[Preauricular mass following tympanoplasty]. / Präaurikuläre Raumforderung nach Tympanoplastik.

A 42-year-old man presented with a preauricular subcutaneous pulsating node which had appeared a few weeks after a middle ear operation. CT angiography revealed an aneurysm of the superficial temporal artery. The diagnosis was histologically confirmed after surgical resection of the finding. This is the first description of an aneurysm of the superficial temporal artery as a rare complication of a tympanoplasty. In the presented case, the aneurysm must have been caused either by the surgical trauma of the endaural tympanoplastic incision or the sharp retractors.

Effect of movements on the electrodermal response after a startle event.

OBJECTIVES: In this work the effect of quasi-stationary movements on the electrodermal activity (EDA) after a startle event has been investigated and evaluated. In previous EDA research there is a discrepancy between the use of controlled environment studies and daily life surveys. This paper aims to address this by expanding the knowledge about EDA in real life applications. METHODS: A minimally obtrusive body-worn measurement device was designed and produced that simultaneously records EDA and finger movements. During this study, five subjects walked at different speeds and listened to startling sound events. The EDA response to these startle events was analyzed for different walking speeds using crosscorrelograms and cumulative frequency plots. RESULTS: The measured response to the startle event is consistent with the signal characteristics described in the literature. The results show that the faster a person is walking the more the signal property of the phasic part of the EDA is approaching a uniform distribution. However, even at a walking speed of 6 km/h the effect of the startle event is statistically still visible in the EDA (p < 0.05). CONCLUSIONS: The presented work offers a good understanding of the EDA while walking at different speeds. Although the artefacts evoked by walking cannot be determined directly, information on the movement can be useful. Depending on the walking speed a measurement about the reliability of peak detection could be introduced.

Matrix metalloproteinases 2 and 9 in the cochlea: expression and activity after aminoglycoside exposition.

The matrix metalloproteinases (MMPs) are a family of proteins involved in the remodelling and homeostasis of the extracellular matrix. These proteases have been well studied in the retina and the brain, marking their importance in neuronal cell survival and death [Chintala (2006) Exp Eye Res 82:5-12; Candelario-Jalil et al. (2009) Neuroscience 158:983-994]. The neuroepithelia of the eye and the inner ear share common characteristics. Therefore, we hypothesized that MMPs could play a similar role in the cochlea as described in the retina. We focused on the localization and function of MMP-2 and MMP-9 in the cochlea, by determining their expression and activity under normal conditions and after cochlear damage via aminoglycoside exposition. We examined their expression in 5-day-old Wistar rat cochleas by RT-PCR, real-time PCR, and Western blot. We used immunohistochemistry to investigate their location in the cochleas of adult C57BL/6 mice. We also determined whether or not the exposure of the organs of Corti to aminoglycosides would change MMP-2 and MMP-9 expression patterns. Western blotting identified MMP-2 and MMP-9 in neonatal spiral ganglion, stria vascularis, and to a lesser extent the organ of Corti. Neonatal mRNA expression of MMP-2 was approximately equivalent in all three tissues, while MMP-9 mRNA was highest in spiral ganglion. Immunohistochemistry showed MMP-2 primarily in adult spiral ganglion neurons and inner hair cells, while MMP-9 was found mainly in spiral ganglion neurons, inner hair cells and supporting cells. Organs of Corti treated with gentamicin for 24 h showed an upregulation of MMP-2 and MMP-9 proteins, but did not show a significant upregulation of mRNA expression 3, 6, 12, 24, and 36 h after gentamicin exposure. Inhibition of MMP activity in organs of Corti incubated with an MMP inhibitor in organotypic cultures resulted in hair cell death-suggesting that a basal level of MMP activity is required for hair cell survival.