MRI of vaginal conditions.

Magnetic resonance imaging (MRI) has become an important part of the assessment of suspected vaginal pathology. This pictorial review demonstrates the MRI features and some of the histopathological findings of a variety of vaginal conditions. These may be congenital (total vaginal agenesis, partial vaginal agenesis, longitudinal vaginal septum, transverse vaginal septum), benign (Bartholin's cyst, diffuse vaginal inflammation, invasive endometriosis, ureterovaginal fistula, post-surgical appearances with the formation of a neovagina and adhesions) or malignant, usually due to extension or recurrence from another pelvic malignancy. In this paper, examples of the above are described and illustrated together with examples of the much rarer primary vaginal malignancies.

Imaging features of pelvic endometriosis.

Although laparoscopy remains the investigation of choice in the diagnosis of endometriosis, imaging does play a significant role in its management. This pictorial review concentrates on the techniques used in the imaging of endometriosis.

MRI appearances of bladder endometriosis.

Endometriosis is characterized by endometrial tissue in ectopic foci outside the uterus. Involvement of the urinary tract is rare, with the bladder being most commonly affected in these cases. Radiologically these lesions, which are usually small, may be difficult to distinguish from intrinsic bladder neoplasia. Four cases of vesical endometriosis are presented with the MRI features that suggest the diagnosis.

Imaging of malignant cervical lymphadenopathy.

Diagnostic imaging is superior to clinical staging in the detection of malignant cervical lymphadenopathy, and thus helps influence therapy and prognosis. The imaging modalities of CT, MRI, US and PET each have their own diagnostic criteria, accuracy and limitations. Newer innovations such as functional imaging, novel MRI contrast agents and FNAC are being appraised with the aim of identifying the micrometastases which are currently radiologically occult.

Asymmetrical hemithorax volume loss due to Wegener's granulomatosis.

Three patients with Wegener's granulomatosis (WG) established by clinical, serological and histological criteria were noted to have marked asymmetrical hemithorax volume loss on thoracic CT. Lung dimensions were analysed from the CT in each case. Evidence of airways disease, parenchymal abnormalities and pleural changes was evaluated on CT, in order to establish the aetiology of the volume loss. Previous pulmonary infection and thoracic intervention were excluded by the clinical data. The three patients had chronic treated thoracic WG for 1-9 years. There was severe asymmetrical pleural disease in one case and parenchymal disease with evidence of fibrotic healing but no evidence of bronchial disease in two cases. Marked asymmetrical volume loss of a hemithorax is a previously unreported finding and should be added to the features of primary chronic thoracic WG. This finding does not require investigation for additional pathology.

Hepatic artery aneurysm.

Hepatic artery aneurysms (HAAs) are rare. A review of the English language literature from 1985 to 1995 for reports of visceral artery aneurysms showed HAA to be the most frequently reported visceral aneurysm during that decade. This increase in incidence relates to the increasing use of percutaneous diagnostic and therapeutic procedures. A second factor is the increased use of diagnostic CT scanning after blunt liver trauma. The purpose of this pictorial review is to illustrate the imaging presentation and radiological management of HAAs.

The presence and significance of lymphadenopathy detected by CT in primary sclerosing cholangitis.

Patients with primary sclerosing cholangitis (PSC) are at increased risk of developing cholangiocarcinoma, which adversely affects their survival especially after orthotopic liver transplantation. All CT scans of patients with PSC referred to the Liver Unit at the Queen Elizabeth Hospital since 1992 were reviewed. The location of any lymph node with a short axis diameter greater than normal was documented. The incidence of lymphadenopathy and cholangiocarcinoma was also documented. 36 scans are reviewed, including eight with cholangiocarcinoma as well as PSC. Abdominal lymphadenopathy was present in 26 cases (66%) and 45 separate lymph node groups were involved in these patients. There were eight cases of cholangiocarcinoma; five were detectable on CT, but only four had significant lymphadenopathy. The remaining three cases of cholangiocarcinoma were not detectable on CT and only one of these had lymphadenopathy. Follow-up of the remaining patients has not demonstrated the development of cholangiocarcinoma. Lymphadenopathy is commonly demonstrated by CT in PSC patients, but does not imply malignancy and should not exclude a patient from undergoing liver transplantation. Conversely cholangiocarcinoma may develop without significant lymphadenopathy.

