0000000000073596

AUTHOR

Klaus Hahn

Age 0–6 Months

research product

Age 4–5 Years

research product

Age 15–17 Years

research product

SPECT Bone scintigraphy of benign and malignant lesions of the spine

70 patients were examined with planar and SPECT bone scintigraphy. SPECT proved to be superior over planar bone scanning for imaging of traumatic, inflammatory, and malignant bone lesions. SPECT provides three-dimensional information and, therefore, delineates the exact location and extension of lesions. It also has a higher sensitivity than planar bone scintigraphy. The three-dimensional bone scan generates complementary diagnostic information which often facilitates an adequate therapy protocol.

research product

Age 2–3 Years

research product

Technetium-99m mercaptoacetyltriglycine clearance: reference values for infants and children.

Six hundred and thirty-nine clearance studies performed in children aged 7 days to 19 years utilizing technetium-99m mercaptoacetyltriglycine (MAG 3) were retrospectively analysed. Standardized conditions for the investigation included: parenteral hydration (60 ml/hxm2 body surface) in addition to normal oral fluid intake, weight-related dose of99mTc-MAG 3 (1 MBq/kg body weight, minimum 15 MBq) and calculation of clearance according to Bubeck et al. Of the 513 children, 169 included in this analysis could be classified as “normal” with regard to their renal function. Normal kidney function was judged by the following criteria: normal GFR for age, normal tubular function (absence of proteinu…

research product

Age 9–10 Years

research product

The value of nuclear medicine for the diagnosis of spine diseases.

Nuclear medicine examinations hold an important position in the diagnosis of diseases of the spine. During the last decade, decisive progress has been made in the field of instrumentation and radiopharmaceutical techniques: the use of high resolution collimators and the introduction of emission computer tomography as examples of improved instrumentation as well as 99m-Technetium red blood cell labelling as a new radiopharmaceutical technique. These present some of the developments responsible for the growing importance of scintigraphical diagnosis. Inflammatory processes of the vertebrae and the surrounding soft tissues can be detected or excluded with high reliability by the use of radionu…

research product

Age 14–15 Years

research product

Age 10–11 Years

research product

Age 1–2 Years

research product

Prevention of deep vein thrombosis in neurosurgical patients: a prospective double-blind comparison of two prophylactic regimen.

In a prospective, randomized, double-blind investigation of anticoagulant agents for prevention of deep vein thrombosis in patients undergoing operations at the lumbar-vertebral disc, 179 patients were randomly allocated to two groups. 87 patients received a fixed combination of low-molecular weight heparin 1,500 U-aPTT plus dihydroergotamine 0.5 mg (LMWH/DHE) once a day and additionally one injection of placebo per day, 92 patients received a fixed combination of sodium heparin 5,000 U plus dihydroergotamine 0.5 mg (HDHE) twice a day. Treatment was initiated two hours preoperatively in both groups and continued for at least seven days. Deep vein thrombosis (DVT), detected by the 125Iodine-…

research product

Benzodiazepinrezeptordarstellung mit JOMAZENIL-SPECT

Die Darstellung der Benzodiazepin-Rezeptordichte (BZD) mit der Single- Photonen-Emissions-Computertomographie (SPECT) wurde durch die Synthese des neuen Radioliganden JOMAZENIL ermoglicht. JOMAZENIL entspricht dem mit Jod-123 markierten Benzodiazepin-Antagonisten Flumazenil und zeichnet sich durch eine hochspezifische Bindung an zentralen BZ-Rezeptoren aus. Verdrangungsexperimente zeigten, das 90–110 Minuten p.i. ca. 80% der Aktivitat der spezifischen Bindung entsprechen [1].

research product

Determination of the technetium-99m mercaptoacetyltriglycine plasma clearance in children by means of a single blood sample: a multicentre study

A multicentre European study was undertaken in order to determine a reasonable algorithm allowing the determination of overall technetium-99m mercaptoacetyltriglycine clearance using a single blood sample. Employing multiple blood sample clearance as a reference method, it was shown that an acceptable estimation of the MAG3 renal clearance could be obtained using a blood sample taken at any time between 30 and 40 min after tracer injection. After correction for body surface area, comparison of clearance determined using (a) the single blood sample and (b) the multiple blood samples provided a coefficient of correlation of 0.949 and an SEE of 27 ml/min. This algorithm is valid for clearance …

research product

Age 17–22 Years

research product

Comparison of131I-metaiodobenzylguanidine scintigraphy with urinary and plasma catecholamine determinations in the diagnosis of pheochromocytoma

