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Biomedical subjects

G Krol

Publications and source records attributed to G Krol.

65 records · Page 4Linked to original sources
PubMed1976

Analysis of butaclamol in serum by fluorescence induction.

A sensitive TLC-fluorometric method was developed for the analysis of butaclamol, a benzo[6,7]cyclohepta[1,2,3-de]-pyrido[2,1-a]isoquinoline derivative, in serum. The method involves cyclohexane extraction of serum samples followed by TLC of the concentrated extracts. The developed TLC plates were sprayed with an oxidizing reagent and heated at 110 degrees. Highly fluorescent spots were produced for butaclamol, which was well separated from metabolites and serum components. Fluorometric densitometry permitted quantitation with a sensitivity of 10 ng/spot application.

Adult↗
PubMed1975

Value and pitfalls of the lateral lung scan.

Two hundred eighty-one of 443 lung scans composed of anterior, posterior, and lateral projections (done in our hospital) demonstrated defects. In 3.9 percent of them (11 cases), the defects were delineated in the lateral views only, while in 29.2 percent (82 cases), the lateral views either outlined additional defects not appreciated on the straight views, or showed more extensive lung involvement. In the majority of instances, 56.6 percent (159 cases), the lateral views showed comparable findings and also tended to segmentally localize the defects better. However, in 10.3 percent (29 cases), defects present on the straight projections were not detected on the lateral views. Various causes that could give rise to artefactural abnormalities in the lateral lung scan and therefore inhibit its proper interpretation, are reviewed and discussed. Despite these problems, the lateral may be the only view to demonstrate abnormalities and, in fact, frequently provides additional useful information.

Humans↗
PubMedDate not supplied

Lumbosacral epidural metastases: CT evaluation and comparison with myelography.

Computerized tomography (CT) of lumbosacral region and lumbar myelograms of 100 patients with primary tumours were evaluated independently for evidence of epidural metastases. An attempt was made to predict myelographic abnormalities (or absence of such) on the basis of CT appearance at the spine and spinal canal contents. The overall accuracy of computed tomography was found to be 80%. There was a good correlation with myelography in patients without evidence of epidural lesions (79%). However, in group of patients with positive myelograms, CT was rather unreliable with high number of false negative studies (50%).

Epidural Space↗
PubMedDate not supplied

MR imaging of the cranial meninges with emphasis on contrast enhancement and meningeal carcinomatosis.

MR imaging was used to investigate normal and abnormal meningeal enhancement, with an emphasis on meningeal carcinomatosis. Three groups of patients were studied on a 1.5-T system. In group 1, the normal meninges were examined in 20 patients and were found to show fine linear enhancement in short segments, especially in a parasagittal distribution. In group 2, all gadolinium-enhanced head scans were reviewed retrospectively. Abnormal meningeal enhancement was detected in 52 patients. In some of these, the enhancement was associated with pathologic conditions of the meninges, including leptomeningeal tumor and meningeal infections and other inflammatory conditions; in others the enhancement was adjacent to subdural hematomas, subacute infarcts, and skull lesions, such as metastases or postoperative defects. In group 3, 30 cases of meningeal carcinomatosis were studied prospectively. Enhancement was seen in approximately two-thirds of cases and usually was quite diffuse and applied to the inner table of the skull. Frank nodules were seen less often. Contrast-enhanced CT was equal to MR in the detection of nodules but was nearly always unable to show diffuse meningeal enhancement against the inner table of the skull. Contrast-enhanced MR was more sensitive than contrast-enhanced CT in the examination of normal and abnormal meninges. Abnormal findings, such as meningeal carcinomatosis, were demonstrated more often by MR than by CT.

Adolescent↗
PubMedDate not supplied

Dural sinus thrombosis: verification with spin-echo techniques.

Although MR imaging is being used increasingly to detect dural sinus thrombosis, accurate evaluation of images has often been hindered by the presence of artifacts, especially flow-related enhancement, that may simulate intraluminal clot. We tried an approach with spin-echo techniques to eliminate flow-induced artifacts and, thus, facilitate the diagnosis of dural sinus thrombosis. In this investigation, a nonselective single-section spin-echo verification method was used as a prototype of this approach. Both patients and an experimental flow phantom were used to test the validity of this concept. Clinically, thrombosis was seen to persist as isointense or highly intense signal in the vascular lumina with the specialized sequence, while flow-related artifacts were replaced by hypointense signal, but not by signal void. These same changes were examined both quantitatively and qualitatively in the flow phantom by using varying velocities of flow. Although our clinical investigation concerns suspected dural sinus thrombosis, the principles of these specialized spin-echo techniques can be applied successfully throughout the head to eliminate certain flow-related artifacts.

Adolescent↗