Implementation of an Institution-Wide Rules-Based Automated CT Protocoling System.

BACKGROUND. Examination protocoling is a noninterpretive task that increases radiologists' workload and can cause workflow inefficiencies. OBJECTIVE. The purpose of this study was to evaluate effects of an automated CT protocoling system on examination process times and protocol error rates. METHODS. This retrospective study included 317,597 CT examinations (mean age, 61.8 ± 18.1 [SD] years; male, 161,125; female, 156,447; unspecified sex, 25) from July 2020 to June 2022. A rules-based automated protocoling system was implemented institution-wide; the system evaluated all CT orders in the EHR and assigned a protocol or directed the order for manual radiologist protocoling. The study period comprised pilot (July 2020 to December 2020), implementation (January 2021 to December 2021), and postimplementation (January 2022 to June 2022) phases. Proportions of automatically protocoled examinations were summarized. Process times were recorded. Protocol error rates were assessed by counts of quality improvement (QI) reports and examination recalls and comparison with retrospectively assigned protocols in 450 randomly selected examinations. RESULTS. Frequency of automatic protocoling was 19,366/70,780 (27.4%), 68,875/163,068 (42.2%), and 54,045/83,749 (64.5%) in pilot, implementation, and postimplementation phases, respectively (p < .001). Mean (± SD) times from order entry to protocol assignment for automatically and manually protocoled examinations for emergency department examinations were 0.2 ± 18.2 and 2.1 ± 69.7 hours, respectively; mean inpatient examination times were 0.5 ± 50.0 and 3.5 ± 105.5 hours; and mean outpatient examination times were 361.7 ± 1165.5 and 1289.9 ± 2050.9 hours (all p < .001). Mean (± SD) times from order entry to examination completion for automatically and manually protocoled examinations for emergency department examinations were 2.6 ± 38.6 and 4.2 ± 73.0 hours, respectively (p < .001); for inpatient examinations were 6.3 ± 74.6 and 8.7 ± 109.3 hours (p = .001); and for outpatient examinations were 1367.2 ± 1795.8 and 1471.8 ± 2118.3 hours (p < .001). In the three phases, there were three, 19, and 25 QI reports and zero, one, and three recalls, respectively, for automatically protocoled examinations, versus nine, 19, and five QI reports and one, seven, and zero recalls for manually protocoled examinations. Retrospectively assigned protocols were concordant with 212/214 (99.1%) of automatically protocoled versus 233/236 (98.7%) of manually protocoled examinations. CONCLUSION. The automated protocoling system substantially reduced radiologists' protocoling workload and decreased times from order entry to protocol assignment and examination completion; protocol errors and recalls were infrequent. CLINICAL IMPACT. The system represents a solution for reducing radiologists' time spent performing noninterpretive tasks and improving care efficiency.

Evaluation of an Artificial Intelligence Model for Detection of Pneumothorax and Tension Pneumothorax in Chest Radiographs.

Importance: Early detection of pneumothorax, most often via chest radiography, can help determine need for emergent clinical intervention. The ability to accurately detect and rapidly triage pneumothorax with an artificial intelligence (AI) model could assist with earlier identification and improve care. Objective: To compare the accuracy of an AI model vs consensus thoracic radiologist interpretations in detecting any pneumothorax (incorporating both nontension and tension pneumothorax) and tension pneumothorax. Design, Setting, and Participants: This diagnostic study was a retrospective standalone performance assessment using a data set of 1000 chest radiographs captured between June 1, 2015, and May 31, 2021. The radiographs were obtained from patients aged at least 18 years at 4 hospitals in the Mass General Brigham hospital network in the United States. Included radiographs were selected using 2 strategies from all chest radiography performed at the hospitals, including inpatient and outpatient. The first strategy identified consecutive radiographs with pneumothorax through a manual review of radiology reports, and the second strategy identified consecutive radiographs with tension pneumothorax using natural language processing. For both strategies, negative radiographs were selected by taking the next negative radiograph acquired from the same radiography machine as each positive radiograph. The final data set was an amalgamation of these processes. Each radiograph was interpreted independently by up to 3 radiologists to establish consensus ground-truth interpretations. Each radiograph was then interpreted by the AI model for the presence of pneumothorax and tension pneumothorax. This study was conducted between July and October 2021, with the primary analysis performed between October and November 2021. Main Outcomes and Measures: The primary end points were the areas under the receiver operating characteristic curves (AUCs) for the detection of pneumothorax and tension pneumothorax. The secondary end points were the sensitivities and specificities for the detection of pneumothorax and tension pneumothorax. Results: The final analysis included radiographs from 985 patients (mean [SD] age, 60.8 [19.0] years; 436 [44.3%] female patients), including 307 patients with nontension pneumothorax, 128 patients with tension pneumothorax, and 550 patients without pneumothorax. The AI model detected any pneumothorax with an AUC of 0.979 (95% CI, 0.970-0.987), sensitivity of 94.3% (95% CI, 92.0%-96.3%), and specificity of 92.0% (95% CI, 89.6%-94.2%) and tension pneumothorax with an AUC of 0.987 (95% CI, 0.980-0.992), sensitivity of 94.5% (95% CI, 90.6%-97.7%), and specificity of 95.3% (95% CI, 93.9%-96.6%). Conclusions and Relevance: These findings suggest that the assessed AI model accurately detected pneumothorax and tension pneumothorax in this chest radiograph data set. The model's use in the clinical workflow could lead to earlier identification and improved care for patients with pneumothorax.

