Improvement in Follow-up Imaging With a Patient Tracking System and Computerized Registry for Lung Nodule Management

PurposeDespite established guidelines, radiologists’ recommendations and timely follow-up of incidental lung nodules remain variable. To improve follow-up of nodules, a system using standardized language (tracker phrases) recommending time-based follow-up in chest CT reports, coupled with a computerized registry, was created.Materials and MethodsData were obtained from the electronic health record and a facility-built electronic lung nodule registry. We evaluated two randomly selected patient cohorts with incidental nodules on chest CT reports: before intervention (September 2008 to March 2011) and after intervention (August 2011 to December 2016). Multivariable logistic regression was used to compare the cohorts for the main outcome of timely follow-up, defined as a subsequent report within 13 months of the initial report.ResultsIn all, 410 patients were included in the pretracker cohort versus 626 in the tracker cohort. Before system inception, 30% of CT reports lacked an explicit time-based recommendation for nodule follow-up. The proportion of patients with timely follow-up increased from 46% to 55%, and the proportion of those with no documented follow-up or follow-up beyond 24 months decreased from 48% to 31%. The likelihood of timely follow-up increased 41%, adjusted for high risk for lung cancer and age 65 years or older. After system inception, reports missing a tracker phrase for nodule recommendation averaged 6%, without significant interyear variation.ConclusionsStandardized language added to CT reports combined with a computerized registry designed to identify and track patients with incidental lung nodules was associated with improved likelihood of follow-up imaging.     

Recommendations for additional imaging on emergency department CT examinations: comparison of emergency- and organ-based subspecialty radiologists

Purpose

Past studies have identified a high frequency of recommendations for additional imaging (RAI) for computed tomography (CT) studies performed in an emergency department (ED), thereby potentially contributing to increased imaging utilization and costs. The purpose of this study was to compare rates of RAI within the ED setting between ED-based and organ-based subspecialty radiologists.

Methods

We identified 600 ED CT studies, comprising 200 head, chest, and abdominal CT studies, split equally between cases reviewed by ED-based and organ-based radiologists. Frequency of RAI for the three examinations was compared between these subspecialty groups.

Results

Frequencies of RAI were 21.5 %, 13.5 %, and 5.5 % for CT examinations of the chest, abdomen, and brain, respectively. There was a significantly higher frequency of RAI for chest CT studies interpreted by chest radiologists than by ED radiologists (28.0 % vs. 15.0 %, respectively, p?=?0.036), largely due to a higher rate of RAI for incidentally detected lung nodules and masses as well as other pulmonary parenchymal abnormalities by chest radiologists. There was no significant difference in RAI on brain or abdominal CT studies between the two groups (p?=?0.426–1.0). However, on abdominal studies, only ED-based radiologists provided RAI for abnormalities of the bowel or uterus, while only organ-based radiologists provided RAI for pancreatic abnormalities. Only 25.6 % of RAI were subsequently performed at our institution.

Conclusion

For chest CT studies performed at the authors' institution, differences in management of incidental pulmonary nodules contributed to a significantly higher frequency of RAI by chest radiologists than by ED-based radiologists. Further investigation of the impact of these differences on cost and patient outcomes is warranted.     

计算机辅助检测肺结节在数字化X线胸片肺癌筛查中的应用价值

目的 评价计算机辅助检测(CAD)肺结节系统在数字化X线胸片上肺癌筛查中的应用价值.方法 由1名放射科医师和CAD肺结节检测系统独立阅读100例连续的数字摄影(DR)X线胸片,CAD系统可以检出最长直径在5～15 mm的肺结节.由2名放射科专家(有15年胸部影像诊断经验)进行回顾性阅读,参照相应的CT图像,两人意见达成一致后标记真结节的个数和位置并保存标记结果,将标记结果作为金标准来比较放射科医师和CAD系统的肺结节检测敏感性和假阳性率.结果 放射科医师共检测到95个结节,CAD系统共检测到304个结节.在回顾性检查中2名放射科专家共标记134个真结节,其中放射科医师检测到82个(61.2%),CAD检测到105个(78.4%),CAD系统检测到而被放射科医师漏诊的结节35个,放射科医师检测到而CAD系统漏诊的结节10个.放射科医师应用CAD系统后检测到112个真结节,检测率提高到83.6%.放射科专家意见一致后认为CAD系统检出199个假阳性结节,平均每张胸片约2.0个.结论 在肺癌筛查中放射科医师和CAD系统必须联合应用才可以识别X线胸片中所有的结节.     

