Debilitating hearing loss (HL) affects ~6% of the human population. Only 20% of the people in nee... more Debilitating hearing loss (HL) affects ~6% of the human population. Only 20% of the people in need of a hearing assistive device will eventually seek and acquire one. The number of people that are satisfied with their Hearing Aids (HAids) and continue using them in the long term is even lower. Understanding the personal, behavioral, environmental, or other factors that correlate with the optimal HAid fitting and with users' experience of HAids is a significant step in improving patient satisfaction and quality of life, while reducing societal and financial burden. In SMART BEAR we are addressing this need by making use of the capacity of modern HAids to provide dynamic logging of their operation and by combining this information with a big amount of information about the medical, environmental, and social context of each HAid user. We are studying hearing rehabilitation through a 12-month continuous monitoring of HL patients, collecting data, such as participants' demographi...
Benign paroxysmal positional vertigo (BPPV) is the most common type of vertigo. The symptoms of B... more Benign paroxysmal positional vertigo (BPPV) is the most common type of vertigo. The symptoms of BPPV typically appear after angular movements of the head. BPPV leads to dizziness, nausea and imbalance. In this study, we examined a model of the semi-circular canal (SCC) with fully 3D three dimensional anatomical data from specific patient. A full Navier-Stokes equations and continuity equations are used for fluid domain with Arbitrary-Lagrangian Eulerian (ALE) formulation for mesh motion of finite element. Fluid-structure interaction for fluid coupling with cupula deformation is used. Particle tracking algorithm is implemented for particle motion. Motion of the otoconia particles which is main cause for BPPV is simulated. Velocity distribution, shear stress and force from endolymph side are presented for patient specific three SCC. We compared our numerical models with experiments with head moving and nystagmus eye tracking. Numerical simulation can give more details and understandin...
Background Dizziness and imbalance are common symptoms that are often inadequately diagnosed or m... more Background Dizziness and imbalance are common symptoms that are often inadequately diagnosed or managed, due to a lack of dedicated specialists. Decision Support Systems (DSS) may support first-line physicians to diagnose and manage these patients based on personalised data. Aim To examine the diagnostic accuracy and application of the EMBalance DSS for diagnosis and management of common vestibular disorders in primary care. Methods Patients with persistent dizziness were recruited from primary care in Germany, Greece, Belgium and the UK and randomised to primary care clinicians assessing the patients with (+ DSS) versus assessment without (− DSS) the EMBalance DSS. Subsequently, specialists in neuro-otology/audiovestibular medicine performed clinical evaluation of each patient in a blinded way to provide the “gold standard” against which the + DSS, − DSS and the DSS as a standalone tool (i.e. without the final decision made by the clinician) were validated. Results One hundred nine...
EAI Endorsed Transactions on Pervasive Health and Technology, 2018
Hearing impairment is a problem faced by many people, mostly the elderly population but occurs ev... more Hearing impairment is a problem faced by many people, mostly the elderly population but occurs even in newborns. Experimental tests performed on patients give information of the level of hearing impairment and the place where the problem is located. In order to understand process of hearing and hearing impairments it would be very useful to have a look inside, but it is not possible with any experimental equipment. However, it is possible to make a virtual look inside human auditory system by development of numerical model. Using data obtained by experimental research it is possible to make sufficiently detailed model and use it to gain new knowledge that can help in understanding of hearing process and problems with hearing. In this paper one such model will be presented. The model contains mechanical and fluid elements of the middle and inner ear.
Accurate reconstruction of the inner ear is a prerequisite for the modelling and understanding of... more Accurate reconstruction of the inner ear is a prerequisite for the modelling and understanding of the inner ear mechanics. In this study, we present a semi-automated methodology for accurate reconstruction of the major inner ear structures (scalae, basilar membrane, stapes and semicircular canals). For this purpose, high resolution microCT images of a human specimen were used. The segmentation methodology is based on an iterative level set algorithm which provides the borders of the structures of interest. An enhanced coupled level set method which allows the simultaneous multiple image labeling without any overlapping regions has been developed for this purpose. The marching cube algorithm was applied in order to extract the surface from the segmented volume. The reconstructed geometries are then post-processed to improve the basilar membrane geometry to realistically represent physiologic dimensions. The final reconstructed model is compared to the available data from the literature. The results show that our generated inner ear structures are in good agreement with the published ones, while our approach is the most realistic in terms of the basilar membrane thickness and width reconstruction.
