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G Schneekloth

Publications and source records attributed to G Schneekloth.

16 recordsLinked to original sources
PubMed1990

[Selective intraoperative cholangiography].

300 consecutive cholecystectomies performed from 1984 through 1986 were studied retrospectively to answer the following questions: which are suitable preoperative indicators for selective operative cholangiography, and which is the failure rate to detect biliary concrements by selective cholangiography? Patients with a history of jaundice, suspected concrements from preoperative intravenous cholangiography or ultrasound examination, a common bile duct wider than 8 mm, and elevated serum levels of bilirubin, alkaline phosphatase, ALAT (GPT) or ASAT (GOT) all had significantly higher rates of biliary concrements. Of these indicators, preoperative radiologic studies, serum levels of ALAT (GPT) and serum levels of alkaline phosphatase showed the best sensitivity, specificity as well as positive and negative predictive value. If two criteria, preoperative radiology and serum levels of ALAT (GPT), had been used, intraoperative cholangiography would have been performed in 34% of the cases. 82% of all biliary concrements would have been detected; in 3% of all cholecystectomies, the diagnosis of concrements would have been missed. We conclude that prospective studies should be performed to better define necessity and benefit of routine operative cholangiography still widely performed today.

Cholangiography↗
PubMed1983

Measurement of liver volume by ultrasound and computed tomography.

A morphometric method to calculate liver volumes from transverse sections is evaluated (point-integrating method). In the first part of the study, 10 liver specimens were investigated by computed tomography (CT) and ultrasound (US); the calculated volumes were compared to the volumes obtained by water displacement of the organs. While CT showed an ideal agreement (r = 0.994), volumes calculated from US sections correlated less well (percentage differences from +12.5% to -9%, r = 0.915). In the second part of the study, the livers of 10 randomly selected patients were investigated by CT and US. Liver volumes were calculated using the point-integration method. Compared to the CT examination, US results show a good correlation with a correlation coefficient of r = 0.977. The point-integration method is very valuable to measure organ volumes from transverse sections. The method can be applied "offline" to photographic films, data do not have to be recorded electronically. The time required to calculate the volume of an organ is comparable to other methods.

Humans↗
PubMed1983

Computed tomography in carcinoma of esophagus and cardia.

CT scanning was performed on 36 patients with carcinoma of the esophagus or cardia. In a retrospective study, staging of esophageal malignancy, obtained by CT, was correlated with clinical data as well as endoscopic, bronchoscopic, operative, and/or autopsy findings. The results indicated that CT is a useful method for pretherapeutic staging in carcinoma of the esophagus and cardia and should be routinely performed in conjunction with conventional x-ray examination and esophagoscopy. The use of mediastinoscopy and diagnostic surgical procedures such as exploratory thoracotomy and laparotomy can be reduced.

Aged↗
PubMed1983

[Practical problems of determining liver volume from computed tomographic transverse sections].

The article confronts the traditional methods of volume calculation ("layer method"); addition of partial volumes derived from the thickness of the individual strata and their area) with a new method of including the longitudinal extension of the liver into the calculations ("topographic method"). Using a model of a liver with defined volume as basis (continuous examination every 8 mm.), various constellations of layer sequence to be expected in CT practice, are simulated and the volumes calculated from the changed data by means of both methods. It has been found that calculation of volume according to the topographic method is superior to the layer method if the respiratory position of the patient changes from layer to layer during an examination and/or if the distances between the individual layers are irregular in the course of an examination. Recommendations are given for the procedure to be followed during CT examination carried out for computing the liver volume, and for a liver volume calculation to be based on a CT examination which has already been performed.

Adult↗
PubMed1982

[The problem of metal clip artefacts in computerized tomography].

Ligature clips have proved to exhibit increasing radiodensity from titanium up to silver, steel and tantalum, according to the atomic number. clips of titanium, steel and tantalum attached to the patient's abdominal wall confirmed these findings in a plain film (n = 5), a digital scout view (n = 10) and a transverse CT scan (n = 10). The extent of the radial artefacts caused by the clips is directly related to their imaged intensity, being high for tantalum and low for steel and titanium. Because of the poor visualization of the titanium clips on the plain film, the authors recommend steel clips for the clinical test which appears to be necessary in view of the possible concomitant artefacts that could appear due to vascular pulsation.

Silver↗
PubMed1982

Computed tomography of intraperitoneal abscesses.

Eighty-seven patients with the clinical suspicion of an intraperitoneal abscess were examined by computed tomography. In 83 of these patients CT gave true positive or true negative results in reference to the diagnosis of local intraperitoneal fluids. The final diagnosis confirmed 28 abscesses in 26 patients. Most of these abscesses were in the left subphrenic space, the right subphrenic space, the right anterior subhepatic space, and the pelvis. The morphological criteria for intraperitoneal abscesses, shown by CT, are defined. Direct signs include form, impression on nonintestinal organs, density value, gas collection, pyogenic membrane, and infiltration in surrounding tissue. Indirect signs include ascites and pleural effusion and/or pulmonary infiltration. Differential diagnostic problems of intraperitoneal abscesses are discussed.

