Biomedical subjects

C J Yu

Publications and source records attributed to C J Yu.

87 records · Page 5Linked to original sources

PubMed1992

Value of sonography in determining the nature of pleural effusion: analysis of 320 cases.

To assess the value of sonography in determining the nature of pleural effusions, we prospectively analyzed the sonographic findings in 320 patients with pleural effusion of various causes (224 with exudates and 96 with transudates). The nature of the effusions was established on the basis of chemical, bacteriologic, and cytologic examination of pleural fluid; pleural biopsy; and clinical follow-up. All patients had high-frequency, real-time sonography performed by one of three sonographers who had no clinical information concerning the patients. The sonographer evaluated the images for internal echogenicity of the effusion, thickness of the pleura, and associated parenchymal lesions of the lung. The images were also printed out and interpreted a second time by the other two sonographers to reach a consensus. Our results showed that the two types of effusions could be distinguished on the basis of sonographic findings. Transudates were anechoic, whereas an anechoic effusion could be either a transudate or an exudate. Pleural effusions with complex septated, complex nonseptated, or homogeneously echogenic patterns were always exudates (p less than .01). Sonographic findings of thickened pleura and associated parenchymal lesions in the lung also were indicative of an exudate (p less than .01). Homogenous echogenic effusions were due to hemorrhagic effusion or empyema. Sonographic evidence of a pleural nodule was a specific finding in patients with a malignant effusion. We conclude that sonography is useful in determining the nature of pleural effusion.

Adolescent↗

PubMed1992

Diagnostic and therapeutic use of chest sonography: value in critically ill patients.

OBJECTIVE: Portable chest radiography, used for critically ill patients, often fails to depict thoracic disease clearly. Chest sonography allows good characterization of pleural diseases, mediastinal lesions, and pulmonary consolidations, and provides accurate and safe guidance for interventional procedures. Accordingly, we evaluated its usefulness in the diagnosis and management of critically ill patients. SUBJECTS AND METHODS: Sonography was used prospectively to evaluate 41 critically ill patients, when portable chest radiographs were difficult to interpret and failed to explain the clinical findings. An initial diagnosis was made on the basis of clinical and radiologic information. The final diagnosis was confirmed by thoracentesis (n = 15), image-guided aspiration biopsy (n = 7), surgery (n = 3), and clinical follow-up (n = 16). All 41 sonographic examinations were performed by a sonographer who had no knowledge of the initial diagnosis. The sonographic findings were recorded and analyzed. The usefulness of sonography in diagnosis and management was then evaluated according to the following criteria: diagnostic value--(1) made diagnosis, (2) changed diagnosis, (3) additional information, (4) no benefit; and management aid--(1) affected decision, (2) affected decision and guided thoracentesis, (3) affected diagnosis and guided aspiration, (4) no benefit. RESULTS: Chest sonography was helpful in diagnosis in 27 (66%) of 41 patients and in treatment in 37 (90%) of 41 patients. A significant influence on treatment planning occurred in 17 (41%) of 41 patients. A diagnostic aspiration biopsy under sonographic detected sonographically. Thoracentesis were attempted in 25 of 29 patients with pleural effusion and were successful in 24 patients (96%); a minimal pneumothorax developed in one patient (4%). CONCLUSION: Chest sonography is a useful diagnostic tool for critically ill patients with chest diseases. This technique can be particularly helpful when CT is not available or when critically ill patients cannot be moved.

Aortic Aneurysm↗

PubMed1992

Evaluation of the A-60 IgG ELISA serodiagnostic test for tuberculosis in Taiwan.

To assess the applicability of a serologic test of specific IgG antibody for tuberculous infection in the Taiwan population, serum samples obtained from 118 subjects were analyzed by an ELISA test using mycobacterial antigen 60. There were 50 patients with a documented active infection caused by Mycobacterium tuberculosis (39 pulmonary tuberculosis, five pleurisy, three cervical lymphadenitis and three miliary tuberculosis with extrapulmonary involvement). Of these 50 patients, 42 (84%) showed a positive ELISA test (titer > 200 U). Of the 19 patients with inactive pulmonary tuberculosis, seven (37%) had a positive titer. Of the 22 patients with pulmonary disease other than tuberculosis, four (18%) showed a false-positive. In eight patients with autoimmune diseases, only the patient with rheumatoid arthritis had a positive reaction. One of the 19 healthy controls (5.3%) showed a false-positive result. The overall false-positive rate for the nontuberculous group was 12%. Follow-up examinations in 20 patients with active tuberculosis one month after treatment revealed that seven had an elevation in titers (three of them were initially negative and became positive later), five remained high and eight decreased in titers. Further examinations in six patients two months after treatment showed a decrease in titers. We conclude that this ELISA assay of specific IgG antibody is a valuable serologic test for diagnosis of M. tuberculosis infection. It may be useful in areas with a high prevalence of M. tuberculosis infection.

Adolescent↗

PubMed1992

Lobar bronchioloalveolar carcinoma: an ultrasound study.

To assess whether chest ultrasound (US) can be useful in the diagnosis of lobar bronchioloalveolar carcinoma, we retrospectively analyzed the US patterns of eight patients with bronchioloalveolar carcinoma presenting with lobar consolidation. For comparison, 15 patients with lobar consolidation of a benign etiology were also analyzed. We found that the US patterns of lobar bronchioloalveolar carcinoma had a characteristic homogeneous, echogenic pattern. The air-bronchograms and air-alveolograms were scarce when compared to benign consolidation. The sensitivity of using these US criteria in discriminating lobar bronchioloalveolar carcinoma was 75%, and the specificity was 93%. We also assessed the yield of US-guided transthoracic cutting biopsies in the diagnosis of lobar bronchioloalveolar carcinoma. The diagnostic rate of the US-guided cutting biopsy was 100%, which was superior to other diagnostic procedures, such as sputum cytology (37%), fiberoptic bronchoscopy with brushing or biopsy (32%) and trans-thoracic needle aspiration cytology (50%). None of the patients developed complications. We conclude that the distinct US pattern for lobar bronchioloalveolar carcinoma is a helpful diagnostic sign, and the US-guided biopsy is a useful approach in the diagnosis of lobar bronchioloalveolar carcinoma.

