Bronchoperitoneal fistula secondary to chronic Klebsiella pneumoniae subphrenic abscess.

We treated a case of bronchoperitoneal fistula secondary to a Klebsiella pneumoniae subphrenic abscess. This fistulous communication and the surgical procedure used to treat it are described.

Right-to-left shunt from systemic venous to pulmonary venous system developing after SVC obstruction.

This report and review of the literature describe a rare form of right-to-left shunt found in patients with superior vena cava (SVC) obstruction. Following SVC obstruction, collateral vessels may develop between the systemic venous system and the pulmonary venous system causing the alveolar space and right heart to be bypassed. Perception of this unusual shunting of blood on enhanced chest CT may help explain clinical symptoms of hypoxia.

Topical contrast-enhanced CT and MR dacryocystography: imaging the lacrimal drainage apparatus of healthy volunteers.

OBJECTIVE: The purpose of this study was to evaluate the feasibility of administering topical contrast material during helical CT dacryocystography and topical saline solution during MR dacryocystography to reveal the lacrimal drainage apparatus. SUBJECTS AND METHODS: Fourteen healthy volunteers underwent helical CT dacryocystography, MR dacryocystography, or both. Eight of the 14 subjects underwent both techniques; three subjects underwent MR dacryocystography, and three subjects underwent CT dacryocystography. Images were evaluated by two radiologists for degree of visualization of components of the lacrimal drainage apparatus. Each volunteer was questioned about the relative discomfort of contrast material and saline solution administration. RESULTS: The lacrimal drainage system was seen on both CT dacryocystography and MR dacryocystography. CT dacryocystography allowed two-dimensional and three-dimensional reconstructions on which adjacent bone anatomy could be seen. The MR dacryocystography two-dimensional reconstructions and maximum intensity projections also showed the drainage apparatus. However, smaller drainage structures were more consistently seen on CT dacryocystography than on MR dacryocystography. Saline solution was more comfortable than contrast material. CONCLUSION: CT dacryocystography and MR dacryocystography reproducibly and non-invasively revealed the lacrimal drainage apparatus and allowed a better physiologic examination than cannulation dacryocystography. MR dacryocystography can be performed without administration of ionizing radiation or contrast material, but this technique cannot show adjacent bone anatomy and less consistently showed the smaller drainage structures than CT dacryocystography.

Intravenous cholangiography with helical CT: comparison with endoscopic retrograde cholangiography.

PURPOSE: To determine whether helical computed tomography (CT) performed during intravenous cholangiography can provide useful images of the biliary tree and to compare this technique with endoscopic retrograde cholangiography (ERC). MATERIALS AND METHODS: Eighteen adult patients with clinically suspected biliary disease who were referred for ERC were first examined with helical CT cholangiography performed 75 minutes after intravenous infusion of 100 mL of 10.3% iodipamide meglumine. RESULTS: Helical CT cholangiography revealed good opacification of the biliary tree in 13 of 14 patients with serum bilirubin levels less than 2 mg/dL (34 mumol/L) and poor opacification in three of four patients with levels greater than 2 mg/dL. In six of seven patients with choledocholithiasis, the diagnosis was made by means of helical CT cholangiography. CONCLUSION: Helical CT cholangiography may be a clinically useful method for visualization of the biliary tree in some patients with suspected biliary disease with normal bilirubin levels and in patients in whom attempts at ERC fail.

Radiation exposure to patients and personnel during interventional ERCP at a teaching institution.

BACKGROUND: This study was designed to determine the radiation dose to patients and personnel during ERCP procedures. METHODS: Phantom studies were performed to compare dosimetry for two image capture systems and to determine the effectiveness of shielding in reducing stray radiation. Radiation techniques and dosimetry were recorded in 72 patients undergoing ERCP. RESULTS: Phantom studies indicated that increasing fluoroscopy voltage from 75 to 96 kV decreased entrance dose by 50%. Image capture by digital radiography decreased radiation exposure by 66%. Shielding decreased stray radiation exposure by 93%. All patients underwent cholangiography (n = 71) and/or pancreatography (n = 53). The mean number of interventional ERCP procedures performed per patient was 1.8 (range, 0 to 6). The mean measured patient entrance dose was 80 mGy (8 R; range, 0.2 to 73 R); however, the calculated mean entrance dose (based on measured intensifying screen doses) may have been as high as 3000 mGy (30 R; range, 0.8 to 300 R). Measured patient exposure increased with fluoroscopy time (r = 0.9) and with the number of interventions performed (r = 0.3). The mean dose to personnel was estimated at 0.04 mR. CONCLUSIONS: The patient radiation dose depended most on fluoroscopy time. The dose may be lowered by minimizing fluoroscopy time, using higher voltage and lower current for fluoroscopy, and using digital radiography for documentation. Personnel were adequately protected.

