Clinically suspected pulmonary embolism: is it safe to withhold anticoagulation after a negative spiral CT?

The goal of this study was 3-month clinical outcome in nonanticoagulated patients with clinically suspected acute pulmonary embolism (PE) following a negative spiral CT. During a 6-month period 305 patients underwent spiral CT, of whom only 8 also had a lung scintigraphy. In patients with a final CT report read as not positive for acute PE, all hospital records and answers to a patient questionnaire were analyzed for episodes of venous thrombembolism (VTE). Acute PE was diagnosed at spiral CT in 61 patients (20%). Twenty-six of the remaining 244 patients were excluded from further analysis because of (a) long-term anticoagulation due to symptomatic acute deep venous thrombosis (n = 5), clinically diagnosed acute PE (n = 2), chronic recurrent VTE (n = 4), and cardiac disorders (n = 5); and (b) a normal perfusion scintigram (n = 4) or a negative pulmonary arteriogram (n = 6). Three patients were lost to follow-up. Among the remaining 215 patients only 10 had undergone a negative lower extremity venous study. Sixteen patients (7%) died during the follow-up period, 6 of whom underwent autopsy. Venous thrombembolism was diagnosed in three of the 215 patients (1.4%, 95% confidence limits: 0.5-4.0%), one causing the patient's death. Two patients had advanced thoracic malignancies and the third severe chronic obstructive pulmonary disease (84 years old). A negative spiral CT may be able to exclude clinically significant acute PE with the same accuracy as a normal lung scintigraphy or a negative pulmonary arteriography.

Midterm changes in aortic aneurysm morphology after endovascular repair.

PURPOSE: To study midterm changes in aortic aneurysm morphology after endovascular aneurysm repair. METHODS: Of 94 patients with abdominal aortic aneurysms (AAAs) treated with endografts between November 1993 and August 1998, 84 were available for follow-up. Patients were evaluated preoperatively by spiral computed tomography (CT) and aortography; in follow-up, spiral CT scanning was performed at 1, 3, and 6 months and semiannually thereafter. Measurements of the aneurysm neck diameter, maximum aneurysm diameter, and the distance from the lowermost renal artery to the aortic bifurcation were made preoperatively and in follow-up. RESULTS: Mean follow-up was 17.5 +/- 1.1 months; 56 (67%) patients were followed for 1 year and 28 (33%) for > or = 2 years. There was a median 2-mm increase (interquartile range [IQR] 0 to 3) in neck diameter at 18 months. However, a > or = 3-mm increase was seen in 18 (46%) of 39 patients examined at 18 months (median 4 mm, IQR 3 to 4, p = 0.0001). The maximum AAA diameter decreased by 9 mm (IQR 4 to 16, p = 0.0003) at 24 months, but after 18 months, no further interval decrease was seen. Aneurysms with a persistent endoleak showed either increasing or unchanged AAA diameters. There was no change in the renal artery to bifurcation distance. CONCLUSIONS: The infrarenal aortic neck appears to dilate after AAA endografting, but only in a subset of patients. Shrinkage of aneurysms after successful stent-grafting seems to stop after 18 months, implying that the only indication of late failure in the absence of endoleak might be aneurysm enlargement. Graft-related endoleaks are often associated with an increase in aneurysm diameter.

Power Doppler ultrasonography: alternative to computed tomography in abdominal trauma patients.

The aim of this study was to determine if power Doppler ultrasonography, contrast enhanced when necessary, can be used as an alternative to computed tomography in the diagnosis of trauma-related organ rupture or hematoma. Fifteen patients who had sustained abdominal trauma but who had normal results on B-mode scans were included in the study. Twenty organs (13 livers and 7 spleens) were examined with both contrast-enhanced computed tomography and power Doppler ultrasonography in a blinded fashion. Ultrasonographic contrast was used in five patients. Lack of contrast enhancement (computed tomography) or lack of color in power color Doppler ultrasonography in all or part of the organ was taken as a sign of rupture or hematoma. Five ruptures were detected with both modalities (two hepatic and three splenic). Thus, ultrasonography showed no false-positive or false-negative studies when compared to the computed tomographic results. No significant difference was found in the estimated size of the damaged area between the two types of investigation. The study indicates that power color Doppler ultrasonography may be considered an alternative when a computed tomographic scan of a trauma patient is impossible.

Abdominal aortic aneurysm morphology in candidates for endovascular repair evaluated with spiral computed tomography and digital subtraction angiography.

