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K Wernecke

Publications and source records attributed to K Wernecke.

At least 19 recordsLinked to original sources
PubMed2007

[Results after lidloading with rigid gold weights--a meta-analysis].

INTRODUCTION: For the surgical therapy of lagophthalmos rigid gold implants were used. There are a lot of studies using rigid gold implants with widely different complications. In the primary study the small amount of patients is often a problem. The aim of our study was to survey the postoperative results and complications after insertion of rigid gold implants and to statistically compare the results with a meta-analysis. MATERIAL AND METHODS: 38 publications on 1000 rigid gold implants were analyzed in the context of a meta-analysis of the postoperative results. RESULTS: Complete lid closure can be obtained in 84.5 % with the rigid gold implants. The postoperative complication rates were 13.4 % for bulging, 6.4 % for migration, 6.8 % for extrusion, 11.5 % for corneal astigmatism and 7.0 % postoperative infections. DISCUSSION: Lidloading is a very simple and reversible procedure for the surgical treatment of lagophthalmos. The statistical analysis in using rigid gold implants showed a significant rate of postoperative complications. To increase the effectivity of the treatment method these results should be taken into account for alternative implants.

Eyelid Diseases↗
PubMed2006

[Measurement of skull thickness by ultrasound].

BACKGROUND: The presurgical diagnostic for measurement of skull thickness for implantations of epithesis or bone anchored hearing aids is limited on computed tomography (CT) of petrosal bone up to now. Testing of ultrasound for measurement of skull thickness is the aim of our study . MATERIAL AND METHODS: 20 patients has been included, which had got a computed tomography of nasal sinus, skull or petrosal bone. The potential localisations of implantations have been measured by 3D-reconstruction of computed tomography. The results have been statistical compared by sonographic investigations (7.5 MHz Soundhead) at the same localisation. RESULTS: The mean skull thickness has been 5,2 mm in computed tomography. Comparison has described a mean skull thickness of 4,2 mm in sonography. Statistical comparison has shown that ultrasound has been measured statistical significant too small. CONCLUSIONS: The skull thickness can be described and measured by sonography. However mean skull thickness has been measured statistical significant too small. In spite of this, conclusions relating to presurgical diagnostic, for instance for the implantation of epithesis and bone anchored hearing aids, can be drawn by sonographic data.

Cochlear Implantation↗
PubMed2006

[Ultrasound of the upper eyelid to evaluate tarsal curvature in facial palsy].

BACKGROUND: Treatment of paralytic lagophthalmos involves surgical repair, requiring exact knowledge of eyelid anatomy. While there are extensive studies on anatomical eyelid measurements in healthy eyes, no data exist on the changes in the functional anatomy of the upper eyelid in paralytic lagophthalmos. The aim of this study, was to examine by ultrasound the upper lid tarsus during changes in the patient's line of vision, and to answer the question of whether there are changes in the curvature radius of the tarsus, caused by facial paralysis with resultant lagophthalmos. MATERIAL AND METHODS: Two groups were formed. The first group consisted of 50 subjects with healthy eyes, and the second contained 47 patients with paralytic lagophthalmos. The upper lid tarsal radius, when looking straight ahead and in the abducted position, was determined by ultrasound with a 7.5 MHz scanner in the non-contact mode, and then compared statistically. RESULTS: Both groups showed a highly significant difference in the tarsus curvature, when looking straight ahead and in the abduction position. While there was no significant difference between both groups in the abduction position, they differed significantly when looking straight ahead. Also, a significant difference was noted, between the eyes of healthy subjects and the healthy eye in patients with facial palsy. CONCLUSION: The changes in curvature of the tarsal plate, when looking straight ahead, can be explained by the loss of tone in the paralyzed Orbicularis Occuli muscle. This means, that in addition to the lagophthalmos resulting from facial paralysis, changes occur in the functional anatomy of the upper eyelid, which must be considered during surgical correction. Additionally, the physiological loss of tone of the upper eyelid tarsal plate, which comes with age, has a certain influence.

Eyelid Diseases↗
PubMed2005

[Implantation of lid weights for therapy of lagophthalmos].