2016 38th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2016
We present finite element (FE) modeling approaches of ear mechanics including 3-dimensional (3D) ... more We present finite element (FE) modeling approaches of ear mechanics including 3-dimensional (3D) reconstruction of the human middle and inner ear. Specifically, we demonstrate a semi-automatic methodology for the 3D reconstruction of the inner ear structures, a FE harmonic response model of the middle ear to predict the stapes footplate frequency response, a 2D FE slice model of the cochlea for the coupled response at the micromechanical level for either acoustic or electrical excitation and a coupled FE middle ear model with a simplified cochlea box model to simulate the basilar membrane velocity in response to acoustic excitation. The proposed methodologies are validated against experimental and literature data and the results are in good agreement.
2016 IEEE International Conference on Imaging Systems and Techniques (IST), 2016
The human cochlea is responsible for transducing mechanical stimuli to electrical signals. Howeve... more The human cochlea is responsible for transducing mechanical stimuli to electrical signals. However, there are aspects of cochlear physiology that are not clearly understood and computational modeling has been recently used for this purpose. The computational approaches are usually based on artificial cochlea geometries, which present the cochlea as a box model. In this work, we present a system for the annotation of realistic histological images of the inner ear to reconstruct the cochlea structures using a realistic centerline. Using this approach the user can reconstruct as many structures are visible at the histological images or simplified geometries. The system gives the capabilities to modify the shape, size and length of the basilar membrane and scalae structures. Also, a visualization platform is provided. The approach can directly be used for modeling of inner ear mechanics implementing parametric design to understand accurately the mechanism of basilar membrane excitation from the mechanical stimuli of the pressure at the level of the stapes footplate.
13th IEEE International Conference on BioInformatics and BioEngineering, 2013
The SIFEM project targets the development of an infrastructure in order to semantically link open... more The SIFEM project targets the development of an infrastructure in order to semantically link open source tools and libraries with existing data as well as new knowledge towards the multi-scale finite element modelling of the innerear. The SIFEM system is designed based on an open architecture schema that consists of a set of tools and subsystems in order to develop robust multi-scale models. The project mainly delivers: (i) tools for finite elements modelling, (ii) cochlea reconstruction tool and (iii) 3D inner ear models visualization tool. The main scientific results contribute to the knowledge of alterations associated to diverse cochlear disorders and could lead, in long-term, to personalized healthcare. The overview of the SIFEM platform and its architecture is presented in this paper.
Background: The variations in the anatomy of the external branch of the superior laryngeal nerve ... more Background: The variations in the anatomy of the external branch of the superior laryngeal nerve (EBSLN) are generally classified according to the relationship of the nerve to the superior thyroid artery, or the superior pole of the thyroid. Both artery and superior pole are themselves variable landmarks, and therefore are not consistent between subjects. We sought to examine EBSLN anatomy in relation to alternate, more consistent surgical landmarks. Methods: Fifteen hemi-larynges from 20 embalmed human cadavers were dissected anatomically. Each nerve was categorized using established classification systems, and terminal branching patterns were also noted. Nerve location was recorded in relation to three different constant anatomical structures: the laryngeal prominence, midline junction of the cricothyroid muscles and ipsilateral cricothyroid joint. Results: All cadavers were of European descent. The EBSLN had two branches to the cricothyroid muscle in 34% of cases. The EBSLN anatomical types found were mainly Cernea type 1 (80%), with 7% type 2a and 13% type Ni. An EBSLN was more likely to lie in an 'at risk' location if the subject was less than 160 cm tall. The EBSLN entered the crico-thyroid muscle at a median distance of 14 mm lateral from the laryngeal prominence and 8 mm inferiorly. The median distance from the medial-most point of the cricothyroid muscle junction was 14 mm laterally and 14 mm superiorly, and from the cricothyroid joint the entry lay a median distance of 10 mm superiorly and 11 mm medially. Conclusions: The variability of EBSLN anatomy is again evident, as is the need for careful and knowledgeable surgical technique. New surgical landmarks for the relations of the insertion of the EBSLN reveal a deployment range for each, but one of more of these landmarks may prove useful in thyroid surgery.
