Insights Into Vestibulo-Ocular Reflex Artifacts: A Narrative Review of the Video Head Impulse Test (vHIT).

Video head impulse test (vHIT) artifacts are defined as spurious elements or disturbances in the recorded data that deviate from the true vestibulo-ocular reflex response. These artifacts can arise from various sources, encompassing technological limitations, patient-specific factors, or environmental influences, introducing inaccuracies in vHIT outcomes. The absence of standardized criteria for artifact identification leads to methodological heterogeneity. This narrative review aims to comprehensively examine the challenges posed by artifacts in the vHIT. By surveying existing literature, the review seeks to elucidate the multifaceted nature of artifacts arising from technological, patient-related, evaluator-related, and environmental factors.

Efficacy of Disinfection of Rigid Endoscope by Ethyl Alcohol 70%

Abstract Introduction Currently, there is no safe, affordable, and ecologically-sustainable guideline that helps prevent contamination through endoscopy. We evaluated the safety of intermediate-level disinfection with 70% ethyl alcohol (w/v) based on biological-load recovery from rigid endoscopes after nasal endoscopy. Objective To demonstrate the efficacy of 70% ethanol in disinfecting rigid endoscopes (REs) to reduce microbial growth in microbiological cultures. Methods After a nasal endoscopy examination, the endoscope was swabbed with gauze; this served as the positive-control sample. The standard operating procedure for intermediate-level disinfection with 70% ethyl alcohol (w/v) following prior cleaning was applied. The endoscope was again swabbed; this served as the experimental sample. The collected material from the endoscope was extracted from gauze pieces, filtered through a 0.22-μm cellulose membrane, and cultivated in different means of culture. Results The results revealed a significant difference between the positive-control and experimental groups regarding the presence of Streptococcus coagulase (-) (p < 0.001), Bacillus spp. (p <0.001), and Staphylococcus aureus (p = 0.001). These microorganisms were detected in the control group, but not in the experimental group. Conclusions Microorganisms were not recovered from the samples of the experimental group, demonstrating the efficacy and the germicidal action of 70% ethyl alcohol (w/v) as a means of achieving intermediate-level disinfection.

Efficacy of Disinfection of Rigid Endoscope by Ethyl Alcohol 70.

Introduction Currently, there is no safe, affordable, and ecologically-sustainable guideline that helps prevent contamination through endoscopy. We evaluated the safety of intermediate-level disinfection with 70% ethyl alcohol (w/v) based on biological-load recovery from rigid endoscopes after nasal endoscopy. Objective To demonstrate the efficacy of 70% ethanol in disinfecting rigid endoscopes (REs) to reduce microbial growth in microbiological cultures. Methods After a nasal endoscopy examination, the endoscope was swabbed with gauze; this served as the positive-control sample. The standard operating procedure for intermediate-level disinfection with 70% ethyl alcohol (w/v) following prior cleaning was applied. The endoscope was again swabbed; this served as the experimental sample. The collected material from the endoscope was extracted from gauze pieces, filtered through a 0.22-µm cellulose membrane, and cultivated in different means of culture. Results The results revealed a significant difference between the positive-control and experimental groups regarding the presence of Streptococcus coagulase (-) ( p < 0.001), Bacillus spp. ( p < 0.001), and Staphylococcus aureus ( p = 0.001). These microorganisms were detected in the control group, but not in the experimental group. Conclusions Microorganisms were not recovered from the samples of the experimental group, demonstrating the efficacy and the germicidal action of 70% ethyl alcohol (w/v) as a means of achieving intermediate-level disinfection.

Cochlear turns measurements in patients with meningitis: A histopathological study.

