Medical management of pneumatosis intestinalis in patients undergoing allogeneic blood and marrow transplantation.

Pneumatosis intestinalis (PI) occurs when gastrointestinal (GI) wall disruption, increased wall permeability or necrosis leads to wall infiltration by gas. It is associated with a spectrum of causal factors, including GI disease in allogeneic blood and marrow transplant patients. Traditionally, PI has been managed surgically with high morbidity and mortality. We describe our experience managing allogeneic blood and marrow transplant patients with PI. From January 1998 to May 2008, 320 patients underwent allogeneic blood and marrow transplant of whom 10 were identified with PI. PI diagnosis was established by computed tomography scan (n=7), plain film (n=2) or colonoscopy (n=1). A total of 9 of 10 patients had ongoing GI GvHD or received recent treatment for GI GvHD. Before April 2002, two patients underwent subtotal colectomy with ileostomy (n=1) and sigmoid colectomy with colostomy (n=1). One patient was managed with bowel rest and total parental nutrition (TPN) only. These three patients died 0.4, 1.1 and 3.9 years after PI diagnosis owing to GI GvHD (n=2) and surgical complications (n=1). Seven patients, diagnosed after September 2006, were treated with GI rest, TPN and antibiotics. PI treated with GI rest, TPN and antibiotics will resolve without surgical intervention. AlloBMT-associated PI is often a non-critical finding that does not represent true GI tract ischemia and/or GI tract perforation.

Rituximab in combination with fludarabine chemotherapy in low-grade or follicular lymphoma.

PURPOSE: To evaluate the safety and efficacy of fludarabine plus rituximab in treatment-naive or relapsed patients with low-grade and/or follicular non-Hodgkin's lymphoma. PATIENTS AND METHODS: This was an open-label, single-arm, single-center phase II study enrolling 40 patients. During the first week of the study, patients received two infusions of rituximab 375 mg/m2 administered 4 days apart. Seventy-two hours after the second infusion of rituximab, patients received the first of six cycles of fludarabine chemotherapy (25 mg/m2/d for 5 days on a 28-day cycle). Single infusions of rituximab were administered 72 hours before the second, fourth, and sixth cycles of fludarabine, and two infusions of rituximab were given 4 weeks after the last cycle of fludarabine. Treatment duration was 26 weeks. RESULTS: An overall response rate of 90% (80% complete response rate) was achieved in the intent-to-treat population. Similar response rates were seen in treatment-naive and previously treated patients. The median duration of response has not been reached at 40+ months. The median follow-up time in this study is 44 months (range, 15 to 66 months). In patients positive for the 14;18 translocation in blood and/or marrow at enrollment, molecular remission was achieved in 88% of cases, with patients remaining negative for up to 4 years to date. Hematologic toxicity was manageable, and except for a 15% incidence of herpes simplex/zoster infections, infectious complications were rare. Nonhematologic toxicities were minimal. CONCLUSION: Rituximab plus fludarabine was well tolerated and associated with an excellent complete response rate, including molecular remissions, in patients with low-grade or follicular lymphoma.

Combined CT venography and pulmonary angiography: how much venous enhancement is routinely obtained?

OBJECTIVE: Combined CT venography and helical pulmonary angiography is a new diagnostic test that permits radiologists to check both the pulmonary arteries for embolism and the deep veins of the abdomen, pelvis, and legs for thrombosis in a single examination. The purpose of this study was to determine the degree of venous enhancement routinely obtained using this combined CT examination. MATERIALS AND METHODS: We identified all patients at a single institution who, during a 29-month period, had symptoms suggestive of pulmonary embolism and who underwent CT venography and helical pulmonary angiography. The examinations were performed after the patients received a rapid (3--5 mL/sec) IV injection of 150 mL of nonionic contrast medium (240 mg I/mL). CT venography of the abdomen, pelvis, and lower extremities was performed as follows: Beginning 3 min after the start of contrast medium infusion for helical CT pulmonary angiography, 1-cm axial images obtained at 5-cm intervals were acquired from an area ranging from the diaphragm to the calves. Patients who had evidence of deep venous thrombosis on CT scans were excluded from further analysis. The venous portions of the remaining 429 examinations were retrospectively reviewed at a CT console or workstation by one of two radiologists, and Hounsfield unit measurements were recorded from the inferior vena cava as well as from the right and left external or internal iliac, common femoral, superficial femoral, and popliteal veins. A single Hounsfield unit measurement was obtained from the center of each vessel using a region of interest that was approximately half the diameter of the vessel. Mean Hounsfield unit measurements were then calculated for these venous stations. RESULTS: Mean Hounsfield unit measurements at the inferior vena cava and at the right and left external or internal iliac veins were 97, 95, and 95 H, respectively. Mean measurements at the common femoral veins were 95 H for both the right and left; the mean measurements at the superficial femoral veins were 91 H for both the right and left, and those at the popliteal veins were 97 H for the right and 94 H for the left. CONCLUSION: CT venography of the abdomen, pelvis, and lower extremities begun 3 min after the start of contrast medium infusion for helical CT pulmonary angiography routinely produced high mean levels of venous enhancement.

