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G Schade

Publications and source records attributed to G Schade.

At least 37 records · Page 2Linked to original sources
PubMed2002

[Physical and technical elements of short-interval, color-filtered double strobe flash-stroboscopy].

INTRODUCTION: Quantitative measurement of vocal fold movements can be done either with high-speed imaging or with short interval, color-filtered double strobe flash-stroboscopy. The physical and technical elements of this new technique are described. METHODS: Two special strobe units (KAY Elemetrics RLS 9100) are used in a master-slave configuration. In this way an adjustable interval of 0.1-2.0 ms between flashes is introduced. The strobe flashes are color filtered and are separated by a brief interval. By this means a double exposure is created in each video frame.Real-time visualization of opening and closing velocities over the entire length of the vocal fold from anterior to posterior is possible. Quantification is possible off-line after image calibration. CONCLUSION: Short-interval, color-filtered double-strobe flash stroboscopy allows quantitative measurement of the velocity of vocal fold movements during vibration at different pitches and sound pressure levels (SPL). Images gained with this new technique provide information about a dynamic property (velocity) of the vocal fold within a single image.Therefore, its use could be helpful from the aspect of clinical documentation.

Artifacts↗
PubMed2002

[Use of Ensemble tissue harmonic imaging to improve the resolution in ultrasound investigations of the head and neck area].

BACKGROUND: Using ultrasound diagnostic, deeper areas of tissue cannot be examined as easily as superficial areas. Therefore it was necessary to develop a new image processing technique for ultrasound platforms to improve the quality of sonographical resolution in deeper areas. Tissue Harmonic Imaging is a modern technique that uses the non-linear, "harmonic" parts of ultrasound waves. Ensemble Tissue Harmonic Imaging is a new technique that uses a "Wide Band Harmonic Imaging", based on a patented phase-inversion-technique, and improves imaging quality. AIM: Aim of the study is to show if Ensemble Harmonic Imaging can improve imaging quality even in superficial areas of tissue in comparison to fundamental B-Mode-technique. METHODS: A Sonoline Elegra(R) high-end-scanner with 7.5 MHz linear array was used for this study. Differences of techniques ("fundamental"-sonographic-mode versus Ensemble Tissue Harmonic Imaging(R)-mode) are shown by investigation of six patients with various lesions of the head and neck area. CONCLUSION: In all cases there was a gain of resolution by using Ensemble Tissue Harmonic Imaging even in superficial areas. Ensemble Tissue Harmonic Imaging improves the sonographical resolution and reduces the artifacts.

Artifacts↗
PubMed2002

[First impressions of the use of "SonoCT trade mark real-time compound imaging" in the head and neck area].

BACKGROUND: Diagnostic importance of sonography has improved significantly in the last ten years. Nowadays, sonography is the most common form of imaging technologies in medicine. Innovations like "Tissue Harmonic Imaging" provides higher contrast in deeper tissue layers. By use of sonographical panorama imaging techniques the documentation of topodiagnostic could be improved. Even three-dimensional-sonography has been possible for some years. With the development of "SonoCT trade mark Real-time Compound Imaging", a new technique has been developed to acquire more tissue information for clinicians. Multiple coplanar, tomographic images from different viewing angels are obtained. In real-time frame rates this results in an single compound image. METHODS: In this study, seven patients with tumors or other pathologies of the head and neck region were examined using the fundamental mode versus the "SonoCT trade mark Real-time Compound Imaging" mode. Image resolution and subjective quality of these sonographic images were compared. RESULTS: In all cases the results were improved by use of the "SonoCT trade mark Real-time Compound Imaging" mode. The contrast was better and the image resolution was higher compared to "fundamental" mode. CONCLUSIONS: "SonoCT trade mark Real-time Compound Imaging" has been developed to acquire and to process ultrasound images in a new and different way. This new method provides increased image contrast, a reduction of inherent artifacts of conventional ultrasound and overall gain of quality within sonographical imaging.

Carotid Stenosis↗
PubMed2001

[Experiences with using the ultrasound contrast medium levovist in differentiation of cervical lymphomas with color-coded duplex ultrasound].

