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T Vogl

Publications and source records attributed to T Vogl.

At least 145 records · Page 8Linked to original sources
PubMed1990

[The value of 3D proton spin tomography reconstruction as exemplified by an extensive parotid adenoma].

In the past few years, 3 D reconstruction has been established as a new imaging method in various medical fields, such as orthopedic surgery and neurosurgery. In a former article, the authors introduced a new 3 D imaging method for the head and neck. The present study reports the case of a 37-year-old woman with a huge adenoma of the parotid gland. The tumor grew along the skull base, protruding onto the left tonsil. The diagnostic value of the authors' reconstruction method for lesions in the head and neck is discussed. The results indicate that this technique might be of significant clinical importance for special questions arising in the head and neck region as well as for preoperative planning in the case of certain tumors.

Adenoma↗
PubMed1990

[Temporary threshold shift after nuclear magnetic resonance tomography].

The third-octave band levels of the noises produced in a MR-imager (1.0 Tesla Magneton, Siemens) were measured. Corresponding sounds presented through earphones have been used in simulation experiments to produce in normal-hearing listeners a temporary threshold shift lasting several minutes. These effects could be verified objectively using otoacoustic emissions. The consequences especially for patients with already impaired hearing are discussed: ear protection is strongly recommended.

Auditory Fatigue↗
PubMed1990

[Modern imaging of the larynx].

Many diseases of the larynx can be diagnosed by clinical examination. In many cases, however, further diagnostic procedures are necessary to receive adequate information on the localisation and extent of the lesion. In the present paper the authors report on the different possibilities of diagnostic imaging of the larynx. The value of each technique is discussed to set adequate indications as well as to recommend an appropriate imaging for laryngeal lesions.

Contrast Media↗
PubMed1990

[The further development of the 3D-MRI reconstruction technic for the head-neck area].

Twenty-one healthy volunteers and seventeen patients with head and neck lesions were examined with 3D MR imaging since the end of 1988. A new kind of reconstruction mode was used, which shows the structures of the region of interest by overlaying a predetermined window within the three-dimensional reconstruction of the head. Using this mode, the morphology of the lesion could be evaluated more precisely than by using individual two-dimensional slices. With regard to preoperative surgery planning, the previous results were insufficient. With the new development and increased capacity of the MRI-technique and improvement of the reconstruction mode it is now possible to "cut" several slices in different orientations into the head achieving higher resolution of the images. The innovation of the method and its actual clinical value is discussed in the example of a meningioma of the sphenoid which has been examined by both reconstruction modes.

Head↗
PubMed1990

[Tracheal compression by the brachiocephalic trunk in infants--surgical treatment of 30 cases].

This is a report on 30 cases of innominate artery compression of the trachea and its operative correction by an aorto-truncopexy. Tracheoscopy is the most important examination for arriving at the diagnosis. Magnetic resonance imaging (MRI), which offers representative pictures of many moments of expiration and inspiration, shows the anatomic relationship between the innominate artery, the aortic arch and the trachea, also demonstrating the extent of the tracheal compression. Surgical treatment is indicated if narrowing of the lumen of the trachea is greater than 70%. By fixing the aortic arch and the proximal innominate artery at the back of the sternum the trachea is relieved of its compression. In 30 children there was no unsuccessful operation, and none of them died.

Aorta, Thoracic↗
PubMed1990

[3D-MRT-reconstructions of space-occupying lesions in the head and neck regions].

3-D reconstructions in the head and neck were carried out on 21 normals and 11 patients with space-occupying lesions, both before and after the administration of Gd-DTPA. The 3-D reconstructions were obtained by the "ray-tracing" method. For the 3-D reconstructions, portions of the skull surface image were removed to permit views of the deeper tissues. The 3-D reconstructions included an hypoglossus neurinoma, a glomus tumour, two carcinomas of the maxillary antra, three naso-pharyngeal carcinomas, a parotid adenoma, an oro-pharyngeal haemangioma and two lesions in the neck. The 3-D reconstructions provided a better understanding of the morphology than was obtained from the two-dimensional images. 3-D reconstructions of lesions in the head and neck will become a valuable diagnostic method for demonstrating space-occupying lesions, particularly with regard to surgical planning.

Adenoma↗
PubMed1990

[MRT of tumors of the larynx and hypopharynx using Gd-DTPA: clinical value].

