Wideband acoustic immitance - Absorbance measurements in ears after stapes surgery.

OBJECTIVES: The study aimed to thoroughly assess absorbance in ears after stapes surgery (stapedotomy/stapedectomy) and how stapes surgery affects wideband acoustic immittance (WAI) metrics. METHODS: Eighty-three otosclerotic ears were analyzed pre- and postoperatively. The analysis comprised: air-bone gap (ABG) and WAI which included absorbance measurements, resonance frequency assessment, low frequency tympanometry and metrics derived from these measures. RESULTS: Absorbance after stapes surgery changed considerably compared to otosclerotic ears before surgery and also differed from normal ears. Absorbance after stapes surgery revealed two significantly different plot types: single-low-frequency-peak absorbance and two-peaks absorbance. Stapes surgery reduced resonance frequency in majority of operated ears and increased static compliance in low frequency tympanometry. Static compliance difference was directly proportional to ABG improvement at low frequencies. Postoperative ABG at 250 Hz and 500 Hz was most commonly correlated with postoperative WAI parameters. ABG improvement at 3000 Hz and 4000 Hz was directly proportional to absorbance difference at ~3000 Hz and 4000 Hz. It influenced the width of the postoperative absorbance by shifting both sides of the plot (negative values shift the points of the plot toward lower frequencies) with the correlation being more pronounced in postoperative two-peaks absorbance type ears. CONCLUSIONS: Absorbance by itself is not sufficient for assessment of changes to middle function following stapes surgery, and should be complemented with other measures. WAI measurements including absorbance, resonance frequency assessment, low frequency tympanometry, and metrics derived from these measures combined with air-bone gap provide insight into mechano-acoustic changes in the middle-ear system as a result of stapes surgery.

Wideband tympanometry and absorbance measurements in otosclerotic ears.

OBJECTIVES: This study aimed to assess absorbance using a thorough analysis of individual points of its plot in ears with intraoperatively confirmed otosclerosis. To the best of our knowledge, until recently no analyses have been performed that concerned the shape of an absorbance plot and a detailed analysis of its individual points. This study is the first to undertake such an issue. METHODS: A total of 77 otosclerotic ears were included in the study. Pure tone audiometry, low frequency tympanometry, and wide band tympanometry including absorbance were performed preoperatively. The average patients' age in the group was 43.49 years (standard deviation = 10.44). Individual points of absorbance plot were thoroughly analyzed. Parameters were analyzed, such as resonance frequency; number of peaks; maximum absorbance (Height); and plot Width at the following Heights: 1/3, 1/2, and 2/3 (Width1/3, Width1/2, Width2/3, respectively), as well as associated absorbance parameters and frequencies. RESULTS: Data analysis revealed five different types of absorbance plots. Numerous statistically significant differences regarding the parameters of individual points of the plots were found among the distinguished types. CONCLUSIONS: There are five types of absorbance plots in otosclerotic ears: type I, characterized by two distinct peaks, closely resembling normal ear absorbance plot; type II with a single distinct peak reaching high values of absorbance; type III with reduced absorbance for frequencies <2000 Hz; type IV with reduced absorbance for all frequencies; and type V with reduced absorbance for frequencies >2000 Hz. Absorbance measurements may play an important role in the diagnostics of otosclerosis; however, further research is necessary in this area. LEVELS OF EVIDENCE: 4 Laryngoscope, 129:E365-E376, 2019.

Ceruminous adenoma (ceruminoma) arising in a nevus sebaceus of Jadassohn within the external auditory canal of a 3 year-old boy - A case report.

Nevus sebaceus of Jadassohn is a congenital yellowish hairless skin lesion, mainly located on the head and neck. A common phenomenon is the coexistence of secondary tumors within the lesion. These are mainly benign tumors, the majority of which are trichoblastoma and syringocystadenoma papilliferum. A ceruminoma is a very rare tumor of the ceruminous glands located in the outer third of the auditory canal. It occurs almost exclusively in adults. We describe the case of a 3-year old boy diagnosed with ceruminous adenoma (ceruminoma) growing within a nevus sebaceus of Jadassohn.

Salt tolerance of barley induced by the root endophyte Piriformospora indica is associated with a strong increase in antioxidants.

The root endophytic basidiomycete Piriformospora indica has been shown to increase resistance against biotic stress and tolerance to abiotic stress in many plants. Biochemical mechanisms underlying P. indica-mediated salt tolerance were studied in barley (Hordeum vulgare) with special focus on antioxidants. Physiological markers for salt stress, such as metabolic activity, fatty acid composition, lipid peroxidation, ascorbate concentration and activities of catalase, ascorbate peroxidase, dehydroascorbate reductase, monodehydroascorbate reductase and glutathione reductase enzymes were assessed. Root colonization by P. indica increased plant growth and attenuated the NaCl-induced lipid peroxidation, metabolic heat efflux and fatty acid desaturation in leaves of the salt-sensitive barley cultivar Ingrid. The endophyte significantly elevated the amount of ascorbic acid and increased the activities of antioxidant enzymes in barley roots under salt stress conditions. Likewise, a sustained up-regulation of the antioxidative system was demonstrated in NaCl-treated roots of the salt-tolerant barley cultivar California Mariout, irrespective of plant colonization by P. indica. These findings suggest that antioxidants might play a role in both inherited and endophyte-mediated plant tolerance to salinity.