Pragya A. Dang

Effect of computerized order entry with integrated decision support on the growth of outpatient procedure volumes: seven-year time series analysis.

PURPOSE To determine the effect of a computerized radiology order entry (ROE) and decision support (DS) system on growth rate of outpatient computed tomography (CT), magnetic resonance (MR) imaging, and ultrasonography (US) procedure volumes over time at a large metropolitan academic medical center. MATERIALS AND METHODS Institutional review board approval was obtained for this study of deidentified aggregate administrative data. The research was compliant with HIPAA; informed consent was waived. This was a retrospective study of outpatient advanced imaging utilization before, during, and after implementation of a Web-based ROE and DS system. Dependent variables were the quarterly volumes of outpatient CT, MR imaging, and US examinations from quarter 4 of 2000 through quarter 4 of 2007. Outpatient visits during each quarter were included as control variables. These data were analyzed as three separate time series with piecewise linear regression for simultaneous estimation of quarterly examination volume trends before and after ROE and DS system implementation. This procedure was repeated with log-transformed quarterly volumes to estimate percentage growth rates. RESULTS There was a significant decrease in CT volume growth (274 per quarter) and growth rate (2.75% per quarter) after ROE and DS system implementation (P < .001). For MR imaging, growth rate decreased significantly (1.2%, P = .016) after ROE and DS system implementation; however, there was no significant change in quarterly volume growth. With US, quarterly volume growth (n = 98, P = .014) and growth rate (1.3%, P = .001) decreased significantly after ROE implementation. These changes occurred during a steady growth in clinic visit volumes in the associated referral practices. CONCLUSION Substantial decreases in the growth of outpatient CT and US procedure volume coincident with ROE implementation (supplemented by DS for CT) were observed. The utilization of outpatient MR imaging decreased less impressively, with only the rate of growth being significantly lower after interventions were in effect.

Addition of Tomosynthesis to Conventional Digital Mammography: Effect on Image Interpretation Time of Screening Examinations

PURPOSE To determine the effect of implementing a screening tomosynthesis program on real-world clinical performance by quantifying differences between interpretation times for conventional screening mammography and combined tomosynthesis and mammography for multiple participating radiologists with a wide range of experience in a large academic center. MATERIALS AND METHODS In this HIPAA-compliant, institutional review board-approved study, 10 radiologists prospectively read images from screening digital mammography or screening combined tomosynthesis and mammography examinations for 1-hour-long uninterrupted sessions. Images from 3665 examinations (1502 combined and 2163 digital mammography) from July 2012 to January 2013 were interpreted in at least five sessions per radiologist per modality. The number of cases reported during each session was recorded for each reader. The experience level for each radiologist was also correlated to the average number of cases reported per hour. Analysis of variance was used to assess the number of studies interpreted per hour. A linear regression model was used to evaluate correlation between breast imaging experience and time taken to interpret images from both modalities. RESULTS The mean number of studies interpreted in hour was 23.8 ± 0.55 (standard deviation) (range, 14.4-40.4) for combined tomosynthesis and mammography and 34.0 ± 0.55 (range, 20.4-54.3) for digital mammography alone. A mean of 10.2 fewer studies were interpreted per hour during combined tomosynthesis and mammography compared with digital mammography sessions (P < .0001). The mean interpretation time was 2.8 minutes ± 0.9 (range, 1.5-4.2 minutes) for combined tomosynthesis and mammography and 1.9 minutes ± 0.6 (range, 1.1-3.0) for digital mammography; interpretation time with combined tomosynthesis and mammography was 0.9 minute longer (47% longer) compared with digital mammography alone (P < .0001). With the increase in years of breast imaging experience, the overall additional time required to read images from combined tomosynthesis and mammography examinations decreased (R(2) = 0.52, P = .03). CONCLUSION Addition of tomosynthesis to mammography results in increased time to interpret images from screening examinations compared with time to interpret images from conventional digital mammography alone.

