Biomedical subjects

J Hartwein

Publications and source records attributed to J Hartwein.

At least 19 recordsLinked to original sources

PubMed1992

["Crown-cork tympanoplasty"--a method for complete reconstruction of the tympanic membrane].

The crowncorktympanoplasty is a technique for the total reconstruction of the tympanic membrane, recommended in cases of ear malformation, blunting-phenomena and total deficiency of the membrane caused by chronic otitis media. Autologous tragal composite graft is used for the myringoplasty. While the cartilage faces to the middle ear cavity, the overflapping perichondrium is layed on the bony meatal wall in the manner of a crowncork. 10 cases performed in the last two years are reported. In each one an intact tympanic membrane could be reached. In average, the ear bone gap could be reduced for 18.5, 17.5, 16.5 and 13.5 dB in the frequencies of 500, 1000, 2000 and 4000 Hz.

Adolescent↗

PubMed1992

[Ossification of the stapedius tendon as a rare cause of conductive hearing loss].

Ossification of the stapedial tendon is a very rare cause of conductive hearing loss. In addition to a review of the literature, two further cases of unilateral hearing impairment are reported. In both cases, division of the ossified tendon led to a complete disappearance of the middle-ear problem. Apart from middle ear malformations, infections of the middle ear may also give rise to ossification of the stapedial tendon.

Audiometry, Pure-Tone↗

PubMed1992

[Dose-finding study for hyperfractionated, accelerated radiotherapy plus simultaneous carboplatin administration in patients with locoregionally advanced head and neck cancer].

Therapy of large inoperable squamous cell-carcinomas of the head and neck is considerably problemful. Combined simultaneous radio-chemotherapy with carboplatin and radiotherapy with hyperfractionated accelerated radiation is small effective than conventional monofractionated radiotherapy alone and may reduce side effects. Aim of the following study was dosage optimisation of the applicated carboplatin.

Carboplatin↗

PubMed1992

[The acoustics of the open mastoid cavity (so-called "radical cavity) and its modification by surgical measures. I. Physical principles, experimental studies].

Up to now the importance of the outer ear for the sound transmission is nearly neglected in the otosurgical literature. Nevertheless, surgical procedures can cause severe alterations in the anatomy of the outer ear channel. Necessarily variables which take influence on the acoustic behaviour of the outer ear can get changed by these surgical manipulations. By means of in-situ measurements of the sound-pressure-level near the tympanic membrane the influence of the ear channel/mastoid cavity volume as well as of the size of the outer meatus on the resonance frequency is investigated. In a model of variable volume and several sizes of outer meatus there can be found that the course of resonance-caused sound-pressure augmentation depends on two determining factors: due to the physical-acoustical conditions (Helmholtz-resonator) the peak of the resonance-caused augmentation shifts to lower frequencies the smaller the outer meatus and the larger the volume of the channel/mastoid cavity. Viceversa, an augmentation of the external meatus and an obliteration of the cavity causes a higher resonance frequency. Within values for the volume and the meatal size as can be found in radical cavity surgery the resonance frequency varies in a wide range from 1260 up to 3175 Hz. There is no substantial influence on the amplitude of the sound-pressure augmentation. Measurements undertaken in a temporal bone specimen underline these results: as well as in the model alterations of cavity volume and meatal size lead to partial extensive shiftings of the resonance frequency.(ABSTRACT TRUNCATED AT 250 WORDS)

Acoustics↗

PubMed1992

[The acoustics of the open mastoid cavity (so-called "radical cavity") and its modification by surgical measures. II. Clinical studies].

The acoustic resonance of a severely altered outer ear channel (radical mastoid cavity) is investigated in a series of 18 patients who underwent revision surgery by means of in-situ measurements of the sound-pressure-level near the tympanic membrane. While the average volume of the open cavity differs from the normal ear channel for the factor 2.5, the size of the external meatus is--in average--only 20% larger. This leads to an average frequency in patients with open cavity of 1939 Hz, more than 1000 Hz less than in a series (n = 20) of normal ears (average resonance frequency: 2942 Hz). The altered acoustic behaviour of the open cavity leads to partial extensive discrepancies of the resonance-caused sound-pressure augmentation in the frequencies of 3 and 4 kHz, which are important for speech perception. The average difference is more than 10 dB (SPL). Proved surgical techniques of cavity obliteration and meatoplasty can lead to a nearly normalized acoustic behaviour of the outer ear in a statistic significant way. Due to these surgical procedures, an average postoperative resonance frequency of 2421 Hz could be reached in our patients. Especially, the resonance-caused sound-pressure augmentation in 3-4 kHz could nearly be equalized to such of a normal outer ear. Differences in the acoustic behaviour of the outer ear as can be found between patients with an open mastoid cavity and normal ears can almost be eliminated surgically.(ABSTRACT TRUNCATED AT 250 WORDS)

Acoustics↗

PubMed1992

[Histological studies of the behavior of the dentin ossicular prosthesis in the human middle ear].