Case report: ultrasound diagnosis of obstructed Roux loop after cancer of the pancreas or bile duct.

We describe three cases with known pancreatic or bile duct neoplasia treated by surgery who subsequently presented with obstructive jaundice. In all cases ultrasound demonstrated a fluid-filled obstructed Roux loop and a patent biliary-enteric anastomosis. The cause of the obstruction was seen in two cases. Ultrasound is a safe, fast, reliable and non-invasive method in the assessment of these patients.

Duplex Doppler detection of hepatic artery thrombosis following liver transplantation.

Hepatic artery thrombosis is a major cause of morbidity and mortality following liver transplantation. We assessed the value of prospective duplex Doppler ultrasound in detecting hepatic artery thrombosis. One hundred consecutive transplants in 90 patients were studied. Duplex Doppler detected all 10 proven cases of hepatic artery thrombosis. No case of hepatic artery thrombosis was found with a normal duplex study. All arteriograms performed following an abnormal ultrasound demonstrated hepatic arterial occlusion or anastomotic stenosis or a segment of irregular arterial narrowing. We conclude that duplex Doppler is a practical and sensitive method of selecting patients with a presumptive diagnosis of hepatic artery thrombosis for further investigation by angiography.

Ewing sarcoma: MR imaging of chemotherapy-induced changes with histologic correlation.

In a study group of 18 consecutive patients with Ewing sarcoma proved by means of biopsy, the signal intensity characteristics of tumor on magnetic resonance (MR) images were assessed before and after chemotherapy. Sixteen patients underwent MR imaging at 1.5 T before chemotherapy; all 18 patients underwent MR imaging at 1.5 T within 10 days after chemotherapy. Standard spin-echo sequences were used with T1 and T2 weighting in all patients. The primary tumor was visualized in all 16 patients who underwent MR imaging before chemotherapy. Histologic correlation, obtained in 14 patients, showed that areas of high T2-weighted signal intensity on MR images obtained after chemotherapy may represent tumor necrosis, cystic hemorrhagic areas, and fibroblastic repair tissue. In 10 patients (71%), microscopic clusters of viable tumor cells were depicted in areas of both low and high signal intensity after treatment. It is concluded that MR imaging is unreliable for exclusion of active disease, although a pattern of change in signal intensity is qualitative evidence of chemotherapeutic effect.

Non-Hodgkin's lymphoma of the bladder--CT and MRI appearances.

Computed tomography (CT) appearances of two patients with primary bladder non-Hodgkin's lymphoma are presented with magnetic resonance imaging (MRI) correlation in one. The differences between primary and secondary bladder lymphoma with respect to their clinical presentation, course and prognosis are described. Bladder lymphoma is a rare tumour which often presents as a large multilobular submucosal mass, and such an appearance may suggest the diagnosis. Bladder lymphoma, however, cannot be differentiated from the more common transitional cell carcinoma on the basis of CT attenuation values or enhancement patterns, or MRI signal characteristics. The diagnosis must, therefore, be made by histology. Other differential diagnoses and the role of various imaging techniques in the diagnosis and management of bladder lymphoma are considered.

[Comparative evaluation of computerized tomography/magnetic resonance (1.5 T) in the detection of brain metastasis]. / Valutazione comparativa tomografia computerizzata/risonanza magnetica (1,5 T) nell'identificazione delle metastasi cerebrali.

