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Objectives: To describe the imaging features of nephroblastomatosis with US, CT and MR, to point out characteristics of differentiation between nephrogenic rests (NR) and Wilms' tumour (WT) and to determine the most appropriate imaging modality., Materials and Methods: We reviewed the US, CT and MR images of 29 cases of histopathologically confirmed nephroblastomatosis sent to our department for reference evaluation (German nephroblastoma study). The series included 17 kidneys with NR, 6 kidneys with WT and 32 kidneys with both NR and WT., Results: NR presented as multinodular, peripheral, cortical lesions, the diffuse form of distribution being less common. Foci were homogeneous and of low echogenicity, density or signal intensity. The lesions were most clearly depicted with contrast-enhanced CT and T1-weighted (T1-W) MR images. Lesions smaller than 1 cm were rarely identified by US. The most reliable criterion to differentiate NR from WT was their homogeneity., Conclusions: Contrast-enhanced CT and T1-W MR images are of similar potential and superior to US in the diagnosis of nephroblastomatosis. Due to the significant radiation dose of serial CT, MR imaging should be the method of choice wherever it is available. The cost-effectiveness and availability of US makes it ideal for serial follow-up of known lesions.

The most effective whole-body screening test for bone metastases is the radionuclide bone scan. Conventional radiography is the best modality for characterizing metastatic lesions. Furthermore, conventional radiographs are useful for depicting impending or early pathologic fractures. The radiographic sensitivity depends on the extent, location and type of bone metastases. Therefore, normal radiographs in patients with either a positive bone scan or persistent, unexplained pain must be suspect. In these cases CT may establish the diagnosis. However, metastatic lesions in the marrow space without architectural changes in the surrounding bone can be detected only by MRI. The use of CT is also helpful in determining the local extent of bone destruction and extension into the surrounding soft tissues when planning surgery or radiotherapy.

In a conventional radiographic skeletal survey of 90 hemodialyzed patients, 28% (25 patients) showed renal osteopathy; 27 patients (30%) had periarticular bone cysts and 3 patients (3%) presented radiological evidence of destructive spondylarthropathy. The bone cysts were most commonly identified in the carpal bones and around the hips and shoulders; destructive spondylarthropathy was seen in the cervical and lumbar spine. Whereas characteristic radiographic changes of renal osteodystrophy could already be identified in the 1st year of dialysis, periarticular bone cysts occurred at the earliest after 2 years, most frequently after 5 years of dialysis. Destructive spondylarthropathy was seen after more than 10 years of dialysis. A positive correlation between these bone lesions and secondary hyperparathyreoidism, dialysis membranes or renal diseases was not found.

Dialysis-related amyloidosis is characterized clinically by the carpal tunnel syndrome, pain and swelling of joints. These alterations are due to amyloid deposits in the carpal tunnel, in the synovia, ligaments and bones. It has been shown that beta 2m is the major component of this amyloidosis. Serum and urine concentration of beta 2m are markedly elevated in chronic renal failure due to failure of filtration and lack of metabolism by the renal tubular epithelium. beta 2m-derived amyloid is identified by immunohistochemistry using antibodies derived against beta 2m. Radiology shows cyst-like periarticular bone defects, destructive arthropathy and spondylarthropathy.

The angiofollicular lymphoid hyperplasia, first described by Castleman, is a benign lymphoma. The authors report a very rare case of Castleman lymphoma in the parotid gland. The tumor was successfully irradiated with 40 Gy fast electrons. Treatment planning and therapy monitoring were done by means of ultrasound and computed tomography.

