Tino Just

Noise Exposure of the Inner Ear During Drilling a Cochleostomy for Cochlear Implantation

Objectives: Inserting an electrode array into the cochlea may cause inner ear trauma, which has to be minimized, particularly in cochlear implant patients with substantial residual hearing. Another potential inner ear trauma has, to a large extent, been neglected so far: the acoustic trauma that can occur during cochleostomy using different techniques. In this study, the noise exposure of the inner ear during the drilling procedure was re‐evaluated. In experiments on temporal bones, quantitative measurements of sound pressure level (SPL) were carried out while a cochleostomy for cochlear implantation was drilled.

Cephalic phase insulin release in healthy humans after taste stimulation

In humans little is known as to whether taste solutions applied to the tongue elicit cephalic phase insulin release (CPIR). The aim of this study was to re-examine if any effect of different taste solutions on CPIR occurs. Under fasting conditions healthy human subjects sipped, and washed out their mouths with eight taste solutions (sucrose, saccharin, acetic acid, sodium chloride, quinine hydrochloride, distilled water, starch, and sodium glutamate) for 45 s and spat them out again. The taste stimuli were not swallowed; they were applied in a randomized order, each on a separate day. Blood collection for determination of plasma glucose and plasma insulin concentrations was performed 3 min before and 3, 5, 7 and 10 min after taste stimulation. Ratings of quality, intensity and hedonic characteristics were also obtained. A significant increase of plasma insulin concentration was apparent after stimulation with sucrose and saccharin. In conclusion, the current data suggest that the sweeteners sucrose and saccharin activate a CPIR even when applied to the oral cavity only.

Contact Endoscopic Comparison of Morphology of Human Fungiform Papillae of Healthy Subjects and Patients with Transected Chorda Tympani Nerve

Background: The chorda tympani nerve (CTN) carries gustatory fibers from taste buds of fungiform papillae (fPap) of the anterior portion of the tongue. Accordingly, middle ear surgery with transection of the CTN may result in gustatory impairment. With use of contact endoscopy, the present study aimed to compare number and shape of fPap and subepithelial vessel formation in patients after CTN transection with that of healthy controls.

Confocal microscopy of the peripheral gustatory system : Comparison between healthy subjects and patients suffering from taste disorders during radiochemotherapy

Objectives: Laser‐scanning microscopy (LSM) was used to compare taste buds and epithelia of fungiform papillae of healthy subjects with those of patients suffering from taste disorders during/after radiochemotherapy (RCT). Aim of the study was to investigate effects responsible for taste loss at a microscopic level.

Intra-operative application of optical coherence tomography with an operating microscope

OBJECTIVE To introduce the use of optical coherence tomography with an operating microscope for intra-operative evaluation of the human larynx. METHODS A specially equipped operating microscope with integrated spectral domain optical coherence tomography apparatus was used during microlaryngoscopy. RESULTS Technical improvements in optical coherence tomography equipment (e.g. pilot beam, variable focal distance, improved image quality and integration into an operating microscope) have enabled greater sensitivity and imaging speed and a non-contact approach. Spectral domain optical coherence tomography now enables a better correlation between optical coherence tomography images and histological findings. With this new technology, the precision of biopsy can be improved during microlaryngoscopy. CONCLUSIONS Use of this new optical coherence tomography technology, integrated into an operating microscope, enables the surgeon to define the biopsy site location and resection plane precisely, while the optical zoom of the operating microscope can be used over the complete range.

In vivo observation of papillae of the human tongue using confocal laser scanning microscopy.

