Regional lung function of non-smokers with healed spontaneous pneumothorax. A physiologic and emission radiologic study.

This study is based on investigations of 11 nonsmokers with healed spontaneous pneumothorax. Physiologic, scintigraphic and radiologic examinations were performed to determine whether they had any impairment of overall or regional lung function. Posteroanterior and lateral chest radiographic examinations revealed no abnormality. Forced expirographic study was normal, but the residual volume was increased. Ventilation was impaired and perfusion decreased in the apical region of the lungs, also the most common location of spontaneous pneumothorax. Findings are consistent with the presence of regional airway obstruction, which may cause, or at least contribute to, development of this condition.

Nonsmoking, non-alpha 1-antitrypsin deficiency-induced emphysema in nonsmokers with healed spontaneous pneumothorax, identified by computed tomography of the lungs.

This case-control study is based on an investigation of 27 nonsmoking patients with radiologically verified spontaneous pneumothorax (SP) and ten healthy never-smoker control subjects. The posteroanterior and lateral radiographs of patients and control subjects were normal. They were all submitted to the same clinical, laboratory, and radiologic examinations, including computed tomography (CT) of the lungs, with the aim of detecting any parenchymatous lung changes. Emphysema-like changes (ELCs) were detected on CT in 22 (81 percent) of the 27 patients, and if the ELC cases detected during interventional surgery are added, the frequency increases to 24/27 (89 percent). In 20 patients with unilateral SP, at least one ELC was found in 13 of the 20 SP-affected lungs, but only in five of the 20 lungs that were not diagnosed as having SP (p < 0.05). ELCs were found more frequently in the upper than in the lower lung regions (p < 0.05) and more frequently in the radiologically peripheral than in central regions (p < 0.001). No ELC was detected in the control group on CT. No alpha 1-antitrypsin deficiency was found in the 27 nonsmoking patients with radiologically verified SP who had ELCs despite the absence of these known promoters of emphysema.

Quantitative measurements of radioactive isotopes in human nasal secretion.

Four patients receiving an intravenous injection of 99mTc-pertechnetate were investigated concerning transfer of the radioisotope to the nasal secretion. The concentration of isotope in nasal secretion was in all patients found to be approximately 10 times higher than in blood. The results suggest an active transport mechanism in the glandular elements of the nasal mucosa and that they are important as source of nasal secretion during normal conditions.

Contrast enhancement with time in gliomas. Stereotactic computer tomography following contrast medium infusion.

Dynamic enhancement of astrocytomas has been investigated with CT following infusion of contrast medium. The areas of measurement corresponded with obtained stereotactic biopsies. The resulting types of enhancement are discussed in terms of a 3-compartment model. Great differences exist in the degree of enhancement of astrocytomas of grade I to II and those of grade III to IV. In the latter tumours a dynamic response appears to occur, distinctly different from that in infarctions.

75Se-methionine uptake in the pancreas. An experimental investigation in mice.

Measurements of the uptake of 75Se-methionine in the abdominal visceral organs of mice indicate that amino acids (Aminosol) significantly increase the accumulation of the isotope in pancreas. Similarly, a beneficial effect if observed on the distribution of activity between pancreas and blood, while withdrawal of food adversely affects the uptake in the pancreas and gastro-intestinal tract.

Isotope scanning with Tc99m-MDP of the spine and the costosternal junctions of patients with idiopathic scoliosis.

Bone scanning of the thoracolumbar spine and the anterior thorax was performed in 7 girls with recently diagnosed progressive thoracic idiopathic scoliosis. A reference group consisted of a group of 8 patients submitted to bone scanning for other reasons. In all 7 girls composing the scoliosis group the isotope uptake by the vertex vertebra, the 2 vertebrae above and the 2 below was homogeneous, with no areas of abnormally increased uptake. In 5 of these patients where quantitative studies were performed there was no significant difference in uptake between the vertex and the other 4 vertebrae. Nor did the 2 groups differ significantly as regards the left-right difference in uptake by the costosternal junctions. The results of this investigation confirm the observation in a preliminary study that there was no disturbance of spinal growth during the early stage of development of idiopathic thoracic scoliosis. However, the results do not support a tentative conclusion drawn on the basis of the preliminary study--namely, that the development of spinal deformity in idiopathic scoliosis might be ascribed to asymmetric longitudinal rib growth, reflected in asymmetric isotope uptake by the paired costosternal junctions. It is questionable however, whether scintigraphic scanning can provide an accurate procedure for quantitative measurement of skeletal growth of the ribs, especially in scoliotic patients.

Splenic injury due to indirect torsion.

A patient with subcapsular rupture of the spleen in association with indirect torsion trauma is reported. The spleen was surrounded by bands and adherent organs. The injury was considered to have been caused by a stretched band. In patients with hemoperitoneum, celiac angiography is advocated for diagnosis when immediate surgery is not indicated.

Contrast enhancement of cranial lesions in computed tomography.

The time course of enhancement in apparently normal brain tissue, edema and focal lesions during 30 to 60 min after intravenous injection of vascular contrast medium was evaluated in a series of 41 patients with different intracranial lesions. The attenuation of apparently normal unenhanced brain tissue varied with the level of the scan, mainly an effect of beam hardening. Different types of enhancement response are discussed in terms of a 3-compartment model. The differential diagnostic potential of contrast enhancement in the early phase needs further evaluation using instruments with short scanning time, while the late phase of enhancement must be recorded with the use of a reliable head fixation to provide reproducibility of repeat measurements.

