Biomedical subjects
Publications and source records attributed to J G Im.
We present the CT findings of pulmonary paragonimiasis in a 9-year-old girl. It appeared as a large cystic mass with an air-fluid level and simulated a lung abscess. Communication with a segmental bronchus was demonstrated well on a CT scan obtained after aspiration.
Pulmonary paragonimiasis is a disease caused by a lung fluke. It is endemic to East Asia, but there have been several case reports in North America. Human infestation occurs by ingestion of raw or incompletely cooked freshwater crab or crayfish infected with metacercaria. A retrospective study was performed with 78 patients who lived in South Korea and had chest radiographic findings of pleuropulmonary disease; it was subsequently shown that they had paragonimiasis. The diagnosis was based on positive results of serologic tests for Paragonimus-specific antibody or on the detection of eggs in sputum samples. Radiologic findings from these 78 patients were correlated with the pathologic and radiologic findings from a study of experimentally induced pulmonary paragonimiasis in 21 cats. Findings from the correlative study document that the typical radiologic manifestations of pulmonary paragonimiasis vary with the stage of the disease. Early findings include pneumothorax or hydropneumothorax, focal airspace consolidation, and linear opacities and are caused by the migration of juvenile worms. Later findings include thin-walled cysts, dense masslike consolidation, nodules, or bronchiectasis and are due to worm cysts.
To evaluate findings of active pulmonary tuberculosis on computed tomographic (CT) scans and their sequential changes before and after antituberculous chemotherapy, 29 patients with newly diagnosed pulmonary tuberculosis and 12 patients with recent reactivation were studied prospectively. The diagnosis of active pulmonary tuberculosis was based on positive acid-fast bacilli in sputum (n = 29) and changes on serial radiographs obtained during treatment (n = 12). Twenty-six patients were followed up with CT during treatment for 1-20 months. Lungs from the cadavers of nine other patients, who died of pulmonary tuberculosis, were studied to provide a pathologic basis for diagnosis. At examination with CT, centrilobular lesions (nodules or branching linear structures 2-4 mm in diameter) were most commonly seen (n = 39 [95%]); in the 26 patients with follow-up, most of these lesions disappeared within 5 months after the start of treatment. In 11 of 12 patients with recent reactivation, CT clearly differentiated old fibrotic lesions from new active lesions. Lesions in and around the small airways appear to be the most characteristic CT feature of early active tuberculosis and may be a reliable criterion for disease activity.
The medical records of 336 patients with hepatocellular carcinoma who underwent transcatheter oily chemoembolization (TOCE) performed via the hepatic artery were retrospectively reviewed to ascertain the occurrence of symptomatic pulmonary oil embolism. In 14 patients, more than 20 mL of iodized oil was administered. In six of these 14 patients, respiratory symptoms of cough, hemoptysis, and dyspnea developed 2-5 days after TOCE, and their chest radiographs showed diffuse bilateral pulmonary parenchymal infiltrate. Their arterial partial pressure of oxygen while they breathed room air ranged from 39 to 60 mm Hg during maximum hypoxemia. The symptoms, arterial hypoxemia, and chest radiographic abnormalities completely cleared 10-28 days after TOCE in the five patients who survived. One patient died 10 days after TOCE because of respiratory arrest with a progression of pulmonary infiltrate. Although histopathologic proof is lacking, it is concluded that massive pulmonary embolization of iodized oil was the primary cause of the clinical and radiographic manifestations in these six patients.
