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Purpose: Previous studies demonstrated rapid growth in payments to nonradiologist providers (NRPs) for MRI and CT in their private offices. In this study, we re-examine the trends in these payments., Methods: The nationwide Medicare Part B master files from 2004 to 2016 were accessed. They provide payment data for all Current Procedural Terminology codes. Codes for MRI and CT were selected. Global and technical component claims were counted. Medicare specialty codes identified payments made to NRPs and radiologists, and place-of-service codes identified payments directed to their private offices., Results: Medicare MRI payments to NRPs peaked in 2006 at $247.7 million. As a result of the Deficit Reduction Act, there was a sharp drop to $189.5 million in 2007, eventually declining to $101.6 million by 2016 (-59% from peak in 2006). The NRP specialty groups with the highest payments for MRI ownership include orthopedists, neurologists, primary care physicians, and hospital-based specialists (pathology, physiatry, and hospitalists). Medicare CT payments to NRPs peaked in 2008 at $284.1 million and declined to $94.7 million in 2016 (-67% from peak). Cardiologists, primary care physicians, internal medicine specialists, urologists, and medical oncologists accounted for the most payments made to NRPs. Dollars paid to radiologists for private office MRI and CT dropped substantially since they peaked in 2006., Conclusions: NRP private offices (and radiology offices also) experienced massive decreases in Medicare payments for MRI and CT since peaking in 2006 and 2008, respectively. These trends suggest the financial viability of private office practice may be in jeopardy. However, certain recent policy changes could promote a resurgence., (Copyright © 2019 American College of Radiology. Published by Elsevier Inc. All rights reserved.)

Purpose: MRI and ultrasound (US) are effective diagnostic tools to evaluate extremities. In this study, we analyze utilization trends in musculoskeletal (MSK) US and MRI from 2003 to 2015 within the Medicare population., Methods: Our data sources were the Medicare Part B Physician/Supplier Procedure Summary Master Files for 2003 to 2015. They cover all Medicare fee-for-service enrollees (37.5 million in 2015). Current Procedural Terminology codes for nonvascular, nonspine joint MRI and extremity US were selected and volumes within these codes were determined. Medicare's physician specialty codes were used to identify provider specialty. We accounted for the 2011 code change that created both complete and limited US examinations., Results: Total Medicare joint MRI volume increased from 738,509 in 2003 to 1,131,503 in 2015 (+53%), although there was little change after 2007. Radiologist MRI share in 2015 was 93%, followed by orthopedic surgeons at 5%. Total MSK US volume grew from 96,235 in 2003 to 429,695 in 2015 (+347%). Radiologists' market share of US decreased from 65% in 2003 to 37% in 2015, with nonradiologists now representing a majority of ultrasound examinations. Multiple nonradiology subspecialties also exceed radiology in volume of complete ultrasounds., Conclusion: The potential negative impact of MSK US on MSK MRI volume is likely overestimated because MRI volume has remained stable. MSK ultrasound is increasingly utilized outside radiology. If radiologists want to maintain their market share as MSK imaging leaders, more emphasis should be placed on increasing their involvement and expertise in MSK US., (Copyright © 2017 American College of Radiology. Published by Elsevier Inc. All rights reserved.)

Background: Determining neurological level of injury (NLI) is of paramount importance after spinal cord injury (SCI), although its accuracy depends upon the reliability of the neurologic examination. Here, we determine if anatomic location of cervical cord injury by MRI (MRI level of injury) can predict NLI in the acute traumatic setting., Methods: A retrospective review was undertaken of SCI patients with macroscopic evidence of cervical cord injury from non-penetrating trauma, all of whom had undergone cervical spine MRI and complete neurologic testing. The recorded MRI information included cord lesion type (intra-axial edema, hemorrhage) and MRI locations of upper and lower lesion boundary, as well as lesion epicenter. Pearson correlation and Bland-Altman analyses were used to assess the relationship between MRI levels of injury and NLI., Results: All five MRI parameters, namely (1) upper and (2) lower boundaries of cord edema, (3) lesion epicenter, and (4) upper and (5) lower boundaries of cord hemorrhage demonstrated statistically significant, positive correlations with NLI. The MRI locations of upper and lower boundary of hemorrhage were found to have the strongest correlation with NLI (r = 0.72 and 0.61, respectively; p < 0.01). A weaker (low to moderate) correlation existed between lower boundary of cord edema and NLI (r = 0.30; p < 0.01). Upper boundary of cord hemorrhage on MRI demonstrated the best agreement with NLI (mean difference 0.03 ± 0.73; p < 0.01) by Bland-Altman analysis., Conclusions: MRI level of injury has the potential to serve as a surrogate for NLI in instances where the neurologic examination is either unavailable or unreliable.

Purpose: To evaluate gluteus medius and minimus tendon pathology and muscle atrophy in older individuals using MRI., Methods: A retrospective MRI study of 185 individuals was performed. The inclusion criterion was age ≥50. Exclusion criteria were hip surgery, fracture, infection, tumor, or inadequate image quality. Greater trochanteric bursitis was graded none, mild, moderate, or severe. Gluteus medius, gluteus minimus, and iliopsoas tendinopathy was graded normal, tendinosis, low-grade partial tear, high-grade partial tear, or full thickness tear. Gluteus medius, gluteus minimus, tensor fascia lata, and iliopsoas muscle atrophy was scored using a standard scale. Insertion site of tendinopathy and location of muscle atrophy were assessed. Descriptive and statistical analysis was performed., Results: There was increasing greater trochanteric bursitis and gluteus medius and minimus tendinopathy and atrophy with advancing age with moderate to strong positive associations (p < 0.0001) for age and tendinopathy, age and atrophy, bursitis and tendinopathy, and tendinopathy and atrophy for the gluteus medius and minimus. There is a weak positive association (p < 0.0001) for age and tensor fascia lata atrophy, and no statistically significant association between age and tendinopathy or between age and atrophy for the iliopsoas. Fisher's exact tests were statistically significant (p < 0.0001) for insertion site of tendon pathology and location of muscle atrophy for the gluteus medius., Conclusions: Gluteus medius and minimus tendon pathology and muscle atrophy increase with advancing age with progression of tendinosis to low-grade tendon tears to high-grade tendon tears. There is an associated progression in atrophy of these muscles, which may be important in fall-related hip fractures.

