A practical guide to managing CT findings in the breast.

While it is well accepted that CT is not an optimal imaging study to evaluate the breasts, findings on chest CT may be the first indication of an occult malignancy. The nonspecific appearance of breast findings and the lack of consensus guidelines for managing incidental breast findings may dissuade radiologists from thoroughly evaluating the breasts on CT. We review commonly encountered breast findings on CT and present an algorithm for managing incidentally detected breast findings.

Early Results From the Implementation of a Lung Cancer Screening Program: The Beaumont Health System Experience.

PURPOSE: In 2010, a new study published by the National Lung Screening Trial showed a 20% reduction in mortality for those patients screened with low-dose computed topography (CT) versus x-ray. Recently, the Centers of Medicare and Medicaid have agreed to cover this service for those patients who meet the screening criteria. We compare the outcomes and costs associated with developing and implementing a lung cancer screening program. MATERIALS AND METHODS: One thousand sixty-five patients were screened from January 2014 to December 2014. These patients were screened on a low-dose CT screening protocol throughout Beaumont Health System. The American College of Radiology Lung Imaging Reporting and Data System (Lung-RADS) were used to assign the score for each patient. Screening eligibility criteria were based on the National Comprehensive Cancer Network guidelines. Downstream activity and revenue was determined after initial low-dose CT screening. RESULTS: At 1 year, 20 patients (1.6%) were diagnosed with lung cancer and another 15 patients were diagnosed with another form of cancer after screening. The median age, packs per day, and pack years smoked for all patients was 63, 1.0, and 39.0 years, respectively. Lung-RADS scores for all patients was 18% (1), 24.1% (2), 6.3% (3), and 5.4% (4). The net revenue for all activity after screening was $3.2 million. CONCLUSIONS: The establishment of a low-dose CT lung cancer screening program improved the ability to screen patients as demonstrated by the number of patients screened and those diagnosed with a malignancy. These findings were also consistent with the findings from the National Lung Screening Trial study.

MRI for appendicitis in pregnancy: is seeing believing? clinical outcomes in cases of appendix nonvisualization.

PURPOSE: The primary objective of this study was to determine the clinical outcomes in cases of appendix nonvisualization with MRI in pregnant patients with suspected appendicitis and the implications of appendix nonvisualization for excluding appendicitis. METHODS: Fifty-eight pregnant patients with suspected appendicitis evaluated with MRI at three centers from a single institution were retrospectively reviewed by three radiologists with varying levels of abdominal imaging experience. All scans were performed on a 1.5-Tesla Siemens unit. Cases were evaluated for diagnostic quality, visualization of the appendix, presence of appendicitis, and alternate diagnoses. Clinical outcomes were gathered from the electronic medical record. RESULTS: Of the 58 patients who underwent MRI for suspected appendicitis, 50 cases were considered adequate diagnostic quality by all three radiologists. The rate of appendix visualization among the three radiologists ranged from 60 to 76% (p = 0.44). The appendix was nonvisualized by at least one of the three radiologists in 25 cases (50%). Of these, none had a final diagnosis of appendicitis including one patient who underwent appendectomy. MRI suggested an alternate diagnosis in 6 (24%) patients with appendix nonvisualization. For the three reviewers, the agreement level on whether or not the appendix was visualized on the MRI had a Light's kappa value of 0.526, indicating a "moderate" level of agreement (p value < 0.01). CONCLUSION: Despite only moderate level of interobserver agreement for appendix visualization, appendix nonvisualization on MRI in pregnant patients with suspected appendicitis confers a significant reduction in the risk of appendicitis compared to all comers as long as the study is adequate diagnostic quality and there are no secondary signs of appendicitis present.

Vitreomacular traction syndrome: postoperative functional and anatomic outcomes.

BACKGROUND AND OBJECTIVE: To analyze a variety of vitreomacular traction (VMT) morphologies to establish a major classification that better reflects the preoperative predictive factors of postoperative visual and anatomic outcomes. PATIENTS AND METHODS: Thirty-six eyes submitted to vitrectomy surgery were categorized with a VMT pattern (V- or J-shaped) and diameter (focal < 1,500 µm or broad > 1,500 µm) based on optical coherence tomography. RESULTS: The researchers compared different classifications of VMT. Despite similar postoperative best corrected visual acuity (BCVA) values (P = .393), cases with focal VMT had greater visual improvement (P = .027) because the preoperative BCVA was significantly lower in the focal group (P = .007). However, the BCVA improvements did not differ between the groups regarding the classic VMT morphologic patterns (P = .235). CONCLUSION: Postoperative outcomes and macular disorders are closely related to VMT size. The adhesion diameter (focal or broad VMT) and not the classic VMT morphologic pattern (V- or J-shaped) may better predict the postoperative anatomic and functional outcomes.

The role of saline flush injection rate in displacement of CT-injectable peripherally inserted central catheter tip during power injection of contrast material.

OBJECTIVE: The purpose of this article is to determine the rate and the cause of displacement of CT power-injectable peripherally inserted central catheters (CT-PICCs) during contrast material and saline flush injection and to modify CT-scanning protocols to decrease the frequency of displacement. MATERIALS AND METHODS: In the laboratory setting, in vitro modeling of CTPICC displacement during power injection was examined while varying the initial rate of injection of the saline flush. In the clinical setting, the CT images of all patients at a large academic hospital for one calendar year who underwent power injection of CT contrast media were reviewed for CT-PICC displacement. A retrospective comparison of the rate of displacement during the 8 months before implementing a protocol with a lower initial rate of saline flush and the rate of displacement for the 4 months after the protocol change was performed. RESULTS: Laboratory modeling showed dramatic movement of the CT-PICC at higher rates of saline flush. This movement was attributed to differences in viscosity between contrast media and saline. The clinical arm of the study found that 8.2% of the 243 examinations performed before implementing the new protocol resulted in displacement, in comparison with 2.2% of the 138 examinations performed afterward. This difference was considered statistically significant (p = 0.023). CONCLUSION: Initiation of saline flush at high injection rates correlates with a higher rate of CT-PICC displacement. The use of a slower initial rate of saline flush injection significantly reduces the rate of displacement.

