Mescaline-induced psychopathological, neuropsychological, and neurometabolic effects in normal subjects: experimental psychosis as a tool for psychiatric research.

The psychological, neuropsychological, and neurometabolic effects of the hallucinogenic agent mescaline were investigated in 12 normal men who were volunteers. Mescaline produced an acute psychotic state 3 1/2-4 hr after drug intake, as measured by the Brief Psychiatric Rating Scale (BPRS) and Paranoid Depression Scale (PDS). The Assessment of Altered States of Consciousness (APZ) questionnaire revealed specific effects of mescaline in the visual system. Neuropsychological effects were studied with a face/nonface decision task with known right-hemisphere advantage, in which mescaline induced a decrease of functioning of the right hemisphere. In functional brain imaging using single photon emission computed tomography (SPECT), mescaline produced a "hyperfrontal" pattern with an emphasis on the right hemisphere, which was correlated with mescaline-induced psychotic psychopathology. Our findings question the validity of the concept of hypofrontality as an explanation for schizophrenic symptomatology. The study of psychoactive substances under controlled laboratory conditions has the methodological advantage of intraindividual control, and hence, minimal variability of data.

Optimizing renal DMSA-scintigraphy with 7-pinhole collimator.

Multiple pinhole emission tomographic imaging techniques are currently being applied to imaging of organs of a limited size. The purpose of this study was to evaluate the feasibility of this technique in kidney imaging with Tc99m-DMSA. A 7-pinhole collimator having 4.5 mm. pinhole apertures was used in conjunction with a widefield camera. Left and right kidney were imaged separately. Twelve small renal cysts with a diameter of 1 to 3.5 cm. verified by US or CAT were investigated by 7-pinhole and planar scintigraphy. Eight of 12 renal cysts were identified by 7-pinhole scintigraphy whereas only one cyst was seen by planar scintigraphy. The borderline of cysts detection was 1.5 cm. in 7-pinhole tomography. Basing on these comparative studies and experiences on many patient investigations it seems reasonable to perform renal scintigraphy with 7-pinhole tomography in a routine manner.

[Pericardial effusion: its demonstration through the epicardial fat (author's transl)]. / Perikarderguss: Hinweis durch Darstellung des epikardialen Fettgewebes.

The statement by Torrance and Kremens that it is possible to demonstrate radiologically pericardial effusions by analysing the epicardial fat layer is confirmed. Our retrospective study of 33 patients was used to determine the best technique of examination and the accuracy of the method.

[Liver scintigraphy. A comparison between scintigraphic and autopsy findings (author's transl)]. / Leberszintigraphie: Ein Vergleich zwischen szintigraphischen und autoptischen Befunden.

In 103 cases, liver metastases were found in 40 at autopsy. Of these, 34 could be further evaluated. In 15, the metastases had been demonstrated by scintigraphy. Six patients were not examined because of the rapid course of the disease, and in a further two diffuse metastases in the liver were not recognised. Of the patients in whom metastases had been missed, in eight the deposits were less than 1 cm, in another eight they were between 1 and 2 cm and, in the remaining three patients, they were between 2 and 3 cm. The findings are discussed in detail. False positive or inconclusive findings were obtained in two patients (3.2%). All thirteen cases with cirrhosis of the liver were correctly diagnosed. In four patients abnormalities of the liver parenchyma were incorrectly diagnosed (false positive). Patients with fatty livers were diagnosed equally as normal or as having parenchymal damage.

[Estimation of 131I-Iodohippurate-clearance by a simplified method using a single plasma sample (author's transl)]. / Die Bestimmung der 131J-Hippuranclearance nach einer vereinfachten Methode mit nur einer Blutentnahme.

Theoretical volumes calculated from the reciprocal of the plasma concentration after intravenous injection of 131I-Iodohippurate were compared in 95 patients with clearance values calculated by the 2-compartment-method and in 18 patients with conventional PAH-clearance. For estimating Hippurate-clearance from a single blood sampling the most favorable time is 45 min. after injection (r = 0.96; clearance < 400/ml/min.: r = 0.98). Clearance values may be derived from the formula: C = 0.4 + 7.26 V - 0.021 . V2 (V = injected activity/activity per l plasma taken 45 min. after injection). The simplicity, precision and reproducibility of the above mentioned clearance-method is emphazised.

[Indications for oral TRH in a study of 998 patients (author's transl)]. / Zur Indikation des oralen TRH-Testes.

The authors determined values for T3, T4, T7, T3RIA and basal TSH, as well as TSH stimulation after intravenous administration of TRH in 998 patients. The test was negative in 259 patients (26%); in 51 of these patients (5.1%) no clinical or laboratory reasons could be found (low- or non-responders). In this group of patients the TRH test was repeated using a hundred times greater dose orally; in 27 cases (54%) of the low- or non-responders the oral test proved positive. In total, the TRH test was positive in 76.8%, negative in 20.9% and there were 2.3% non-responders. It was concluded that the oral test is more informative than the intravenous. Since the intravenous test gives poor results in only 5.1% of euthyroid patients, the extra effort appears hardly worth while. Further, failure of the intravenous TRH tests should lead to a repetition of the TRH test using oral application before a radioiodine test is done, since this will clarify more than half the tests with negative results.

[SPECT studies with 99mTc-HMPAO in Huntington's chorea patients]. / SPECT-Untersuchungen mit 99mTc-HMPAO bei Patienten mit Huntingtonscher Chorea.

