The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform
Hannes Maier - One of the best experts on this subject based on the ideXlab platform.
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Outer Ear canal sound pressure and bone vibration measurement in ssd and chl patients using a transcutaneous bone conduction instrument
Hearing Research, 2016Co-Authors: Mohammad Ghoncheh, Giorgio Lilli, Thomas Lenarz, Hannes MaierAbstract:The intraoperative and postoperative objective functional assessment of transcutaneous bone conduction implants is still a challenge. Here we compared intraoperative Laser-Doppler-vibrometry (LDV, Polytec Inc.) to measure vibration of the bone close to the implant to Outer Ear Canal Sound Pressure Level (OEC-SPL) measurements. Twelve single sided deafness (SSD) patients with contralateral intact ossicular chains and eight bilateral conductive hEaring loss (CHL) patients were included in the study. SSD patients had a minor average air-bone-gap (ABG) of 0.4 ± 0.4 dB (0.5, 1, 2, 4 kHz mean value (MV) ± standard deviation (SD)) on the contralateral side where a normal transmission between cochlea and the tympanic membrane can be assumed. CHL patients had an impaired middle Ear transmission with a mean ABG of 46.0 ± 7.9 dB (MV±SD). Vibration and OEC-SPL responses could reliably be recorded with a minimal signal-to-noise ratio of at least 12 dB. Average OEC-SPL on the contralateral side and intraoperative vibration measurements were strongly correlated in SSD (r2 = 0.75) and CHL (r2 = 0.86) patients. The correlation in individual results between OEC-SPL and vibration measurements was weak, indicating some underlying inter-individual variability. The high correlation of average responses showed that OEC-SPL are closely linked to bone vibration, although both cannot be equivalently used for intraoperative testing due to the high variability in individual results. On the other hand, OEC-SPL provides an easy and affordable measurement tool to monitor stability and functionality postoperatively using individual reference measurements. We observed no significant differences (t-test, p < 0.05) by comparing results from contralateral OEC-SPL in twelve SSD and eight CHL patients at frequencies between 0.5 and 8 kHz. This implies that the part of the measured sound pressure in the Ear canal originating from the cochlea and emitted by the tympanic is not dominant and OEC-SPL is mainly due to vibration of the external Ear-canal walls as the only other pathway of BC sound to reach the Ear canal. In addition, the transcranial attenuation (contralateral Outer Ear canal sound pressure divided by ipsilateral) was compared to previous studies measuring vibration by LDV and accelerometer. The trend in the average transcranial attenuation in patients was similar to previous studies measuring the OEC-SPL with less than 5 dB difference.
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Outer Ear canal sound pressure and bone vibration measurement in SSD and CHL patients using a transcutaneous bone conduction instrument
Hearing Research, 2015Co-Authors: Mohammad Ghoncheh, Giorgio Lilli, Thomas Lenarz, Hannes MaierAbstract:The intraoperative and postoperative objective functional assessment of transcutaneous bone conduction implants is still a challenge. Here we compared intraoperative Laser-Doppler-vibrometry (LDV, Polytec Inc.) to measure vibration of the bone close to the implant to Outer Ear Canal Sound Pressure Level (OEC-SPL) measurements. Twelve single sided deafness (SSD) patients with contralateral intact ossicular chains and eight bilateral conductive hEaring loss (CHL) patients were included in the study. SSD patients had a minor average air-bone-gap (ABG) of 0.4 ± 0.4 dB (0.5, 1, 2, 4 kHz mean value (MV) ± standard deviation (SD)) on the contralateral side where a normal transmission between cochlea and the tympanic membrane can be assumed. CHL patients had an impaired middle Ear transmission with a mean ABG of 46.0 ± 7.9 dB (MV±SD). Vibration and OEC-SPL responses could reliably be recorded with a minimal signal-to-noise ratio of at least 12 dB. Average OEC-SPL on the contralateral side and intraoperative vibration measurements were strongly correlated in SSD (r2 = 0.75) and CHL (r2 = 0.86) patients. The correlation in individual results between OEC-SPL and vibration measurements was weak, indicating some underlying inter-individual variability. The high correlation of average responses showed that OEC-SPL are closely linked to bone vibration, although both cannot be equivalently used for intraoperative testing due to the high variability in individual results. On the other hand, OEC-SPL provides an easy and affordable measurement tool to monitor stability and functionality postoperatively using individual reference measurements. We observed no significant differences (t-test, p
Tong Fang - One of the best experts on this subject based on the ideXlab platform.
