Pseudoaneurysm in the left ventricular outflow tract after prosthetic aortic valve implantation: evaluation upon multidetector-row computed tomography.

The high accuracy of multidetector-row computed tomography (MDCT) in evaluating prosthetic valve disorders has been confirmed. This, we believe, is the 1st report of the use of MDCT to detect and evaluate left ventricular outflow tract (LVOT) pseudoaneurysms in patients who have undergone aortic valve replacement with prosthetic valves. We used MDCT to scan 21 such patients, 3 of whom had a small pseudoaneurysm in the LVOT. Each pseudoaneurysm projected away from the LVOT and had a narrow neck that was located just below the sewing ring of the prosthetic aortic valve. One pseudoaneurysm was not thrombotic, 1 was partially thrombotic, and 1 was completely thrombotic. One of these had gone undetected earlier on transthoracic echocardiography.We consider MDCT to be superior to echocardiography in the detection of LVOT pseudoaneurysms in patients who have undergone aortic valve replacement with prosthetic valves. We publicize our results in the hope that larger studies will be undertaken in order to investigate the prevalence and clinical implications of our findings.

Mycoplasma pneumonia: clinical and radiographic features in 39 children.

BACKGROUND: The purpose of the present paper was to evaluate the clinical and chest radiographic features of pediatric patients with serologically proven Mycoplasma pneumoniae pneumonia (mycoplasma pneumonia). METHODS: The clinical records and chest radiographs of 39 consecutive patients (19 male, 20 female; age 3-13 years) with serologically positive IgG and IgM mycoplasma pneumonia were reviewed. RESULTS: More than 90% of patients presented with fever and cough and 48% of patients had leukocyte count >10,000/mm(3). A C-reactive protein (CRP) level >0.375 mg/dL was noted in 28 patients (72%). Chest radiographs displayed four different patterns: (i) peribronchial and perivascular interstitial infiltrates (n= 19, 49%); (ii) airspace consolidations (n= 15, 38%); (iii) reticulonodular opacification (n= 3, 8%); and (iv) nodular or mass-like opacification (n= 2, 5%). Bilateral peribronchial perivascular interstitial infiltrations in central and middle lung zones were frequently seen (n= 19, 49%). Other radiological features were bilateral lesions in 51% of patients, pleural effusion in 23%, and hilar lymphadenopathy in 13%. Means of duration for treatment response and hospitalization were 2.5 and 5 days, respectively. CONCLUSION: There are various radiological features of mycoplasma pneumonia in children. Bilateral peribronchial and perivascular interstitial infiltrates were most frequently seen in the present patients.

Electron beam computed tomography evidence of aortic calcification as an independent determinant of coronary artery calcification.

BACKGROUND: Imaging of the aorta has received less attention than imaging of the coronary beds, despite the possible link between aortic and coronary artery disease (CAD). Electron beam computed tomography (EBCT) with 100 ms scanning speed can eliminate pulsation-related motion artifacts. The goals of this study were to evaluate EBCT-detected subclinical atherosclerosis over the whole aorta as in routine abdominal and thoracic CT scans and analyze whether or not the measurements of aortic calcification (AC) can independently predict the presence of coronary artery calcification (CAC), which is a surrogate marker of CAD. METHODS: A consecutive series of 196 adults (male:female, 127:69; mean age, 65.9 +/- 10.5 years) were enrolled for EBCT examinations of the coronary arteries and whole aorta. CAC and AC were calculated by the Agatston method. Major cardiovascular risk factors were also recorded. RESULTS: The greatest amount of AC was seen at the abdominal aorta, followed by the descending aortic arch, thoracic aorta, and ascending aorta. Total AC was significantly correlated with CAC (r = 0.51, p < 0.001). After adjustment for major cardiovascular risk factors of age, gender, diabetes, hypertension, hypercholesterolemia, and family history, the three independent significant determinants of CAC were abdominal AC, thoracic descending AC, and male gender (model r2 = 0.495, p < 0.001). For receiver operating characteristic analysis in predicting the presence of CAC, the threshold of descending AC was 11, with 68.3% sensitivity and 75.0% specificity. The optimal threshold of abdominal AC was 123, with 74.1% sensitivity and 67.9% specificity. CONCLUSION: AC values in different portions of the aorta are independent predictors for the presence of CAC.