Spiral CT with ionic and nonionic contrast material: evaluation of patient motion and scan quality.

PURPOSE: To assess the effect of rapidly injected ionic or nonionic contrast material on patient motion and scan quality in spiral computed tomography (CT). MATERIALS AND METHODS: One hundred nine patients were prospectively, randomly chosen to receive ionic or nonionic contrast material. An acrylic rod was attached to the anterior abdomen with tape, which allowed an objective measurement of motion. Abdominal spiral CT was performed after intravenous injection of contrast material at a rate of 0.9 g of iodine per second. Scans were evaluated subjectively and objectively for motion and subjectively for quality. Complete data were available in 98 patients (47 in the ionic and 51 in the nonionic group). RESULTS: The acrylic rod moved an average of 0.44 mm per section in the nonionic group and 0.71 mm per section in the ionic group. Both subjective and objective measurements showed a statistically significant difference in patient motion. Use of nonionic contrast material resulted in less patient motion. Scan quality was better with nonionic contrast material. CONCLUSION: Less patient motion occurs and scan quality improves when spiral CT is performed with nonionic contrast material.

Disseminated histoplasmosis in AIDS: findings on chest radiographs.

OBJECTIVE: Our objective was to determine the findings of disseminated histoplasmosis on chest radiographs of patients with AIDS. MATERIALS AND METHODS: Chest radiographs of 50 AIDS patients with documented extrapulmonary histoplasmosis were analyzed retrospectively. The radiographs were evaluated for the presence of parenchymal opacities, pleural effusions, adenopathy, cavitation, and calcified granulomas and lymph nodes. A modification of the International Labour Office scheme was used to classify parenchymal abnormalities as nodular, linear or irregular, reticulonodular, or air-space opacities. RESULTS: Abnormalities were present on radiographs in 23 patients. Nodular opacities were present in 10 patients and were diffusely distributed in nine patients. Linear or irregular opacities were present in seven patients, with diffuse distribution in four and limited involvement in three. Air-space opacities were present in seven patients; the distribution varied from segmental to diffuse involvement of the lung. Small pleural effusions were present in five patients. Adenopathy and Kerley's B lines were each present in three patients. In 27 patients, the chest radiographs were normal. Four of these patients had clinical or microbiological evidence of lung involvement. CONCLUSION: The chest radiographic findings of disseminated histoplasmosis in AIDS patients are varied and nonspecific. The presence of diffuse nodular or linear/irregular opacities in an AIDS patient, especially one who resides in or has resided in an endemic area, should suggest the possibility of disseminated histoplasmosis. Normal findings on chest radiographs do not exclude disseminated infection or lung involvement.

Objective measurement of motion in patients undergoing spiral CT examinations.

PURPOSE: To develop and evaluate an objective measurement of patient motion during spiral computed tomography (CT). MATERIALS AND METHODS: An acrylic rod was attached along the length of the torso in 109 patients (56 women, 53 men; age range, 21-79 years; mean age, 51 years) who underwent abdominal spiral CT examinations. Subjective evaluation of motion was graded on a five-point scale by two radiologists. Objective measurements of motion were determined by means of computer reconstruction of the rod in three dimensions and calculation of the deviation of the rod from its estimated position in the motionless state with time. RESULTS: Complete data were available in 98 patients. Subjective and objective measurements of patient motion showed a moderately high Spearman correlation coefficient of .49 (P < .001). The correlation between either observer and objective measurements was similar to the correlation between one observer and the other. CONCLUSION: This objective technique for assessing patient motion correlated well with subjective methods and may be useful in evaluating scanning parameters that may affect patient motion and hence scan quality.

Abdominal and pelvic needle aspiration biopsies: can we perform them well when using small needles?

