Objective measurements of image quality in synchrotron radiation phase-contrast imaging versus digital mammography

The first clinical study of phase-contrast mammography (PCM) with synchrotron radiation was carried out at the Synchrotron Radiation for Medical Physics beamline of the Elettra synchrotron radiation facility in Trieste (Italy) in 2006–2009. The study involved 71 patients with unresolved breast abnormalities after conventional digital mammography and ultrasonography exams carried out at the Radiology Department of Trieste University Hospital. These cases were referred for mammography at the synchrotron radiation facility, with images acquired using a propagation-based phase-contrast imaging technique. To investigate the contribution of phase-contrast effects to the image quality, two experienced radiologists specialized in mammography assessed the visibility of breast abnormalities and of breast glandular structures. The images acquired at the hospital and at the synchrotron radiation facility were compared and graded according to a relative seven-grade visual scoring system. The statistical analysis highlighted that PCM with synchrotron radiation depicts normal structures and abnormal findings with higher image quality with respect to conventional digital mammography.

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High‐resolution imaging of the human incudostapedial joint using synchrotron‐radiation phase‐contrast imaging

Journal of Microscopy ◽

10.1111/jmi.12864 ◽

2020 ◽

Vol 277 (2) ◽

pp. 61-70

Author(s):

S.A. ROHANI ◽

D. ALLEN ◽

B. GARE ◽

N. ZHU ◽

S. AGRAWAL ◽

...

Keyword(s):

High Resolution ◽

Synchrotron Radiation ◽

Phase Contrast ◽

Phase Contrast Imaging ◽

High Resolution Imaging ◽

Contrast Imaging ◽

Resolution Imaging ◽

Incudostapedial Joint ◽

Radiation Phase

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Evaluation of Cochlear Duct Length Measurements From a 3D Analytical Cochlear Model Using Synchrotron Radiation Phase-Contrast Imaging

Otology & Neurotology ◽

10.1097/mao.0000000000002420 ◽

2020 ◽

Vol 41 (1) ◽

pp. e21-e27

Author(s):

Luke W. Helpard ◽

Seyed A. Rohani ◽

Hanif M. Ladak ◽

Sumit K. Agrawal

Keyword(s):

Synchrotron Radiation ◽

Phase Contrast ◽

Phase Contrast Imaging ◽

Contrast Imaging ◽

Cochlear Duct ◽

Cochlear Model ◽

Length Measurements ◽

Cochlear Duct Length ◽

Radiation Phase

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Microvoids in Solids: Synchrotron Radiation Phase Contrast Imaging and Simulations

physica status solidi (b) ◽

10.1002/pssb.201800209 ◽

2018 ◽

Vol 255 (9) ◽

pp. 1800209 ◽

Cited By ~ 2

Author(s):

Victor G. Kohn ◽

Tatiana S. Argunova ◽

Jung Ho Je

Keyword(s):

Synchrotron Radiation ◽

Phase Contrast ◽

Phase Contrast Imaging ◽

Contrast Imaging ◽

Radiation Phase

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Three-dimensional tonotopic mapping of the human cochlea based on synchrotron radiation phase-contrast imaging

Scientific Reports ◽

10.1038/s41598-021-83225-w ◽

2021 ◽

Vol 11 (1) ◽

Cited By ~ 1

Author(s):

Hao Li ◽

Luke Helpard ◽

Jonas Ekeroot ◽

Seyed Alireza Rohani ◽

Ning Zhu ◽

...

