Jae Kyu Kim

Contrast Enhancement and Contrast Extravasation on Computed Tomography After Intra-Arterial Thrombolysis in Patients With Acute Ischemic Stroke

Background and Purpose— The goal of this study was to determine the CT findings and clinical consequences of contrast enhancement and contrast extravasation on CT scans obtained after intra-arterial thrombolytic therapy for treatment of acute ischemic stroke. Methods— Sixty-two patients were treated with intra-arterial thrombolysis. All patients underwent nonenhanced CT scans immediately and 24 hours after thrombolytic therapy. Contrast enhancement was defined as a hyperdense lesion that disappeared on a 24-hour follow-up CT scan. Contrast extravasation was defined as a hyperdense lesion with maximum Hounsfield unit >90 that persisted on a follow-up CT scan. We evaluated the differences in the clinical and radiological data between 3 groups: contrast enhancement, contrast extravasation, and control groups. Results— Contrast enhancement was found in 14 of 62 patients (22.6%); contrast extravasation was seen in 7 (11.3%). Compared with the control group, the contrast enhancement group had a lower recanalization grade (64.3% versus 34.1%, P =0.048) and a lower incidence of hemorrhagic transformation (14.3% versus 43.9%, P =0.047). The contrast extravasation group had a higher incidence of both hemorrhage (100% versus 43.9%, P =0.006) and symptomatic hemorrhage (100% versus 14.6%, P <0.001) than the control group. Poor outcomes were more frequent in the contrast extravasation group (100% versus 38.9%, P =0.003) than the control group. Conclusions— Contrast enhancement on CT scans obtained after intra-arterial thrombolysis is usually not associated with hemorrhagic complications. However, contrast extravasation is highly associated with parenchymatous hematoma and should be considered a negative prognostic sign.

FDG PET/CT for the Detection and Evaluation of Breast Diseases: Usefulness and Limitations

Positron emission tomography (PET) with fluorine 18 fluorodeoxyglucose (FDG) is used to diagnose, stage, and monitor breast cancer. FDG PET has the capability to depict abnormal metabolic activity before any anatomic change occurs; however, in the absence of identifiable anatomic structures on PET images, it may be impossible to identify the location of areas of increased radionuclide uptake. In such cases, the coregistration of PET images with images from computed tomography (CT) may help improve diagnostic accuracy and lead to better clinical management of patients with breast cancer. Although FDG PET/CT may have limited diagnostic value for detecting small primary breast tumors, well-differentiated breast cancer, or regional lymph node involvement, it is superior to conventional imaging modalities for detecting distant metastases and recurrences and for monitoring the response to therapy.

Imaging features of hepatocellular carcinoma after transcatheter arterial chemoembolization and radiofrequency ablation.

OBJECTIVE The purpose of this pictorial essay is to show the imaging features of hepatocellular carcinoma (HCC) after transcatheter arterial chemoembolization (TACE) and radiofrequency thermal ablation on CT, MRI, and contrast-enhanced sonography and to describe the advantages and limitations of each imaging technique in evaluating the therapeutic effect on HCC. CONCLUSION CT is the standard imaging technique for monitoring the effectiveness of TACE and radiofrequency ablation. Contrast-enhanced sonography and MRI can complement CT in evaluating the therapeutic response.

Hepatic undifferentiated embryonal sarcoma : MR findings

We report the MR findings of undifferentiated embryonal sarcoma of the liver. A 15-year-old boy presented with a palpable mass in the right upper quadrant of the abdomen. A T1-weighted MR image showed a well defined hypointense mass with scattered high signal intensities in the left hepatic lobe. On T2-weighted imaging, the tumor changed to a hyperintense mass. Postcontrast T1-weighted imaging showed irregular enhancement of the solid portion of the mass. MR findings are correlated with those of angiography, US, CT, and pathology.

Radiofrequency Ablation Combined with Transcatheter Arterial Chemoembolization for the Treatment of Single Hepatocellular Carcinoma of 2 to 5 cm in Diameter: Comparison with Surgical Resection

Objective To compare the effectiveness of radiofrequency ablation (RFA) combined with transcatheter arterial chemoembolization (TACE) with surgical resection in patients with a single hepatocellular carcinoma (HCC) ranging from 2 to 5 cm. Materials and Methods The study participants were enrolled over a period of 29 months and were comprised of 37 patients in a combined therapy group and 47 patients in a surgical resection group. RFA was performed the day after TACE, and surgical resection was performed by open laparotomy. The two groups were compared with respect to the length of hospital stay, rates of major complication, and rates of recurrence-free and overall survival. Results Major complications occurred more frequently in the surgical resection group (14.9%) than in the combined therapy group (2.7%). However, there was no statistical significance (p = 0.059). The rates of recurrence-free survival at 1, 2, 3 and 4 years were similar between the combined therapy group (89.2%, 75.2%, 69.4% and 69.4%, respectively) and the surgical resection group (81.8%, 68.5%, 68.5% and 65%, respectively) (p = 0.7962, log-rank test). The overall survival rates at 1, 2, 3 and 4 years were also similar between groups (97.3%, 86.5%, 78.4% and 78.4%, respectively, in the combined therapy group, and 95.7%, 89.4%, 84.3% and 80.3%, respectively, in the surgical resection group) (p = 0.6321, log-rank test). Conclusion When compared with surgical resection for the treatment of a single HCC ranging from 2 to 5 cm, RFA combined with TACE shows similar results in terms of recurrence-free and overall survival rates.