AIM: Proof of intranodal vessels in lymph nodes of the head and neck region and their association to specific types of vascularisation enables categorization of lymph nodes and improves preoperative predictability of tissue dignity. In many lymph nodes imaged by colour duplex sonography no intranodal vascularisation can be found. The purpose of the study was to find out if sonographic categorisation of lymph nodes, which do not show intranodal vessels in normal colour duplex sonography, is enabled with the contrast amplifier Levovist. METHOD: In 30 patients with metastasis in lymph nodes, malignant lymphomas or inflammatory lymph nodes with no or poor intranodal vascularisation, we administered Levovist, a contrast amplifier given intravenously, during colour duplex sonography. RESULTS: Intranodal vascularisation could be visualized in all cases by the use of Levovist contrast amplifier during the sonographic investigation. CONCLUSION: Use of the contrast amplifier Levovist leads to an improvement of the categorisation of lymph nodes. Especially inflammatory lymph nodes show more intranodal vessels in the hilus area, whereas metastatic lymph node vessels show no link to the hilus area. Preoperative diagnostic procedures may take advantage of this new technique.

Contrast Media↗
PubMed2001

[Topographic diagnosis in the area of the head-neck: initial experiences comparing ultrasound panorama images with CT and MRI].

PURPOSE: Due to the restricted width of the ultrasound array, documentation of topographical correlations in B-scan-echography is still difficult. By means of Color SieScape it is possible to produce successive images of the regions of interest by lateral movement of the ultrasound array. Aim of the present study was to evaluate this new method in comparison to CT and MRI. METHOD: 18 patients with tumors in different areas of the head and neck region were examined by CT or MRI and by sonography. Color SieScape was used for documentation. A Sonoline Elegra ultrasound platform with 7.5 MHz linear array was used for the investigations. RESULTS: Because of claustrophoby no MRI-investigation could be done in 4 of the patients. Sonography and Color SieScape documentation was possible in all cases. In addition to the panorama-information of SieScape technique in every investigation by Color SieScape large and very small vessels could be documented in colour. CONCLUSION: By the use of Color SieScape the identification of the topographical correlations is improved. The spatial resolution is comparable to MRI and better than in CT. Investigation of patients who suffer from claustrophobia is much easier by Color SieScape. The imaging of parapharyngical structures could not be improved by Color SieScape. Nevertheless it is the only technique for the coloured documentation of even small vessels and topographic relations. Color SieScape investigations are faster and less expensive than CT or MRI.

Humans↗
PubMed2000

Plasmacytoma of the tonsil with AL amyloidosis: evidence of post-fibrillogenic proteolysis of the fibril protein.

We report of a 58-year-old Caucasian man who was referred to the University Hospital with a greatly enlarged left tonsil which showed calcifications on computed-tomography scans. Histopathology revealed a plasmacytoma with secondary AL amyloidosis, ossifications, and multinucleated foreign-body-type giant cells. N-terminal sequencing of amyloid-fibril proteins purified from the formalin-fixed tissue showed the presence of two proteins of different size; these were of lambda-light-chain origin (subgroup V), measured approximately 15.2 kDa and 10.5 kDa, and had identical N-terminal ends (YVLTQPP). When the amyloid deposits were immunolabeled with a polyclonal antibody directed against lambda light chain, they showed two staining patterns: some deposits showed intense immunolabeling while others were not immunoreactive. Immunostaining of amyloid was completely absent after protease pre-treatment. Immunoelectron microscopy with gold-labeled secondary antibodies showed staining that was spatially related to amyloid fibrils and suggested that the antibody probably detected the fibril protein. Therefore, our hypothesis in this case is that the different immunostaining patterns are due to a post-fibrillogenic proteolysis of the fibril protein at the C-terminal end of the light chain, as indicated by the presence of two differently sized lambda-light-chain fragments with identical N-terminal ends.

Amyloidosis↗
PubMed1998

Organochlorine pesticides and polychlorinated biphenyls in human milk of mothers living in northern Germany: current extent of contamination, time trend from 1986 to 1997 and factors that influence the levels of contamination.