BACKGROUND: The aim of this study was to compare the clinical outcome and complication rate of rigid gold implants and flexible platinum chains in 96 patients treated for lagophthalmos. PATIENTS AND METHODS: We treated 50 patients with peripheral facial palsy and lagophthalmos using rigid gold implants and 46 using a flexible platinum chain. Besides subjective assessment by the patients, reduction of lagophthalmos, improvement of visual acuity, and pre- and postoperative grade of keratopathy were evaluated. RESULTS: Both groups showed a statistically significant reduction of lagophthalmos and keratopathy and increase of visual acuity. Postoperative complications were observed in both groups. Two extrusions occurred in the group receiving gold implants. The incidence of corneal astigmatism and bulging of the implant was statistically significantly lower in the platinum chain group. CONCLUSIONS: The use of flexible platinum chains instead of rigid gold implants for therapy of lagophthalmos leads to a reduction of the complication rate, thus improving the clinical outcome.

Equipment Failure Analysis↗
PubMed2005

[Lidloading and intraocular pressure].

BACKGROUND: Implantation of rigid gold or platinum lid weights (lidloading) represents the most common method for therapy of patients with lagophthalmus as a result of facial palsy. In a more recent approach also flexible platinum chains have been used. Glaucoma has frequently been described as a contraindication for lidloading. The aim of this study was to proof if lid weights lead to an increase of the intraocular pressure (IOP). PATIENTS AND METHODS: In a prospective study the IOP has been measured before and after implantation of 46 rigid gold implants and 39 flexible platinum chains in patients with paralytic lagophthalmos. RESULTS: Neither the implantation of rigid gold implants nor the use of the flexible platinum chain lead to a statistically significant change of the IOP. There was also no difference between the two groups. CONCLUSION: With this study we could demonstrate that glaucoma is not an absolute contraindication for the use of lid weights in patients with paralytic lagophthalmos. Moreover a lid weight is easily removable if complications should occur.

Contraindications↗
PubMed2001

Serum levels of the angiogenic cytokines basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) in multiple myeloma.

Angiogenesis is a crucial process in growth and progression of cancer and there is growing evidence that neovascularisation is important in hematological malignancies. Since an increased angiogenic potential has been identified in multiple myeloma, we simultaneously measured circulating serum levels of the cytokines bFGF, VEGF, HGF and IL-6 by ELISA in 67 patients with multiple myeloma or monoclonal gammopathies of undetermined significance (MGUS) and in 20 controls. Median values of bFGF were 4.7 pg/ml in healthy volunteers, 6.2 in MGUS, 6.3 in myeloma stage I, 13.4 in stage II and 21.7 in stage III. Myeloma patients had significantly higher bFGF serum levels than controls (p<0.001). Pretreatment bFGF levels differed significantly in the Salmon and Durie stages I-III (p=0.02) and were significantly elevated in stage II-III compared to stage I myeloma (p=0.02). In patients responding to chemotherapy according to the CLMTF criteria, a significant decrease in serum bFGF, VEGF and HGF levels occurred (median pretreatment values for bFGF 23.9 pg/ml, post-treatment 6.5 pg/ml; p<0.001, for VEGF 223 pg/ml versus 105 pg/ml; p=0.02 and for HGF 1429 pg/ml versus 1077 pg/ml; p=0.02, respectively). In 11 patients who did not achieve a remission, there was no significant decrease in bFGF, VEGF and HGF levels. These data show that myeloma in stages II and III is associated with an increase in serum bFGF concentrations and give the first report that effective chemo-therapy is accompanied by a significant decrease in the angiogenic factors bFGF, VEGF and HGF, while no decrease of these factors could be found in nonresponders.

Adult↗
PubMed2000

Reduced procedural risk for coronary catheter interventions in carriers of the coagulation factor VII-Gln353 gene.