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deformable registration of organic shapes via surface intrinsic integrals application to Outer Ear surfaces
Medical Image Computing and Computer-Assisted Intervention, 2010Co-Authors: Sajjad Baloch, Alexander Zouhar, Tong FangAbstract:We propose a method for the deformable registration of organic surfaces. Meaningful correspondences between a source surface and a target surface are established by means of a rich surface descriptor that incorporates three categories of features: (1) local and regional geometry; (2) surface anatomy; and (3) global shape information. First, surface intrinsic, geodesic distance integrals, are exploited to constrain the global geodesic layout. Consequently, the resulting transformation ensures topological consistency. Local geometric features are then introduced to enforce local conformity of various regions. To this end, the extrema of appropriate curvatures -- the extrema of mean curvature, minima of Gauss and minimum principal curvature, and the maxima of maximum principal curvature -- are considered. Regional features are introduced through curvature integrals over various scales. On top of this, explicit anatomical priors are included, thereby resulting in anatomically more consistent registration. The source surface is deformed to the target by minimizing the energy of matching the source features to the target features under a Gaussian propagation model. We validate the proposed method with application to the Outer Ear surfaces.
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MCV - Deformable registration of organic shapes via surface intrinsic integrals: application to Outer Ear surfaces
Medical Computer Vision. Recognition Techniques and Applications in Medical Imaging, 2010Co-Authors: Sajjad Baloch, Alexander Zouhar, Tong FangAbstract:We propose a method for the deformable registration of organic surfaces. Meaningful correspondences between a source surface and a target surface are established by means of a rich surface descriptor that incorporates three categories of features: (1) local and regional geometry; (2) surface anatomy; and (3) global shape information. First, surface intrinsic, geodesic distance integrals, are exploited to constrain the global geodesic layout. Consequently, the resulting transformation ensures topological consistency. Local geometric features are then introduced to enforce local conformity of various regions. To this end, the extrema of appropriate curvatures -- the extrema of mean curvature, minima of Gauss and minimum principal curvature, and the maxima of maximum principal curvature -- are considered. Regional features are introduced through curvature integrals over various scales. On top of this, explicit anatomical priors are included, thereby resulting in anatomically more consistent registration. The source surface is deformed to the target by minimizing the energy of matching the source features to the target features under a Gaussian propagation model. We validate the proposed method with application to the Outer Ear surfaces.
Mohammad Ghoncheh - One of the best experts on this subject based on the ideXlab platform.
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Outer Ear canal sound pressure and bone vibration measurement in ssd and chl patients using a transcutaneous bone conduction instrument
Hearing Research, 2016Co-Authors: Mohammad Ghoncheh, Giorgio Lilli, Thomas Lenarz, Hannes MaierAbstract:The intraoperative and postoperative objective functional assessment of transcutaneous bone conduction implants is still a challenge. Here we compared intraoperative Laser-Doppler-vibrometry (LDV, Polytec Inc.) to measure vibration of the bone close to the implant to Outer Ear Canal Sound Pressure Level (OEC-SPL) measurements. Twelve single sided deafness (SSD) patients with contralateral intact ossicular chains and eight bilateral conductive hEaring loss (CHL) patients were included in the study. SSD patients had a minor average air-bone-gap (ABG) of 0.4 ± 0.4 dB (0.5, 1, 2, 4 kHz mean value (MV) ± standard deviation (SD)) on the contralateral side where a normal transmission between cochlea and the tympanic membrane can be assumed. CHL patients had an impaired middle Ear transmission with a mean ABG of 46.0 ± 7.9 dB (MV±SD). Vibration and OEC-SPL responses could reliably be recorded with a minimal signal-to-noise ratio of at least 12 dB. Average OEC-SPL on the contralateral side and intraoperative vibration measurements were strongly correlated in SSD (r2 = 0.75) and CHL (r2 = 0.86) patients. The correlation in individual results between OEC-SPL and vibration measurements was weak, indicating some underlying inter-individual variability. The high correlation of average responses showed that OEC-SPL are closely linked to bone vibration, although both cannot be equivalently used for intraoperative testing due to the high variability in individual results. On the other hand, OEC-SPL provides an easy and affordable measurement tool to monitor stability and functionality postoperatively using individual reference measurements. We observed no significant differences (t-test, p < 0.05) by comparing results from contralateral OEC-SPL in twelve SSD and eight CHL patients at frequencies between 0.5 and 8 kHz. This implies that the part of the measured sound pressure in the Ear canal originating from the cochlea and emitted by the tympanic is not dominant and OEC-SPL is mainly due to vibration of the external Ear-canal walls as the only other pathway of BC sound to reach the Ear canal. In addition, the transcranial attenuation (contralateral Outer Ear canal sound pressure divided by ipsilateral) was compared to previous studies measuring vibration by LDV and accelerometer. The trend in the average transcranial attenuation in patients was similar to previous studies measuring the OEC-SPL with less than 5 dB difference.