Adenocarcinoma, Bronchiolo-Alveolar↗

PubMed1991

Lung abscesses: US examination and US-guided transthoracic aspiration.

Examinations with ultrasound (US) and US-guided transthoracic aspiration were conducted in 35 patients to enable diagnosis of lung abscesses. Thirty-three of the abscesses (94%) were demonstrated at US, while two lesions were not depicted. At US, lung abscesses were depicted as hypoechoic lesions with irregular outer margins and an abscess cavity that was manifested as a hyperechoic ring. Twenty-five abscesses (71%) had local adhesion to parietal pleura (lesion-pleura symphysis). US-guided transthoracic needle aspiration of fluid from the abscess cavity was performed successfully in 31 of 33 patients (94%). A total of 65 pathogens were isolated from 31 aspirates (41 anaerobes and 24 aerobes), not-withstanding the fact that 23 of the patients had been previously treated with antibiotics. Only two of 65 pathogens (3%) could be recovered from blood culture, seven (11%) from sputum culture, and two from bronchoalveolar lavage (3%). Two patients developed minimal pneumothorax. The authors conclude that US examination and US-guided transthoracic aspiration are useful and safe diagnostic methods of collecting specimens to enable accurate diagnosis of lung abscesses.

Adolescent↗

PubMed1991

Evaluation of ultrasonically guided biopsies of mediastinal masses.

Eighty patients with roentgenographic evidence of mediastinal abnormalities were examined with ultrasonography. Fifty-four lesions were malignant, and 26 lesions were benign. The histologic diagnoses were confirmed by ultrasonically guided fine needle aspiration/cutting needle (Tru-Cut) biopsy, surgical specimens, or transbronchial biopsy. There were no unique ultrasonographic features for diagnosis of specific tumors. Ultrasonically guided aspiration biopsies (UGAB) were performed in 44 of the malignant lesions and in 14 of the benign lesions (nine of the noncystic lesions and five of the cystic lesions). Cytologic diagnosis of malignancies was obtained in 34 (77 percent) of these 44 malignancies; however, accurate histologic classifications of malignancies were achieved in only 24 (55 percent). Accurate diagnoses were achieved in only three (33 percent) of the nine noncystic benign lesions. Ultrasonically guided cutting biopsies (UGCB) were performed in 24 malignant and five benign lesions. All attempts yielded satisfactory specimens for histologic diagnosis. Using UGAB and UGCB together, a positive diagnosis was achieved in 89 percent (39/44) of the malignancies, and accurate histologic diagnosis was achieved in 89 percent and 78 percent (7/9) in malignant and benign noncystic lesions, respectively. Correct histologic diagnosis with UGAB alone is lower in thymoma (55 percent [6/11]) and lymphoma (30 percent [3/10]) but higher in lung cancer (67 percent [8/12]) and metastatic cancer (78 percent [7/9]). There were no complications in this series. We conclude that ultrasonography with UGAB has a high diagnostic yield in diagnosing mediastinal tumors, and UGCB is necessary for thymic tumors, lymphoma, and benign lesions.

Adolescent↗

PubMed1991

Ultrasound-guided pleural biopsy with Tru-Cut needle.

We conducted a study of ultrasound (US)-guided pleural biopsy with a Tru-Cut needle and made a comparison with the results of a traditional pleural biopsy with an Abrams needle. A total of 49 patients with unilateral pleural effusion were included in this study. Twenty-four patients underwent a traditional pleural biopsy with an Abrams needle, and 25 patients underwent a US-guided pleural biopsy with a Tru-Cut needle. The age, sex, and underlying diseases in both groups were compatible. The amount of effusion was much less in the Tru-Cut group. In the patients who underwent the US-guided pleural biopsy with a Tru-Cut needle, the diagnostic sensitivity in pleural tuberculosis was 86 percent (6/7) and in pleural neoplasia it was 70 percent (7/10). In the patients who underwent traditional pleural biopsy with an Abrams needle, the diagnostic sensitivity in pleural tuberculosis was 20 percent (2/10) and in pleural neoplasia it was 44 percent (4/9). The result of US-guided pleural biopsy with a Tru-Cut needle was better than that of pleural biopsy with an Abrams needle, especially in pleural tuberculosis. No complication was found in the Tru-Cut group, but breakage and dislodgment of the tip of an Abrams needle occurred in one patient. The higher diagnostic yield in the Tru-Cut group may be attributed to the US guidance that can delineate the focal pleural abnormalities for biopsy. In conclusion, US-guided pleural biopsy by using a Tru-Cut needle was simple, safe, and well tolerated. It was particularly useful for patients with pleural tumor, thickened pleura, small amounts of pleural effusion, or loculated pleural effusion.

Adult↗

PubMed1990

Early prenatal diagnosis of Meckel syndrome--a case report.

Meckel syndrome is a rare autosomal recessive disorder. The triad of the syndrome consists of occipital encephalocele, polycystic kidneys and postaxial polydactyly. At least two of these features are essential for the diagnosis, but other malformations such as microcephaly, cleft palate and ambiguous genitalia may also be present. The condition is considered invariably fatal. This report demonstrates that the prenatal diagnosis can in principle be established by ultrasound examination alone, and as early as 13 weeks' gestation.

Abnormalities, Multiple↗

PubMed1988