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At least 253 records · Page 14Linked to original sources

PubMed2004

Dynamic radioisotope scintigraphy for gastric banding adjustment.

BACKGROUND: Gastric banding is today a common restrictive procedure to treat morbid obesity. After operation, adjustment of the band is required to adequately restrict food intake, allowing better results. The aim of this study was to evaluate the results of a unique method of adjustment using dynamic radioisotope scintigraphy. METHODS: 40 patients after Laparoscopic Adjustable Gastric Banding (LAGB) were prospectively divided into 2 equal groups, and the results of adjustment analyzed using the conventional method of fluoroscopic image and barium swallow (FA Group), and our proposed new method of dynamic radioisotope scintigraphy (DRS Group) using Tc99-phytate labeled plain yogurt. RESULTS: After 6 months follow-up, the FA group lost 12.34%, while the DRS group lost 20.34% of their initial weight. In the FA group, we found that 95% of the patients needed re-adjustments versus only 25% in the DRS group (P <0.0001). Vomiting was more frequent in the FA group than in the DRS group, mean 0.65 and 0.2, respectively (P < 0.009). The radiation exposure was 4 times higher in the FA group, but the cost of the 2 adjustment procedures was similar. CONCLUSION: DRS is a more physiologically friendly and accurate method of gastric banding adjustment than the conventional barium swallow adjustment; it also results in a better weight loss during the first 6 months after operation.

Adult↗

PubMed2000

Intracranial hypotension due to cerebrospinal fluid leakage detected by radioisotope cisternography.

Seven patients, six females and one male aged 26 to 39 years old, presented with headache in the upright posture, which was completely relieved in the recumbent posture. Radioisotope cisternography with technetium-99m-human serum albumin detected cerebrospinal fluid (CSF) leakage at the cervicothoracic level in six patients, and at the high cervical level in one patient. The diagnosis was intracranial hypotension due to spontaneous CSF leakage. Complete bed rest for more than 2 weeks resulted in complete resolution of the headache in all patients, and follow-up cisternography showed no leakage. Radioisotope cisternography is useful for the diagnosis of spontaneous CSF leakage, and complete bed rest for more than 2 weeks may be the best method of treatment.

Adult↗

PubMed1975

Quantitative analysis of radioisotopic angiography in trophoblastic neoplasia.

The diagnostic significance of radioisotopic angiography in the clinical management of trophoblastic neoplasia was studied by analyzing the patterns of radioisotope (RI)-dynamic curve obtained by processing sequential image with a computer, and an attempt was made to express numerically the size of tumors present in vivo. It was demonstrated that the total activities of RI in the abnormal phase of RI-dynamic curves in trophoblastic neoplasia were closely correlated with the sizes of the intrauterine tumors actually resected.

Angiography↗

PubMedDate not supplied

A non-radioisotopic human natural killer cell assay using rhodamine-123 fluorescent dye as labelling probe.

A non-radioisotopic method for assessment of human natural killer (NK) cell activity in peripheral blood mononuclear cells (PBMC) was established by labelling K562 erythroleukemia target cells with a fluorescent dye, rhodamine-123 (Rh-123). The labelling and assay conditions were determined for minimizing spontaneous release (SR). In order to investigate whether NK activity assessed by measuring Rh-123 release agrees with the activity determined by a 51Cr release assay, the NK activity of PBMC was measured simultaneously by both assay methods. Statistical analysis demonstrates that NK activities determined by Rh-123 release correlate well with those measured by 51Cr release. The Rh-123 release assay under the conditions determined was found to be applicable to measurement of the enhanced NK activity resulting from pretreatment of effector leukocytes with interferon-alpha. It is concluded that the Rh-123 release assay with use of K-562 labelled target cells is practical for the assessment of human NK activity in laboratories where use of radioisotopes is not permitted or undesirable.

Chromium↗

PubMed1977

[Computer processing of radioisotope images. Hybrid processing system].

