Influence of the pre- or postlingual status of cochlear implant recipients on behavioural T/C-levels.

INTRODUCTION: Previous auditory experience modifies the sensitivity of the auditory cortex to the afferent activity of the auditory pathways and may influence the threshold (T) and comfort (C) levels in patients receiving a cochlear implant (CI). Literature data on this particular topic is very scarce. OBJECTIVE: This study aimed to evaluate the differences in T/C-levels between pre- and postlingually implanted cochlear implant patients. METHODS: Retrospective case review in a quaternary otologic referral centre was performed. Data on the T/C-levels have been collected in 90 consecutive CI patients divided into 2 groups. Group 1 comprised 16 prelingually deaf children implanted between 8 months and 10 years of age. Group 2 comprised 74 postlingually deaf adults (average age of 62 years). All patients were users of the Nucleus 24RECA (Freedom, Contour Advance-of-Stylet electrode) cochlear implant. All measurements were performed at the fifth implant programming session at 4-6 months after surgery, when stable T/C thresholds have already been obtained. RESULTS: The behavioural C-levels present important and statistically significant differences between the pre- and postlingually implanted patients for all electrode contacts that could reach 30 CL. For the T-levels the observed differences were smaller and statistically insignificant for most electrode contacts. CONCLUSIONS: The previous auditory experience (pre- or postlingual deafness) seems to be an independent parameter influencing the T/C-levels in patients receiving a CI. Together with the electrode contact impedance and the contact position in the electrode array it can explain up to 37% of the variability in the definition of the C-levels. The fact that the stabilised C-levels measured 4-6 months postoperatively can be up to 30 CL higher in the prelingually deaf patients than in the postlingual ones results also in a much higher dynamic range observed in prelingual subjects. Therefore implant programming of the prelingual patients should be very cautious in order to avoid the risk of overstimulation.

Körner's septum (petrosquamosal lamina): the anatomical variant or clinical problem?

Körner's septum (KS) or petrosquamosal lamina is a bony lamina beginning at the articular fossa, extending above the middle ear, and running inferiorly and laterally to the facial nerve canal as it proceeds to the mastoid apex. This septum marks the junction of petrous and squamous bones. The paper presents details of the anatomical structure of KS, which is most often present at the level of the head of the malleus and/or the anterior semicircular canal. Attention is paid to embryological aspects of temporal bone development that lead to the formation of KS. Two imaging techniques most frequently used to diagnose KS are described, high resolution computed tomography (HRCT) and cone-beam computed tomography. Also presented is a case report of a 6-year-old patient suffering from chronic otitis media who developed a cholesteatoma due to presence of KS, illustrated with HRCT images and intraoperative capture. The authors describe diagnostic difficulties associated with this anatomical variant in the middle ear. The article also discusses the more frequent occurrence of this clinical problem in ears operated on due to chronic inflammation, retraction pocket or tympanosclerosis in comparison to healthy ears.

Frontal aslant tract projections to the inferior frontal gyrus.

BACKGROUND: Frontal aslant tract (FAT) is a white matter bundle connecting the pre-supplementary motor area (pre-SMA) and the supplementary motor area (SMA) with the inferior frontal gyrus (IFG). The purpose of the present study was to evaluate the anatomical variability of FAT. MATERIALS AND METHODS: Total number of fibres and the lateralisation index (LI) were calculated. We attempted to find factors contributing to the diversity of FAT regarding IFG terminations to the pars opercularis (IFG-Op) and to the pars triangularis (IFG-Tr). Magnetic resonance imaging of adult patients with diffusion tensor imaging (DTI) with total number of 98 hemispheres composed a cohort. V-shaped operculum was the most common (60.5%). RESULTS: Total number of FAT fibres had widespread and unimodal distribution (6 to 1765; median: 160). Left lateralisation was noted in 64.3% of cases and was positively correlated with total number of FAT fibres and the bundle projecting to IFG-Op (p < 0.01). LI correlated with total number of FAT fibres (r = 0.43, p < 0.01). FAT projected predominantly to IFG-Op (88.9%; 88 of 99). Only in 3 (3.1%) cases more fibres terminated in IFG-Tr than in IFG-Op. Total number of FAT fibres and number of fibres terminating at IFG-Op did not correlate with the ratio of fibre numbers: FAT/IFG-Op, FAT/IFG-Tr and IFG-Op/IFG-Tr (p > 0.05). The greater total number of fibres to IFG-Tr was, the higher were the ratios of IFG-Tr/ /FAT (r = 0.57, p < 0.01) and IFG-Tr/IFG-Op (r = 0.32, p = 0.04). CONCLUSIONS: Among the IFG, the major termination of FAT is IFG-Op. Whereas the IFG-Tr projection seems to be related to the expansion of the entire FAT bundle regardless of side, domination and handedness. Nevertheless, FAT features a significant anatomical variability which cannot be explained in terms of DTI findings.