OBJECTIVE: To demonstrate the cochlear turns area changes among patients with a history of meningitis, through otopatologic study. METHODS: We performed an analysis of the area of the bony cochlear turns and the cochlear lumen of the horizontal sections containing the modiolus and the area of the basal turn at the level of round window, in temporal bones obtained from patients with a history of meningitis and compared to a nondiseased control group. RESULTS: The mean area of the bony walls and the lumen of all cochlear turns are reduced within the meningitis group. Patients who presented a time from the diagnosis of meningitis to death longer than 30 days had a significant reduction in the cochlear turns area, as compared to the control group. CONCLUSION: Future studies may further correlate audiologic outcomes, cochlear volume, and cochlear area among patients with meningitis.

Histopathological changes to the peripheral vestibular system following meningitic labyrinthitis.

OBJECTIVE: While cochlear ossification is a common sequalae of meningitic labyrinthitis, less is known about the effects of meningitis on peripheral vestibular end organs. Herein, we investigate histopathologic changes in the peripheral vestibular system and cochlea in patients with a history of meningitic labyrinthitis. METHODS: Temporal bone (TB) specimens from patients with a history of meningitis were evaluated and compared to age-matched controls. Specimens were evaluated by light microscopy and assessed for qualitative changes, including the presence of vestibular and/or cochlear endolymphatic hydrops, presence and location of inflammatory cells, new bone formation, and labyrinthitis ossificans; and quantitative changes, including Scarpa's ganglion neuron (ScGN) and spiral ganglion neuron (SGN) counts. RESULTS: Fifteen TB from 10 individuals met inclusion and exclusion criteria. Presence of inflammatory cells and fibrous tissue was found in 5 TB. Of these, evidence of labyrinthitis ossificans was found in 2 TB. In the peripheral vestibular system, mild to severe degeneration of the vestibular membranous labyrinth was identified in 60% of cases (n = 9 TBs). There was a 21.2% decrease (range, 3%-64%) in the mean total count of ScGN in patients with meningitis, compared to age-matched controls. In the cochlea, there was a 45% decrease (range, 25.3%-80.9%) in the mean total count of SGN compared to age-matched controls (n = 14 TBs). CONCLUSIONS: Otopathologic analysis of TB from patients with a history of meningitic labyrinthitis demonstrated distinct peripheral vestibular changes. Future research may help to delineate potential mechanisms for the observed otopathologic changes following meningitis. LEVEL OF EVIDENCE: N/A.

The Effect of Fibroblast Growth Factors in Grafted Fascia into the Vocal Fold of Rabbits

Abstract Introduction The human larynx is a very important organ for communication. Many conditions lead to scarring of the vocal folds, decreasing voice quality. Objective We aimed to determine whether fibroblast growth factors (FGFs) may influence tissue integration of grafted fascia into the vocal folds of an animal model. Methods This is an experimental animal study with 12 adult rabbits that were submitted to a grafting fragment obtained from superficial cervical fascia into the vocal fold lamina propria, bilaterally. The right vocal fold was injected with FGFs. The animals were sacrificed after 1 month or 12 months, depending on the group they were assigned to, and a histological analysis of their vocal folds was performed.We analyzed the histological changes (such as the presence of fibrosis and neovascularization) induced by the acute or chronic inflammatory reactions. Results The FGFs induced acute inflammatory changes in all animals after 1 month of the initial experiment. The presence of FGFs triggered more fibrosis than the expected due to the surgical procedure itself when compared with the control side of all animals after 12 months of the initial experiment. Conclusions Fibroblast growth factors alone do not represent a good therapeutic option in phonosurgery, since we observed higher levels of fibrosis in the vocal fold lamina propria. Further studies combining more substances may be necessary to elucidate the best option to be used in this kind of surgery. (AU)

The Effect of Fibroblast Growth Factors in Grafted Fascia into the Vocal Fold of Rabbits.