Digital synthesis of lung nodules

Studies evaluating observer accuracy and visual perception of pulmonary nodules usually are based upon test films obtained from clinical practice in patients with proven pulmonary nodules. Unfortunately, such nodules do not always occur in the optimal size and location to facilitate testing. Such studies would be enhanced by the ability to place nodules of desired size and location on chest radiographs. This report describes a method of placing a computer-generated (synthesized) nodule on a digitized chest radiograph. To demonstrate the similarity of these synthesized nodules to real nodules, each digitized radiograph with a computer-generated nodule was paired with a digitized chest radiograph of a patient with a clinically proven pulmonary nodule. A total of 22 pairs of chest radiographs were then shown to 13 radiologists, who were asked to distinguish the synthesized nodule from the real nodule. With this two alternative forced-choice test, the radiologists were only able to distinguish the synthesized nodule in 51% of the cases, strongly suggesting that computer generated nodules may be used to simulate real pulmonary nodules in future tests of nodule detection.     

Radiologist Point-of-Care Clinical Decision Support and Adherence to Guidelines for Incidental Lung Nodules

PurposeTo evaluate the effect of a workstation-integrated, point-of-care, clinical decision support (CDS) tool on radiologist adherence to radiology department guidelines for follow-up of incidental pulmonary nodules detected on abdominal CT.MethodsThe CDS tool was developed to facilitate adherence to department guidelines for managing pulmonary nodules seen on abdominal CT. In October 2012, the tool was deployed within the radiology department of an academic medical center and could be used for a given abdominal CT at the discretion of the interpreting radiologist. We retrospectively identified consecutive patients who underwent abdominal CT (in the period from January 2012 to April 2013), had no comparison CT scans available, and were reported to have a solid, noncalcified, pulmonary nodule. Concordance between radiologist follow-up recommendation and department guidelines was compared among three groups: patients scanned before implementation of the CDS tool; and patients scanned after implementation, with versus without use of the tool.ResultsA total of 409 patients were identified, including 268 for the control group. Overall, guideline concordance was higher after CDS tool implementation (92 of 141 [65%] versus 133 of 268 [50%], P = .003). This finding was driven by the subset of post-CDS implementation cases in which the CDS tool was used (57 of 141 [40%]). In these cases, guideline concordance was significantly higher (54 of 57 [95%]), compared with post-implementation cases in which CDS was not used (38 of 84 [45%], P < .001), and to a control group of patients from before implementation (133 of 268 [50%]; P < .001).ConclusionsA point-of-care CDS tool was associated with improved adherence to guidelines for follow-up of incidental pulmonary nodules.     

Radiology Reports for Incidental Thyroid Nodules on CT and MRI: High Variability across Subspecialties

BACKGROUND AND PURPOSE:Variability in radiologists'' reporting styles and recommendations for incidental thyroid nodules can lead to confusion among clinicians and may contribute to inconsistent patient care. Our aim was to describe reporting practices of radiologists for incidental thyroid nodules seen on CT and MR imaging and to determine factors that influence reporting styles.MATERIALS AND METHODS:This is a retrospective study of patients with incidental thyroid nodules reported on CT and MR imaging between January and December 2011, identified by text search for “thyroid nodule” in all CT and MR imaging reports. The studies included CT and MR imaging scans of the neck, spine, and chest. Radiology reports were divided into those that mentioned the incidental thyroid nodules only in the “Findings” section versus those that reported the incidental thyroid nodules in the “Impression” section as well, because this latter reporting style gives more emphasis to the finding. Univariate and multivariate analyses were performed to identify radiologist, patient, and nodule characteristics that influenced reporting styles.RESULTS:Three hundred seventy-five patients met the criterion of having incidental thyroid nodules. One hundred thirty-eight (37%) patients had incidental thyroid nodules reported in the “Impression” section. On multivariate analysis, only radiologists'' divisions and nodule size were associated with reporting in “Impression.” Chest radiologists and neuroradiologists were more likely to report incidental thyroid nodules in the “Impression” section than their abdominal imaging colleagues, and larger incidental thyroid nodules were more likely to be reported in “Impression” (P ≤ .03). Seventy-three percent of patients with incidental thyroid nodules of ≥20 mm were reported in the “Impression” section, but higher variability in reporting was seen for incidental thyroid nodules measuring 10–14 mm and 15–19 mm, which were reported in “Impression” for 61% and 50% of patients, respectively.CONCLUSIONS:Reporting practices for incidental thyroid nodules detected on CT and MR imaging are predominantly influenced by nodule size and the radiologist''s subspecialty. Reporting was highly variable for nodules measuring 10–19 mm; this finding can be partially attributed to different reporting styles among radiology subspecialty divisions. The variability demonstrated in this study further underscores the need to develop CT and MR imaging practice guidelines with the goal of standardizing reporting of incidental thyroid nodules and thereby potentially improving the consistency and quality of patient care.