A hydrid type image file and processing system are devised by the author to file and the radioisotope image processing with analog display. This system has some functions as follows: 1) Ten thousand images can be stored in 60 feets length video-tape-recorder (VTR) tape. 2) Maximum of an image on the VTR tape is within 15 sec. 3) An image display enabled by the analog memory, which has brightness more than 15 gray levels. 4) By using the analog memories, effective image processing can be done by the small computer. 5) Many signal sources can be inputted into the hybrid system. This system can be applied many fields to both routine works and multi-purpose radioisotope image processing.

Computers, Hybrid↗

PubMedDate not supplied

Telomerase activity in gliomas with the use of non-radioisotopic and semi-quantitative procedure for terminal repeat amplification protocol.

To study the role of telomerase in the pathogenesis of different grades and subtype of gliomas, telomerase activity in 31 gliomas was assessed with the use of non-radioisotopic and semi-quantitative procedures for the terminal repeat amplification protocol in this study. Among the samples were 17 glioblastoma multiformes (GBMs); 4 anaplastic astrocytomas (AAs); 5 astrocytomas (ASs); 1 ependymoblastoma (EPB); 2 ependymomas (EPs); 1 oligodendroglioma (OG) and 1 medulloblastoma (MB). Postive telomerase activity was detected in 9 of 17 GBMs (53%), 1 of 4 AAs (25%), 1 of 5 ASs (20%), 1 of 1 EPB (100%), and in positive controls, T 98G and KE-1. Weakly positive activity was detected in 2 of 3 AAs (66%) and 2 of 5 ASs (40%). No telomerase activity was detected in 8 of 17 GBMs (47%), 1 of 4 AAs (25%), 2 of 5 AS (40%), 2 of 2 (100%) EPs, 1 of 1 OG (100%), 1 of 1 MB (100%) and normal brain tissue. We defined telomerase expression as positive and weakly positive cases. The percentage of telomerase activity expression in gliomas tended to correlate with tumour grade in spite of histopathology of tumours. These results indicated that the telomerase activity of gliomas may be used as a tumour marker and that the activation of telomerase should correlate with initiation and malignant progression of gliomas. In addition, non-radioisotopic and semi-quantitative procedure for the terminal repeat amplification protocol appears to be the most suitable to detect telomerase activity expression in small neurosurgical specimens.

Adult↗

PubMed1979

The radioisotope spleen scan in the assessment of patients with suspected spleen trauma.

The radioisotope spleen scan was reviewed in 29 patients with suspected trauma of the spleen who had been admitted for observation to a surgical ward. At the time of the study, all patients had stable pulse rates and blood pressures. The scans of six patients showed space defects and, of these, splenic injury was subsequently proven operatively in five patients. As a detector of splenic trauma, the radionuclide scan proved to be reliable. Although the findings of radioisotope scanning are not specific for trauma, the interpretation of the scan in conjunction with other observations increases the accuracy of diagnosis.

Adolescent↗

PubMed1976

Diagnosis of Meckel's diverticulum by radioisotope scanning.

The clinical illness observed in a 5-month-old infant with Meckel's diverticulum is described. A sodium pertechnetate radioisotope scan was employed to confirm the clinical impression. The technical procedure, evaluation, and importance of the radioisotope study is discussed.

Humans↗

PubMed1974

INTRACORPOREAL HEAT DISSIPATION FROM A RADIOISOTOPE-POWERED ARTIFICIAL HEART.

The feasibility of radioisotope-fueled circulatory support systems depends on the ability of the body to dissipate the reject heat from the power source driving the blood pump as well as to tolerate chronic intracorporeal radiation. Our studies have focused on the use of the circulating blood as a heat sink. Initial in vivo heat transfer studies utilized straight tube heat exchangers (electrically and radioisotope energized) to replace a segment of the descending aorta. More recent studies have used a left ventricular assist pump as a blood-cooled heat exchanger. This approach minimizes trauma, does not increase the area of prosthetic interface with the blood, and minimizes system volume. Heat rejected from the thermal engine (vapor or gas cycle) is transported from the nuclear power source in the abdomen to the pump in the thoracic cavity via hydraulic lines. Adjacent tissue is protected from the fuel capsule temperature (900 to 1200 degrees F) by vacuum foil insulation and polyurethane foam. The in vivo thermal management problems have been studied using a simulated thermal system (STS) which approximates the heat rejection and thermal transport mechanisms of the nuclear circulatory support systems under development by NHLI. Electric heaters simulate the reject heat from the thermal engines. These studies have been essential in establishing the location, suspension, surgical procedures, and postoperative care for implanting prototype nuclear heart assist systems in calves. The pump has a thermal impedance of 0.12 degrees C/watt. Analysis of the STS data in terms of an electrical analog model implies a heat transfer coefficient of 4.7 x 10(-3) watt/cm(2) degrees C in the abdomen compared to a value of 14.9 x 10(-3) watt/cm(2) degrees C from the heat exchanger plenum into the diaphragm.