Introduction The human larynx is a very important organ for communication. Many conditions lead to scarring of the vocal folds, decreasing voice quality. Objective We aimed to determine whether fibroblast growth factors (FGFs) may influence tissue integration of grafted fascia into the vocal folds of an animal model. Methods This is an experimental animal study with 12 adult rabbits that were submitted to a grafting fragment obtained from superficial cervical fascia into the vocal fold lamina propria, bilaterally. The right vocal fold was injected with FGFs. The animals were sacrificed after 1 month or 12 months, depending on the group they were assigned to, and a histological analysis of their vocal folds was performed. We analyzed the histological changes (such as the presence of fibrosis and neovascularization) induced by the acute or chronic inflammatory reactions. Results The FGFs induced acute inflammatory changes in all animals after 1 month of the initial experiment. The presence of FGFs triggered more fibrosis than the expected due to the surgical procedure itself when compared with the control side of all animals after 12 months of the initial experiment. Conclusions Fibroblast growth factors alone do not represent a good therapeutic option in phonosurgery, since we observed higher levels of fibrosis in the vocal fold lamina propria. Further studies combining more substances may be necessary to elucidate the best option to be used in this kind of surgery.

Evidence against the mucosal traction theory in cholesteatoma.

OBJECTIVES: To investigate the distribution of ciliated epithelium in the human middle ear and its potential role in the formation of cholesteatoma. STUDY DESIGN: Comparative human temporal bone study. METHODS: We selected temporal bones from 14 donors with a diagnosis of cholesteatoma, 15 with chronic otitis media without retraction pockets, 14 with chronic otitis media with retraction pockets, 14 with cystic fibrosis (CF), and 16 controls. We mapped the distribution of the ciliated cells in the mucosal lining of the middle ear and tympanic membrane using three-dimensional reconstruction analysis, and counted the number of ciliated cells in the middle ear mucosa. RESULTS: Ciliated cells are extremely sparse in the epithelial lining of the lateral surface of the ossicles in the epitympanum and the medial surface of the tympanic membrane. Furthermore, there is a significant decrease in the number of ciliated cells in these areas in temporal bones with cholesteatoma, chronic otitis media, chronic otitis media with retraction pockets, and CF compared to controls. Ciliated cells most commonly are located at the hypotympanum and the Eustachian tube opening but not the tympanic membrane or epitympanum. CONCLUSION: The paucity of ciliated epithelial cells on the medial side of the tympanic membrane and the lateral surface of the ossicles in the epitympanum in cases with cholesteatoma and/or chronic otitis media do not support the mucosal migration theory of cholesteatoma formation. LEVEL OF EVIDENCE: NA. Laryngoscope, 128:1663-1667, 2018.

Evaluation of the Grafted Fascia in the Vocal Fold of Dogs: A Histologic Study.

INTRODUCTION: There is no consensus on the ideal graft for medialization surgery of the vocal folds in the literature. One of the most favorable proposals is the use of autologous fascia, which seems limited by the lack of information regarding the integration of grafted tissue. Our study aims to evaluate the degree of fully engrafted fascia integration in the vocal fold lamina propria of dogs. MATERIALS AND METHODS: Fourteen adult mongrel dogs that underwent intravenous general anesthesia were selected and kept under spontaneous ventilation. A fascia lata fragment of 4 cm2 was obtained from the right leg of each dog. The dogs underwent laryngoscopy; a 3 mm incision was made in the vocal process, next to the vestibular process, and the fascia was grafted into the right vocal fold. The left vocal fold was used as a control. The animals were divided into two groups: group A, evaluated after 2 months of the procedure, and group B, evaluated after 6 months of the procedure. Histologic analysis was made semiquantitatively regarding the presence of inflammatory reaction, fibrosis, and neovascularization. RESULTS: Our final studied group comprised 12 dogs. Microscopic examination of the larynx revealed the absence of any detectable inflammation in the incision site. The lamina propria of the grafted vocal fold showed identifiable compact, thick, and eosinophilic collagen bands. The surrounding tissue showed thin collagen bands with some organization, similar to the contralateral vocal fold. CONCLUSION: The grafted fascia integrates into the vocal fold lamina propria and seems not to cause inflammatory reaction response.