Management and Outcomes of Suspected Infectious and Inflammatory Lung Abnormalities Identified on Lung Cancer Screening CT.

BACKGROUND. Incidental findings are frequently encountered during lung cancer screening (LCS). Limited data describe the prevalence of suspected acute infectious and inflammatory lung processes on LCS and how they should be managed. OBJECTIVE. The purpose of this study was to determine the prevalence, radiologic reporting and management, and outcome of suspected infectious and inflammatory lung processes identified incidentally during LCS and to propose a management algorithm. METHODS. This retrospective study included 6314 low-dose CT (LDCT) examinations performed between June 2014 and April 2019 in 3800 patients as part of an established LCS program. Radiology reports were reviewed, and patients with potentially infectious or inflammatory lung abnormalities were identified and analyzed for descriptors of imaging findings, Lung-RADS designation, recommendations, and clinical outcomes. Using the descriptors, outcomes, and a greater than 2% threshold risk of malignancy, a follow-up algorithm was developed to decrease additional imaging without affecting cancer detection. RESULTS. A total of 331/3800 (8.7%) patients (178 men, 153 women; mean age [range], 66 [53-87] years) undergoing LCS had lung findings that were attributed to infection or inflammation. These abnormalities were reported as potentially significant findings using the S modifier in 149/331 (45.0%) and as the dominant nodule used to determine the Lung-RADS category in 96/331 (29.0%). Abnormalities were multiple or multifocal in 260/331 (78.5%). Common descriptors were ground-glass (155/331; 46.8%), tree-in-bud (56/331; 16.9%), consolidation (41/331; 12.4%), and clustered (67/331; 20.2%) opacities. A follow-up chest CT outside of screening was performed within 12 months or less in 264/331 (79.8%) and within 6 months or less in 186/331 (56.2%). A total of 260/331 (78.5%) opacities resolved on follow-up imaging. Two malignancies (2/331; 0.6%) were associated with these abnormalities and both had consolidations. Theoretic adoption of a proposed management algorithm for suspected infectious and inflammatory findings reduced unnecessary follow-up imaging by 82.6% without missing a single malignancy. CONCLUSION. Presumed acute infectious or inflammatory lung abnormalities are frequently encountered in the setting of LCS. These opacities are commonly multifocal and resolve on follow-up. Less than 1% are associated with malignancy. CLINICAL IMPACT. Adoption of a conservative management algorithm can standardize recommendations and reduce unnecessary imaging without increasing the risk of missing a malignancy.

Accessory and Incomplete Lung Fissures: Clinical and Histopathologic Implications.

OBJECTIVE: This article reviews the anatomy, histology, and disease processes of pulmonary fissures, with emphasis on clinical implications of accessory and incomplete fissures. CONCLUSION: Accessory and incomplete pulmonary fissures are often overlooked during routine imaging but can have profound clinical importance. Knowledge of fissure anatomy could improve diagnostic accuracy and inform prognosis for oncologists, interventional pulmonologists, and thoracic surgeons.

