The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Dirk Vandermeulen - One of the best experts on this subject based on the ideXlab platform.
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An investigation of matching symmetry in the human pinnae with possible implications for 3D ear recognition and sound localization.
Journal of anatomy, 2014Co-Authors: Peter Claes, Jonas Reijniers, Mark D. Shriver, Jonathan Snyders, Paul Suetens, Joachim Nielandt, Guy De Tré, Dirk VandermeulenAbstract:The human external ears, or pinnae, have an intriguing shape and, like most parts of the human external body, bilateral symmetry is observed between left and right. It is a well-known part of our auditory sensory system and mediates the spatial localization of incoming sounds in 3D from monaural cues due to its shape-specific filtering as well as binaural cues due to the paired bilateral locations of the left and right ears. Another less broadly appreciated aspect of the human pinna shape is its uniqueness from one individual to another, which is on the level of what is seen in fingerprints and facial features. This makes pinnae very useful in human identification, which is of great interest in biometrics and forensics. Anatomically, the type of symmetry observed is known as matching symmetry, with structures present as separate mirror copies on both sides of the body, and in this work we report the first such investigation of the human pinna in 3D. Within the framework of geometric morphometrics, we started by partitioning ear shape, represented in a spatially dense way, into patterns of symmetry and asymmetry, following a two-factor anova design. Matching symmetry was measured in all substructures of the pinna anatomy. However, substructures that ‘stick out’ such as the helix, tragus, and lobule also contained a fair degree of asymmetry. In contrast, substructures such as the conchae, antitragus, and Antihelix expressed relatively stronger degrees of symmetric variation in relation to their levels of asymmetry. Insights gained from this study were injected into an accompanying identification setup exploiting matching symmetry where improved performance is demonstrated. Finally, possible implications of the results in the context of ear recognition as well as sound localization are discussed.
Ronald R Grimwood - One of the best experts on this subject based on the ideXlab platform.
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topical nitroglycerin a promising treatment option for chondrodermatitis nodularis helicis
Journal of The American Academy of Dermatology, 2011Co-Authors: Valerie Flynn, Cary Chisholm, Ronald R GrimwoodAbstract:Background Chondrodermatitis nodularis helicis (CNH) is a painful nodule that often interferes with sleep and occurs on the helix or Antihelix of the ear in older patients. Although several case reports describe a variety of seemingly effective surgical and conservative treatment options, well-studied treatment modalities have varying efficacy rates and can often demonstrate disappointing results. Objectives The purpose of this study was to evaluate the efficacy of 2% topical nitroglycerin for the treatment of CNH. Methods A retrospective chart review was performed in 12 patients given the diagnosis of CNH who received 2% topical nitroglycerin twice daily for therapy. Therapeutic efficacy was determined by identifying improvement in the appearance and symptomatology of the lesion. Results A total of 13 lesions in 12 patients were treated, with 12 (92%) lesions demonstrating improvement with the use of topical nitroglycerin. Eight of 13 (61.5%) CNH lesions developed complete clearance and resolution of symptoms, requiring no further treatment. Four of 13 (30.8%) lesions were found to have only symptomatic improvement, and these patients continued to use the ointment as needed. One of 12 (8.3%) patients found no benefit with the treatment but had also failed multiple other treatments modalities. Limitations Limitations include the small number of patients treated and the retrospective nature of the study. Conclusions Topical nitroglycerin demonstrated efficacy in treating both the symptoms and lesional appearance of CNH in a noninvasive manner, with an overall success rate that is comparable with other published methods.
Mohammed Almajed - One of the best experts on this subject based on the ideXlab platform.