Thirty one patients with tumours of the larynx and hypo-pharynx were studied by MRI, both with and without the para-magnetic contrast medium, GD-DTPA. The results were compared with pre-operative laryngoscopy and the final pathological tumour classification. The most accurate results were obtained by comparing T1-weighted sequences before and after the use of GD-DTPA. Because of the relatively rapid mode of examination and the specific enhancement, the method proved ideal for evaluating tumours of the larynx and hypo-pharynx. MRI is a valuable diagnostic technique for staging and treatment planning of patient with tumours of the larynx and hypo-pharynx.

Contrast Media↗
PubMed1990

Tumors of the nasopharynx and adjacent areas: MR imaging with Gd-DTPA.

The purpose of this study was to describe our experience with Gd-DTPA-enhanced MR imaging in the evaluation of the most common nasopharyngeal tumors. Forty-two patients with tumors of the nasopharynx and adjacent spaces had MR imaging before and after IV injection of Gd-DTPA. Images were obtained with a 1.0-T superconducting magnet imaging system in transverse, coronal, and sagittal planes with T1- and T2-weighted sequences. MR images were compared with CT scans and tumor histology. The studies were categorized by using a grading system with grades ranging from unsatisfactory (grade 0) to optimal (grade 3). Contrast-enhanced MR enables better identification of small anatomic details such as both palatini muscles and the pharyngobasilar fascia. MR after Gd-DTPA was superior to CT in all cases except for tumors of the maxillary sinuses. MR with Gd-DTPA is recommended for tumors that are small and difficult to detect on the initial nonenhanced MR examination or that show subtle infiltrations. Because of the increased cost and longer examination time, MR with Gd-DTPA does not need to be done when large tumors are well delineated.

Carcinoma, Adenoid Cystic↗
PubMed1990

[Magnetic resonance tomography as a new diagnostic criterium in vascular-induced stenoses of the upper airways in childhood].

Magnetic resonance (MR) imaging of the trachea was performed in twenty-one children with congenital or acquired narrowing of the trachea or main bronchi. The demonstration of the trachea and the surrounding tissue and vessels on MR images permitted the evaluation of the cause of trachea, compression and the degree and location of collapse. MRI is a well-suited modality for characterizing tracheal narrowing without employing ionizing irradiation or intravenous contrast medium. In the cases presented MRI should be the diagnostic step of choice after tracheo-bronchoscopy. It is an enrichment of the diagnostic possibilities for extrinsic tracheal or bronchial stenosis in pediatric patients.

Airway Obstruction↗
PubMed1990

Chromosome aberrations in peripheral lymphocytes of patients irradiated with 15-MeV-photons for Morbus Hodgkin.

Chromosome aberrations in peripheral lymphocytes of two Morbus Hodgkin patients were analyzed before and during the ongoing radiotherapy. Venous blood was taken 5 min after and before a successive irradiation in order to examine the dose dependence as well as the influence of mixed unirradiated and irradiated lymphocytes on the aberration rate. Both patients showed an overdispersed distribution of dicentric chromosomes and acentric fragment from the outset of therapy and independent of the time blood was taken. The dose-effect relationship established for both types of aberrations by the Maximum-Likelihood approach may best be described as being linear. The dose effect curves 5 min after a fraction did not differ from those calculated for a time thereafter. However, after the first two irradiations, the rate of dicentric chromosomes in the blood samples taken at a later time was about twice as high as that in the samples taken 5 min after irradiation. Dicentric chromosomes were twice more frequent during the entire radiotherapy than acentric fragments and about 30 times more frequent than centric ring chromosomes.

Adult↗
PubMed1989

[The value of high-resolution computerized tomography in abnormalities of the middle ear].

Middle ear malformations are common congenital disorders of the head and neck area. Recent advances in plastic and middle ear surgery have improved the prognosis of patients suffering from congenital hearing disorders. However, sophisticated preoperative procedures are mandatory. The development of HR-CT has improved the radiologic possibilities to evaluate middle ear disorders significantly. In the present study we examined by means of HR-CT twenty patients with congenital middle ear malformation. Our findings include different sizes of the middle ear as well as dysplastic alterations of the malleus and incus. The inner ear was normal in almost all cases. Our results indicate that preoperative HR-CT is a reliable diagnostic method to demonstrate middle ear disorders.

Ear Ossicles↗
PubMed1989

[Multiplanar imaging of the temporal bone. Initial results].