Purpose: To determine whether recent reimbursement cuts have resulted in a shift of outpatient MRI from private offices to hospital outpatient departments (HOPDs); and to study office MRI utilization trends among radiologists and other specialists., Methods: The Medicare Part B Physician/Supplier Procedure Summary Master Files were used. MRI codes were aggregated, and total MRI volumes from 2002 to 2012 were studied. Medicare place-of-service codes were used to identify studies performed in private offices and HOPDs and create trend lines. Specialty codes were used to categorize private office MRI users as radiologists, orthopedic surgeons, other physicians, and independent diagnostic testing facilities., Results: Medicare office and HOPD utilization of MRI (all specialties) rose rapidly from 2002 to 2006, reaching 2,727,807 in offices and 2,355,641 in HOPDs. Thereafter, office volume steadily declined, whereas HOPD volume steadily increased. By 2012, more studies were done in HOPDs than in offices. Over the entire period from 2002 and 2012, office MRI volume among radiologists increased 27%, compared with 216% among orthopedic surgeons and 124% among other physicians., Conclusions: Although the majority of Medicare outpatient MRI studies had previously been performed in private offices, recent years brought a shift, with more now being performed in HOPDs. This change will increase costs to payers, because reimbursements to HOPDs are generally higher than those to offices. Although radiologists perform the majority of MRI exams that are conducted in private offices, the rate of growth for such exams from 2002 to 2012 was considerably higher among orthopedic surgeons and other physicians than among radiologists., (Copyright © 2015 American College of Radiology. Published by Elsevier Inc. All rights reserved.)

Purpose: Diagnostic imaging services have been repeatedly targeted as a source of excess health care expenditure. In particular, MRI is considered a high-tech and high-cost imaging service that saw rapid increases in utilization in the early 2000s. However, the most recent trends in the utilization of MR are not known. The aim of this study was to quantify trends in MR utilization overall and by body system from 1998 to 2010 in the Medicare population., Methods: Medicare Part B data sets were obtained for 1998 to 2010 for all MR examinations performed in the Medicare population. Using Current Procedural Terminology codes, the total volume and utilization rates of all MR examinations were tabulated for each year of the study period. MR volume was then categorized by body system., Results: The utilization rate of MR examinations in the Medicare population was 73 per 1,000 beneficiaries in 1998, increased to a peak of 189 in 2008, and decreased to 183 in 2010. The compound annual growth rate from 1998 to 2008 was 10%. The utilization rate in 2010 represents a decrease of 3.1% from the 2009 utilization rate. The most frequently imaged body section in every year was the head, which accounted for 2,404,250 examinations in 2010, 37.3% of all MR examinations in that year., Conclusions: The overall MRI utilization rate sharply increased from 1998 until 2008 but then decreased in each of the next 2 years. A similar trend was noted for MR examinations performed in most body sections. These trends are likely to be the result of a number of possible causative factors., (Copyright © 2013 American College of Radiology. Published by Elsevier Inc. All rights reserved.)

Purpose: Evaluate the reliability and validity of a standardized reporting system designed to improve communication between the clinician and radiologist regarding likelihood of hepatocellular carcinoma (HCC)., Materials and Methods: The system assigns liver lesions into 1 of 5 categories of estimated likelihood of HCC: 1, <5%; 2, 5%-20%; 3, 21%-70%; 4, 71%-95%; 5, >95%. Six American Board of Radiology-certified radiologists reviewed 100 abdominal MRI studies (performed between September 2009 and June 2010 for HCC surveillance) blinded to the official reports and clinical information. Each reader recorded the highest category (1-5) assigned to any lesion per study. Reliability between readers was calculated by the Shrout-Fliess random sets intraclass correlation (ICC). To examine validity, original pretransplant reports from January 2009 to December 2010 were compared to pathology reports on liver explants. Sensitivities, specificities, predictive values, and receiver operating characteristic (ROC) curves were then produced., Results: The ICC for retrospective readings was 0.80, indicating very good reliability. Of 45 pathologically proven cases, 16 category 1 or 2 cases were all free of HCC (negative predictive value 100%). Five of nine category 3 cases contained HCC. Six of eight category 4 cases contained HCC (PPV 75%). All 12 category 5 cases contained HCC (positive predictive value 100%). The area underneath the ROC curve was 0.949. If categories 1 and 2 are considered negative and categories 3-5 considered positive, this achieves 100% sensitivity with 73% specificity., Conclusion: This standardized system for reporting likelihood of HCC, which is a forerunner of the recently introduced Liver Imaging Reporting and Data System, produces strong reliability and validity, while aiming to improve the clarity of clinical magnetic resonance imaging reports., (Copyright © 2013 AUR. Published by Elsevier Inc. All rights reserved.)

Purpose: To retrospectively determine whether benign exophytic renal masses can be distinguished from renal cell carcinoma (RCC) on the basis of angular interface at single-shot fast spin-echo (SE) T2-weighted magnetic resonance (MR) imaging., Materials and Methods: This retrospective study was compliant with HIPAA and was approved by the institutional review board. Patient informed consent was waived. A total of 162 exophytic (2 cm or greater) renal masses in 152 patients (103 men, 49 women; mean age, 58 years; age range, 23-85 years) were included. Two radiologists independently recorded the mass size and angular interface on single-shot fast SE T2-weighted MR images. Surgical pathologic report and MR follow-up were used as reference standards. Logistic regression analysis was used to examine the usefulness of these variables for differentiating benign masses from RCCs. Diagnostic performance was analyzed by comparing values for area under receiver operating characteristic curve (A(z)). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of angular interface for diagnosing benign masses were calculated. Reader agreement was assessed with kappa-weighted statistics and intraclass correlation coefficients (ICCs)., Results: Of 162 masses, 65 were benign, and 97 were RCCs. The sensitivity, specificity, PPV, NPV, and A(z) of angular interface for diagnosing benign masses were 78%, 100%, 100%, 87%, and 0.813, respectively. Angular interface (P < .001) was a significant predictor of benign renal mass but mass size (P = .66) was not. There was almost perfect interobserver agreement for mass size (ICC = 0.96) and angular interface (kappa = 0.91)., Conclusion: The presence of an angular interface with the renal parenchyma at single-shot fast SE T2-weighted MR imaging is a strong predictor of benignity in an exophytic renal mass 2 cm or greater in diameter with high specificity and diagnostic accuracy.