Informatics in Radiology: Render: An Online Searchable Radiology Study Repository

Radiology departments are a rich source of information in the form of digital radiology reports and images obtained in patients with a wide spectrum of clinical conditions. A free text radiology report and image search application known as Render was created to allow users to find pertinent cases for a variety of purposes. Render is a radiology report and image repository that pools researchable information derived from multiple systems in near real time with use of (a) Health Level 7 links for radiology information system data, (b) periodic file transfers from the picture archiving and communication system, and (c) the results of natural language processing (NLP) analysis. Users can perform more structured and detailed searches with this application by combining different imaging and patient characteristics such as examination number; patient age, gender, and medical record number; and imaging modality. Use of NLP analysis allows a more effective search for reports with positive findings, resulting in the retrieval of more cases and terms having greater relevance. From the retrieved results, users can save images, bookmark examinations, and navigate to an external search engine such as Google. Render has applications in the fields of radiology education, research, and clinical decision support.

Extraction of Recommendation Features in Radiology with Natural Language Processing: Exploratory Study

OBJECTIVE The purposes of this study were to validate a natural language processing program for extraction of recommendation features, such as recommended time frames and imaging technique, from electronic radiology reports and to assess patterns of recommendation features in a large database of radiology reports. MATERIALS AND METHODS This study was performed on a radiology reports database covering the years 1995-2004. From this database, 120 reports with and without recommendations were selected and randomized. Two radiologists independently classified these reports according to presence of recommendations, time frame, and imaging technique suggested for follow-up or repeated examinations. The natural language processing program then was used to classify the reports according to the same criteria used by the radiologists. The accuracy of classification of recommendation features was determined. The program then was used to determine the patterns of recommendation features for different patients and imaging features in the entire database of 4,211,503 reports. RESULTS The natural language processing program had an accuracy of 93.2% (82/88) for identifying the imaging technique recommended by the radiologists for further evaluation. Categorization of recommended time frames in the reports with the 88 recommendations obtained with the program resulted in 83 (94.3%) accurate classifications and five (5.7%) inaccurate classifications. Recommendations of CT were most common (27.9%, 105,076 of 376,918 reports) followed by those for MRI (17.8%). In most (85.4%, 322,074/376,918) of the reports with imaging recommendations, however, radiologists did not specify the time frame. CONCLUSION Accurate determination of recommended imaging techniques and time frames in a large database of radiology reports is possible with a natural language processing program. Most imaging recommendations are for high-cost but more accurate radiologic studies.

Natural Language Processing Using Online Analytic Processing for Assessing Recommendations in Radiology Reports

PURPOSE The study purpose was to describe the use of natural language processing (NLP) and online analytic processing (OLAP) for assessing patterns in recommendations in unstructured radiology reports on the basis of patient and imaging characteristics, such as age, gender, referring physicians, radiology subspecialty, modality, indications, diseases, and patient status (inpatient vs outpatient). MATERIALS AND METHODS A database of 4,279,179 radiology reports from a single tertiary health care center during a 10-year period (1995-2004) was created. The database includes reports of computed tomography, magnetic resonance imaging, fluoroscopy, nuclear medicine, ultrasound, radiography, mammography, angiography, special procedures, and unclassified imaging tests with patient demographics. A clinical data mining and analysis NLP program (Leximer, Nuance Inc, Burlington, Massachusetts) in conjunction with OLAP was used for classifying reports into those with recommendations (I(REC)) and without recommendations (N(REC)) for imaging and determining I(REC) rates for different patient age groups, gender, imaging modalities, indications, diseases, subspecialties, and referring physicians. In addition, temporal trends for I(REC) were also determined. RESULTS There was a significant difference in the I(REC) rates in different age groups, varying between 4.8% (10-19 years) and 9.5% (>70 years) (P <.0001). Significant variations in I(REC) rates were observed for different imaging modalities, with the highest rates for computed tomography (17.3%, 100,493/581,032). The I(REC) rates varied significantly for different subspecialties and among radiologists within a subspecialty (P < .0001). For most modalities, outpatients had a higher rate of recommendations when compared with inpatients. CONCLUSION The radiology reports database analyzed with NLP in conjunction with OLAP revealed considerable differences between recommendation trends for different imaging modalities and other patient and imaging characteristics.