Deep venous thrombosis with suspected pulmonary embolism: detection with combined CT venography and pulmonary angiography.

PURPOSE: To determine the frequency and location of deep venous thrombosis at computed tomographic (CT) venography after CT pulmonary angiography in a large series of patients clinically suspected of having pulmonary embolism and to compare the accuracy of CT venography with lower-extremity venous sonography. MATERIALS AND METHODS: Venous phase images were acquired from the diaphragm to the upper calves after completion of CT pulmonary angiography in 650 patients (373 women, 277 men; age range, 18-99 years; mean age, 63 years) to determine the presence and location of deep venous thrombosis. Results of CT venography were compared with those of bilateral lower-extremity venous sonography in 308 patients. RESULTS: A total of 116 patients had pulmonary embolism and/or deep venous thrombosis, including 27 patients with pulmonary embolism alone, 31 patients with deep venous thrombosis alone, and 58 patients with both. Among 89 patients with deep venous thrombosis, thrombosis was bilateral in 26, involved the abdominal or pelvic veins in 11, and was isolated to the abdominal or pelvic veins in four. In patients in whom sonographic correlation was available, CT venography had a sensitivity of 97% and a specificity of 100% for femoropopliteal deep venous thrombosis. CONCLUSION: Combined CT venography and pulmonary angiography can accurately depict the femoropopliteal deep veins, permitting concurrent testing for venous thrombosis and pulmonary embolism. CT venography also defines pelvic or abdominal thrombus, which was seen in 17% of patients with deep venous thrombosis.

Thick-section reformatting of thinly collimated helical CT for reduction of skull base-related artifacts.

OBJECTIVE: Our purpose was to evaluate thick-section reformatted helical CT of the brain base as a technique for reducing skull base-related artifacts and to compare it with conventional CT. MATERIALS AND METHODS: Twenty-three patients with suspected intracranial abnormalities related to the brain base, as determined either by clinical examination or at the time of imaging, were evaluated with contrast-enhanced conventional CT of the brain (5-mm collimation, 140 kVp, 170 mA, 2-sec rotation time) and reformatted helical CT (1-mm collimation, 1.5 pitch, 120 kVp, 220 mA). Helical sections were reformatted to a thickness of 5 mm by a volume-averaging algorithm using a computer workstation. Three observers retrospectively and blindly reviewed the images and qualitatively scored artifacts at the foramen magnum, middle cranial fossa, anterior cranial fossa, interpetrous region, and internal occipital protuberance. Image graininess and observer confidence were also scored. Paired statistical analyses using score differences in each patient were possible. RESULTS: Reformatted helical CT reduced skull base-related artifacts across all five anatomic regions (p < 0.05). The foramen magnum showed the greatest reduction in artifacts and the anterior cranial fossa the least. Image graininess was increased on reformatted CT compared with conventional CT (p < 0.05), but observer confidence remained higher for reformatted CT (p < 0.05). Total additional scan time was 3.15 +/- 0.38 min with 5.3 +/- 1.2 min required for reformatting. CONCLUSION: Reformatted CT significantly decreases skull base-related artifacts in the brain, improving confidence in evaluation of the brain base and adding an average of only 8.45 +/- 1.6 min of scanning and processing time to each examination.

Extra-thoracic findings on the venous phase of combined computed tomographic venography and pulmonary angiography.

A growing consensus is that pulmonary embolism and thrombosis represent different aspects of the same disease, and a single study that accurately defines both pulmonary emboli and deep venous thrombosis would be a desirable examination. The purpose of this pictorial review is to demonstrate the extra-thoracic findings on the venous phase of such a study, which combines computed tomographic venography and pulmonary angiography.

