Christine W. Heron

Intravenous urography with low-osmolality contrast agents: Theoretical considerations and clinical findings

There are theoretical reasons for expecting some aspects of image quality in intravenous urography to be modified when low-osmolality, rather than conventional, contrast agents are used. The clinical findings in urography using two of these, the non-ionic agents iohexol (Omnipaque 350, Nyegaard) and iopamidol (Niopam 370, Bracco/Merck), are compared with those using sodium iothalamate (Conray 420, May & Baker Ltd), and are discussed against this theoretical background. The best nephrogram obtained with the new agents often occurred later than with the conventional agent, but quantitative differences in its density were explicable on a total iodine dose basis. The pyelographic density obtained with the new agents was significantly greater than with the conventional agent without any evidence, when abdominal compression was used, of the predicted associated poor distension of the collecting system.

The value of CT in the diagnosis of recurrent carcinoma of the cervix

The results of computed tomography (CT) and other imaging techniques performed on 70 patients who were investigated for suspected recurrent carcinoma of the cervix are reported. Recurrent disease was present in 39 patients. In 29, there was local recurrence with or without distant metastases and there was distant recurrence only in 10. Computed tomography correctly assessed the presence of local recurrent disease in 85% of patients. Six equivocal, two false positive and two false negative CT examinations in the assessment of local recurrence were due either to difficulty in differentiating recurrent disease from changes following radiotherapy, or to the failure of CT to detect small areas of local recurrent disease. Ultrasound and lymphangiography each detected recurrence in one patient which was missed by CT, but this was the most reliable technique for the detection of both local and distant recurrent disease.

Magnetic resonance imaging in recurrent carcinoma of the cervix

Twenty patients with suspected recurrent cervical carcinoma were evaluated with computed tomography (CT) and high-field magnetic resonance imaging (MRI). Histological verification of the imaging findings were available in all cases. Computed tomography and MRI were equally effective in making the diagnosis of disease recurrence. The extent of vaginal recurrence and involvement of pelvic floor muscles was better shown on MRI than on CT.

Radiographic features in patients with pulmonary manifestations of the acquired immune deficiency syndrome

The radiographic findings in 14 episodes of pulmonary pathology, occurring in 13 patients with the acquired immune deficiency syndrome (AIDS) are described. The patients presented over a 15-month period. All were homosexual men with serum antibodies to human T-cell lymphotrophic virus III. Pneumocystis carinii pneumonia was the most common manifestation, occurring in seven of the 14 episodes. Radiographic appearances in five of these were classical, with bilateral perihilar ground-glass shadowing initially. In one the appearances were complicated by a superadded bacterial infection and in one the chest radiograph was normal. Bacterial infections occurred in five of the 14 episodes and, when present, showed the characteristic radiographic appearances of the causative organism. Three patients had widespread Kaposis sarcoma. Bronchoscopy, broncho-alveolar lavage and transbronchial biopsy were often necessary to identify the causative agent. They were also indicated when atypical radiographic appearances occurred during the course of treatment as additional organisms could be found. The radiographic appearances of the conditions reported are felt to be sufficiently characteristic for the radiologist to play a useful role in suggesting the diagnosis and in monitoring the progression of disease in these patients.

The value of thoracic computed tomography in the detection of recurrent Hodgkin's disease

Fifty chest radiographs and concurrent thoracic computed tomography (CT) scans obtained in a total of 44 patients with 50 separate episodes of suspected recurrent Hodgkins disease were reviewed. Recurrent disease was present in 18 episodes, involving the mediastinum in 12, the lung parenchyma in five and both mediastinum and lung parenchyma in one. In four episodes, mediastinal recurrence was demonstrated on both the chest radiograph and CT scan. In a further two cases, the chest radiograph appeared normal but CT detected recurrence in the mediastinum. In 20 cases, the mediastinal appearances on chest radiography were suspicious but not diagnostic of recurrence, usually because of previous radiotherapy resulting in residual mediastinal widening. Computed tomography diagnosed recurrent disease which was subsequently proven in seven of these cases. Recurrent disease was suggested by CT in a further case, subsequently shown to be radiation fibrosis. Of the 12 remaining chest radiographs in which the mediastinal assessment was indeterminate, CT was true negative for recurrent disease in 10 cases and was also indeterminate in two. Recurrent disease in the lung parenchyma was demonstrated on the chest radiograph and CT scan on five occasions. There was one incident in which the chest radiograph was normal but CT detected recurrent parenchymal disease. The appearances of the lung parenchyma were indeterminate for recurrent disease on three chest radiographs but CT was helpful in only one case in which radiation change alone was diagnosed. In eight cases the diagnosis of recurrent disease by CT resulted in a decision to initiate treatment. Computed tomography is of value in detecting relapse in patients with suspected recurrent Hodgkins disease when the chest radiograph is inconclusive, and may enable differentiation of radiation change from recurrent disease in the mediastinum.

Computed tomography of the abdomen in advanced seminoma: Response to treatment

Thirty-three patients with advanced seminoma of the testis underwent serial computed tomography (CT) of the abdomen before, during and after chemotherapy. The immediate post-chemotherapy CT examination showed significant regression in 29 patients and complete resolution in the remaining four (mean regression 70%). Continued CT follow-up at 1 and 2 years revealed further regression of residual masses without further treatment. We recommend that in this group of patients follow-up CT is carried out immediately after chemotherapy and at 1 year. Provided a satisfactory response is observed no further CT assessment is required unless there is clinical suspicion of relapse.

Case report: anomalous systemic venous drainage occurring in association with the hypogenetic lung syndrome

A case in which anomalous systemic venous drainage occurred in association with the hypogenetic lung syndrome (scimitar syndrome) is described. The chest radiograph appearances of the anomalous systemic vein mimicked an anomalous pulmonary or scimitar vein. Angiography demonstrated that the patient also had a small anomalous pulmonary vein draining and a systemic artery supplying, the right lung. As the right lung was hypoplastic, all three features of the hypogenetic lung syndrome were present, in addition to partial anomalous systemic venous drainage.

An opportunity not to be missed

A 55-year-old man presented with a 10-day history of breathlessness and productive cough. A chest infection was diagnosed clinically and treated with antibiotics although the chest radiograph was normal.

The appearance of the inferior thyroid veins on computed tomography

Computed tomography (CT) scans of the mediastinum in 80 patients were reviewed retrospectively to determine the nature of small opacities which are identified on contiguous cuts. These structures varied in number from one to five. The pattern of enhancement, appearance on contiguous CT sections and position in the mediastinum led us to believe that these represent inferior thyroid veins. To our knowledge their appearance on CT has not been reported previously.

The role of routine intravenous urography in patients with primary hyperparathyroidism

The plain abdominal radiographs and intravenous urograms of 72 patients with primary hyperparathyroidism were reviewed. Renal tract calcification was detected on plain abdominal radiographs in 27 patients (38%), and intravenous urography revealed no calculi not detected on the plain radiographs. Intravenous urography did, however, show abnormalities not detected on plain abdominal radiographs in 22 patients (37%), but these findings influenced clinical management in only five patients (7%). In these five patients there were indications other than primary hyperparathyroidism for performing an intravenous urogram. Intravenous urography incurs a small risk and should not be performed as a routine investigation in primary hyperparathyroidism.