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Great auricular nerve blockade using high resolution ultrasound: a volunteer study
Anaesthesia, 2010Co-Authors: Ahmed Thallaj, P. Marhofer, Bernhard Moriggl, B. M. Delvi, Stephan C. Kettner, Mohammed AlmajedAbstract:This prospective, observational volunteer study aimed to describe the appearance of the great auricular nerve using ultrasound and its blockade under ultrasound guidance. An in-plane needle guidance technique was used for blockade of the great auricular nerve with 0.1 ml mepivacaine 1%. Sensory block was evaluated by pinprick testing in comparison with the contralateral area propriae. The great auricular nerve was successfully seen in all volunteers and the tail of the helix, antitragus, lobula and mandibular angle were blocked in all cases whereas the Antihelix and concha were never blocked. Ultrasound imaging of the great auricular nerve can be reliably achieved and successful blockade with minimal volumes of local anaesthetic is another example of the benefits of ultrasound-guided peripheral nerve blocks.
Peter Claes - One of the best experts on this subject based on the ideXlab platform.
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An investigation of matching symmetry in the human pinnae with possible implications for 3D ear recognition and sound localization.
Journal of anatomy, 2014Co-Authors: Peter Claes, Jonas Reijniers, Mark D. Shriver, Jonathan Snyders, Paul Suetens, Joachim Nielandt, Guy De Tré, Dirk VandermeulenAbstract:The human external ears, or pinnae, have an intriguing shape and, like most parts of the human external body, bilateral symmetry is observed between left and right. It is a well-known part of our auditory sensory system and mediates the spatial localization of incoming sounds in 3D from monaural cues due to its shape-specific filtering as well as binaural cues due to the paired bilateral locations of the left and right ears. Another less broadly appreciated aspect of the human pinna shape is its uniqueness from one individual to another, which is on the level of what is seen in fingerprints and facial features. This makes pinnae very useful in human identification, which is of great interest in biometrics and forensics. Anatomically, the type of symmetry observed is known as matching symmetry, with structures present as separate mirror copies on both sides of the body, and in this work we report the first such investigation of the human pinna in 3D. Within the framework of geometric morphometrics, we started by partitioning ear shape, represented in a spatially dense way, into patterns of symmetry and asymmetry, following a two-factor anova design. Matching symmetry was measured in all substructures of the pinna anatomy. However, substructures that ‘stick out’ such as the helix, tragus, and lobule also contained a fair degree of asymmetry. In contrast, substructures such as the conchae, antitragus, and Antihelix expressed relatively stronger degrees of symmetric variation in relation to their levels of asymmetry. Insights gained from this study were injected into an accompanying identification setup exploiting matching symmetry where improved performance is demonstrated. Finally, possible implications of the results in the context of ear recognition as well as sound localization are discussed.
James M Smartt - One of the best experts on this subject based on the ideXlab platform.
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interrater reliability of a phenotypic assessment tool for the ear morphology in microtia
American Journal of Medical Genetics Part A, 2013Co-Authors: Daniela V Luquetti, Babette S Saltzman, Kathleen C Y Sie, Craig B Birgfeld, Brian G Leroux, Kelly N Evans, James M SmarttAbstract:The Elements of Morphology Standard Terminology working group published standardized definitions for external ear morphology. The primary objective of our study was to use these descriptions to evaluate the interrater reliability for specific features associated with microtia. We invited six raters from three different subspecialities to rate 100 ear photographs on 32 features. We calculated overall and within specialty and professional experience intraclass correlation coefficients (ICC) and 95% confidence intervals. A total of 600 possible observations were recorded for each feature. The overall interrater reliability ranged from 0.04 (95%CI: 0.00–0.14) for the width of the Antihelix inferior crus to 0.93 (95%CI: 0.91–0.95) for the presence of the inferior crux of the Antihelix. The reliability for quantitative characteristics such as length or width of an ear structure was generally lower than the reliability for qualitative characteristics (e.g. presence or absence of an ear structure). Categories with very poor interrater reliability included anti-helix inferior crux width (0.04, 95%CI: 0.00–0.14), crux helix extension (0.17, 95% CI 0.00–0.37), and shape of the incisura (0.14, 95%CI: 0.01–0.27). There were no significant differences in reliability estimates by specialty or professional experience for most variables. Our study showed that it is feasible to systematically characterize many of structures of the ear that are affected in microtia. We incorporated these descriptions into a standardized phenotypic assessment tool (PAT-Microtia) that might be used in multicenter research studies to identify sub-phenotypes for future studies of microtia.