Purpose: The Deficit Reduction Act of 2005 (DRA) sharply reduced technical component payments for private office magnetic resonance imaging (MRI) and computed tomographic (CT) imaging. Although radiologists have no control over referrals, nonradiologist physicians (NRPs) can potentially make up for revenue shortfalls by self-referring more examinations. The purpose of this study was therefore to compare the effects of the DRA on the in-office MRI and CT practices of radiologists and NRPs., Materials and Methods: The nationwide Medicare Part B databases for 2002 to 2007 were studied. All MRI and CT codes were selected. Using Medicare physician specialty and place-of-service codes, examinations performed in private offices by radiologists were identified and compared with those performed by NRPs. Trends in procedure volume and payments were studied. The pre-DRA compound annual growth rates for 2002 to 2006 and the post-DRA one-year rates for 2007 are reported., Results: For MRI, radiologists' private office volume increased by 8.4% yearly from 2002 to 2006 but then dropped by 2.0% in 2007. Nonradiologist physicians' office volume increased by 24.8% yearly, then increased by another 7.6% in 2007. Office MRI payments to radiologists increased by 11.2% yearly from 2002 to 2006 but then dropped by 30.1% in 2007. Nonradiologist physicians' office MRI payments increased by 25.7% yearly, then dropped by 23.5% in 2007. For CT imaging, radiologists' private office volume increased by 11.2% yearly from 2002 to 2006 but then increased by only 2.9% in 2007. Nonradiologist physicians' office volume increased by 31.8% yearly, then increased by another 18.1% in 2007. Office CT payments to radiologists increased by 13.4% yearly from 2002 to 2006 but then dropped by 5.2% in 2007. Nonradiologist physicians' office CT payments increased by 34.9% yearly, then increased by another 8.3% in 2007., Conclusion: After the DRA took effect, office MRI volume dropped among radiologists but increased among NRPs. Payments for MRI to both dropped, but the percentage decrease to radiologists was greater. Office CT volume increased slightly among radiologists but increased much more among NRPs on a percentage basis. Payments for CT imaging to radiologists dropped, but they increased to NRPs. These results suggest that NRPs may be able to ameliorate the effects of the DRA by increasing self-referral. These trends are of concern and should be scrutinized in future years.

Objective: The purpose of this study was to compare the diagnostic accuracy of MRI, MR arthrography, and ultrasound for the diagnosis of rotator cuff tears through a meta-analysis of the studies in the literature., Materials and Methods: Articles reporting the sensitivities and specificities of MRI, MR arthrography, or ultrasound for the diagnosis of rotator cuff tears were identified. Surgical (open and arthroscopic) reference standard was an inclusion criterion. Summary statistics were generated using pooled data. Scatterplots of the data sets were plotted on a graph of sensitivity versus (1 - specificity). Receiver operating characteristic (ROC) curves were generated., Results: Sixty-five articles met the inclusion criteria for this meta-analysis. In diagnosing a full-thickness tear or a partial-thickness rotator cuff tear, MR arthrography is more sensitive and specific than either MRI or ultrasound (p < 0.05). There are no significant differences in either sensitivity or specificity between MRI and ultrasound in the diagnosis of partial- or full-thickness rotator cuff tears (p > 0.05). Summary ROC curves for MR arthrography, MRI, and ultrasound for all tears show the area under the ROC curve is greatest for MR arthrography (0.935), followed by ultrasound (0.889) and then MRI (0.878); however, pairwise comparisons of these curves show no significant differences between MRI and ultrasound (p > 0.05)., Conclusion: MR arthrography is the most sensitive and specific technique for diagnosing both full- and partial-thickness rotator cuff tears. Ultrasound and MRI are comparable in both sensitivity and specificity.

Background: In order to retrospectively determine the frequency of dilated cisterna chyli (CC) on MR images in patients with cirrhosis, and to assess its value as a simple diagnostic imaging sign of uncompensated cirrhosis., Methods: Study population included 257 patients (149 with pathologically proved cirrhosis and 108 control subjects without the history of chronic liver diseases) who had 1.5 T MR imaging. Cirrhosis patients were divided into compensated and uncompensated groups. Three independent observers qualitatively evaluated the visibility of CC 2 mm or greater in transverse diameter, identified as a tubular structure with fluid signal intensity. CC diameters greater than 6 mm were defined as dilated. Statistical analysis was performed by Student t-test and interobserver agreement via intraclass correlation coefficient., Results: CCs with diameter 2 mm or more were recorded in 113 of 149 (76%) cirrhotic patients and 15 of 108 (14%) control subjects (P < 0.001). Dilated CCs were significantly more frequent in uncompensated than compensated cirrhotic patients (54% vs 5%, P < 0.001). The sensitivity, specificity, accuracy, and positive predictive value of dilated CC for uncompensated cirrhosis were 54%, 98%, 80%, and 96%, respectively., Conclusions: Dilated CC can be used as a simple and specific sign complimentary to other findings of uncompensated cirrhosis.

Background: We retrospectively evaluate the potential protective influence of patent paraumblical vein (PUV) collaterals against portal vein (PV) thrombosis and reduced PV diameter in candidates for orthotopic liver transplant (OLT) METHODS: Dynamic 3D contrast-enhanced MRI at 1.5T was obtained in 309 patients with cirrhosis without evidence of malignancy. All MR studies were reviewed by one reader for PUV collaterals, PV thrombosis and PV diameter. Statistical analysis was performed by Fisher exact tests; 50 selected studies were reviewed independently by two additional readers to determine interobserver agreement via intraclass correlation coefficient (ICC)., Results: Patent PUV was noted in 119 of 309 patients (38.5%). Mean PV diameter was 13.4 +/- 3.0 mm in patients with PUV compared with 11.3 +/- 3.6 mm without PUV (P < 0.01). Main PV thrombosis was present in 13 of 309 patients (4.2%) and significantly more frequent in those without PUV than with PUV (6.3% vs. 0.8%, P < 0.05). ICC indicated almost perfect agreement among three readers for presence of PUV collaterals (ICC = 0.91) and PV thrombosis (ICC = 0.96)., Conclusion: Our results suggest that patients with patent PUV appear less likely to develop main PV thrombosis or small PV diameter, suggesting a protective effect of PUV on PV patency.

Objective: The purpose of this study was to determine the frequency of abnormal MR signal intensity in soft tissues and osseous structures in association with surgically proven meniscal tears., Materials and Methods: Seventy patients underwent 1.5-T MRI of the knee and arthroscopy within 3 months. MR images were reviewed by two radiologists for parameniscal cysts, bowing and edema around the collateral ligament, meniscal extrusion, cartilage loss, and nonlinear and linear subchondral marrow edema. The findings were correlated with the arthroscopic findings. The positive predictive value (PPV), sensitivity, and specificity of indirect signs were calculated., Results: Fifty-three medial and 28 lateral meniscal tears were found at arthroscopy. The PPV of indirect signs of meniscal tear was 0.17-1.00 for reader 1 and 0.37-1.00 for reader 2. The PPV of parameniscal cysts was 1.00 for medial and lateral meniscal tears for both readers. The specificity and PPV of periligamentous edema and cruciate ligament bowing for medial meniscal tear were 0.94 and 0.98 for both readers, 0.88 and 0.94 for reader 1, and 0.94 and 0.97 for reader 2. The specificity and PPV of subchondral marrow edema for medial meniscal tear were 0.88 and 0.96 for reader 1 and 0.94 and 0.97 for reader 2 and for lateral meniscal tear were 0.98 and 0.92 for reader 1 and 1.00 and 1.00 for reader 2. The specificity and PPV of linear subchondral marrow edema for medial meniscal tear were 0.94 and 0.97 for reader 1 and 1.00 and 1.00 for reader 2. For lateral meniscal tear, the values were 0.98 and 0.89 for reader 1 and 1.00 and 1.00 for reader 2. The specificity and PPV of nonlinear subchondral marrow edema for medial meniscal tear were 0.94 and 0.89 for reader 1 and 1.00 and 1.00 for reader 2. For lateral meniscal tear, the values were 0.89 and 0.97 for reader 1 and 1.00 and 1.00 for reader 2. The specificity and PPV of cartilage loss for medial meniscal tear were 0.88 and 0.94 for reader 1 and 0.88 and 0.93 for reader 2. For lateral meniscal tear, the values were 0.85 and 0.56 for reader 1 and 0.97 and 0.80 for reader 2., Conclusion: Indirect MRI signs occur in association with meniscal tears and can aid diagnostic confidence when the MRI meniscal appearance is equivocal.

