Biomedical subjects

A Bockisch

Publications and source records attributed to A Bockisch.

At least 109 records · Page 6Linked to original sources

PubMed1989

[Inhalation scintigraphy of the lung using the new ultrafine aerosol Technegas].

Evaporation of 99mTc-pertechnetate at about 2500 degrees C on a carbon surface generates an ultrafine aerosol of labelled carbon clusters. Its particle size of about 2-5 nm enables the aerosol to behave similarly to a gas regarding the ability of penetration. After inhalation, the radioactive particles adhere to the walls of the respiratory bronchioli and alveoli. The high concentration of the radioactivity in the argon carrier gas makes it possible to record a scintigram after a single deep breath. We studied four healthy volunteers and 79 patients including 34 with a tentative diagnosis of pulmonary embolism, 20 with bronchus carcinoma, and 15 with various other lung diseases. Ten of these patients were infants, the youngest being nine months old. All patients also had a perfusion scintigraphy.

Administration, Inhalation↗

PubMed1989

[The significance of testicular scintigraphy for the differential diagnosis of the acute scrotum].

Scrotal scans were performed in 100 juvenile or grown-up patients suffering from acute scrotal pain. Employing the standard equipment of a nuclear medicine department this examination which takes only a few minutes, had a very high accuracy (93%). Especially each torsion was diagnosed correctly. Quantitative analysis of the scans did not yield additional information compared to visual evaluation, and was therefore abandoned. In three patients presenting with traumatic scrotal hematoma the testicular perfusion was judged correctly posttraumatically and in follow-up scans.

Acute Disease↗

PubMed1989

Imaging of brain tumors with L-3-[123I]iodo-alpha-methyl tyrosine and SPECT.

Carbon-11-labeled amino acids have been successfully used to image brain tumors by PET. This study was undertaken to evaluate the potential of L-3-[123I]-iodo-alpha-methyl tyrosine (123IMT) for metabolic imaging of brain tumors. Ten patients (glioblastoma, oligodendroglioma, lymphoma, and metastases) had early and delayed brain SPECT with a rotating gamma camera after i.v.-injection of 200-300 MBq 123IMT. In nine patients the tumors showed intense uptake of the radiotracer. Tumor-to-brain tissue ratios were between 1.4 and 2.6. 123IMT shows potentials for monitoring the effects of brain tumor therapy.

Brain Neoplasms↗

PubMed1989

[The modification of 201Tl-SPECT of the myocardium by breast absorption].

The attenuation effect of the female breast on single-photon emission computed 201Tl-chloride myocardial tomograms (SPECT) was quantitatively evaluated in a group of 20 women. SPECT was carried out with the left breast in the normal position and after its maximal upward displacement. The count rate gain was up to 30% when the breast was raised. 201Tl-chloride myocardial SPECT often showed false lesions in the anterior wall which resulted from the attenuation of the gamma rays by the female breast. This factor is neglected in constructing the tomograms, and even if such artifacts are absent, the attenuation may adversely affect the calculated wash-out values.

Absorption↗

PubMed1988

[Nuclear medicine diagnosis of Alzheimer type dementia].

Eleven patients with Alzheimer type dementia were investigated by single-photon-emission computed tomography (SPECT) using 99mTc-hexamethylpropylene-aminoxim (HM-PAO). Nine had a typical, symmetrically reduced enrichment in the parieto-temporo-occipital area. In three of these nine patients a similar pattern was recorded additionally in the frontal, in the remaining two in the temporal or parietal region. In a semi-quantitative evaluation radioactivity concentrations in the cerebrum and cerebellum were compared. It demonstrated that there was in relation to the cerebellum a reduced concentration in seven of the eight studied cerebral regions. The relative blood flow of the parieto-temporo-occipital region was most markedly affected and in patients with Alzheimer type dementia was reduced by 25% below that of normal subjects. The results indicate that cerebral SPECT with HM-PAO is a reasonable method of investigation to confirm the diagnosis of "Alzheimer type dementia" and exclude other cerebral disease, especially if pathognomonic findings are to be obtained.

Alzheimer Disease↗

PubMed1988

Magnetic resonance (MR) imaging of prostatic tumours, a comparison with X-ray CT and transrectal sonography (TRS).

A total of 7 healthy volunteers and 31 patients have been examined clinically, by MRI, TRS, and biopsy. In those patients with established carcinoma, a CT examination was also performed. For the MRI study, a superconducting MR 2000 imager (Picker International) operated at 0.15 T was used with multiplanar SE and IR sequences. SE sequences with long echo times detected prostatitis, adenoma and carcinoma of the prostate with a high degree of sensitivity. However, at present, differentiation between adenoma, prostatitis and carcinoma is not possible with sufficient accuracy. In these studies we were unable to establish a correlation between the signal pattern and staging and/or grading of the carcinoma. Reliable diagnosis of a prostate carcinoma still requires a biopsy. Because of the high soft tissue contrast and the possibility of selecting any orientation for the plane under investigation, however, MRI represents an improvement in the preoperative diagnosis of local spread.

