Etiology-Specific Mineralization Patterns in Patients with Labyrinthitis Ossificans

The Conundrum of Labyrinthitis Ossificans: An Etiology-Based Case Comparison and Review of Literature

Labyrinthitis ossificans is the formation of pathological new bone within the membranous labyrinth of the inner ear due to various local and systemic pathologies. Most commonly it occurs as a sequelae of meningitis spreading to the labyrinth, from the subarachnoid space via the cochlear aqueduct and the internal auditory canal. We are comparing three different etiological presentations of labyrinthitis ossificans; namely, tympanogenic, meningitic, and traumatic, together with their management in the light of recent advances.

Inner ear modifications in Dar-es-Soltane II H5 (Morocco): A case of labyrinthitis ossificans

OBJECTIVE

This paper presents the inner ear modifications in Dar-es-Soltane II H5, an Aterian fossil possibly dated to 100 ka.

MATERIAL

The remains consist of a large portion of the cranium including the face, the left frontal and temporal bones, part of the left parietal bone and greater wing of the sphenoid.

METHODS

The bony labyrinth anatomy was investigated on existing micro-CT data acquired by the MPI-EVA.

RESULTS

The observation of micro-CT sections revealed a partial filling of the semi-circular canals that raises question about its origin. A careful examination of the micro-CT sections shows that the elements present in the semicircular canals were denser than the sediments observed in other regions and cavities of the temporal bone.

CONCLUSIONS

The current evidence suggests a pathological origin of this condition with partial ossification of the membranous labyrinth. The differential diagnosis indicates a case of labyrinthitis ossificans in its early stages.

SIGNIFICANCE

This pathological condition can be responsible for permanent hearing loss and is associated with dizziness and vertigo. Along with the Singa skull, Dar-es-Soltane II H5 represents one of the oldest known cases of labyrinthitis ossificans.

LIMITATIONS

The early stage of disease and the absence of the right temporal bone limit conclusions about the degree of disability of the individual and their dependence on the rest of the group.

SUGGESTIONS FOR FURTHER RESEARCH

To carry out a paleopathological study of all the fossils from Dar-es-Soltane II.

Diagnosis and management of intralabyrinthine schwannoma: case series and review of the literature

Intralabyrinthine schwannoma (ILS) is a rare benign tumor affecting cochlear and vestibular nerves, whose symptoms are generally unspecific and frequently responsible for a late diagnosis. Radiological examinations, with particular reference to magnetic resonance imaging (MRI), represent the only diagnostic technique to identify ILS. On computed tomography ILS can only be indirectly suspected by the presence of surrounding bone remodeling, whereas MRI provides direct visualization of the neoplasm as a filling defect within the labyrinth with vivid contrast enhancement. At the same time, MRI is also helpful in defining ILS anatomical extension into adjacent structures and in planning therapeutic management. Here we report three representative cases of ILS with new pictorial imaging features to improve ILS early detection and optimize subsequent therapeutic management.

The Forgotten Second Window: A Pictorial Review of Round Window Pathologies

The round window serves to decompress acoustic energy that enters the cochlea via stapes movement against the oval window. Any inward motion of the oval window via stapes vibration leads to outward motion of the round window. Occlusion of the round window is a cause of conductive hearing loss because it increases the resistance to sound energy and consequently dampens energy propagation. Because the round window niche is not adequately evaluated by otoscopy and may be incompletely exposed during an operation, otologic surgeons may not always correctly identify associated pathology. Thus, radiologists play an essential role in the identification and classification of diseases affecting the round window. The purpose of this review is to highlight the developmental, acquired, neoplastic, and iatrogenic range of pathologies that can be encountered in round window dysfunction.