Use of Radcube for Extraction of Finding Trends in a Large Radiology Practice

The purpose of our study was to demonstrate the use of Natural Language Processing (Leximer), along with Online Analytic Processing, (NLP-OLAP), for extraction of finding trends in a large radiology practice. Prior studies have validated the Natural Language Processing (NLP) program, Leximer for classifying unstructured radiology reports based on the presence of positive radiology findings (FPOS) and negative radiology findings (FNEG). The FPOS included new relevant radiology findings and any change in status from prior imaging. Electronic radiology reports from 1995–2002 and data from analysis of these reports with NLP-Leximer were saved in a data warehouse and exported to a multidimensional structure called the Radcube. Various relational queries on the data in the Radcube were performed using OLAP technique. Thus, NLP-OLAP was applied to determine trends of FPOS in different radiology exams for different patient and examination attributes. Pivot tables were exported from NLP-OLAP interface to Microsoft Excel for statistical analysis. Radcube allowed rapid and comprehensive analysis of FPOS and FNEG trends in a large radiology report database. Trends of FPOS were extracted for different patient attributes such as age groups, gender, clinical indications, diseases with ICD codes, patient types (inpatient, ambulatory), imaging characteristics such as imaging modalities, referring physicians, radiology subspecialties, and body regions. Data analysis showed substantial differences between FPOS rates for different imaging modalities ranging from 23.1% (mammography, 49,163/212,906) to 85.8% (nuclear medicine, 93,852/109,374; p < 0.0001). In conclusion, NLP-OLAP can help in analysis of yield of different radiology exams from a large radiology report database.

Breast Cancer Characteristics Associated with 2D Digital Mammography versus Digital Breast Tomosynthesis for Screening-detected and Interval Cancers

Purpose To determine whether the rates and tumor characteristics of screening-detected and interval cancers differ for two-dimensional digital mammography (DM) versus digital breast tomosynthesis (DBT) mammography. Materials and Methods Consecutive screening mammograms from January 2009 to February 2011 (DM group, before DBT integration) and from January 2013 to February 2015 (DBT group, after complete DBT integration) were reviewed. Cancers were considered screening detected if diagnosed within 365 days of a positive screening examination and interval if diagnosed within 365 days of a negative screening examination. Z tests were used to compare cancers on DM versus DBT examinations. Results A total of 948 breast cancers were diagnosed after 78 385 DM and 76 896 DBT examinations. Although the overall rate of screening-detected cancers was similar with DM and DBT (5.0 vs 5.0 per 1000 examinations, P = .98), a higher proportion of screening-detected cancers were invasive rather than in situ with DBT (74.2% [287 of 387] vs 66.0% [260 of 394], P = .01). There were no significant differences in tumor characteristics, including size at pathologic examination, grade, hormone receptor status, and nodal status, between the screening-detected invasive cancers on DM versus DBT (P = .09-.99). The rate of interval cancers was similar with DM and DBT (1.1 vs 1.1 per 1000 examinations, P = .84). Compared with symptomatic interval cancers, magnetic resonance imaging-detected interval cancers were more likely to be minimal cancers. Conclusion The overall rates of screening-detected and interval cancers are similar with DM and DBT, but a higher proportion of screening-detected cancers are invasive rather than in situ with DBT.

