Die Entstehung der pathologisch-anatomischen Befunde nach Hirnerschütterung in Abhängigkeit vom Gefäßnervensystem des Hirnes

Labyrinthine concussion: Historic otopathologic antecedents of a challenging diagnosis

OBJECTIVE

The term "labyrinthine concussion" has evolved to mean audiovestibular dysfunction in the absence of a temporal bone fracture (TBF). Despite a multitude of case descriptions of labyrinthine concussion, the precise pathophysiology remains poorly understood. Herein, we explore the historical otopathologic underpinnings of the diagnosis of labyrinthine concussion with a focus on the auditory pathway during the late 19th to the mid-20th centuries and conclude with a discussion of its contemporary relevance.

METHODS AND DATA SOURCES

A review of primary and secondary medical sources written in English, German, and French on otopathology labyrinthine concussion studies from the late-19th to the mid-20th centuries.

RESULTS

Around the turn of the 20th century, otopathologists identified histologic changes in the temporal bones of individuals that sustained head injury without TBFs. Based on these otopathologic findings in humans, early experiments investigating the pathophysiology of labyrinthine concussion were performed in animals through either the delivery of blows to the head or direct introduction of a pressure wave into the labyrinthine fluid. Collectively, otopathologists hypothesized that predominant mechanisms for labyrinthine concussion included inner ear hemorrhage, cochleovestibular nerve traction injury, direct damage from a labyrinthine fluid pressure wave, or vasomotor dysfunction.

CONCLUSION

Historical study shows a variety of inner ear pathologies potentially responsible for auditory dysfunction following head injury. Understanding the history and otopathology of labyrinthine concussion may help clinicians focus on new pathways toward novel research and improved patient care.

[Cytology, lactate dehydrogenase, and creatine kinase in CSF in mild head injuries (author's transl)]

Cytology, lactate dehydrogenase, and creatine kinase in cerebrospinal fluid were investigated 6-72h after mild head injuries in 59 patients aged 16-49 years. Significant differences were not found in creatine kinase. Lactate dehydrogenase, however, was significantly more elevated in mild cerebral contusions compared with concussions 24h after head injury. Monocytoid reaction in cerebrospinal fluid was significantly more distinct in mild contusions compared with concussions 24h after impact. Large phagocytes were rarely found in concussions and were not traceable 48h after impact. Large phagocytes, however, were found in 50-55% of the mild contusions 48-72h after head injury. Siderophages were found only in contusions (16.5-35%), 48-72h after impact). The optimal time for lumbar punction is 24h after head injury.

[Autoradiographic investigations in repeated experimental brain concussion (author's transl)]

Single brain concussion in rabbits causes an increased proliferation of glial and mesenchymal cells. Repeated experimental concussions in rabbits (3 times at intervals of 24 h) led to an increased incorporation of H3-thymidine in glial and mesenchymal cells with a maximum at 48 h after the third concussion. This is interpreted as an indication of increased cell proliferation. The first and the second concussion did not cause a comparable reaction, thus suggesting that concussions may inhibit DNA synthesis under the conditions of our experimental setup. When the concussions were induced at an interval of 48 h the result was different: 48 h after each concussion we found an increase of labeled cells compared with the controls. After the second concussion the reaction was still more enhanced compared with the reaction following the first concussion. In contrast to this the number of labeled cells after the third concussion was significantly decreased compared with those after the second one. Parallels with pugilistic encephalopathy are discussed.

Diffuse degeneration of the cerebral white matter in severe dementia following head injury

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