Clinical otolaryngology : official journal of ENT-UK ; official journal of Netherlands Society for Oto-Rhino-Laryngology & Cervico-Facial Surgery, 2011
Otology & neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology, 2013
To investigate the therapeutic efficacy of intratympanic dexamethasone combined with systemic pre... more To investigate the therapeutic efficacy of intratympanic dexamethasone combined with systemic prednisolone in patients with idiopathic sudden sensorineural hearing loss (ISSNHL). Prospective, quasirandomized, multicenter clinical trial. One university hospital and 2 affiliated hospitals. A total of 92 eligible patients with ISSNHL were allocated into 2 groups. Patients in the control group were treated with systemic prednisolone alone. Patients of the combined treatment group received additionally 3 intratympanic dexamethasone injections within 5 days. The main outcome measures used were the differences between pretreatment and posttreatment pure-tone audiometry averages (PTAs) and speech discrimination scores (SDSs). Successful treatment was defined as a greater than 10 dB improvement in PTA and 15% in SDS. The final assessment of hearing was performed 3 months after completion of treatment. Significant hearing recovery was observed in 31 (67.39%) of 46 cases, and in 24 (52.17%) of 46 control patients. Patients receiving combination therapy had a median improvement in PTA of 23.12 dB and a median increase in SDS of 32%. In the control group, the median hearing gain was 16.87 dB and 18%, respectively. The differences between the 2 groups were not statistically significant (p = 0.10 and p = 0.13). However, after performing a post hoc analysis by excluding individuals with profound hearing loss (PTA, >90 dB), the combined treatment group showed significant improvement compared with the control group (p = 0.04). No serious complications or adverse reactions were reported. The addition of intratympanic steroids to the conventional systemic steroid therapy may provide a safe and potentially effective therapeutic option in patients with mild-to-severe ISSNHL.
Otology & neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology, 2012
Hearing loss in Paget's disease of bone (PDB) is typically mixed and bila... more Hearing loss in Paget's disease of bone (PDB) is typically mixed and bilateral. Although different mechanisms have been proposed, the pathophysiology of hearing impairment remains unclear. The purpose of this study is to describe the histopathologic findings of temporal bones in patients with PDB and elucidate possible pathologic mechanisms related to hearing impairment. This is an archival human temporal bone study of 8 subjects diagnosed with Paget's disease from the temporal bone collection of the UCL Ear Institute. A fractured stapes footplate was observed in 1 temporal bone and stapes footplate fixation in 2 other specimens. Obliteration of Cotugno's canal by extensive bone remodeling was observed in 78% of temporal bones. An intracochlear vestibular schwannoma was observed in 1 specimen (previously reported in the literature). Other findings include microfissures and microfractures of the otic capsule, bleeding in the scalae, strial atrophy, and cystic lesions in the spiral ligament. This study is the first to report a fractured stapes footplate, as a causative lesion of conductive hearing loss in PDB. Extensive bone remodeling around Cotugno canal also was a frequent finding, not reported before in the literature. We hypothesize that sensorineural hearing loss in patients with PDB of the temporal bone may, in some cases, be attributed to obliteration of Cotugno's canal by remodeling pagetoid bone, thus obstructing the venous drainage of the cochlea, with a subsequent effect on the function of stria vascularis and spiral ligament. This seems to be consistent with experimental studies in animals.
