Recent Trends in the Identification of Incidental Pulmonary Nodules.

RATIONALE: Pulmonary nodules are common incidental findings, but information about their incidence in the era of computed tomography (CT) is lacking. OBJECTIVES: To examine recent trends in pulmonary nodule identification. METHODS: We used electronic health records and natural language processing to identify members of an integrated health system who had nodules measuring 4 to 30 mm. We calculated rates of chest CT imaging, nodule identification, and receipt of a new lung cancer diagnosis within 2 years of nodule identification, and standardized rates by age and sex to estimate the frequency of nodule identification in the U.S. population in 2010. MEASUREMENTS AND MAIN RESULTS: Between 2006 and 2012, more than 200,000 adult members underwent 415,581 chest CT examinations. The annual frequency of chest CT imaging increased from 1.3 to 1.9% for all adult members, whereas the frequency of nodule identification increased from 24 to 31% for all scans performed. The annual rate of chest CT increased from 15.4 to 20.7 per 1,000 person-years, and the rate of nodule identification increased from 3.9 to 6.6 per 1,000 person-years, whereas the rate of a new lung cancer diagnosis remained stable. By extrapolation, more than 4.8 million Americans underwent at least one chest CT scan and 1.57 million had a nodule identified, including 63,000 who received a new lung cancer diagnosis within 2 years. CONCLUSIONS: Incidental pulmonary nodules are an increasingly common consequence of routine medical care, with an incidence that is much greater than recognized previously. More frequent nodule identification has not been accompanied by increases in the diagnosis of cancerous nodules.

Prediction of malignancy in cystic neoplasms of the pancreas: a population-based cohort study.

OBJECTIVES: Pancreatic cystic neoplasms (PCNs) are being detected with increased frequency. The aims of this study were to determine the incidence of malignancy and develop an imaging-based system for prediction of malignancy in PCN. METHODS: We conducted a retrospective cohort study of patients ≥18 years of age with confirmed PCN from January 2005 to December 2010 in a community-based integrated care setting in Southern California. Patients with history of acute or chronic pancreatitis were excluded. Malignancy diagnosed within 3 months of cyst diagnosis was considered as pre-existing. Subsequent incidence of malignancy during surveillance was calculated based on person-time at risk. Age- and gender-adjusted standardized incidence ratio (SIR) was calculated with the non-cyst reference population. Recursive partitioning was used to develop a risk prediction model based on cyst imaging features. RESULTS: We identified 1,815 patients with confirmed PCN. A total of 53 (2.9%) of patients were diagnosed with cyst-related malignancy during the study period. The surveillance cohort consisted of 1,735 patients with median follow-up of 23.4 months. Incidence of malignancy was 0.4% per year during surveillance. The overall age- and gender-adjusted SIR for pancreatic malignancy was 35.0 (95% confidence level 26.6, 46.0). Using recursive partitioning, we stratified patients into low (<1%), intermediate (1-5%), and high (9-14%) risk of harboring malignant PCN based on four cross-sectional imaging features: size, pancreatic duct dilatation, septations with calcification as well as growth. Area under the receiver operator characteristic curve for the prediction model was 0.822 (training) and 0.808 (testing). CONCLUSIONS: Risk of pancreatic malignancy was lower than previous reports from surgical series but was still significantly higher than the reference population. A risk stratification system based on established imaging criteria may help guide future management decisions for patients with PCN.

Imaging appearance in acute liver failure: correlation with clinical and pathology findings.

BACKGROUND AND AIM: Acute liver failure (ALF) is characterized by sudden liver injury without underlying chronic liver disease. Excluding underlying cirrhosis in these patients is often difficult and liver biopsy may be impractical. We review the imaging appearance of acute hepatic failure in patients who underwent transplant and correlate these findings with clinical, laboratory and pathology parameters. METHODS: This is a retrospective review of 47 patients without known chronic liver disease who presented to three institutions between 2002 and 2010 with ALF, 46 of which underwent subsequent orthotopic liver transplantation. Pre-transplant ultrasound, computed tomography and magnetic resonance imaging scans were reviewed for parenchymal homogeneity, surface nodularity and evidence of portal hypertension. Explant histopathology, laboratory values and time intervals between symptom onset to initial imaging and transplant were correlated with imaging findings. RESULTS: The majority of patients with ALF had abnormal radiographic findings. Ascites was seen in 65% of patients. Splenomegaly, collateral vessel formation and hepatofugal flow in the portal vein were present in 28, 15 and 9% of patients, respectively. Nodular liver surface was noted in 23% of patients, more commonly in patients who had been ill for more than 7 days. Liver surface nodularity correlated with massive hepatic necrosis on histology and wrinkled capsule on visual inspection of explanted liver specimen. CONCLUSION: Imaging findings in ALF was variable and can resemble cirrhosis. Assessment for underlying cirrhosis in the setting of liver failure should not be based on imaging findings.

Intravenous urography in evaluation of asymptomatic microscopic hematuria.

BACKGROUND AND PURPOSE: In 2001, the American Urologic Association Best Practice Policy Panel recommended CT or intravenous urography (IVU) over ultrasonography as the initial imaging modality in patients with asymptomatic microhematuria. We here present results of a study initiated many years ago and completed prior to 2001 that provides information pertinent to the use of IVU as the initial imaging modality for such patients. PATIENTS AND METHODS: This study compared the results of IVU and ultrasonography in patients 40+ years of age who were referred to a single urology department for evaluation of microscopic hematuria between 1994 and 2000. There were 290 patients who agreed to participate by undergoing ultrasonography in addition to IVU; 247 completed both tests. There were 81 men and 166 women with a mean age of 56.4 years (range 40-86 years). Thirty patients (12%) were smokers. RESULTS: A renal lesion or mass suggestive of tumor was found in 8 patients (3.2%); 3 patients had this finding on the IVU examination and 5 on ultrasonography. None of the patients had such a lesion/mass on both examinations. Two patients with suspect lesions were ultimately found to have renal-cell carcinoma. Both of the patients with renal cancer had a suspect lesion on the ultrasound examination but not on the contemporaneous IVU. CONCLUSION: Intravenous urography may miss lesions/masses that lead to a diagnosis of upper-tract neoplasia.