Bilateral large vestibular aqueduct syndrome in an 11-year-old boy. Radiological and clinical findings.

Clinical observations supplemented with imaging examination show that the large vestibular aqueduct syndrome (LVAS) is a rare developmental anomaly of the inner ear, which leads to hearing loss. The authors present a case history, results of imaging examination (high resolution CT, MRI), results of hearing acuity examinations (tonal audiometry, otoacoustic emissions, brainstem auditory evoked potentials) and results of balance examinations (videonystagmography) in an 11-year-old boy suffering from deep mixed progressive hearing loss of the right ear due to head trauma. The aim of this paper is to specify the most typical clinical, radiological and anatomopathological manifestations of this pathology of the inner ear. The authors describe the diagnostic and identification difficulties associated with the mixed hearing loss observed in this case. The article also discusses the child's activity limitations, which should be taken into account once diagnosis of this rare labyrinthine pathology is established.

Anatomy and physiology of directional hearing.

The aim of the paper is to present the most important neuroanatomical and neurophysiological studies concerning the phenomenon of sound localisation in space by people. The author analysed the available literature concerning this topic. The article presents different theories explaining the phenomenon of sound localisation, such as interaural differences in time, interaural differences in sound intensity, interaural and monaural differences in phase and the anatomical and physiological basis of these processes. It also describes methods of measurement of disturbances in sound localisation which are used around the world and in Poland, also by the author of this work. The author lists a number of reports on the neurological causes of disturbances in sound localisation, especially the ones connected with vascular damage of the brain. The reports indicate that it is the temporal and parietal lobes that play the role of cortical centres of sound localisation. Also, it should be pointed out that even though having two ears indeed makes it possible for humans to localise sources of sounds, the process itself takes place in the brain.

Hyperbaric oxygen therapy in the treatment of complications of irradiation in head and neck area.

BACKGROUND AND PURPOSE: We have investigated the treatment results of hyperbaric oxygen (HBO2) to patients with radiation-induced tissue complications. MATERIAL AND METHODS: Eight patients (1.4%) from 548 with head and neck cancers treated surgically with post- or preoperative radiotherapy or radiotherapy alone in standard doses who developed postradiation complications (6 patients with laryngeal chondroradionecrosis, 1 patient with osteoradionecrosis of the temporal bone, and 1 patient with soft tissue radionecrosis) are presented. To evaluate radiation reactions occuring in the head and neck region, we used the Chandler grading system for classification of postradiation larynx injuries and SOMA/LENT score for classification of postradiation injuries of mucosa of upper aerodigestive tract. Grades I and II in those grading systems are expected side effects of radiation therapy, thus our cases were all in grades III and IV. The HBO2 was performed after failure of the conventional treatment (antibiotics, steroids, topical therapy). The number of HBO2 expositions was from 8 to 39 and the delay to therapy from 2 to 22 months. RESULTS: Symptoms resolved in all treated patients. Six patients with laryngeal chondroradionecrosis had no symptoms after therapy and in three of them after partial laryngectomy the decannulation was performed. In one patient with mucosal radionecrosis after total laryngectomy, the esophageal fistula was closed and in one patient with osteoradionecrosis of the temporal bone, wound debridement followed. CONCLUSION: The authors' experience supports the increasing clinical evidence that HBO2 is an effective adjunct therapy for treatment of complications of irradiation in head and neck area.

The effect of hyperbaric oxygen on nasal mucociliary transport.

Nasal mucociliary transport was measured in a group of 30 adult patients (eight women and 22 men; age range 21-78 years, mean 47.9 years) treated with hyperbaric oxygen (HBO) therapy and in a control group of 32 adult subjects (two women and 30 men; age range 20-50 years, mean 32.0 years) compressed in a hyperbaric chamber without oxygen therapy. The treated patients breathed 100% oxygen at 250 kPa pressure for 60 min. Subjects from the control group were compressed in the hyperbaric chamber at 250 kPa for 70 min. Nasal mucociliary transport was measured with the saccharin clearance test. After exposure to HBO, the nasal mucociliary transport time was significantly decreased by 26% (P < 0.01) and returned to the original value after 24 h (increased by 8.3%, P = 0.25). In the control group, compressed in air, there were no statistically significant changes. This study shows that simultaneous compression and pure oxygen cause an increase in nasal mucociliary transport. The mechanism of activation of mucociliary clearance is probably the increased oxygenation of blood plasma and enhancement of metabolism in ciliated epithelium.

A case of multisymptomatic relapsing polychondritis in a 22-year-old woman.