Combined CT venography and pulmonary angiography in suspected thromboembolic disease: diagnostic accuracy for deep venous evaluation.

OBJECTIVE: Combined CT venography and pulmonary angiography is a new diagnostic test that evaluates both pulmonary embolism and deep venous thrombosis (DVT) in a single study. Our purpose was to compare the CT venous findings with lower extremity venous sonography. SUBJECTS AND METHODS: Seventy-one consecutive patients with suspected pulmonary embolism underwent helical CT pulmonary angiography during rapid i.v. infusion of contrast medium. Axial scans at 5-cm intervals from the patient's upper calves to the diaphragm were generated 3.5 min after the beginning of contrast medium injection. CT venous phase images were interpreted prospectively and compared with subsequent bilateral lower extremity venous sonography performed within 12 hr. RESULTS: DVT was revealed by CT venous phase images in 19 patients, 12 of whom also had pulmonary embolism. CT and sonographic findings correlated exactly in the femoropopliteal deep venous system, where most pulmonary emboli originate. CT venous phase images also revealed pelvic extension of DVT in six patients and isolated vena cava thrombus in one patient. CONCLUSION: CT venous phase imaging at the time of CT pulmonary angiography is comparable with venous sonography in the evaluation of femoropopliteal DVT. The iliac veins and vena cava, vessels poorly shown on sonography but sometimes the source of significant pulmonary emboli, are also depicted by CT venography.

Lower extremity deep venous thrombosis in cancer patients: correlation of presenting symptoms with venous sonographic findings.

We sought to determine how rates of sonographically detected deep venous thrombosis correlate with presenting symptoms in cancer patients. We performed venous sonography in 588 cancer patients with clinically suspected lower extremity deep venous thrombosis. Results were correlated with clinical findings. Deep venous thrombosis was diagnosed in 32% of patients with unilateral lower extremity symptoms and in 17% of patients with bilateral symptoms. Patients with unilateral symptoms of pain and swelling, swelling alone, or pain alone had significantly different rates of deep venous thrombosis (47%, 31%, and 16%, respectively). In patients with bilateral leg symptoms, deep venous thrombosis was significantly more likely when symptoms were not bilaterally symmetric.

Carcinosarcoma of the extrahepatic bile ducts: cholangiographic and CT appearance.

A case of histologically proven carcinosarcoma arising in the extrahepatic biliary tree is presented. The tumor appeared on cholangiography and computed tomography as a large expansile intraluminal mass causing biliary obstruction.

MRI of acute cholecystitis: comparison with the normal gallbladder and other entities.

Our purpose was to prospectively compare MRI findings with histopathologic findings in the evaluation of suspected acute cholecystitis. Fourteen patients with clinically suspected acute cholecystitis were entered into the study. MR sequences included T1-weighted fat-suppression and breath-hold spoiled gradient echo (SGE) before and after intravenous gadolinium chelate administration. Percent contrast enhancement (%CE) of the gallbladder wall and gallbladder wall thickness (WT) were measured and liver enhancement patterns determined prospectively on MR images. Correlation was obtained with pathological findings at cholecytectomy in all patients. In a second phase of the study MR images on 10 additional subjects who underwent MR examination for reasons other than hepatobiliary disease were analyzed to determine normal values for %CE and gallbladder wall thickness. Mean %CE was 124.0% in patients with acute cholecystitis (10 patients), 58.0% in patients with chronic cholecystitis (2 patients), and 73.0% in patients with gallbladder malignancy (2 patients). Mean gallbladder WT was 6.1 mm in acute cholecystitis, 4.5 mm in chronic cholecystitis, and 6.0 mm in malignant disease. There was a significant difference in %CE between acute and chronic cholecystitis (p = 0.03); no other significant differences in %CE or WT were observed among the patients with gallbladder disease. Patients without biliary disease had %CE of 37.3% and WT of 2.9 mm, which were both significantly less (p < 0.001) than in patients with acute cholecystitis. Transient enhancement of pericholecystic hepatic parenchyma on immediate postgadolinium SGE images was seen in 7 of 10 patients with acute cholecystitis, and not observed in other patients. Patients with acute cholecystitis had increased %CE and WT on MR images that were significantly greater than normal and %CE that was significantly greater than in patients with chronic cholecystitis. Transient increased pericholecystic hepatic enhancement was observed in 70% of acute cholecystitis patients and in no other patient groups.