OBJECTIVES: We have focused on the role of coagulation factor VII (FVII) Arg353Gln polymorphism as a risk predictor of complications following percutaneous transluminal coronary angioplasty (PTCA), directional coronary atherectomy (DCA), and stenting. BACKGROUND: The FVII Arg353Gln mutation decreases FVII activity, and presence of the Gln353 allele could be protective against thrombus formation during catheter interventions. METHODS: A total of 666 consecutive patients with coronary artery disease who had undergone PTCA (n = 280), DCA (n = 104), or stenting (n = 282) were followed up for a 30-day composite end point, which included need for target vessel revascularization, myocardial infarction, and death. The Arg353Gln polymorphism of FVII was determined by PCR/RFLP assay. RESULTS: Carriers of the Gln353 allele had significantly lower levels of total FVII activity (FVIIc, -20.7%, p < 0.001) and of activated circulating FVII (FVIIa, -32.7%, p = 0.03) compared with Arg353/Arg353. The composite end point occurred in 43 patients: 4 were heterozygous Arg353/Gln353, and 39 were homozygous Arg353/Arg353. The incidence of the composite end point was 2.5% in carriers of the Gln353 allele and 7.7% in Arg353/Arg353 homozygotes (p = 0.013). This corresponds to a 72% risk reduction in carriers of the Gln353 allele (relative risk: 0.28; 95% confidence interval: 0.09-0.81; p = 0.02). CONCLUSIONS: The Gln353 allele of FVII is associated with substantial risk reduction in adverse events that complicate coronary catheter interventions. With the perspective of active site-blocked activated FVII (FVIIai) as conjunctive medication, the results suggest that the FVII genotype should be taken into due consideration in assessment of FVIIai medication and of its dosage.

Aged↗
PubMed2000

Ultrasound study of the pleura.

This review describes the sonographic morphology of the most important pleural diseases and defines the role of sonography compared with chest radiography and CT in diagnostic work-up of pleural pathology.

Artifacts↗
PubMed2000

Elevated serum leptin in patients with coronary artery disease: no association with the Trp64Arg polymorphism of the beta3-adrenergic receptor.

BACKGROUND: Serum leptin is associated with the occurrence of cardiovascular risk factors but it is unknown whether leptin is also associated with cardiovascular disease. Another open question is whether the Trp64Arg polymorphism of the beta3-adrenergic receptor (beta3-AR) is a determinant of circulating leptin. OBJECTIVES: We measured serum leptin concentrations in a large group of patients with angiographically assessed coronary artery disease (CAD) and investigated the relationship between the Trp64Arg polymorphism of the beta3-adrenergic receptor (AR) and serum leptin. PATIENTS AND METHODS: Leptin was measured in the fasting state in 1000 consecutive patients with angiographically confirmed CAD by radioimmunoassay. The codon 64 T/C polymorphism of the beta3-AR gene was analysed by the polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP) technique. Controls were 1000 age-, gender- and weight-matched subjects without clinical signs of CAD. RESULTS: Serum leptin concentrations were significantly higher in patients with CAD than in those without CAD (median: 6.8 vs 6.1 ng/ml, P < 0.001). In a multiple regression analysis leptin was found to be a determinant of CAD (P = 0.005) along with established risk factors. No differences in serum leptin were observed between wild-type and heterozygous carriers of the Trp64Arg mutation of the beta3-AR gene, whereas the small group of homozygous carriers had higher leptin due to their higher BMI. In a multiple linear regression analysis, body mass index, gender and fasting insulin were the main significant determinants of serum leptin, whereas the beta3-AR polymorphism had no effect. CONCLUSIONS: Patients with coronary artery disease exhibit higher serum leptin concentrations than age- and gender-matched controls of comparable BMI, indicating that leptin could contribute to the development of cardiovascular disease, possibly via activation of the sympathetic nervous system. The Trp64Arg variant of the beta3-adrenoceptor did not influence serum leptin.

Aged↗
PubMed1994

Sonographic features of mediastinal tumors.

Although mediastinal sonography, thus far, is used rarely in the United States, it might play a role in the diagnostic workup of mediastinal pathology as an adjunctive examination technique to other imaging studies (chest radiography, CT, and MR imaging). Mediastinal sonography is an effective and inexpensive imaging method, with a higher sensitivity than conventional radiographs, for the detection of mediastinal tumors [1-3]. The diagnostic advantage of mediastinal sonography over chest radiography results from its capability to demonstrate deep central mediastinal lymph nodes sonographically long before a displacement of pleuromediastinal lines occurs [3]. Mediastinal sonography is inferior only marginally to CT in the detection of supraaortic, pericardial, and prevascular lesions (sensitivity, 98-100%), but certain compartments (e.g., the posterior mediastinum and the paravertebral region) can be evaluated only with CT or MR imaging [3]. In addition to the assessment of size and topographic characteristics of mediastinal masses, sonography precisely visualizes the internal structure of the tumor, which may suggest a specific diagnosis when considered along with the clinical presentation and the location of the tumor [4]. This article illustrates the sonographic appearance of various mediastinal tumors.

Aortic Diseases↗
PubMed1994

[Transthoracic punch biopsy of mediastinal tumors].