Detection of Extrapulmonary Malignancy During Lung Cancer Screening: 5-Year Analysis at a Tertiary Hospital.

PURPOSE: The aims of this study were to determine the prevalence and outcomes of extrapulmonary malignancies identified on lung cancer screening (LCS) and to determine the cost associated with the investigation of these lesions. METHODS: This retrospective study included 7,414 low-dose CT studies performed between June 2014 and December 2019 on 4,160 patients as part of an established LCS program. Patients with indeterminate extrapulmonary lesions were identified, and the diagnostic workup, management, and outcomes of the lesions were determined. Costs related to diagnostic evaluation were estimated using 2020 total facility relative value units and the 2020 Medicare conversion factor. Out-of-pocket costs were extracted from billing records. RESULTS: There were 20 extrapulmonary malignancies among 241 reported lesions in 225 patients (mean age, 66.1 ± 6.4 years; 109 men, 116 women). The prevalence of extrapulmonary malignancy was 20 of 4,160 (0.48%). Early-stage cancers were detected in 13 of 20 (65%). No cancer-specific mortality was observed. The predictive value for malignancy varied by organ (P = .03) and was highest in the chest wall and axilla (36.4%), followed by bone (25%). The average cost on the basis of Medicare reimbursement for diagnosis of an extrapulmonary malignancy on LCS was $1,316.03 ($6.33 per participant and $109.21 per indeterminate incidental lesion). Most patients (203 of 225 [90.2%]) did not have out-of-pocket costs related to diagnostic workup. In those who did, the median cost was $160.60 (range, $75-$606.76). CONCLUSIONS: Low-dose CT for LCS detects extrapulmonary malignancy with high predictive value for certain locations. There is cost associated in the workup related to these incidental lesions, but most malignancies are detected at early stages and have good outcomes.

Comparison of image quality and radiation doses between rapid kV-switching and dual-source DECT techniques in the chest.

PURPOSE: To compare image quality and radiation doses for chest DECT acquired with dual-source and rapid-kV switching techniques. MATERIALS AND METHODS: Our institutional Review Board approved retrospective study included 97 patients (54 men, 43 women; 63 ±â€¯14 years) who underwent contrast-enhanced chest DECT with both single source, rapid kV-switching (SS-DECT) and dual source (DS-DECT) techniques per standard of care departmental protocols. Reconstructed images from both scanners had identical section thickness and section interval for virtual monoenergetic and material decomposition iodine (MDI) images. Two thoracic radiologists independently evaluated all DECT for findings, quality of images, perfusion defects (MDI), and presence of artifacts. Radiation dose descriptor, size-specific dose estimates (SSDE), was recorded. Data were analyzed with Wilcoxon Signed Rank and Cohen's Kappa tests. RESULTS: There were no significant differences in patient weight or SSDE for the two DECT techniques (p > 0.06). Both radiologists reported no difference in lesion and artifact evaluation on the virtual monoenergetic images from either technique (p > 0.05). However, SS-DECT (in 63-71/97 patients) had substantial artifactual heterogeneity in pulmonary perfusion on MDI images compared to none on DS-DECT (p < 0.001). CONCLUSION: Despite identical patients and associated radiation doses, there were substantial differences in material decomposition iodine images generated from SS-DECT and DS-DECT techniques. Pulmonary heterogeneity on MDI images from SS-DECT leads to artifactual areas of low perfusion and can confound interpretation of true pulmonary perfusion.

Safety and Success of Repeat Lung Needle Biopsies in Patients with Epidermal Growth Factor Receptor-Mutant Lung Cancer.

