Biomedical subjects

Sonja Buhmann

Publications and source records attributed to Sonja Buhmann.

7 recordsLinked to original sources

PubMed2006

Assessment of colonic transit time using MRI: a feasibility study.

The aim of this pilot study was to evaluate a new, non-invasive examination method using MRI for the quantification of the colonic transit time after oral administration of gadolinium-saline solution filled capsules. Healthy volunteers without previous or acute symptoms of gastrointestinal disorders were enrolled. After a 3-day diet for the standardization of gastrocolonic content the volunteers swallowed five Gd-DTPA/saline 0.9%-filled capsules. Seven different concentrations of Gd-DTPA/saline 0.9% solution between 1:0 and 0:1 were tested in a dilution series. Following ingestion of capsules, coronal Flash T1 and True Fisp sequences using a 1.5 Tesla system were obtained at 0 h, 3 h, 6 h, 12 h, 24 h, 36 h and 60 h. Sequences were analyzed by two independent experts for locating the capsules. Overall colonic transit time was separately analyzed for both genders. Fifteen healthy volunteers (7 females, 8 males; mean age 34+/-13 years) were enrolled. The phantom study provided the best contrast in both the T1-and T2-weighted sequences defining a ratio of 1:10 for Gd-DTPA/saline 0.9% solution. The mean transit time accounted for 41+/-9 h in women and for 31+/-10 h in men. MRI is an adequate method for the assessment of colonic transit time offering the advantages of no exposure to radiation, short examination time, possible dynamic evaluation of the transit and the practicability in terms of a future adoption to clinical routine.

Administration, Oral↗

PubMed2006

A rare differential diagnosis to occupational neck pain: bilateral stylohyoid syndrome.

Chronic neck pain is widely prevalent and a common source of disability in the working-age population. Etiology of chronic neck pain includes neck sprain, mechanical or muscular neck pain, myofascial pain syndrome, postural neck pain as well as pain due to degenerative changes. We report the case of a 42 year old secretary, complaining about a longer history of neck pain and limited movement of the cervical spine. Surprisingly, the adequate radiologic examination revealed a bilateral ossification of the stylohyoid ligament complex. Her symptoms remained intractable from conservative treatment consisting of anti-inflammatory medication as well as physical therapy. Hence the patient was admitted to surgical resection of the ossified stylohyoid ligament complex. Afterwards she was free of any complaints and went back to work. Therefore, ossification of the stylohyoid ligament complex causing severe neck pain and movement disorder should be regarded as a rare differential diagnosis of occupational related neck pain.

Journal Article↗

PubMed2006

Dual-source CT cardiac imaging: initial experience.

The relation of heart rate and image quality in the depiction of coronary arteries, heart valves and myocardium was assessed on a dual-source computed tomography system (DSCT). Coronary CT angiography was performed on a DSCT (Somatom Definition, Siemens) with high concentration contrast media (Iopromide, Ultravist 370, Schering) in 24 patients with heart rates between 44 and 92 beats per minute. Images were reconstructed over the whole cardiac cycle in 10% steps. Two readers independently assessed the image quality with regard to the diagnostic evaluation of right and left coronary artery, heart valves and left ventricular myocardium for the assessment of vessel wall changes, coronary stenoses, valve morphology and function and ventricular function on a three point grading scale. The image quality ratings at the optimal reconstruction interval were 1.24+/-0.42 for the right and 1.09+/-0.27 for the left coronary artery. A reconstruction of diagnostic systolic and diastolic images is possible for a wide range of heart rates, allowing also a functional evaluation of valves and myocardium. Dual-source CT offers very robust diagnostic image quality in a wide range of heart rates. The high temporal resolution now also makes a functional evaluation of the heart valves and myocardium possible.

Algorithms↗

PubMed2006

Intrathecal and systemic concentration of NT-proBNP in patients with severe traumatic brain injury.

Outcome of patients suffering from traumatic brain injury (TBI) depends on the development of secondary brain damage. In this context, recent studies underlined the role of the natriuretic peptides- atrial natriuretic peptide and brain natriuretic peptide (BNP)-in aneurysmatic subarachnoidal hemorrhage (SAH). Especially BNP correlates with intracranial pressure and clinical outcome after SAH. Since its role in TBI remains unclear, the intracranial and systemic concentrations of N-terminal (NT)-proBNP were analyzed in patients suffering from severe TBI. We measured NT-proBNP levels in cerebrospinal fluid (CSF) and serum of 14 patients suffering from severe TBI (GCS 15 mm Hg (n=6), the serum (800+/-150 pg/mL) and CSF levels (55+/-9 pg/mL) of NT-proBNP were significantly increased after 24 h, as compared to patients with ICP 15 mm Hg. Further studies are currently performed to elucidate the physiologic role of NT-proBNP in TBI.