In a retrospective study of 31 patients with suspected pheochromocytoma we examined the preoperative results of 131I-metaiodobenzylguanidine (131-I-MIBG) scintigraphy and a fluorimetric urine catecholamine determination test. An additional radioenzymatic plasma catecholamine determination test was performed in 25 patients. In 14 of the 31 patients the diagnosis of pheochromocytoma was later histologically confirmed. In the remaining 17 patients the suspected diagnosis was finally rejected after a clinical decision had been made on the basis of clinical history, symptoms, laboratory and imaging tests. 131-I-MIBG scintigraphy apparently had a very high specificity (no false-positive results a…

research product

Age 12–13 Years

research product

Age 13–14 Years

research product

Age 11–12 Years

research product

Somatostatin-Rezeptor-Szintigraphie bei endokriner Orbitopathie

Somatostatin receptor scintigraphy with 111In-labeled octreotide proves to be a very sensitive diagnostic tool for evaluation of inflammative activity in endocrine ophthalmopathy (EO). The results of somatostatin receptor scintigraphy (SRS) in 40 patients with EO show a high orbital accumulation of 111In-octreotide in clinically active EO (4 h-median/orbit-brain-ratio: 12.6; controls 4 h-median: 5.8) Patients with clinically inactive EO (4 h-median: 7.1) show a similar orbital accumulation of radioactivity compared to controls. 5 patients with active orbital myositis also revealed an even higher orbital accumulation of radioactivity (4 h-median: 42.3). The diagnostic value of SRS lies in it…

research product

IBZM-SPECT bei Neuroleptikatherapie

Mit IBZM — einem mit Jod-123 markierten Benzamid — ist es erstmalig moglich, die Dopamin-D2-Rezeptoren mit der Single-Photonen-Emissions-Computertomographie (SPECT) darzustellen. Das trotz der fehlenden ab-soluten Quantifizierung mit SPECT diese Methode hilfreich sein kann fur die Messung der D2-Rezeptoren, wurde schon von der Arbeitsgruppe von Brucke [1] dargestellt. Gegenstand unserer eigenen Studien war die Untersuchung der D2-Rezeptorbesetzung (RB) unter Haloperidol, Benperidol und Clozapin im Zusammenhang mit klinischen Daten und Prolaktinspiegeln.

research product

Age 5–6 Years

research product

Age 6–12 Months

research product

Prolactin plasma levels and D2-dopamine receptor occupancy measured with IBZM-SPECT

By the application of 123([123I]IBZM), an iodine-labelled dopamine D2-receptor antagonist, brain D2 receptors in humans can be visualized with single photon emission computed tomography (SPECT). The ratio of IBZM binding to striatal regions versus binding to frontal cortex (ST/FC ratio) provided a semiquantitative measurement of D2 receptor binding in the striatum. This study investigated the relationship between receptor occupancy and plasma prolactin levels in 12 male patients treated with haloperidol, benperidol or clozapine. Prolactin levels were positively correlated with D2 receptor occupancy, reflecting at least in part a comparable dopamine receptor antagonism in different dopaminer…

research product

Age 3–4 Years

research product

Age 6–7 Years

research product

Szintigraphie adrenerger Tumoren mit 131J-meta-Benzylguanidin

Pheochromocytoma scanning using 131J-meta-benzylguanidine was done in one patient with metastasizing paraganglioma, one patient with multiple endocrine neoplasia type IIb. No activity of tumour tissue could be demonstrated in the patient with metastasizing paraganglioma, whereas the pheochromocytoma could be clearly defined in the patient with multiple endocrine neoplasia type IIa. The female with multiple endocrine neoplasia type IIb showed a suspect space-occupying lesion of the left adrenal using computed tomography. Pheochromocytoma could be excluded by 131J-benzylguanidine scanning, selective estimation of catecholamines in adrenal venous blood as well as the glucagon stimulation and c…

research product

Age 7–8 Years

research product

[123I]IBZM SPECT in patients treated with typical and atypical neuroleptics: relationship to drug plasma levels and extrapyramidal side effects

[123I]Iodobenzamide (IBZM) is an iodine-labeled dopamine receptor ligand and can be used to visualize brain D2 receptors in humans with single photon emission computerized tomography (SPECT). The ratio of striatal IBZM uptake to uptake in frontal cortex (ST/FC ratio) represents a semiquantitative measure of D2 receptor binding in the striatum. Our study sample included six patients treated with haloperidol (3.0-8.0 mg/day orally; one patient with an average of 0.9 mg/day intramuscularly), five patients with benperidol (9.0-15.0 mg/day orally) and nine patients treated with clozapine (200.0-600.0 mg/day orally). Typical neuroleptics (TNs) and atypical neuroleptics (ANs) were significantly di…

research product

Immunszintigraphie und -therapie

research product

Age 8–9 Years

research product

A new principle to normalize plasma concentrations allowing single-sample clearance determinations in both children and adults.

A sufficiently accurate quantification of renal function requiring only one plasma sample without an additional gamma-camera study has, until now, only been possible in adults. A new principle will be presented here allowing the universal application of known algorithms, regardless of the clearance substance used, by normalizing the plasma concentrations with respect to the individual body dimensions of the patients - for infants as well as for adults. In this respect, algorithms are developed for clearance determinations using technetium-99m mercaptoacetyltriglycine (99mTc-MAG3), which are based on steady-state studies as the reference. They allow the calculation of quantitative clearance …

research product

RCBF-quantification with 99mTc-HMPAO-SPECT: theory and first results.

The activity concentrations of 99mTc-HMPAO in brain after intravenous injection were evaluated in 25 patients using SPECT. With additional first pass studies of heart and brain with the short lived isotope 195mAu, the cardiac output and the mean cerebral transit times of the patients were measured a short time before the HMPAO injection. The time dependence of 99mTc-HMPAO activity in the brain was registered during the first 5 min after injection over both hemispheres. Using a simplified three compartment model it was possible to calculate the mean retention fraction of HMPAO in brain from the time activity curves. It could be shown that the regional cerebral blood flow in ml/min per 100 g …

research product