Banca de QUALIFICAÇÃO: NATÁLIA CARASEK MATOS CASCUDO

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : NATÁLIA CARASEK MATOS CASCUDO
DATE: 29/01/2025
TIME: 18:00
LOCAL: Auditório 1 HUB-UnB
TITLE:

“Otopathology of the unilateral severe to profound hearing loss.”

KEY WORDS:

“Hearing loss, unilateral; otopathology; cochlea; spiral ganglion; organ of Corti.”

PAGES: 100
BIG AREA: Ciências da Saúde
AREA: Medicina
SUMMARY:

“Introduction: The impact of single-sided deafness for the patients has often been underestimated, as it was believed that the normal contralateral ear would compensate for the deficits of the other side. Nowadays it is known that a particularly increased effort is required to compensate for it in complex listening environments, leading to a reduced performance and an increased hearing handicap. Otopathology allows the study of diseases affecting the ear and it is the gold standard for evaluating intracochlear pathology, providing sensitive and specific identification of pathophysiological mechanisms. Objectives: To evaluate the histopathological findings of unilateral hearing loss and spiral ganglion cell counts, comparing them to the normal contralateral ear, and discussing implications of these findings for auditory rehabilitation. Methods: This study included 88 ears from 44 human subjects with a diagnosis of severe to profound unilateral hearing loss, from the Temporal Bone collection of the Otopathology laboratory of Massachusetts Eye and Ear Infirmary, with age ranging from 5 to 90 years old. Results: Within the study group, we included 6 different etiologies of hearing loss: sudden sensorineural hearing loss, Meniere’s disease, internal auditory canal tumors, chronic otitis media, stapes fixation and central nervous system disorders. The analysis for all causes showed that the loss of spiral ganglion cells was directly correlated with the loss of neural fibers (dendrites and axons) in all cochlear turns (p<0.001). Time did not show a direct correlation with neuronal loss in the spiral ganglion, which may indicate that even with a longer time of hearing deprivation, depending on the etiology, cochlear implantation may be an effective measure for rehabilitation. On the other hand, inner ear surgery was positively correlated with spiral ganglion atrophy (p=0.013), suggesting that rehabilitation intervention should be near or at the same surgical time, for a better prognosis. There is a correlation between unilateral loss and abnormalities of the organ of Corti (p<0.001), atrophy of the stria vascularis (p=0.002) and atrophy of the sensory organs (p<0.001). Evaluation of the ‘inner ear disease’ subgroup, excluding middle ear and central nervous system disorders, was positively correlated with some degree of hydrops (p<0.001), tectorial membrane abnormalities (p=0.001) and Scarpa’s ganglion atrophy (p=0.002). Inner ear surgery for this group was also correlated with spiral ganglion atrophy (p=0.008), and fibrosis (p=0.006) or ossification (p=0.005) of the cochlear lumen. In Meniere’s disease subgroup, there was no correlation between hydrops and the percentage of neuronal loss (versus control), supporting the theory that hydrops is in fact an adaptive mechanism to an inner ear insult rather than the cause of hearing loss. In the internal auditory canal tumor subgroup, spiral ganglion degeneration appears to occur regardless of the intervention, even when the approach was retrosigmoid. Conclusion: The multiple causes of unilateral hearing loss have different histopathological implications in the inner ear, which may reflect in different outcomes for auditory rehabilitation.” 

COMMITTEE MEMBERS:
Presidente - ***.299.221-** - FAYEZ BAHMAD JUNIOR - HUB
Externa à Instituição - FERNANDA FERREIRA CALDAS - IBO
Externa à Instituição - PAULIANA LAMOUNIER E SILVA DUARTE - CRER
Externo à Instituição - SADY SELAIMEN DA COSTA - UFRGS
Externa à Instituição - THAIS ABRAHÃO GOMES ELIAS - UNIFESP