Reproducibility of Computer-Aided Detection Marks in Digital Mammography

OBJECTIVE: To evaluate the performance and reproducibility of a computeraided detection (CAD) system in mediolateral oblique (MLO) digital mammograms taken serially, without release of breast compression. MATERIALS AND METHODS: A CAD system was applied preoperatively to the fullfield digital mammograms of two MLO views taken without release of breast compression in 82 patients (age range: 33-83 years; mean age: 49 years) with previously diagnosed breast cancers. The total number of visible lesion components in 82 patients was 101: 66 masses and 35 microcalcifications. We analyzed the sensitivity and reproducibility of the CAD marks. RESULTS: The sensitivity of the CAD system for first MLO views was 71% (47/66) for masses and 80% (28/35) for microcalcifications. The sensitivity of the CAD system for second MLO views was 68% (45/66) for masses and 17% (6/35) for microcalcifications. In 84 ipsilateral serial MLO image sets (two patients had bilateral cancers), identical images, regardless of the existence of CAD marks, were obtained for 35% (29/84) and identical images with CAD marks were obtained for 29% (23/78). Identical images, regardless of the existence of CAD marks, for contralateral MLO images were 65% (52/80) and identical images with CAD marks were obtained for 28% (11/39). The reproducibility of CAD marks for the true positive masses in serial MLO views was 84% (42/50) and that for the true positive microcalcifications was 0% (0/34). CONCLUSION: The CAD system in digital mammograms showed a high sensitivity for detecting masses and microcalcifications. However, reproducibility of microcalcification marks was very low in MLO views taken serially without release of breast compression. Minute positional change and patient movement can alter the images and result in a significant effect on the algorithm utilized by the CAD for detecting microcalcifications

Sonographically-Guided 14-Gauge Core Needle Biopsy for Papillary Lesions of the Breast

OBJECTIVE: We wanted to assess the need for surgical excising papillary lesions of the breast that were diagnosed upon sonographically guided 14-gauge core needle biopsy. MATERIALS AND METHODS: Sixty-nine women (age range: 25-74 years, mean age: 51.7 years) with 69 papillary lesions (4.9%) were diagnosed and followed after performing sonographically guided 14-gauge core needle biopsies. Surgical excision was performed for 44 (64%) of 69 papillary lesions, and 25 lesions were followed with imaging studies (range: 6-46 months, mean: 17.9 months). The histologic findings upon core biopsy were compared with the surgical, imaging and follow-up findings. RESULTS: Core needle biopsies of 69 lesions yielded tissue that was classified as benign for 43 lesions, atypical for 18 lesions and malignant for eight lesions. Of the 43 lesions that yielded benign papilloma upon core needle biopsy, one had intraductal papillary carcinoma found upon surgery. An immediate surgical biopsy was recommended for this lesion because of the imaging-histologic discordance. No additional carcinoma was found during the imaging follow-up. Surgical excision was performed for 17 atypical papillary lesions, and this revealed intraductal (n = 6) or invasive (n = 2) papillary carcinoma in 8 (47%) lesions. Of the seven intraductal papillary carcinomas, surgery revealed invasive papillary carcinoma in one (14%). CONCLUSION: Our results suggest that papillary lesions of the breast that are diagnosed as benign upon sonographically guided 14-gauge core needle biopsy can be followed when the results are concordant with the imaging findings

Strategies for assessing renal function prior to outpatient contrast-enhanced CT: a UK survey

YesThe purpose of this paper is to identify current UK screening practices prior to contrast-enhanced CT. To determine the patient management strategies to minimize the risk of contrast-induced acute kidney injury (CI-AKI) risk in outpatients. An invitation to complete an electronic survey was distributed to the CT managers of 174 UK adult National Health Service hospital trusts. The survey included questions related to local protocols and national guidance on which these are based. Details of the assessment of renal function prior to imaging and thresholds for contrast contraindication and patient management were also sought. A response rate of 47.1% was received. Almost all sites had a policy in place for contrast administration (n = 80/82; 97.6%). The majority of sites require a blood test on outpatients undergoing a contrast-enhanced CT scan (n = 75/82; 91.5%); however, some (15/75; 20.0%) sites only check the result in patients at high risk and a small number (7/82; 8.5%) of sites indicated that it was a referrer responsibility. The estimated glomerular filtration rate (eGFR) or serum creatinine (SCr) result threshold at which i.v. contrast was contraindicated varied and 19 different threshold levels of eGFR or SCr were identified, each leading to different prophylactic strategies. Inconsistency was noted in the provision of follow-up blood tests after contrast administration. The wide variation in practice reflects inconsistencies in published guidance. Evidence-based consensuses of which patients to test and subsequent risk thresholds will aid clinicians identify those patients in which the risk of CI-AKI is clinically significant but manageable. There is also a need to determine the value of the various prophylactic strategies, follow-up regimen and efficient service delivery pathways. This survey has identified that further work is required to define which patients are high risk, confirm those which require renal function testing prior to contrast administration and how best to manage patients at risk of CI-AKI. The role of new technologies within this service delivery pathway requires further investigation

Diagnosing fibrotic lung disease: When is high-resolution computed tomography sufficient to make a diagnosis of idiopathic pulmonary fibrosis?

