Auditory processing disorder: auditory perception beyond classical audiological testing

Human auditory perception is accomplished with hearing, which is an ability and listening, which is a skill. Pure tone threshold evaluation is the most common test of hearing used in the clinical setting by audiologists. This test focuses on hearing sensitivity in simple sounds (pure tones) and may prove insufficient in identifying listening difficulties in everyday situations. Normal pure tone thresholds do not ensure normal functional hearing (listening), since problems such as reduced speech recognition in noise, or sound localization may be present but remain undetected. Auditory processing is the medical term of listening. This review paper presents the nature of Auditory Processing Disorder, the valid testing approach, its aetiology, clinical populations that may have the disorder and how intervention and management are achieved according to current scientific evidence and clinical practice

Central auditory processing and perception of sound

Η αντίληψη ύπαρξης ήχου σε απουσία εξωτερικής ηχητικής πηγής, αν και δεν είναι πλήρως κατανοητή ως προς την παθοφυσιολογία της, συνδέεται με βλάβες, είτε στο περιφερικό, είτε στο κεντρικό ακουστικό νευρικό σύστημα. Η λειτουργία του κεντρικού ακουστικού νευρικού συστήματος επιτρέπει την επεξεργασία της ακουστικής πληροφορίας, η οποία μεταφέρεται σε πραγματικό χρόνο, τόσο από την περιφέρεια του ακουστικού συστήματος προς το κέντρο της ακοής στον εγκεφαλικό φλοιό, όσο και από τον εγκεφαλικό φλοιό προς τα υποφλοιικά κέντρα της ακοής. Παραδείγματα που έχουν ερευνηθεί είναι οι ακουστικές ψευδαισθήσεις και οι εμβοές. Τα ελλείμματα ακουστικής επεξεργασίας, καθώς και η παθολογία του κεντρικού ακουστικού νευρικού συστήματος μπορούν μερικώς να εξηγήσουν την κλινική εικόνα ασθενών που αντιλαμβάνονται ήχο, όταν αυτός δεν υπάρχει. Με βάση σύγχρονα δημοσιευμένα ερευνητικά δεδομένα η βέλτιστη κλινική προσέγγιση, είτε ψυχιατρικών ασθενών με ακουστικές ψευδαισθήσεις, είτε ασθενών με εμβοές μπορεί να περιλαμβάνει εκτίμηση ακουστικής επεξεργασίας. Η εξέταση ακουστικής επεξεργασίας, μπορεί πρωτίστως να περιλαμβάνει χρονική ανάλυση, ομιλητική ακουομετρία σε θόρυβο και διάκριση συχνοτήτων και με τον τρόπο αυτό να εκτιμά καλύτερα τα καθημερινά προβλήματα του ασθενούς αναφορικά με την ακουστική αντίληψη και την επικοινωνία του.Perception of sound without the presence of an external source, although not fully understood pathophysiologically, is known to be linked to lesions in either the peripheral or the central auditory nervous system. Functionality of the central auditory nervous system permits the processing of auditory information which is mediated in real time both as a bottom-up (from the peripheral auditory nervous system to auditory cortex) and a top-down (from the auditory cortex to subcortical structures) process. Examples of symptoms researched are auditory hallucinations and tinnitus. Auditory processing deficits, as well as, central auditory nervous pathology may partly explain patients perceiving sound in the absence of an external source. Based on current published research, an optimal clinical assessment of either psychiatric patients with auditory hallucinations or patients with tinnitus, may include central auditory processing evaluation. This evaluation may primarily include temporal processing, speech in babble and frequency discrimination abilities of the patient to better assess everyday difficulties in listening and communication

A systematic review and metanalysis of questionnaires used for auditory processing screening and evaluation

The recognition of Auditory Processing Disorder (APD) as a distinct clinical condition that impacts hearing capacity and mental health has gained attention. Although pure tone audiometry is the gold standard for assessing hearing, it inadequately reflects everyday hearing abilities, especially in challenging acoustic environments. Deficits in speech perception in noise, a key aspect of APD, have been linked to an increased risk of dementia. The World Health Organization emphasizes the need for evaluating central auditory function in cases of mild hearing loss and normal audiometry results. Specific questionnaires play a crucial role in documenting and quantifying the difficulties faced by individuals with APD. Validated questionnaires such as the Children's Auditory Processing Performance Scale, the Fisher's Auditory Problems Checklist, and the Auditory Processing Domains Questionnaire are available for children, while questionnaires for adults include items related to auditory functions associated with APD. This systematic review and meta-analysis identified six questionnaires used for screening and evaluating APD with a total of 783 participants across 12 studies. The questionnaires exhibited differences in domains evaluated, scoring methods, and evaluation of listening in quiet and noise. Meta-analysis results demonstrated that individuals with APD consistently exhibited worse scores compared to healthy controls across all questionnaires. Additionally, comparisons with clinical control groups showed varying results. The study highlights (i) the importance of standardized questionnaires in identifying and assessing APD, aiding in its diagnosis and management, and (ii) the need to use sub-scores as well as overall scores of questionnaires to elaborate on specific hearing and listening situations. There is a need to develop more APD specific questionnaires for the adult population as well as for more focused research on APD diagnosed individuals to further establish the validity and reliability of these questionnaires