Study Design: Cross-sectional retrospective review of 539 patients with lumbar spine magnetic resonance imaging (MRI)., Objectives: The purpose of this study was to determine the prevalence of lumbar posterior element interspinous bursitis (Baastrup disease) and to measure the association with degenerative disc disease findings, deformities, age, and gender in symptomatic people., Summary of Background Data: Case reports and small case series describing Baastrup disease exist. The prevalence of Baastrup disease on MRI and association with other degenerative-related findings has not been reported., Methods: The study group consisted of 539 patients (51% males, 49% females; age range, 7-89 years old) undergoing routine lumbar spine MRI using sagittal T1-weighted, sagittal T2-weighted, and axial T2-weighted pulse sequences. Retrospective consensus review by 2 observers evaluated for the presence of: fluid intervening between consecutive spinous processes (criterion for Baastrup disease), disc degeneration (spondylosis) and contour abnormalities (bulges, herniations), marrow endplate signal alteration (Modic changes), central canal stenosis, lordosis, scoliosis, and displacement (anterolisthesis, retrolisthesis). Statistical analyses were descriptive statistics and determining associations between these MRI findings and Baastrup disease (using chi and Wilcoxon rank sums)., Results: Lumbar interspinous bursitis (Baastrup disease) was present in 8.2% (44 of 539) of the study population. There were associations between the presence of Baastrup disease and age (P = 0.001), central canal stenosis (P = 0.0013), disc bulging (P = 0.0341), and anterolisthesis (P = 0.0429). There were not associations between Baastrup disease and disc degeneration, disc herniation, endplate findings, retrolisthesis, scoliosis, lordosis, or gender., Conclusion: Lumbar interspinous bursitis (Baastrup disease) is uncommon but not infrequent in symptomatic patients undergoing lumbar spine MRI. Patients with MRI evident Baastrup disease tend to be older, have central canal stenosis, bulging discs, and anterolisthesis. Further investigations determining the clinical significance of this finding are necessary.

Purpose: The current study explores the substitution of ultrasound (US) for magnetic resonance imaging (MRI) of musculoskeletal (MSK) disorders by describing the recent use and costs of MSK imaging in the Medicare population, projecting these trends from 2006 to 2020, and estimating cost-savings involved in substituting MSK US for MSK MRI, when appropriate., Methods: The study used government-published data sets and de-identified Radiology Information System records exempt from institutional review board approval. From 1 year's MSK MRI records (n = 3,621), the proportion of cases in which US could be substituted for MRI was estimated. The use rates for 4 modalities of MSK imaging and average costs were determined from government Medicare data sets from 1996 to 2005. Regression analysis was used to project use rates from 2006 to 2020. The effect on costs of substitution was calculated., Results: For the Medicare population, although there has been a moderate overall increase (25.7%) in MSK imaging, MSK MRI has increased 353.5% from 1996 to 2005. Projected MSK imaging costs in 2020 are $3.6 billion, of which $2.0 billion will be for MRI. A study of 3,621 MSK MRI reports indicates that 45.4% of primary diagnoses and 30.6% of all diagnoses could have been made with MSK US. The substitution of MSK US for MSK MRI, when appropriate, would lead to savings of more than $6.9 billion in the period from 2006 to 2020., Conclusion: MRI MSK use has grown substantially from 1996 to 2005. The substitution of MSK US, when appropriate, would lead to large cost-savings for Medicare.

Purpose: To study growth trends in the ownership of magnetic resonance imaging (MRI) examinations by nonradiologist physicians who either own the equipment outright or are involved in scan leasing arrangements., Methods and Materials: Medicare Part B data sets from 2000 through 2005 were reviewed, and procedure codes for MRI examinations were selected. The focus was on only those procedures performed at nonhospital, private-office facilities. Using Medicare's physician specialty codes, all such studies were categorized according to the specialties of the physicians who performed them. Ownership was determined by including only those claims for global or technical-component-only reimbursement. Physicians owning or leasing MRI facilities would use one or the other of these two types of claims. Professional-component-only claims were not included. Procedure volumes and growth trends were compared among radiologists and other specialists., Results: From 2000 to 2005, private-office MRI examinations performed by radiologists increased by 83%. During the same period, private-office MRI examinations performed by nonradiologist physicians, either through owning or leasing the equipment, increased by 254%. Excluding studies performed by independent diagnostic testing facilities (for which physician ownership cannot be determined), nonradiologists' share of the private-office MRI market rose from 11% in 2000 to 20% in 2005. The nonradiologic specialties most actively involved in performing MRI were orthopedic surgery (161,296 Medicare studies in 2005), neurology (63,363 studies), primary care (58,092 studies), internal medicine subspecialties (34,317 studies), and neurosurgery (20,712 studies)., Conclusions: In the private-office setting in 2005, radiologists performed most MRI examinations. However, the growth rate from 2000 to 2005 among nonradiologist physicians was far higher, 254% compared with 83% among radiologists. Because scans performed by nonradiologists through ownership or leasing are subject to self-referral, the much more rapid growth among those physicians should be of concern to policymakers and payers.

Purpose: To retrospectively evaluate the sensitivity, specificity, and positive and negative predictive values of steady-state free-precession (SSFP) survey MRI of the abdomen., Materials and Methods: A total of 375 consecutive outpatients underwent abdominal MRI at 1.5T. Excluding diffuse metastatic disease, 110 patients had at least one other clinically important finding. The SSFP survey included contiguous 5-mm-thick axial, sagittal, and coronal slices (total 90 slices) obtained during a total of 90 seconds of free breathing. Studies were reviewed by two experienced MRI readers independently, randomized, blinded, and at different sittings. The chi-squared test was used to compare SSFP to full MRI for showing clinically important findings. In a subset of 30 patients, confidence intervals (CI) were calculated to compare the accuracy of SSFP and full MRI as predictors of biopsy result., Results: SSFP detected 87.3% of clinically important findings and 93.3% of malignancies reported on the full MRI, with a 1.5% false-positive rate. Significant association was shown between SSFP and full MRI for clinically important findings (P < 0.0001). Compared to biopsy, accuracy of SSFP was high (85% +/- 12.7%), though not as high as full MRI (93.3% +/- 8.8%)., Conclusion: SSFP provides a rapid survey of the abdomen, with good sensitivity and few false positives.