Aged↗

PubMed1988

[HMPAO-SPECT in cerebral seizures].

In nine patients with suspected psychogenic seizures and in three patients with proven epileptic seizures HMPAO-SPECT was performed prior to and during seizure. In the patients with later on-proven psychogenic seizures no, or only slight, changes of regional cerebral blood flow were found. Patients with proven epilepsy revealed partly normal findings interictally but during seizure a markedly increased circumscript blood flow was found in all patients. Even though PET is superior to SPECT with respect to spatial resolution, in the diagnosis of seizures HMPAO-SPECT has the advantage of enabling injection of the tracer during the seizure and the performance of the SPECT study subsequently.

Epilepsy↗

PubMed1988

[Ectopic ureterocele--diagnosis and therapy].

The ectopic ureterocele is a relatively frequent congenital abnormality of the urinary tract. Its clinical signs are often uncharacteristic. Therefore the sometimes discrete changes in the diagnostic evaluations have to be looked for. The various procedures of which the excretory urography still plays a central role are discussed with their possibilities and limitations. The removal of the mostly dysplastic upper segment with its ureter is usually the most sensible treatment. Only in rare cases, where scintigraphically and clinically the segment seems preservable, a ureteropyelostomy is indicated. The different indications for primary and secondary excision of the ureterocele itself are outlined. A minimal therapy, that does not correct the underlying anatomical abnormality like the endoscopic incision should be reserved for uroseptic emergencies.

Child↗

PubMed1988

[Comparison of 99m Tc-HMPAO-labeled leukocytes and 99m Tc-nanocolloid in osteomyelitis].

Six patients with proven or suspected osteomyelitis were studied with both 99mTc-HMPAO-labelled leukocytes and 99mTc-nanocolloid. In all cases the findings of both procedures were in good agreement. In 3 patients there was markedly increased accumulation of labelled cells and colloid, respectively. Two patients showed slightly increased accumulation of both agents and in one patient the finding was (correctly) negative. Further studies are necessary to determine whether or not colloid scintigraphy might replace the time-consuming leukocyte scintigraphy.

Adult↗

PubMed1987

[Metastases of a medullary carcinoma of the thyroid (follicular variant). Diagnosis and therapy using radioiodine].

Six years after surgery and radioiodine treatment of a medullary thyroid carcinoma a woman patient developed pulmonary metastases with radioiodine uptake. These were treated with 11.7 GBq (twice 150 mCi) 131I. Retrospective immunohistochemistry of the primary tumour revealed a mixed medullary and follicular pattern. Since it is likely that in patients having such follicular variants of medullary thyroid carcinoma the metastases are of a similar pattern, immunohistochemistry should aim at identifying follicular structure, followed by initiation of whole body scintigraphy and radioiodine treatment if appropriate.

Adult↗

PubMed1987

[Scintigraphic detection of malignancies with radioactively labelled tumor antibodies. Clinical results based on immunohistochemical research].

69 patients with different tumors (colorectal, melanoma, testicle, ovary, bladder, carcinoid, lungs) were investigated by radioimmunoscintigraphy. The corresponding antibodies or their F(ab')2 fragments against CEA (n = 30), melanoma antigen (n = 25), TPA (n = 6), beta-HCG (n = 5), HMFG-2 (n = 2) and CEA/CA 19-9 (n = 1) were selected on the basis of immunohistochemical investigations of the primary tumors. The precision was 62%, and the number of false-negative findings was 32%. Additional clinical information (detection or exclusion of a suspected recurrence) could be obtained in 22 patients. From these results, it can be concluded that the corresponding tumor antibodies should be selected on the basis of immunohistochemical investigations of the primary tumor before performing radioimmunoscintigraphy to screen for recurrences or metastases.

Antibodies, Monoclonal↗

PubMed1987

The diagnostic significance of magnetic resonance imaging in prostatic tumours.

Looking for better diagnostic methods of prostatic tumours the pelves of 38 males (22 of them suffering from prostatic carcinoma) were examined by magnetic resonance imaging (MRI). This new technique helps to distinguish between healthy and pathological prostatic tissue. It is a non-invasive method, which seems to gain improved significance in the preoperative delineation of prostatic cancer; it is a valuable tool for an accurate preoperative T-staging.

Humans↗

PubMed1986

Clinical results of immunoscintigraphy in a variety of malignant tumors with special reference to immunohistochemistry.