A European perspective on auditory processing disorder-current knowledge and future research focus

Current notions of \u201chearing impairment,\u201d as reflected in clinical audiological practice, do not acknowledge the needs of individuals who have normal hearing pure tone sensitivity but who experience auditory processing difficulties in everyday life that are indexed by reduced performance in other more sophisticated audiometric tests such as speech audiometry in noise or complex non-speech sound perception. This disorder, defined as \u201cAuditory Processing Disorder\u201d (APD) or \u201cCentral Auditory Processing Disorder\u201d is classified in the current tenth version of the International Classification of diseases as H93.25 and in the forthcoming beta eleventh version. APDs may have detrimental effects on the affected individual, with low esteem, anxiety, and depression, and symptoms may remain into adulthood. These disorders may interfere with learning per se and with communication, social, emotional, and academic-work aspects of life. The objective of the present paper is to define a baseline European APD consensus formulated by experienced clinicians and researchers in this specific field of human auditory science. A secondary aim is to identify issues that future research needs to address in order to further clarify the nature of APD and thus assist in optimumdiagnosis and evidence-based management. This European consensus presents the main symptoms, conditions, and specific medical history elements that should lead to auditory processing evaluation. Consensus on definition of the disorder, optimum diagnostic pathway, and appropriate management are highlighted alongside a perspective on future research focus

A systematic review and metanalysis of questionnaires used for auditory processing screening and evaluation

The recognition of Auditory Processing Disorder (APD) as a distinct clinical condition that impacts hearing capacity and mental health has gained attention. Although pure tone audiometry is the gold standard for assessing hearing, it inadequately reflects everyday hearing abilities, especially in challenging acoustic environments. Deficits in speech perception in noise, a key aspect of APD, have been linked to an increased risk of dementia. The World Health Organization emphasizes the need for evaluating central auditory function in cases of mild hearing loss and normal audiometry results. Specific questionnaires play a crucial role in documenting and quantifying the difficulties faced by individuals with APD. Validated questionnaires such as the Children’s Auditory Processing Performance Scale, the Fisher’s Auditory Problems Checklist, and the Auditory Processing Domains Questionnaire are available for children, while questionnaires for adults include items related to auditory functions associated with APD. This systematic review and meta-analysis identified six questionnaires used for screening and evaluating APD with a total of 783 participants across 12 studies. The questionnaires exhibited differences in domains evaluated, scoring methods, and evaluation of listening in quiet and noise. Meta-analysis results demonstrated that individuals with APD consistently exhibited worse scores compared to healthy controls across all questionnaires. Additionally, comparisons with clinical control groups showed varying results. The study highlights (i) the importance of standardized questionnaires in identifying and assessing APD, aiding in its diagnosis and management, and (ii) the need to use sub-scores as well as overall scores of questionnaires to elaborate on specific hearing and listening situations. There is a need to develop more APD specific questionnaires for the adult population as well as for more focused research on APD diagnosed individuals to further establish the validity and reliability of these questionnaires

A systematic review and metanalysis of questionnaires used for auditory processing screening and evaluation

The recognition of Auditory Processing Disorder (APD) as a distinct clinical condition that impacts hearing capacity and mental health has gained attention. Although pure tone audiometry is the gold standard for assessing hearing, it inadequately reflects everyday hearing abilities, especially in challenging acoustic environments. Deficits in speech perception in noise, a key aspect of APD, have been linked to an increased risk of dementia. The World Health Organization emphasizes the need for evaluating central auditory function in cases of mild hearing loss and normal audiometry results. Specific questionnaires play a crucial role in documenting and quantifying the difficulties faced by individuals with APD. Validated questionnaires such as the Children’s Auditory Processing Performance Scale, the Fisher’s Auditory Problems Checklist, and the Auditory Processing Domains Questionnaire are available for children, while questionnaires for adults include items related to auditory functions associated with APD. This systematic review and meta-analysis identified six questionnaires used for screening and evaluating APD with a total of 783 participants across 12 studies. The questionnaires exhibited differences in domains evaluated, scoring methods, and evaluation of listening in quiet and noise. Meta-analysis results demonstrated that individuals with APD consistently exhibited worse scores compared to healthy controls across all questionnaires. Additionally, comparisons with clinical control groups showed varying results. The study highlights (i) the importance of standardized questionnaires in identifying and assessing APD, aiding in its diagnosis and management, and (ii) the need to use sub-scores as well as overall scores of questionnaires to elaborate on specific hearing and listening situations. There is a need to develop more APD specific questionnaires for the adult population as well as for more focused research on APD diagnosed individuals to further establish the validity and reliability of these questionnaires