Primary malignant melanoma of the esophagus.

Primary malignant melanoma of the esophagus is an uncommon but aggressive tumor with fatal prognosis. We present 2 male patients with a history of dysphagia for a period of time and describe the imaging features of esophagograms and chest computed tomography (CT) scan. Both were proved by endoscopic biopsy. One of them underwent surgical resection. Primary malignant melanomas of the esophagus should be included in the differential diagnosis of bulky and polypoid masses that expand the esophagus without causing obstruction on esophagograms and chest CT scan.

Screening of hospital workers for pulmonary tuberculosis in a medical center in Taiwan.

At a medical center in Taiwan, all workers were examined by chest radiography, to determine the prevalence of pulmonary tuberculosis. The prevalence of tuberculosis among all hospital workers was 0.12%, that among nurses was 0.35%, and that among externally contracted cleaners was 0.57%. All of the Mycobacterium tuberculosis isolates recovered from 2 nurses and from a patient with pulmonary tuberculosis were the Beijing strain, but the strains had different serotypes.

Anatomic proximity of the esophagus to the coronary sinus: implication for catheter ablation within the coronary sinus.

INTRODUCTION: The anatomic proximity between the esophagus and the coronary sinus (CS) might render the esophagus vulnerable to thermal injury during ablation. Therefore, we investigated the anatomic relationship between the esophagus and the CS in patients with atrial fibrillation (AF). METHODS AND RESULTS: Thirty patients (25 males, mean age = 54 +/- 11 years) with drug-refractory paroxysmal AF were included. Sixteen-slice multidetector computed tomography was performed to depict the course of the esophagus and relationship to the CS. The esophagus was in direct contact with the CS in 57% (17/30) of patients (group 1). The mean length of the contact was 6.1 +/- 3.4 mm. In the remaining 13 patients, the esophagus did not come in direct contact with the CS (group 2). The shortest distance between the esophagus and the CS was 4.0 +/- 2.6 mm. The CS diameter (9.4 +/- 1.8 vs 8.5 +/- 2.4 mm, P = 0.15), esophagus width (18.6 +/- 1.6 vs 18.6 +/- 1.7 mm, P = 0.87), anteroposterior diameter of the left atrium (35.9 +/- 3.8 vs 35.0 +/- 3.3 mm, P = 0.58), thickness of the anterior wall of the esophagus (2.9 +/- 0.6 vs 2.9 +/- 0.6 mm, P = 0.97), and shortest distance from the esophagus to the CS ostium (19.3 +/- 5.4 vs 25.0 +/- 6.2 mm, P = 0.02) and to the great cardiac vein (8.5 +/- 5.3 vs 12.1 +/- 6.9 mm, P = 0.10) were compared between the two groups. CONCLUSIONS: In 57% of our patients, the esophagus was in direct contact with the CS, and a significantly shorter distance between the esophagus and the CS ostium was noted in these patients. It is important to prevent esophageal damage when applying energy within the CS.

Percutaneous retrieval of 20 centrally dislodged Port-A catheter fragments.

A total of 20 patients with centrally embolized Port-A catheter fragments underwent the percutaneous retrieval procedures at our hospital. The causes of the dislodgement of these catheters included bad connection between the port and catheter, angulation or distortion at the anastomosis site, severing the catheter during insertion and removal of the catheter, improper catheter position and fatigue of the catheter. Consequently, improper procedure handling by the inexperienced surgeons could be considered as the most frequent cause of embolization. The percutaneous retrieval procedures were successful in all centrally embolized fragments. Of 20 successful retrievals, 16 were performed will loop snare catheters and 4 with Dormia basket retrievers.