Acute effect of an antihypertensive drug, labetalol, on uteroplacental blood flow.

The effect of a new antihypertensive drug, labetalol, on uteroplacental blood flow was determined in eight pre-eclamptic women. After injection of 0.5 mCi of 113mIn the radioactivity in the placenta was recorded by a gamma camera linked to a computer and the placental blood-flow index was calculated from the ratio between the maximum radioactivity of the isotope-accumulation curve and the rise time of the curve. Labetalol, a combined alpha- and beta-adrenoceptor antagonist was given intravenously and after 30 min a second uteroplacental blood-flow index was calculated. There was a significant mean decrease of blood pressure from 147/98 to 128/83 mmHg, but no change in uteroplacental blood-flow index, so that uteroplacental vascular resistance tended to decrease.

Comparison of uteroplacental blood flow in normal and in intrauterine growth-retarded pregnancy. Measurements with Indium-113m and a computer-linked gammacamera.

Uteroplacental blood flow was studied with a noninvasive method using indium-113m and a computer-linked gammacamera. The blood flow was determined from the ratio of the maximum and the rise time of the isotope accumulation curve of the placenta. Eight pregnancies with intrauterine growth retardation (IUGR) were compared with 11 normal pregnancies. In the IUGR group the mean placental blood flow was only 1/4 of corresponding mean values of the normal group. The difference was highly significant (p less than 0.01).

Scintigraphy of induced myocardial infarcts with 99Tcm-gluconate.

A new isotope compound, 99Tcm-gluconate, for detection of myocardial infarction has been tested in dogs. A close correlation was found between the isotope uptake measured in vivo with a gamma camera and the infarct weight of early irreversible myocardial infarcts.

Uteroplacental blood flow index in intrauterine growth retardation of fetal or maternal origin.

Uteroplacental blood flow index was determined in 30 women with intrauterine growth retardation (IUGR group) and in 26 women without fetal growth retardation (control group) during the last trimester of pregnancy. After 1 mCi (37 MBq) of indium-113m chloride had been injected intravenously the radiation was registered by a computer-linked scintillation camera positioned above the placenta during 10 s-intervals for 240 s. From the isotope accumulation curve a uteroplacental blood flow index could be calculated for each patient. The median blood flow index in the IUGR group was less than half of that in the control group. In the IUGR group the index was as low in the six women who gave birth to infants with congenital malformations as in the other 24 women in whom fetal growth retardation was due to maternal factors.

Provocation of chest pain in patients with coronary insufficiency using the vasodilator adenosine.

Chest pain provoked by intravenous injection of adenosine was compared with natural angina pectoris in five patients with ischaemic heart disease. In seven healthy subjects a possible myocardial site for provocation of the chest pain was evaluated by analysis of time delays from injection to symptoms. The healthy volunteers were given the maximum tolerable dose of adenosine intravenously, together with 99Technetium-diethylentriaminpentaacetate (99Tcm-DTPA). Chest pain started after 4.1 +/- 2.4 s and reached its maximum 8.4 +/- 4.1 s after maximum left ventricular radioactivity. The patients with a history of typical angina pectoris were given similar doses of intravenous adenosine and the provoked chest pain did not differ in quality from the patients' habitual angina pectoris. The patients did not develop electrocardiographic signs suggesting myocardial ischaemia. Heart rate and blood pressure did not indicate increased myocardial work. In conclusion, the results concur with the hypothesis that adenosine elicits angina pectoris by stimulation of intracardiac adenosine receptors.

Functional placental scintigraphy. A methodologic and clinical investigation.

A method to determine the uteroplacental blood flow in the last trimester of pregnancy is presented. After intravenous injection of 37 MBq 113Inm the radiation above the placenta was recorded in 10 s intervals for 240 s by a scintillation camera. The data are presented in a time-activity curve, in which the maximum activity is proportional to the placenta volume, rise time can be defined and the quotient maximum activity/rise time is calculated. This quotient is an index of the uteroplacental blood flow which can be used for comparison of a series of patients.

Labetalol for the treatment of hypertension in pregnancy. Pharmacokinetics and effects on the uteroplacental blood flow.

Plasma levels of labetalol were measured in 7 hypertensive pregnant women who were given 200 mg three times daily orally. The plasma concentrations were usually lower than those reported in the non-pregnant state at a comparative dose. In 5 women the ratio between fetal and maternal plasma labetalol concentrations could be calculated at parturition. The median value of this quotient was about 50%. The effect of labetalol 1 mg/kg body weight intravenously was registered with functional placental scintigraphy. Fifteen women participated. A computer-linked gamma camera above the uterus registered the radioactivity in the placental region after two intravenous bolus injections of 18.5 MBq indium-113m chloride. From the radioactivity uptake curves, uteroplacental blood flow indices could be calculated before and 30 minutes after the labetalol injection. Despite a significant reduction in maternal blood pressure, no change in uteroplacental blood flow index was found. This could indicate that the vascular resistance in the maternal placental circulation was reduced by labetalol.

Uptake of 99Tcm-gluconate and early histologic findings in induced myocardial infarcts in dogs.

A new isotope, 99Tcm-gluconate, for detection of myocardial infarction has been investigated experimentally. Great differences in isotope uptake between infarcted myocardium and normal myocardium were found in dogs. A close correlation was found between the isotope uptake and the uptake of basic fuchsin (HBFP) at microscopy in early myocardial infarcts.