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Y G Su

Publications and source records attributed to Y G Su.

10 recordsLinked to original sources
PubMed2001

Sonographic features of xanthogranulomatous pyelonephritis.

PURPOSE: The purpose of this study was to describe the various sonographic features of xanthogranulomatous pyelonephritis (XGP). METHODS: We retrospectively reviewed the CT, sonographic, and medical records of patients diagnosed with XGP from January 1981 to December 1998. Twenty-seven patients for whom XGP was histopathologically confirmed were included in the study. There were 12 men and 15 women, with an age range of 21-86 years (mean, 57 years). All patients had undergone sonography of the kidneys. The renal size, shape, and outline were recorded. The presence of perinephric fluid accumulation, of obstructive uropathy, or of internal echoes in the dilated collecting system and the echotexture of the renal parenchyma were documented. RESULTS: We categorized the XGP into 4 groups on the basis of the sonographic features: (1) diffuse hydronephrotic, 12 patients (44%); (2) diffuse parenchymal, 9 patients (33%); (3) diffuse contracted, 4 patients (15%); and (4) segmental or focal, 2 patients (7%). A localized perinephric fluid collection was present in 4 patients (15%). The preoperative sonographic diagnoses were pyonephrosis (n = 14, 52%), renal pelvic tumor with possible associated infection (n = 5, 19%), renal parenchymal mass (n = 2, 7%), hydronephrosis (n = 2, 7%), and chronic pyelonephritis with renal atrophy (n = 4, 15%). XGP was considered a possible diagnosis in only 11 patients (41%). CONCLUSIONS: XGP has no specific sonographic features but is suggested by parenchymal thinning and hydronephrosis, sonographic signs of chronic obstructive uropathy caused by stones; echoes in the dilated collecting system; and a perinephric fluid collection. CT, needle biopsy, or both are recommended to further evaluate and confirm sonographically suspected XGP.

Adult↗
PubMed1993

[Sonographic patterns and pathological correlation of neuroblastoma].

This study prospectively correlated pathological findings with sonographic results in two cases of neuroblastoma, and retrospectively analyzed the sonographic pattern of neuroblastomas encountered in our hospital in past years. Prospectively, among the five pathologically proved neuroblastomas, only two received operation. The removed specimens were scanned by high resolution ultrasound, and selected areas were guided by a needle for pathological correlation. Pathologically, the hyperechoic region represented tumor necrosis, hemorrhage and calcifications, as well as hypercellularity and irregular arrangement of the neurofilaments. The hypoechoic areas showed less cellularity with loose tumor cells. No pseudorosette formation was noted. In the retrospective study, 26 neural crest tumors were collected, but only 14 cases received sonographic examination. The most common sonographic findings were heterogenous mixed pattern (65%) and heterogenous hyperechoic pattern (21%). Eleven cases showed calcifications. Two cases presented with echogenic lobule. Most of the tumors were larger than 8 cm, ill-defined and grew across the midline (73%). Sonography is advantageous for diagnosis of abdominal mass in children and might be helpful in differentiating neuroblastomas from other tumors.

Adolescent↗
PubMed1993

Detection of renal allograft dysfunction with color Doppler flow ultrasound.

Thirty-six color Doppler flow (CDF) ultrasound studies were performed on 28 allograft kidneys to assess the capability of this technique in diagnosing transplant dysfunction through morphology and Doppler spectra. The composite score obtained from ultrasound images showed no statistical significance. Quantitative studies with Pulsatility Index (PI) and Resistive Index (RI) after localization of the arcuate, interlobar, segmental and main renal arteries by CDF revealed significant differences between normal functioning graft kidneys and the group of acute rejection, as well as the group of acute tubular necrosis (ATN) (P < 0.05). No apparent change was demonstrated in patients with chronic rejection. When PI was greater than 1.60 or RI was greater than 0.80, the transplant kidney was more likely to be rejected, though possibility of ATN should be considered. RI was easier to calculate, and correlated better than PI with the serum creatinine level. CDF expedited the Doppler spectrum study.

