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K Küper

Publications and source records attributed to K Küper.

At least 37 records · Page 2Linked to original sources
PubMed1988

[Nuclear magnetic resonance imaging in gynecology. An evaluation of its current applications].

The authors present a research carried out by the Universities of Essen, Tubingen (RFA) and Grenoble, France, on the use of magnetic resonance imaging (M.R.I.) in gynaecology. After clarifying our knowledge of the normal anatomy of the pelvis and of the tissular characteristics of MRI the principal indications are discussed and set out. The investigation is shown to be particularly valuable in working out the aetiology, the volume and the spread of a pelvic mass whether it is benign or malignant when it is important to be exact in finding the origin of the tumour. This research has been illustrated by analysing 35 case histories including 28 malignant tumours. A second study was carried out on 30 cases of cancer of the cervix. In this field MRI is the only test that can be carried out before therapy to give a tridimensional assessment of the size of the tumour and whether it has spread into the parametrium. The visual impressions obtained by MRI illustrate each chapter: of the gynaecological anatomy, of the pathology, in cancers of the cervix, in pelvic masses and particularly in ovarian tumours.

Female↗
PubMed1987

[1st results of the diagnosis of focal liver and spleen lesions using gradient echo sequences].

15 healthy subjects and 39 patients with focal liver and spleen lesions were examined via MR tomography at 1.5 tesla. Gradient field echos at small angle excitation (less than 90 degrees) were employed. The imaging time per layer was 10 seconds so that rapid imaging could be carried out at respiratory standstill. This enabled visualisation of liver and spleen without interference by breathing artifacts and with accurate localisation. Focal lesions can be imaged best at low flip-angle pulses (liver) or low to medium-angle pulses (spleen). The primary liver cell carcinoma is visualised as an inhomogeneous structure with similar signal intensity as the surrounding tissue. All other examined liver lesions (metastases, haemangiomas, lymphatic infiltrates, echinococcus cysts, FNH, gummae) showed greater signal intensity than the remaining organ at small angle excitation. Furthermore, contrast reversals were seen at medium-angle pulses. Contrariwise, with the exception of the light-coloured spleen infarcts, spleen lesions (lymphatic infiltrate, Boeck's disease or sarcoidosis) appeared darker at all excitation angles than the surrounding tissue.

Humans↗
PubMed1987

[Potentials of nuclear magnetic resonance tomographic diagnosis of the adrenals. Initial experience using a Helmholtz surface coil].

In order to obtain optimum spatial resolution in the adrenal glands, images were obtained using Helmholtz surface coils and respiratory gating. In addition to normal controls, 9 patients with space-occupying lesions were examined (4 metastases, 3 adenomas, 2 phaeochromocytomas). It was found that tissue-specific appearances were associated only with phaeochromocytomas, depending on the high signal intensity on their T2 sequences.

Adenoma↗
PubMed1986

[Microsurgical bile duct anastomosis: animal experiment and clinical study].

In 10 Göttingen-minipigs an end-to-end anastomosis of the normal common bile duct was accomplished under the microscope with 11/0 Polygalactin-sutures. Biliary flow was controlled by serum concentration of alkaline phosphatase, by cholangiography and by dynamic hepato-biliary scintigraphy 2 weeks, and 3 and 6 months after the operation. Anastomoses were judged by macroscopic, microscopic and scanning electronmicroscopic examination 6 or 12 months postoperatively. The anastomoses presented no stenosis at all, only a light periductal fibrosis with intact luminal epithelium. Alkaline phosphatases and cholangiography showed a normal pattern, the scintigraphy presented dyskinesia after 2 weeks and normal flow at the later controls. After a microsurgical operation one patient showed a normal anastomosis after 6 months. A biliary anastomosis should be made by microscope in all patients with a long life span and unchanged bile duct wall in spite of the more difficult operation.

Adult↗
PubMed1986

[Necessity for ECG triggering in digital subtraction angiography. Construction of a simple trigger device].