Changes in the inner ear structures in cystic fibrosis patients.

OBJECTIVE: Although prolonged use of antibiotics is very common in cystic fibrosis (CF) patients, no studies have assessed the changes in both cochlear and peripheral vestibular systems in this population. METHODS: We used human temporal bones to analyze the density of vestibular dark, transitional, and hair cells in specimens from CF patients who were exposed to several types of antibiotics, as compared with specimens from an age-matched control group with no history of ear disease or antibiotic use. Additionally, we analyzed the changes in the elements of the cochlea (hair cells, spiral ganglion neurons, and the area of the stria vascularis). Data was gathered using differential interference contrast microscopy and light microscopy. RESULTS: In the CF group, 83% of patients were exposed to some ototoxic drugs, such as aminoglycosides. As compared with the control group, the density of both type I and type II vestibular hair cells was significantly lower in all structures analyzed; the number of dark cells was significantly lower in the lateral and posterior semicircular canals. We noted a trend toward a lower number of both inner and outer cochlear hair cells at all turns of the cochlea. The number of spiral ganglion neurons in Rosenthal's canal at the apical turn of the cochlea was significantly lower; furthermore, the area of the stria vascularis at the apical turn of the cochlea was significantly smaller. CONCLUSIONS: Deterioration of cochlear and vestibular structures in CF patients might be related to their exposure to ototoxic antibiotics. Well-designed case-control studies are necessary to rule out the effect of CF itself.

A 3-D analysis of the protympanum in human temporal bones with chronic ear disease.

Eustachian tube dysfunction is believed to be an important factor to cholesteatoma development and recurrence of disease after surgical treatment. Although many studies have described prognostic factors, evaluation methods, or surgical techniques for Eustachian tube dysfunction, they relied on the soft tissues of its structure; little is known about its bony structure-the protympanum-which connects the Eustachian tube to the tympanic cavity, and can also be affected by several inflammatory conditions, both from the middle ear or from the nasopharynx. We studied temporal bones from patients with cholesteatoma, chronic otitis media (with and without retraction pockets), purulent otitis media, and non-diseased ears, looking for differences between the volume of the protympanum, the diameter of the Eustachian tube isthmus, and the distance between the anterior tympanic annulus and the promontory. Light microscopy and 3-D reconstruction software were used for the measurements. We observed a decrease of volume in the lumen of the four middle ear diseased ears compared to the control group. We observed a significant decrease in the volume of the protympanic space in the cholesteatoma group compared to the chronic otitis media group. We also observed a decrease in the bony space (protympanum space) in cholesteatoma, chronic otitis media with retraction pockets, and purulent otitis media compared to the control group. We found a correlation in middle ear diseases and a decrease in the middle ear space. Our findings may suggest that a smaller bony volume in the protympanic area may trigger middle ear dysventilation problems.

A three-dimensional analysis of the endolymph drainage system in Ménière disease.

OBJECTIVES/HYPOTHESIS: To measure the volume of the endolymph drainage system in temporal bone specimens with Ménière disease, as compared with specimens with endolymphatic hydrops without vestibular symptoms and with nondiseased specimens STUDY DESIGN: Comparative human temporal bone analysis. METHODS: We generated three-dimensional models of the vestibular aqueduct, endolymphatic sinus and duct, and intratemporal portion of the endolymphatic sac and calculated the volume of those structures. We also measured the internal and external aperture of the vestibular aqueduct, as well as the opening (if present) of the utriculoendolymphatic (Bast's) valve and compared the measurements in our three study groups. RESULTS: The volume of the vestibular aqueduct and of the endolymphatic sinus, duct, and intratemporal endolymphatic sac was significantly lower in the Ménière disease group than in the endolymphatic hydrops group (P <.05). The external aperture of the vestibular aqueduct was also smaller in the Ménière disease group. Bast's valve was open only in some specimens in the Ménière disease group. CONCLUSIONS: In temporal bones with Ménière disease, the volume of the vestibular aqueduct, endolymphatic duct, and intratemporal endolymphatic sac was lower, and the external aperture of the vestibular aqueduct was smaller as compared with bones from donors who had endolymphatic hydrops without vestibular symptoms and with nondiseased bones. The open status of the Bast's valve in the Ménière disease group could be secondary to higher retrograde endolymph pressures caused by smaller drainage systems. These anatomic findings could correlate with the reason that some patients with hydrops develop clinical symptoms, whereas others do not. LEVEL OF EVIDENCE: N/A Laryngoscope, 127:E170-E175, 2017.