Debilitating hearing loss (HL) affects ~6% of the human population. Only 20% of the people in nee... more Debilitating hearing loss (HL) affects ~6% of the human population. Only 20% of the people in need of a hearing assistive device will eventually seek and acquire one. The number of people that are satisfied with their Hearing Aids (HAids) and continue using them in the long term is even lower. Understanding the personal, behavioral, environmental, or other factors that correlate with the optimal HAid fitting and with users' experience of HAids is a significant step in improving patient satisfaction and quality of life, while reducing societal and financial burden. In SMART BEAR we are addressing this need by making use of the capacity of modern HAids to provide dynamic logging of their operation and by combining this information with a big amount of information about the medical, environmental, and social context of each HAid user. We are studying hearing rehabilitation through a 12-month continuous monitoring of HL patients, collecting data, such as participants' demographi...
Benign paroxysmal positional vertigo (BPPV) is the most common type of vertigo. The symptoms of B... more Benign paroxysmal positional vertigo (BPPV) is the most common type of vertigo. The symptoms of BPPV typically appear after angular movements of the head. BPPV leads to dizziness, nausea and imbalance. In this study, we examined a model of the semi-circular canal (SCC) with fully 3D three dimensional anatomical data from specific patient. A full Navier-Stokes equations and continuity equations are used for fluid domain with Arbitrary-Lagrangian Eulerian (ALE) formulation for mesh motion of finite element. Fluid-structure interaction for fluid coupling with cupula deformation is used. Particle tracking algorithm is implemented for particle motion. Motion of the otoconia particles which is main cause for BPPV is simulated. Velocity distribution, shear stress and force from endolymph side are presented for patient specific three SCC. We compared our numerical models with experiments with head moving and nystagmus eye tracking. Numerical simulation can give more details and understandin...
Background Dizziness and imbalance are common symptoms that are often inadequately diagnosed or m... more Background Dizziness and imbalance are common symptoms that are often inadequately diagnosed or managed, due to a lack of dedicated specialists. Decision Support Systems (DSS) may support first-line physicians to diagnose and manage these patients based on personalised data. Aim To examine the diagnostic accuracy and application of the EMBalance DSS for diagnosis and management of common vestibular disorders in primary care. Methods Patients with persistent dizziness were recruited from primary care in Germany, Greece, Belgium and the UK and randomised to primary care clinicians assessing the patients with (+ DSS) versus assessment without (− DSS) the EMBalance DSS. Subsequently, specialists in neuro-otology/audiovestibular medicine performed clinical evaluation of each patient in a blinded way to provide the “gold standard” against which the + DSS, − DSS and the DSS as a standalone tool (i.e. without the final decision made by the clinician) were validated. Results One hundred nine...
EAI Endorsed Transactions on Pervasive Health and Technology, 2018
Hearing impairment is a problem faced by many people, mostly the elderly population but occurs ev... more Hearing impairment is a problem faced by many people, mostly the elderly population but occurs even in newborns. Experimental tests performed on patients give information of the level of hearing impairment and the place where the problem is located. In order to understand process of hearing and hearing impairments it would be very useful to have a look inside, but it is not possible with any experimental equipment. However, it is possible to make a virtual look inside human auditory system by development of numerical model. Using data obtained by experimental research it is possible to make sufficiently detailed model and use it to gain new knowledge that can help in understanding of hearing process and problems with hearing. In this paper one such model will be presented. The model contains mechanical and fluid elements of the middle and inner ear.
Accurate reconstruction of the inner ear is a prerequisite for the modelling and understanding of... more Accurate reconstruction of the inner ear is a prerequisite for the modelling and understanding of the inner ear mechanics. In this study, we present a semi-automated methodology for accurate reconstruction of the major inner ear structures (scalae, basilar membrane, stapes and semicircular canals). For this purpose, high resolution microCT images of a human specimen were used. The segmentation methodology is based on an iterative level set algorithm which provides the borders of the structures of interest. An enhanced coupled level set method which allows the simultaneous multiple image labeling without any overlapping regions has been developed for this purpose. The marching cube algorithm was applied in order to extract the surface from the segmented volume. The reconstructed geometries are then post-processed to improve the basilar membrane geometry to realistically represent physiologic dimensions. The final reconstructed model is compared to the available data from the literature. The results show that our generated inner ear structures are in good agreement with the published ones, while our approach is the most realistic in terms of the basilar membrane thickness and width reconstruction.