OBJECTIVE: The pericardiacophrenic vein is a possible route of collateral circulation when either the superior or the inferior vena cava is obstructed. When the vein is dilated, it can cause an abnormal appearance on chest radiographs. We describe four such patients. MATERIALS AND METHODS: We studied four patients who had abnormalities on conventional chest radiographs due to a grossly dilated pericardiacophrenic vein, confirmed by means of venacavography, CT, or MR imaging. We analyzed the cause of the dilatation and the radiologic findings associated with the dilated pericardiacophrenic vein. RESULTS: The cause of the dilated pericardiacophrenic vein was the membranous obstruction of the inferior vena cava in all four patients. Chest radiographs revealed an undulating vascular shadow (in two cases) or a shadow of several masses (in one case) along the left border of the heart or a poorly defined haziness mimicking a pulmonary parenchymal infiltrate (in one case). A direct communication between the left hepatic vein and the left inferior phrenic vein was seen near their insertion into the inferior vena cava in three cases. Hepatic venous outflow and some of the systemic venous return were directed to this left inferior phrenic-pericardiacophrenic route. CONCLUSION: When obstruction of the inferior vena cava is clinically suspected and the chest radiograph shows abnormalities at the left paracardiac area, a dilated pericardiacophrenic vein due to obstruction in the suprahepatic portion of the inferior vena cava, most likely a membrane, should be considered in the differential diagnosis.
The purpose of this study was to develop an experimental model of pulmonary metastases using VX-2 tumor, and to describe sequential radiologic and pathologic findings with special attention to the interstitial changes around the metastatic nodules. Through ear veins of 25 rabbits, VX-2 tumor cell suspension was injected with 0.8-mm scalp needles. Chest radiographs were taken every other day after tumor injection. The rabbits were sacrificed at scheduled times from 3 to 30 days after tumor injection. The inflated and fixed lungs were examined with visual inspection, low-kV radiography, high resolution CT (HRCT), microradiography of the sliced lung and with histopathologic studies. Hematogeneous pulmonary metastases occurred in 24 of 25 rabbits. In addition to the metastatic nodules, perinodular and peribronchovascular infiltrations were seen on low-kV radiography, HRCT, microradiography and histologic studies.
To evaluate the prognostic implication of ground-glass attenuation at high-resolution computed tomography (HRCT) in assessing response to treatment in fibrosing alveolitis, the authors correlated HRCT findings with the improvement in pulmonary function, as represented by the increase in percentage predicted values on pulmonary function tests after corticosteroid therapy. Nineteen patients underwent HRCT before treatment and pulmonary function testing before and after treatment. The HRCT scans were reviewed by two independent observers. Areas of ground-glass attenuation were quantified subjectively by using a 0%-100% scale with 10% increments. The extent of ground-glass attenuation at HRCT was significantly correlated with improvement in diffusing capacity for carbon monoxide (r = .67, P = .0019), forced vital capacity (r = .71, P = .0007), and forced expiratory volume in 1 second (r = .64, P = .0034) after steroid treatment. These results suggest that ground-glass attenuation at HRCT is a good predictor of response to treatment in fibrosing alveolitis.
Diffuse panbronchiolitis (DPB), which is prevalent in Japan, is known to be rare outside Japan. Although a case of diffuse panbronchiolitis in a second generation Korean was reported in Japan in 1986, no case has been reported in Korea. Recently we found 5 cases of diffuse panbronchiolitis in Korea, two histologically proven and three clinically and radiologically suspected. All 5 cases had the typical respiratory symptoms and signs and a history of chronic sinusitis. In three clinically and radiologically suspected cases, high resolution computed tomography showed the typical findings of DPB and other diseases such as pulmonary emphysema, bronchial asthma, chronic bronchitis and bronchiectasis could be ruled out. More cases of DPB are expected to be found in Korea in the near future.
The CT findings in cases of benign fibrous mesothelioma of the pleura have been described previously, but little attention has been given to a correlation of these findings with the pathologic appearance of the tumors. Accordingly, we analyzed the CT scans in nine proved cases in which pathologic studies were available and compared the pathologic findings with the CT appearance of the tumors. On enhanced CT scans (available in eight patients), the lesions showed significant enhancement in all cases. Pathologic examination showed that the enhancement could be explained by the vascularity of the tumor. Areas of myxoid (n = 7) or cystic (n = 3) degeneration and hemorrhage (n = 3) seen in the pathologic specimens correlated with round or tubular low-attenuation areas on unenhanced and enhanced CT scans. On unenhanced CT scans (n = 3), the tumor density was the same as that of the surrounding musculature. Calcification was seen in one patient. Large lesions showed lobulated borders, but no invasion into the lung parenchyma and chest wall was noted. There was no pleural effusion. Our experience suggests that intense enhancement of the tumors occurs because of the vascularity of the tumors. Areas of low attenuation in the tumors on CT were due to foci of myxoid or cystic degeneration and hemorrhage in the lesion.