Idiopathic pulmonary fibrosis (IPF), a progressive and fatal diffuse parenchymal lung disease, is defined pathologically by the pattern of usual interstitial pneumonia (UIP). Unfortunately, a surgical lung biopsy cannot be performed in all patients due to comorbidities that may significantly increase the morbidity and mortality of the procedure. High-resolution computed tomography (HRCT) has been put forth as a surrogate to recognize pathological UIP. The quality of the HRCT impacts the ability to make a diagnosis of UIP and varies based on the centre performing the study and patient factors. The evaluation of the HRCT includes assessing the distribution and predominance of key radiographical findings, such as honeycomb, septal thickening, traction bronchiectasis and ground glass attenuation lesions. The combination of the pattern and distribution is what leads to a diagnosis and associated confidence level. HRCT features of definite UIP (subpleural, basal predominant honeycomb with septal thickening, traction bronchiectasis and ground glass attenuation lesions) have a high specificity for the UIP pathological pattern. In such cases, surgical lung biopsy can be avoided. There are caveats to using the HRCT to diagnose IPF in isolation as a variety of chronic pulmonary interstitial diseases may progress to a UIP pattern. Referral centres with experience in diffuse parenchymal lung disease that have multidisciplinary teams encompassing clinicians, radiologists and pathologists have the highest level of agreement in diagnosing IPF.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75246/1/j.1440-1843.2009.01626.x.pd

Medical physics staffing for radiation oncology: a decade of experience in Ontario, Canada.

The January 2010 articles in The New York Times generated intense focus on patient safety in radiation treatment, with physics staffing identified frequently as a critical factor for consistent quality assurance. The purpose of this work is to review our experience with medical physics staffing, and to propose a transparent and flexible staffing algorithm for general use. Guided by documented times required per routine procedure, we have developed a robust algorithm to estimate physics staffing needs according to center-specific workload for medical physicists and associated support staff, in a manner we believe is adaptable to an evolving radiotherapy practice. We calculate requirements for each staffing type based on caseload, equipment inventory, quality assurance, educational programs, and administration. Average per-case staffing ratios were also determined for larger-scale human resource planning and used to model staffing needs for Ontario, Canada over the next 10 years. The workload specific algorithm was tested through a survey of Canadian cancer centers. For center-specific human resource planning, we propose a grid of coefficients addressing specific workload factors for each staff group. For larger scale forecasting of human resource requirements, values of 260, 700, 300, 600, 1200, and 2000 treated cases per full-time equivalent (FTE) were determined for medical physicists, physics assistants, dosimetrists, electronics technologists, mechanical technologists, and information technology specialists, respectively

Early diagnosis of brain tumours using a novel spectroscopic liquid biopsy

Early diagnosis of brain tumours is challenging and a major unmet need. Patients with brain tumours most often present with non-specific symptoms more commonly associated with less serious diagnoses, making it difficult to determine which patients to priortitise for brain imaging. Delays in diagnosis affect timely access to treatment, with potential impacts on quality of life and survival. A test to help identify which patients with non-specific symptoms are most likely to have a brain tumour at an earlier stage would dramatically impact on patients by prioritising demand on diagnostic imaging facilities. This clinical feasibility study of brain tumour early diagnosis was aimed at determining the accuracy of our novel spectroscopic liquid biopsy test for the triage of patients with non-specific symptoms that might be indicative of a brain tumour, for brain imaging. Patients with a suspected brain tumour based on assesement of their symptoms in primary care can be referred for open access CT scanning. Blood samples were prospectively obtained from 385 of such patients, or patients with a new brain tumour diagnosis. Samples were analysed using our spectroscopic liquid biopsy test to predict presence of disease, blinded to the brain imaging findings. The results were compared to the patient’s index brain imaging delivered as per standard care. Our test predicted the presence of glioblastoma, the most common and aggressive brain tumour, with 91% sensitivity, and all brain tumours with 81% sensitivity, and 80% specificity. Negative predictive value was 95% and positive predictive value 45%. The reported levels of diagnostic accuracy presented here have the potential to improve current symptom-based referral guidelines, and streamline assessment and diagnosis of symptomatic patients with a suspected brain tumour

Nonpalpable Breast Masses: Evaluation by US Elastography

OBJECTIVE: To compare the diagnostic performances of conventional ultrasound (US) and US elastography for the differentiation of nonpalpable breast masses, and to evaluate whether elastography is helpful at reducing the number of benign biopsies, using histological analysis as a reference standard. MATERIALS AND METHODS: Conventional US and real-time elastographic images were obtained for 100 women who had been scheduled for a US-guided core biopsy of 100 nonpalpable breast masses (83 benign, 17 malignant). Two experienced radiologists unaware of the biopsy and clinical findings analyzed conventional US and elastographic images by consensus, and classified lesions based on degree of suspicion regarding the probability of malignancy. Results were evaluated by receiver operating characteristic curve analysis. In addition, the authors investigated whether a subset of lesions was categorized as suspicious by conventional US, but as benign by elastography. RESULTS: Areas under the ROC curves (Az values) were 0.901 for conventional US and 0.916 for elastography (p = 0.808). For BI-RADS category 4a lesions, 44% (22 of 50) had an elasticity score of 1 and all were found to be benign. CONCLUSION: Elastography was found to have a diagnostic performance comparable to that of conventional US for the differentiation of nonpalpable breast masses. The authors conclude that BI-RADS category 4a lesions with an elasticity score of 1 probably do not require biopsy