Hospital outpatient prospective payment under Medicare: understanding the system and its implications

The newly implemented Medicare hospital outpatient prospective payment system provides fixed prospectively determined reimbursement for technical and other nonphysician services provided to beneficiaries in the hospital outpatient setting. As such, it represents the latest attempt by the federal government to control health care costs through prospective bundled payment systems such as the well-known Medicare diagnosis-related group system for hospital inpatients. The new system is complex, however, with several discrete reimbursement mechanisms possible for the same service. This complexity, in concert with the major change in outpatient reimbursement that the system represents, creates considerable uncertainty for radiologists and for medicine in general. It is incumbent on the radiology community to understand and assess the hospital outpatient prospective payment system and to work with the Centers for Medicare and Medicaid Services to minimize any potential negative effects on the profession and on patients.     

Trends in the utilization of MR angiography and body MR imaging in the US Medicare population: 1993-1998

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.     

Determinants of acquisition of MR imaging units in an era of prospective payment

A survey was undertaken to examine the impact of Medicare's Prospective Payment System (PPS) and other recent changes in the health care environment on providers' decisions regarding acquisition of high-cost technologic equipment. The survey group included 199 hospitals and freestanding imaging centers known to have acquired magnetic resonance (MR) imaging units, as well as a random sample of 400 hospitals whose acquisition decisions were unknown to the authors. Fifty-eight percent of the known adopters and 61% of the randomly selected hospitals responded to the survey. Nonadopters' decisions were dominated by economic considerations, including the high cost of MR imagers and concerns about Medicare's reimbursement policies. Competition and a desire to provide the highest quality of care are counterbalancing the retardant effects of PPS, however, and are stimulating widespread diffusion of MR imagers.     

MR imaging and CT in three cases of Sturge-Weber syndrome: prospective comparison

Three patients with Sturge-Weber syndrome (5 months, 6 years, and 17 years old) were studied prospectively with MR imaging and CT of the brain. Both techniques demonstrated parenchymal volume loss, choroid plexus enlargement, calvarial hemiatrophy, and proptosis. In regions of parenchymal volume loss, MR alone demonstrated thickened cortex with decreased convolutions and abnormal white matter. A focal thalamic lesion and prominent medullary and subependymal veins were also shown better by MR. However, CT definitively demonstrated the characteristic cortical calcification, while T2-weighted MR images detected only smaller, nonspecific foci of hypointense signal. MR and CT are complementary in the evaluation of Sturge-Weber syndrome.     

双嘧达莫心脏MR成像评价预后意义:一个多中心性前瞻性注册表

目的评价双嘧达莫心脏MR成像对来自一个大型多中心缺血性胸痛登记表中病人发生重大事件的预测意义。材料与方法经机构伦理委员会批准,并书面告知病人获得同意,总共有1722例因胸痛接受心脏MR成像的病人包括在内,采用17段模式分析了静息状态下的壁运动异常(WMA)、充血灌注缺陷(PD)、晚期钆增强(LGE)和诱导壁运动异常     

High-volume providers and brachytherapy practice: A Medicare provider utilization and payment analysis

PurposeBrachytherapy is an important component of the treatment of gynecologic and prostate cancers, with data supporting its impact on clinical outcomes. Prior data have suggested that brachytherapy tends to be focused at high-volume centers. Medicare reimbursement data can provide an understanding of the distribution of brachytherapy cases among billing providers. The objective of this study is to quantify the distribution of brachytherapy cases and high volume providers.Methods and MaterialsThe Medicare Physician and Other Supplier Public Use File was queried for individual physicians who had performed brachytherapy for more than 10 patients with gynecologic or prostate cancer in the years 2012–2015. Aggregate data were also queried. Trends were identified, and basic summary statistics were tabulated.ResultsDuring the study period, there was an increase in vaginal brachytherapy (3328 unique cases in 2012–4308 in 2015) but a decrease in intrauterine implants, such as tandem placements (1522 in 2012–1307 in 2015) and prostate brachytherapy (8860 in 2012–6527 in 2015). High-volume providers treating more than 10 patients represented a disproportionate number of patients treated, particularly with intra-uterine brachytherapy, representing no more than 1.2% of the active providers in a given year but up to 11.1% of intra-uterine brachytherapy cases.ConclusionsAmong Medicare claims, a small number of providers accounted for a significant proportion of gynecologic and prostate brachytherapy cases, particularly in the case of intrauterine implants. The vast majority of brachytherapy providers perform limited cases in this population. Efforts toward improving access to intrauterine implants in Medicare patients should be a national priority.     

Hepatocellular carcinoma in cirrhotic patients: prospective comparison of US, CT and MR imaging

Objectives

To prospectively compare the diagnostic performance of ultrasound (US), multidetector computed tomography (MDCT) and contrast-enhanced magnetic resonance imaging (MRI) in cirrhotic patients who were candidates for liver transplantation.