Journal Article↗

PubMed1976

[X-ray contrast and radioisotope angiography in tumors of the neck].

Comparative results of angiography and radioisotope scintigraphy with technetium (Tc 99 m) in 38 patients having different jugular tumors are reported. Both methods were found to correlate well with respect to the estimation of tutor blood supply. Radioisotope scintigraphy is a more simple, physiological and practically safe method of investigation, and the former should be recommended for estimating the degree of tumors vascularization, the state of brain circulation and also in cases when angiography proves to be unfeasible.

Adenoma↗

PubMedDate not supplied

Aspects of the thyroid gland vascularization in young organisms (a morphological and radioisotope-based study).

The thyroid gland vascularization has been studied on 58 pieces belonging to young organisms (human and animal) by means of both morphometric methods (macro- and microscopic) and injection of radioisotopes (86Rb). The statistical-mathematical study of the dimensional values characterizing the thyroid vascular branch at different levels assumed for study allowed to determine the thyroid central area as the best vascularized of the thyroid parenchyma. Estimating the specific activity and the absorption constant value of the 86Rb in the vascular wall and the glandular parenchyma, the radioisotope-based study attests the data obtained morphologically. By the simultaneous injection of 86Rb into strychnine, the pharmacodynamic study shows a more prominent reduction of the 86Rb absorption constant value in the distal area of the gland as compared to its central one and the blank batch.

Aging↗

PubMedDate not supplied

[Radioisotope cisternography in the diagnosis of subarachnoid cysts].

Two cases of subarachnoid cysts are presented. Radioisotope cisternography proved successful in the diagnosis of this disorder. CT-scan and surgery confirmed diagnostic value of the radioisotope cisternography. It may be useful in case of inability to use CT-scan, being safe and valuable.

Adolescent↗

PubMed1990

[Clinical study of radioisotopic splenoportography in portal hypertension].

Radioisotopic splenoportography was performed in 55 patients with portal hypertension, in whom 52 had various degrees of esophagogastric varices, and in 20 patients without portal hypertension. In the patients with varices, collateral images were obtained in 50 patients (96%) by this method and no image was obtained in the patients without varices. The rate of positively imaged collaterals was as follows: Esophageal varices 69%, the left gastric vein 85%, the short gastric veins 48%, RI stasis in esophagogastric region 65%, the azygos vein 46%, the subclavian vein 25%, the para-umbilical veins 46%, splenorenal /gastrorenal shunts 19%, the inferior mesenteric vein 17%, the left intercostal veins 6%, and Arantius's duct 4%. These rates were superior to that obtained from the conventional transarterial portography. There were some correlations between RI-images by this method and clinical and laboratory findings; patients with ascending collaterals alone tended to have extensive and severe varices and higher rate of bleeding, on the other hand, variceal bleeding was not found and episodes of portosystemic encephalopathy frequently occurred in patients with descending collaterals alone. After successful sclerotherapy, RI-images of esophageal varices disappeared in 92% of the patients. Radioisotopic splenoportography appears to be a useful diagnostic and follow-up modality for patients with portal hypertension and esophagogastric varices.

Collateral Circulation↗

PubMed1989

Radioisotope penile plethysmography: a technique for evaluating corpora cavernosal blood flow during early tumescence.