Methods of Fat Tissue Processing for Human Vocal Fold Injection: A Systematic Review.

OBJECTIVES: We analyzed different methods used to process autologous fat tissues for vocal fold injection (VFI). VFI is a safe procedure that preserves the folds' original elasticity and vibration properties and rarely triggers foreign-body reactions, but is often a temporary treatment due to fat reabsorption. To avoid it, selecting a technique that provides as many viable implantable adipocytes as possible is mandatory. STUDY DESIGN: This is a systematic review. METHODS: Data were collected from PubMed, Embase, Ovid, and Cochrane Library. Authors systematically reviewed databases for papers on autologous fat tissue processing methods involving human injections in vocal folds and vocalization outcomes that evolved the acoustic analysis of the voice before and after the surgical procedure, independently of the follow-up time. RESULTS: Nine out of the 517 articles met selection criteria for analysis. No standardized technique was found. CONCLUSION: There is no standardized technique for processing fat tissue for vocal fold injection. Further research is needed to point out the best available technique.

Pathologic Changes of the Peripheral Vestibular System Secondary to Chronic Otitis Media.

OBJECTIVE: To evaluate the histopathologic changes of dark, transitional, and hair cells of the vestibular system in human temporal bones from patients with chronic otitis media. STUDY DESIGN: Comparative human temporal bone study. SETTING: Otopathology laboratory. SUBJECTS AND METHODS: To compare the density of vestibular dark, transitional, and hair cells in temporal bones with and without chronic otitis media, we used differential interference contrast microscopy. RESULTS: In the chronic otitis media group (as compared with the age-matched control group), the density of type I and type II hair cells was significantly decreased in the lateral semicircular canal, saccule, and utricle (P < .05). The density of type I cells was also significantly decreased in the chronic otitis media group in the posterior semicircular canal (P = .005), but that of type II cells was not (P = .168). The mean number of dark cells was significantly decreased in the chronic otitis media group in the lateral semicircular canal (P = .014) and in the posterior semicircular canal (P = .002). We observed no statistically significant difference in the density of transitional cells between the 2 groups (P > .1). CONCLUSION: The findings of our study suggest that the decrease in the number of vestibular sensory cells and dark cells could be the cause of the clinical symptoms of imbalance of some patients with chronic otitis media.

Evaluation of Audiometric Thresholds and Speech Perception Sentence Test in Adults and Elderly After Cochlear Implantation.

AIM: To compare the audiometric thresholds and speech perception sentence test, between two groups with bilateral post-lingual, severe to profound sensorineural hearing loss. METHODS: Retrospective and analytical study, with 59 patients divided into 2 groups (under 60 years and above 60 years old) implanted between May/2002 and February/2007. RESULTS: The first group (control) included 30 patients with a mean age of 44 years. The audiometric threshold value in this group was 26 dB, and the average value of speech perception test was 94%. The second group included 29 patients with a mean age of 69 years. The average audiometric threshold was 29 dB, and the average value of SPT was 90%. The Mann-Whitney U-test was considered significant (P<0.05) only for 6-8 KHz frequencies and for SPT. CONCLUSION: Both groups had excellent outcomes in audiometric and speech testing with the use of CI, but with a significantly better performance in the adult group.