WAVELET-BASED AUTOMATIC PECTORAL MUSCLE SEGMENTATION FOR MAMMOGRAMS.

The computational analysis to assist radiologists in the interpretation of mammograms usually requires a pre-processing step where the image is converted into a black and white mask to separate breast tissue from the pectoral muscle and the image background. The manual delineation of the breast tissue from the mammogram image is subjective and time-consuming. The 2D Wavelet Transform Modulus Maxima (WTMM) segmentation method, a powerful and versatile multi-scale edge detection approach, is adapted and presented as a novel automated breast tissue segmentation method. The algorithm computes the local maxima of the modulus of the continuous Gaussian wavelet transform to produce candidate edge detection lines called maxima chains. These maxima chains from multiple wavelet scales are optimally sorted to produce a breast tissue segmentation mask. The mammographic mask is quantitatively compared to a manual delineation using the Dice-Sorenson Coefficient (DSC). The adaptation of the 2D WTMM segmentation method produces a median DSC of 0.9763 on 1042 mediolateral oblique (MLO) 2D Full Field Digital mammographic views from 82 patients obtained from the MaineHealth Biobank (Scarborough, Maine, USA). Our proposed approach is evaluated against OpenBreast , an open-source automated analysis software in MATLAB, through comparing each approach's masks to the manual delineations. OpenBreast produces a lower median DSC of 0.9710. To determine statistical significance, the analysis is restricted to 82 mammograms (one randomly chosen per patient), which yields DSC medians of 0.9756 for the WTMM approach vs. 0.9698 for OpenBreast ( p -value = 0.0067 using a paired Wilcoxon Rank Sum test). Thus, the 2D WTMM segmentation method can reliably delineate the pectoral muscle and produce an accurate segmentation of whole breast tissue in mammograms.

Longitudinal Case-Control Study of Active and Passive Dense Mammographic Breast Tissue.

Mammography is used as secondary prevention for breast cancer. Computer-aided detection and image-based short-term risk estimation were developed to improve the accuracy of mammography. However, most approaches inherently lack the ability to connect observations at the mammography level to observations of cancer onset and progression seen at a smaller scale, which can occur years before imageable cancer and lead to primary prevention. The Hurst exponent (H) can quantify mammographic tissue into regions of dense tissue undergoing active restructuring and regions that remain passive, with amounts of active and passive dense tissue that differ between cancer and controls at diagnosis. A longitudinal retrospective case-control study was conducted to test the hypothesis that differences can be detected before diagnosis and changes could signal developing cancer. Mammograms and reports were collected from 50 patients from Maine Medical Center in 2015 with at least a 5-year screening history. Age-matching patients within 2 years created a primary dataset, and within 5 years, a secondary dataset was created to test for sensitivity. The amount of passive (H≥0.55) and active dense tissue (0.45

CT esophagogram in the emergency setting: typical findings and suggested workflow.

PURPOSE: Esophageal perforation (EP) can be a diagnostic challenge. Computed tomography (CT) and CT esophagography (CTE) are often used to rule out EP in the emergency setting with promising diagnostic performance, but the standard of care remains fluoroscopic esophagography (FE). We assess the diagnostic performance of CT and CTE when interpreted by expert and generalist radiologists and created an imaging workflow guide. METHODS: Retrospective study of patients presenting with suspected EP. Two expert radiologists independently reviewed blinded CT/CTE studies, recorded CT findings, and assigned an esophageal injury grade. We also collected initial (general radiologist) CT findings and interpretation and FE diagnoses. We assessed inter-reader reliability and diagnostic performance. RESULTS: EP was diagnosed in 46/139 (33%) encounters. The most common CT/CTE findings in EP were esophageal wall thickening (46/46, 100%), pneumomediastinum (42/46, 91%), and mediastinal stranding (39/46, 85%). CT and CTE sensitivity for detecting EP was 89% and 89% for expert radiologists, respectively, and 79% and 82% for general radiologists, compared with 46% for FE. Inter-reader agreement for detecting EP by CT and CTE was kappa 0.35 and 0.42 (both p < .001) between expert and generalist radiologists. We present radiographic images for key CT/CTE findings and a suggested workflow for the evaluation of possible EP. CONCLUSION: CT and CTE are more sensitive than FE for EP in the emergency setting. Due to the rarity of EP and current wide variability in imaging interpretation, an imaging workflow and injury grading system based on esophageal and mediastinal CT findings are offered to help guide management.

Percutaneous umbilical blood sampling: current trends and outcomes.