Recurrence of pulmonary arteriovenous malformations in a female with hereditary hemorrhagic telangiectasia.

Pulmonary arteriovenous malformations (AVMs) are an uncommon disorder and may cause life-threatening complications if left untreated. The paucity of good longitudinal data on patients with pulmonary AVMs can be a significant challenge clinically. The authors report a case of recurrence of pulmonary AVMs in a young female with hereditary hemorrhagic telangiectasia (HHT) subjected to transcatheter embolotherapy (TCET) in 1995. Recurrence of pulmonary AVMs was suspected because of marked impairment of oxygenation in 1997 and in 2000, while the patient was pregnant, and later confirmed by imaging studies in early 2003. Despite successful embolization of all visible pulmonary AVMs, contrast echocardiography suggested the presence of intrapulmonary shunt. A shunt of 11.4% was measured using a 100% oxygen test. Loss of flow pattern was the immediate change of pulmonary AVMs after TCET shown by chest sonography. A decrease in the size of the pulmonary AVMs was observed 6 weeks later. This case illustrates the clinical relevance of longitudinal monitoring of arterial blood gases in screening for the recurrence of pulmonary AVMs, particularly in patients with HHT, and the roles of chest sonography and contrast echocardiography in monitoring the efficiency of TCET.

Pulmonary Langerhans cell granulomatosis with extrapulmonary involvement.

Pulmonary Langerhans cell granulomatosis is defined as an abnormal Langerhans cells infiltration in the lungs. Multifocal involvement is unusual, however. We report 3 cases of pulmonary Langerhans cell granulomatosis combined with either rib, thyroid or hypothalamus involvement.

Lessons learned from the endovascular treatment of abdominal aortic aneurysm and a preliminary experience of our center.

BACKGROUND: The development of technical approaches for endovascular abdominal aortic aneurysm (AAA) repair during the last decade was briefly reviewed. The role of endovascular AAA repair as a new reliable method of treatment in high-risk patients was evaluated in both the major studies reported and a preliminary result of our center. METHODS: General criteria for the selection and exclusion of high-risk patients were summarized. Six patients (mean age: 72 years) with complex infrarenal AAA underwent endovascular aneurysm repair using the bifurcated stent graft system. Routine follow-up examination included computed tomography performed periodically from the post-operative month up to one year. Patients suspected of endoleak underwent angiography and further endovascular treatment. RESULTS: Successful deployment of the endograft and exclusion of the aneurysm was achieved in all six patients (100%) in our preliminary series. None of our patients required conversion to open aneurysmal repair. Comorbidity was an important factor in the outcome of aneurysm repair in high-risk patients, with cardiovascular disease and chronic obstructive pulmonary disease being the major comorbid conditions. Cardiac events were the most common complications, followed by transient renal failure, wound infection and endoleaks, which were corrected with endovascular treatment. CONCLUSIONS: The long-term results and efficacy of endovascular repair of infrarenal AAA remain to be demonstrated, but the procedure is believed to provide a safe and effective alternative treatment for high-risk patients suffering from AAA.

Usefulness of low-dose spiral CT of the chest in regular follow-up of postoperative non-small cell lung cancer patients: Preliminary report.

OBJECTIVES: There is no consensus for the best postoperative follow-up in patients after complete resection of non-small cell lung cancer. Low-dose computed tomography of chest proves valuable in screening primary lung cancer and may be a useful tool in postoperative surveillance. METHODS: In part 1, 30 patients who underwent surgical resection of non-small cell lung cancer and were at the first (n = 14), second (n = 9), or fifth (n = 7) annual postoperative surveillance were selected chronologically and subjected to chest radiography, low-dose computed tomography, and standard-dose computed tomography to verify the diagnostic accuracy of low-dose computed tomography. In part 2, 43 patients were prospectively enrolled and followed up regularly after complete resection of non-small cell lung cancer. The follow-up protocol included physical examination, sputum cytology, serum carcinoembryonic antigen, chest radiography, and low-dose computed tomography every 3 months in the first 2 years postoperatively until tumor recurrence. RESULTS: In part 1, tumor recurrence was detected by standard-dose computed tomography in 7 cases. Low-dose computed tomography and chest radiography missed 1 and 5 of 7 cases, respectively. In part 2, tumor recurrence was found in 14 cases with 19 metastatic sites. Thirteen of the 14 (92.9%) cases were detected by scheduled visiting and 11 (78.6%) detected by low-dose computed tomography including the 7 without symptoms. Of the 19 recurrent sites found in 14 patients, 11 ones (57.9%) were detected by low-dose computed tomography. CONCLUSIONS: Low-dose computed tomography may be of considerable value in early detection of tumor recurrence in postoperative non-small cell lung cancer patients. Further large prospective studies are needed to verify this issue.

