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T Geisler

Publications and source records attributed to T Geisler.

7 recordsLinked to original sources
PubMed2006

Freehand three-dimensional assessment of left ventricular volumes and ejection fraction with ultrasound contrast agent LK565.

AIMS: Accurate assessment of left ventricular function by determining left ventricular volumes and ejection fraction is important in evaluating the prognoses of patients with heart failure. Two-dimensional (2D) echocardiography suffers from low correlation with reference methods like ventriculography. Three-dimensionally (3D) assessed data have been proved to have better conformity. Endocardial border delineation remains a problem, however, especially in patients with suboptimal recordings. Few data exist on 3D-echocardiographic volumetry with ultrasound contrast agents (UCAs). We evaluated the second-generation UCA LK565 for its boundary-tracing capacities in freehand 3D echocardiography in a phase II clinical trial. Safety and efficacy of the novel contrast agent were also evaluated. METHODS AND RESULTS: Forty patients between the age of 42 and 77 were included in this trial. Left ventricular end-systolic and -diastolic volume (LVESV, LVEDV) and ejection fraction (EF) were determined by either 2D or 3D freehand second harmonic echocardiography with and without use of LK565. Parameters were compared statistically with ventriculography performed in 35 patients. Immune response to LK565 was evaluated by analysing phagocytosis capacity and kinetics of inflammatory cytokines (TNF-alpha, IL-4, IL-10, IFN-gamma). Patients were monitored for adverse events up to 72 h after application of the UCA. Calculated values for left ventricular volumes and ejection fraction correlated best for freehand 3D echocardiography in combination with LK565 (r=0.92 for LVEDV; r=0.96 for LVESV; r=0.94 for EF). Excellent left ventricular contrast enhancement was achieved for approximately 8 min. A reversible saturation of phagocytosis capacity for monocytes and neutrophils set in with a maximum peak at 6h. No significant increase in cytokine expression was observed. CONCLUSION: LK565 improves feasibility of endocardial border delineation in 3D echocardiography, leading to better correlation of left ventricular volumetry with reference methods. Efficacy and safety of LK565 are equivalent to those of conventional UCAs.

Adult↗
PubMed2004

Immunological evaluation of the new stable ultrasound contrast agent LK565: a phase one clinical trial.

BACKGROUND: Ultrasound contrast agents (UCAs) allow the enhancement of vascular definition, thereby providing more diagnostic information. LK565 is a new second-generation UCA based on synthetic polymers of aspartic acid which is eliminated from the blood stream via phagocytosis. LK565 forms very stable air-filled microspheres and is capable of repeated passage through the pulmonary capillary bed after peripheral intravenous injection. This characteristic allows examination of the cardiac function or extracardiac vessel abnormalities up to 15 minutes. METHODS: A phase one clinical study was conducted on 15 healthy volunteers to identify the development of an undesirable immune response. Phagocytosis capacity, TNF-alpha secretion, and MHC class II upregulation of monocytes was monitored, as well as microsphere specific antibody development (IgM, IgG). Furthermore, the kinetics of the activation surface markers CD69, CD25, CD71, and CD11b on leukocytes were analyzed. RESULTS: Due to LK565-metabolism the administration of the UCA led to saturation of phagocytes which was reversible after 24 hrs. Compared to positive controls neither significant TNF-alpha elevation, neither MHC class II and activation surface markers upregulation, nor specific antibody development was detectable. CONCLUSION: The administration of LK565 provides a comfortable duration of signal enhancement, esp. in echocardiography, without causing a major activation cascade or triggering an adaptive immune response. To minimize the risk of undesirable adverse events such as anaphylactoid reactions, immunological studies should be included in clinical trials for new UCAs. The use of LK565 as another new ultrasound contrast agent should be encouraged as a safe means to provide additional diagnostic information.

Adult↗
PubMed1995

[Ovarian metastasis of malignant melanoma--case report].

Malignant melanoma is a rare encounter in gynaecological practice; when it does occur it is most commonly as a primary tumor of the vulva. Primary manifestation of generalised metastatic spread in both ovaries ten years after treatment for a low risk malignant melanoma is a rare finding. In the absence of a appropriate previous history, classical histopathological methods can sometimes lead to an uncertain diagnosis. However, by permitting a combination of various markers, supplemental immunohistochemical examination will facilitate the correct diagnosis.

Biomarkers, Tumor↗