OBJECTIVES: To report our contemporary experience with PUBS, including indications and complications, stratified by the presence of hydrops fetalis. STUDY DESIGN: All PUBS performed from 1988 to 2013 at a single tertiary care center were identified using a comprehensive ultrasound database. We recorded patient demographics, relevant obstetric, fetal and neonatal data, indication for and success of PUBS and any complications. Data were analyzed using SAS, version 9.3 (SAS Institute Inc., Cary, NC). RESULTS: 455 PUBS were performed on 208 pregnant women, 97.8% of which were successful. The average gestational age at the time of PUBS was 26.7 weeks (SD 5.1 weeks, range 17.5-41.3 weeks). Indications were available for 441: 245 (55.6%) isoimmunization, 77 (17.5%) non-immune hydrops fetalis (NIHF), 98 (22.2%) chromosomal diagnosis, and 21 (4.8%) other indications. Isoimmunization was a less common indication for PUBS in 2008-2013 as compared to 1988-1992 (51.7% vs 66.2%, p=0.07). Amongst PUBS performed in the setting of hydrops, isoimmunization was much less common in the later time period (61.1% vs 0%, respectively; p<0.01). The procedure complication rate (bradycardia or fetal demise at procedure) of 2.5% was stable over the study period and was most common with NIHF (2.0% without hydrops, 0% with immune hydrops and 6.3% with NIHF; p=0.04). Of the 208 women with a PUBS performed, 74 had more than one PUBS procedure (mean 2.2, max 18). Transfusions were performed in 233 of the 455 (51.2%). Overall, 10.2% of the pregnancies had an intrauterine fetal demise (IUFD) within 2 weeks of the procedure, which was most common in pregnancies with NIHF (3.2% without hydrops, 9.1% with immune hydrops and 31.7% with NIHF; p<0.01). The IUFD rate was 60% (3/5) in fetuses with parvovirus-mediated NIHF. CONCLUSIONS: PUBS has a high likelihood of success with a relatively low complication rate. The complication rate is highest in pregnancies with NIHF, and these pregnancies are also at a significantly higher risk of IUFD, particularly those patients with parvovirus-mediated NIHF. Our findings can be used when counseling patients who are considering PUBS for diagnostic or therapeutic purposes.

Quality Measurements in Radiology: A Systematic Review of the Literature and Survey of Radiology Benefit Management Groups.

PURPOSE: As the US health care system transitions toward value-based reimbursement, there is an increasing need for metrics to quantify health care quality. Within radiology, many quality metrics are in use, and still more have been proposed, but there have been limited attempts to systematically inventory these measures and classify them using a standard framework. The purpose of this study was to develop an exhaustive inventory of public and private sector imaging quality metrics classified according to the classic Donabedian framework (structure, process, and outcome). METHODS: A systematic review was performed in which eligibility criteria included published articles (from 2000 onward) from multiple databases. Studies were double-read, with discrepancies resolved by consensus. For the radiology benefit management group (RBM) survey, the six known companies nationally were surveyed. Outcome measures were organized on the basis of standard categories (structure, process, and outcome) and reported using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. RESULTS: The search strategy yielded 1,816 citations; review yielded 110 reports (29 included for final analysis). Three of six RBMs (50%) responded to the survey; the websites of the other RBMs were searched for additional metrics. Seventy-five unique metrics were reported: 35 structure (46%), 20 outcome (27%), and 20 process (27%) metrics. For RBMs, 35 metrics were reported: 27 structure (77%), 4 process (11%), and 4 outcome (11%) metrics. The most commonly cited structure, process, and outcome metrics included ACR accreditation (37%), ACR Appropriateness Criteria (85%), and peer review (95%), respectively. CONCLUSIONS: Imaging quality metrics are more likely to be structural (46%) than process (27%) or outcome (27%) based (P < .05). As national value-based reimbursement programs increasingly emphasize outcome-based metrics, radiologists must keep pace by developing the data infrastructure required to collect outcome-based quality metrics.

Business of radiology 101: the state of radiology business practice and health care policy curricula at US radiology residency programs.

PURPOSE: The aim of this study was to assess the prevalence, content, and perceptions of curricula focused on radiology business practice and health care policy at US radiology residency training programs. METHODS: The desired survey population was trainees and faculty members of radiology residency programs in the United States. Three anonymous survey instruments were distributed, including an e-mail survey to the membership of the ACR RFS, a paper survey to ACR RFS delegates attending the 2010 AMCLC, and an e-mail survey to the membership of the Association of Program Directors in Radiology (APDR). RESULTS: Response rates for the surveys were 12%, 25%, and 21%, respectively. Members of the APDR and RFS agreed that understanding and competency in business practice and health care policy topics are important to the future careers of residents (total favorable sentiment >86% for APDR members and >96% for RFS members). Most survey respondents' home institutions offer some form of a noninterpretive curriculum (91% of APDR respondents, 74% of RFS respondents), but the breadth of topics addressed and educational time devoted to these curricula were quite variable. Subjective effectiveness of curricula was infrequently rated as very effective by 12% of APDR respondents and 6% of RFS respondents. CONCLUSIONS: Despite the perceived importance of radiology business practice and health care policy education, and residency training requirements in competencies related to these subjects that have been in place for more than a decade, curricula addressing these items still seem to be in a stage of acceptance and development. Further commitment to and innovation within these curricula are requisite in educating our future radiologists.

Axillary ultrasound and fine-needle aspiration in the preoperative evaluation of the breast cancer patient: an algorithm based on tumor size and lymph node appearance.