Background: We prospectively examined unenhanced MR imaging findings in relation to pathologic fibrosis, inflammation and steatosis in patients with compensated chronic hepatitis C viral infection (HCV)., Methods: Unenhanced MRI at 1.5 T was obtained within one month of core liver biopsy in 64 consecutive candidates for antiviral therapy for compensated HCV. Two pathologists independently graded inflammatory activity index (HAI) and steatosis, and staged fibrosis (grades 0-6). Morphologic MRI findings of cirrhosis, periportal lymph nodes, and MR fat signal ratio from dual gradient echo images were assessed independently by two radiologists blinded to clinical data. MRI and laboratory liver function results were correlated with pathologic results, using Spearman correlation coefficient and stepwise multiple regression., Results: MR fat signal ratio correlation coefficient with pathologic steatosis was 0.71 (p < 0.0001). Coefficients with fibrosis stage were highest for surface nodularity (r (s) = 47, p < 0.0001) and expanded gallbladder fossa (r (s) = 0.42, p = 0.0006). Coefficients with HAI were highest for lymph node size (r (s) = 0.355, p = 0.0040), surface nodularity (r = 0.47, p < 0.0001), expanded gallbladder fossa (r = 0.332, p = 0.0073), and caudate/right lobe ratio (r = 0.326, p = 0.0110). Combined lab and MRI variables provided the best prediction of fibrosis stage (r (2) = 0.656) and HAI (r (2) = 0.597)., Conclusions: A combination of MRI and laboratory findings was most predictive of fibrosis and inflammation.

Objective: Our objective was to determine the association between size and chronicity of full-thickness supraspinatus tendon tears with subscapularis tendon abnormalities on MRI., Materials and Methods: One hundred forty-two MRI examinations with full-thickness supraspinatus tendon tears were categorized on the basis of the supraspinatus muscle (SS): normal muscle (SS(normal)), suggesting a recent or small tear; reduced muscle bulk without fatty atrophy (SS(volume loss)); and those with fatty atrophy, suggesting a large or chronic tear (SS(fatty atrophy)). Subscapularis tendon abnormalities, the subcoracoid interval, and subcortical bone marrow edema in the lesser tuberosity and coracoid process were recorded., Results: The mean size of supraspinatus tendon tears in the SS(normal) (n = 45) group was 8.5 mm, 16.6 mm in SS(volume loss) (n = 53), and 29 mm in the SS(fatty atrophy) group (n = 44). Subscapularis tendon abnormality was identified in 22% of SS(normal) patients, 61% of SS(volume loss), and 86% of the SS(fatty atrophy) group (p < 0.001). There was moderate correlation between chronicity of supraspinatus tendon tears and subscapularis tendon abnormality (r = 0.47; p < 0.0001), with no correlation between the subcoracoid interval and abnormalities of the subscapularis tendon. There was moderate correlation between chronicity of supraspinatus tendon tears and bone marrow changes in the lesser tuberosity (r = 0.44; p < 0.0001)., Conclusion: Subscapularis tendon abnormality is related to chronicity of supraspinatus tendon tears. Bone marrow edema in the lesser tuberosity with a subscapularis tendon abnormality suggests increased stress at the subscapularis tendon insertion with chronicity of full-thickness supraspinatus tendon tears. Lack of correlation with the subcoracoid interval indicates that anterior instability may be a more important contributing factor to subscapularis tendon abnormalities than static subcoracoid impingement in the setting of a full-thickness supraspinatus tendon tear.

Purpose: There is considerable conflict between radiologists and cardiologists over who has the experience and knowledge to perform computed tomography (CT) and magnetic resonance imaging (MRI) of the cardiovascular (CV) system. The purpose of this study was to determine the relative roles of the different specialties in these procedures., Method and Materials: The nationwide 2003 Medicare Physician Supplier Procedure Summary Master Files were used to study all 8 codes for CT angiography and all 12 codes for magnetic resonance angiography and MRI of the heart. The database provides information on the number of studies performed in each code and the specialties of the physician providers. All professional component and global claims were tabulated, but technical-component-only claims were excluded because that would have led to double counting studies., Results: In 2003, in the Medicare fee-for-service population, a total of 266,142 CV CT studies were performed. Radiologists performed 257,581 (96.8%), and cardiologists performed 1,246 (0.5%). Primary care physicians (PCPs) and radiation oncologists each performed more of these studies than cardiologists: 1,879 and 1,389, respectively. Independent diagnostic testing facilities (IDTFs) and multispecialty groups together performed 2,398 (0.9%); although Medicare lists each of them as a medical "specialty," the actual specialty of a provider cannot be determined. A total of 110,743 CV MRI studies were performed. Radiologists did 100,788 (91.0%), and cardiologists did 3,257 (2.9%). In addition, IDTFs and multispecialty groups together performed 4,644, PCPs 753, and radiation oncologists 537., Conclusion: Cardiologists had only minimal roles in CV CT and MRI in 2003. Their procedure volume was so small that it raises a question as to whether they could be gaining meaningful experience or providing meaningful training to fellows. Radiologists strongly dominated in the use of these modalities for imaging CV structures.

Purpose: To evaluate the morphology and location of vertebral endplate changes, and to analyze their association with age, gender, and body mass index (BMI)., Design and Patients: At 1.5 T (T1-weighted, T2-weighted/STIR) 100 lumbar spines were evaluated separately by three observers. The readers classified the endplate bone marrow abnormalities on sagittal MR images according to the definitions of Modic et al. Findings were localized by disc segment; whether in the upper and/or lower endplate; and within each endplate divided into 15 segments. Disc space narrowing, as well as disc desiccation, was also noted at each vertebral level. In addition, endplate changes were correlated with age, gender, and BMI (weight(kg)/height(m)2)., Results: A total of 15,000 data points were studied and 422 total changes recorded. A total of 99 vertebral levels were affected in 58 patients. Of these, 171 were of type I, 242 were of type II, and 9 were of type III. L4-L5 and L5-S1 vertebral levels were most commonly involved, having (142, 4.73%) and (116, 3.87%) changes respectively (P<0.0001). The upper and lower aspects of the endplate were affected similarly. Changes most frequently occurred at the anterior aspect of the endplate (P<0.0001). Endplate marrow changes were associated with increasing age (P<0.0001) and, surprisingly, male gender (P<0.0001). Endplate changes were not associated with BMI., Conclusion: The fatty pattern was most common, with the sclerotic pattern being rare. Endplate marrow changes most often occurred at the anterior aspect of the endplate, particularly at L4--L5 and L5--S1 levels. Modic changes occur more frequently with aging, evidence of their degenerative etiology. They were, however, not related to body habitus, but to weight and male gender.

