Yon-Cheong Wong

Mortality after successful transcatheter arterial embolization in patients with unstable pelvic fractures : Rate of blood transfusion as a predictive factor

BACKGROUND To determine the factors predictive of mortality in patients with unstable pelvic fractures after successful transcatheter arterial embolization. METHODS 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. RESULTS 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). CONCLUSION 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.

Multidetector computerized tomography urography is more accurate than excretory urography for diagnosing transitional cell carcinoma of the upper urinary tract in adults with hematuria.

PURPOSE 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. MATERIALS AND METHODS 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. RESULTS 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). CONCLUSIONS 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.

Usefulness of Multidetector Computed Tomography for the Initial Assessment of Blunt Abdominal Trauma Patients

BackgroundThe prompt detection and accurate localization of abdominal injuries are difficult. Some diagnostic modalities, including laboratory tests, ultrasound, and diagnostic peritoneal lavage (DPL) were used to evaluate patients with blunt abdominal trauma, with various advantages and pitfalls. We aimed to evaluate the risk and benefit of using multidetector computed tomography (MDCT) as an initial assessment tool for proper diagnosis and treatment planning of patients with blunt abdominal trauma.MethodsTwo hundred fifty-two patients with blunt abdominal trauma were prospectively enrolled. Multidetector computed tomography was performed during resuscitation. The risk and benefit of using MDCT in the diagnosis and planning of treatment were analyzed.ResultsThe time required for a MDCT examination averaged 10.2 minutes. Of the studies done, 224 revealed abdominal injuries. Of those, 34 were performed in patients with unstable hemodynamic status without adverse effect. Prompt diagnosis and proper treatment were given according to the MDCT findings. A total of 43 (17.1%) MDCTs showed contrast extravasation. Active bleeding was confirmed in all and treated with transarterial embolization (30) or surgery (13). Another 58 patients sustained bowel, mesenteric, or pancreatic injuries (BMPI) necessitating laparotomy. The sensitivity, specificity, and accuracy of MDCT in identifying patients with active bleeding or BMPI were all 100%.ConclusionsMultidetector computed tomography was useful as a second line initial assessment tool to identify injuries and determine treatment planning in blunt abdominal trauma patients. No increased risk was found if the facility is readily available, the protocol is well designed, and the patient is well prepared.

CT features of genitourinary tuberculosis.

The genitourinary system is the most common site of extrapulmonary tuberculous infection. The diagnosis is difficult and often delayed. In this essay, we illustrate the CT features of the kidneys, ureters, bladder, prostate gland, and seminal vesicles caused by tuberculosis.

Hypoplasia of the internal carotid artery with intercavernous anastomosis.

Abstract We report a symptomatic case of unilateral hypoplasia of the internal carotid artery with an intercavernous anastomosis, a very rare developmental anomaly. The symptoms were caused by occlusion of the proximal middle cerebral artery which possibly related to the haemodynamic stress caused by the anomalous intercavernous anastomosis.

Diagnostic Accuracy of Transitional Cell Carcinoma on Multidetector Computerized Tomography Urography in Patients With Gross Hematuria

PURPOSE We analyzed the diagnostic value of multidetector computerized tomography urography for transitional cell carcinoma in patients with gross hematuria. MATERIALS AND METHODS All consecutive adult patients with gross hematuria who underwent multidetector computerized tomography urography in a 23-month period were prospectively enrolled. Transitional cell carcinoma and its location on multidetector computerized tomography urography were recorded at a prospective reading with knowledge of the pertinent history and at a retrospective reading while blinded to all information. Histological evidence of transitional cell carcinoma served as the gold standard for final diagnosis. Patients who were lost to followup, refused biopsy/surgery for clinically suspicious neoplasms or had negative diagnostic evaluation but a followup of less than 1 year were excluded from study. We analyzed the diagnostic value of multidetector computerized tomography urography for transitional cell carcinoma by location with reference to final diagnosis. RESULTS A total of 139 patients were eligible for study, of whom 24 were excluded from analysis. There was no difference in demographic features between included and excluded patients. Of the 115 included patients 60 had a final diagnosis of a total of 77 transitional cell carcinomas in the renal pelvis, ureter or bladder. Overall sensitivity, specificity and accuracy of multidetector computerized tomography urography for diagnosing transitional cell carcinoma were 0.857, 0.980 and 0.963 at the retrospective reading, and 0.961, 0.988 and 0.984 at the prospective reading, respectively. Multidetector computerized tomography urography had the highest accuracy for diagnosing renal transitional cell carcinoma and the lowest sensitivity for detecting ureteral transitional cell carcinoma. CONCLUSIONS Multidetector computerized tomography urography is an accurate, noninvasive imaging modality for diagnosing transitional cell carcinoma in patients with gross hematuria. However, careful assessment of the ureter for multidetector computerized tomography urography is required for detecting ureteral transitional cell carcinoma.

