Simpler and effective radiological evaluations for modiolar proximity of a slim modiolar cochlear implant electrode

Abstract A new slim modiolar electrode (CI532/632) has been reported to ensure better modiolar proximity than conventional electrodes. Better modiolar proximity has been proposed to yield better electrode discrimination capability and potentially better speech outcomes, necessitating its efficient measurement. Currently, intracochlear positional index (ICPI), the most reliable indicator for evaluating modiolar proximity, has been measured exclusively through ‘metal artifact-less’ cone beam CT. However, popular use of this index is precluded due to lack of cone beam CT in many institutions. Thus, eyes are now on elucidation of easy-to-measure indicators of modiolar proximity derived from conventional CT, which is accessible in all centers. We observed that enhanced tomographic resolution significantly reduces partial volume artifacts, providing better visualization of modiolus-electrode distance. Aided by ultra-high kernel specification with high-resolution index, we developed a novel and easy-to-measure, conventional CT-specific indicator, “modified ICPI”, for evaluation of modiolar proximity. Further, we showed that it closely correlates with the previously proposed parameter of modiolar proximity, the spiral diameter, measured from post-insertion radiograph, reiterating the value of X-ray-based spiral diameter. Through this study, we have taken a step toward the stage of immediate visual feedback regarding modiolar proximity and changes in insertion technique intraoperatively, ensuring optimal modiolar proximity.

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Achieving high-resolution soft-tissue imaging with cone-beam CT: a two-pronged approach for modulation of x-ray fluence and detector gain

10.1117/12.595886 ◽

2005 ◽

Cited By ~ 2

Author(s):

S. A. Graham ◽

J. H. Siewerdsen ◽

D. J. Moseley ◽

H. Keller ◽

N. A. Shkumat ◽

...

Keyword(s):

High Resolution ◽

Soft Tissue ◽

Cone Beam Ct ◽

Tissue Imaging ◽

Cone Beam ◽

X Ray

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3D cone-beam CT with a twin robotic x-ray system in elbow imaging: comparison of image quality to high-resolution multidetector CT

European Radiology Experimental ◽

10.1186/s41747-020-00177-y ◽

2020 ◽

Vol 4 (1) ◽

Author(s):

Jan-Peter Grunz ◽

Andreas Max Weng ◽

Andreas Steven Kunz ◽

Maike Veyhl-Wichmann ◽

Rainer Schmitt ◽

...

Keyword(s):

High Resolution ◽

Image Quality ◽

Multidetector Ct ◽

Cone Beam Ct ◽

Intraclass Correlation ◽

Cone Beam ◽

Single Measure ◽

X Ray ◽

Mdct Image ◽

Significant Difference

Abstract Background Elbow imaging is challenging with conventional multidetector computed tomography (MDCT), while cone-beam CT (CBCT) provides superior options. We compared intra-individually CBCT versus MDCT image quality in cadaveric elbows. Methods A twin robotic x-ray system with new CBCT mode and a high-resolution clinical MDCT were compared in 16 cadaveric elbows. Both systems were operated with a dedicated low-dose (LD) protocol (equivalent volume CT dose index [CTDIvol(16 cm)] = 3.3 mGy) and a regular clinical scan dose (RD) protocol (CTDIvol(16 cm) = 13.8 mGy). Image quality was evaluated by two radiologists (R1 and R2) on a seven-point Likert scale, and estimation of signal intensity in cancellous bone was conducted. Wilcoxon signed-rank tests and intraclass correlation coefficient (ICC) statistics were used. Results The CBCT prototype provided superior subjective image quality compared to MDCT scans (for RD, p ≤ 0.004; for LD, p ≤ 0.001). Image quality was rated very good or excellent in 100% of the cases by both readers for RD CBCT, 100% (R1) and 93.8% (R2) for LD CBCT, 62.6% and 43.8% for RD MDCT, and 0.0% and 0.0% for LD MDCT. Single-measure ICC was 0.95 (95% confidence interval 0.91–0.97; p < 0.001). Software-based assessment supported subjective findings with less “undecided” pixels in CBCT than dose-equivalent MDCT (p < 0.001). No significant difference was found between LD CBCT and RD MDCT. Conclusions In cadaveric elbow studies, the tested cone-beam CT prototype delivered superior image quality compared to high-end multidetector CT and showed a potential for considerable dose reduction.

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Prospective Randomized Trial for Image-Guided Biopsy Using Cone-Beam CT Navigation Compared with Conventional CT

Journal of Vascular and Interventional Radiology ◽

10.1016/j.jvir.2016.05.034 ◽

2016 ◽

Vol 27 (9) ◽

pp. 1342-1349 ◽

Cited By ~ 17

Author(s):

Nadine Abi-Jaoudeh ◽

Teresa Fisher ◽

John Jacobus ◽

Marlene Skopec ◽

Alessandro Radaelli ◽

...

Keyword(s):

Randomized Trial ◽

Cone Beam Ct ◽

Prospective Randomized Trial ◽

Cone Beam ◽

Image Guided ◽

Guided Biopsy ◽

Conventional Ct

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A Method to Improve Electron Density Measurement of Cone-Beam CT Using Dual Energy Technique

BioMed Research International ◽

10.1155/2015/858907 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Kuo Men ◽

Jian-Rong Dai ◽

Ming-Hui Li ◽

Xin-Yuan Chen ◽

Ke Zhang ◽

...