BACKGROUND: The aim of this study was to compare abdominal fine-needle aspirations (FNAs) performed with large (>/=20-gauge) or small (

Phantom for calibration of preoperative imaging modalities in endoluminal stent-graft repair of aortic aneurysms.

PURPOSE: Successful deployment of an endoluminal prosthesis for repair of an abdominal aortic aneurysm (AAA) is critically dependent on accurate preoperative assessment of aneurysm morphology with use of such modalities as contrast aortography (CA), spiral computed tomography (CT), magnetic resonance (MR) imaging, and intravascular ultrasonography (IVUWS). The authors describe a new phantom that could be used both to calibrate these four imaging modalities and to determine which imaging technique(s) is (are) best for preoperative AAA sizing. MATERIALS AND METHODS: A life-sized AAA model was constructed of silicone elastomers with luminal access ports for introduction of contrast media and catheters. Contrast material-filled rings were positioned circumferentially along the length of the model as reference points for dimension measurements. The modalities were compared to each other relative to the actual dimensions of the model, as determined at its construction. RESULTS: In this pilot study, all modalities were relatively similar in their ability to measure the dimensions of the AAA model. Length measurements accounted for most of the interinstitutional and interobserver variability. MR imaging had the least variability. CONCLUSIONS: The authors developed a new phantom that can be imaged successfully with CA, CT, MR imaging, and IVUS in repetitive, reproducible fashion. Structural refinements and future larger scale, statistically significant evaluations of such models should establish this as a useful adjunct in multicenter endoluminal stent-graft trials to allow calibration of imaging modalities and to determine which modality or modalities is (are) best for preoperative AAA sizing.

Measurement of liver volume using spiral CT and the curved line and cubic spline algorithms: reproducibility and interobserver variation.

BACKGROUND: The purpose of this article was to evaluate the accuracy and reproducibility of spiral computed tomography (CT) and the curved line and cubic spline algorithms in measuring liver volume. METHODS: Spiral CT was performed in phantoms, cadaveric liver specimens, and 35 live human subjects (19 healthy volunteers and 16 patients). Images were transferred to a workstation, and volumes were measured by two observers. One observer repeated the measurements at a separate sitting. RESULTS: The correlation between the CT measurement and the gold standard measurement of the cadaveric livers was very strong (r = 0.94). For the live human subjects, the intraobserver and interobserver correlations were extremely high (r = 0.999 and 0.997, respectively). The mean difference in liver volume measurements between the separate observations was 1%. CONCLUSION: The accuracy and reproducibility of this method of assessing liver volume are very high.

Screening for hepatocellular carcinoma in patients with advanced cirrhosis.

OBJECTIVE: Most available data on screening for hepatocellular carcinoma (HCC) in patients with cirrhosis originate from Asia and Europe. These data may not be applicable to patients from the United States because of geographic variation in the underlying etiology and other factors. Our aim was to assess the risk of HCC in U.S. patients with cirrhosis undergoing standardized screening. METHODS: All cirrhotic patients evaluated for liver transplantation at our institution from January 1, 1994-December 31, 1997 were included in this study. The screening strategy included initial screening, which was offered to all patients and consisted of alpha-fetoprotein (AFP), abdominal ultrasound, and computed tomography (CT) scan, and extended screening, which was performed only on transplant-eligible patients and consisted of semiannual AFP and ultrasound. RESULTS: During the study period, 285 patients with cirrhosis were evaluated for transplantation and underwent initial screening. Of these, 166 were eligible for transplantation and underwent extended screening during a median follow-up of 15 months (range 6-42 months). Twenty-seven HCC were found, 22 during initial screening and five during extended screening. The cancer-free proportions of the cohort who underwent extended screening at 1, 2, and 3.5 yr were 98.6% +/- 1.4%, 96.4 +/- 1.8%, and 77.1% +/- 1.7%, respectively (mean +/- SE). Hepatitis C, either alone or in part, was the etiology in 63% of patients with HCC. The sensitivity of CT scan (88%) was significantly higher than AFP >20 ng/ml (62%) and ultrasound (59%) for detecting HCC (p < 0.001). CONCLUSIONS: In patients with established cirrhosis, the risk of detecting HCC is maximal at the baseline screening (7%). Hepatitis C was the most common etiology for cirrhosis in study. In U.S. patients with established cirrhosis, CT scan exhibited higher sensitivity for detecting HCC than ultrasound or AFP.