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Dal Mo Yang

Publications and source records attributed to Dal Mo Yang.

18 recordsLinked to original sources
PubMed2006

MR arthrography in the differential diagnosis of type II superior labral anteroposterior lesion and sublabral recess.

OBJECTIVE: The objective of our study was to assess the utility of five MR arthrographic findings in differentiating type II superior labral anteroposterior (SLAP) lesion from superior sublabral recess. MATERIALS AND METHODS: The MR arthrograms of 55 patients (57 cases) with either type II SLAP lesion (34 cases) or superior sublabral recess (23 cases) who underwent arthroscopic surgery and MR arthrography were retrospectively reviewed. Two independent reviewers searched for the extension, direction, and shape of high signal intensity in the superior labrum on MR arthrograms. In addition, the presence of concomitant anterosuperior labral tear and anteroposterior extension of high signal intensity on axial images was evaluated. The frequencies of these findings in cases of type II SLAP lesion and sublabral recess were evaluated, and the statistical significance of each finding in differentiation of the two groups was assessed. RESULTS: Extension of high signal intensity behind the biceps anchor that extended beneath the labrum on fat-saturated oblique coronal T1-weighted images was found in 33 (97%) of the cases of type II SLAP lesion and 21 (91%) of the cases of sublabral recess. Laterally curved high signal intensity was found in 17 (50%) of the cases of type II SLAP lesion but in only four (17%) of the cases of sublabral recess. Globular or irregular shape of the superior labrum was present in 22 (65%) of the cases of type II SLAP lesion and in 10 (43%) of the cases of sublabral recess. Concomitant anterosuperior labral tear was seen in 14 (41%) of the cases of type II SLAP lesion but in only two (8.7%) of the cases of sublabral recess. Anteroposterior extension of high signal intensity in the superior labrum on fat-saturated axial T1-weighted images was detected in 33 cases of type II SLAP lesion (97%) and in 14 cases of sublabral recess (61%). CONCLUSION: Although the MR arthrographic findings were similar for type II SLAP lesion and sublabral recess, laterally curved high signal intensity on oblique coronal images, concomitant anterosuperior labral tear, and anteroposterior extension of high signal intensity on axial images were helpful findings in the diagnosis of type II SLAP lesion.

Adolescent↗
PubMed2006

Diagnostic values of sonography for assessment of sternal fractures compared with conventional radiography and bone scans.

OBJECTIVE: This study was prospectively undertaken to evaluate the diagnostic value of sonography for detection of sternal fractures. We compared sonographic, conventional radiographic, and bone scan examinations of sternal fractures. METHODS: Fifty consecutive patients (26 male and 24 female; mean age, 45.2 years) were evaluated. Conventional radiography and sonography were performed in all patients, and bone scans were performed in 39 patients. All patients had acute pain and tenderness in anterior midline chest areas. Sonography was performed by 2 musculoskeletal radiologists within 1 to 2 days after admission. Patients underwent conventional radiography at admission and bone scans within 4 to 7 days after admission. Two radiologists reviewed all imaging findings by means of consensus. In addition, sonography was performed in 20 asymptomatic patients in a normal control group. RESULTS: Conventional radiography depicted sternal fractures in 12 of 50 patients. Sternal fractures were detected in 31 of 50 patients on sonography. Fractures on sonography were located in the manubrium (8 cases), upper sternal body (11 cases), mid sternal body (5 cases), and lower sternal body (7 cases). Bone scans showed sternal hot uptakes (accumulations of the radionuclide used) in 18 of 39 patients. In the control group, there were no bony defects or abnormal contours. CONCLUSIONS: We could detect sternal fractures more effectively with sonography than with conventional radiography and bone scans. In addition, sternal fracture locations showed relatively even distributions, and focal fractures in the manubrium were not easily detected on bone scans.

Adolescent↗
PubMed2005

Cystic lesions in the posterosuperior portion of the humeral head on MR arthrography: correlations with gross and histologic findings in cadavers.

OBJECTIVE: The purpose of this study was to describe the appearance of cysts in the posterosuperior portion of the humeral head on MR arthrography and to correlate the MRI findings with the gross and histologic findings in cadavers. CONCLUSION: Cysts in the posterosuperior portion of the humeral head (the bare area) were located in the lateral humeral head just posterior to the greater tuberosity. These cysts were lined with collagen connective tissue and were connected to the joint spaces. We suggest that these pseudocysts in the posterosuperior portion of the humeral head may be a normal variant rather than being an abnormal change or vascular channel.

