Meniere’s disease, in 28%of patients with vestibular schwannomas (VS) and 47%of patients with intralabyrinthine schwannomas. VS obstructing the internal auditory canal caused a decrease of the perilymphatic signal (more moderate decrease in meningiomas) on T2 gradient-echo images. Contrast-enhanced FLAIR sequences are useful to image vestibular/facial neuritis and inflammatory inner ear diseases. CONCLUSION: Precise analysis of the posterior membranous labyrinth, in terms of size, shape and signal intensity, is possible on a 3T MRI using high-resolution gradient-echo T2-weighted sequences. Such sequences are an interesting add-on to delayed (4h30) FLAIR-based protocols for labyrinth imaging.

scholarly journals Sensory epithelia of the fish inner ear in 3D: studied with high-resolution contrast enhanced microCT

2013 ◽  
Vol 10 (1) ◽  
pp. 63 ◽  
Author(s):  
Tanja Schulz-Mirbach ◽  
Martin Heß ◽  
Brian D Metscher
Keyword(s):  
High Resolution ◽  
Inner Ear ◽  
Sensory Epithelia ◽  
Contrast Enhanced

scholarly journals The Membranous Labyrinth in vivo from high-resolution Temporal CT data

2018 ◽  
Author(s):  
Hisaya Tanioka
Keyword(s):  
High Resolution ◽  
Inner Ear ◽  
Human Subjects ◽  
Membranous Labyrinth ◽  
3D Images ◽  
Temporal Bone Ct ◽  
Normal Human ◽  
Ct Data ◽  
Good Agreement

A prerequisite for the modeling and understanding of the inner ear mechanics needs the accurate created membranous labyrinth. I present a semi-automated methodology for accurate reconstruction of the membranous labyrinth in vivo from high-resolution temporal bone CT data of normal human subjects. I created the new technique which was combined with the segmentation methodology, transparent, thresholding, and opacity curve algorithms. This technique allowed the simultaneous multiple image creating without any overlapping regions in the inner ear has been developed. The reconstructed 3D images improved the membranous labyrinth geometry to realistically represent physiologic dimensions. These generated membranous structures were in good agreement with the published ones, while this approach was the most realistic in terms of the membranous labyrinth. The precise volume rendering depends on proprietary algorithms so that different results can be obtained, and the images appear qualitatively different. For each anatomical question, a different visualization technique should be used to obtain an optimal result. All scientists can create the membranous labyrinth in vivo in real time like a retinal camera.

scholarly journals Cochlear Nerve Canal Stenosis: Association With MYH14 and MYH9 Genes

2021 ◽  
pp. 014556132199683
Author(s):  
Wenqi Liang ◽  
Line Wang ◽  
Xinyu Song ◽  
Fenqi Gao ◽  
Pan Liu ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Next Generation Sequencing ◽  
Inner Ear ◽  
Internal Auditory Canal ◽  
Cochlear Nerve ◽  
Transverse Diameter ◽  
Congenital Hearing Loss ◽  
Canal Stenosis ◽  
Ear Anomalies ◽  
Generation Sequencing

The bony cochlear nerve canal transmits the cochlear nerve as it passes from the fundus of the internal auditory canal to the cochlea. Stenosis of the cochlear nerve canal, defined as a diameter less than 1.0 mm in transverse diameter, is associated with inner ear anomalies and severe to profound congenital hearing loss. We describe an 11-month-old infant with nonsyndromic congenital sensorineural hearing loss with cochlear nerve canal stenosis. Next-generation sequencing revealed heterozygous mutations in MYH9 and MYH14, encoding for the inner ear proteins myosin heavy chain IIA and IIC. The patient’s hearing was rehabilitated with bilateral cochlear implantation.

scholarly journals BIMG-04. MAPPING HETEROGENEITY OF HIGH-GRADE GLIOMA METABOLISM USING HIGH RESOLUTION 7T MRSI

2021 ◽  
Vol 3 (Supplement_1) ◽  
pp. i1-i1
Author(s):  
Gilbert Hangel ◽  
Cornelius Cadrien ◽  
Philipp Lazen ◽  
Sukrit Sharma ◽  
Julia Furtner ◽  
...  
Keyword(s):  
High Resolution ◽  
Imaging Techniques ◽  
Basis Set ◽  
Metabolic Imaging ◽  
Tumor Segmentation ◽  
Low Grade ◽  
High Grade ◽  
Isotropic Resolution ◽  
Contrast Enhanced ◽  
Definition Of

Abstract OBJECTIVES Neurosurgical resection in gliomas depends on the precise preoperative definition of the tumor and its margins to realize a safe maximum resection that translates into a better patient outcome. New metabolic imaging techniques could improve this delineation as well as designate targets for biopsies. We validated the performance of our fast high-resolution whole-brain 3D-magnetic resonance spectroscopic imaging (MRSI) method at 7T in high-grade gliomas (HGGs) as first step to this regard. METHODS We measured 23 patients with HGGs at 7T with MRSI covering the whole cerebrum with 3.4mm isotropic resolution in 15 min. Quantification used a basis-set of 17 neurochemical components. They were evaluated for their reliability/quality and compared to neuroradiologically segmented tumor regions-of-interest (necrosis, contrast-enhanced, non-contrast-enhanced+edema, peritumoral) and histopathology (e.g., grade, IDH-status). RESULTS We found 18/23 measurements to be usable and ten neurochemicals quantified with acceptable quality. The most common denominators were increases of glutamine, glycine, and total choline as well as decreases of N-acetyl-aspartate and total creatine over most tumor regions. Other metabolites like taurine and serine showed mixed behavior. We further found that heterogeneity in the metabolic images often continued into the peritumoral region. While 2-hydroxy-glutarate could not be satisfyingly quantified, we found a tendency for a decrease of glutamate in IDH1-mutant HGGs. DISCUSSION Our findings corresponded well to clinical tumor segmentation but were more heterogeneous and often extended into the peritumoral region. Our results corresponded to previous knowledge, but with previously not feasible resolution. Apart from glycine/glutamine and their role in glioma progression, more research on the connection of glutamate and others to specific mutations is necessary. The addition of low-grade gliomas and statistical ROI analysis in a larger cohort will be the next important steps to define the benefits of our 7T MRSI approach for the definition of spatial metabolic tumor profiles.

scholarly journals Utilizing SENSE to reduce scan duration in high-resolution contrast-enhanced renal MR angiography

2006 ◽  
Vol 24 (4) ◽  
pp. 873-879 ◽  
Author(s):  
Gregory J. Wilson ◽  
William B. Eubank ◽  
G. Boudewijn C. Vasbinder ◽  
Alfons G.H. Kessels ◽  
Romhild M. Hoogeveen ◽  
...  
Keyword(s):  
High Resolution ◽  
Mr Angiography ◽  
Contrast Enhanced
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