Adult↗
PubMed1991

[High resolution real-time sonographic evaluation of superficial lesions].

One hundred and thirty-one cases of suspected superficial soft tissue lesions, excluding parotid, thyroid, parathyroid, breast and scrotum, were collected in 7-year-period in Veterans General Hospital-Taichung. High resolution (10MHz transducer) real-time ultrasound was applied as imaging modality. Among them, 46 cases were proved pathologically or clinically. We retrospectively evaluated the sonographic features and divided them into five major patterns. I. Cystic lesion with smooth margin, II. Cystic lesion with blurred margin, III. Solid lesion with smooth margin, IV. Solid lesion with blurred margin, V. Diffuse infiltrative lesion. In addition, gas or calcification in the lesion and the echogenicity were included in the evaluation. Some of the lesions considered to be of vascular origin were evaluated with doppler. Ultrasonography can accurately recognize cystic, solid, or infiltrative lesions. In spite of the fact that most of the findings are non-specific, several lesions do have characteristic sonographic patterns that can easily be diagnosed, especially in conjunction with the anatomical location, ie. Backer's cyst, branchial cyst, lymphangioma, and abscess. Lesions with cystic or hyperechoic solid patterns can be considered as benign, if the margin is smooth. Lesions with hypoechoic solid pattern and blurred margin, however except for abscess, can be considered as malignant. We conclude that high resolution real-time sonography is a good imaging modality for evaluating superficial soft tissue lesions.

Female↗
PubMed1990

[Magnetic resonance imaging of ovarian cystic teratoma].

Two patients with ovarian cystic teratoma were imaged using real-time ultrasound and 1.0-T magnetic resonance imaging (MRI) devices. The ultrasound appearance of cystic teratoma varies with the internal contents. If bone or teeth is present, highly echogenic foci with posterior shadow will be identified. The cysts may contain solid areas, septa and fluid-fluid levels. The dermoid cyst filled with fat showing characteristic echogenic appearance might confused with the pelvic fact tissue. MRI is well suited to the evaluation of pelvic disorders. The T1 and T2 relaxation times in different tissues might present with different signal intensities by changing the pulse sequences. Fat, with its relatively short T1 and long T2 times, appears bright on the T1-weighted images (short TE and TR) and T2-weighted images (long TE and TR). However, old hemorrhage has the MRI characteristics of short T1 and long T2 times as fat. The inversion recovery sequence with short inversion time (STIR) will suppress signal from fat tissue and this is of particular value in differentiating dermoid from hemorrhagic cyst. MRI is quite efficient in cases where ultrasound study is equivocal or difficult in the technique.

Adult↗
PubMedDate not supplied

Evaluation of breast tumors with color Doppler imaging: a comparison with image-directed Doppler ultrasound.

Doppler ultrasound is an adjunct to other imaging modalities in differentiating benign from malignant breast tumors. Two groups of patients with breast nodules were examined using a 10/4.5 MHz (imaging frequency/pulsed Doppler frequency) image-directed Doppler probe and a 7.0/5.0 MHz color Doppler imaging probe, separately. Whenever flow signals were detected within or at the margin of the breast nodule, the lesion was considered to be malignant. In detecting malignant breast tumors, the sensitivity was 77.3% and 94.5%, specificity 83.3% and 40.1%, accuracy 81% and 63.4% for image directed Doppler and color Doppler imaging, respectively. We found color Doppler to be easier and more efficient in detecting the flow signals of neovascularity in breast tumor. Color Doppler exhibits a higher sensitivity in detecting the malignant breast tumors. However, more false-positive diagnoses were made. Color Doppler ultrasound also expedited the examination, and the whole procedure could be shortened from 35 minutes to 8 minutes compared with our previous examination performed by image-directed Doppler ultrasound. Due to its higher sensitivity and saving in examination time, we use color Doppler imaging as a routine procedure when solid lesions are observed in x-ray mammography or sonography, as a supplement to the diagnosis of breast tumors.

Adolescent↗