Radioisotope penile plethysmography is a nuclear medicine technique which assists in the evaluation of patients with erectile dysfunction. This technique attempts to noninvasively quantitate penile corpora cavernosal blood flow during early penile tumescence using technetium-99m-labeled red blood cells. Penile images and counts were acquired in a steady-state blood-pool phase prior to and after the administration of intracorporal papaverine. Penile counts, images, and time-activity curves were computer analyzed in order to determine peak corporal flow and volume changes. Peak corporal flow rates were compared to arterial integrity (determined by angiography) and venosinusoidal corporal leak (determined by cavernosometry). Peak corporal flow correlated well with arterial integrity (r = 0.91) but did not correlate with venosinusoidal leak parameters (r = 0.01). This report focuses on the methodology and the assumptions which form the foundation of this technique. The strong correlation of peak corporal flow and angiography suggests that radioisotope penile plethysmography could prove useful in the evaluation of arterial inflow disorders in patients with erectile dysfunction.

Adult↗

PubMed1978

Radioisotopic diagnosis and quantitation of left to right shunts in childhood and adolescence.

In 187 patients (141 adults and 46 children) left to right shunts were assessed using quantitative radionuclide angiography. After injection of 99mTc into the femoral vein time activity curves were registered over both lungs and the heart (Ohio Nuclear Camera, ON SIGMA 400, 110, HP 5407 computer). Using a modified gamma function area ratio technique the shunt sizes were calculated. The radioisotopic method allows a precise quantitation of left to right shunts ranging from 15--80%. There was a good agreement between the shunt sizes calculated by the radioisotopic method and oximetry or dye-dilution at cardiac catheterization (adults r = 0,87, children r = 0,85). The shunts sizes assessed with this nontraumatic method appear sufficiently reliable to be a real alternative to conventional techniques in screening for shunts.

Adolescent↗

PubMed1984

Radioisotope-decay model of carcinogenesis: multistep process in the formation of original single tumor cells induced by 3-methylcholanthrene in mice.

The times of origin of fibrosarcomas induced with 3-methylcholanthrene in mice were analyzed mathematically. Histograms of the rates of formation of original single tumor cells plotted against the time after carcinogen treatment fitted a two-step exponential decay function. This model was named a radioisotope-decay model by analogy with the multistep decay of radioisotopes. The half-lives of the initial and intermediate transient states were determined for three tumor groups, and were found to be 23-29 days for both states. The present study indicates the involvement of at least two steps in the establishment of tumors, even with a complete carcinogen.

Animals↗

PubMedDate not supplied

[Evaluation of bilio-intestinal anastomoses using radioisotope cholangiography].

In patients subjected to bilio-intestinal anastomosis as treatment of several diseases of the biliary tract and the Oddi's sphincter, with some frequency have symptoms that make suspect that the anastomosis is stenosed. The experience obtained in the evaluation of 8 cases is presented. The method used was radioisotopic cholangiography, with the administration of pyridoxiphenylalanine labeled with 99m-Technetium. Serial images were obtained in Polaroid film. In three of the eight patients, an obstruction of the principal bile duct was shown. After the operation, there was normal patency of the anastomosis. In the other cases, there was normal patency of the anastomosis, and the symptoms were due to other causes. We consider the radioisotopic cholangiography as the method of election in the study of these patients, as the results may indicate a surgical re-intervention, avoid another harmful method or make unnecessary another operation.

Biliary Tract↗

PubMedDate not supplied

[Diagnostic value of radioisotope cisternography in low-pressure hydrocephalus syndrome].

In the light of pneumoencephalographic investigations and radioisotope scinticysternography carried out in 22 patients with clinical manifestations suggesting the syndrome of Hakim the authors analyse the diagnostic usefulness of both methods. In all cases PEG demonstrated dilatation of the ventricular system, in 10 cases radioisotope cisternography showed abnormal passage of the cerebrospinal fluid, and in 8 of these cases ventricular reflux was found lasting at least 24 hours, while in 2 other cases absorption of the cerebrospinal fluid was impaired. On the basis of this material the authors believe that in cases of presence of ventricular reflux this investigation is very important for undertaking the decision of surgical treatment, besides that, the authors think that despite normal scintigraphic pattern in early stage of the disease the investigation should be repeated after from 10 to 20 months, since clinical symptoms may precede disturbances of cerebrospinal fluid passage detectable in cisternographic investigation.

Adult↗