2016 38th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2016
We present finite element (FE) modeling approaches of ear mechanics including 3-dimensional (3D) ... more We present finite element (FE) modeling approaches of ear mechanics including 3-dimensional (3D) reconstruction of the human middle and inner ear. Specifically, we demonstrate a semi-automatic methodology for the 3D reconstruction of the inner ear structures, a FE harmonic response model of the middle ear to predict the stapes footplate frequency response, a 2D FE slice model of the cochlea for the coupled response at the micromechanical level for either acoustic or electrical excitation and a coupled FE middle ear model with a simplified cochlea box model to simulate the basilar membrane velocity in response to acoustic excitation. The proposed methodologies are validated against experimental and literature data and the results are in good agreement.
2016 IEEE International Conference on Imaging Systems and Techniques (IST), 2016
The human cochlea is responsible for transducing mechanical stimuli to electrical signals. Howeve... more The human cochlea is responsible for transducing mechanical stimuli to electrical signals. However, there are aspects of cochlear physiology that are not clearly understood and computational modeling has been recently used for this purpose. The computational approaches are usually based on artificial cochlea geometries, which present the cochlea as a box model. In this work, we present a system for the annotation of realistic histological images of the inner ear to reconstruct the cochlea structures using a realistic centerline. Using this approach the user can reconstruct as many structures are visible at the histological images or simplified geometries. The system gives the capabilities to modify the shape, size and length of the basilar membrane and scalae structures. Also, a visualization platform is provided. The approach can directly be used for modeling of inner ear mechanics implementing parametric design to understand accurately the mechanism of basilar membrane excitation from the mechanical stimuli of the pressure at the level of the stapes footplate.
13th IEEE International Conference on BioInformatics and BioEngineering, 2013
The SIFEM project targets the development of an infrastructure in order to semantically link open... more The SIFEM project targets the development of an infrastructure in order to semantically link open source tools and libraries with existing data as well as new knowledge towards the multi-scale finite element modelling of the innerear. The SIFEM system is designed based on an open architecture schema that consists of a set of tools and subsystems in order to develop robust multi-scale models. The project mainly delivers: (i) tools for finite elements modelling, (ii) cochlea reconstruction tool and (iii) 3D inner ear models visualization tool. The main scientific results contribute to the knowledge of alterations associated to diverse cochlear disorders and could lead, in long-term, to personalized healthcare. The overview of the SIFEM platform and its architecture is presented in this paper.
Background: The variations in the anatomy of the external branch of the superior laryngeal nerve ... more Background: The variations in the anatomy of the external branch of the superior laryngeal nerve (EBSLN) are generally classified according to the relationship of the nerve to the superior thyroid artery, or the superior pole of the thyroid. Both artery and superior pole are themselves variable landmarks, and therefore are not consistent between subjects. We sought to examine EBSLN anatomy in relation to alternate, more consistent surgical landmarks. Methods: Fifteen hemi-larynges from 20 embalmed human cadavers were dissected anatomically. Each nerve was categorized using established classification systems, and terminal branching patterns were also noted. Nerve location was recorded in relation to three different constant anatomical structures: the laryngeal prominence, midline junction of the cricothyroid muscles and ipsilateral cricothyroid joint. Results: All cadavers were of European descent. The EBSLN had two branches to the cricothyroid muscle in 34% of cases. The EBSLN anatomical types found were mainly Cernea type 1 (80%), with 7% type 2a and 13% type Ni. An EBSLN was more likely to lie in an 'at risk' location if the subject was less than 160 cm tall. The EBSLN entered the crico-thyroid muscle at a median distance of 14 mm lateral from the laryngeal prominence and 8 mm inferiorly. The median distance from the medial-most point of the cricothyroid muscle junction was 14 mm laterally and 14 mm superiorly, and from the cricothyroid joint the entry lay a median distance of 10 mm superiorly and 11 mm medially. Conclusions: The variability of EBSLN anatomy is again evident, as is the need for careful and knowledgeable surgical technique. New surgical landmarks for the relations of the insertion of the EBSLN reveal a deployment range for each, but one of more of these landmarks may prove useful in thyroid surgery.
