Tsung-Lung Yang

The Adjunctive Digital Breast Tomosynthesis in Diagnosis of Breast Cancer

Purpose. To compare the diagnostic performance of digital breast tomosynthesis (DBT) and digital mammography (DM) for breast cancers. Materials and Methods. Fifty-seven female patients with pathologically proved breast cancer were enrolled. Three readers gave a subjective assessment superiority of the index lesions (mass, focal asymmetry, architectural distortion, or calcifications) and a forced BIRADS score, based on DM reading alone and with additional DBT information. The relevance between BIRADS category and index lesions of breast cancer was compared by chi-square test. Result. A total of 59 breast cancers were reviewed, including 17 (28.8%) mass lesions, 12 (20.3%) focal asymmetry/density, 6 (10.2%) architecture distortion, 23 (39.0%) calcifications, and 1 (1.7%) intracystic tumor. Combo DBT was perceived to be more informative in 58.8% mass lesions, 83.3% density, 94.4% architecture distortion, and only 11.6% calcifications. As to the forced BIRADS score, 84.4% BIRADS 0 on DM was upgraded to BIRADS 4 or 5 on DBT, whereas only 27.3% BIRADS 4A on DM was upgraded on DBT, as BIRADS 4A lesions were mostly calcifications. A significant P value (<0.001) between the BIRADS category and index lesions was noted. Conclusion. Adjunctive DBT gives exquisite information for mass lesion, focal asymmetry, and/or architecture distortion to improve the diagnostic performance in mammography.

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.

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.

Redefining the sonography workflow through the application of a departmental computerized workflow management system

PURPOSE The purpose of this study is to demonstrate and evaluate the effective application of a computerized workflow management system (WMS) into sonography workflow in order to reduce patient exam waiting time, number of waiting patients, sonographer stress level, and to improve patient satisfaction. METHODS A computerized WMS was built with seamless integration of an automated patient sorting algorithm, a real-time monitoring system, exam schedules fine-tuning, a tele-imaging support system, and a digital signage broadcasting system of patient education programs. The computerized WMS was designed to facilitate problem-solving through continuous customization and flexible adjustment capability. Its effects on operations, staff stress, and patient satisfaction were studied. RESULTS After implementation of the computerized WMS, there is a significant decrease in patient exam waiting time and sonographer stress level, significant increase in patient satisfaction regarding exam waiting time and the number of examined patients, and marked decrease in the number of waiting patients at different time points in a day. CONCLUSION Through multidisciplinary teamwork, the computerized WMS provides a simple and effective approach that can overcome jammed exams associated problems, increase patient satisfaction level, and decrease staff workload stress under limited resources, eventually creating a win-win situation for both the patients and radiology personnel.

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.

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.

Antegrade Retrieval of Ureteral Stents Through an 8-French Percutaneous Nephrostomy Route

OBJECTIVE The purpose of this study was to describe the technique of antegrade retrieval of ureteral stents under fluoroscopic guidance through an 8-French nephrostomy. MATERIALS AND METHODS During an 8-year period, we retrieved 26 ureteral stents from 24 patients who were not candidates for retrograde removal or had other conditions precluding use of a retrograde approach. A loop snare or grasping forceps was used to retrieve a ureteral stent in the renal pelvis or calyx or upper ureter through an 8-French vascular sheath with a safety wire in place. A snare catheter advanced into the bladder for retrieval of the bladder end was used in patients in whom retrieval with both a loop snare and a grasping forceps failed. RESULTS All 26 ureteral stents were successfully retrieved by the antegrade approach. Ten stents were retrieved with a snare alone and nine with a forceps alone. Five stents were retrieved successfully with a forceps after initial failures with snare catheters. Two stents were retrieved with snare catheters advanced into the bladder. The major complication of nephrostomy wound infection occurred in a patient with a urinary tract infection who underwent a one-stage procedure. All minor complications, including pelvic perforation in one patient and blood clot in the renal pelvis in four patients, resolved spontaneously without adverse sequelae. CONCLUSION Antegrade percutaneous retrieval of a ureteral stent through an 8-French nephrostomy is safe and effective and has a high degree of technical success. It can be used as a routine interventional practice in radiology.