Objective: To determine the range of the patellar tendon length to patellar length ratio on magnetic resonance imaging (MRI) of the knee in order to aid in the establishment of MRI criteria for patella alta and baja., Patients: Two hundred and forty-five patients ages 6-85 (mean 44) years who went through 262 consecutive 1.5 MRI studies of the knee performed during November 2000 through February 2001 were evaluated, regardless of their clinical symptoms., Design: Patellar length (PL) and patellar tendon length (TL) were measured by a single musculoskeletal radiologist on sagittal images by a line connecting the superior and inferior patellar poles and the shortest length of the inner margin of the tendon respectively. TL/PL ratio was subsequently calculated. The distribution of ratios was evaluated; the extreme 2.5% at each end of the distribution was defined as patella alta and baja., Results: The TL/PL ratio ranged between 0.56 and 1.71 (mean 1.05). After plotting the ratios, we noted an asymmetric curve skewed to the left. Based upon calculation of the extreme 2.5% of the ratio at each end of the plot, we determined that the MRI definition of patella alta and baja is a ratio of TL/PL of more than 1.50 and less than 0.74 respectively. We found that females had significantly higher TL/PL ratio than males (1.0878 and 1.0032 respectively). Ratios defined for patella alta and baja were 1.52 and 0.79 respectively in females and 1.32 and 0.74 respectively in males ( p<0.0001)., Conclusion: Patella alta and baja are determined as TL/PL of more than 1.50 and less than 0.74 respectively, somewhat different than traditionally quoted radiographic and previously described MRI criteria.

Objective: To examine the relative change in utilization of magnetic resonance (MR) imaging of the extremities versus diagnostic and therapeutic arthroscopy., Design and Patients: Using the 1993, 1996, and 1999 nationwide Medicare Part B databases, utilization rates (per 100000) were determined for upper and lower extremity MR imaging, diagnostic arthroscopy and therapeutic arthroscopy using CPT-4 codes. Utilization of extremity MR imaging was compared with that of diagnostic and therapeutic arthroscopy in 10 geographic regions of the United States and tracked over time., Results: Combined lower and upper extremity MR imaging utilization per 100000 increased from 393 to 1056 in 1999 (+168.7%). Utilization of diagnostic arthroscopy of the extremities decreased from 18 in 1993 to 8 in 1999 (-55.6%); therapeutic arthroscopy rates increased from 461 in 1993 to 636 in 1999 (+40.0%). Specifically, from 1993 to 1999, utilization of lower extremity MR imaging increased from 270 to 661 (+144.8%). Utilization of diagnostic arthroscopy of the knee over the same time period decreased from 11 to 5 (-54.5%); therapeutic arthroscopy increased from 394 to 501 (+27.2%). Similarly, utilization rates for upper extremity MR imaging increased from 123 to 395 (+221.1%). Utilization of diagnostic arthroscopy of the shoulder over the same time period decreased from 7 to 2 (-71.4%); therapeutic arthroscopy increased from 44 to 104 (+136.4%). No specific geographic trends were ascertained., Conclusion: The utilization of MR imaging of the extremities has markedly increased from 1993 to 1999. During the same time period the utilization of diagnostic arthroscopy has decreased and that of therapeutic arthroscopy has increased. These findings support the hypothesis that there is increased reliance of clinical practitioners on the diagnostic information provided by MR imaging in preoperative clinical decision-making.

Objective: Clinically, females receive anterior cruciate ligament (ACL) tears more commonly than males. We explored whether gender differences exist in MR imaging patterns of ACL tears., Design and Patients: At 1.5 T, two observers evaluated MR examinations of 84 consecutive age-matched patients (42 males, 42 females, aged 16-39) with ACL tears, for mechanism of injury, extent and type of tear, the presence of secondary signs and associated osseous, meniscal and ligamentous injuries., Results: The most common mechanism of injury for both females and males was the pivot shift mechanism (67 and 60%, respectively). Females were more commonly imaged in the acute stage of tear than males (98 and 67%, respectively, p=0.001) and more commonly possessed the typical posterolateral tibial bone contusion pattern (88 and 62%, respectively, p=0.0131). Males exhibited a deeper femoral notch sign (2.7 and 2.0 mm, p=0.007) and medial meniscal, lateral collateral ligament and posterior cruciate ligament injuries more commonly than females (48 and 24%, p=0.009, 30 and 7%, p=0.035, 17 and 0%, p=0.035). There was no significant difference between genders for the presence of other secondary signs and contusion patterns, associated lateral meniscal tears, presence of O'Donoghue's triad or associated medial collateral ligament injuries., Conclusion: Gender differences in MR imaging patterns of ACL tears exist: females are more commonly imaged in the acute stage and more commonly possess posterolateral tibial bone contusions; males have a more severe presentation than females, associated with more severe lateral femoral condyle and soft tissue injuries.

Purpose: To determine the diagnostic performance of functional magnetic resonance cholangiography (fMRC) for the evaluation of anatomic and functional biliary disorders., Materials and Methods: At 1.5 T, 39 MR examinations with conventional MRC and mangafodipir trisodium-enhanced fMRC were retrospectively reviewed by three observers who recorded anatomic (duct dilation, stricture, filling defects) and functional (cholecystitis, obstruction) abnormalities in three modes: MRC alone, fMRC alone, and MRC and fMRC images together (combined-MRC). Performance was determined by comparing findings with each mode to findings of invasive cholangiography (IC) and surgery., Results: Among 75 biliary segments (correlated with IC), the sensitivity/specificity for diagnosing dilation (N = 41) with MRC was 95%/97%; with fMRC, 90%/100%; with combined-MRC, 100%/97%. For stricture (N = 7), the sensitivity/specificity of MRC was 86%/98%; of fMRC, 43%/100%; of combined-MRC, 86%/100%. For filling defects (N = 9), the sensitivity/specificity of MRC was 91%/98%; of fMRC, 82%/100%; of combined-MRC, 91%/100%. For diagnosing obstruction (N = 9), the sensitivity/specificity of MRC, fMRC, and combined-MRC were 89%/100%, 100%/100%, and 100%/100%, respectively. For surgically proven cholecystitis (N = 13), positive predictive values for diagnosing acute/chronic cholecystitis for MRC were 33%/40%; for fMRC, 100%/50%; for combined-MRC, 100%/50%., Conclusion: Although single-shot fast spin echo (SSFSE)-MRC is valuable, the addition of fMRC increased diagnostic performance for functional biliary disorders., (Copyright 2003 Wiley-Liss, Inc.)