Hepatopulmonary syndrome in a child.

We report a case of congenital biliary atresia and liver cirrhosis who developed hepatopulmonary syndrome thirteen years after Kasai operation. This 15-yea-old girl suffered from hyperbilirubinemia and acholic stool since birth. Congenital biliary atresia was diagnosed at 6 weeks of age and she received Kasai operation when liver cirrhosis was also found during the surgery. Dyspnea and cyanosis insidiously occurred since the age of 13 and she had been admitted to our hospital due to episodes of esophageal varices bleeding where esophageal varices ligation was performed. Serial examinations showed PaO2: 71 mmHg despite of 100% oxygen supplement. Pulmonary catheterization showed multiple arteriovenous shunts and macroaggregated albumin test revealed significant shunting. Contrast-enhanced echocardiogram showed microbubbles in the left heart. Thus, hepatopulmonary syndrome type II was diagnosed. Treatment is a dilemma although liver transplantation with concomitant lung transplantation is a possible choice.

Carbon dioxide angiography in lower limbs: a prospective comparative study with selective iodinated contrast angiography.

This was a prospective comparison of the accuracy and image quality of carbon dioxide digital subtraction angiography (CO2 DSA) and iodinated contrast digital subtraction angiography (ICDSA) in evaluating lower extremity arteries and patient tolerance of the procedures. Selective DSA was performed in 14 Taiwanese patients who were diagnosed with peripheral artery occlusive disease (PAOD). Both contrast materials were administered through mechanical injectors. Post-processing of the image used pixel shifting. Images of vessels were divided into 22 anatomic segments and evaluated by two experienced radiologists. A four-point scale was used to classify diseased vessels. Two interpreters rated the CO2 DSA image against the ICDSA image on a three-point scale. Patient tolerance was assessed from verbal descriptions. Cohen's kappa was used to determine interobserver agreement and descriptive statistics were used to summarize patient experience. Interobserver agreement ranged from fair to excellent, with most being good or excellent. Three patients (21.4%) could not tolerate the whole procedure and nine patients (64.3%) reported discomfort during the CO2 DSA procedure. CO2 DSA image quality was better for the thigh than the distal runoff and pelvic regions. Our results showed that selective CO2 DSA cannot replace ICDSA as a routine diagnostic tool for PAOD because it does not give images of comparative quality.

Percutaneous retrieval of intravascular foreign bodies: experience with 19 cases.

From April 1994 to June 2002, 17 catheter fragments and two guidewires became intravascular foreign bodies during venous catheterization at our hospital. Retrievals of these 19 foreign bodies were performed percutaneously with loop snare techniques (10 cases), Dormia basket retrievers (eight cases) and grasping forceps (one case). The percutaneous retrieval procedures were successful in 18 of 19 cases. A broken Port-A catheter fragment anchored and entrapped in the vascular wall of the right brachiocephalic vein failed to be removed. No complication was noted during or after these percutaneous procedures. Our experience indicates that intravascular foreign bodies can be removed easily, safely, and successfully with currently available percutaneous methods. As a result, major surgical procedures can be avoided if interventional radiologists are familiar with a variety of techniques for the removal of the expanding spectrum of intravascular foreign bodies currently encountered.