Shielding artificially increases the attenuation of water: study of CT gradient attenuation induced by shielding (CT GAINS).

RATIONALE AND OBJECTIVES: Quantitatively analyze the computed tomography (CT) attenuation effects caused by bismuth shields, which are used to reduce superficial organ dose. MATERIALS AND METHODS: The solid water uniformity section of the American College of Radiology CT phantom was scanned with a modified chest CT protocol. Scans were performed with a bismuth breast shield in multiple configurations, emphasizing three clinically relevant orientations. Attenuation effects were measured as changes in mean Hounsfield unit (HU) values of equal midsagittal regions of interest (ROI). Multiple statistical techniques were used in regression analysis. RESULTS: Bismuth shielding resulted in significant positive shifts of the expected Hounsfield unit values. The mean nonshielded CT attenuation was -0.16 ± 0.75 HU. Based on the clinically relevant ROI distance from the shield (~3-16 cm), the shielded values ranged from 43.8-4 HU, 45.8-10.1 HU, and 50.6-4.5 HU for shields 1, 2, and 3, respectively. All shield configurations displayed a statistically significant shift (P < .0001) at all distance ranges. The best fitting regression model was a quadratic function of distance versus logarithmic function of HU. A prediction table of the approximate shift in water HU values as a function of ROI distance from the shield was generated per shield type from their respective close-fitting regressions. CONCLUSIONS: The data support the claim that bismuth shields increase the attenuation of water, which can cause inaccurate characterization of simple fluid, giving the appearance of complex fluid or even solid density. However, there is potential for anticipation of the attenuation effects to validate continued use of these shields for dose reduction.

Three-year safety and visual acuity results of epimacular 90 strontium/90 yttrium brachytherapy with bevacizumab for the treatment of subfoveal choroidal neovascularization secondary to age-related macular degeneration.

PURPOSE: To evaluate the long-term safety and visual acuity outcomes associated with epimacular strontium 90 brachytherapy combined with intravitreal bevacizumab for the treatment of subfoveal choroidal neovascularization because of age-related macular degeneration. METHODS: Thirty-four treatment-naive patients with predominantly classic, minimally classic, and occult subfoveal choroidal neovascularization lesions participated in this prospective, 2-year, nonrandomized multicenter study. Subjects from 1 center (n = 19) were reconsented and followed-up for 3 years. Each subject received a single 24-Gy beta irradiation treatment via an intraocular delivery device and 2 planned injections of bevacizumab at treatment and 1 month later. Additional bevacizumab therapy was permitted based on prespecified retreatment criteria. Adverse events were observed, and best-corrected visual acuity was measured using Early Treatment Diabetic Retinopathy Study vision charts. Subjects were evaluated every 3 months during the first year of follow-up and every 6 months during Years 2 and 3 of follow-up. RESULTS: All 34 subjects were followed-up for 24 months and 19 were followed-up through 36 months. With up to 24 months of follow-up, 12 of 24 phakic patients (50%) exhibited ≥ 2 grades of progression in Lens Opacification Classification System (LOCS) II lens classification; 5 eyes underwent cataract extraction before the Month 36 visit. There was 1 case of nonproliferative retinopathy identified at 36 months of follow-up that did not have an adverse effect on visual acuity, was stable at 43 months of follow-up, and was isolated to the parafoveal region. Mean best-corrected visual acuity demonstrated an average gain of +15.0 and -4.9 letters at 12 months and 24 months, respectively; the drop in mean gain at Month 24 was largely attributable to cataract formation. At 36 months (n = 19), the mean best-corrected visual acuity was +3.9, 90% (17 of 19) of eyes had lost <15 letters from baseline, 53% (10 of 19) had gained ≥ 1 letter, and 21% (4 of 19) had gained ≥ 15 letters. Through 36 months, 11 eyes required additional bevacizumab retreatment therapy and received a mean of 3.0 injections (range, 2-7 injections). CONCLUSION: Epimacular brachytherapy shows promise as a therapeutic option for subfoveal neovascular age-related macular degeneration. The procedure was safe and well tolerated, with a reasonable risk-benefit profile that warrants further study in larger subject populations. The most common adverse event was cataract progression/formation. Surgical complications are similar to those expected from standard vitrectomy trials. This novel device is currently being evaluated in two prospective, randomized, controlled trials in treatment-naive subjects (CABERNET) and in subjects already treated with anti-vascular endothelial growth factor therapy (MERLOT).

A comprehensive approach to CT radiation dose reduction: one institution's experience.

OBJECTIVE: The purpose of this article is to review the process of creating and implementing a comprehensive plan to reduce diagnostic radiation exposure at our institution. CONCLUSION: This process, which was initiated by forming a radiation dose reduction committee, addressed several different issues to improve patient safety. These include avoidance of unnecessary CT examinations, adjusting individual scanning parameters, revising protocols, use of shielding and dose monitoring, and implementing computer-based dose modulation software as well as educating referring physicians and radiologic technologists.