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Outer Ear canal sound pressure and bone vibration measurement in SSD and CHL patients using a transcutaneous bone conduction instrument
Hearing Research, 2015Co-Authors: Mohammad Ghoncheh, Giorgio Lilli, Thomas Lenarz, Hannes MaierAbstract:The intraoperative and postoperative objective functional assessment of transcutaneous bone conduction implants is still a challenge. Here we compared intraoperative Laser-Doppler-vibrometry (LDV, Polytec Inc.) to measure vibration of the bone close to the implant to Outer Ear Canal Sound Pressure Level (OEC-SPL) measurements. Twelve single sided deafness (SSD) patients with contralateral intact ossicular chains and eight bilateral conductive hEaring loss (CHL) patients were included in the study. SSD patients had a minor average air-bone-gap (ABG) of 0.4 ± 0.4 dB (0.5, 1, 2, 4 kHz mean value (MV) ± standard deviation (SD)) on the contralateral side where a normal transmission between cochlea and the tympanic membrane can be assumed. CHL patients had an impaired middle Ear transmission with a mean ABG of 46.0 ± 7.9 dB (MV±SD). Vibration and OEC-SPL responses could reliably be recorded with a minimal signal-to-noise ratio of at least 12 dB. Average OEC-SPL on the contralateral side and intraoperative vibration measurements were strongly correlated in SSD (r2 = 0.75) and CHL (r2 = 0.86) patients. The correlation in individual results between OEC-SPL and vibration measurements was weak, indicating some underlying inter-individual variability. The high correlation of average responses showed that OEC-SPL are closely linked to bone vibration, although both cannot be equivalently used for intraoperative testing due to the high variability in individual results. On the other hand, OEC-SPL provides an easy and affordable measurement tool to monitor stability and functionality postoperatively using individual reference measurements. We observed no significant differences (t-test, p
Sajjad Baloch - One of the best experts on this subject based on the ideXlab platform.
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deformable registration of organic shapes via surface intrinsic integrals application to Outer Ear surfaces
Medical Image Computing and Computer-Assisted Intervention, 2010Co-Authors: Sajjad Baloch, Alexander Zouhar, Tong FangAbstract:We propose a method for the deformable registration of organic surfaces. Meaningful correspondences between a source surface and a target surface are established by means of a rich surface descriptor that incorporates three categories of features: (1) local and regional geometry; (2) surface anatomy; and (3) global shape information. First, surface intrinsic, geodesic distance integrals, are exploited to constrain the global geodesic layout. Consequently, the resulting transformation ensures topological consistency. Local geometric features are then introduced to enforce local conformity of various regions. To this end, the extrema of appropriate curvatures -- the extrema of mean curvature, minima of Gauss and minimum principal curvature, and the maxima of maximum principal curvature -- are considered. Regional features are introduced through curvature integrals over various scales. On top of this, explicit anatomical priors are included, thereby resulting in anatomically more consistent registration. The source surface is deformed to the target by minimizing the energy of matching the source features to the target features under a Gaussian propagation model. We validate the proposed method with application to the Outer Ear surfaces.
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MCV - Deformable registration of organic shapes via surface intrinsic integrals: application to Outer Ear surfaces
Medical Computer Vision. Recognition Techniques and Applications in Medical Imaging, 2010Co-Authors: Sajjad Baloch, Alexander Zouhar, Tong FangAbstract:We propose a method for the deformable registration of organic surfaces. Meaningful correspondences between a source surface and a target surface are established by means of a rich surface descriptor that incorporates three categories of features: (1) local and regional geometry; (2) surface anatomy; and (3) global shape information. First, surface intrinsic, geodesic distance integrals, are exploited to constrain the global geodesic layout. Consequently, the resulting transformation ensures topological consistency. Local geometric features are then introduced to enforce local conformity of various regions. To this end, the extrema of appropriate curvatures -- the extrema of mean curvature, minima of Gauss and minimum principal curvature, and the maxima of maximum principal curvature -- are considered. Regional features are introduced through curvature integrals over various scales. On top of this, explicit anatomical priors are included, thereby resulting in anatomically more consistent registration. The source surface is deformed to the target by minimizing the energy of matching the source features to the target features under a Gaussian propagation model. We validate the proposed method with application to the Outer Ear surfaces.