Keyword(s):

Electron Density ◽

Cone Beam Ct ◽

Density Measurement ◽

Dual Energy ◽

Cone Beam ◽

Imaging Method ◽

Basis Material ◽

X Ray ◽

Dual Energy Imaging ◽

Set Up

Purpose. To develop a dual energy imaging method to improve the accuracy of electron density measurement with a cone-beam CT (CBCT) device.Materials and Methods. The imaging system is the XVI CBCT system on Elekta Synergy linac. Projection data were acquired with the high and low energy X-ray, respectively, to set up a basis material decomposition model. Virtual phantom simulation and phantoms experiments were carried out for quantitative evaluation of the method. Phantoms were also scanned twice with the high and low energy X-ray, respectively. The data were decomposed into projections of the two basis material coefficients according to the model set up earlier. The two sets of decomposed projections were used to reconstruct CBCT images of the basis material coefficients. Then, the images of electron densities were calculated with these CBCT images.Results. The difference between the calculated and theoretical values was within 2% and the correlation coefficient of them was about 1.0. The dual energy imaging method obtained more accurate electron density values and reduced the beam hardening artifacts obviously.Conclusion. A novel dual energy CBCT imaging method to calculate the electron densities was developed. It can acquire more accurate values and provide a platform potentially for dose calculation.

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Dental cone-beam CT reconstruction from limited-angle view data based on compressed-sensing (CS) theory for fast, low-dose X-ray imaging

Journal of the Korean Physical Society ◽

10.3938/jkps.64.1907 ◽

2014 ◽

Vol 64 (12) ◽

pp. 1907-1911

Author(s):

Uikyu Je ◽

Hyosung Cho ◽

Minsik Lee ◽

Jieun Oh ◽

Yeonok Park ◽

...

Keyword(s):

Compressed Sensing ◽

Low Dose ◽

Cone Beam Ct ◽

Cone Beam ◽

Ct Reconstruction ◽

X Ray ◽

X Ray Imaging ◽

Limited Angle

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X-ray scatter correction algorithm for cone beam CT imaging

Medical Physics ◽

10.1118/1.1711475 ◽

2004 ◽

Vol 31 (5) ◽

pp. 1195-1202 ◽

Cited By ~ 220

Author(s):

Ruola Ning ◽

Xiangyang Tang ◽

David Conover

Keyword(s):

Cone Beam Ct ◽

Scatter Correction ◽

Ct Imaging ◽

Cone Beam ◽

Correction Algorithm ◽

X Ray

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E-032 High resolution cone beam ct for the assessment of stent apposition after flow diverterstent treatment

10.1136/neurintsurg-2017-snis.104 ◽

2017 ◽

Author(s):

Yuki ◽

T Ishibashi ◽

C Dahmani ◽

Y Abe ◽

S Hataoka ◽

...

Keyword(s):

High Resolution ◽

Cone Beam Ct ◽

Cone Beam

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Interobsever Variability of Measurements for Flatfoot Deformity Using High Resolution Weightbearing Cone-Beam CT Examination According to Reader Experience

Foot & Ankle Orthopaedics ◽

10.1177/2473011416s00209 ◽

2016 ◽

Vol 1 (1) ◽

pp. 2473011416S0020

Author(s):

Cesar Cesar Netto ◽

Shadpour Demehri ◽

Eric J. Dein ◽

Hanci Zhang ◽

Gaurav K. Thawait ◽

...

Keyword(s):

High Resolution ◽

Cone Beam Ct ◽

Cone Beam ◽

Ct Examination ◽

Reader Experience

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High-resolution video-based EPID for cone beam CT

10.1117/12.480484 ◽

2003 ◽

Author(s):

Farhad A. Ghelmansarai ◽

Ali R. Bani-Hashemi ◽

Juan C. Celi ◽

Paco Hernandez ◽

Ed Calderon ◽

...

Keyword(s):

High Resolution ◽

Cone Beam Ct ◽

Cone Beam

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Imaging artifacts of Onyx and PHIL on conventional CT, cone-beam CT and MRI in an animal model

Interventional Neuroradiology ◽

10.1177/1591019918782692 ◽

2018 ◽

Vol 24 (6) ◽

pp. 693-701 ◽

Cited By ~ 11

Author(s):

Dominik F Vollherbst ◽

Ruth Otto ◽

Thuy Do ◽

Hans U Kauczor ◽

Martin Bendszus ◽

...

Keyword(s):

Cone Beam Ct ◽

Cone Beam ◽

Embolic Agent ◽

In Vivo Model ◽

Ethylene Vinyl Alcohol ◽

Embolic Agents ◽

Liquid Embolic ◽

Conventional Ct ◽

Ct And Mri

Background and purpose A frequently reported drawback of ethylene vinyl alcohol copolymer-based liquid embolic agents is the production of artifacts in diagnostic imaging. New embolic agents, such as Precipitating hydrophobic injectable liquid (PHIL; MicroVention, Tustin, CA, USA), are supposed to induce significantly fewer artifacts. The purpose of this study is to assess the degree of artifacts induced by the liquid embolic agents Onyx (Medtronic Neurovascular, Irvine, CA, USA) and PHIL in conventional computed tomography (CT), cone-beam CT and magnetic resonance imaging (MRI) in an experimental in vivo model. Materials and methods In 10 pigs the rete mirabile was embolized with Onyx ( n = 5) or PHIL ( n = 5). After embolization, conventional CT, cone-beam CT and MRI were performed. The degree of artifacts was graded qualitatively (five-point scale; for CT and MRI) and quantitatively (HUs of well-defined regions of interest (ROIs); for CT only). Results Artifacts were significantly more severe for Onyx both in the qualitative (e.g. conventional CT: 2 versus 5 (medians); p = 0.008) and in the quantitative image analysis (e.g. cone-beam CT: standard deviation of a ROI near to the embolic agent cast, 94 HU versus 38 HU (medians); p = 0.008). Neither Onyx nor PHIL produced any apparent artifacts in MRI. Conclusion PHIL produces fewer artifacts than Onyx in conventional CT and cone-beam CT in an experimental in vivo model.

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