A case of multisymptomatic relapsing polychondritis in a 22-year-old woman. We report a case of a 22-year-old woman with relapsing polychondritis (RP)--a rare and little known systemic autoimmune disease characterised by episodic inflammation of cartilaginous structures (ear, nose, bronchi, trachea, larynx, ribs, cardiovascular system). This patient presents with a seven-year history, initiated by the saddle nose. The patient developed a multitude of symptoms: auricular chondritis, ocular symptoms, recurrent arthritis, respiratory complications (laryngotracheomalacia, bilateral vocal cord palsy), sensorineural hearing loss and enchondroma of the humeral bone. The examination of an auricle biopsy by an immunofluorescent method and a positive serum reaction from the patient to normal cartilage supported the immunological nature of relapsing polychondritis. Treatment consisted of orally administered prednisone and diaminodiphenylsulfone (Dapsone).

[Hyperbaric oxygen therapy as a method of treatment of laryngeal and pharyngeal radionecrosis]. / Hiperbaria tlenowa jako metoda leczenia zmian popromiennych gardla i krtani.

The authors described two cases of palatine tonsil carcinoma treated with surgery and subsequent radiation therapy after which occurred severe radionecrosis of the larynx, pharynx and oral cavity. These subjects were treated with hyperbaric oxygen therapy (HBO). Complete resolution of postradiation changes was observed. The authors described: 1) basic changes in the tissues caused by radiation therapy; 2) the mechanisms of healing activity of hyperbaric oxygen.

[Hypopharyngeal carcinoma in 24 years old female]. / Rak gardla dolnego u 24-letniej kobiety.

A case of multifocal squamous cell carcinoma of posterior wall of the hypopharynx in 24 year female was described. A course of the disease and treatment were presented. Despite radical combined therapy patient died 1,5 year after the tumor diagnosis.

[Noise from a car airbag as a cause of acute acoustic trauma]. / Wystrzal samochodowej poduszki powietrznej jako przyczyna urazu akustycznego.

A case of acute acoustic trauma in 32 year male, caused by a noise from car airbag, was described. The symptoms occurring directly after the airbag shot were tinnitus and hearing loss in right ear. Patient was admitted to ENT Clinic in Gdansk just after 5 months after an accident. Treatment--vasodilatators and oxygen hyperbaric therapy--was ineffective. Review of literature, concerning the side effects of car airbag shot, was made. A mechanism of airbag action was presented as a source of short time noise.

Culture and selection of somatic hybrids using an auxotrophic cell line.

Protoplast fusions between Nicotiana tabacum and N. paniculata and between N. tabacum and N. sylvestris were obtained by polyethylene glycol and Ca(NO3)2 treatment. The protoplasts of one parent originated from cell suspensions, while the protoplasts of the other originated from leaf mesophyll. The heterokaryons were detectable by their intermediate phenotype, namely the green chloroplasts from mesophyll and the dense cytoplasm from suspension cells. They were isolated with micropipettes immediately after fusion using a micromanipulator and were transferred into a protoplast suspension of an auxotrophic cell line serving as a nursery. This mutant is not able to utilize nitrate and had to be supplemented with amino acids. The somatic hybrids were selected by a stepwise reduction of the supplements, which caused the death of the mutant cell colonies, while the autotrophic somatic hybrids continued to grow. The hybrid character of the selected colonies was confirmed by isoenzyme investigations.

Induced mutants from dihaploid potatoes after pollen mother cell treatment.

Microspore mother cells of dihaploid Solanum tuberosum plants were mutagenically treated during the stage of meiosis. Mutagenesis was performed either by irradiation with x- or γ-rays or by the application of nitrosomethylurethane or methylnitronitrosoguanidine. Then, by use of the anther culture technique, 913 functional plants and 442 untreated control plants were regenerated. From the exposed plants seven distinct mutants could be isolated, predominantly chlorophyll deficient lines, while from the controls no clear-cut mutants arose. One mutant turned out to be photomorphogenetic in addition to having a chlorophyll defect. In addition to the production of mutants the treatments significantly increased the frequency of multicellular structure formation from microspores.

Comparison of single cell culture derived Solanum tuberosum L. plants and a model for their application in breeding programs.

The techniques of microspore and protoplast regeneration starting from dihaploid Solanum tuberosum plants has been improved to such an extent that the production of more than 2000 microspore derived A1 plant lines and of several hundred protoplast derived plantlets has become possible. Further, from the dihaploid Solanum species S. phureja the regeneration of microspores to plants, and from the species S. infundibuliforme, S. sparsipilum and S. tarijense the regeneration of protoplasts to calluses, has been achieved. The plants descending from the two single cell culture systems are compared with reference to phenotypic markers and economic qualities. Some principles characteristic for either microspore or protoplast derived plants are examined and their significance is discussed. The results are compiled into an extended analytical synthetic breeding scheme based on a stepwise reduction of the autotetraploid to the monohaploid level and a subsequent controlled combination to a new synthetic completely heterozygous tetraploid potato.