Abscess↗
PubMed1982

[Computer tomographic guided fine needle puncture of abdominal masses].

CT-guided fine-needle aspiration biopsy was carried out in 177 patients with proven intra-, retro- or extraperitoneal lesions. This method verified the diagnosis in 89/132 cases (66%) with malignant neoplasia, metastases and recurrent malignant tumors. In 45 patients with benign or inflammatory lesions of the intra- and retroperitoneal space, fine-needle puncture showed a purulent liquid, inflammatory altered cell elements or a positive bacteriological result. The success of CT fine-needle puncture depends mainly on the examiner's experience, the exact localization of the needle, and careful handling of the cytological material. Fine-needle puncture should be applied simultaneously with CT when an undefined space-occupying lesion is present. Unsuccessful sonography is an indication for CT-guided fine-needle puncture.

Abdominal Neoplasms↗
PubMed1981

[Sonography in pericardial effusion (author's transl)].

The examination technique, results and diagnostic value of sonography were evaluated in a retrospective study of 70 patients with pericardial effusion. Small effusions of less than 100 cc can be detected by observing a separation of the epicardium from the pericardium. With larger effusions sonography allows an approximate estimate of the volume. Since ultrasonography is non-invasive, and since it has a very high diagnostic accuracy and only few false-negative findings, it is the method of choice for the examination of patients suspected of having a pericardial effusion.

Adult↗
PubMed1979

[Value of sonography in the diagnosis of obscure cholestasis].

A retrospective study has been conducted in 36 cholestatic patients to determine the diagnostic accuracy of ultrasonography in preliminary differentiation of obstructive from non-obstructive hepato-biliary disease. Due to the high rate of correct biliary duct caliber evaluation, ultrasonography has proved itself an excellent screening method in patients with cholestasis of uncertain origin. The choice of the subsequent more invasive diagnostic examinations (ERC, PTC, laparoscopy) depends on the ultrasonic findings.

Biliary Tract↗
PubMed1978

[The vessels of the retropancreatic space in grey-scale-ultrasound. A contribution to the topography of the pancreas (author's transl)].

Normal pancreatic parenchyma and retropancreatic vessels can be well visualized and differentiated by grey-scale-tomography. The posterior border of the head and body of the pancreas can be defined better with the grey-scale-technique than with other ultra-sound-techniques by visualization of the retropancreatic vessels. For this purpose the venous system (portal vein, splenic vein and superior mesenteric vein) is more important than the arteries because of their closer topographic relationship to head and body of the pancreas. Identification and separation of those veins from other vascular structures is easily possible because of their constantly reliable topography and typical configuration on transverse section. The spleno-porto-vascular bundle--resembling a tadpole--should be demonstrated well enough to avoid the occasional confusion with the pancreas itself.

Humans↗
PubMed1978

[Possibilities of errors in the sonographic diagnosis of renal tumours (author's transl)].

Artefacts or not completely visualised renal contours can lead to the erroneous diagnosis "renal tumour". This false diagnosis is mostly avoidable by means of accurate examination technique. Further radiological examination will be required only in exceptional cases. Incompletely visualisable parenchymal ridges with socalled incomplete multiple kidneys frequently create the impression of an intrarenal tumour and indicate the need for further clarification. There is a relatively high degree of uncertainty in intrarenal space-occupying processes below 2.5 cm diameter, as far as structural analysis is concerned. In such cases, provided a sufficiently strong clinical and roentgenological suspicion is sustained, angiography and, if necessary, exposure, should be recommended on a rather liberal basis.

Congenital Abnormalities↗
PubMed1978

[Sonographic renal diagnosis in paediatrics (author's transl)].

Sonography is a method without risk but of high diagnostic value. Hence, it is extremely well suited for paediatric examination. In our opinion, this method should rank first among all other examination methods when clarifying inflammatory conditions of kidneys and of the efferent urinary tract, whereas in all other problems sonography continues to rank second behind the urogram. Both examinations together, which account for a diagnostic safety of more than 95%, are employed to decide whether and to what extent other and more invasive and complicated measures will have to be taken.

Abdominal Neoplasms↗
PubMed1977

[Ultrasound for differentiated carcinoma of the thyroid, autonomous adenoma and thyroiditis (author's transl)].

The article deals with a number of thyroid abnormalities which produce similar sonographic patterns, characterised by a paucity of echos of low amplitude. It concerns three more or less circumscribed changes (differentiated carcinoma of the thyroid, autonomous adenoma and focal thyroiditis) and two diffuse thyroid conditions (sub-acute and lymphocytic diffuse thyroiditis, hyperthyroidism). Carcinoma of the thyroid is of particular interest. The distinguishing features and differential diagnosis are discussed.

Diagnosis, Differential↗