Movement unsharpness during digital subtraction angiography of the aortic arch and supra-aortic vessels can be avoided by means of ECG gating. The usual techniques resulted in exposures during the phase of least cardiac movement. The relatively long exposure time of about 60 to 300 msec caused marginal blurring during the exposure. An ECG-triggered device is described which produces short exposure times for the mask and filled frame during identical cardiac phases. An example with and without ECG gating shows marked improvement in detail rendering. The design of an ECG-triggered device with digitally adjustable delay and freedom from interference is described.

Angiography↗
PubMed1986

[Imaging of prostatic cancer by 1.5 Tesla nuclear resonance tomography].

Twenty-two patients with histologically confirmed carcinomas of the prostate were examined by nuclear magnetic resonance, using a 1.5 Tesla magnet (stage T1: one patient, T2: eight patients, T3: six patients, T4: seven patients). In 19 out of the 21 patients in stages T2 to T4, the tumour showed a specific signal intensity. In 12 cases, the tumour signal was more intense than from a normal prostate when using medium repetition and echo delay times; in 19 cases, multi-echo sequences with increasing echo delay time (30 to 240 ms) and long repetition times (usually 1600 ms) showed less reduction in signal intensity than surrounding structures (except urine). Unlike computed tomography, 1.5 Tesla MR is able to demonstrate carcinomas confined to the prostate. Demonstration of infiltration is possible with MR with great accuracy because of the ability to obtain images in three planes and because of the accurate rendering of soft tissue detail. In particular, MR differentiates between stages T2 and T3 more clearly than does CT. The best demonstration of anatomical structures in the true pelvis is achieved with a repetition time of 800 ms and an echo delay time of 30 ms, the best demonstration of tumour with corresponding 1600 ms and 120 ms. The effect of catheters in the bladder, or previous transurethral resection on the MR images is discussed.

Aged↗
PubMed1986

[1.5 Tesla nuclear magnetic resonance tomographic studies of bladder cancer].

MR tomography was performed in 15 patients with urologically prediagnosed carcinoma of the urinary bladder. A field strength of 1.5 Tesla yields excellent morphological resolution of site and contrast. The results are compared with CT and--wherever available--with the pathological anatomic preparations. MR is often superior to x-ray computed tomography in demonstrating polypous carcinomas of the bladder and those producing thickening of the wall, since MR offers the possibility of performing coronary and sagittal cuts. In individual cases, MR can supply definite information on the depth of infiltration into the bladder wall and into perivesical structures; such findings agree with those obtained with cystectomy preparations. The contrast behaviour of the tumours and adjacent structures depends strongly on the measurement parameters employed with the high-strength field technique of 1.5 Tesla used in this study. MR echo sequences using different measurement parameters are useful in delineating the tumour contours against adjacent structures such as prostate, seminal vesicles, perivesical fat, urine and to differentiate the tumour from the healthy bladder wall.

Humans↗
PubMed1985

[Value of MR tomography vs. CT in the diagnosis of rectal carcinoma and its recurrence].

The value of NMR tomography for the diagnosis of carcinoma of the rectum and of recurrences has been studied, using a 1.5 Tesla NMR apparatus and comparing the results with high resolution CT. There were five patients with a histologically proven primary tumour, eighteen patients with a recurrence and five patients who had had a rectal carcinoma removed, where there was no evidence of recurrence. By obtaining images in three planes, NMR showed the true tumour extent in all cases and was superior to CT in the diagnosis of the primary tumour (in four patients out of five) and in showing recurrences (in five out of eighteen patients). NMR also had advantages in demonstrating lymph node enlargement in the pelvis, where difficulties are often encountered using CT. Early experience with tissue characterisation indicates that it is possible to diagnose rectal tumours confined to that organ. These are usually missed by CT. CT is superior to NMR in demonstrating destructive lesions in bone. Early clinical experience suggests that NMR is a further advance in the early diagnosis of carcinoma of the rectum and of recurrences.

Aged↗
PubMed1985

[Nuclear spin tomography of the male pelvis. Methods, anatomy and initial clinical results].

