EarBase

Temporal bone 3D reconstruction and analysis of endolymph volume in Meniere disease (2026)

Kanaris AA, Xiao AY, Biswas E, Lekovic GP, Go JL, Cai SS, Ishii M, House JW, Lopez IA, Ishiyama GP, Ishiyama A.

This study investigated endolymph volumes in patients with Meniere's disease compared to age-matched controls using 19 archival human temporal bones. Endolymph volumes within the vestibule and cochlea were significantly higher in Meniere's disease specimens, providing objective anatomic reference values directly compared with MRI studies of endolymphatic hydrops.

Changes in the neurovascular unit in Meniere's Disease (2025)

Curry SD, Lopez IA, Ishiyama G, Ishiyama A.

This study found a significant 50% loss of spiral ganglion neurons among patients with Meniere's disease compared with age-matched controls, along with a corresponding decrease of blood vessels. Results suggest that neurovascular unit interaction may be critical to preserve spiral ganglion neurons in Meniere's disease.

Histopathology of opioid-induced sensorineural hearing loss: a case report (2025)

Wong EC, Danielian A, Lopez I, Ishiyama A, Ishiyama G.

The first temporal bone histopathologic study of a patient with opioid-induced sensorineural hearing loss. Findings showed remarkable loss of sensory and supporting cells in the organ of Corti, with relative preservation of spiral ganglion neurons, suggesting cochlear implantation as the treatment of choice in irreversible cases.

Morphometric measurements of the incomplete partition Type II (IP-II) cochlea and implications on cochlear implantation (2025)

Xiao A, Saad M, Korte GO, Fujiwara R, Sennaroglu L, Lopez IA, Ishiyama G, Ishiyama A.

Three-dimensional reconstructions of IP-II cochleae from 11 archival human temporal bones provided morphometric measurements of critical structures that inform electrode selection and insertion strategies for cochlear implantation in this complex malformation.

Expression of TGFb-1 and CTGF in the implanted cochlea and its implications on new tissue formation (2024)

Xiao A, Lopez IA, Ishiyama G, Ishiyama A.

The first study investigating expression of two profibrotic cytokines—TGFβ-1 and CTGF—in the human implanted cochlea. Findings provide a better understanding of the mechanism behind new tissue formation and may help develop future mitigating interventions.

Greater Cochlear Damage in Otogenic Versus Meningogenic Meningitis: Hearing Rehabilitation Implications (2026)

Tavares MP, Pauna HF, Monsanto RDC, Keskin-Yilmaz N, Almeida BLD, and Penido NO.

This study found that both otogenic and meningogenic infection routes lead to reduction in auditory and vestibular neurons, but the otogenic route causes significantly more severe damage to cochlear hair cells, emphasizing the importance of early audiological screening for timely rehabilitation.

Abnormalities of the Facial Nerve in Temporal Bones With Inner Ear Malformations (2025)

Shimura T, Alp J, Keskin-Yilmaz N, Schuster AK, Rajan D, Paparella MM, Cureoglu S, Monsanto RDC.

Analysis of temporal bone specimens identified anatomical abnormalities in the facial nerve in patients with bony inner ear malformations, including hypoplastic nerves, narrow facial recesses, and abnormal nerve positioning, all of which complicate the traditional surgical approach for cochlear implants.

Otosclerosis and the evolution of stapes surgery: A historical and otopathological study (2025)

Rajan D, Cureoglu S, Adams ME, Monsanto RDC.

This study examines the historical progression of otosclerosis surgery—from early stapes mobilization and fenestration to modern stapedectomy and stapedotomy—by analyzing successful and unsuccessful temporal bone specimens, highlighting how advances in otopathology have been essential in refining surgical interventions.

Hyperplastic growth, not hydrostatic distension, in endolymphatic hydrops in humans challenges the classic view of Meniere's disease (2025)

Bryton C, Correa DM, Bächinger D, et al.

Using 3D histological reconstruction, machine-learning-based cell analysis, and molecular labeling in human temporal bone specimens, this study found no structural evidence for pressure-induced stretching of inner ear membranes. Instead, affected tissues showed a marked increase in cell number—up to 4–7 times higher than normal—suggesting the membranes expand through active cell proliferation. These findings fundamentally challenge the classic pressure-based model of Meniere's disease.

Integrated histology and molecular profiling of postmortem human auditory and vestibular organs via a poly (methyl methacrylate)-based workflow (2025)

Bächinger D, Peyton B, Neubauer J, et al.