The Dentine Ossicular Prosthesis (DOP)--introduced in the ENT-Department, University of Hamburg in 1986--has proved its worth clinically in more than 300 cases. In the meantime six of the prostheses had to be removed for various reasons. They had remained in the middle ear over a period between 2-5 and 47 months. The prostheses were investigated undecalcified by the Donath sawing and grinding technique. Prostheses in a nearly bland surrounding show a partial invagination in fibrous connective tissue without severe reaction of the prosthesis itself, whereas in prostheses removed from the neighbourhood of inflammatory processes or recurrent cholesteatoma a partial resorption of dentine with subsequent new bone formation could be observed. Due to the trouble-free clinical and histological performance in the human middle ear, the Dentine Ossicular Prosthesis can be well recommended as an alternative material in ossiculoplasty.

Adolescent↗

PubMed1992

[Intramuscular hemangioma of the posterior wall of the pharynx. Diagnosis and differential diagnosis].

We report on the case of a seven-year old boy who developed an enlarged swelling of the oropharynx. Clinical examination revealed a well demarcated cystic tumour. Histopathologically the diagnosis of an intramuscular haemangioma could be made because of the multitude of vascular spaces filled with erythrocytes lying between bundles of smooth muscles. Such a lesion coming from the posterior wall of the oropharynx is not described in literature. In differential diagnosis the angiosarcoma and the arteriovenous aneurysm must have been involved since there were multiple arteries and veins lying close together in couples. Moreover the adenotomia carried out one and a half year earlier prompted us to think about the possibility of a traumatic arteriovenous fistula.

Arteries↗

PubMed1992

Neurinoma of the facial nerve.

A case of facial neurinoma is reported. There was a progredient facial palsy persisting for one year. While X-ray examination as well as CT and MR did not show a pathological finding, classical topodiagnosis resulted in mastoidectomy, during which a neurinoma of 0.5 x 0.8 cm could be removed. The defect was reconstructed by an auricular nerve graft, with satisfactory functional results.

Adult↗

PubMed1992

[Diagnosis and differential diagnosis of squamous epithelial metaplasia in the parotid gland].

The authors report a case of proliferating squamous epithelium in the necrotic edge of multifocal oncocytic adenomatous hyperplasia of the parotid gland. A correct histological diagnosis is of great clinical relevance and difficulty, since similar findings can occur in mucoepidermoid carcinoma. The various cell types in the parotid gland and their roles in neoplasia are discussed.

Adenoma↗

PubMed1992

[Follow-up of sound pressure level at the tympanic membrane at varying impedance of the tympanic membrane-ossicular system].

We investigated the influence of varying compliance of the tympanic membrane on the sound pressure level of the human ear canal using a model with adjustable compliance. Decrease of compliance augments the sound pressure close to the tympanic membrane due to the increase of reflected sound pressure. This augmentation occurs in a narrow frequency area near the maximum resonance frequency and reaches 6 dB (SPL). These experimental data correlate well with clinical investigations in patients with middle ear effusion before and after operation and in patients performing the Valsalva manoeuvre.

Acoustic Impedance Tests↗

PubMed1991

[Tensile strength of the stapes footplate. Pressure-induced inner ear damage in operated ears caused by TORP prostheses?].

In a recent textbook concerning ear surgery, it is recommended to put some connective tissue on the stapes footplate before introducing a TORP. This should avoid penetration of the shaft of the TORP into the inner ear. Experimental studies were performed to estimate the pressure needed for pushing a TORP through the footplate. We found those pressures to be much higher than those which might occur by increasing pressure in the external ear canal or decreasing pressure in the middle ear. This means that perforations of the footplate are not due to one big event of changing pressure, but rather by chronic irritations or foreign body reactions. Anyhow, we consider the protection of the footplate by a layer of connective tissue to be very useful.

Ear, Middle↗

PubMed1991

[Bifenestration--a hearing-improving operation in severe ear malformations].