Radiation therapy image processing and analysis using image registration and machine learning teachnics for patients with head and neck cancer

In this Doctoral Thesis the purpose was to analyze head and neck radiotherapy data, using image registration techniques and Machine Learning methods. The aim was to detect serious anatomical changes during patients' radiotherapy treatment sessions, as these could lead to low dosage to tumor and overexposure of surrounding healthy tissues, causing adverse side effects. In this direction, the weekly CBCT images taken during image-guided patient radiotherapy (IGRT) were aligned with the initial planning CT. The alignment was completed, firstly, with affine type transformations followed by elastic transformations. These transformations were used to transform the anatomical structures designed by clinicians to coincide with the patient's anatomical structures on the day of radiotherapy. In this way, the cancer volume and the parotid volume were calculated, as well as the percentage change after the end of each week of treatment, and the patients were divided into those who had severe anatomical changes after the 3rd week of treatment and those who did not present changes. The two patient classes were used to compute predictive models for the possible occurrence of anatomical changes in patients after the first week of treatment. For this purpose, image texture features were calculated for the anatomical structures of the tumor and the end of the first week of treatments. With those image features, a predictive model was constructed, able to accurately predict whether a patient can show severe anatomical changes after the 3rd week of treatments.Σε αυτή τη Διδακτορική Διατριβή ο σκοπός ήταν η ανάλυση ιατρικών δεδομένων ακτινοθεραπείας, ασθενών με καρκίνο κεφαλής και τραχήλου, με χρήση τεχνικών ευθυγράμμισης ιατρικών δεδομένων και μεθόδων Μηχανικής Εκμάθησης (Machine Learning). Στόχος ήταν να εντοπιστούν πιθανές σοβαρές ανατομικές μεταβολές κατά την διάρκεια των συνεδριών ακτινοθεραπείας των ασθενών, διότι αυτές μπορεί να οδηγήσουν σε λανθασμένη απόδοση της δόσης στον καρκινικό όγκο καθώς και σε υπερ-ακτινοβόληση των γύρω υγειών ιστών, προκαλώντας ανεπιθύμητες παρενέργειες. Προς αυτή την κατεύθυνση, σε πρώτο στάδιο ευθυγραμμίστηκαν οι εβδομαδιαίες CBCT εικόνες που λαμβάνονται κατά την καθοδηγούμενη από την εικόνα ακτινοθεραπεία ασθενών (IGRT), με την αρχική αξονική σχεδιασμού του πλάνου θεραπείας (planning CT). Η ευθυγράμμιση έγινε σε δύο στάδια, με το πρώτο να αφορά την ευθυγράμμιση με μετασχηματισμούς τύπου affine και το δεύτερο την ευθυγράμμιση με ελαστικούς μετασχηματισμούς. Οι εν λόγω μετασχηματισμοί χρησιμοποιήθηκαν για να μετασχηματιστούν οι αρχικά σχεδιασμένες, από τους κλινικούς ιατρούς, ανατομικές δομές, ώστε να συμπίπτουν με τις ανατομικές δομές του ασθενούς την ημέρα της συνεδρίας ακτινοθεραπείας. Με τον τρόπο αυτό έγινε υπολογισμός του όγκου του καρκίνου και του όγκου των παρωτίδων, καθώς και η ποσοστιαία μεταβολή αυτών μετά το πέρας κάθε εβδομάδας θεραπειών και οι ασθενείς χωρίστηκαν σε αυτούς που είχαν σοβαρές ανατομικές μεταβολές μετά την 3η εβδομάδα θεραπειών και σε αυτούς που δεν εμφάνισαν σοβαρές μεταβολές. Οι δύο κατηγορίες (κλάσεις) ασθενών χρησιμοποιήθηκαν ώστε να κατασκευαστούν προβλεπτικά μοντέλα σχετικά με πιθανή εμφάνιση ανατομικών μεταβολών σε ασθενείς από το τέλος της πρώτης εβδομάδας θεραπειών. Για τον σκοπό αυτό, υπολογίστηκαν για τις ανατομικές δομές του όγκου και των παρωτίδων, χαρακτηριστικά εικόνας από το τέλος της πρώτης εβδομάδας θεραπειών με βάση τα οποία κατασκευάστηκε προβλεπτικό μοντέλο, ικανό να προβλέπει με ακρίβεια εάν ένας ασθενής δύναται να εμφανίσει σοβαρές ανατομικές μεταβολές μετά την 3η εβδομάδα θεραπειών