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G Sialer

Publications and source records attributed to G Sialer.

9 recordsLinked to original sources
PubMed1991

Perioperative myocardial perfusion scintigraphy at rest with technetium 99m methoxyisobutylisonitrile before and after coronary bypass operations.

Eighteen patients were examined at rest by technetium 99m methoxyisobutylisonitrile (99mTc-MIBI) myocardial scintigraphy 1 day before and 1 week after aorto-coronary bypass operation with planar and single photon emission tomography (SPET) imaging. One day postoperatively, a planar scintigraph in the intensive care unit (ICU) was done. Inter-observer variability was 3.8% for all examinations and for SPET alone, 3.9%. The quality of the planar images taken under emergency conditions in the ICU was quite comparable with those taken under routine conditions. The postoperative myocardial infarction in a patient who died 6 days later could clearly be demonstrated. In 16.2% of all segments which were hypoperfused at rest on preoperative scintigraphy, an amelioration of perfusion could be shown in the 1st week after the bypass operation. 99mTc-MIBI proved to be a useful agent to assess perioperative perfusion, in the ICU as well as under standard conditions.

Adult↗
PubMed1991

Failure of MR imaging to detect reflex sympathetic dystrophy of the extremities.

Reflex sympathetic dystrophy of the extremities is a disease with a wide spectrum of clinical manifestations. It is characterized by pain, hyperthermia, and cutaneous changes and has been linked to an abnormality of regional blood flow. The disease is associated with previous injury or trauma including surgery, but also has been found in association with myocardial infarctions and tumors. The final diagnosis can be made only on the basis of the clinical course, which is characterized either by regression without sequel or the appearance of aponeurotic and tendinous retractions including bony sclerosis in the affected region occurring over many months to years. The literature and our own results show that MR imaging has high sensitivity for diagnosing transient osteoporosis of the hip, which is generally thought to be a form of reflex sympathetic dystrophy. Therefore we investigated the usefulness of MR imaging for diagnosing sympathetic dystrophy of the extremities. Twenty-five patients underwent T1- and T2-weighted MR imaging of the affected body region. They were selected on the basis of the initial clinical findings and positive findings on scintigraphy, which is known to be a sensitive, but not very specific, imaging method for sympathetic dystrophy. The final diagnosis was established on the basis of the clinical course in 17 of the 25 patients. In 10 of these, findings on MR images were completely normal, in six the MR images showed only nonspecific soft-tissue changes or bone marrow sclerosis, and in one patient they showed changes in bone marrow signal. Of the remaining eight patients without a final diagnosis of sympathetic dystrophy, MR showed soft-tissue or bone marrow alterations in six. MR imaging appears to be of little value in establishing the diagnosis of sympathetic dystrophy, but it may improve diagnostic specificity when used in conjunction with scintigraphy.

Adult↗
PubMed1990

Bitemporal hypoperfusion in transient global amnesia: 99m-Tc-HM-PAO SPECT and neuropsychological findings during and after an attack.

We report a patient who was evaluated neuropsychologically and with single photon emission computed tomography (SPECT) during and after an episode of transient global amnesia. During the attack, there was patchy retrograde amnesia and an inability to learn both verbal and non-verbal material. SPECT showed severe bitemporal hypoperfusion. Serial neuro-psychological testing documented a rapid recovery of recognition, but delayed recovery in reproduction of learned information. Recovery of spontaneous verbal and figural fluency was even further delayed. Follow up SPECT examination showed a recovered cerebral perfusion. This case supports the hypothesis that TGA is associated with transient hypoperfusion of bilateral medial-temporal brain structures and suggests an additional involvement of structures responsible for drive and initiation.

Aged↗
PubMed1980

Lateralization procedures in primary aldosteronism.

The diagnostic validity of adrenal isotopic scanning, adrenal venous aldosterone, adrenal phlebography and computed abdominal tomography (CT) was studied in 44 patients with primary aldosteronism. In all patients the diagnosis was confirmed by surgery (unilateral adrenal adenoma n = 32, bilateral adrenal hyperplasia n = 12). Both adrenal scintiscan, adrenal venous aldosterone and CT allowed in a comparable high percentage of patients (71%0 the exact classification of the adrenal lesion(s), whereas adrenal phlebography could distinguish adenoma from hyperplasia in 57%. Marked differences between the lateralization procedures, however, were observed in predicting incorrect preoperative indentification: adrenal scintiscan 29%, adrenal venous aldosterone 3%, adrenal veno-graphy 6% and CT 0%. Finally, the percentage of patients in whom no differentiation between the two main subgroups of primary aldosteronism could be obtain varied between 0% with adrenal isotopic scanning and 37% with adrenal phlebography (CT 29% and adrenal venous aldosterone 26%). Both scintiscan and adrenal venous aldosterone were not improved by the administration of dexamethasone. Our findings document that adrenal venous aldosterone determinations, adrenal isotopic scanning and computed tomography are equally valid in differentiating unilateral adenoma from bilateral adrenal hyperplasia in primary aldosteronism. However, adrenal scintiscan is hampered by a relative high percentage of incorrect results independant whether dexamethasone was used or not. Contrary, adrenal venous aldosterone and computed tomography seemed to have no or only a minor risk in assuming an incorrect classification of the adrenal lesion(s).