Methods

One hundred and forty consecutive patients with 163 hepatocellular carcinoma (HCC) nodules underwent US, MRI and MDCT. Diagnosis of HCC was based on pathological findings or substantial growth at 12-month follow-up. Four different image datasets were evaluated: US, MDCT, MRI unenhanced and dynamic phases, MRI unenhanced dynamic and hepatobiliary phase. Diagnostic accuracy, sensitivity, specificity, PPV and NPV, with corresponding 95 % confidence intervals, were determined. Statistical analysis was performed for all lesions and for three lesion subgroups (<1 cm, 1-2 cm, >2 cm).

Results

Significantly higher diagnostic accuracy, sensitivity and NPV was achieved on dynamic + hepatobiliary phase MRI compared with US, MDCT and dynamic phase MRI alone. The specificity and PPV of US was significantly lower than that of MDCT, dynamic phase MRI and dynamic + hepatobiliary phase MRI. Similar results were obtained for all sub-group analyses, with particular benefit for the diagnosis of smaller lesions between 1 and 2 cm.

Conclusions

Dynamic + hepatobiliary phase MRI improved detection and characterisation of HCC in cirrhotic patients. The greatest benefit is for diagnosing lesions between 1 and 2 cm.

Key Points

? US, CT and MRI can all identify HCC in cirrhotic patients ? US has good sensitivity but suffers from false-positive findings ? Dynamic CT and MR have similar diagnostic performance for diagnosing HCC ? Dynamic + hepatobiliary phase MRI significantly improves detection and characterisation of HCC ? The greatest benefit is for the diagnosis of lesions between 1 and 2 cm     

Primary lung cancer staging: prospective comparative study of MR imaging with CT

Forty-four patients with bronchogenic carcinoma were studied prospectively by both computed tomography (CT) and magnetic resonance (MR) imaging of the thorax during the week preceding thoracotomy. Transaxial MR imaging sequences included T1- and T2-weighted sequences. Coronal and sagittal T1-weighted sequences were added according to tumor location. CT and MR studies were reviewed separately, and the results were compared with surgical and pathologic findings on the basis of TNM classification. No statistically significant differences were found between the two imaging methods for the evaluation of tumor extent or node involvement. T2-weighted sequences did not yield further information on tumor extent or node involvement. Additional imaging planes (coronal or sagittal) appeared useful to study chest wall invasion. Analysis of concordances and discordances did not indicate whether one modality could be substituted for the other, or which diagnostic strategy might be more useful.     

Central nervous system disease in acquired immunodeficiency syndrome: prospective correlation using CT, MR imaging, and pathologic studies

A prospective study compared the abilities of high-resolution computed tomography (HRCT) and magnetic resonance (MR) imaging in detection and evaluation of central nervous system disease in neurologically symptomatic patients with acquired immunodeficiency syndrome (AIDS). Eighteen CT scans and 19 MR images in 14 patients were compared. HRCT images with contrast material enhancement were superior to unenhanced 0.35-T MR images for differentiating a lesion from surrounding edema, discriminating between lesions in close proximity, locating lesions for biopsy, judging lesion activity, detecting small cortical lesions with minimal edema, and spatial resolution. MR imaging was superior to CT scanning in evaluation of white-matter lesions and detection of small lesions surrounded by edema. MR imaging exhibited higher contrast resolution and greater sensitivity. Complementary uses of MR and CT imaging are suggested.     

Cirrhosis: CT and MR imaging evaluation

In this article, we present the CT and MR imaging characteristics of the cirrhotic liver. We describe the altered liver morphology in different forms of viral, alcoholic and autoimmune end-stage liver disease. We present the spectrum of imaging findings in portal hypertension, such as splenomegaly, ascites and varices. We describe the patchy and lacelike patterns of fibrosis, along with the focal confluent form. The process of hepatocarcinogenesis is detailed, from regenerative to dysplastic nodules to overt hepatocellular carcinoma. Different types of non-neoplastic focal liver lesions occurring in the cirrhotic liver are discussed, including arterially enhancing nodules, hemangiomas and peribiliary cysts. We show different conditions causing liver morphology changes that can mimic cirrhosis, such as congenital hepatic fibrosis, "pseudo-cirrhosis" due to breast metastases treated with chemotherapy, Budd-Chiari syndrome, sarcoidosis and cavernous transformation of the portal vein.     

Soft-tissue masses of the locomotor system: comparison of MR imaging with CT

Magnetic resonance (MR) images and computed tomographic (CT) scans of histologically characterized soft-tissue masses of the locomotor system in 35 patients were compared for image contrast, demonstration of bone destruction, and display of extent and anatomic relationships of the masses. Subjective criteria for predicting malignancy were tested. T1 measurements were made in a few cases. Intensities of masses relative to those of fat and muscle in spin-echo T1-weighted and highly T2-weighted images were evaluated for correlation with tissue type. Subjective value of using coronal and sagittal images was assessed. Because of its superior inherent image contrast and its ability to provide direct sagittal and coronal images, MR was better than CT in demonstrating size and extent of most tumors and their relationships to vascular and nonvascular structures. However, bone destruction was more difficult to see with MR. Except for fatty tumors, MR was not helpful in identifying tissue type. Subjective criteria were of limited value in distinguishing benign from malignant lesions. Moreover, there is currently no credible evidence that T1 or T2 measurements are helpful in this regard. Study results suggest that MR is superior to CT in evaluating soft-tissue masses of the locomotor system. If an MR examination is performed, CT may not be necessary in certain cases unless bone involvement is suspected.     

