Yon-Cheong Wong

Dr. Yon-Cheong Wong

orcid

Research Focus & Metrics

Academic Career Length

33Years (1994-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 December 2001 in Radiology
Verified
Journal Article
Closed access
CCChi-Jen Chen
Chi-Jen Chen
RLRong-Kuo Lyu
Rong-Kuo Lyu
SLShih-Tseng Lee
Shih-Tseng Lee
YWYon-Cheong Wong
Yon-Cheong Wong
LWLi-Jen Wang
Li-Jen Wang
To examine whether the different appearances of intramedullary high signal intensity (SI) on T2-weighted MR images in cervical spondylotic myelopathy are related to differences in surgical prognosis. The magnetic resonance (MR) findings and Japanese Orthopedic Association (JOA) score of 64 cervical spondylotic myelopathy patients, who underwent decompression surgery, were evaluated. SIs were classified as type 0 if no intramedullary high SI on T2-weighted MR images was noted, type 1 if a predominantly (>50%) faint and fuzzy border of high SI was noted, or type 2 if a predominantly (>50%) intense and well-defined border of high SI was noted. Postoperative JOA scoring and MR imaging were also performed 6 months after surgery. Recovery ratios were calculated. There were 20 type 0, 23 type 1, and 21 type 2 cases. Statistical analyses showed no significant difference in age, sex, cervical curvature, and preoperative JOA score between the three groups. Statistical analyses of the recovery ratio showed significantly poor prognosis of type 2 compared with type 1 (P < .001) and type 0 (P =.001), but no difference between types 0 and 1 (P = .317). After controlling for factors of age, sex, preoperative JOA score, cervical curvature, and cord compression ratio, analysis of covariance showed the same result. Type 1 intramedullary high SI on T2-weighted MR images indicates a better surgical outcome than does type 2.

1 April 2004 in Radiology
Verified
Journal Article
Closed access
CCChi-Jen Chen
Chi-Jen Chen
HHHui-Ling Hsu
Hui-Ling Hsu
YTYing-Chi Tseng
Ying-Chi Tseng
RLRong-Kuo Lyu
Rong-Kuo Lyu
CCChiung-Mei Chen
Chiung-Mei Chen
LSLai-Chu See
Lai-Chu See
To investigate the sensitivity and specificity of various neutral-position magnetic resonance (MR) imaging findings in the diagnosis of Hirayama flexion myelopathy. The neutral-position cervical MR images of 46 patients and 51 control subjects were evaluated for the following findings: localized lower cervical cord atrophy, asymmetric cord flattening, abnormal cervical curvature, loss of attachment (LOA) between the posterior dural sac and subjacent lamina, and noncompressed intramedullary high signal intensity on T2-weighted MR images. The difference in frequency of these findings between the control and patient groups was examined by means of the chi(2) test. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of these MR imaging findings in the diagnosis Hirayama disease were calculated. Multivariate analysis of these findings was also performed. There was a significant difference in the frequency of these MR imaging findings between the control and patient groups (all comparisons, P

1 July 2000
Verified
Journal Article
Closed access
YWYon-Cheong Wong
Yon-Cheong Wong
LWLi-Jen Wang
Li-Jen Wang
CNChip-Jin Ng
Chip-Jin Ng
ITI-Chuan Tseng
I-Chuan Tseng
LSLai-Chu See
Lai-Chu See
To determine the factors predictive of mortality in patients with unstable pelvic fractures after successful transcatheter arterial embolization. A retrospective study of pelvic fractures between May of 1995 and April of 1998 was performed. Of 507 patients, 17 who were unstable underwent embolization. The success rate of embolization and the mortality rate after successful embolization were reviewed. Predictive factors (contrast medium extravasation, initial blood pressure, Injury Severity Score, timing of external fixation, time to angiography, volume of blood transfusion, rate of blood transfusion) of the final outcome were statistically analyzed. Embolization was 100% effective in stopping pelvic hemorrhage. The mortality of patients treated successfully with embolization was 17.6%. Among the predictive factors analyzed, only the rate of blood transfusion before embolization, 11.3 ± 11.0 units/h (death) versus 3.2 ± 1.9 units/h (survival) showed statistical significance with an odds ratio of 1.62 (95% confidence interval, 1.07–2.46). The success rate of embolization was 100% in stopping arterial hemorrhage of unstable pelvic fractures. The survival rate after successful embolization was 82.4%. Patients who had rapid blood transfusion before embolization had a poor final outcome. The risk of dying increased by 62% for every 1 unit/h increase of transfusion rate.