Clinical otolaryngology : official journal of ENT-UK ; official journal of Netherlands Society for Oto-Rhino-Laryngology & Cervico-Facial Surgery, 2011
Otology & neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology, 2013
To investigate the therapeutic efficacy of intratympanic dexamethasone combined with systemic pre... more To investigate the therapeutic efficacy of intratympanic dexamethasone combined with systemic prednisolone in patients with idiopathic sudden sensorineural hearing loss (ISSNHL). Prospective, quasirandomized, multicenter clinical trial. One university hospital and 2 affiliated hospitals. A total of 92 eligible patients with ISSNHL were allocated into 2 groups. Patients in the control group were treated with systemic prednisolone alone. Patients of the combined treatment group received additionally 3 intratympanic dexamethasone injections within 5 days. The main outcome measures used were the differences between pretreatment and posttreatment pure-tone audiometry averages (PTAs) and speech discrimination scores (SDSs). Successful treatment was defined as a greater than 10 dB improvement in PTA and 15% in SDS. The final assessment of hearing was performed 3 months after completion of treatment. Significant hearing recovery was observed in 31 (67.39%) of 46 cases, and in 24 (52.17%) of 46 control patients. Patients receiving combination therapy had a median improvement in PTA of 23.12 dB and a median increase in SDS of 32%. In the control group, the median hearing gain was 16.87 dB and 18%, respectively. The differences between the 2 groups were not statistically significant (p = 0.10 and p = 0.13). However, after performing a post hoc analysis by excluding individuals with profound hearing loss (PTA, >90 dB), the combined treatment group showed significant improvement compared with the control group (p = 0.04). No serious complications or adverse reactions were reported. The addition of intratympanic steroids to the conventional systemic steroid therapy may provide a safe and potentially effective therapeutic option in patients with mild-to-severe ISSNHL.
Otology & neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology, 2012
Hearing loss in Paget's disease of bone (PDB) is typically mixed and bila... more Hearing loss in Paget's disease of bone (PDB) is typically mixed and bilateral. Although different mechanisms have been proposed, the pathophysiology of hearing impairment remains unclear. The purpose of this study is to describe the histopathologic findings of temporal bones in patients with PDB and elucidate possible pathologic mechanisms related to hearing impairment. This is an archival human temporal bone study of 8 subjects diagnosed with Paget's disease from the temporal bone collection of the UCL Ear Institute. A fractured stapes footplate was observed in 1 temporal bone and stapes footplate fixation in 2 other specimens. Obliteration of Cotugno's canal by extensive bone remodeling was observed in 78% of temporal bones. An intracochlear vestibular schwannoma was observed in 1 specimen (previously reported in the literature). Other findings include microfissures and microfractures of the otic capsule, bleeding in the scalae, strial atrophy, and cystic lesions in the spiral ligament. This study is the first to report a fractured stapes footplate, as a causative lesion of conductive hearing loss in PDB. Extensive bone remodeling around Cotugno canal also was a frequent finding, not reported before in the literature. We hypothesize that sensorineural hearing loss in patients with PDB of the temporal bone may, in some cases, be attributed to obliteration of Cotugno's canal by remodeling pagetoid bone, thus obstructing the venous drainage of the cochlea, with a subsequent effect on the function of stria vascularis and spiral ligament. This seems to be consistent with experimental studies in animals.
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