Jer-Shyung Huang

Intramural Blood Pools Accompanying Aortic Intramural Hematoma: CT Appearance and Natural Course

PURPOSE To evaluate multidetector computed tomographic (CT) images to investigate the prevalence, morphology, natural course, and prognostic effect of intramural blood pools (IBPs) in patients with acute intramural hematoma (IMH). MATERIALS AND METHODS Institutional review board approval and written informed consent were obtained. Sixty-five patients (41 men; mean age, 65.9 years ± 11.3 [standard deviation]) with acute IMH undergoing three or more multidetector CT examinations during follow-up for 12 months or longer (median = 18 months), except for those undergoing surgery (n = 16), were enrolled. Associated factors of developing and resorption of IBP in IMH were analyzed by using logistic regression. RESULTS There were 40 IBPs in 10 patients at initial multidetector CT, and 15 new IBPs developed in 11 patients during follow-up. IBPs occurred most in the descending thoracic (55% [31 of 56]) and abdominal (41% [23 of 56]) aorta in 28% (18 of 65) of patients. During 33.8 months (range, 2.8-50 months) of follow-up in these 18 patients, 57% (32 of 56) of IBPs showed complete resorption in 15 patients, 29% (16 of 56) of IBPs showed incomplete resorption in eight patients, and 14% (eight of 56) of IBPs had interrupted follow-up because of surgery or death in three patients. Logistic regression showed that age younger than 70 years (odds ratio [OR], 8.74; 95% confidence interval [CI]: 1.03, 76.9) and IMH wall thickness greater than 10 mm (OR, 4.93; 95% CI: 1.04, 23.0) were associated with developing IBP at initial multidetector CT, while IBP with larger transmural diameter (OR, 1.16; 95% CI: 1.02, 1.31) and multidetector CT-demonstrated connection with intercostal or lumbar artery (63% [35 of 56]) (OR, 5.44; 95% CI: 1.43, 20.9) were associated with incomplete resorption. CONCLUSION IBPs are frequently observed at multidetector CT in patients with IMH. They may resolve over time or appear during follow-up. These findings are not associated with a poor prognosis, and IBPs should be distinguished from ulcerlike projections.

Clinical evaluation of contrast-enhanced digital mammography and contrast enhanced tomosynthesis—Comparison to contrast-enhanced breast MRI

PURPOSE To compare the diagnostic accuracy of contrast-enhanced digital mammography (CEDM) and contrast-enhanced tomosynthesis (CET) to dynamic contrast enhanced breast MRI (DCE-MRI) using a multireader-multicase study. METHODS Institutional review board approval and informed consents were obtained. Total 185 patients (mean age 51.3) with BI-RADS 4 or 5 lesions were evaluated before biopsy with mammography, tomosynthesis, CEDM, CET and DCE-MRI. Mediolateral-oblique and cranio-caudal views of the target breast CEDM and CET were acquired at 2 and 4 min after contrast agent injection. A mediolateral-oblique view of the non-target breast was taken at 6 min. Each lesion was scored with forced BI-RADS categories by three readers. Each reader interpreted lesions in the following order: mammography, tomosynthesis, CEDM, CET, and DCE-MRI during a single reading session. RESULTS Histology showed 81 cancers and 144 benign lesions in the study. Of the 81 malignant lesions, 44% (36/81) were invasive and 56% (45/81) were non-invasive. Areas under the ROC curve, averaged for the 3 readers, were as follows: 0.897 for DCE-MRI, 0.892 for CET, 0.878 for CEDM, 0.784 for tomosynthesis and 0.740 for mammography. Significant differences in AUC were found between the group of contrast enhanced modalities (CEDM, CET, DCE-MRI) and the unenhanced modalities (all p<0.05). No significant differences were found in AUC between DCE-MRI, CET and CEDM (all p>0.05). CONCLUSION CET and CEDM may be considered as an alternative modality to MRI for following up women with abnormal mammography. All three contrast modalities were superior in accuracy to conventional digital mammography with or without tomosynthesis.

Single-session alcohol-retention sclerotherapy for simple renal cysts: comparison of 2- and 4-hr retention techniques.

