Search

Objective: Preoperative staging of pancreatic tumors is frequently accomplished through a combined effort of CT and arteriography. For tumor detection and delineation of disease extent CT is utilized routinely, with CT arterial portography (CTAP) being the single most accurate study for the detection liver metastases. Arteriography has remained the "gold" standard for assessing vascular involvement. The purpose of this study was to determine whether CTAP could become the single study of choice for assessing resectability in patients with pancreatic and periampullary tumors with particular emphasis on its accuracy in determining vascular involvement., Materials and Methods: Radiologic studies and medical records were reviewed in 20 patients who had received both CTAP and arteriographic examinations for preoperative assessment of pancreatic and periampullary tumors. These findings were correlated with results from either surgery (12 cases) or percutaneous biopsy and follow-up (8 cases) in 12 nonresectable and 8 resectable tumors., Results: Arteriography and CTAP correctly concurred in 75% of cases (15 of 20); CTAP correctly demonstrated vascular involvement not appreciated on arteriography in 15% (3 of 20) with an overall sensitivity and specificity of 90 and 100%, respectively. Arteriography was superior to CTAP in one patient (5%) with an overall sensitivity and specificity of 70 and 90%, respectively, for predicting vascular involvement by tumor., Conclusion: Our experience suggests that CTAP is more accurate than arteriography for demonstrating tumor involvement of major peripancreatic vessels. Because CTAP, additionally, has a high sensitivity for detecting liver metastases, no further studies may be necessary to determine operability of these patients.

Noninvasive imaging studies, particularly computed tomography (CT), are the first step in evaluation of patients with suspected hepatic trauma. Iatrogenic injury, accounting for up to one-third of cases, may commonly result in hepatic artery pseudoaneurysm formation. We present a case in which a giant hepatic artery pseudoaneurysm was misinterpreted as an intrahepatic hematoma on sequential CT scans due to the failure to employ dynamic contrast-enhanced scan techniques.

Epidermoid tumours are rare lesions within the skull which are usually found in a cerebellopontine angle. In the computed tomography (CT) literature, they have been described as well-defined lesions of low density which seldom show calcification or tissue enhancement. We have recently encountered three intracranial epidermoids, which appeared to exhibit uniform findings on low field strength magnetic resonance (MR) of moderate signal intensity in the T1-weighted images and a bright signal (increased T2) in the T2-weighted sequences. It may be possible to predict accurately the presence of an epidermoid tumour when this particular configuration of findings is present.

Although the hand is highly vascular and subjected to frequent and often repeated trauma, only 52 cases of true aneurysms have been described up to 1982 (Martin and Manktelow, 1982). Of these cases, 60% involved the ulnar artery. These injuries have a distinct tendency to occur in workers who routinely use hammers and screwdrivers, thus it can be considered an occupational disease (Middleton, 1933). A single violent traumatic event is rarely the cause, but rather repeated minor trauma over several months or years appears to be the more common history. A case with arteriographic demonstration of occlusion of the common and proper digital arteries secondary to emboli originating from a traumatic true aneurysm of the ulnar artery is presented.

Intrathoracic extramedullary hematopoiesis is a rare neoplasm that is most often asymptomatic and usually discovered during a screening examination for another problem. We present a case of intrathoracic extramedullary hematopoiesis in a patient with homozygous sickle cell disease with CT and magnetic resonance correlation.

Sirenomelia is a rare birth defect characterized by fusion of the lower extremities into one limb and a wide spectrum of both genitourinary and lower gastrointestinal tract anomalies. We wish to report the occurrence of this syndrome in an infant whose genitourinary and gastrointestinal anomalies are compatible with life.

The ability of magnetic resonance (MR) imaging to potentially distinguish areas of fluid in motion from areas of static fluid would seem to make it possible to differentiate functioning ventriculoperitoneal shunts from non-functioning shunts in hydrocephalic patients. To test this hypothesis, a standard adult ventricular shunt system including tubing and flow control valve was tested and imaged in vitro in a flow phantom on a 1.5 T magnet with flow rates of 0, 22, 1.00, 0.50, and 0.25 ml/min. A flow void sign was present in the flow control valve on mildly and heavily T2-weighted images at all four flow rates and absent when the flow rate was 0 ml/min. In addition, we were able to image a flow void sign in the flow control valve of a patient with a functioning ventricular shunt, as well as to demonstrate absence of the flow void sign in the flow control valve in a patient with an obstructed ventricular shunt. This data suggest that MR imaging of the flow control valve in patients with ventricular shunts could yield valuable information on shunt patency.