According to the international SIOP 9 study preoperative chemotherapy for patients between 6 months and 16 years old is a major component of the therapeutic management of Wilms' tumour. Prior to treatment, the diagnosis is established by diagnostic imaging alone, without biopsy. This study was therefore undertaken to verify the accuracy of diagnostic imaging in the German GPO study group. Between July 1988 and November 1990, 156 patients with known histology were registered in the study centre. Of these patients, 67% (105/156) received preoperative chemotherapy. The diagnosis was initially established by US, TVP and CT, and in some cases MRT without prior biopsy. Of these preoperatively treated patients, 92.4% (97/105) had Wilms' tumour or one of its variants. Five patients had a different malignant tumour. Three cases, i.e. 2.8% of the preoperatively treated patients or 1.9% of all registered patients with known histology, had benign tumours of the kidney. Morphologically, the Wilms' tumour was revealed by a characteristic inhomogeneity in sonography and the CT scan. The inhomogeneity in the CT scan increased following injection of contrast medium. Intratumoral bleeding and cystic areas were observed frequently in the native scan. Calcifications were seen in 5% of the cases. The predictive value of pretherapeutic diagnostic imaging was good enough to justify instituting chemotherapy without diagnostic biopsy. It is still difficult in diagnostic imaging to differentiate the very rare benign cystic nephroma from malignant nephroblastoma. Intravenous pyelography proved to be the best method for distinguishing extrarenal from renal tumours.

The substantial information conveyed by conventional radiodiagnostics of pathological alterations of the facial skull is shown in 243 patients examined by conventional radiodiagnostic means and by computerised tomography. Except in case of special demands, conventional tomography has to be preferred in routine diagnostics of the facial skull as a primary method supplying an answer to the most important questions at a lower cost and in a shorter time.

The 5 years' survival rate of all cancer patients is 35-45%. In that survival rate radiotherapy takes part in 15%. By further development of radiological methods and techniques radiotherapy gains significance in the recent time. Optimizing radiation planning and tactics, all modern imaging techniques are applied consequently. The radiotherapist must be able to asses their immanent specifity which should remain object of the radiological training, even if separated into therapy and diagnostics. Dose distribution is calculated by computer; three-dimensional planning is done in tumors of the mediastinum, oesophagus carcinoma and paraaortic lymphomas. Critical description of radiation techniques, results, problems and prognoses are given by results in tumors of the epipharynx and gastric cancer. After-loading, done until now only in gynaecological tumors, is performed in recurrences of pharyngeal tumors by individually shaped applicators. Reducing the number of therapy failures as well as possible, the application of higher tumor doses, new kinds of rays as neutrons and combinations with physical and chemical methods is outlined. Modifications of radiation volumes are discussed, especially the irradiation of the complete abdomen in ovarian cancer, the irradiation of the complete body surface by electrons in mycosis fungoides, and the total body irradiation prior to autologue bone marrow transplantation. Modifications of fractionation are shown in short-time radiation of bone metastases and single-time radiation of brain lesions. Low penetrating electron therapy facilitates intraoperative single-time irradiation. Because of higher biological efficiency neutrons and heavy ions allow to irradiate low sensible tumors or recurrences embedded in fibrotic tissue respectively. The combination with hyperthermia yields good results in tumors of the head and neck with better local response and total remissions of 59%. There are potentials in synchronising with chemotherapeutics. Remissions of different duration were achieved in 190 patients. Because of neutrotoxicity there are still problems in applicating radiosensitizers. New methods are applied treating endocrine active tumors by labelled hormone precursers.

The authors report on a 31-year old female patient with recurrent renal colic since 1981 because of bilateral renal angiomyolipomas. The value of different diagnostic methods of imaging (ultrasonography, IVP, CT, angiography) with regard to the differential diagnosis and their probability of error are discussed. CT follow-up is recommended for all patients not subjected to surgical treatment.

The authors report on a 26 year old female patient suffering for years of upper abdominal pain caused by adenomyomatosis of the gallbladder. The different types of cholecystopathy are demonstrated, the decisive diagnostic criteria shown, and the results of diagnostic imaging (cholecystography/ultrasonography) discussed.