Incidental thyroid nodules (ITNs) are a common radiologic finding, seen in 1 in 6 patients undergoing CT and MR imaging examinations of the neck.^1,2 Unlike nodules seen on sonography, there are no reliable signs of malignancy and no well-accepted guidelines for reporting ITNs detected on CT and MR imaging. Consequently, the current practice of reporting thyroid nodules on CT and MR imaging by radiologists is highly variable.³ Some radiologists may report all ITNs because there is a chance that an ITN could be malignant. Other radiologists may not report any ITNs because thyroid cancers in ITNs are relatively uncommon⁴ and small thyroid cancers often have an indolent course.^5,6 In particular, reporting an ITN in the “Impression” section of a radiology report provides more emphasis of the finding and may increase the chance of further work-up.Different recommendations for patients with the same nodule characteristics and clinical history are problematic because they can lead to variation in practice patterns, potential variation in the quality of patient care, and anxiety for patients, and they can potentially increase health care costs from the performance of more imaging studies, biopsies, and diagnostic surgeries.^2,7–9 Although some incidental cancers may be diagnosed and treated at an earlier stage, >50% of patients with ITNs that have surgery will ultimately be diagnosed with benign disease.^10,11The variation in reporting styles for ITNs seen on CT and MR imaging has been measured in a recent study, which surveyed radiologists on how they reported different scenarios varying in nodule size and patient history.³ The study demonstrated high variability of ITN reporting, with an overall mean agreement in reporting style of 53% and lower rates of agreement for smaller nodules. A limitation of a survey, however, is that it may not accurately reflect what a radiologist actually does in practice. Another study evaluated reporting practices for ITNs based on radiology reports for cervical spine CT.¹² The authors found that recommendations for ITNs are made inconsistently and the type of management recommended is variable. However, variability in reporting may have been underestimated in their study because it was limited to CT reports issued only by emergency radiologists and did not encompass the reporting practices of abdominal, chest, and neuroimaging radiologists. In addition, the authors did not differentiate between ITNs reported in the “Impression” section of the report versus only the “Findings” section. To fully examine variability in reporting of ITNs, a study should evaluate the reporting style, encompass all radiology subspecialties, and include all CT and MR imaging studies that may lead to detection of ITNs.The purpose of this study was to describe the reporting practices of radiologists for ITNs seen on CT and MR imaging and to determine the factors associated with reporting ITNs in the “Impression” section of the radiology report. We hypothesized that reporting styles would be influenced not only by nodule and patient characteristics but also by radiologist-specific factors, such as subspecialty training and years of experience. Understanding factors associated with variation in reporting practices among radiologists may help to standardize practice patterns, and demonstration of highly variable practices would support the need for guidelines for reporting ITNs seen on CT and MR imaging.     

Evaluation of a real-time interactive pulmonary nodule analysis system on chest digital radiographic images: a prospective study