Adenoma↗
PubMed1979

[Radionuclide determination of the left ventricular ejection fraction under stress: comparison with angiocardiography].

Left ventricular ejection fraction (LVEF) determined by first pass radionuclide (Nucl.) and biplane contrast angiocardiography (Angio.) was compared in 62 patients with suspected coronary artery disease under resting conditions and in 32/62 patients during bicycle ergometry at identical work load. At rest both methods correlated with r = 0.81 with similar heart rates in both determinations. The mean value of LVEF (Nucl.) was lower than the mean value of LVEF (Angio.), at 50 +/- 2 (SE) % and 58 +/- 2% respectively (p less than 0.001). During exercise a significant correlation between the two methods was again found (r = 0.76). This time no difference was detected between the mean values for LVEF (50 +/- 3% [Nucl.] vs 48 +/- 2% [Angio.], n.s.), which may be explained by the higher heart rates during the invasive study (123 +/- 5/min [Angio.] vs. 108 +/- 4/min [Nucl.], p less than 0.001), resulting in a higher degree of ischemia and hence a lower LVEF. The interobserver variability did not differ between the two methods.

Adult↗
PubMed1978

[Nuclear medical determination of the ejection fraction and the regional wall movements of the left ventricle].

Left ventricular ejection fraction was determined in 114 patients by radionuclide and contrast angiocardiography. The correlation coefficient (r) amounted to 0.66. Exclusion of patients with arrhythmias and with a difference in heart rate exceeding 15 beats per minute between the two determinations of the ejection fraction increased r to 0.80 (61 patients). In patients with coronary artery disease and cardiomyopathies (n = 35), r was higher (0.88) than in patients (n = 26) with acquired valve disease or congenital heart disease (0.60). Comparison of first pass radionuclide angiocardiography and gated blood pool scanning with contrast angiocardiography in 19 patients elicited an r-value of 0.82 for the first pass method and of 0.31 for gated blood pool scanning. Visual assessment of local wall motion by gated blood pool scanning in 15 patients showed agreement with cineangiographically quantitated segmental motion (normo-, hypo- or a-kinesis) in 50 of 60 (= 83%) evaluated segments.

Angiocardiography↗
PubMed1978

[Influence of percutaneous radiation therapy upon the large salivary glands of the head: results from functional diagnostics using radionuclide techniques in 95 patients (author's transl)].

We investigated the function of the parotid and submandibular glands in normals and in patients with radiotherapy in the head neck region by scintigraphic methods. The above given doses relate to an application scheme with 200 rd 5 times per week. There is a relatively severe loss of function with small doses from 1000 to 2000 rd. After doses till 3000 rd, there is complete recovery of the gland function in about three months. After 4500 rd, there is in about 80% of the patients a complete recovery after about one year. After irradiation with 5000 or more rd, there is nearly in no person a recovery of the gland function. We did not find a compensatory increase in the function of a spared gland with compensation of irreversibly atrophic glands.

Humans↗
PubMedDate not supplied

[Nuclear medicine diagnostic localization in primary aldosteronism and Cushing syndrome].

The main indication for 131J-cholesterol scintigraphy is primary aldosteronism. The preoperative localization of aldosterone - producing adenomas may be obtained with the non-invasive NP-59 - scintigraphy in 75-85% of the patients. Idiopathic bilateral adrenal hyperplasia is diagnosed correctly in 90-100% of the cases. In Cushing's syndrome scintigraphy of the adrenal cortex is indicated only in specific cases such as very small adenomas, primary nodular adrenal hyperplasia and/or for the localization of ectopic adrenal cortex tissue. A false diagnosis may be caused by asymmetric uptake of the radioisotope in idiopathic bilateral hyperplasia or by unspecific absorption in non - adenomatous adrenal cortex tissue with symmetric uptake in patients with unilateral adenomas.

Adenoma↗