Huntington's chorea is an autosomal dominant inherited disease with a chronic course and atrophy of the corpus striatum. PET examination shows reduced glucose metabolism in the caudate nucleus. We examined seven patients with Huntington's chorea by SPECT, using 99mTc-HMPAO. All patients had cortical defects of varying severity. In addition, five patients showed increased uptake in the region of the caudate nucleus. The specific tracer uptake due to the metabolic processes in the region of the caudate nucleus in Huntington's chorea is discussed.

[Emission computed tomography of the left ventricle. Multiplanar ECG-triggered radionuclide ventriculography with a 7-pinhole collimator]. / Emissionscomputertomographie des linken Ventrikels. Multiplanare EKG-getriggerte Radionuklidventrikulographie mit dem 7-pinhole-Kollimator.

Tomographic studies and time-dependent tomograms on phantoms and patients were carried out using a 7-pinhole collimator in order to study the clinical value of ECG-triggered tomographic radionuclid ventriculography. A suitable computer programme has been developed. The results have shown that it is possible to evaluate local contraction abnormalities by this method. Using a left oblique position of the collimator (LAO [45 degrees]-cranial [15 degrees] ), emission computer tomography is aligned with the longitudinal axis of the heart. In this way, a single projection is sufficient to show the motility of the anterior and posterior walls and of the septum. Hypokinesis, akinesis or dyskinesis can be recognised visually. The localisation and extent of the defect can be determined through the 7-pinhole collimator. Reconstructed images of the triggered radionuclid scintigrams show excellent marginal definition. In the RAO projection, the left ventricle can be seen without superimposition and images obtained which equal those of a first-pass technique.

[Reinjection of 201TL in postinfarct patients so as to improve the demarcation between cicatrix and ischemia]. / Re-Injektion von 201Tl bei Postinfarktpatienten zur besseren Abgrenzung von Narbe und Ischämie.

In patients with earlier myocardial infarction the value of additional imaging after reinjection of 201Tl for better detection of ischemic myocardium was assessed. In 40 patients 40 MBq 201Tl were reinjected 24 h after stress and additional SPECT was performed 1 h later. Quantification of defect sizes showed a further reduction of 4 h redistribution defects by more than 30% in 18 patients. Comparison with clinical, electrocardiographic and scintigraphic parameters showed that none of these was sufficiently accurate for predicting additional thallium uptake after reinjection. In 22 patients with coronary angiography all 11 patients with collateralized occlusions of a coronary artery showed a reduction of the 4 h redistribution defect by > 20%, whereas all patients (5/5) with occlusions without distal collateralization had changes < 20%. This demonstrates that an improved thallium uptake after reinjection is typical of ischemic but vital myocardium.

[99mTc-2-methoxy-isobutyl-isonitrile in the diagnosis of coronary heart disease: results of a multicenter study]. / 99mTc-2-Methoxy-Isobutyl-Isonitril in der Diagnostik der koronaren Herzkrankheit: Ergebnisse einer Multizenterstudie.

A total of 226 patients was studied in a phase-III multicenter trial to compare the results of stress/rest 99mTc-MIBI with 201TI scintigraphy and/or coronary arteriography. The evaluation of planar and SPECT imaging was based on a semiquantitative visual scoring. A congruent diagnosis was generated from all planar 201TI and 99mTc-MIBI scintigrams performed in 36 patients. In 62 of 63 patients, SPECT-studies with 99mTc-MIBI and 201TI led to an identical diagnosis. In one patient a positive result was obtained with 201TI-SPECT whereas 99mTc-MIBI was negative. Segmental agreement for 1509 SPECT segments was 85.7%, for 554 planar segments it was 86.6%. In comparison to coronary arteriography, performed in 180 patients, the overall sensitivity for the correct diagnosis of coronary artery disease (CAD) was 86% for planar MIBI scintigraphy or 92% for MIBI-SPECT. Overall specificity was 100% for planar imaging and 57% for SPECT. The low specificity of MIBI-SPECT was probably due to high prevalence of CAD in this study population. In a subgroup of 43 patients, who underwent coronary angiography, identical results were found with 99mTc-MIBI and 201TI. Only one patient showed a positive scintigraphic result with both 99mTc-MIBI and 201TI without angiographically proven stenosis greater than 50% or prior myocardial infarction. Vessel sensitivities in stenosed coronary arteries (greater than 50% stenosis) were 54% for the LAD and 87% for the RCX/RCA areas with MIBI-SPECT, or 51% or 79% for planar scintigraphy, respectively. Vessel specificities for SPECT were 65% in the LAD or 52% in the RCX/RCA, or 90% or 83% in planar imaging.(ABSTRACT TRUNCATED AT 250 WORDS)

[Brachial edema after treatment of mammary carcinoma: significance of phlebography (author's transl)]. / Armödem nach behandeltem Mammakarzinom: Stellenwert der Phlebographie

The frequency of thromboses or of obstacles to the venous flow in brachial or axillary regions has been examined by a phlebographic survey of 102 patients who were treated surgically and radiotherapeutically because of cancers of the breast. Thromboses or venous obstruction were found in the 86 patients with brachial edema. Ten of the patients (12%) with brachial edema had thromboses. Further 15 suffered from an obstruction to the venous flow. The results are discussed in detail, and compared with the rather contradictory data in literature. As a consequence of this study an indication for brachial phlebography would be justified on a larger scale with patients having been treated surgically because of mammary carcinoma.