Keyword(s):

Synchrotron Radiation ◽

Phase Contrast ◽

Spiral Ganglion ◽

Three Dimensional ◽

Nerve Fibers ◽

Frequency Function ◽

Phase Contrast Imaging ◽

Contrast Imaging ◽

Human Cochlea ◽

Radiation Phase

AbstractThe human cochlea transforms sound waves into electrical signals in the acoustic nerve fibers with high acuity. This transformation occurs via vibrating anisotropic membranes (basilar and tectorial membranes) and frequency-specific hair cell receptors. Frequency-positions can be mapped within the cochlea to create a tonotopic chart which fits an almost-exponential function with lowest frequencies positioned apically and highest frequencies positioned at the cochlear base (Bekesy 1960, Greenwood 1961). To date, models of frequency positions have been based on a two-dimensional analysis with inaccurate representations of the cochlear hook region. In the present study, the first three-dimensional frequency analysis of the cochlea using dendritic mapping to obtain accurate tonotopic maps of the human basilar membrane/organ of Corti and the spiral ganglion was performed. A novel imaging technique, synchrotron radiation phase-contrast imaging, was used and a spiral ganglion frequency function was estimated by nonlinear least squares fitting a Greenwood-like function (F = A (10ax − K)) to the data. The three-dimensional tonotopic data presented herein has large implications for validating electrode position and creating customized frequency maps for cochlear implant recipients.

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Microbubble-based synchrotron radiation phase contrast imaging: basic study and angiography applications

Physics in Medicine and Biology ◽

10.1088/0031-9155/56/12/004 ◽

2011 ◽

Vol 56 (12) ◽

pp. 3503-3512 ◽

Cited By ~ 29

Author(s):

Rongbiao Tang ◽

Yan Xi ◽

Wei-Min Chai ◽

Yongting Wang ◽

Yongjing Guan ◽

...

Keyword(s):

Synchrotron Radiation ◽

Phase Contrast ◽

Phase Contrast Imaging ◽

Contrast Imaging ◽

Basic Study ◽

Radiation Phase

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Characterization of the human helicotrema: implications for cochlear duct length and frequency mapping

Journal of Otolaryngology - Head and Neck Surgery ◽

10.1186/s40463-019-0398-8 ◽

2020 ◽

Vol 49 (1) ◽

Cited By ~ 2

Author(s):

Luke Helpard ◽

Hao Li ◽

Helge Rask-Andersen ◽

Hanif M. Ladak ◽

Sumit K. Agrawal

Keyword(s):

Regression Analysis ◽

Synchrotron Radiation ◽

Phase Contrast ◽

Anatomical Variation ◽

Phase Contrast Imaging ◽

Patient Specific ◽

Contrast Imaging ◽

Cochlear Duct ◽

Cochlear Duct Length ◽

Radiation Phase

Abstract Background Despite significant anatomical variation amongst patients, cochlear implant frequency-mapping has traditionally followed a patient-independent approach. Basilar membrane (BM) length is required for patient-specific frequency-mapping, however cochlear duct length (CDL) measurements generally extend to the apical tip of the entire cochlea or have no clearly defined end-point. By characterizing the length between the end of the BM and the apical tip of the entire cochlea (helicotrema length), current CDL models can be corrected to obtain the appropriate BM length. Synchrotron radiation phase-contrast imaging has made this analysis possible due to the soft-tissue contrast through the entire cochlear apex. Methods Helicotrema linear length and helicotrema angular length measurements were performed on synchrotron radiation phase-contrast imaging data of 14 cadaveric human cochleae. On a sub-set of six samples, the CDL to the apical tip of the entire cochlea (CDLTIP) and the BM length (CDLBM) were determined. Regression analysis was performed to assess the relationship between CDLTIP and CDLBM. Results The mean helicotrema linear length and helicotrema angular length values were 1.6 ± 0.9 mm and 67.8 ± 37.9 degrees, respectively. Regression analysis revealed the following relationship between CDLTIP and CDLBM: CDLBM = 0.88(CDLTIP) + 3.71 (R2 = 0.995). Conclusion This is the first known study to characterize the length of the helicotrema in the context of CDL measurements. It was determined that the distance between the end of the BM and the tip of the entire cochlea is clinically consequential. A relationship was determined that can predict the BM length of an individual patient based on their respective CDL measured to the apical tip of the cochlea.

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