Adult↗

PubMed2006

Significance of Elecsys S100 immunoassay for real-time assessment of traumatic brain damage in multiple trauma patients.

BACKGROUND: The neuroprotein S100 released into the circulation has been suggested as a reliable marker for primary brain damage. However, safe identification of relevant traumatic brain injury (TBI) may possibly be hampered by S100 release from peripheral tissue. The objective of this study was to measure early S100 levels using the Elecsys S100 immunoassay for real-time assessment of severe TBI in multiple trauma. METHODS: Consecutively admitted multiple trauma patients (injury severity score >or=16 points) were stratified according to the results of the initial cerebral computed tomography (CCT) examination. S100 serum levels were determined at admission and at 6, 12, 24, 48 and 72 h after trauma. Data were correlated to creatine phosphokinase (CK) and lactate dehydrogenase (LDH) serum levels. Using receiver operating characteristic (ROC) analysis, the discriminating power of S100 measurement was calculated for the detection of CCT+ findings. RESULTS: Median S100 levels of CCT+ patients (n=9; 37 years) decreased from 3.30 microg/L at admission to 0.41 microg/L 72 h after trauma. They revealed no significant differences to CCT- patients (n=18; 44 years), but remained elevated compared to controls. Median CK and LDH levels correlated with the corresponding S100 levels during the first 24 h after trauma. ROC analysis displayed a maximum area under the curve of only 0.653 at 12 h after trauma. No significant difference was calculated for the differentiation between CCT+ and CCT- patients. CONCLUSIONS: Measurements of S100 serum levels using the Elecsys S100 immunoassay are not reliable for the real-time detection of severe TBI in multiple trauma patients. Due to soft tissue trauma or bone fractures, S100 is mainly released from peripheral sources such as adipocytes or skeletal muscle cells.

Adult↗

PubMed2005

Role of MRI for the diagnosis and prognosis of multiple myeloma.

For the correct staging of patients with multiple myeloma sensitive detection is mandatory in order to estimate prognosis and to decide for adequate therapy. Magnetic resonance imaging (MRI) is superior to radiography for both, focal and diffuse involvement. Five different infiltration patterns can be differentiated: (1) normal appearance of bone marrow despite minor microscopic plasma cell infiltration, (2) focal involvement, (3) homogeneous diffuse infiltration, (4) combined diffuse and focal infiltration, (5) "salt-and-pepper"-pattern with inhomogeneous bone marrow with interposition of fat islands. For the fast and complete assessment of all patterns a combination of a T1-weighted spin echo sequence and a fat suppression technique should be employed. The focal involvement is clearly demonstrated as areas of high signal intensity on, e.g. STIR images. Diffuse involvement is best detected on unenhanced T1-weighted SE sequences and it manifests as homogeneous signal reduction. It can be quantified objectively by calculation of the percentage of signal intensity increase after contrast material injection. With parallel imaging and special coil devices, such as total imaging matrix (Siemens systems, Avanto) a "screening" of the whole red bone marrow as for myeloma infiltration is possible within a reasonable time. Patients without bone marrow infiltration have a significantly longer survival than patients with bone marrow infiltration in MRI at the time of diagnosis. However, even in stage I disease (Durie and Salmon) and negative X-ray films bone marrow infiltration in MRI may be detected in 29-50% of patients. Those patients typically show an earlier disease progression. Recently, MRI has been implemented in the clinical staging of patients with multiple myeloma. MRI may also monitor response to therapy. Signs of good response in cases with focal involvement are: reduction of signal intensity on T2-weighted spin echo images, lack or rim-like enhancement after contrast material injection or even a normalisation of bone marrow signal. In case of diffuse involvement a partly patchy reconversion to fatty marrow can be seen.

Bone Marrow↗

PubMed2005

Assessment of large bowel motility by cine magnetic resonance imaging using two different prokinetic agents: a feasibility study.

OBJECTIVES: We sought to assess large bowel motility, induced by 2 prokinetic agents, senna tea and erythromycin, using functional cine magnetic resonance imaging (MRI). MATERIALS AND METHODS: Twelve volunteers underwent functional cine MRI before and after the administration of senna tea or erythromycin. The protocol consisted of 2 sets of repeated measurements using coronal T2-weighted HASTE sequences, adjusted to the course of the colon. For the assessment of large bowel motility, the changes of the luminal diameter were measured at 5 defined locations in the ascending, transverse, and descending colon. RESULTS: In all examined volunteers after senna tea, the mean number of significant changes in the ascending colon was 8.6 and after erythromycin, 7.2. In the transverse colon, 9.6 diameters changed significantly for senna tea and 7.2 for erythromycin. In the descending colon, 6.6 diameters changed after senna tea and 7.2 after erythromycin. CONCLUSION: Senna tea and erythromycin proved to induce large bowel motility; senna tea was more effective. Functional cine MRI is a reliable, noninvasive method for the assessment of colonic motility.

Administration, Oral↗