Radioimmunoscintigraphy was performed in 52 patients with a variety of malignant tumors (colorectal, melanoma, lung, testicular, ovarian, bladder, carcinoid). Respective antibodies or their F(ab')2 fragments against CEA (n = 23), melanoma antigen 225.28 S (n = 18), TPA (n = 4), beta HCG (n = 5) and HMFG2 (n = 2) were selected by immunohistochemistry of the primary tumor. Most patients were suspected of recurrence or of hitherto unknown distant or local metastases. Overall accuracy was 61% (32/52). False negatives amounted to 33% (17/52). Useful additional clinical information-not available by CT, ultrasonics or serum levels of tumor markers-was obtained in 17 out of 52 patients (= 33%). From these results it seems obvious that antibodies used for radioimmunoscintigraphy should be selected on the basis of immunohistochemistry.

Antibodies, Monoclonal↗

PubMed1985

[Suitability of the middle acoustic evoked potential P35 for frequency-specific measurements].

Objective audiograms (500, 1000 and 3000 Hz) have been produced by the help of the middle auditory evoked potential P35 (Fig. 3). The adjustment of the computer audiometer was optimized in such a manner that the reproducible measurement of the potential P35 was feasible even near the hearing threshold. In particular, the setting of the low and high pass filter, the shape of the auditory stimulus and the interstimulus interval have been varied. The latency of the potential was found to increase in good correlation with decreasing intensity of the tone burst. Reference curves of the sound intensity - latency dependence were derived from the examination of 13 subjects with normal hearing, aged 18 to 59 years (Fig. 4). The theoretically expected frequency specificity of the method was proved by the examination of patients suffering from a wide variety of selective hearing losses. In addition, statements on the recruitment are found to be feasible. Reports of four selected cases are presented: a labyrinthine hearing loss (Fig. 5), two acute hearing losses (Figs. 6 and 7) and a neural hearing loss (Fig. 8).

Adolescent↗

PubMed1976

[Antihemolytic effect of various benzodiazepines on human erythrocytes].

The benzodiazepines, medazepam, chlorodiazepoxyde, and oxazepam, act antihemolytically just as chloropromazine in hypotonic NaCl solution on human erythrocytes. The effect depends on concentration and is biphasic with the exception of oxazepam. The maximal antihemolytic concentrations are for medazepam 9.1-10-5 M, for chlorodiazepoxyde 4.6-10-4 M and, respectively, 9.1-10-4 M for diazepam and oxazepam. No linear correlation exists between the concentration at maximal hemolytic protection and the lipid solubility.

Anti-Anxiety Agents↗

PubMedDate not supplied

Staging and follow-up of gastrointestinal tumors with PET/CT.

Positron emission tomography (PET) is a functional imaging modality that has been documented to be useful in patient care. Oncologic PET imaging is used for a wide variety of neoplasms, mainly for staging and follow-up, differentiation of equivocal morphologic findings, therapy stratification, and monitoring. Because PET imaging is based on the physiologically mediated distribution of the administered tracer but not on anatomic information, the addition of computed tomography (CT) to PET may improve the interpretation of PET. Combined PET and CT offers several potential advantages over PET alone that may influence the clinical routine. PET/CT was introduced into clinical use only 3 years ago and has found widespread application within only 1 to 2 years. This article summarizes preliminary data of clinical applications for PET/CT in gastrointestinal tumors.

Bile Duct Neoplasms↗

PubMedDate not supplied

Whole-body fluorine-18 fluordeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) in staging of advanced uveal melanoma.

Fluorine-18 fluordeoxyglucose positron emission tomography (FDG-PET) is an useful tool in diagnosing and monitoring of malignant cutaneous melanoma. However, the feasibility and usefulness of FDG-PET in uveal melanoma is not yet established. We present a patient with suspected advanced uveal melanoma who underwent combined FDG-PET/computed tomography (CT) for staging. FDG-PET/CT images demonstrated vital intraocular tumor. Anatomical assignment of the malignancy to the choroid was possible by means of the coregistered computed tomography. Furthermore, PET revealed an unknown otherwise undetected vital liver metastasis. We conclude that combined FDG-PET/CT has potential to further improve staging and therapy planning in patients with advanced uveal melanoma.

Aged↗

PubMedDate not supplied

[Gallium scintigraphy in the diagnosis of osteomyelitis].

The results in the use of Gallium-scintigraphy for diagnosis of osteomyelitis are reported. The examined cases all had individual problems and the Gallium-67 promised additional information about the nature of the underlying bone process. Because of the different mechanisms for Gallium to accumulate in pathological bone processes it is necessary to know exactly the individual problem of the case to keep the rate of wrong positive results low. Despite of such efforts one should be cautious in using this method in the diagnosis of chronic osteomyelitis.

Adult↗