1 January 2010 in Journal of Urology
Verified
Journal Article
Closed access
LWLi-Jen Wang
Li-Jen Wang
YWYon-Cheong Wong
Yon-Cheong Wong
CHChen-Chih Huang
Chen-Chih Huang
CWCheng-Hsien Wu
Cheng-Hsien Wu
SHSheng-Che Hung
Sheng-Che Hung
HCHuan-Wu Chen
Huan-Wu Chen
It is debatable whether traditionally used excretory urography or the recently introduced multidetector computerized tomography urography is more accurate for diagnosing upper urinary tract transitional cell carcinoma. We compared accuracy measures of both methods for diagnosing upper urinary tract transitional cell carcinoma in adult patients with hematuria. We retrospectively analyzed consecutive adult patients with hematuria undergoing excretory urography and multidetector computerized tomography urography before any surgery, intervention or treatment from April 2004 to December 2006 in our hospital. The presence of upper urinary tract transitional cell carcinoma on excretory urography and multidetector computerized tomography urography was reviewed independently by 2 uroradiologists who were blinded to clinical information and other imaging results. Final diagnosis of upper urinary tract transitional cell carcinoma was confirmed by histological results. Measures of the diagnostic accuracy of excretory urography and multidetector computerized tomography urography for upper urinary tract transitional cell carcinoma were calculated and compared with reference to the final diagnosis. Of 34 men and 26 women with hematuria (mean age 60.73 +/- 12.95 years) 19 (31.7%) had a final diagnosis of 24 upper urinary tract transitional cell carcinomas. The sensitivity, specificity and accuracy of excretory urography were 0.750, 0.860 and 0.849, respectively. In contrast, the sensitivity, specificity and accuracy of multidetector computerized tomography urography were 0.958, 1.000 and 0.996, respectively. Overall the area under the receiver operating characteristic curve for multidetector computerized tomography urography was significantly larger than that for excretory urography (0.978 vs 0.815, p = 0.005). Multidetector computerized tomography urography is more sensitive, specific and accurate than excretory urography in the diagnosis of upper urinary tract transitional cell carcinoma in adult patients with hematuria. Therefore, multidetector computerized tomography urography rather than excretory urography should be the first choice noninvasive imaging modality for diagnosing upper urinary tract transitional cell carcinoma.

2 April 2005 in European Radiology
Verified
Journal Article
Closed access
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LWLi-Jen Wang
Li-Jen Wang
YWYon-Cheong Wong
Yon-Cheong Wong
CCCheng-Keng Chuang
Cheng-Keng Chuang
SCSheng-Hsien Chu
Sheng-Hsien Chu
CCChih-Shou Chen
Chih-Shou Chen
YCYang-Jen Chiang
Yang-Jen Chiang

1 December 2000 in The Journal of Trauma: Injury, Infection, and Critical Care
Verified
Journal Article
Closed access
JFJen-Feng Fang
Jen-Feng Fang
RCRay-Jade Chen
Ray-Jade Chen
YWYon-Cheong Wong
Yon-Cheong Wong
BLBeing-Chuan Lin
Being-Chuan Lin
YHYu-Bau Hsu
Yu-Bau Hsu
MCMiin-Fu Chen
Miin-Fu Chen
Background Pooling of contrast material on computed tomographic (CT) scan represents free extravasation of blood as a result of active bleeding. For patients with blunt hepatic injury, aggressive management such as angiography or celiotomy is usually indicated if this sign is detected. The purposes of this study were to further categorize this CT scan finding and to correlate its characteristics with clinical outcomes. This CT scan classification might be helpful for the selection of appropriate management. Methods During a 42-month period, 276 patients with blunt hepatic injury were treated. Two hundred twelve of them were hemodynamically stable after initial resuscitation and underwent abdominal CT scan examination. Pooling of contrast material was detected on the CT scans of 15 patients. The CT scans and medical records were reviewed. Special attention was paid to the presence, location, and character of the extravasated contrast material. Results The finding of pooling of contrast material on CT scan was categorized into three types according to its location and character. Type I showed extravasation and pooling of contrast material in the peritoneal cavity (six patients). All patients with type I CT scan findings became hemodynamically unstable soon after CT scan examination and required emergent laparotomy. Type II findings showed simultaneous presence of hemoperitoneum and intraparenchymal contrast material pooling (six patients). Four patients with type II CT scan findings required laparotomy for hemostasis. Type III findings showed intraparenchymal contrast material pooling without hemoperitoneum (three patients). All patients with type III CT scan signs remained hemodynamically stable. Conclusion With the use of a high-speed spiral CT scanner, it is possible to predict the necessity of operative management or angiography for patients with blunt hepatic injury before deterioration of hemodynamic status. The presence of pooling of contrast material within the peritoneal cavity indicates active and massive bleeding. Patients with this CT scan finding show rapid deterioration of hemodynamic status. Most of these patients might require emergent surgery. Pooling of contrast material in a ruptured hepatic parenchyma indicates active bleeding. Close monitoring and emergent angiography should be performed. Deterioration of hemodynamic status in these patients usually requires prompt surgical intervention. Intraparenchymal pooling of contrast material with unruptured liver capsule often indicates a self-limited hemorrhage. Patients with this CT scan finding have a high possibility of successful nonoperative treatment.