Adult↗
PubMed2005

Tailgut cyst: MRI evaluation.

OBJECTIVE: The purpose of our study was to evaluate the MRI features of tailgut cysts in five patients. CONCLUSION: Our results suggest that MRI may be useful in the diagnosis of tailgut cyst. A multilocular cystic mass in the presacral space is a characteristic MRI finding of tailgut cyst, which may also be revealed as a cystic mass consisting of a large cyst accompanied by a small peripheral cyst. However, further studies are necessary to establish the usefulness of MRI for evaluating tailgut cysts.

Adult↗
PubMed2005

Torsed appendix testis: gray scale and color Doppler sonographic findings compared with normal appendix testis.

OBJECTIVE: The purpose of this study was to compare the size, shape, echogenicity, and blood flow of the appendix testis on sonography in control subjects and in patients with a torsed appendix testis and to evaluate the usefulness as well as the limitations of these criteria. METHODS: This was a retrospective analysis of 11 lesions with torsed appendix testes and 15 normal appendix testes in 12 children. The following gray scale and color Doppler sonographic features were analyzed: size, shape, echogenicity, and blood flow of the appendix testis. RESULTS: The size of the appendix testis was larger in patients with a torsed appendix testis than in the control subjects (P < .05). A spherical shape of the appendix testis was more common in patients with a torsed appendix testis (P < .05). There was no blood flow within both the torsed and normal appendix testes. However, the frequency of increased periappendiceal blood flow was higher in patients with a torsed appendix testis (P < .05). There was no significant difference in the echogenicity between the torsed and normal appendix testes. CONCLUSIONS: Gray scale and color Doppler sonography may be helpful in the diagnosis of torsion of the appendix testis. A size of 5 mm or larger, spherical shape, and increased periappendiceal blood flow are indicative of a torsed appendix testis.

Adolescent↗
PubMed2003

Liver cirrhosis developed after ketoconazole-induced acute hepatic injury.

We describe a previously healthy woman who developed liver cirrhosis as a sequela of acute hepatic injury that was induced by ketoconazole administration to treat onychomycosis. The initial presentation of the disease was of a typical acute hepatitis, characterized by nausea, anorexia, fatigue, and jaundice that developed during the administration of ketoconazole. Many other causes of hepatitis were absent in the patient. Even though the hepatic injury was gradually resolved for several months after cessation of the drug, the liver function was not completely restored. Six months after the onset of illness, a follow-up abdominal computed tomography and peritoneoscopic liver biopsy were performed. They revealed a marked reduction in the liver volume and a definite cirrhotic change, which persisted for more than 5 years. The case suggests that the administration of ketoconazole can cause liver cirrhosis through acute hepatic injury within a short time under certain circumstances.

Adult↗
PubMed2003

Differential diagnosis of focal epididymal lesions with gray scale sonographic, color Doppler sonographic, and clinical features.

OBJECTIVE: To determine whether focal epididymal lesions can be differentiated on gray scale sonographic, color Doppler sonographic, and clinical features. METHODS: This was a retrospectiveanalysis of 60 focal epididymal lesions in 57 patients. Focal epididymal lesions were classified into 3 groups: nonspecific epididymitis (n = 43), tuberculous epididymitis (n = 10), and benign epididymal masses (n = 7). The following gray scale sonographic, color Doppler sonographic, and clinical features were analyzed: size, location, echogenicity, and heterogeneity of the lesion; hypoechoic or hyperechoic rim presence; hydrocele presence; degree of blood flow in the lesion; patient's age; duration of symptoms; and scrotal tenderness. RESULTS: Lesions were larger in patients with tuberculous epididymitis than in those with either nonspecific epididymitis (P = .007) or benign epididymal masses (P = .0017). The hypoechoic or hyperechoic rim of the lesion was more common in patients with benign epididymal masses than in those with nonspecific epididymitis (P = .002). The degree of blood flow in the lesion was greater in patients with nonspecific epididymitis than in those with either tuberculous epididymitis (P = .0019) or benign epididymal masses (P < .001). The duration of symptoms was shorter in patients with nonspecific epididymitis than in those with either tuberculous epididymitis (P < .001) or benign epididymal masses (P = .0092). The frequency of scrotal tenderness was higher in patients with nonspecific epididymitis than in those with either tuberculous epididymitis (P < .001) or benign epididymal masses (P < .001). CONCLUSIONS: Gray scale sonographic, color Doppler sonographic, and some clinical features may be helpful for differential diagnosis of focal epididymal lesions.