Objective: Our purpose was to determine the association between posterior lumbar spine subcutaneous edema, fluid collections, and body weight on lumbar spine MR imaging., Materials and Methods: MR images of the lumbar spine obtained at 1.5 T of 307 consecutive outpatients (191 female, 116 male) were reviewed on the basis of MR imaging signal characteristics for the presence, degree, size, and location of presumed subcutaneous posterior soft-tissue edema and fluid collections. The patients were divided into three weight groups (<70, 70-85, or > 85 kg) and two age groups (<50 or >/=50 years old). Edema was graded on a scale of 0-5 according to its length relative to the vertebral bodies. When present, the fluid collection volumes were calculated. The vertical epicenter of the signal abnormality was noted by vertebral body level., Results: Lumbar soft-tissue edema was seen in 121 patients (39%), and discrete fluid collections were seen in 53 patients (17%). Both degree of edema and volume of fluid collection were associated with increasing weight (p < 0.001 and p = 0.002, respectively) and increasing age (p < 0.001 and p = 0.01, respectively). The degree of edema in females was significantly greater than in males (p = 0.003). However, the sex of the patient did not correlate with frequency of fluid collections (p = 0.12) or volume of collections (p = 0.08). The mean epicenters of edema in females and males were at similar levels (L3.4 and L3.9, respectively, p = 0.54)., Conclusion: The severity of posterior lumbar subcutaneous edema and the volume of fluid collections on MR imaging are associated with increased weight.

Objective: To study the MR appearance of lymph nodes in relation to activity of chronic active hepatitis C, we correlated the findings on MR imaging with a histologic grading of the activity level., Materials and Methods: Fifty patients with chronic active hepatitis C, who had MR imaging examinations and a related histology report from a liver biopsy obtained within 1 month of the MR imaging were chosen from our radiology database and studied retrospectively. All patients were examined over a 4-year period at a single institution to detect cirrhosis or hepatocellular carcinoma. We divided the 50 patients into the mild, moderate, or severe activity groups, according to their histology reports. Two radiologists, unaware of the histologic classifications, individually reviewed the MR images to observe the perihepatic locations, number, size (defined as the sum of the length-by-width products of the largest three nodes), and intensity of the lymph nodes relative to the spleen. The clinical records of the patients were reviewed to check the results of their liver function tests. The lymph node findings on MR imaging were compared with the histologically confirmed activity level of chronic hepatitis C., Results: Forty-four (88.0%) of 50 patients had perihepatic lymph nodes larger than 5 mm on MR images, including 64.2% (9/14) of the patients with mild activity, 96.3% (26/27) of the patients with moderate activity, and 100% (9/9) of the patients with severe activity (p = 0.0034). The average number +/- the standard deviation (SD) of perihepatic lymph nodes was 2.5 +/- 1.8 in patients with mild activity, 5.6 +/- 2.2 in patients with moderate activity, and 8.3 +/- 3.5 in patients with severe activity (p = 0.0001). The average size (+/- SD) of the lymph nodes was 151.0 +/- 104.9 mm(2) in the mild activity group, 366.8 +/- 143.0 mm(2) in the moderate activity group, and 488.2 +/- 244.8 mm(2) in the severe activity group (p = 0.0001). On fat-saturated fast spin-echo T2-weighted MR images, the average number (+/- SD) of hyperintense nodes was 0.17 +/- 0.25 in the mild activity group, 1.7 +/- 0.80 in the moderate activity group, and 2.4 +/- 0.60 nodes in the severe activity group (p = 0.0001). No relationship between histologic activity and results from liver function tests was found., Conclusion: MR imaging depicts perihepatic lymph nodes in most patients with chronic hepatitis C. Lymph node number, size, and hyperintensity were related to the activity of chronic hepatitis C, but the results of liver function tests were not.

Objective: We examined Medicare and fee-for-service data sets to understand better the utilization of MR imaging for imaging the pelvis, abdomen, and chest relative to its use in imaging for other body parts and to the utilization of CT., Materials and Methods: CT and MR imaging procedure volumes for pelvis, abdomen, chest, and total were extracted from the 1993, 1996, and 1999 Health Care Financing Administration Physician/Supplier Procedure Summary Master Files, based on CPT-4 codes. We also analyzed a fee-for-service health insurance database for January 1998 through July 1999 from a single northeastern state, which included provider location (rural, suburban, or urban) and type (teaching or nonteaching site)., Results: The greatest 3-year Medicare increase was for abdominal MR imaging, from 1996 to 1999 (101% increase). However, pelvic, abdominal, and chest MR imaging together remained less than 5% of total MR imaging. Abdominal MR imaging increased more than did total MR imaging in all 10 Health Care Financing Administration regions. In the fee-for-service database, the relative procedure volume of abdominal MR imaging varied approximately fivefold from rural to urban provider locations, and approximately double from nonteaching to teaching hospitals., Conclusion: Although far more abdominal CT than abdominal MR imaging is performed, the rate of abdominal MR imaging utilization has increased more rapidly since 1993. The relative procedure volume of abdominal MR imaging varied more than fivefold from rural to urban provider locations and double from nonteaching to teaching hospitals.

Purpose: To evaluate single-shot fast spin-echo (SE) magnetic resonance (MR) imaging for depiction of pancreatic cysts in a large number of patients and to analyze cyst prevalence with respect to patient age and sex and other clinical information., Materials and Methods: Single-shot fast SE images of the pancreas were obtained in 1,444 patients. The images were reviewed for presence of pancreatic cysts, which were classified as simple and nonsimple types, and cyst diameters were measured. kappa statistic, Fisher exact, McNemar Q, and Pearson product moment correlation tests were performed., Results: Two hundred eighty-three (19.6%) patients had at least one pancreatic cyst. The prevalence of pancreatic cysts increased with age (r = 0.96). The percentages of male and female patients with pancreatic cysts (20.4% vs 18.8%) were not significantly different. Two hundred seventy-one (18.8%) patients had simple cysts, and 147 (10.2%) had nonsimple cysts. Of 283 patients with pancreatic cysts, 158 (55.8%) had only one pancreatic cyst. The number of patients with multiple cysts increased with age after 70 years. Four hundred fifteen (83.8%) cysts were 10 mm in diameter or smaller; 56 (11.3%), 11-20 mm in diameter; and 24 (4.9%), 21 mm in diameter or larger. Sixteen (5.7%) patients with pancreatic cysts had malignant pancreatic tumors, and 75 (26.5%) patients had pancreatitis., Conclusion: The prevalence of pancreatic cysts at single-shot fast SE MR imaging-especially cysts with a diameter smaller than 10 mm-is similar to that of pancreatic cysts at autopsy and higher than that of pancreatic cysts at transabdominal ultrasonography. Prevalence is especially high in patients with pancreatitis., (Copyright RSNA, 2002)

Purpose: To determine the trends in utilization of non-neurologic (ie, body) magnetic resonance (MR) imaging and of MR angiographic examinations performed from 1993 to 1998, the trends in non-radiologist participation in MR imaging, and the relative reimbursements for these examinations compared with those for all other noninvasive imaging studies performed in 1998., Materials and Methods: By using the 1993, 1996, and 1998 nationwide Medicare Part B databases, utilization rates per 100,000 Medicare beneficiaries and physician reimbursements were determined for seven MR angiography and 14 body MR imaging CPT-4 (Current Procedural Terminology, version 4) codes. Medicare specialty codes were used to categorize physicians as radiologists or non-radiologists., Results: The utilization rate per 100,000 Medicare beneficiaries for all 21 MR angiography and body MR imaging codes increased from 649 in 1993 to 1,253 in 1996 and to 1,876 in 1998--a 189% increase. These rates represented 0.55% of the total noninvasive imaging volume in 1998 and 2.8% of physician reimbursements. Musculoskeletal MR imaging utilization increased 142% from 1993 to 1998 compared with a 58% increase in the utilization of other body MR imaging studies. Non-radiologist participation in musculoskeletal MR imaging increased from 2.9% in 1993 to 3.6% in 1996 and to 5.6% in 1998., Conclusion: MR angiography and body MR imaging utilization rates increased substantially from 1993 to 1998. However, these studies still account for a minor fraction of all noninvasive imaging examinations performed and fees reimbursed. MR angiography and musculoskeletal MR imaging utilization has increased rapidly. Non-radiologist participation in musculoskeletal MR imaging is increasing.