The aim of this investigation was to visualize the epithelial structures of the tongue using confocal laser scanning microscopy (LSM). The human tongue epithelium of 28 healthy subjects, aged 21–67 years, mean age 38 years, 14 women and 14 men, was examined in vivo by LSM. Using LSM, a combination of the Heidelberg Retina Tomograph HRT II and the Rostock Cornea Module, up to 800-fold magnifications were obtained. On the tongue surface both filiform and fungiform papillae and their taste pores were easily identified. The epithelium of the tongue with its subcellular structures could be observed up to a depth of 50 µm, cellular structures up to 150 µm and subepithelial vessels up to 300 µm. Additionally the papillary crests and blood flow were visible. Confocal LSM seems suitable for noninvasive in vivo examination of the tongue. The hydraulic z scan, the manual start setting and the measurement of the depth allow a clear classification of the observed structures.

Third window vibroplasty: an alternative in surgical treatment of tympanosclerotic obliteration of the oval and round window niche.

Objective: To describe a new technique in surgical treatment of obliterative tympanosclerosis by applying a floating mass transducer (FMT) to a third window. Patient: A 64-year-old woman with a severe combined hearing loss due to tympanosclerosis received a third window vibroplasty. Intervention: A mastoidectomy and a posterior tympanotomy via the large facial recess were performed. The promontory was exposed by a transcanal approach. The third window was performed anterior inferior to the round window. The membranous cochlea was left intact. The FMT was gently pushed into the perichondrium-coated cochlear window. All other surgical steps were the same as in conventional FMT application. Results: Preliminary data of this report reveal that vibroplasty with coupling of the FMT directly to a third window leads to similar audiological results compared with the conventional coupling of the FMT on the round window niche. Conclusion: The presented case demonstrates the applicability of a third window vibroplasty in obliterative tympanosclerosis. Further studies will show if our assumption of a reduced risk for inner ear trauma is justified or not.

Optical coherence tomography as an orientation guide in cochlear implant surgery

Conclusion: With optical coherence tomography (OCT) it is basically possible to reveal parts of the cochlear morphology without opening its enveloping membranes. Thus, it may serve as a helpful guide for the surgeon to localize the scala tympani precisely before opening the fluid-filled inner ear to insert the electrode array. Objective: To improve anatomical orientation in cochlear implant surgery before definitively opening the fluid-filled inner ear. The question was whether a new imaging technique, OCT, might provide information about the site of the underlying inner ear structures (scala tympani, scala vestibuli) and could, consequently, guide the surgeon towards the scala tympani. Materials and methods: In a preliminary study, OCT was carried out on human temporal bone preparations, in which a cochleostomy (‘fenestration’) was performed leaving the endosteum and the fluid-filled inner ear intact. OCT was applied via a prototype of a specially equipped operating microscope. The mode of OCT used in this context was spectral-domain (SD)-OCT. Results: On scans, which can be read analogous to B-mode sonography, OCT provides information about structures on the inner surface of the partly exposed but still intact membranous cochlear lining – such as scala tympani or scala vestibuli.

Pressure changes in the human middle ear without opening the eustachian tube.

Conclusion. By means of a direct, though non-invasive experiment on healthy humans we could demonstrate that middle ear (ME) pressure decreases when the eustachian tube (ET) does not open. Thus with a very simple method the basic theory of continuous gas loss from the ME into the circulation and the replenishment of the loss through the ET could be validated. Objectives. To record changes in ME pressure over a period of time in normal human ears, while the ET is kept closed. Subjects and methods. On-line tympanometry was carried out in three subjects, who refrained from swallowing for 20–120 min. Results. During the time when the ET was kept closed by refraining from swallowing, tympanometric monotonous pressure decrease was recorded. Once the tested subject could not refrain from swallowing any longer and swallowed again, ME pressure equalized immediately.

Optical coherence tomography allows for the reliable identification of laryngeal epithelial dysplasia and for precise biopsy: a clinicopathological study of 61 patients undergoing microlaryngoscopy.

A newly developed microscope‐based spectral‐domain optical coherence tomography (SD‐OCT) device and an endoscope‐based time‐domain OCT (TD‐OCT) were used to assess the inter‐rater reliability, sensitivity, specificity, and accuracy of benign and dysplastic laryngeal epithelial lesions.