RATIONALE AND OBJECTIVES: We sought to assess the performance of a real-time interactive pulmonary nodule analysis system for evaluation of chest digital radiographic (DR) images in a routine clinical environment. MATERIALS AND METHODS: A real-time interactive pulmonary nodule analysis system for chest DR image softcopy reading (IQQA-Chest; EDDA Technology, Princeton Junction, NJ) was used in daily practice with a Picture Archiving and Communication System in a National Cancer Institute-designated cancer teaching hospital. Patients referred for follow-up of known cancer underwent digital chest radiography. Posteroanterior and lateral DR images were first read by resident radiologists along with experienced chest radiologists using a Picture Archiving and Communication System work station. The computer-assisted detection (CAD) program was subsequently applied to the posteroanterior DR images, and changes (if any) in diagnosis were recorded. For reference standard, a follow-up chest radiograph at least 6 months following the initial examination or a follow-up computed tomographic scan of the chest within 3 months was used to establish diagnostic accuracy. RESULTS: Of 324 DR examinations, follow-up imaging according to our parameters was available for 214 patients (67%). Lung nodules were found and subsequently confirmed in 35 patients (10%) without CAD. Using CAD, nodules were found and subsequently confirmed in 51 patients (15%), improving sensitivity from 63.8% (95% confidence interval [CI], 0.49%-0.76%) to 92.7% (95% CI, 0.82%-0.98%) (P < .0001, McNemar). Nodules were subsequently proved to be malignant in five of the 16 additional cases (31%). False-positive readings increased from three to six cases; specificity decreased from 98.1% (95% CI, 0.95%-0.99%) to 96.2% (95% CI, 0.92%-0.98%) (not significant). There were 153 true-negative cases (71.4%). CONCLUSIONS: This study suggests that the interpretation of chest radiographs for lung nodules can be improved using an automated CAD nodule detection system. This improvement in reader performance comes with a minimal number of false-positive interpretations.     

Natural Language Processing for Identification of Incidental Pulmonary Nodules in Radiology Reports

PurposeTo develop natural language processing (NLP) to identify incidental lung nodules (ILNs) in radiology reports for assessment of management recommendations.Methods and MaterialsWe searched the electronic health records for patients who underwent chest CT during 2014 and 2017, before and after implementation of a department-wide dictation macro of the Fleischner Society recommendations. We randomly selected 950 unstructured chest CT reports and reviewed manually for ILNs. An NLP tool was trained and validated against the manually reviewed set, for the task of automated detection of ILNs with exclusion of previously known or definitively benign nodules. For ILNs found in the training and validation sets, we assessed whether reported management recommendations agreed with Fleischner Society guidelines. The guideline concordance of management recommendations was compared between 2014 and 2017.ResultsThe NLP tool identified ILNs with sensitivity and specificity of 91.1% and 82.2%, respectively, in the validation set. Positive and negative predictive values were 59.7% and 97.0%. In reports of ILNs in the training and validation sets before versus after introduction of a Fleischner reporting macro, there was no difference in the proportion of reports with ILNs (108 of 500 [21.6%] versus 101 of 450 [22.4%]; P = .8), or in the proportion of reports with ILNs containing follow-up recommendations (75 of 108 [69.4%] versus 80 of 101 [79.2%]; P = .2]. Rates of recommendation guideline concordance were not significantly different before and after implementation of the standardized macro (52 of 75 [69.3%] versus 60 of 80 [75.0%]; P = .43).ConclusionNLP reliably automates identification of ILNs in unstructured reports, pertinent to quality improvement efforts for ILN management.     

Process Improvement for Communication and Follow-up of Incidental Lung Nodules

ObjectiveGuideline-concordant follow-up of incidental lung nodules (ILNs) is suboptimal. We aimed to improve communication and tracking for follow-up of these common incidental findings detected on imaging examinations.MethodsWe implemented a process improvement program for reporting and tracking ILNs at a large urban academic health care system. A multidisciplinary committee designed, tested, and implemented a multipart tracking system in the electronic health record (EHR) that included Fleischner Society management recommendations for each patient. Plan-do-study-act cycles addressed gaps in the follow-up of ILNs, broken into phases of developing and testing components of the conceived EHR toolkit.ResultsThe program resulted in standardized text macros with discrete categories and recommendations for ILNs, with ability to track each case in a work list within the EHR. The macros incorporated evidence-based guidelines and also input of collaborating clinical referrers in the respective specialty. The ILN macro was used 3,964 times over the first 2 years, increasing from 104 to over 300 uses per month. Usage spread across all subspecialty divisions, with nonthoracic radiologists currently accounting for 80% (56 of 70) of the radiologists using the system and 31% (1,230 of 3,964) of all captured ILNs. When radiologists indicated ILNs as warranting telephone communication to provider offices, completion was documented in 100% of the cases captured in the EHR-embedded tracking report.ConclusionAn EHR-based system for managing incidental nodules enables case tracking with exact recommendations, provider communication, and completion of follow-up testing. Future efforts will target consistent radiologist use of the system and follow-up completion.     