OBJECTIVE The objectives of our study were to evaluate the feasibility of ethanol sclerotherapy in treating simple renal cysts with prolonged ethanol retention and to compare the therapeutic results of 2- and 4-hr retention techniques. MATERIALS AND METHODS We retrospectively reviewed 36 renal cysts in 33 patients treated by ethanol sclerotherapy with a single-session single-injection technique during the past 6 years. After complete aspiration of the cystic fluid, 95% ethanol was injected into the cyst and was retained for 4 hr in 14 cysts (group 1) and for 2 hr in 22 cysts (group 2). The average maximal diameter and aspirated volume of the cysts were 8.3 cm and 223 mL in group 1 patients and 7.9 cm and 167 mL in group 2, respectively. The ablated cysts were followed up regularly by sonography, CT, or both at 3- to 6-month intervals for at least 1 year. The nonparametric Mann-Whitney U test was used to compare differences in characteristics, treatment results, and laboratory data of the subjects in the two groups. The level of statistical significance was set at a p value of less than 0.05. RESULTS Technically, all the patients tolerated the procedures. One patient had gross hematuria 10 days after the procedure. She underwent surgical deroofing treatment and was excluded in the later statistical analysis. After sclerotherapy, 14 cysts disappeared completely and 16 cysts showed marked regression with residual maximal diameter of less than 3 cm. The overall volume reduction rate was 97.6% in all 35 cysts. The mean residual longest diameters and average volume reduction rates of the treated cysts were 1.9 cm and 97.9% in group 1 patients and 1.1 cm and 97.3% in group 2 patients, respectively, which showed no statistical significance of volume reduction rate with a p value 0.149. CONCLUSION The single-session prolonged ethanol-retention technique is safe and efficacious for the treatment of renal cysts. There is no statistical difference in therapeutic efficacy between 2- and 4-hr ethanol-retention techniques.

Single-dose time-resolved contrast enhanced hybrid MR angiography in diagnosis of peripheral arterial disease: Compared with digital subtraction angiography

To prospectively study the diagnostic performance of hybrid single‐dose contrast‐enhanced MRA of peripheral arterial disease (PAD), with digital subtraction angiography (DSA) as the reference standard.

The efficacy and long-term outcome of microcoil embolotherapy for acute lower gastrointestinal bleeding.

Objective To evaluate the clinical efficacy as well as long-term clinical outcomes of superselective microcoil embolization for lower gastrointestinal bleeding (LGIB). Materials and Methods Between 1997 and 2009, 26 patients with intended transcatheter embolotherapy for LGIB were retrospectively reviewed. Embolization was performed only when the catheter could be advanced to or distal to the mesenteric border of the bowel. The main purpose of our study was to assess technical success, recurrent bleeding rate and complications. We also evaluated the long-term clinical outcome, including late recurrent LGIB, bowel ischemia and the survival rate. Results Twenty-two bleeding sources were in the territory of superior mesenteric artery and four in the inferior mesenteric artery. Technical success was achieved in 22 patients (84.6%). The target vessel of embolization was vasa recta in seventeen patients and marginal artery in the remaining five patients. Early rebleeding occurred in two patients (7.7%) and bowel ischemia in two patients, of whom the embolized points were both at the marginal artery. Delayed recurrent bleeding (> 30 days) occurred in two angiodysplasia patients. Five patients (19.2%) died within the first 30 days of intervention. Long-term follow-up depicted estimated survival rates of 58.2 and 43.1% after one, and five years, respectively. Conclusion Transcatheter embolotherapy to treat LGIB is effective with low rebleeding and ischemic complications. Considering the advanced age and complex medical problems of these patients, the minimal invasive embolotherapy may be used as both a primary and potentially definitive treatment of LGIB.

Fluoroscopic Guidance of Retrograde Exchange of Ureteral Stents in Women

OBJECTIVE The purpose of this study was to review our experience with fluoroscopically guided retrograde exchange of ureteral stents in women. MATERIALS AND METHODS During a 48-month period, 28 women (age range, 38-76 years) were referred to our department for retrograde exchange of a ureteral stent. The causes of urinary obstruction were tumor compression in 26 patients and benign fibrotic stricture in two patients. A large-diameter snare catheter (25-mm single loop or 18- to 35-mm triple loop) or a foreign body retrieval forceps (opening width, 11.3 mm) was used to grasp the bladder end of the stent under fluoroscopic guidance. The technique entailed replacement of a patent or occluded ureteral stent with a 0.035- or 0.018-inch guidewire with or without the aid of advancement of an angiographic sheath. RESULTS A total of 54 ureteral stents were exchanged with a snare catheter in 42 cases or a forceps in 12 cases. One stent misplaced too far up the ureter was replaced successfully through antegrade percutaneous nephrostomy. Ten occluded stents, including one single-J stent, were managed with a 0.018-inch guidewire in three cases, advancement of an angiographic sheath over the occluded stent into the ureter in five cases, and recannulation of the ureteral orifice with a guidewire in two cases. No complications of massive hemorrhage, ureter perforation, or infection were encountered. CONCLUSION With proper selection of a snare or forceps catheter, retrograde exchange of ureteral stents in women can be easily performed under fluoroscopic guidance with high technical success and a low complication rate.