Intracranial meningeal melanocytoma: CT and MRI

Abstract We report the MRI and CT findings of an intracranial meningeal melanocytoma (IMM) arising from Meckels cave and review the imaging characteristics of IMM. On CT, IMM constantly appear as well-circumscribed, isodense to slightly dense, extra-axial tumours with homogeneous contrast enhancement. This appearance is nonspecific and similar to that of meningiomas or small neuromas. On MRI, the signal of IMM is strongly related to the amount of melanin pigment: the more melanin, the more shortening of T1 and T2 relaxation times. Only when it shows as a homogeneous mass, bright on T1 and dark on T2 weighting, can a specific diagnosis of a melanin-containing tumour be made. However, this still cannot provide a distinction between IMM and malignant meningeal melanoma.

Repeat transcatheter arterial embolization for the management of pelvic arterial hemorrhage.

BACKGROUND Most arterial hemorrhage associated with pelvic fracture can be adequately controlled by a single transcatheter arterial embolization (TAE). However, there is a small group of patients who remain hemodynamically unstable after TAE, have no other identifiable source of bleeding, and who benefit from repeat TAE of the pelvis. METHODS We conducted a retrospective study of patients with hemorrhage from pelvic fractures between January 2001 and June 2006. Clinical parameters and results were compared between patients requiring more than one pelvic TAE and those undergoing a single TAE. Risk factors for repeat TAE were identified by univariate and stepwise logistic regression analyses. RESULTS During the study period, 174 of 964 patients with pelvic fracture received pelvic angiography for suspected arterial hemorrhage. One hundred forty TAEs were performed. Thirty-four (24.3%) patients underwent more than one angiography for suspected recurrent arterial hemorrhage, and 26 (18.6%) underwent repeat TAE. Repeat angiography was performed 3 to 58 hours (mean, 21 hours) after initial TAE. Patients with repeat TAE had significantly more blood transfusions, higher mortality rate, and longer intensive care unit stay. Independent predictors for repeat TAE included initial hemoglobin level lower than 7.5 g/dL (OR, 6.22), superselective arterial embolization in initial TAE (OR, 3.22), and more than 6 units of blood transfusion after initial TAE (OR, 3.22). CONCLUSION Careful monitoring and prompt recognition of patients requiring repeat TAE is paramount. The arterial access sheath should remain in place for up to 72 hours after angiography. Initial hemoglobin level lower than 7.5 g/dL and more than 6 units of blood transfusion after initial angiography are predictors for repeat TAE. Superselective TAE is associated with a significantly higher risk of recurrent hemorrhage, and its use should be limited.

Long-Term Changes of the Nonresurfaced Patella After Total Knee Arthroplasty

BACKGROUND The most common complications of total knee arthroplasty involve the patellofemoral joint. However, the long-term fate of the nonresurfaced patella after total knee arthroplasty has seldom been reported. The purpose of this study was to evaluate the long-term changes of the nonresurfaced patella after total knee arthroplasty. METHODS We retrospectively evaluated the nonresurfaced patella in 227 knees (181 patients) at an average of 8.5 years after total knee arthroplasty. Functional results were correlated with radiographic changes, and risk factors leading to abnormal changes of the patella were analyzed. RESULTS Preoperatively, 186 (82%) of the patellae tracked centrally, thirty-nine (17%) displaced or tilted laterally, and two (1%) subluxated laterally. At the time of the latest follow-up, 133 (59%) of the patellae still tracked centrally with preservation of the cartilage thickness, fifteen (7%) showed early lateral tilt, sixty-eight (30%) had progressive loss of lateral cartilage thickness with lateral tilt and/or displacement, seven (3%) had progressed to lateral subluxation, and four (2%) tilted medially. An abnormal patellofemoral joint did not affect the knee and functional scores (p = 0.90 and 0.89, respectively). However, symptoms such as difficulty rising from a chair or reluctance to use the involved lower limb while climbing stairs were noted. Preoperative patellar maltracking was identified as the only risk factor leading to postoperative patellar abnormalities (relative risk, 2.7; 95% confidence interval, 2.21 to 3.30; p = 0.003). CONCLUSIONS At the time of follow-up, at an average of 8.5 years, patellar tracking and the patellofemoral joint remained normal after approximately 60% of the total knee arthroplasties performed without resurfacing of the patella. Progressive degenerative changes of the nonresurfaced patella (mainly on the lateral facet) and patellar maltracking were the most common abnormal radiographic changes. Patients with preoperative patellar maltracking were at risk for the development of these changes and clinical symptoms. Resurfacing of the patella during total knee arthroplasty may benefit such patients.

Combined endoscopic and surgical treatment for the polyposis of Peutz-Jeghers syndrome.

Abstract Repeated laparotomy with extensive small bowel resectioning and eventual short-bowel syndrome is a major problem in Peutz-Jeghers syndrome (PJS) patients. This problem is caused by gastrointestinal polyposis with intussusception. A combined surgical and endoscopic approach can assess the extent of the polyposis, and small polyps can be removed by snare polypectomy. This can avert multiple enterotomies and decrease bowel resection segments. We applied an intraoperative colonscope via the enterotomy route in an 20-year-old PJS woman, and successfully removed the other 10 polyps distributed in the whole small bowel. As part of an aggressive approach to the management of polyposis in PJS, complete polypectomy can provide a longer symptom-free interval and remove potentially premaligment polyps.