A review of staging chest CT in trunk and extremity soft tissue sarcoma

Objectives:To determine the incidence of pulmonary metastases on chest CT in trunk and extremity soft tissue sarcoma based on two size criteria, and to identify factors associated with metastases.Methods:Retrospective review of chest CT studies in patients with trunk and extremity soft tissue sarcoma over an 18-month period. Data collected included patient age/sex, tumour location, size and relationship to fascia. All chest CTs were reviewed for the presence of metastases which were diagnosed according to two size criteria: multiple nodules > 5 mm in size or multiple nodules > 10 mm in size. Follow-up CT studies were reviewed in cases initially considered indeterminate.Results:127 males and 73 females were included (mean age 57.1 years; range 10–90 years). 147 (73.5%) tumours were deep to the fascia and 53 (26.5%) superficial. Tumour size classified according to the 12 AJCC 2019 criteria was: T1 = 52, T2 = 76, T3 = 39, T4 = 33. Based on nodule size >5 mm, 73 (36.5%) patients had no metastases, 42 (21%) had metastases, while 85 (42.5%) studies were indeterminate. Based on nodule size >10 mm, 73 (36.5%) patients had no metastases, 28 (14%) had metastases, while 99 (49.5%) studies were indeterminate. Larger maximum dimension of the primary tumour was a risk factor for pulmonary metastases using both size criteria.Conclusion:The incidence of pulmonary metastases at presentation in trunk and extremity soft tissue sarcoma is 14–21%. 42.5–49.5% of chest CTs were indeterminate.Advances in knowledge:The incidence of pulmonary metastases at presentation in trunk and extremity soft tissue sarcoma is 14–21%. Indeterminate pulmonary nodules are also very common.     

Variation in Radiologists’ Follow-Up Imaging Recommendations for Small Cystic Pancreatic Lesions

ObjectiveThis study aimed to determine the incidence, identify imaging and patient factors, and measure individual radiologist variation associated with follow-up recommendations for small focal cystic pancreatic lesions (FCPLs), a common incidental imaging finding.MethodsThis institutional review board–approved retrospective study analyzed 146,709 reports from abdominal CTs and MRIs performed in a large academic hospital from July 1, 2016, to June 30, 2018. A trained natural language processing tool identified 4,345 reports with FCPLs, which were manually reviewed to identify those containing one or more <1.5-cm pancreatic cysts. For these patients, patient, lesion, and radiologist features and follow-up recommendations for FCPL were extracted. A nonlinear random-effects model estimated degree of variation in follow-up recommendations across radiologists at department and division levels.ResultsOf 2,872 reports with FCPLs < 1.5 cm, 708 (24.7%) had FCPL-related follow-up recommendations. Average patient age was 67 years (SD ± 11). In all, 1,721 (60.0%) reports were for female patients; 59.3% of patients had only one cyst. In multivariable analysis, older patients had slightly lower follow-up recommendation rates (odds ratio [OR]: 0.98 [0.98-1.00] per additional year), and lesions associated with main duct dilatation and septation were more likely to have a follow-up recommendation (ORs: 1.93 [1.11-3.36] and 2.88 [1.89-4.38], respectively). Radiologist years in practice (P = .51), trainee presence (P = .21), and radiologist gender (P = .52) were not associated with increased follow-up recommendations. There was significant interradiologist variation in the Abdominal Imaging Division (P = .04), but not in Emergency Radiology (P = .31) or Cancer Imaging Divisions (P = .29).DiscussionInterradiologist variation significantly contributes to variability in follow-up imaging recommendations for FCPLs.     

Retrospective Analysis of Emergency Computed Tomography Imaging Utilization at an Academic Centre: An Analysis of Clinical Indications and Outcomes