Comparison of arthroscopic findings with magnetic resonance imaging and arthrography in children with glenohumeral deformities secondary to brachial plexus birth palsy.

BACKGROUND: Characterization of glenohumeral deformities secondary to brachial plexus birth palsy with plain radiography is difficult because the glenohumeral joint does not completely ossify until puberty. The purpose of this study was to compare the findings on magnetic resonance imaging and arthrography with those on arthroscopy to better understand the roles of these methods in the evaluation of glenohumeral development in this condition. METHODS: Eighty-four children who ranged in age from seven months to thirteen years and six months had glenohumeral arthrography while they were under general anesthesia for operative treatment of an internal rotation contracture. Thirty-six children also received magnetic resonance imaging with use of cartilage-sensitive axial gradient-echo sequences. Thirty-seven children were evaluated arthroscopically. RESULTS: Arthrography showed a concentric glenohumeral joint in thirty-three children, a flat glenoid in eight, a biconcave glenoid in seventeen, and a pseudoglenoid in twenty-six. Thus, 61% (fifty-one) of the eighty-four children with an internal rotation contracture had a substantial deformity. The severity of the contracture was associated with the existence and the type of the deformity (p = 0.001). Magnetic resonance imaging showed greater detail than arthrography did in defining the severity of the deformity in both the glenoid and the humeral head. The thirty-seven children who were examined arthroscopically showed a progression from those who had a concentric, conforming joint to those who had a markedly deformed joint with a bifurcated glenoid and a flattened, oval-shaped humeral head that articulated with the posterior aspect of the glenoid. Irregularities and cavitation of the anterior aspect of the glenoid were common. The subscapularis and rotator interval tissue were the primary sites of contracture. CONCLUSIONS: Profound glenohumeral deformities secondary to brachial plexus birth palsy are commonly seen within the first two years of life. The information provided by imaging studies is helpful in defining the natural history of this condition and in determining the success of surgical intervention.

Automated identification of patients with pulmonary nodules in an integrated health system using administrative health plan data, radiology reports, and natural language processing.

INTRODUCTION: Lung nodules are commonly encountered in clinical practice, yet little is known about their management in community settings. An automated method for identifying patients with lung nodules would greatly facilitate research in this area. METHODS: Using members of a large, community-based health plan from 2006 to 2010, we developed a method to identify patients with lung nodules, by combining five diagnostic codes, four procedural codes, and a natural language processing algorithm that performed free text searches of radiology transcripts. An experienced pulmonologist reviewed a random sample of 116 radiology transcripts, providing a reference standard for the natural language processing algorithm. RESULTS: With the use of an automated method, we identified 7112 unique members as having one or more incident lung nodules. The mean age of the patients was 65 years (standard deviation 14 years). There were slightly more women (54%) than men, and Hispanics and non-whites comprised 45% of the lung nodule cohort. Thirty-six percent were never smokers whereas 11% were current smokers. Fourteen percent of the patients were subsequently diagnosed with lung cancer. The sensitivity and specificity of the natural language processing algorithm for identifying the presence of lung nodules were 96% and 86%, respectively, compared with clinician review. Among the true positive transcripts in the validation sample, only 35% were solitary and unaccompanied by one or more associated findings, and 56% measured 8 to 30 mm in diameter. CONCLUSIONS: A combination of diagnostic codes, procedural codes, and a natural language processing algorithm for free text searching of radiology reports can accurately and efficiently identify patients with incident lung nodules, many of whom are subsequently diagnosed with lung cancer.

Glenohumeral deformity in children with internal rotation contractures secondary to brachial plexus birth palsy: intraoperative arthrographic classification.

PURPOSE: To evaluate, with intraoperative arthrography, joint morphology in children undergoing surgical treatment of residual paralysis of the shoulder resulting in brachial plexus birth palsy and to correlate the morphology with the degree of passive external rotation. MATERIALS AND METHODS: In 64 children (age range, 7 months to 13 years 6 months), an orthopedic surgeon performed intraoperative arthrography and measured passive external rotation while the patient received a general anesthetic. The orthopedic surgeon and three radiologists reviewed arthrograms and in consensus classified glenohumeral joints in one of four categories: concentric, with the humeral head well centered on the glenoid fossa; flat, with flattening of the posterior glenoid; biconcave, with the humeral head in articulation with the posterior of two concavities, which were in the same plane; and pseudoglenoid, with the humeral head in articulation with the more posterior of two concavities, with retroversion and in a plane different from that of the anterior concavity. Kruskal-Wallis test was used to compare preoperative external rotation with four appearances of glenoid. RESULTS: Twenty-one children had concentric glenohumeral joints; seven children, flat glenohumeral joints; 19 children, biconcave glenoid; and 17 children, pseudoglenoid. Median passive external rotation was -20 degrees for patients with pseudoglenoid, -10 degrees for those with flat or biconcave glenoids, and 0 degrees for those with concentric glenoids. Presence and type of glenoid deformity were significantly associated with severity of internal rotation contracture (P <.001). CONCLUSION: Consistent patterns of glenohumeral joint deformity in brachial plexus birth palsy were identified and correlated with severity of internal rotation contracture.