Bifenestration as an operation for hearing improvement is described in a case of congenital absence of the oval and round window. Besides the classical fenestration of the horizontal semicircular duct, an artificial round window was performed in the middle ear. Due to the acoustic resonance of the mastoid cavity, the resulting conductive loss in the higher frequencies was only 20-30 dB.

Adult↗

PubMed1990

[Air temperature in the outer ear canal--experimental studies in relation to radical cavity surgery].

By means of special probes, air temperatures were determined in external auditory meatus and in "radical" mastoid cavities. Under normal conditions, there was no difference between the two groups, the temperature next to the drum head being in the same range as the body temperature. Exposure to simulated wind only lowered the temperature significantly in cases with very wide external meatus; e.g., after surgery. Suction--as is used in the daily practice of cleaning ears in the ENT surgery--caused a very abrupt decrease in temperature. In cases with open mastoid cavities, there was vertigo with nystagmus, due to the caloric vestibular stimulus. -Operative techniques such as the obliteration of such cavities or the reconstruction of the posterior wall of the meatus can considerably reduce this phenomenon.

Air Movements↗

PubMed1990

[Electron microscopy studies of the collagen fiber structure of the human tympanic membrane in an adhesive process].

In an EM study, the collagen fiber arrangement of the lamina propria in adhesive otitis media was investigated. Nine biopsies of the tympanic membrane were taken intraoperatively, and compared with two normal ones. The physiological specimens showed a regular arrangement of collagen fibrils and fibers, the typical network of the lamina propria. This confirmed results reported previously. In all adhesive otitis media samples the regular structure of the fiber arrangement was disturbed. Degenerative processes were to be found in the form of hyaline changes, with the network character of the fibers no longer in evidence. In one specimen a mass of microfibrils was observed, which was possibly a sign of reparative processes. The pathohistological findings in adhesive otitis media may be due to mechanical stresses (tubal function). Aside from that, they may also be caused by the biochemical influence of specific collagenases, which have been found by several authors in secretory otitis was well as in cholesteatoma.

Biopsy↗

PubMed1990

[Epithelial migration following surgical obliteration of radical cavities].

We investigated whether the self-cleansing mechanism of the normal ear can be restored in operatively reconstructed open cavities. Dots of Indian ink placed on the drumhead were followed for up to 10 weeks. The epithelium migrates outwards, acting as a self-cleansing mechanism. Partial obliteration of open cavities is recommended in the light of other factors (acoustic phenomena, temperature protection of the inner ear).

Carbon↗

PubMed1990

A technique for the reconstruction of the posterior canal wall and mastoid obliteration in radical cavity surgery.

The open technique in cholesteatoma surgery has, besides a higher security concerning the recurrence of disease, some disadvantages: lifelong care for the cavity, often discharging granulations, and vestibular vertigo due to the lack of labyrinthine protection. Most of the disadvantages can be avoided by the obliteration of the mastoid cavity, for which many different techniques have been described in literature. The authors recommend a new method: the reconstruction of the posterior canal wall using autograft conchal cartilage and the obliteration of the mastoid cavity with hydroxyapatite granulate. The technique can be used for the treatment of old cavities as well as for one-stage surgery. The results of 25 cases are reported. Due to the elevation of the tympanic membrane on a nearly physiologic level and suitable tympanoplastic procedures an air-bone gap of less than 30 dB can be reached in more than 70%.

Adolescent↗

PubMed1990

[Elongated styloid process as a cause of dysphagia].

An elongated styloid process or a calcified stylohyoid ligament may cause dysphagia or craniofacial and cervical pain. Palpation and radiography confirm the diagnosis provided that it is considered. The only effective treatment is surgery. Eleven patients undergoing surgery for elongated styloids or calcified ligaments are reported. In all cases the symptoms disappeared or were relieved. An evaluation of the external versus the transoral approach is presented. The authors recommend the external one, as it provides adequate anatomical exposure of the styloid process and its relationship to the structures of the parapharyngeal space.

Adult↗

PubMed1989

[High-frequency jet ventilation in emergency tracheal puncture].

A case of obstruction of the upper respiratory tract is reported, in which an intubation or insufflation by rigid tracheobronchoscopes was not possible. Due to the anatomical situation after multiple operations and irradiation, coniotomy could not be performed. Blind puncture of the trachea with subsequent High Frequency Jet Ventilation has proved successful as an emergency approach to maintain respiratory function.

Airway Obstruction↗