PurposeTo explore resource utilization through evaluation of computed tomography (CT) imaging trends in the emergency department by examining common indications/outcomes for imaging in this setting.MethodsA retrospective analysis of clinical indications/outcomes for all CT imaging in 3 emergency departments over a 1-year period was conducted. Scans were divided by body part and the most common indications for each type of scan were determined. Clinical outcomes from each study were extracted from final interpretations by the reporting radiologist.ResultsA total of 4556 CT scans were performed in the emergency department over a 1-year period. A total of 3.6% of all-comers to our emergency departments underwent CT scan as part of their investigation. There were 2107 head CTs (46%), 1296 (28%) abdominal CTs, 468 (10%) CTs of the chest, 408 (9%) CTs of the neck/spine, and 101 (2%) extremity CTs performed. The most common clinical indication for performing a CT head was focal neurological defect comprising 1534 (73%) of all CT heads. Twenty-four percent of abdominal CTs were for investigation of right lower quadrant pain, followed by flank pain (19%). Chest pain and shortness of breath were the most common indications for CTs of the chest (315 [75%]) with 10% of these examinations for this indication positive for pulmonary embolism. Trauma was the most common indication for neck CTs (296 [73%]) and extremities (70 [69%]). Nil acute was the most common final interpretation in all categories (79% CT heads, 75% neck CTs, 38% abdominal CTs, 43% chest CTs).ConclusionsNil acute was the most common diagnosis; however, serious clinical outcomes were identified 40% of the time. Cross-sectional imaging remains an integral tool for triage and diagnosis in this environment as the cost of missing a diagnosis in this setting has a great impact on patient care.     

Comparison of radiologist and CAD performance in the detection of CT-confirmed subtle pulmonary nodules on digital chest radiographs

OBJECTIVES: Detection of subtle pulmonary nodules on digital radiography is a challenging task for radiologists. The aim of this study was to evaluate the performance of a newly approved computer aided detection (CAD) system. MATERIALS AND METHODS: The sensitivity of 3 radiologists and of a CAD system for the detection of pulmonary nodules from 5 to 15 mm in size on digital chest radiography of 117 patients was compared. The reference standard was established by consensus reading of computed tomography scans by 2 experienced radiologists. Computed tomography scans and chest radiographs were performed within 4 weeks. Sixty-six pulmonary nodules from 42 patients, with a mean nodule diameter of 7.5 mm (standard deviation: 2.2 mm), were included in the statistical analysis. Seventy-five of the 117 patients did not have nodules from 5 to 15 mm of size. RESULTS: Two hundred and eighty-eight false-positive detections of the CAD system were found with an average of 2.5 false-positives per image. Sensitivity of the CAD system was 39.4% (95% confidence interval: 11.8%), when compared with 18.2% to 30.3% (95% confidence interval 9.3% to 11.1%) of the 3 radiologists. Substantial agreement for nodule detection ([kappa]N: 0.64-0.73) was found among the 3 radiologists, whereas only moderate agreement was found between the radiologists and the CAD performance ([kappa]N: 0.45-0.52). CONCLUSIONS: The CAD system's diagnostic sensitivity in detecting pulmonary nodules of 5 to 15 mm of size was superior to the 1 of radiologists. The CAD system may be used for assisting the radiologist in the detection of lung nodules on digital chest radiographs.     

Performance of computer-aided detection of pulmonary nodules in low-dose CT: comparison with double reading by nodule volume

Objective

To evaluate performance of computer-aided detection (CAD) beyond double reading for pulmonary nodules on low-dose computed tomography (CT) by nodule volume.

Methods

A total of 400 low-dose chest CT examinations were randomly selected from the NELSON lung cancer screening trial. CTs were evaluated by two independent readers and processed by CAD. A total of 1,667 findings marked by readers and/or CAD were evaluated by a consensus panel of expert chest radiologists. Performance was evaluated by calculating sensitivity of pulmonary nodule detection and number of false positives, by nodule characteristics and volume.

Results

According to the screening protocol, 90.9?% of the findings could be excluded from further evaluation, 49.2?% being small nodules (less than 50?mm³). Excluding small nodules reduced false-positive detections by CAD from 3.7 to 1.9 per examination. Of 151 findings that needed further evaluation, 33 (21.9?%) were detected by CAD only, one of them being diagnosed as lung cancer the following year. The sensitivity of nodule detection was 78.1?% for double reading and 96.7?% for CAD. A total of 69.7?% of nodules undetected by readers were attached nodules of which 78.3?% were vessel-attached.

Conclusions

CAD is valuable in lung cancer screening to improve sensitivity of pulmonary nodule detection beyond double reading, at a low false-positive rate when excluding small nodules.

Key Points

? Computer-aided detection (CAD) has known advantages for computed tomography (CT). ? Combined CAD/nodule size cut-off parameters assist CT lung cancer screening. ? This combination improves the sensitivity of pulmonary nodule detection by CT. ? It increases the positive predictive value for cancer detection.     