Forty-four patients with small cell carcinoma of the bronchus underwent CT and MR studies of the brain to detect cerebral metastases. All patients were studied with contrast-enhanced CT scans, short (T1-weighted) and long (T2-weighted), spin-echo (SE) and FLASH 90 degrees MR sequences. Gd-DTPA enhanced SE-T1 and FLASH 90 degrees sequences were also obtained. A quantitative comparison of the results was carried out to assess the sensitivity of the different techniques in the detection of brain metastases according to lesion diameter. Metastases were identified in 19/44 patients (43%). All techniques detected the lesions greater than 2 cm; of the metastases less than 2 cm, 63/124 (51%) were detected only by Gd-DTPA SE-T1 and FLASH sequences and 11 more (9%) only by Gd-DTPA SE-T1 scans. All the lesions identified on enhanced CT scans or on T2-weighted images were easily detected by Gd-DTPA scans. CT sensitivity was higher than that of pre-contrast SE-T1 and FLASH studies and only slightly lower than that of T2-weighted images. As for lesions less than 2 cm, Gd-DTPA T1-weighted sequences had the highest detection rate (124 lesions) versus Gd-DTPA FLASH 90 degrees scans (113 lesions) and precontrast T1-weighted scans (45 lesions). When comparing Gd-DTPA SE-T1 and FLASH 90 degrees sequences in the detection of lesions less than 1 cm, we observed that the latter missed 9% of metastases, mainly due to a high rate of magnetic susceptibility artifacts and to lower contrast resolution. Therefore, Gd-DTPA SE-T1 images still remain the most accurate technique in the assessment of cerebral metastases.

Magnetic resonance imaging in extranodal pelvic lymphoma.

A practical MRI strategy for the investigation of pelvic pain in patients with suspected recurrent lymphoma is described and illustrated in five patients. A T1-weighted sagittal examination of the lumbo-sacral spine is used to examine the vertebral bone marrow, spinal canal, exit foraminae and para-aortic lymph nodes. T2-weighted and balanced images are obtained in the axial plane through the pelvis. The balanced images give an excellent demonstration of pelvic lymph nodes and the T2-weighted images are sensitive to the presence of abnormal soft tissue masses and marrow disease.

CT and MR findings in parameningeal leukaemic masses.

This study presents the clinical and imaging findings in seven patients with parameningeal leukaemic masses: four adults with granulocytic sarcoma and three children with soft tissue masses from acute lymphoblastic leukaemia. Computed tomography and magnetic resonance imaging were helpful in detecting these masses and in showing their extent. Magnetic resonance was particularly valuable in demonstrating abnormal bone marrow in the adult patients with granulocytic sarcoma. Computed tomography was valuable in demonstrating leukaemic relapse in the children when examination of CSF or bone marrow showed no evidence of leukaemia.

Mimics of metastases from testicular tumours.

This paper presents 10 patients with a diagnosis of testicular tumour in whom computed tomography (CT) at staging or follow-up demonstrated abnormalities which mimic the appearance of metastatic testicular tumour. The entities mimicking metastases were sarcoidosis, mushroom worker's lung, lymphoma and phaeochromocytoma. Representative examples of these lesions are illustrated and features which may enable the radiologist to differentiate them from metastatic testicular tumour are discussed.

The role of computed tomography in the investigation of recurrent axillary disease in patients with carcinoma of the breast.

Carcinoma of the breast commonly recurs in the axilla. A nodal mass may be palpable and computed tomography (CT) is frequently requested in order to differentiate recurrent tumour from the longer term effects of surgery and radiotherapy. We have reviewed the CT scans of 35 such patients referred consecutively to our CT unit. CT only detected the presence of recurrent tumour in one patient in whom a mass could not be palpated. This patient had a previously irradiated 'wooden' axilla making clinical examination impossible. CT failed to diagnose recurrence in two patients; one with disease in normal sized nodes and the other with axillary vein thrombosis. We conclude that CT of the axilla only appears to be of value when the axilla is impossible to palpate due to previous treatment. The key to the diagnosis of axillary tumour recurrence is careful palpation supplemented by aspiration cytology of any mass. When no mass is evident on clinical examination, CT is unlikely to demonstrate disease.