Pleuropulmonary paragonimiasis is a disease caused by lung flukes characterized by migration of a juvenile worm in the early stage and by formation of cysts around the worm later on. The purpose of this study was to describe the radiologic manifestations of pleuropulmonary paragonimiasis, with special emphasis on the worm cyst and worm migration track. We retrospectively studied 71 patients who had evidence of pleuropulmonary paragonimiasis on chest radiographs (n = 71) and CT scans (n = 17). The diagnosis was based on the detection of eggs or on positive antibody tests. On chest radiographs, 59 patients (83%) had pulmonary lesions and 43 patients (61%) had pleural lesions. Pulmonary findings included patchy air-space consolidation (n = 37) with or without cystic changes; ring shadows (n = 16); and peripheral linear opacities (n = 29), which were more prominent in patients with pleural effusion. Twelve patients (17%) had bilateral pleural effusions or pneumothoraces. On CT scans, round low-attenuation cystic lesions (5-15 mm), filled either with fluid (n = 5) or gas (n = 5), were characteristically seen within the consolidation. Peripheral linear opacities seen on radiographs were suggestive of worm migration tracks on CT scans. CT may reveal an intracystic worm. Although the findings vary depending on the stage of the disease, findings on chest radiographs are usually typical of paragonimiasis. CT provides more specific information about the worm cyst and the worm migration track.
Endobronchial tuberculosis is present in 10-40% of patients with active pulmonary tuberculosis, and more than 90% of the patients with endobronchial tuberculosis have some degree of bronchial stenosis. The primary treatment for tuberculous bronchial stenosis is antituberculous chemotherapy combined with steroids, but some patients do not respond well, and more aggressive treatment is needed to restore the patency of the involved bronchus. Balloon dilatation of tuberculous bronchial stenosis has been reported to be successful. However, in our experience, balloon dilatation of the stenotic segment has not significantly improved patients' clinical symptoms except in those with very short segmental stenosis. We describe a case of tuberculous bronchial stenosis that was successfully treated with Gianturco self-expanding metallic stents.
We evaluated 23 patients with extrapulmonary tuberculosis (TB) with 67Ga imaging to assess its usefulness in the diagnosis of this condition. We performed computed tomography (CT) in 17 patients to assess CT features of extrapulmonary TB in comparison with findings from 67Ga scans. Nineteen of 23 patients (83%) had positive findings on 67Ga scans. One of five patients with tuberculous mediastinal lymphadenopathy, two patients with cervical lymphadenitis and a patient with renal TB had negative 67Ga scans. It was observed that the detection of previously unrecognized primary foci of TB, without concomitant pulmonary TB, was possible using 67Ga imaging in five patients (22%). The 67Ga scan was relatively sensitive for the localization of extrapulmonary TB. It is suggested that the 67Ga scan could serve as a screening method, when followed by CT and ultrasonography, for the initial detection of occult tuberculous lesions, especially in patients with prolonged fever.
Five patients with congenital broncho-oesophageal fistula confirmed by fistulectomy are presented. Clinical symptoms were chronic or recurrent pulmonary infection, and three patients experienced coughing after swallowing. Pre-operative oesophagograms demonstrated broncho-oesophageal fistulas in all five patients. The fistulous communications were from the lower oesophagus to segmental bronchi of the lower lobe and to the left main bronchus. The fistulas showed smooth marginated serpentine margins with areas of internal trabeculation, and in two patients the fistulas communicated with anomalous bronchi. One patient had anomalous bronchi and subsequently underwent lobectomy which showed microscopic findings of intralobar sequestration. The oesophagus showed localized tenting with its apex to the fistula and mild ipsilateral displacement in four patients.