Case 29-2016

Dr. Alyssa R. Letourneau: A 53-year-old woman with systemic lupus erythematosus with associated nephritis and chronic renal insufficiency was seen in the gynecology clinic of this hospital because of pain and a lump in the left breast. The patient had been in her usual health until 4 months before this presentation, when she noted a small, tender lump in the left breast on self-examination. Evaluation by her primary care physician revealed a firm, slightly mobile mass (measuring 5 mm in greatest dimension) in the upper inner quadrant of the left breast. The skin overlying the mass appeared normal, and there was no nipple discharge or axillary lymphadenopathy. The right breast and the remainder of the physical examination were normal. Three days earlier, routine laboratory tests had been performed by her nephrologist; the test results are shown in Table 1. Dr. Pragya A. Dang: Three days later, combined digital mammography and tomosynthesis of the left breast was negative, with no suspicious masses, areas of architectural distortion, or microcalcifications (Fig. 1). Ultrasonography targeted to the 10 o’clock position in the left breast revealed a superficial, hyperechoic, oval mass (measuring 6 mm in greatest dimension) with circumscribed margins that was located 5 cm from the nipple, in the dermis. The radiologic differential diagnosis included a sebaceous cyst, and the mass was thought to be probably benign. A plan was made to perform follow-up imaging in 6 months. Dr. Letourneau: Two months later, the patient was seen for routine follow-up in the nephrology and rheumatology clinics of this hospital. She reported fatigue, nausea, and epigastric pain. Mild epigastric tenderness was present; the remainder of the physical examination was normal. Laboratory test results are shown in Table 1. One month later, computed tomography of the abdomen and pelvis, performed without the administration of contrast material, revealed no evidence of pancreatitis; there was a new, indeterminate, hyperdense lesion (measuring 1.9 cm in greatest dimension) in the upper pole of the left kidney. Four months after the patient’s initial presentation, she was seen in the gynecology clinic of this hospital for a routine annual examination. She reported that pain in the left breast had developed 5 days earlier and that she had noted a lump in the upper outer quadrant. The pain had been persistent, was present throughout the breast, was worst near the nipple, and was unaffected by movement or change in position. From the Departments of Medicine (K.T.J., A.R.L.), Radiology (P.A.D.), Surgi‐ cal Oncology (M.C.S.), and Pathology (T.M.G.), Massachusetts General Hospi‐ tal, and the Departments of Medicine (K.T.J., A.R.L.), Radiology (P.A.D.), Sur‐ gery (M.C.S.), and Pathology (T.M.G.), Harvard Medical School — both in Boston.

Case 29-2016: A 53-Year-Old Woman with Pain and a Mass in the Breast

Dr. Alyssa R. Letourneau: A 53-year-old woman with systemic lupus erythematosus with associated nephritis and chronic renal insufficiency was seen in the gynecology clinic of this hospital because of pain and a lump in the left breast. The patient had been in her usual health until 4 months before this presentation, when she noted a small, tender lump in the left breast on self-examination. Evaluation by her primary care physician revealed a firm, slightly mobile mass (measuring 5 mm in greatest dimension) in the upper inner quadrant of the left breast. The skin overlying the mass appeared normal, and there was no nipple discharge or axillary lymphadenopathy. The right breast and the remainder of the physical examination were normal. Three days earlier, routine laboratory tests had been performed by her nephrologist; the test results are shown in Table 1. Dr. Pragya A. Dang: Three days later, combined digital mammography and tomosynthesis of the left breast was negative, with no suspicious masses, areas of architectural distortion, or microcalcifications (Fig. 1). Ultrasonography targeted to the 10 o’clock position in the left breast revealed a superficial, hyperechoic, oval mass (measuring 6 mm in greatest dimension) with circumscribed margins that was located 5 cm from the nipple, in the dermis. The radiologic differential diagnosis included a sebaceous cyst, and the mass was thought to be probably benign. A plan was made to perform follow-up imaging in 6 months. Dr. Letourneau: Two months later, the patient was seen for routine follow-up in the nephrology and rheumatology clinics of this hospital. She reported fatigue, nausea, and epigastric pain. Mild epigastric tenderness was present; the remainder of the physical examination was normal. Laboratory test results are shown in Table 1. One month later, computed tomography of the abdomen and pelvis, performed without the administration of contrast material, revealed no evidence of pancreatitis; there was a new, indeterminate, hyperdense lesion (measuring 1.9 cm in greatest dimension) in the upper pole of the left kidney. Four months after the patient’s initial presentation, she was seen in the gynecology clinic of this hospital for a routine annual examination. She reported that pain in the left breast had developed 5 days earlier and that she had noted a lump in the upper outer quadrant. The pain had been persistent, was present throughout the breast, was worst near the nipple, and was unaffected by movement or change in position. From the Departments of Medicine (K.T.J., A.R.L.), Radiology (P.A.D.), Surgi‐ cal Oncology (M.C.S.), and Pathology (T.M.G.), Massachusetts General Hospi‐ tal, and the Departments of Medicine (K.T.J., A.R.L.), Radiology (P.A.D.), Sur‐ gery (M.C.S.), and Pathology (T.M.G.), Harvard Medical School — both in Boston.