Cervical MR imaging in postural headache: MR signs and pathophysiological implications

BACKGROUND AND PURPOSE: Postural headache most often occurs after lumbar puncture as post-lumbar puncture headache (PLPH) or, rarely, spontaneously as spontaneous intracranial hypotension headache (SIHH). In this prospective study, we used spinal MR imaging to determine the findings that would assist in the diagnosis of PLPH and SIHH and that would further our pathophysiological understanding of postural headache. METHODS: The study group consisted of 15 healthy volunteers and 20 patients with postural headache: nine with SIHH and 11 with PLPH. The craniocervical junction and the cervical spine were studied using T2-weighted fast spin-echo and T1-weighted spin-echo sequences in the axial and sagittal planes. Follow-up studies were performed in 13 patients. RESULTS: Dilatation of the anterior internal vertebral venous plexus was the most constant finding, present in 17 (85%) of 20 patients with postural headache. Spinal hygromas, whose location as subdural or epidural could not be exactly determined, were present in 14 patients (70%). A focal fluid collection was detected in the retrospinal region at the C1-C2 level in six patients with SIHH and in four patients with PLPH (50%). Tonsillar descent was detected in only one patient, and subtentorial hygroma in five patients. No abnormalities were found in the volunteers. CONCLUSION: The MR signs of dilatation of the venous plexus, presence of spinal hygromas, and presence of retrospinal fluid collections can help to establish the diagnosis of intracranial hypotension. They are probably the result of decreased CSF volume, with the retrospinal fluid collections being a transudate from the venous plexus rather than frank extravasation. Resolution of these signs parallels resolution of the headache.     

Craniopharyngioma: CT and MR imaging in nine cases

Magnetic resonance (MR) imaging and CT examinations were performed in nine patients with surgically proven craniopharyngioma. Computed tomography was found to be superior to MR in detection of calcification and cyst formation. Extent of involvement of adjacent structures (e.g., optic chiasm, third ventricle, and intracavernous carotid artery) was more clearly delineated by MR. Craniopharyngioma fluid collections were found to be uniformly bright on T2-weighted sequences. However, on T1-weighted sequences, the signal intensity of the fluid ranged from hypointense to hyperintense, reflecting the heterogeneous contents of cysts in these tumors. Since calcification and cyst formation are hallmarks of craniopharyngiomas, we believe that CT is more specific than MR in diagnosis of craniopharyngiomas. Magnetic resonance, however, offers a more accurate assessment of the tumor extent.     

Kimura disease: CT and MR imaging findings

BACKGROUND AND PURPOSE:KD is a rare chronic inflammatory disorder of unknown etiology. The purpose of this study was to evaluate the CT and MR imaging findings of KD in the head and neck.MATERIALS AND METHODS:We retrospectively reviewed the CT (n = 21) and MR (n = 9) images obtained in 28 patients (24 males and 4 females; mean age, 32 years; age range, 10–62 years) with histologically proved KD in the head and neck.RESULTS:In these 28 patients, CT and MR images demonstrated a total of 52 non-nodal lesions, 1–8 cm in greatest diameter, in the head and neck. The lesions were unilateral in 11 patients and bilateral in 17 patients. Eleven patients had a solitary lesion, and 17 patients had 2–4 lesions. The parotid and/or periparotid area was the most frequent location, with 36 lesions in 23 patients. The margin of the lesions was well-defined in 1 and ill-defined in 51 cases. Compared with the adjacent muscle, the MR signal intensity of all lesions was iso- to slightly hyperintense on T1-weighted images and hyperintense on T2-weighted images. Most of the lesions demonstrated mild or moderate enhancement on postcontrast CT scans and moderate or marked enhancement on postcontrast MR images. MR images also showed tubular signal-intensity voids in 7 of 13 lesions. Associated lymphadenopathy was demonstrated in 23 patients, usually bilaterally.CONCLUSIONS:Multiple ill-defined enhancing masses within and around the parotid gland with associated regional lymphadenopathy are characteristic CT and MR imaging findings of KD in the head and neck.

KD is a rare chronic inflammatory disorder of unknown etiology, characterized by angiolymphoid proliferation with peripheral eosinophilia and elevated serum IgE. The disease has a predilection for the head and neck and typically occurs in young Asian males.^1,2 Although it was first described in the Chinese literature in 1937 under the designation of “eosinophilic hyperplastic lymphogranuloma,” it was not until 1948 that the disease to become widely known as KD when Kimura and Ishikawa³ reported it in the Japanese literature.⁴ KD often produces subcutaneous tumorlike nodules with frequently associated involvement of the major salivary gland and regional lymph nodes.⁵Although the clinical and histopathologic findings of KD have been well described in the literature, only a few reports have dealt with its radiologic findings, and generally as case reports or small case series.^6–15 The purpose of this study was to describe the CT and MR imaging findings of histologically proved KD involving the head and neck in 28 patients. To our knowledge, this is the largest imaging study of patients with KD of the head and neck.