The outcome of a quality-controlled mammography screening program: Experience from a population-based study in Taiwan

Background: A greater policy of emphasis on the early detection and treatment of breast cancer is prevalent among developed countries. To raise the screening performance with a potentially decreased mortality rate, it is crucial to evaluate and analyze the screening outcome after implementation. We report the clinical outcome of an 8‐year nationwide mammography screening in Taiwan to help share our statistical information on breast screening worldwide, especially in Asia. Methods: Taiwan has provided nationwide, free, biennial mammographic screening since 2004. A total of 2,392,789 consecutive screening mammography examinations were performed during this study period for women aged 50–69 years (2006–2009) and 45–69 years (from December 2009 onwards). The screening covers 33.2% of the target population in the most recent 2 years. The workload of every screening radiologist, the overall recall rate, positive predictive value (PPV1), cancer detection rate (CDR), cancer incidence rate (CIR) from the screening, 1‐year interval cancer, sensitivity, and specificity of the screening mammography are calculated, and compared with the American College of Radiology (ACR) recommendation level and/or those of other screening mammographic series. Results: The CDRs (%) and CIRs (%) increased from 3.94–4.08 and 4.80–5.04 to 4.71–5.04 and 5.71 after 2009, implying a high occurrence of breast cancer in the younger age group of 45–49 years. The recall rates (9.3–10.0%) in this review are within the ACR recommendation range (<10%) and the PPV1 has also reached the ACR recommended level (>5%) in the most recent 2 years. The improvement of the screening performance may be attributed to our peer auditing review and education program. The sensitivity of our screening mammography is slightly lower than that of the ACR recommended level (>85%), which is still comparable to the results of the Vermont area in the USA. Although the workload (screenees/screeners) for every radiologist each year has increased from 150 in 2004 to 1360 in 2012, it does not seem to worsen the quality outcome of this screening program. Conclusion: From the outcome review of this national mammography screening, there is still room to ameliorate our performance through comprehensive and continued education, to improve the competence of cancer detection and decrease false negative (FN) cases.

Percutaneous retrieval of dislodged central venous port catheter: experience of 25 patients in a single institute:

Background: For a dislodged port catheter, percutaneous retrieval by using a loop snare or a basket is the standard technique, with high success. However, once a loop snare fails, the likelihood of success with other tools is considered low. Purpose: To report our experience of percutaneous retrieval of dislodged port catheters and to emphasize the usefulness of grasping forceps. Material and Methods: During a 6-year period, a total of 25 dislodged port catheters were retrieved in our institute. The interval between port catheter implantation and dislodged catheter retrieval was 3–85 months (mean 23 months). The time of delayed retrieval ranged from 3 to 604 days (mean 58 days). A loop snare or grasping forceps were used via either the femoral or jugular route. Results: The prevalence of port catheter dislodgement was 0.4% in our institute. All dislodged port catheters were successfully removed, including four patients with delayed retrieval of more than 90 days. A loop snare was used in 20 patients, with technical success in 18. Grasping forceps were used in seven patients, all with success (including the two patients who failed by initial use of a loop snare). No procedure-related complications were encountered, except transient arrhythmia in four patients requiring no medication. Conclusion: Although the prevalence of port catheter dislodgement is low, percutaneous attempts at retrieval should be performed in all patients, even in chronic settings. A loop snare is the instrument of choice for retrieval. Grasping forceps can be used as an auxiliary instrument, especially in patients where a loop snare fails.

Ureteral fibroepithelial polyp diagnosed preoperatively on virtual CT ureteroscopy

We report a 28-year-old man who presented with hematuria and intermittent flank pain. Conventional CT urography showed mild left hydronephrosis and an undetermined lesion in the left ureter. By virtual CT ureteroscopy, a fibroepithelial polyp (FEP) was preoperatively diagnosed. The patient had segmental resection of the ureter and pathological proof of FEP was obtained.

Imaging findings of primary urachal actinomycosis.

Primary actinomycosis in urachal remnant is documented rarely in the English literature. The disease is usually misdiagnosed as urachal carcinoma because of its infiltrating and enhancing natures. We illustrate a case of urachal actinomycosis with ultrasound, computed tomography, and magnetic resonance images. The clinical, radiological, and pathological findings are reviewed. Some imaging findings may help us to differentiate an inflammatory process from malignancy.