48 consecutive patients underwent biopsy of anterior mediastinal tumors under sonographic guidance by the use of cutting needles up to 2.0 mm in diameter. The results of needle biopsies were compared with the final diagnoses, which was proved with pathologic studies or clinicoradiologic follow-up. In 39 (93%) of 42 malignant tumors malignancy could be readily diagnosed. Examinations of the microcylinders of tissue resulted in correct histologic diagnoses in 32 (76%) of 42 malignant tumors including 13 (81%) of 16 Hodgkin's lymphomas, 6 (66%) of 9 non-Hodgkin lymphomas, 2 (66%) of 3 thymomas and 9 (82%) of 11 carcinomas. All 6 benign lesions were correctly identified. No complications such as hemorrhage or pneumothorax were encountered.

Adolescent↗
PubMed1993

[Pancreatic metastases: sonographic and computed tomographic findings].

We analysed sonographic (n = 19) and CT (n = 15) findings in 19 patients with intrapancreatic metastases (solitary: n = 8, multiple: n = 11) from solid tumours. The diagnosis was confirmed either histologically (n = 5) or by the follow-up showing decrease of the size of the lesion due to chemotherapy (n = 3) or progression without specific therapy (n = 11). Clinically or serologically organ-related symptoms were found in 5 cases, whereas the rest of the patients were free of symptoms. Sonographically the metastases appeared hypoechogeneic compared to normal pancreatic parenchyma. In 15 cases CT at the time of sonographic investigation demonstrated hypodense intrapancreatic lesions (8/15) or bulging of the organ contour without differences in density (2/15). In some patients (5/15) sonographically detected metastases measuring less than 2 cm were not discovered via CT. In a patient with known malignancy multiple intrapancreatic lesions must be considered as metastases. Differential diagnosis includes diffusely growing pancreatic carcinoma, haemorrhagic necrotising pancreatitis and focal infiltrates due to malignant lymphoma.

Adult↗
PubMed1992

Comparison between high-field-strength MR imaging and CT for screening of hepatic metastases: a receiver operating characteristic analysis.

The diagnostic performance of high-field-strength magnetic resonance (MR) imaging (1.5 T) for detection of liver metastases was compared with that of computed tomography (CT). All patients (n = 52) underwent preoperative screening for metastases by means of MR imaging with T1-weighted, proton-density-weighted, and T2-weighted pulse sequences and CT scanning with unenhanced, incremental dynamic bolus-enhanced, and delayed contrast medium-enhanced techniques. Diagnostic performance was evaluated by means of receiver operating characteristic analysis in which 800 images (400 with and 400 without lesions) and five readers (4,000 observations) were used; images were obtained from patients (n = 39) in whom the same anatomic levels were available for all MR imaging and CT studies. Direct comparison between the best MR imaging technique (T2-weighted spin-echo imaging [repetition time, 2,000 msec; echo time, 70 msec]) and the best CT technique (incremental dynamic bolus CT) showed a strong trend of superiority of T2-weighted MR imaging over incremental dynamic bolus CT. No highly statistically significant difference (P greater than or equal to .01), however, was found between these two techniques.

Esophageal Neoplasms↗
PubMed1992

Differentiation of benign from malignant superficial lymphadenopathy: the role of high-resolution US.

Ultrasonography has proved a valuable tool for the detection of enlarged lymph nodes; however, differentiation between benign and malignant nodal disease remains a problem. High-frequency probes with improved spatial and contrast resolution display superficial nodes to advantage and also show the internal structure of the nodes. Ninety-four superficial nodes in patients with suspected nodal disease were examined by using 7.5-MHz probes to evaluate longitudinal-transverse diameter ratio (L/T), the central hilus, cortical widening, and size. Histologic diagnosis was obtained after sonographic examination in 73 nodes (five reactive nodes, 35 primary nodal malignancies, and 33 nodal metastases). The remaining 21 nodes regressed after either antibiotic or no therapy. Marked differences were observed among the proportions of benign and malignant nodes in terms of L/T, hilus, and cortex; the latter two structures, however, must be interpreted together. Eccentric cortical widening was seen in only malignant nodes. The distribution of nodal size was not significantly (P greater than .1) different for benign and malignant nodes. No differences were observed between primary and secondary nodal malignancies. The sonographic criteria evaluated in this study assist in the differentiation of benign from malignant superficial lymph nodes.