OBJECTIVE: The objective of our study was to evaluate the utility of ultrasound-guided fine-needle aspiration (FNA) of the axillary lymph nodes in breast cancer patients depending on the size of the primary tumor and the appearance of the lymph nodes. SUBJECTS AND METHODS: Data were collected about tumor size, lymph node appearance, and the results of ultrasound-guided FNA and axillary surgery of 224 patients with breast cancer undergoing 226 ultrasound-guided FNA. Lymph nodes were classified as benign if the cortex was even and measured < 3 mm, indeterminate if the cortex was even but measured ≥ 3 mm or measured < 3 mm but was focally thickened, and suspicious if the cortex was focally thickened and measured ≥ 3 mm or the fatty hilum was absent. The results of ultrasound-guided FNAs were analyzed by the sonographic appearance of the axillary lymph nodes and by the size of the primary tumor. The sensitivity and specificity of ultrasound-guided FNA were calculated with axillary surgery as the reference standard. The sensitivity and specificity of axillary ultrasound to predict the ultrasound-guided FNA result were calculated. RESULTS: Of the 224 patients, 51 patients (23%) had a positive ultrasound-guided FNA result, which yields an overall sensitivity of 59% and specificity of 100%. The sensitivity of ultrasound-guided FNA was 29% in patients with primary tumors ≤ 1 cm, 50% in patients with tumors > 1 to ≤ 2 cm, 69% in patients with tumors > 2 to ≤ 5 cm, and 100% in patients with tumors > 5 cm. The sensitivity of ultrasound-guided FNA in patients with normal-appearing lymph nodes was 11%; indeterminate lymph nodes, 44%; and suspicious lymph nodes, 93%. Sonographic characterization of lymph nodes as suspicious or indeterminate was 94% sensitive and 72% specific in predicting positive findings at ultrasound-guided FNA. CONCLUSION: Ultrasound-guided FNA of the axillary lymph nodes is most useful in the preoperative assessment of patients with large tumors (> 2 cm) or lymph nodes that appear abnormal.

Epidermotropic Merkel cell carcinoma: a case series with histopathologic examination.

BACKGROUND: Merkel cell carcinoma (MCC), an aggressive malignancy that has been increasing in incidence, rarely presents with an epidermotropic pattern. OBJECTIVE: We conducted an immunohistochemical evaluation of 6 previously unpublished cases of epidermotropic MCC, focusing particularly on the staining characteristics of epithelial membrane antigen and cytokeratin-20 in the hope of providing insight into the mechanism of epidermotropism in MCC. METHODS: This study is a retrospective evaluation using light microscopy and immunohistochemistry. RESULTS: Forty cases of MCC with pathology at Rhode Island Hospital and the Miriam Hospital in Providence, RI, from 1983 through 2009 were reviewed. Following exclusion criteria, 6 patients (5 men, 1 woman) with a mean age of 82.5 years (range, 72-92) demonstrated epidermotropism. Three of 6 patients had MCC of the eyelid. In cases 1, 3, and 6, the perinuclear dot pattern observed with cytokeratin-20 in the epidermotropic MCC cells was less pronounced than the pattern observed in the dermis, and in all 6 of the tumors, the epidermal staining pattern observed with epithelial membrane antigen was not more or less prominent than the staining observed in the dermis. LIMITATIONS: The small total number of cases of epidermotropic MCC is a limitation. CONCLUSION: The data presented reinforce the differential diagnosis of tumors with an epidermotropic growth pattern and the importance of immunohistochemical staining in the histologic workup of such tumors: squamous cell carcinoma in situ, melanoma, mycosis fungoides, eccrine porocarcinoma, sebaceous carcinoma of the eyelid, mammary and extramammary Paget disease, MCC, and epidermotropic metastases. It is notable that 3 of 6 identified tumors were located on the eyelid; further study of epidermotropic MCC may shed more light on this finding, either as an unusual coincidence or a finding with unexplained significance.

Notch2 signaling induces apoptosis and inhibits human MDA-MB-231 xenograft growth.

Notch functions as an oncogene or tumor inhibitor in various cancers, and decreases in Notch2 expression are associated with increasing grade of human breast cancer. We constitutively activated Notch signaling with intracellular domain (ICD) expression in the human adenocarcinoma line MDA-MB-231. Notch2 signaling increased apoptosis, whereas Notch4ICD (int3) significantly increased cell proliferation and growth. Cells with activated Notch2 or Notch4 were injected into nu/nu mice for analysis of in vivo tumor xenograft phenotype. Tumor growth was significantly altered depending on the receptor activated. Notch2ICD potently suppressed tumor take and growth, leading to a 60% decrease in tumors and significantly smaller, necrotic tumors. Despite this, Notch2ICD tumors were highly vascularized, although the vessels were smaller and comprised a more immature network compared with Notch4ICD tumors. Notch4ICD tumors were highly aggressive and well vascularized, indicating a role for Notch4 signaling in the promotion of the malignant phenotype in addition to its transforming ability. Although both NotchICD groups expressed angiogenic factors, Notch4ICD had selective vascular endothelial growth factor-D in both tumor and host stroma, suggesting a differential regulation of cytokines that may impact vascular recruitment and autocrine tumor signaling. Our results demonstrate that Notch2 signaling is a potent inhibitory signal in human breast cancer xenografts.