In the head and neck area CT imaging (particularly the HR-technique) is a well-established diagnostic procedure. Besides other locations it has been successfully used in the preoperative evaluation of the temporal bone. Nevertheless, the sophisticated anatomy of this special area is hard to interpret in certain cases. In the present study we report on our preliminary results in producing a multiplanar reconstruction of the area mentioned above. Temporal bones were used that had been excised during autopsy. The specimen were examined under a CT imager of the 3rd generation with a high-resolution mode. Sections of 1 mm thickness were obtained. For the evaluation a surface model was used; the segmentation was carried out mainly automatically. The surface was calculated using a triangulation algorithm. The obtained data enabled us to receive three-dimensional aspects of the temporal bone; these reconstructions could be examined from any desired perspective. Our results indicate that the multiplanar reconstruction might be of great importance for the diagnostic evaluation of temporal bone diseases in the future. In the meantime several technical problems have to be solved to guarantee a sufficient quality of the reconstructed specimen.

Computer Simulation↗
PubMed1989

[Radiologic diagnosis of the middle ear. Possibilities and perspectives].

During the past few years the importance of imaging methods for the diagnosis of head and neck diseases has increased significantly. Due to the rapid development of new techniques like "high-resolution" CT (HR-CT) and magnetic resonance imaging, radiology has become an important factor in the preoperative evaluation of many diseases in our discipline. The middle ear region in particular is known to be a complicated area and was often hard to interpret by radiological methods used so far. In the present paper the diagnostic value of HR-CT is demonstrated. Over the past two years we examined 130 patients suffering from middle ear diseases like malformations (MEM), otosclerosis, cholesteatoma and temporal bone fractures (TBF) with HR-CT. From our point of view the indications for this special examinations should be limited to MEM and TBF. The results and side effects of HR-CT and conventional tomography are compared and discussed. Finally, future perspectives of middle ear imaging are presented. Different reconstructive techniques have been developed during the past years, which might supply additional information for further questions arising in middle ear pathology in the future. At the present time none of these methods are ready for routine clinical use.

Ear Diseases↗
PubMed1989

[Modern radiologic diagnosis of the nasopharynx].

The nasopharynx is one of the most delicate areas of the head and neck for diagnosis and treatment. Biopsies can be taken easily under local anaesthesia; however, since many tumours in this particular region grow in the submucosa, biopsies taken from the superficial tissue layers might not show any signs of malignancy. Thus, diagnostic imaging has become important in evaluating the nasopharyngeal region. Until the early seventies, when computed tomography (CT) was introduced, conventional tomography was commonly used. Since the development of CT and --particularly--the "high-resolution" technique, tumour infiltration of the skull base and parapharyngeal space as well as intracranial extension can be evaluated sufficiently and the different compartments of the soft tissue can be clearly distinguished due to their varying density. Magnetic resonance imaging (MRI)--a new technique introduced a few years ago--yields a much better soft tissue contrast than CT. Contrast enhancement after application of Gd-DTPA provides further information on tumour outlines and architecture. Benign lesions can be distinguished from malignant tumours, as well as recurrent tumours from postoperative fibrosis. MRI can also show large bony defects while minor infiltrations of the skull base are detected by HR-CT. Both MRI and CT are well-established methods in diagnosing diseases of the nasopharynx and its surroundings. For evaluations of the vascular supply prior to operation digital subtraction angiography (DSA) might be necessary in some cases.

Contrast Media↗
PubMed1989

[Infratemporal gout tophus--a rare differential diagnosis in primary parotid gland disease].

Soft-tissue tophi can be observed in up to 50% of patients with primary gout. They are firm deposits of monosodium urate in crystal form, which develop from pinhead-size to egg-size in the subcutaneous tissue. In the field of ear, nose, and throat diseases tophi have been described in such rare locations as the wing of the nose, the tongue, the epiglottis, and the arytenoid and thyroid cartilage. Tophus formation at the temporomandibular joint with extension into the fossa infratemporalis has been mentioned only three times in the world literature. -In the present paper, the authors report on the extraordinary location of an urate tophus in the fossa infratemporalis - in this case, there was even destruction of the middle base of the skull - which had been misinterpreted for years, having been diagnosed as a primary disease of the parotid gland.

Aged↗
PubMed1989

[In vivo 31P magnetic resonance spectroscopy and MRI in patients with superficial tumors].

Simultaneous 31P-MR spectroscopy (MRS) and MR imaging (MRI) of 10 patients suffering from superficial tumours like carcinoma, lymphoma and adenoma, revealed significantly enhanced concentrations of phosphomonoester, phosphodiester and inorganic phosphorus in the tumour, whereas the concentration of phosphocreatine was lower in comparison to muscle tissue. In all tumours the pH showed a slight alkaline shift. The existing of necrotic regions detected by MRI was accompanied by an increase of inorganic phosphorus in the spectra. A follow-up study of a patient with a lymphoma during chemotherapy showed a tumour regression, whereas the spectra indicated a continuous approach of tumour values to the muscle values.

Contrast Media↗