Integration of a Community Radiology Division into a Subspecialty-Focused Academic Radiology Department

IntroductionAssimilate a general radiology division into a subspecialty-focused radiology department at an academic medical center.MethodsThis Institutional Review Board-approved quality improvement initiative was performed at an academic medical centers’ subspecialty-focused academic radiology department, aiming to assimilate a general radiology division providing interpretive services for a distributed set of community ambulatory practices. An Oversight Committee charged by the department chair created a charter with unambiguous goal, timelines, clear decision-making, and conflict resolution processes. The Committee assessed the resources and clinical capabilities of the general radiologists, and the anticipated shift in exam volume from the community into subspecialty divisions. Primary outcome, percentage of targeted organ systems-specific interpretations by general radiologists based on assigned subspecialty division, and secondary outcome of report turnaround time (TAT) for all ambulatory exams, were compared before and after sub-specialization.ResultsAmong 10 general radiologists, 4.5 were assigned to subspecialty divisions; 5.5 continued to cover an independent general radiology practice in a for-profit delivery network. In the 5 months’ post-transition, a total 86.6% (11,668/13,477) of reports by the integrated general radiologists were within designated subspecialty divisions vs 23.9% (2,586/10,829) pre-transition (P < 0.01). There was no change in ambulatory radiology report TAT for non-urgent care center (UCC) or UCC exams pre- vs post-integration.DiscussionA quality improvement initiative with unambiguous decision-making and conflict resolution processes incorporated a general radiology practice (radiologists and exams) into a subspecialty-focused academic radiology practice without negatively impacting TAT metrics. Future studies would be needed to assess impact on quality of interpretations.     

Comparing Breast and Abdominal Subspecialists’ Follow-Up Recommendations for Incidental Liver Lesions on Breast MRI

PurposeThe aim of this study was to compare breast imaging subspecialists’ follow-up recommendations for incidental liver lesions (ILLs) on breast MRI with abdominal subspecialty radiologists’ opinions informed by best-practice recommendations.MethodsIn this retrospective study at an academic medical center, natural language processing identified reports with ILLs among 2,181 breast MRI studies completed in 2015. Electronic health record and radiology report reviews abstracted malignancy presence or absence, prior imaging, and breast subspecialists’ recommendations regarding ILLs for random sets of 30 patients: ILLs with follow-up recommendations, ILLs without recommendations, and without ILLs. Two abdominal radiologists evaluated MRI liver findings and offered follow-up recommendations in consensus. The primary outcome was agreement between breast and abdominal subspecialists in patients with ILL follow-up recommendations compared with those without (χ² analysis). Secondary outcomes were agreement between subspecialists when ILLs were reported and referring clinicians’ adherence to follow-up recommendations.ResultsILLs were identified in 11.3% of breast MRI reports (247 of 2,181); breast subspecialists made follow-up recommendations in 12% of them (30 of 247). Abdominal subspecialists agreed with breast subspecialists when ILLs required no follow-up (29 of 30 cases) but disagreed with 28 of 30 breast subspecialists’ follow-up recommendations (agreement proportion 29 of 30 versus 2 of 30, P < .0001). Subspecialists agreed in 93% of cases (28 of 30) when breast imagers reported no ILLs. Overall, 16 of 30 breast subspecialists’ follow-up recommendations were performed; ILLs were benign in 15.ConclusionsAbdominal subspecialists disagreed frequently with breast subspecialists regarding follow-up recommendations for ILLs on breast MRI. Abdominal subspecialty consultation or embedding liver imaging decision support in breast imaging reporting workflow may reduce unnecessary imaging and improve care. Improvement opportunities may exist in other cross-subspecialty interpretation workflows.     

Assessing the use of digital radiography and a real-time interactive pulmonary nodule analysis system for large population lung cancer screening

Rationale and objectives

To assess the use of chest digital radiograph (DR) assisted with a real-time interactive pulmonary nodule analysis system in large population lung cancer screening.

Materials and methods

346 DR/CR patient studies with corresponding CT images were selected from 12,500 patients screened for lung cancer from year 2007 to 2009. Two expert chest radiologists established CT-confirmed Gold Standard of nodules on DR/CR images with consensus. These cases were read by eight other chest radiologists (participating radiologists) first without using a real-time interactive pulmonary nodule analysis system and then re-read using the system. Performances of participating radiologists and the computer system were analyzed.