Adult↗
PubMed1992

The distinction between benign and malignant liver tumors on sonography: value of a hypoechoic halo.

OBJECTIVE: The purpose of this study was to determine the diagnostic value of the sonographic halo sign (defined as any hypoechoic rim in the periphery of a lesion) in distinguishing between benign and malignant isoechoic and hyperechoic liver lesions on sonography. MATERIALS AND METHODS: Sonograms of the liver in 50 patients with proved benign liver tumors and in 50 patients with proved malignant liver tumors (seven primary liver neoplasms, 43 metastases) selected during a 13-month period were retrospectively analyzed by four radiologists who had no knowledge of the patients' clinical findings or the final diagnoses. Only a single sonogram was studied in each case. The presence or absence of a hypoechoic halo on the sonogram was the only criterion for distinguishing malignant from benign hepatic lesions. RESULTS: For 95 of 100 hepatic lesions, the four radiologists were almost (three vs one) or completely (four vs zero) in agreement about the presence or absence of a hypoechoic halo. In the five cases where there were conflicting decisions (two vs two), a final decision (four vs zero) was achieved by reviewing the entire series of sonographic images. A halo could be detected in 44 malignant tumors (88%) and in only seven benign tumors (14%) (sensitivity, 88%; specificity, 86%; positive and negative predictive values, 86% and 88%, respectively). The sonographic halo sign was particularly helpful in distinguishing hemangiomas (n = 29) from metastases (n = 43) (positive and negative predictive values, 95% and 87%, respectively). CONCLUSION: The results of this study suggest that the halo sign on sonograms is useful to distinguish benign from malignant isoechoic or hyperechoic tumors.

Adult↗
PubMed1992

Pathologic explanation for hypoechoic halo seen on sonograms of malignant liver tumors: an in vitro correlative study.

OBJECTIVE: The purpose of this study was to evaluate the morphologic substrate of the hypoechoic halo seen on sonograms of malignant liver tumors. MATERIALS AND METHODS: We used sonograms and pathologic examinations to evaluate 17 cadaveric livers with macroscopic tumors (three primary liver tumors, 14 metastases). During sonography (3.5 and 5.0 MHz), a representative section plane was marked, and the same section was examined histologically. Emphasis was placed on the architecture of the tumor and the morphology of the periphery of the tumor that could account for the hypoechoic halo seen on sonograms. RESULTS: In 13 of 17 hepatic tumors, a hypoechoic halo was detected on sonograms. Histopathologic examination showed an intratumoral rim consisting of proliferating tumor cells in 12 cases and an extratumoral rim of compressed liver parenchyma in all 13 cases. A detailed comparison of sonographic and histopathologic findings showed that the hypoechoic halo corresponded to a greater concentration of tumor cells and areas of less marked fibrosis and necrosis in the periphery of the tumors. This occurred in 11 cases. In one case, histologic studies showed that the hypoechoic rim was caused by compressed liver parenchyma. In another case, the hypoechoic halo was caused by intratumoral (cellular peripheral zone of tumor) and extratumoral (compressed liver parenchyma) components. All four tumors without a halo at sonography were uniform histologically. CONCLUSION: The sonographic halo seen on sonograms of malignant liver tumors seems to be caused predominantly by a zone of proliferating tumor in the periphery of the lesion.

Adenocarcinoma↗
PubMed1991

[The potentials and limits of percutaneous needle biopsy in the histological classification of malignant tumors].

180 sonographically guided percutaneous biopsies in a variety of anatomic regions (abdomen, 110; thorax, 33; neck, 28; breast, 4; extremity, 5) were retrospectively reviewed to evaluate the percentage of correct histologic diagnoses of malignant tumours. A positive diagnosis of malignancy was established in 101 (96%) of 107 malignant tumours. A correct histologic classification was achieved in 79 (73%) of 108 malignant tumours by means of cytologic and histologic examination of the tissue acquired. Correct histologic classification of malignant tumours depends on several factors including a) needle diameter, b) location of the tumour, c) clinical constellation and, most important d) the complexion of the tumour histology. The percentage of correct histological diagnoses varied between carcinomas (79%), Hodgkin lymphomas (100%), non-Hodgkin lymphomas (45%), sarcomas (50%) and carcinoid tumours (0%). Histological classification of malignant tumours by means of percutaneous biopsy can be improved by multiple biopsies of different portions of the tumour and by using larger cutting needles.

Adolescent↗