Adult↗
PubMedDate not supplied

Diffuse multinodular infarction of regenerative nodules after massive bleeding from esophageal varices: computed tomography findings.

We report the computed tomography findings in a case of diffuse multinodular infarcted regenerative nodules, which mimicked an infiltrative hepatocellular carcinoma. Computed tomography revealed multiple hypodense lesions in the right hepatic lobe on the arterial phase and progressive enhancement of the peripheral and central portions of the lesions on the portal venous and delayed phases. A pathologic examination indicated that these regenerative nodules were necrotic and surrounded by fibrous tissue.

Carcinoma, Hepatocellular↗
PubMedDate not supplied

Complications of pyogenic hepatic abscess: computed tomography and clinical features.

The purpose of this pictorial essay is to describe the computed tomography (CT) and clinical findings of the various complications of pyogenic hepatic abscesses. The CT and clinical findings of 81 patients who had a confirmed pyogenic hepatic abscess were analyzed retrospectively. Of the 81 patients, 21 cases of various complications from the pyogenic hepatic abscesses were encountered in 17 patients (21%). Two types of complications were observed in 4 patients. These complications included rupture into the pericardial cavity (n = 1), pleuropulmonary complications (n = 11), rupture into the gastrointestinal tract (n = 1), rupture into the peritoneal cavity (n = 3), rupture into the retroperitoneum (n = 1), vascular complications (n = 3), and biliary complications (n = 1). A knowledge of these complications is important for an early diagnosis and appropriate management.

Adult↗
PubMedDate not supplied

Polypoid and papillary cystitis mimicking a large transitional carcinoma in a patient without a history of catheterization: computed tomography and magnetic resonance findings.

The computed tomography and magnetic resonance imaging (MRI) findings of an unusual case of polypoid and papillary cystitis are described, in which the large size of the mass (5 cm) and no history of catheterization favored the diagnosis of transitional carcinoma before surgery. The MRI findings reflected the pathologic features of this cystitis, featuring edematous fibrovascular cores, which appeared as a central branching pattern of high signal intensity on T2-weighted imaging and with enhancement.

Adult↗
PubMedDate not supplied

Anomaly of the portal vein with total ramification of the intrahepatic portal branches from the right umbilical portion: CT features.

PURPOSE: To describe CT findings of portal vein anomaly with total ramification of the intrahepatic portal branches from the right umbilical vein. METHODS: Retrospective analysis was performed in 6 patients with portal vein anomaly with total ramification of the intrahepatic portal branches from the right umbilican vein. We analyzed the position of the umbilical portion of the portal vein and ligamentum teres, and determined the intrahepatic branching pattern of the portal vein. RESULTS: The umbilical portion and ligamentum teres were deviated to the right and seen above the gallbladder fossa in all 6 patients. All major braches of the portal vein ramified from the right umbilical vein in all 6 patients. CONCLUSION: The possibility of this portal vein anomaly should be kept in mind when hepatic resection or partial liver transplantation is required.

Aged↗
PubMedDate not supplied

Computed tomography and sonographic findings of hepatic metastases from gastrointestinal stromal tumors after chemotherapy.

OBJECTIVE: The purpose of this study was to evaluate the computed tomography (CT) and sonographic findings in patients with hepatic metastases from gastrointestinal stromal tumors (GISTs) after STI-571 treatment. METHODS: Computed tomography and sonographic findings of 8 lesions in 6 patients with hepatic metastases from GISTs that were treated with STI-571 were retrospectively analyzed. The change in size, attenuation, and echogenicity of the hepatic metastases from GISTs after STI-571 treatment was evaluated. RESULTS: After treatment with STI-571, the hepatic metastases were decreased in size and the attenuation of the hepatic metastases was homogeneously hypodense on CT. Sonography revealed the hepatic metastases to be centrally cystic with a thin wall (n = 4) or predominantly solid (n = 4) after STI-571 treatment. On color Doppler sonography, no blood flow was identified within the solid portion of the mass. CONCLUSION: After treatment with STI-571, although the hepatic metastases from GISTs exhibit a cystic appearance on CT, they may appear as solid masses on sonography.