PURPOSE: To analyze the morphology of abdominal aortic aneurysms (AAAs) and to study the usefulness of spiral computed tomography (CT) versus digital subtraction angiography (DSA) in the evaluation of patients for endovascular repair. METHODS: Of 133 AAA patients (120 men, mean age 67 years, range 52 to 84) evaluated preoperatively with CT imaging, 77 endograft candidates (68 men) were also assessed with intra-arterial DSA. Arterial parameters were measured on axial CT scans and angiographic films for comparison. RESULTS: Mean maximum AAA diameter was 58 +/- 11 mm (range 39 to 95). Aneurysmal neck diameter was consistently smaller on DSA than on CT (20.7 +/- 3.6 mm versus 23.0 +/ 3.5 mm, p < 0.0001). The distance from the most distal renal artery to the aortic bifurcation was longer on angiography than on CT (mean difference 10.0 mm, p < 0.0001). There was a positive correlation between the maximum AAA diameter and the AAA length (r = 0.49, p < 0.0001) and an inverse relationship between the neck length and the neck diameter (r = -0.36, p < 0.0001). No correlation was found between the maximum AAA diameter and maximum iliac diameter, angulation, or length. CONCLUSIONS: AAA anatomy varies widely and independently of the aneurysm size. Therefore, the maximum size of the aneurysm is a poor predictor of whether or not an aneurysm is suitable for endovascular repair. The discrepancy between angiographic and axial CT measurements suggests that neither alone is sufficient as a preoperative imaging technique when evaluating a patient for an endovascular graft procedure.

New sonographic imaging observations in focal pancreatitis.

The imaging findings that ultrasonographically differentiate focal acute pancreatitis (FAP) from a malignant lesion of the pancreas are described. Focal acute pancreatitis is ultrasonographically (US) characterized as a hypoechoic, homogeneous, localized, subsegmental, non-expansive and diffusely demarcated lesion located mostly in the head of the pancreas. It could not be visualized using CT. Endoscopic retrograde cholangiopancreatography (ERCP) performed in 13 of the 32 patients, showed chronic pancreatitis. Focal acute pancreatitis disappeared in 1-6 months at US follow-up. The clinical diagnoses were acute pancreatitis in 11 patients, chronic pancreatitis in 12 patients, biliary disease in 5 patients, hepatopathia in 1 patient while the diagnosis was unknown in 2 patients. No patient developed any pancreatic cancer during a median of 85 months of follow-up. In conclusion, the present data indicate that patients with FAP at US, without any focal lesion seen on either CT or ERCP, have a benign pancreatic lesion, which resolves in 1-6 months; thus, such patients probably do not need any further investigation or follow-up at all.

Ultrasonography in gallstone ileus: a diagnostic challenge.

OBJECTIVE: To describe our experience with ultrasound diagnosis of gallstone ileus in six cases, and to assess the impact of our findings in the light of published reports. DESIGN: Open study. SETTING: Teaching hospital, Sweden. SUBJECTS: Six patients with gallstone ileus. INTERVENTION: Abdominal ultrasound examination. MAIN OUTCOME MEASURES--Correlation with plain abdominal films and with findings at laarotomy. RESULTS: In all six cases ultrasound gave a precise diagnosis of gallstone ileus, together with the exact location of the gallstone, whereas plain films usually indicated only intestinal obstruction of unknown cause. There was not mortality and only one postoperative complication, and all patients were alive and well at the time they were last seen. These results compare well with those of other reported series. CONCLUSION: The high morbidity and mortality of gallstone ileus may be reduced if ultrasonography is used in cases of undiagnosed abdominal pain, particularly in elderly patients with protracted symptoms.

Gallstone ileus demonstrated by CT.

OBJECTIVE: The appearance and evolution of gallstone ileus as seen by CT are reported. MATERIALS AND METHODS: CT examination was performed on three patients with unspecific abdominal pain. In one patient sequential investigations were performed over 7 months. RESULTS: In all cases the gallbladder was greatly distorted, contained air, and was in direct continuity with a thickened duodenal wall. The gallstone was detected in the small bowel in all cases. In one patient sequential CT examinations over several months demonstrated the evolution from uncomplicated gallstone disease to cholecystitis and finally to perforation of the gallstone into the duodenal bulb. CONCLUSION: Awareness of the CT findings in gallstone ileus may result in more rapid diagnosis and treatment, which may lead to a decrease in the rather high morbidity and mortality seen in this disease.