External jugular vein thrombosis: CT demonstration

A case of external jugular venous thrombosis secondary to misplacement of central venous catheter is presented. The CT findings included enlargement of the external jugular vein, central thrombosis, and vessel wall enhancement. Computed tomography is an excellent noninvasive modality for the evaluation of suspected venous thrombosis.     

Renal vein thrombosis in patients with nephrotic syndrome: CT diagnosis

A retrospective evaluation of the computed tomography (CT) findings in 50 patients with the nephrotic syndrome was undertaken. In four patients with clinical manifestations of acute renal vein thrombosis (RVT) on initial examination, the diagnosis was confirmed by CT findings. Three patients had left RVT, one had right RVT, and all four had thrombus in the inferior vena cava (IVC) at the level of the renal veins. Of the remaining 46, otherwise asymptomatic patients, one had bilateral RVT, two had left RVT, and five had isolated IVC thrombus. The abnormalities noted on CT scans were widened renal vein(s) containing thrombus, thrombus in the IVC, renal enlargement, thickened Gerota fascia and formation of pericapsular venous collaterals, and an abnormal renal parenchymal enhancement pattern consisting of prolonged corticomedullary discrimination, delayed and/or persistent paraenchymal opacification, and delayed or absent pyelocalyceal visualization.     

Anomalous inferior vena cava with lumbar vein thrombosis: CT diagnosis

A case of thrombosis of the ascending right lumbar vein in a patient with infrahepatic interruption of the inferior vena cava and azygos-hemiazygos continuation is reported and the CT findings are described.     

Septic thrombosis of the portal vein: CT and clinical observations

The CT and clinical findings were reviewed in seven patients with septic thrombosis of the portal vein (STPV). Of the seven patients, five had associated pyogenic liver abscesses. Five of seven patients presented de novo with STPV without a clinically obvious extrahepatic source of intraabdominal infection. All seven patients were successfully managed nonsurgically with intravenous antibiotics and in two patients percutaneous drainage of hepatic abscesses. Serial follow-up examinations in five patients demonstrated complete resolution of portal venous thrombus in three patients and progression to cavernous transformation in two. When diagnosed early by CT or sonography, STVP may have a more benign clinical course following appropriate antibiotic therapy.     

Portal and hepatic vein thrombosis in liver abscess: CT findings

OBJECTIVE: Our aim is to describe imaging findings of portal and hepatic vein thrombosis in pyogenic liver abscess on contrast-enhanced MDCT and to determine the incidence and evolving patterns on follow-up imaging. METHODS: Over a 5-year period, 67 patients with liver abscess underwent single-phase (n=30) or triphasic (n=37) contrast-enhanced CT. Images were reviewed for the presence of portal vein (PV) or hepatic vein (HV) thrombosis, regional parenchymal attenuation, and changes on follow-up CT. RESULTS: Venous thrombosis was seen in 28/67 patients (42%), involving PV in 16/67 (24%) and HV vein in 15/67 (22%); 3/67 (4%) had both PV and HV thrombosis. Thrombosis was seen as non-enhancing linear structures without expanding the lumen in all cases. Regional parenchymal attenuation during the portal-phase was hyperattenuating (10/16, 63%) or isoattenuating (6/16, 38%) in PV thrombosis, and mostly hypoattenuating (13/15, 87%) in HV thrombosis (P<.001). Of 27 patients with follow-up contrast-enhanced CT, venous thrombosis resolved in 10/27 (37%) within 6 months and persisted in 17/27 (63%) for 3-38 months, including 13 PV thrombosis and 4 HV thrombosis. Interval parenchymal atrophy was seen only in four all with persistent PV thrombosis. CONCLUSIONS: Both PV and HV thrombosis frequently occurs in liver abscess and is seen as non-enhancing linear structures without expanding the lumen on contrast-enhanced CT. Regional attenuation changes in hepatic vein thrombosis were often hypoattenuating whereas none with portal vein thrombosis showed hypoattenuation.     

CT diagnosis of renal vein thrombosis in nephrotic syndrome

Forty-seven patients with nephrotic syndrome were prospectively studied for renal vein (RVT) and inferior vena caval (IVCT) thrombosis with dynamic CT. Renal venography and inferior vena cavography was performed on the 12 patients with and on 5 of the patients without CT evidence of thrombosis. Dynamic CT revealed thrombi in 12 of 47 (26%) of the cases (RVT in 8, IVCT in 5); all were confirmed by venography. In one of the cases with RVT, a thrombus in a superior branch of the left renal vein was revealed by venography but not by CT. Venography was normal in all five patients evaluated with normal dynamic CT. We believe that dynamic CT can be used to effectively examine patients with suspected RVT.     