This study reports the concentration levels of PCB, DDT, HCB and beta-HCH in the human milk of women living in northern Germany over a period of 12 years and determines factors that may influence these levels. From 1986 to 1997 more than 3500 milk samples were analyzed for organochlorine compounds. A questionnaire was used to obtain information regarding personal characteristics, life style factors and eating habits. Descriptive statistics of concentration levels were computed to characterize the current extent of contamination. To follow time trends across the years homogeneous subgroups were compared and multiple regression analyses were used to investigate associations between determining factors and specific contaminants. Between summer 1995 and summer 1997 the median PCB concentration level was 0.502 mg/kg, the median DDT level 0.202 mg/kg, the median HCB level 0.065 mg/kg and the median beta-HCH level 0.036 mg/kg, all values expressed on a fat basis. The median concentration levels decreased by 80-90% during the past 12 years and the median PCB levels by 60%. The concentration levels of all substances were positively correlated with maternal age and negatively associated to parity, to the total period of breast-feeding and to a weight increase of mothers before and after delivery. Post-pregnancy BMI was a significant predictor of the likelihood of having higher concentrations for DDT, HCB and beta-HCH and of having lower concentrations for PCB levels. A balanced diet for at least 3 years was related to lower HCB and beta-HCH levels. Women who ate more than 100 g of fish or more than 700 g of meat per week were more likely to have higher PCB and beta-HCH levels or higher HCB levels, respectively. Higher HCB and beta-HCH concentration levels were associated with lower birth weights of female infants.

Adult↗
PubMed1998

[Value of duplex ultrasound in diagnosis of parotid tumors].

BACKGROUND: The sensitivity of diagnostic imaging of processes in the parotid gland has been increased by improved spatial resolution, yet specificity remains unchanged. The purpose of this study was to determine whether the low-flow color duplex technique alters the specificity of B-mode ultrasonography. PATIENTS AND METHODS: Forty-one patients with tumors of the parotid gland were examined by color duplex echography as well as histologically. Twenty-eight of the 41 patients had benign tumors and 13 had malignant disease. In 17 of 41 patients, color duplex ultrasonography failed to detect any vascularization within the tumor. Histopathological examination showed that 3 of these 17 tumors were malignant and 14 of 17 were benign. Intranodal vascularization was detected in 24 cases. Ten of these patients were found to have malignant tumors of the parotid gland; 14 had benign parotid tumors. RESULTS: Our present findings show that marked intratumoral vascularization especially appears in malignant tumors. In contrast to lymph nodes, the location and texture of intranodal blood vessels do not provide information about the nature of the neoplasm. CONCLUSIONS: Low flow duplex ultrasonography does not increase the specificity of preoperative examination in tumors of the parotid gland.

Diagnosis, Differential↗
PubMed1996

Quality of documentation in medical reports of diabetic patients.

In a retrospective analysis of 752 consecutive medical reports of patients with insulin- or non-insulin-dependent diabetes mellitus, we investigated the completeness of documentation of indicators of quality of care. The medical reports are the currently used form of documentation which is sent to the General Practitioner after the patient's discharge from hospital. The indicators of care were data on clinical history, physical examination, laboratory results and secondary complications. The documentation was incomplete; e.g. in 8.0% of insulin-dependent (IDDM) and in 26.4% of non-insulin-dependent diabetics (NIDDM), HbA1c was missing. In 7.6%, the type of diabetes was not stated. The frequency of recorded secondary complications was lower than it has to be expected considering metabolic control and duration of diabetes of the studied group. Documentation was more complete for IDDM patients. The reports of NIDDM patients with incipient or overt diabetic nephropathy revealed less frequent recordings of data on lipid metabolism and blood pressure compared to the group without nephropathy. The documentation of indicators of quality of care in medical reports for general practitioners is incomplete for many diabetic inpatients. Standardized methods of documentation are required urgently.

Adolescent↗
PubMed1990

[Magnetic resonance tomography of scaphoid pseudarthrosis: clinical and x-ray aspects].

37 patients with non-unions of fractures of the carpal scaphoid were examined with MRI and the results compared with conventional radiographs. Advantages of MRI are the documentation of concomitant soft tissue changes in the region of the pseudarthrosis, and the early detection of osteonecrosis of one of the fragments. Advantages of conventional radiographs are the exact documentation of cancellous bone morphology and the position of the fragments.

Adolescent↗