Results

The computer system achieved similar performance on DR and CR images, with a detection rate of 76% and an average FPs of 2.0 per image. Before and after using the computer-aided detection system, the nodule detection sensitivities of the participating radiologists were 62.3% and 77.3% respectively, and the A_z values increased from 0.794 to 0.831. Statistical analysis demonstrated statically significant improvement for the participating radiologists after using the computer analysis system with a P-value 0.05.

Conclusion

The computer system could help radiologists identify more lesions, especially small ones that are more likely to be overlooked on chest DR/CR images, and could help reduce inter-observer diagnostic variations, while its FPs were easy to recognize and dismiss. It is suggested that DR/CR assisted by the real-time interactive pulmonary nodule analysis system may be an effective means to screen large populations for lung cancer.     

Guidelines for the Evaluation of Pulmonary Nodules Detected Incidentally or by Screening: A Survey of Radiologist Awareness,Agreement, and Adherence From the Watch the Spot Trial

PurposeThe aim of this study was to examine radiologists’ beliefs about existing guidelines for pulmonary nodule evaluation.MethodsA self-administered survey was developed to ascertain awareness of, agreement with, and adherence to published guidelines, including those from the Fleischner Society and the Lung CT Screening Reporting and Data System (Lung-RADS™). Surveys were distributed to 514 radiologists at 13 health care systems that are participating in a large, pragmatic trial of pulmonary nodule evaluation. Prespecified comparisons were made among groups defined by type of health system, years of experience, reader volume, and study arm.ResultsThe response rate was 26.3%. Respondents were most familiar with guidelines from Fleischner (94%) and Lung-RADS (71%). For both incidental and screening-detected nodules, self-reported adherence to preferred guidelines was very high (97% and 94%, respectively), and most respondents believed that the benefits of adherence outweigh the harms (81% and 74%, respectively). Underlying evidence was thought to be high in quality by 68% of respondents for screening-detected nodules and 41% for incidental nodules. Approximately 70% of respondents believed that the frequency of recommended follow-up was “just right” for both guidelines. Radiologists who practice in nonintegrated health care systems were more likely to believe that the evidence was high in quality (79.5% versus 57.1%) and that the benefits of adherence outweigh the harms (85.1% versus 67.5%). Low-volume readers had lower awareness and self-reported adherence than higher volume readers.ConclusionsRadiologists reported high levels of familiarity and agreement with and adherence to guidelines for pulmonary nodule evaluation, but many overestimated the quality of evidence in support of the recommendations.     

Digital tomosynthesis and ground glass nodules: Optimization of acquisition protocol. A phantom study

IntroductionGround-glass nodules may be the expression of benign conditions, pre-invasive lesions or malignancies. The aim of our study was to evaluate the capability of chest digital tomosynthesis (DTS) in detecting pulmonary ground-glass opacities (GGOs).MethodsAn anthropomorphic chest phantom and synthetic nodules were used to simulate pulmonary ground-glass nodules. The nodules were positioned in 3 different regions (apex, hilum and basal); then the phantom was scanned by multi-detector CT (MDCT) and DTS. For each set (nodule-free phantom, nodule in apical zone, nodule in hilar zone, nodule in basal zone) seven different scans (n = 28) were performed varying the following technical parameters: Cu-filter (0.1–0.3 mm), dose rateo (10–25) and X-ray tube voltage (105–125 kVp). Two radiologists in consensus evaluated the DTS images and provided in agreement a visual score: 1 for unidentifiable nodules, 2 for poorly identifiable nodules, 3 for nodules identifiable with fair certainty, 4 for nodules identifiable with absolute certainty.ResultsIncreasing the dose rateo from 10 to 15, GGOs located in the apex and in the basal zone were better identified (from a score = 2 to a score = 3). GGOs located in the hilar zone were not visible even with a higher dose rate. Intermediate density GGOs had a good visibility score (score = 3) and it did not improve by varying technical parameters. A progressive increase of voltage (from 105 kVp to 125 kVp) did not provide a better nodule visibility.ConclusionDTS with optimized technical parameters can identify GGOs, in particular those with a diameter greater than 10 mm.Implications for practiceDTS could have a role in the follow-up of patients with known GGOs identified in lung apex or base region.