Differentiation between pelvic abscesses and pelvic tumors with diffusion-weighted MR imaging: a preliminary study

PURPOSE Use diffusion-weighted magnetic resonance imaging (MRI) in differentiating pelvic abscess from pelvic cystic tumor. MATERIALS AND METHODS Patients with pelvic abscess (n=23) or pelvic cystic tumor (n=15) who underwent diffusion-weighted MRI were reviewed. RESULTS Pelvic abscesses showed hyperintensity on diffusion-weighted MRI and hypointensity on apparent diffusion coefficient (ADC) map. The mean ADC values of fluid in pelvic abscess and pelvic tumors were 0.73 ± 0.15 × 10(-3) and 2.27 ± 0.45 × 10(-3) mm(2)/s, respectively. Pelvic abscesses had significantly lower ADC values than pelvic cystic tumors (P<.001). CONCLUSION Diffusion-weighted MRI provides a noncontrast method for interpreting pelvic cystic lesions.

Easily recognizable sonographic patterns of ductal carcinoma in situ of the breast

Background Ductal carcinoma in situ (DCIS) is a malignant proliferation of ductal epithelium confined by the basement membrane of the involved breast ducts. The aim of this study was to categorize positive findings of DCIS of the breast on sonography. Methods From 2007 to 2011, 100 pathologically proven DCIS lesions were evaluated. Four sonographic patterns used to identify DCIS have been characterized as cumulus‐type, coral‐type, pipe‐type, and miscellaneous lesions. Results The lesion numbers of nonhigh‐grade and high‐grade DCIS were 44 and 56, respectively. The coral type (42%) was the most commonly found lesion, followed by cumulus‐type (38%), pipe‐type (17%), and miscellaneous (3%) lesions. There was no significant difference between the sonographic pattern and nuclear grades. However, the coral‐type group was composed of significantly more high‐grade DCIS cases than the other three types (p < 0.05). Conclusion Coral‐, cumulus‐, and pipe‐type lesions are three easily recognizable sonographic findings of DCIS. Improving the breast ultrasound technique to better demonstrate the sonographic pattern is necessary to facilitate breast lesion interpretation.

Clinical roles of breast 3T MRI, FDG PET/CT, and breast ultrasound for asymptomatic women with an abnormal screening mammogram.

Background Magnetic resonance imaging (MRI) and fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) show promise for molecular cancer imaging. We evaluated 3T MRI, FDG PET/CT, and ultrasound images for asymptomatic women with an abnormal screening mammogram. Methods The Institutional Review Board of Kaohsiung Veterans General Hospital (Kaohsiung, Taiwan) approved the study. Patients provided written informed consent. A total of 11,865 screening mammograms of 118,65 women were performed at our facility between January 2011 and December 2012. Fifty‐three asymptomatic women (mean age, 53.3 years) whose screening mammograms had a Breast Imaging Reporting and Data System (BI‐RADS) category of 4 or 5 were ultimately enrolled in this study. Breast 3T MRI, FDG PET/CT, and breast ultrasound were performed before biopsy. All imaging modalities were compared by lesion‐by‐lesion analyses. Results Fifty‐nine breast lesions (28 malignant and 31 benign lesions) from 53 women were analyzed. The sensitivity, specificity, and accuracy for 28 breast cancers were 96%, 77%, and 86%, respectively, for breast 3T MRI; 50%, 100%, and 76%, respectively, for FDG PET,CT; and 61%, 87%, and 74%, respectively, for breast ultrasound. One 0.8‐cm invasive breast cancer was missed by the screening mammogram, but detected by breast 3T MRI and FDG PET/CT. The sensitivity for detecting breast cancer was significantly higher with MRI than with PET/CT or ultrasound (for all, p < 0.01). The specificity for detecting breast cancer was significantly higher for PET/CT than for breast MRI (p = 0.02). The sensitivity exhibited by 3T breast MRI and FDG PET/CT for 16 noninvasive breast cancers was 94% and 25%, respectively. Conclusion On screening mammograms, breast 3T MRI showed higher sensitivity but less specificity than FDG PET/CT for detecting asymptomatic breast cancers.