ABSTRACT
Implantable bone conduction hearing systems are intended for patients with a conductive or mixed hearing loss, in whom other treatment options do not provide sufficient benefits or are contraindicated. In general, they are called BAHDs (bone-anchored hearing devices) and they transform acoustic energy into vibrations transferred by a titanium implant through cranial bones to cochlea and fluids of the inner ear. The implantable bone conduction hearing systems are classified as passive and active based on the location of the vibration unit. The review describes the basic types of passive systems, their advantages and disadvantages. Special attention is paid to the Bonebridge active bone conduction system which represents a state-of-the-art, efficient and patient-friendly treatment method that removes the disadvantages of passive implantable systems.
Subject(s)
Bone Conduction , Hearing Aids , Hearing Loss, Conductive , HumansABSTRACT
Head and neck squamous cell carcinoma is one of the most aggressive tumours and is typically diagnosed too late. Late diagnosis requires an urgent decision on an effective therapy. An individualized test of chemosensitivity should quickly indicate the suitability of chemotherapy and radiotherapy. No ex vivo chemosensitivity assessment developed thus far has become a part of general clinical practice. Therefore, we attempted to explore the new technique of coherence-controlled holographic microscopy to investigate the motility and growth of live cells from a head and neck squamous cell carcinoma biopsy. We expected to reveal behavioural patterns characteristic for malignant cells that can be used to imrove future predictive evaluation of chemotherapy. We managed to cultivate primary SACR2 carcinoma cells from head and neck squamous cell carcinoma biopsy verified through histopathology. The cells grew as a cohesive sheet of suspected carcinoma origin, and western blots showed positivity for the tumour marker p63 confirming cancerous origin. Unlike the roundish colonies of the established FaDu carcinoma cell line, the SACR2 cells formed irregularly shaped colonies, eliciting the impression of the collective invasion of carcinoma cells. Time-lapse recordings of the cohesive sheet activity revealed the rapid migration and high plasticity of these epithelial-like cells. Individual cells frequently abandoned the swiftly migrating crowd by moving aside and crawling faster. The increasing mass of fast migrating epithelial-like cells before and after mitosis confirmed the continuation of the cell cycle. In immunofluorescence, analogously shaped cells expressed the p63 tumour marker, considered proof of their origin from a carcinoma. These behavioural traits indicate the feasible identification of carcinoma cells in culture according to the proposed concept of the carcinoma cell dynamic phenotype. If further developed, this approach could later serve in a new functional online analysis of reactions of carcinoma cells to therapy. Such efforts conform to current trends in precision medicine.