BACKGROUND: Postprogression repeat biopsies are critical in caring for patients with lung cancer with epidermal growth factor receptor (EGFR) mutations. However, hesitation about invasive procedures persists. We assessed safety and tissue adequacy for molecular profiling among repeat postprogression percutaneous transthoracic needle aspirations and biopsies (rebiopsies). MATERIALS AND METHODS: All lung biopsies performed at our hospital from 2009 to 2017 were reviewed. Complications were classified by Society of Interventional Radiology criteria. Complication rates between rebiopsies in EGFR-mutants and all other lung biopsies (controls) were compared using Fisher's exact test. Success of molecular profiling was recorded. RESULTS: During the study period, nine thoracic radiologists performed 107 rebiopsies in 75 EGFR-mutant patients and 2,635 lung biopsies in 2,347 patients for other indications. All biopsies were performed with computed tomography guidance, coaxial technique, and rapid on-site pathologic evaluation (ROSE). The default procedure was to take 22-gauge fine-needle aspirates (FNA) followed by 20-gauge tissue cores. Minor complications occurred in 9 (8.4%) rebiopsies and 503 (19.1%; p = .004) controls, including pneumothoraces not requiring chest tube placement (4 [3.7%] vs. 426 [16.2%] in rebiopsies and controls, respectively; p < .001). The only major complication was pneumothorax requiring chest tube placement, occurring in zero rebiopsies and 38 (1.4%; p = .4) controls. Molecular profiling was requested in 96 (90%) rebiopsies and successful in 92/96 (96%). CONCLUSION: At our center, repeat lung biopsies for postprogression molecular profiling of EGFR-mutant lung cancers result in fewer complications than typical lung biopsies. Coaxial technique, FNA, ROSE, and multiple 20-gauge tissue cores result in excellent specimen adequacy. IMPLICATIONS FOR PRACTICE: Repeat percutaneous transthoracic needle aspirations and biopsies for postprogression molecular profiling of epidermal growth factor receptor (EGFR)-mutant lung cancer are safe in everday clinical practice. Coaxial technique, fine-needle aspirates, rapid on-site pathologic evaluation, and multiple 20-gauge tissue cores result in excellent specimen adequacy. Although liquid biopsies are increasingly used, their sensitivity for analysis of resistant EGFR-mutant lung cancers remains limited. Tissue biopsies remain important in this context, especially because osimertinib is now in the frontline setting and T790M is no longer the major finding of interest on molecular profiling.

Complications and Accuracy of Computed Tomography-guided Transthoracic Needle Biopsy in Patients Over 80 Years of Age.

OBJECTIVES: The purpose of this study was to evaluate the complications and diagnostic accuracy of computed tomography-guided percutaneous transthoracic needle biopsy (PTNB) in patients aged 80 years and older. MATERIALS AND METHODS: Consecutive PTNB procedures performed in an academic institution between July 2009 and June 2013 were reviewed. Procedures were performed according to a standard protocol using conscious sedation and rapid on-site pathology evaluation. Patient demographics, lesion characteristics, complications, and final tissue diagnosis were reviewed. Patients below 80 years of age and over 80 years were compared using binary logistic regression. RESULTS: Of 894 biopsies, 141 (16%) were performed on patients over 80 years of age. Comparison of patients over and below 80 years of age did not differ significantly with regard to lesion size and morphology (P=0.663 and 0.453, respectively), and diagnostic accuracy (P=0.268). Pneumothorax rates were 23% versus 24% (P=0.682), and chest tube insertion was required in 2% of both groups (P=0.924). Hemoptysis rates were 3% versus 2% (P=0.376). CONCLUSIONS: PTNB is a safe and accurate procedure in patients aged 80 years and older. Complications and diagnostic accuracy are similar to those observed in younger patients.

Missed Lung Cancer.

The chest radiograph is one of the most commonly used imaging studies and is the modality of choice for initial evaluation of many common clinical scenarios. Over the last two decades, chest computed tomography has been increasingly used for a wide variety of indications, including respiratory illnesses, trauma, oncologic staging, and more recently lung cancer screening. Diagnostic radiologists should be familiar with the common causes of missed lung cancers on imaging studies in order to avoid detection and interpretation errors. Failure to detect these lesions can potentially have serious implications for both patients as well as the interpreting radiologist.

Bedside Chest Radiographs in the Intensive care Setting: Wireless Direct Radiography Compared to Computed Radiography.