Thomas Lenarz - One of the best experts on this subject based on the ideXlab platform.
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Outer Ear canal sound pressure and bone vibration measurement in ssd and chl patients using a transcutaneous bone conduction instrument
Hearing Research, 2016Co-Authors: Mohammad Ghoncheh, Giorgio Lilli, Thomas Lenarz, Hannes MaierAbstract:The intraoperative and postoperative objective functional assessment of transcutaneous bone conduction implants is still a challenge. Here we compared intraoperative Laser-Doppler-vibrometry (LDV, Polytec Inc.) to measure vibration of the bone close to the implant to Outer Ear Canal Sound Pressure Level (OEC-SPL) measurements. Twelve single sided deafness (SSD) patients with contralateral intact ossicular chains and eight bilateral conductive hEaring loss (CHL) patients were included in the study. SSD patients had a minor average air-bone-gap (ABG) of 0.4 ± 0.4 dB (0.5, 1, 2, 4 kHz mean value (MV) ± standard deviation (SD)) on the contralateral side where a normal transmission between cochlea and the tympanic membrane can be assumed. CHL patients had an impaired middle Ear transmission with a mean ABG of 46.0 ± 7.9 dB (MV±SD). Vibration and OEC-SPL responses could reliably be recorded with a minimal signal-to-noise ratio of at least 12 dB. Average OEC-SPL on the contralateral side and intraoperative vibration measurements were strongly correlated in SSD (r2 = 0.75) and CHL (r2 = 0.86) patients. The correlation in individual results between OEC-SPL and vibration measurements was weak, indicating some underlying inter-individual variability. The high correlation of average responses showed that OEC-SPL are closely linked to bone vibration, although both cannot be equivalently used for intraoperative testing due to the high variability in individual results. On the other hand, OEC-SPL provides an easy and affordable measurement tool to monitor stability and functionality postoperatively using individual reference measurements. We observed no significant differences (t-test, p < 0.05) by comparing results from contralateral OEC-SPL in twelve SSD and eight CHL patients at frequencies between 0.5 and 8 kHz. This implies that the part of the measured sound pressure in the Ear canal originating from the cochlea and emitted by the tympanic is not dominant and OEC-SPL is mainly due to vibration of the external Ear-canal walls as the only other pathway of BC sound to reach the Ear canal. In addition, the transcranial attenuation (contralateral Outer Ear canal sound pressure divided by ipsilateral) was compared to previous studies measuring vibration by LDV and accelerometer. The trend in the average transcranial attenuation in patients was similar to previous studies measuring the OEC-SPL with less than 5 dB difference.
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Outer Ear canal sound pressure and bone vibration measurement in SSD and CHL patients using a transcutaneous bone conduction instrument
Hearing Research, 2015Co-Authors: Mohammad Ghoncheh, Giorgio Lilli, Thomas Lenarz, Hannes MaierAbstract:The intraoperative and postoperative objective functional assessment of transcutaneous bone conduction implants is still a challenge. Here we compared intraoperative Laser-Doppler-vibrometry (LDV, Polytec Inc.) to measure vibration of the bone close to the implant to Outer Ear Canal Sound Pressure Level (OEC-SPL) measurements. Twelve single sided deafness (SSD) patients with contralateral intact ossicular chains and eight bilateral conductive hEaring loss (CHL) patients were included in the study. SSD patients had a minor average air-bone-gap (ABG) of 0.4 ± 0.4 dB (0.5, 1, 2, 4 kHz mean value (MV) ± standard deviation (SD)) on the contralateral side where a normal transmission between cochlea and the tympanic membrane can be assumed. CHL patients had an impaired middle Ear transmission with a mean ABG of 46.0 ± 7.9 dB (MV±SD). Vibration and OEC-SPL responses could reliably be recorded with a minimal signal-to-noise ratio of at least 12 dB. Average OEC-SPL on the contralateral side and intraoperative vibration measurements were strongly correlated in SSD (r2 = 0.75) and CHL (r2 = 0.86) patients. The correlation in individual results between OEC-SPL and vibration measurements was weak, indicating some underlying inter-individual variability. The high correlation of average responses showed that OEC-SPL are closely linked to bone vibration, although both cannot be equivalently used for intraoperative testing due to the high variability in individual results. On the other hand, OEC-SPL provides an easy and affordable measurement tool to monitor stability and functionality postoperatively using individual reference measurements. We observed no significant differences (t-test, p