CASE RECORDS of the MASSACHUSETTS GENERAL HOSPITAL. Case 29-2016. A 53-Year-Old Woman with Pain and a Mass in the Breast.

Dr. Alyssa R. Letourneau: A 53-year-old woman with systemic lupus erythematosus with associated nephritis and chronic renal insufficiency was seen in the gynecology clinic of this hospital because of pain and a lump in the left breast. The patient had been in her usual health until 4 months before this presentation, when she noted a small, tender lump in the left breast on self-examination. Evaluation by her primary care physician revealed a firm, slightly mobile mass (measuring 5 mm in greatest dimension) in the upper inner quadrant of the left breast. The skin overlying the mass appeared normal, and there was no nipple discharge or axillary lymphadenopathy. The right breast and the remainder of the physical examination were normal. Three days earlier, routine laboratory tests had been performed by her nephrologist; the test results are shown in Table 1. Dr. Pragya A. Dang: Three days later, combined digital mammography and tomosynthesis of the left breast was negative, with no suspicious masses, areas of architectural distortion, or microcalcifications (Fig. 1). Ultrasonography targeted to the 10 o’clock position in the left breast revealed a superficial, hyperechoic, oval mass (measuring 6 mm in greatest dimension) with circumscribed margins that was located 5 cm from the nipple, in the dermis. The radiologic differential diagnosis included a sebaceous cyst, and the mass was thought to be probably benign. A plan was made to perform follow-up imaging in 6 months. Dr. Letourneau: Two months later, the patient was seen for routine follow-up in the nephrology and rheumatology clinics of this hospital. She reported fatigue, nausea, and epigastric pain. Mild epigastric tenderness was present; the remainder of the physical examination was normal. Laboratory test results are shown in Table 1. One month later, computed tomography of the abdomen and pelvis, performed without the administration of contrast material, revealed no evidence of pancreatitis; there was a new, indeterminate, hyperdense lesion (measuring 1.9 cm in greatest dimension) in the upper pole of the left kidney. Four months after the patient’s initial presentation, she was seen in the gynecology clinic of this hospital for a routine annual examination. She reported that pain in the left breast had developed 5 days earlier and that she had noted a lump in the upper outer quadrant. The pain had been persistent, was present throughout the breast, was worst near the nipple, and was unaffected by movement or change in position. From the Departments of Medicine (K.T.J., A.R.L.), Radiology (P.A.D.), Surgi‐ cal Oncology (M.C.S.), and Pathology (T.M.G.), Massachusetts General Hospi‐ tal, and the Departments of Medicine (K.T.J., A.R.L.), Radiology (P.A.D.), Sur‐ gery (M.C.S.), and Pathology (T.M.G.), Harvard Medical School — both in Boston.