OBJECTIVES: To compare image quality, visibility of anatomic landmarks, tubes and lines, and other clinically significant findings on portable (bedside) chest radiographs acquired with wireless direct radiography (DRw) and computed radiography (CR). METHODS: In a prospective IRB-approved and HIPAA-compliant study, portable DRw (DRX-1C mobile retrofit portable wireless direct radiography, CareStream Inc., Rochester, NY) and portable CR (AGFA CR (DXG) version; NIM2103, AGFA Healthcare, Ridgefield Park, NJ) images of the chest were acquired within 24-hours in 80 patients in the intensive care unit (ICU). Image pairs of 75 patients (37% female) with a mean age of 60.7±16 years were independently compared side-by-side by 7 experienced thoracic radiologists using a five-point scale. When tubes and lines were present, the radiologist also compared an edge-enhanced copy of the DRw image to the CR image. RESULTS: Most radiologists found significantly fewer artifacts on DRw images compared to CR images and all readers agreed that when present, these artifacts did not significantly preclude the ability to evaluate anatomic landmarks, tubes and lines, or clinically significant findings. None of the radiologists (0/7) reported superior visibility of anatomic structures on CR images compared to DRw images and some radiologists (3/7) found DRw images significantly better for visibility of anatomic landmarks such as the carina (p=0.01-0.001). Most radiologists (6/7) found DRw images to be better or clearly better than CR images for position of tubes and lines, and edge-enhanced DRw images to be especially helpful for evaluation of central venous catheters and esophageal tubes (p=0.027-0.001). None of the radiologists deemed CR images superior for visibility of clinically significant findings. CONCLUSIONS: Critical care chest radiography with a portable DRw system can provide similar or superior information compared to a CR system regarding clinically significant findings and position of tubes and lines.

Lung Cancer Screening: Why, When, and How?

This article explains the rationale of lung cancer screening with low-dose computed tomography and provides a practical approach to all relevant aspects of a lung cancer screening program. Imaging protocols, patient eligibility criteria, facility readiness, and reimbursement criteria are addressed step by step. Diagnostic criteria and Lung-RADS (Lung Computed Tomography Screening Reporting and Data System) nodule management pathways are illustrated with examples. Pearls and pitfalls for interpretation of lung cancer screening low-dose chest computed tomography are discussed.

Pulmonary Artery Pseudoaneurysms: Clinical Features and CT Findings.

OBJECTIVE: The purpose of this study was to analyze the clinical and CT features of pulmonary artery pseudoaneurysms (PAPs). MATERIALS AND METHODS: A database search of chest CT examinations performed from January 1, 2000 to December 31, 2014 identified 24 patients with findings consistent with PAPs. A CT finding consistent with a PAP was defined as a focal saccular outpouching of a pulmonary artery. Medical records were reviewed to determine clinical presentations, treatments, and outcomes. CT scans were reviewed by two board-certified fellowship-trained chest radiologists. RESULTS: A total of 35 PAPs were identified in 24 patients. Hemoptysis and shortness of breath were the most common presenting symptoms. The most commonly identified causes of PAPs were infection (33%), neoplasms (13%), and trauma (17%). Of the 35 PAPs, 29 (83%) were located in segmental or subsegmental pulmonary arteries. A solitary PAP was identified in 20 (83%) patients, and multiple PAPs were identified in three patients with endocarditis and one patient with pulmonary metastases. Only three of 35 (9%) PAPs were associated with a ground-glass halo. Endovascular treatment was successfully performed in 12 patients, and only one patient had immediate recurrent hemoptysis after treatment. PAP was clinically suspected by the referring clinicians in only three patients. Sixteen of the 35 (46%) PAPs were not reported on the initial CT studies. CONCLUSION: PAPs showed a strong predilection for the peripheral pulmonary arteries. Multiplicity of PAPs can be seen in the settings of endocarditis and pulmonary metastatic disease. Most PAPs were not associated with a ground-glass halo. PAPs can be lethal but were often not suspected clinically and were underreported by radiologists.

Imaging of Eosinophilic Lung Diseases.

Eosinophilic lung diseases encompass a broad range of conditions wherein patients present with pulmonary opacities and eosinophilia of the serum, pulmonary tissue, or bronchoalveolar lavage fluid. Many of these entities can be idiopathic or are secondary to parasitic infection, exposure to drugs, toxins, or radiation. These diseases exhibit a wide range of imaging findings, including consolidation, ground-glass opacities, nodules, and masses. Diagnoses often require bronchoalveolar lavage and/or biopsy to confirm respiratory eosinophilia and to exclude other entities, such as infection or malignancy. Treatment entails administration of corticosteroids, removal of inciting agents, and treatment of underlying infection.