Acute Small Bowel Hemorrhage in Three Patients with End-Stage Renal Disease: Diagnosis and Management by Angiographic Intervention

Three patients who had undergone hemodialysis for end-stage renal disease, presented with acute small bowel hemorrhage, and were treated with superselective transcatheter arterial embolization via coaxial microcatheters. In all patients pre-procedure upper gastrointestinal (GI) endoscopy and colonoscopy had failed to demonstrate the source of the hemorrhage. Selective diagnostic angiography revealed frank extravasations of contrast from the small bowel arteries (one jejunal artery and two ileal arteries). After superselection of feeding arteries with a microcatheter, transcatheter embolization using Gelfoam and microcoils was performed in all three patients. Immediate hemostasis was achieved in all patients and the patients were discharged free from symptoms 3–5 days after embolization. No evidence of intestinal ischemia or infarction was noted, with the time from procedure to last follow-up ranging from 4 to 12 months. We conclude that superselective angiography is a valuable tool for diagnosing and treating acute small bowel hemorrhage in patients with end-stage renal disease when endoscopic evaluation has failed.

Effect of Ultrasound-Guided Radiofrequency Ablation in Incompletely Treated Hepatocellular Carcinoma after Transcatheter Arterial Chemoembolization

Objective To evaluate the effectiveness of ultrasound-guided radiofrequency (RF) ablation in patients with incompletely treated hepatocellular carcinoma (HCC) after transcatheter arterial chemoembolization (TACE) and to evaluate possible prognostic factors for this therapy. Subjects and Methods Thirty nine patients with incompletely treated single HCC (≤ 5 cm) after TACE were treated with RF ablation. All patients were evaluated for complete tumor ablation rate, local recurrence-free rate, overall survival rate, and complications. Local recurrence-free rate and overall survival rate were calculated using the Kaplan-Meier method. The possible prognostic factors of local recurrence-free rate and survival rate were analyzed using Cox proportional-hazards regression model. Results The complete tumor ablation rate was 92.3%. Local recurrence-free rates for 1-, 2-, 3-, and 5-years were 81.7%, 63.1%, 53.6%, and 35.7%, respectively. One-, 2-, 3-, and 5-year overall survival rates were 96.9%, 82.9%, 67.8%, and 48.4%, respectively. Among prognostic factors included in the analysis, only tumor diameter (≤ 2 cm versus > 2 cm) was statistically significant in terms of predicting local recurrence. Complications were observed in two patients, one with liver abscess and the other with portal venous thrombosis. Conclusion Ultrasound-guided RF ablation could be effective and safe in treating incompletely treated HCC after TACE. The diameter of HCC was a significant prognostic factor for local recurrence.

Hematemesis Due to a Pseudoaneurysm of the Splenic Artery Secondary to Gastric Tuberculosis

Gastric tuberculosis (TB) is very rare compared with other sites in the gastrointestinal (GI) tract, and upper GI bleeding is an extremely rare manifestation of gastric TB. Also, a pseudoaneurysm is an uncommon cause of GI bleeding and is often encountered with pancreatitis. To our knowledge, no case of GI bleeding due to a pseudoaneurysm of the splenic artery secondary to gastric TB has been reported previously. We report a patient who presented with hematemesis due to a pseudoaneurysm of the splenic artery secondary to gastric TB.

Retrograde Tempofilter II™ Placement within the Superior Vena Cava in a Patient with Acute Upper Extremity Deep Venous Thrombosis: the Filter Stands on Its Head

The Tempofilter II is a widely used temporary vena cava filter. Its unique design, which includes a long tethering catheter with a subcutaneous anchor, facilitates the deployment and retrieval of the device. Despite this, the Tempofilter II has been used only in the inferior vena cava of patients with lower extremity deep venous thrombosis. In this article, we present a case of superior vena cava filtering using the Tempofilter II in patients with upper extremity deep venous thrombosis.

Fracture of a Tempofilter II: an Initial Case Report

Tempofilter II is a device that is used for pulmonary embolism prophylaxis. Since the appearance of the Tempofilter II following withdrawal of the Tempofilter I, it has been reported that the Tempofilter II is safe, effective and useful. Here we report on the first case of a fracture of one leg of the filter and this leg was embedded in the inferior vena cava wall in a 62-year-old man with deep vein thrombosis.