Four cases of mediastinal tumours involving the intrathoracic vagus and phrenic nerves are presented and their computed tomographic (CT) features are described with particular attention to the intrathoracic course of these nerves. One case of mediastinal plexiform neurofibromatosis appeared as a series of low attenuation masses along the intrathoracic course of the nerves. Three examples of neurilemmomas of the vagus nerve appeared as masses with central low attenuation; one in the retrocaval area, one to the left of the aortic arch, and one in the right paraoesophageal area. Familiarity with the CT anatomy of the vagus and phrenic nerves will greatly assist in the diagnosis of mediastinal tumours.
A 72 year old man with simultaneously occurring squamous cell and neuroendocrine carcinomas in association with cryptogenic fibrosing alveolitis is reported. The tumours were separate and both were in the fibrotic area of the right lower lobe.
To elucidate the nature of the apical opacity that is commonly seen in patients with tuberculosis--usually referred to as an "apical cap" or "apical pleural thickening"--18 patients with upper lobe tuberculosis were studied with high-resolution computed tomography (HRCT). All had a homogeneous apical opacity at least 1 cm thick on chest radiographs. Fifteen of the 18 had a history of pulmonary tuberculosis of more than 5 years duration, and nine showed evidence of ipsilateral pleurisy. HRCT scans at the apex of the thorax in all nine patients scanned at this level showed that extrapleural fat with interspersed vessels accounted for most of the plain radiographic opacity. Scans obtained at a level slightly above visible aerated lung showed extrapleural fat 3-25 mm thick peripherally and atelectatic lung centrally. At more caudal levels, at which both aerated lung and "thickened pleura" were visible on plain radiographs, HRCT showed extrapleural fat (3-20 mm thick), thickened pleura (1-3 mm thick), and atelectatic lung peripherally and areas of emphysematous bullae, bronchiectasis, and atelectatic lung centrally.
The authors prospectively treated 10 consecutive patients with multiloculated empyemas with intracavitary instillation of urokinase via a percutaneous drainage catheter. Urokinase (100,000 IU) in 100 mL of 5% dextrose in water was instilled into the pleural cavity via a percutaneous drainage catheter. After overnight clamping, the catheter was opened and the empyema drained with use of negative suction (20 cm H2O). Intermittent irrigation of the catheter with normal saline was performed to prevent clogging of the catheter. Complete drainage of multiloculated empyemas was accomplished in nine patients by means of intracavitary instillation of urokinase via a single 8-F catheter. One patient showed complete drainage of multiloculated empyema, but recurrent empyema appeared in the site of a previous tube thoracostomy. A total of 100,000-700,000 IU (mean, 400,000 IU) of urokinase were needed for complete drainage in all patients. Plasminogen and fibrin degradation product levels in empyema fluid were determined before instillation of urokinase to demonstrate any fibrinolytic action. No complications occurred.
The purpose of this study is to describe the radiologic manifestations of paraquat-induced pulmonary damage, with special emphasis on the sequential changes seen with this condition. Paraquat is a herbicide that has toxic effects on the lungs, liver, and kidneys. Progressive respiratory failure is a frequent cause of death. We analyzed retrospectively 42 patients with a history of paraquat ingestion and abnormal findings on chest radiographs. Radiographic changes during the first week after ingestion included diffuse consolidation (26/39), pneumomediastinum with or without pneumothorax (15/39), and cardiomegaly with widening of the superior mediastinum (8/39). Small cystic and linear shadows began to appear at the end of the first week and were the preponderant parenchymal abnormality after 2-4 weeks. Focal honeycombing was the major parenchymal abnormality after 4 weeks. High-resolution CT of the lung 9 months after paraquat exposure revealed localized fibrosis containing small cysts. Our study shows that the pulmonary manifestations of paraquat poisoning begin with air-space consolidation, which then leads to end-stage lung.