Diagnosis of deep vein thrombosis using multi-detector helical CT

PURPOSE: To evaluate the usefulness of multi-detector helical CT (MDHCT) with contrast medium in the diagnosis of deep vein thrombosis (DVT). Materials and Methods: The bilateral veins of the dorsal pedis in 45 patients (12 men, 33 women; average age, 64 years) under clinical suspicion of DVT were first punctured using 22-G needles. Then CT scanning from the level of the foot to the inferior vena cava was started 20 sec after the initial injection of 200 mL of dilute contrast medium (50 mL nonionic iodinated contrast medium of 300 mgI/mL and 150 mL saline) at a rate of 5 mL/sec. RESULTS: Two patients were excluded because of unsuccessful venous puncture. The average scanning time in 43 patients was 38.5 +/- 7.9 seconds. Images of veins from the foot to the inferior vena cava were clearly demonstrated in each case. MDHCT showed DVT in 32 cases and patent deep vein in 11 cases. Simultaneous venography of the lower extremity in 18 patients clearly visualized DVT at the same level detected by contrast MDHCT. CONCLUSION: MDHCT for the diangosis of DVT has the advantages of wider scanning range, shorter scanning time, and finer Z-axis resolution than the other diagnostic modalities.     

Variations of the basal vein: identification using three-dimensional CT angiography

BACKGROUND AND PURPOSE: The basal vein of Rosenthal (BVR) presents with many variations because of its origin in the secondary longitudinal anastomoses between embryonic veins. The variations were evaluated by 3D CT angiography imaging. METHODS: Three-dimensional CT angiograms in the axial stereoscopic view and other directions constructed by the voxel transmission method and maximum intensity projection (MIP) images were obtained in 500 sides of 250 patients. RESULTS: The BVR flowed into the great vein of Galen in 87.8%, but the anastomoses between the first and second segments were not confirmed in 36.9% of this type. The first segments with hypoplastic or aplastic anastomoses flowed into the cavernous sinus or the sphenoparietal sinus. Therefore, typical BVRs with these anastomoses accounted only for 55.4% of all sides. More than one fourth of the typical type also entered the anterior veins such as the cavernous sinus. Drainage was to the lateral mesencephalic vein in 5.6%, peduncular vein in 1.6%, and lateral or medial tentorial sinus in 5.0%. CONCLUSION: Variations of the BVR can be classified on the basis of the five drainage pathways formed during the early embryonic stage. Three-dimensional CT angiography can show the stereoscopic anatomy and the main drainage routes, but not hypoplastic veins, which are only visible on MIP images.     

CT findings in acute thrombosis of superior mesenteric vein aneurysm

The CT findings in a case of surgically proven thrombosed aneurysm of the superior mesenteric vein are described. The location of the aneurysm and recognition of the CT features of venous thrombosis may allow preoperative diagnosis.     

Pulsed Doppler duplex sonography and CT of portal vein thrombosis

Five patients with partial or complete portal vein thrombosis were examined by both computed tomography (CT) and pulsed Doppler duplex scanning. Duplex scanning correctly identified portal vein thrombosis in all five. Duplex sonography may be the preferred technique to detect and follow portal vein thrombosis because of lower cost, lack of need for intravenous contrast material, and easier availability for multiple follow-up examinations.     

Gonadal vein thrombosis in patients with acute gastrointestinal inflammation: diagnosis with CT

During a 31-month period, evidence of gonadal vein thrombosis (GVT) was demonstrated by computed tomography (CT) in seven patients who had a broad spectrum of acute gastrointestinal inflammatory lesions, including diverticulitis, ulcerative colitis, Crohn disease, appendicitis with abscess, and perforated appendix with pseudomembranous colitis. All patients had lower abdominal pain, tenderness, fever, and leukocytosis. CT demonstrated thrombus through the length of the gonadal vein in each patient; the entire lumen of the vein was filled. No symptoms relating to GVT were present. GVT may resolve with treatment of the underlying enteric disease alone, and anticoagulant therapy may not be necessary.     

Chronic-stage deep vein thrombosis of the lower extremities: indirect CT venographic findings

OBJECTIVE: To describe the computed tomographic (CT) findings of chronic deep vein thrombosis (DVT) and its evolution from acute DVT. METHODS: Fifty-one consecutive patients with 52 legs confirmed as acute DVT by CT venography underwent follow-up computed tomography more than 2 months later. Follow-up CT findings were assessed retrospectively by consensus between 2 radiologists. The frequencies of CT findings were analyzed for affected venous segments: common iliac, external iliac, femoral, popliteal, and calf veins. RESULTS: Twelve legs (23%) were completely normalized on follow-up computed tomography, but 40 legs (77%) showed abnormal findings as follows: luminal obliteration (n = 16), decreased caliber (n = 30), residual thrombi (n = 3), fibrotic bands (n = 28), ipsilateral muscle enlargement (n = 28), ipsilateral subcutaneous edema (n = 11), and superficial collateral vein development (n = 23). The external iliac vein (26/40, 65%) was the most commonly affected site followed in decreasing order by femoral (29/50, 58%), common iliac (9/18, 50%), popliteal (22/47, 47%), and calf veins (9/43, 21%). Trends were observed whereby luminal obliteration affected iliac veins and fibrotic bands affected femoropopliteal veins. CONCLUSIONS: Luminal obliteration, decreased caliber, fibrotic bands, ipsilateral muscle enlargement, and superficial collateral vein development are common CT findings in chronic DVT of the lower extremity.