Ninety patients with liver metastases (68 colorectal carcinomas, 22 breast carcinomas) were examined by triphasic angio-CT. This included demonstration of the entire liver after a bolus-like injection of contrast. Originally, the metastases were hypodense, but showed four patterns of contrast enhancement. Quantitative evaluation of the mammary carcinomas showed a marked increase in density during the bolus phase, with similar contrast values in the liver and at the centre and edge of the metastasis at ten minutes after the injection. Colorectal carcinomas showed only slight increase in density after contrast injection. The difference in density between the centre and the periphery of the metastasis was still present on later images. This finding indicates that there are differences in the vascularisation of these metastases.

The diagnostic relevance of the various radiological examination methods - skeleton scintigraphy, conventional x-ray film, computed tomography, sonography and magnetic resonance - was analysed on the basis of an examination of 4765 clinically or scintigraphically suspect skeleton segments in order to arrive at an effective but also economically justifiable diagnostic approach. Conventional skeleton scintigraphy should be employed as the first method of choice, since it has a sensitivity of 93% and is hence very suitable as a searching tool. To differentiate benign and malignant lesions it is absolutely imperative to conduct at the same time a x-ray control of any abnormal accumulation of nuclides, or of parts of the skeleton that display signs or symptoms. Conventional x-ray film diagnosis enabled correct diagnosis of the type of disease in 95% of the cases. In its capacity as a complementary examination method, computed tomography enabled correct diagnosis in 52% of the cases that had remained roentgenologically unclear. A pathological bone scintigram without any x-ray or CT correlate must be considered as being suspect of metastases if trauma is absent. Magnetic resonance proved to be the most sensitive method in identifying malignant infiltrations of the medullary space in two patients suffering from a clearly delineated pain syndrome with normal x-ray and CT findings. Sonography proved superior in detecting extraosseous tumour portions. The value of angiography is the preoperative vascular imaging of metastases of the possibility of performing therapeutic embolisation or intraarterial drug therapy.

The value of sonography for diagnosis and therapy planning of bone metastases is shown in 110 affected skeletal regions (60 patients with malignant diseases). Whereas sonography is inferior to conventional x-ray in respect of defects of the spongiosa, it is equal with regard to defects of the cortical layer but superior in respect of changes of the periosteum and the surrounding soft tissue. Moreover, there is an excellent correlation (97%) between pain and the reaction of periosteum and soft-tissue layer. Because of the three dimensional representation of the tumourous processes sonography has proved valuable in radiotherapy planning (field size, radiation method, risk organs etc.).

The indication and efficiency of various radiological examination methods in relapsing infections of the urinary tract, as well as the complications of such infections, are described, and characteristic and pathognomical findings are demonstrated. The diagnostic accuracy of the individual imaging methods depends on the site, size, and density of the pathological process. Accurate diagnosis also requires the incorporation of clinical findings including those established by means of clinical pathology setups.

Metastasis of the stomach wall in mammary cancer as first sign of disease spread 9 years after removal of the primary carcinoma is reported. The diagnosis was proven by surgical biopsy with demonstration of positive hormone receptors. The radiological and CT signs of infiltration of the stomach wall without mucosal destruction is a rare but typical finding in tubular invasive breast cancer.

The informative value of conventional x-ray film and computed tomography was analysed on the basis of findings in 214 patients having 9 primary and 189 secondary malignant tumours as well as 16 benign bone tumours. In 44% of the benign bone tumours CT yielded decisive additional information in so far as it became possible to determine the type of tumour (4) or the paraosseous tumour extension (3), respectively. The tumour status of the primary malignant tumours was determined throughout via x-ray film, whereas intraosseous and extraosseous extension of the tumorous process was covered much better by computed tomography. CT did not yield additional information in 28% of the secondary malignant bone tumours, whereas 33% of the osseous destructions--depending on the size and localisation--could be identified only via computed tomography. Decisive additional information was gained via CT in 39% of the patients mainly in respect of intraspinal or endocranial tumour extension.