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

PURPOSE: To 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. METHODS: The 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. RESULTS: A 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). CONCLUSIONS: A point-of-care CDS tool was associated with improved adherence to guidelines for follow-up of incidental pulmonary nodules.

The 10 Pillars of Lung Cancer Screening: Rationale and Logistics of a Lung Cancer Screening Program.

On the basis of the National Lung Screening Trial data released in 2011, the U.S. Preventive Services Task Force made lung cancer screening (LCS) with low-dose computed tomography (CT) a public health recommendation in 2013. The Centers for Medicare and Medicaid Services (CMS) currently reimburse LCS for asymptomatic individuals aged 55-77 years who have a tobacco smoking history of at least 30 pack-years and who are either currently smoking or had quit less than 15 years earlier. Commercial insurers reimburse the cost of LCS for individuals aged 55-80 years with the same smoking history. Effective care for the millions of Americans who qualify for LCS requires an organized step-wise approach. The 10-pillar model reflects the elements required to support a successful LCS program: eligibility, education, examination ordering, image acquisition, image review, communication, referral network, quality improvement, reimbursement, and research frontiers. Examination ordering can be coupled with decision support to ensure that only eligible individuals undergo LCS. Communication of results revolves around the Lung Imaging Reporting and Data System (Lung-RADS) from the American College of Radiology. Lung-RADS is a structured decision-oriented reporting system designed to minimize the rate of false-positive screening examination results. With nodule size and morphology as discriminators, Lung-RADS links nodule management pathways to the variety of nodules present on LCS CT studies. Tracking of patient outcomes is facilitated by a CMS-approved national registry maintained by the American College of Radiology. Online supplemental material is available for this article.

Diagnostic Yield of CT-Guided Percutaneous Transthoracic Needle Biopsy for Diagnosis of Anterior Mediastinal Masses.

OBJECTIVE: The purpose of this study was to evaluate the diagnostic yield and accuracy of CT-guided percutaneous biopsy of anterior mediastinal masses and assess prebiopsy characteristics that may help to select patients with the highest diagnostic yield. MATERIALS AND METHODS: Retrospective review of all CT-guided percutaneous biopsies of the anterior mediastinum conducted at our institution from January 2003 through December 2012 was performed to collect data regarding patient demographics, imaging characteristics of biopsied masses, presence of complications, and subsequent surgical intervention or medical treatment (or both). Cytology, core biopsy pathology, and surgical pathology results were recorded. A per-patient analysis was performed using two-tailed t test, Fisher's exact test, and Pearson chi-square test. RESULTS: The study cohort included 52 patients (32 men, 20 women; mean age, 49 years) with mean diameter of mediastinal mass of 6.9 cm. Diagnostic yield of CT-guided percutaneous biopsy was 77% (40/52), highest for thymic neoplasms (100% [11/11]). Non-diagnostic results were seen in 12 of 52 patients (23%), primarily in patients with lymphoma (75% [9/12]). Fine-needle aspiration yielded the correct diagnosis in 31 of 52 patients (60%), and core biopsy had a diagnostic rate of 77% (36/47). None of the core biopsies were discordant with surgical pathology. There was no statistically significant difference between the diagnostic and the nondiagnostic groups in patient age, lesion size, and presence of necrosis. The complication rate was 3.8% (2/52), all small self-resolving pneumothoraces. CONCLUSION: CT-guided percutaneous biopsy is a safe diagnostic procedure with high diagnostic yield (77%) for anterior mediastinal lesions, highest for thymic neoplasms (100%), and can potentially obviate more invasive procedures.

Correlation of the Strength of Recommendations for Additional Imaging to Adherence Rate and Diagnostic Yield.