A pilot study of MRI was carried out on three normal male volunteers and 15 patients with tumours in the prostate or bladder. One advantage of the method is the ability to obtain images in three planes, without moving the patient. It is therefore possible for the first time to demonstrate lesions in the base of the bladder in their cranio-caudal extent. Tissue contrast of MRI, using long sequences with suitable proton or T2-weighted images is better than with CT and provides more accurate diagnosis. Even non-expansive tumours within the gland can be differentiated from normal glandular tissue. It has been noted that carcinoma of the prostate in the T2-mode provides an increased signal, whereas tumours of the bladder look dark. Up to a point, tissue characterisation may be possible.

Aged↗
PubMed1982

[Radiological biliary tract diagnosis after cholecystectomy (author's transl)].

Fifty-three patients with biliary symptoms were studied at least four years after cholecystectomy by isotope techniques. There was a highly significant correlation between symptoms and disturbances of bile flow, such as dyskinesia or obstruction. There was no correlation with serum enzyme levels such as gamma-GT, alkaline phosphatase, bilirubin or transaminases. Measurements of the diameter of the bile duct on cholangiograms provided no evidence of obstruction up to 15 mm., although a diameter in excess of 10 mm, made obstruction likely. The upper value for "normal" bile flow derived from hilar flow curves of patients without dyskinesia showed a half value period of 27.5 minutes. The disturbances of flow demonstrated by isotope methods in the presence of typical symptoms, and without other pathological findings, indicate a pre-clinical stage of a partly compensated bilio dynamic insufficiency. Where there is no morphological evidence of biliary obstruction, one must assume inflammatory changes round the papilla of Vater; these are frequent even in normal biliary tracts and almost always present after cholecystectomy. Quantitative hepato-biliary scintigraphy is the most reliable method for objective measurement of disturbances of bile flow and make it possible to avoid the vague diagnosis of "post-cholecystectomy syndrome".

Alanine Transaminase↗
PubMed1982

[Radiological investigation of the bile ducts following cholecystectomy. Paper III: Determination of the diameter of the common bile duct by isotope methods (author's transl)].

The diameter of the common bile duct can be determined by means of quantitative hepato-biliary functional scintigraphy to an accuracy of +/- 2 mm. It is necessary to keep the conditions of the test constant, such as constant regions of interest and size of region. A common bile duct diameter greater than 10 mm. is suggestive of biliary obstruction, diameters above 15 mm. are definite proof. For the demonstration of post-hepatic obstruction, the hilar flow curve is confirmatory. Peristalsis of the common bile duct, which is an unlikely phenomenon in view of the anatomic studies of the muscle in the bile duct, cannot be demonstrated in this way.

Cholecystectomy↗
PubMed1981

[Value of scintigraphic examination methods with 99mTechnetium in injuries of the epiphyseal cartilage (author's transl)].

The value of scintigraphic examinations of injuries involving the epiphyseal plate is to be seen to ensure the correct diagnosis of the lesions type I and type V according to Salter and Harris. Further on the results of these scintigraphic examinations allow a better planning of the therapeutic procedure. Experimental findings in rabbits succeeded to predict the seriousness and an early prognosis. The disturbances of the epiphyseal blood flow can be diagnosed by 99m Tc-O4 labeled erythrocytes and 99m Tc-O4 labeled albumin microspheres. 99m Tc-MDP skeletal scintigraphy gives the information at which time the repair is done and full weight bearing is possible.

Animals↗
PubMed1980

[Quantitative whole-body bone scintigraphy. I. Methodology (author's transl)].

Quantitative whole-body bone scintigraphy is a method for evaluating digital bone scans. Its principles are: use of a double detector scanner and correction of attenuation and organ thickness effects in the scan; its results: calculation of whole-body activity, relation of bone, soft tissue and organ activity, distribution of the activity in single regions of the skeleton expressed as a percentage. The mean error of the results of 10%. By comparison with a standardized normal scan a local concentration factor for focal and diffuse bone alterations expressing quantitatively increased bone metabolism. The calculation is made automatically by computer. Further papers will report on the application of the method to the evaluation of the kinetics of bone seekers and on clinical experiences.

Bone and Bones↗