This study introduces a new method to study the human inner ear at both microscopic and molecular levels. The novel workflow reduces processing time from over a year to less than two months and lowers costs by more than 90%, while maintaining high-quality tissue preservation. This advance opens the door to studying the cellular and genetic mechanisms underlying hearing and balance disorders directly in human specimens.

Age-related stereocilia pathology in the human cochlea (2022)

Wu PZ, Liberman LD and Liberman MC.

This study used immunostaining to reveal sensory cells and their stereocilia from individuals aged 21–71 years. Widespread stereocilia loss and fusion on surviving inner and outer hair cells was found in the high-frequency regions of older ears. Results suggest that therapies to repair hair bundles, rather than regenerating missing hair cells, could be useful in the treatment of age-related hearing loss.

Primary neural degeneration in the human cochlea: evidence for hidden hearing loss in the aging ear (2019)

Wu P, Liberman LD, Bennett K, De Gruttola V, O'Malley JT and Liberman MC.

This study of temporal bone specimens from normal individuals aged 0–89 years showed, for the first time, that there is monotonic loss of cochlear nerve fibers innervating surviving inner hair cells as we age. On average, 50% of the peripheral axons of cochlear nerve fibers had disappeared throughout the cochlear spiral by age 65, despite minimal loss of the sensory cells they innervate. These results suggested that this type of primary neural degeneration may be a major contributor to the problems with speech discrimination associated with age-related hearing loss.

A case of calcification discovered within the membranous labyrinth during resection of a vestibular schwannoma (2025)

Ahmad SA, Zawitoski H, Hiel H, Balhi Y, Lauer A, Kaufman A, Ward BK.

This case report describes case of a patient with cystic vestibular schwannoma and longstanding hearing loss and balance problems in whom calcification was found in the membranous labyrinth after transtemporal labyrinthectomy. MRI showed the tumor, and later imaging review revealed a preoperative ring of calcification that matched the surgical findings. Post-surgical pathologic and immunohistochemical analysis revealed abnormalities in the inner ear structures, indicating that membranous labyrinth calcification may be a sign of underlying inner ear disease that deserves further study.

Labyrinthine sequestrum: otopathologic description of a rare condition in a case from the temporal bone histopathology archives (2025)

Balhi Y, Nauen D, Galaiya D, Lauer A, Ward BK.

This postmortem review of H & E stained human temporal bone slides describes an unusual case of labyrinthine sequestrum (LS), after chronic suppurative labyrinthitis. LS is marked by extensive ossification and destruction of the otic capsule's global architecture, and it is distinctly characterized by the presence of an infected bone sequestrum, which perpetuates a chronic infectious process within the temporal bone. This case shows evidence of severe chronic inflammation and extensive new bone formation in the left middle and inner ear. The cochlea, vestibule, and semicircular canals show widespread fibro-inflammatory tissue, ossification, and structural destruction, including loss of key cochlear membranes and many spiral ganglion cells. The cochlear nerve is not visible, while the facial nerve appears preserved, suggesting advanced inner ear damage with major distortion of the otic capsule and labyrinth.

Harvest of vestibular end-organs under physiologic conditions during labyrinthectomy (2024)

Andresen NS, Hiel H, Graham CJ, Balhi Y, Carey JP, Lauer AM, Ward BK.

This paper describes a method for collecting intact human vestibular tissue during labyrinthectomy under near-physiologic conditions, preserving tissue quality for study. In a patient with Ménière’s disease, surgeons used endoscopic visualization and irrigation to harvest structures from the semicircular canals and utricle, then fixed and immunostained the tissue for microscopy. The results show preserved hair cells and neural structures, suggesting this approach can provide valuable fresh human inner ear tissue for studying otologic disease at the cellular level.

Otolith membrane herniation, not semicircular canal duct dilation, is associated with decreased caloric responses in Ménière's disease (2023)

Shen LL, Andresen NS, Chari DA, Pogson JM, Lauer AM, Rabbitt RD, Carey JP, Santos F, Ward BK.

This study examines why people with Ménière’s disease often have abnormal caloric test results but normal video head impulse testing, even though both assess the semicircular canal function using H&E stained temporal bone histology specimens, The study evaluated the semicircular canals for endolymphatic hydrops, which had been hypothesized to contribute to the dissociation, and found no evidence of duct dilation/hydrops. However, the otolith membrane can be seen herniating into the horizontal canal in most affected ears. This was strongly associated with reduced caloric responses. The study notes a potentially novel morphologic finding—smaller bony labyrinth cross-sectional diameters/areas in some Ménière’s ear canals compared to controls, suggesting relative size of the membranous duct to the bony canal rather than absolute size may be of importance.