Imaging is an important cost driver in health care, and its use grew rapidly in the early 2000s. Several studies toward the end of the decade suggested that a leveling off was beginning to occur. In this study we examined more recent data to determine whether the slowdown had continued. Our data sources were the nationwide Medicare Part B databases for the period 2001-14. We calculated utilization rates per 1,000 enrollees for all advanced imaging modalities. We also calculated professional component relative value unit (RVU) rates per 1,000 beneficiaries for all imaging modalities, as RVU values provide a measure of complexity of imaging services and may in some ways be a better reflection of the amount of work involved in imaging. We found that utilization rates and RVU rates grew substantially until 2008 and 2009, respectively, and then began to drop. The downward trend in both rates persisted through 2014. Federal policies appear to have achieved the desired effect of ending the rapid growth of imaging that had been seen in earlier years. [ABSTRACT FROM AUTHOR]

A decade of rapidly rising outpatient advanced imaging utilization ended toward the end of the past decade, with slow growth since. This has been attributed to repetitive reimbursement cuts, medical radiation exposure concerns, increasing deductibles and patient copayments, and the influence of radiology benefit management companies. State Medicaid programs have been reluctant to institute radiology benefit management preauthorization programs since the time burden for obtaining test approval could cause providers to drop out. Also, these patients may lack the knowledge to appeal denials, and medically necessary tests could be denied with adverse outcomes. Little data exist demonstrating the efficacy of such programs in decreasing utilization and cost. We report a 2-year experience with an outpatient advanced imaging prior notification program for a large state Medicaid fee-for-service population. The program did not allow any denials, but nevertheless the data reveal a large, durable decrease in advanced imaging utilization and cost. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to evaluate whether affected bowel in Crohn's disease patients can be identified by observing decreased peristalsis (frozen bowel sign) using cine balanced steady-state free precession (cine BSSFP) images. Materials and methods: 5 radiologists independently reviewed cine BSSFP sequences from randomized MR Enterography (MRE) exams for 30 normal and 30 Crohn's disease patients, graded overall small bowel peristalsis from slowest to fastest, and graded peristalsis for the most abnormal small bowel segment. Sensitivity and specificity of the frozen bowel sign for diagnosing Crohn's disease were calculated. T tests of the peristalsis difference between abnormal segments and overall small bowel were conducted. Results: For 5 readers, the sensitivity and specificity of cine BSSFP of the frozen bowel sign for diagnosing Crohn's disease ranged from 70% to 100% and 87% to 100%, respectively. There were significant differences in peristalsis between abnormal small bowel segments and the overall small bowel for Crohn's patients, but not in the overall small bowel between normal-MRE patients and Crohn's disease patients. Conclusion: Abnormal Crohn's small bowel segments have significantly decreased peristalsis compared to normal small bowel, which can be identified using cine BSSFP sequences as the frozen bowel sign. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to evaluate whether affected bowel in Crohn's disease patients can be identified by observing decreased peristalsis (frozen bowel sign) using cine balanced steady-state free precession (cine BSSFP) images. Materials and methods: 5 radiologists independently reviewed cine BSSFP sequences from randomized MR Enterography (MRE) exams for 30 normal and 30 Crohn's disease patients, graded overall small bowel peristalsis from slowest to fastest, and graded peristalsis for the most abnormal small bowel segment. Sensitivity and specificity of the frozen bowel sign for diagnosing Crohn's disease were calculated. T tests of the peristalsis difference between abnormal segments and overall small bowel were conducted. Results: For 5 readers, the sensitivity and specificity of cine BSSFP of the frozen bowel sign for diagnosing Crohn's disease ranged from 70% to 100% and 87% to 100%, respectively. There were significant differences in peristalsis between abnormal small bowel segments and the overall small bowel for Crohn's patients, but not in the overall small bowel between normal-MRE patients and Crohn's disease patients. Conclusion: Abnormal Crohn's small bowel segments have significantly decreased peristalsis compared to normal small bowel, which can be identified using cine BSSFP sequences as the frozen bowel sign. [ABSTRACT FROM AUTHOR]

Presence of a dorsal sector of liver that completely encircles the IVC may increase difficulty of IVC preservation for orthotopic liver transplantation (OLT). We sought to evaluate the incidence of IVC encirclement by hepatic parenchyma using preoperative MRI and CT and its effect on surgical technique and complications. CT or MRI examinations less than 12 months before OLT were reviewed independently and blindly by two radiologists in 95 patients, with patient consent waived by IRB. IVC preservation was attempted for all patients without regard to imaging findings. Surgical records were reviewed regarding choice of technique or operative difficulties, and their relationship to complete IVC encirclement was calculated using ROC analysis and Fischer exact test. Complete encirclement was found by both readers in 16 of 95 patients (17%). Resection of the recipient IVC was required in three of 95 patients, two of whom had complete IVC encirclement. Association of complete IVC encirclement with surgical IVC resection had an area under the ROC curve of 0.752. Routine pretransplant assessment of IVC encirclement by dorsal sector hepatic tissue using MRI and CT may help identifying patients in whom IVC preservation will be difficult. [ABSTRACT FROM AUTHOR]

The utilization rate of advanced diagnostic imaging (magnetic resonance imaging, computed tomography, and nuclear medicine) in Medicare outpatients rose 72.7 percent between 2000 and 2005, sparking concern among policymakers. However, analysis of discretionary use of these exams indicates that their use largely stabilized after 2005. Some have credited the Deficit Reduction Act of 2005, which sharply reduced reimbursements for advanced imaging done in physicians' offices. But the fact that the leveling was more pronounced in hospital outpatient facilities than in physicians' offices indicates that the explanation lies elsewhere. More likely, there has been a change in physicians' ordering patterns, possibly due to the influence of radiology business management companies (RBM5) and imaging guidelines promulgated by specialty societies. [ABSTRACT FROM AUTHOR]