PURPOSE: The aim of this study was to evaluate the association between the wording of radiologist recommendations for chest CT with the likelihood of recommendation adherence and the diagnostic yield of the recommended follow-up CT imaging. METHODS: This HIPAA-compliant retrospective study had institutional review board approval, including waiver of the requirement for patient consent. All outpatient chest radiographic (CXR) studies performed at a tertiary care academic medical center in 2008 (n = 29,138) were searched to identify examinations with recommendations for chest CT. The wording of chest CT recommendations was classified as conditional or absolute, on the basis of whether the recommendation stood independent of the clinical judgment of the ordering clinician. Using the radiology information system, patients who underwent chest CT within 90 days of the index CXR study containing the recommendation were determined, and the CT studies were evaluated to determine if there were abnormalities corresponding to the CXR abnormalities that prompted the recommendations. Corresponding abnormalities were categorized as clinically relevant or not, on the basis of whether further workup or treatment was warranted. Groups were compared using t tests and Fisher exact tests. RESULTS: Recommendations for chest CT appeared in 4.5% of outpatient CXR studies (1,316 of 29,138; 95% confidence interval [CI], 4.3%-4.8%); 39.4% (519 of 1,316; 95% CI, 36.8%-42.0%) were conditional and 60.6% (797 of 1,316; 95% CI, 58.0%-63.2%) were absolute. Patients with absolute recommendations were significantly more likely to undergo follow-up chest CT within 90 days than patients with conditional recommendations (67.8% vs 45.8%, respectively, P < .001). Despite this difference in provider adherence, there was no significant difference between the conditional and absolute recommendation groups with regard to the incidence of clinically relevant corresponding findings (P = .16) or malignancy (P = .08) on follow-up CT. CONCLUSIONS: Conditional radiologist recommendations are associated with decreased provider adherence, though the likelihood of a clinically relevant finding on follow-up CT is no different than with absolute recommendations.

Diagnostic yield of recommendations for chest CT examination prompted by outpatient chest radiographic findings.

PURPOSE: To evaluate the diagnostic yield of recommended chest computed tomography (CT) prompted by abnormalities detected on outpatient chest radiographic images. MATERIALS AND METHODS: This HIPAA-compliant study had institutional review board approval; informed consent was waived. Reports of all outpatient chest radiographic examinations performed at a large academic center during 2008 (n = 29 138) were queried to identify studies that included a recommendation for a chest CT imaging. The radiology information system was queried for these patients to determine if a chest CT examination was obtained within 1 year of the index radiographic examination that contained the recommendation. For chest CT examinations obtained within 1 year of the index chest radiographic examination and that met inclusion criteria, chest CT images were reviewed to determine if there was an abnormality that corresponded to the chest radiographic finding that prompted the recommendation. All corresponding abnormalities were categorized as clinically relevant or not clinically relevant, based on whether further work-up or treatment was warranted. Groups were compared by using t test and Fisher exact test with a Bonferroni correction applied for multiple comparisons. RESULTS: There were 4.5% (1316 of 29138 [95% confidence interval {CI}: 4.3%, 4.8%]) of outpatient chest radiographic examinations that contained a recommendation for chest CT examination, and increasing patient age (P < .001) and positive smoking history (P = .001) were associated with increased likelihood of a recommendation for chest CT examination. Of patients within this subset who met inclusion criteria, 65.4% (691 of 1057 [95% CI: 62.4%, 68.2%) underwent a chest CT examination within the year after the index chest radiographic examination. Clinically relevant corresponding abnormalities were present on chest CT images in 41.4% (286 of 691 [95% CI: 37.7%, 45.2%]) of cases, nonclinically relevant corresponding abnormalities in 20.6% (142 of 691 [95% CI: 17.6%, 23.8%]) of cases, and no corresponding abnormalities in 38.1% (263 of 691 [95% CI: 34.4%, 41.8%]) of cases. Newly diagnosed, biopsy-proven malignancies were detected in 8.1% (56 of 691 [95% CI: 6.2%, 10.4%]) of cases. CONCLUSION: A radiologist recommendation for chest CT to evaluate an abnormal finding on an outpatient chest radiographic examination has a high yield of clinically relevant findings.

The imaging spectrum of bronchopulmonary sequestration.

Bronchopulmonary sequestration is a rare lesion characterized by abnormal lung tissue that lacks a normal bronchial communication and is supplied by an anomalous systemic artery. It has a variety of imaging appearances, including that of consolidation, a mass, or an air or fluid-filled cystic or multicystic lesion. This article reviews the imaging spectrum of bronchopulmonary sequestration, its important parenchymal mimics, and conditions that share the feature of anomalous systemic arterial supply to the lung.