Adult↗
PubMedDate not supplied

Retroperitoneal cystic masses: CT, clinical, and pathologic findings and literature review.

Cystic lesions of the retroperitoneum can be classified as either neoplastic or nonneoplastic. Neoplastic lesions include cystic lymphangioma, mucinous cystadenoma, cystic teratoma, cystic mesothelioma, müllerian cyst, epidermoid cyst, tailgut cyst, bronchogenic cyst, cystic change in solid neoplasms, pseudomyxoma retroperitonei, and perianal mucinous carcinoma. Nonneoplastic lesions include pancreatic pseudocyst, nonpancreatic pseudocyst, lymphocele, urinoma, and hematoma. Because the clinical implications of and therapeutic strategies for retroperitoneal cystic masses vary depending on the cause, the ability to noninvasively differentiate between masses is important. Although there is substantial overlap of computed tomographic (CT) findings in various retroperitoneal cysts, some CT features, along with clinical characteristics, may suggest a specific diagnosis. CT may provide important information regarding lesion location, size, and shape; the presence and thickness of a wall; the presence of septa, calcifications, or fat; and involvement of adjacent structures. The most important clinical parameters include patient gender, age, symptoms, and clinical history. Familiarity with the CT and clinical features of various retroperitoneal cystic masses facilitates accurate diagnosis and treatment.

Adult↗
PubMedDate not supplied

Unusual causes of tubo-ovarian abscess: CT and MR imaging findings.

Actinomycosis, tuberculosis, and xanthogranulomatous inflammation are rare but specific causes of tubo-ovarian abscess (TOA). TOAs with these causes are frequently misdiagnosed as ovarian malignancies due to their unusual appearances at computed tomography (CT) and magnetic resonance (MR) imaging. Tubo-ovarian actinomycosis frequently has a predominantly solid appearance. A linear, solid, well-enhancing lesion extending directly from the mass is a characteristic CT and MR imaging finding. Small rim-enhancing lesions in the solid part of the mass are also suggestive of actinomycosis. Tuberculous TOAs usually mimic peritoneal carcinomatosis from ovarian cancers. The granulomatous and fibrotic nature of this infection may be reflected in the CT and MR imaging appearances, which can help in differentiation. TOAs from xanthogranulomatous inflammation demonstrate more nonspecific imaging findings than actinomycotic or tuberculous TOAs, although multiple xanthogranulomas in the mass may be seen on MR images. Knowledge of these characteristics can help one make the correct diagnosis and treat the patients appropriately.

Abscess↗
PubMedDate not supplied

Acute necrotizing encephalopathy in Korean infants and children: imaging findings and diverse clinical outcome.

OBJECTIVE: The purpose of our study was to describe acute necrotizing encephalopathy in Korean infants and children, and we sought to evaluate the prognostic factors. MATERIALS AND METHODS: Acute necrotizing encephalopathy was diagnosed in 14 Korean infants and children. We retrospectively analyzed the neuroimaging findings including the follow-up changes. The clinical course of the disease was graded, and we evaluated prognostic factors including age, serum level of the aminotransferase, hemorrhage, and localized atrophy of the brain. RESULT: This encephalopathy predominantly affected the bilateral thalami (n = 14), pons (n = 12), and midbrain (n = 10) in a symmetrical pattern. Hemorrhage was observed in eight patients (57%). On the follow-up images (n = 12), the brain lesions were reduced in extent for all patients, and generalized atrophy was seen in six patients. Localized tissue loss was observed in five patients and a complete resolution occurred for one patient. All the patients survived and two recovered completely; mild (n = 6) to severe (n = 6) neurological deficits persisted in the remaining 12 patients. The significant prognostic factors identified in this study were the presence of hemorrhage (p = 0.009) and localized atrophy (p = 0.015). CONCLUSION: Acute necrotizing encephalopathy in Korean patients showed the characteristic patterns of the post-infectious encephalopathy as described in the literature. The high survival rate and the relatively favorable clinical course observed for the present study suggest a more diverse spectrum of disease severity than was previously described. The presence of hemorrhage and localized tissue loss on MR images may suggest a poor prognosis.

Brain↗