Radiology order decision support: examination-indication appropriateness assessed using 2 electronic systems.

PURPOSE: The goal of the study was to determine the effects of guideline implementation strategy using 2 commercial radiology clinical decision support (CDS) systems. METHODS: The appropriateness and insurance dispositions of MRI and CT orders were evaluated using the Medicalis SmartReq and Nuance RadPort CDS systems during 2 different 3-month periods. Logistic regression was used to compare these outcomes between the 2 systems, after adjusting for patient-mix differences. RESULTS: Approximately 2,000 consecutive outpatient MRI and CT orders were evaluated over 2 periods of 3 months each. Medicalis scored 60% of exams as "indeterminate" (insufficient information) or "not validated" (no guidelines). Excluding these cases, Nuance scored significantly more exams as appropriate than did Medicalis (80% versus 51%, P < .001) and predicted insurance outcome significantly more often (76% versus 58%, P < .001). Only when the Medicalis "indeterminate" and "not validated" categories were combined with the high- or moderate-utility categories did the 2 CDS systems have similar performance. Overall, 19% of examinations with low-utility ratings were reimbursed. Conversely, 0.8% of examinations with high- or moderate-utility ratings were denied reimbursement. CONCLUSIONS: The chief difference between the 2 CDS systems, and the strongest influence on outcomes, was how exams without relevant guidelines or with insufficient information were handled. Nuance augmented published guidelines with clinical best practice; Medicalis requested additional information utilizing pop-up windows. Thus, guideline implementation choices contributed to decision making and outcomes. User interface, specifically, the number of screens and completeness of indication choices, controlled CDS interactions and, coupled with guidance implementation, influenced willingness to use the CDS system.

Third head of the gastrocnemius: an MR imaging study based on 1,039 consecutive knee examinations.

OBJECTIVE: The objectives of this study were to determine the frequency of a third head of the gastrocnemius and to describe the course, morphology, and insertion of the third head as seen on the basis of routine magnetic resonance (MR) imaging of the knee. MATERIALS AND METHODS: This study was a prospective study of 1,039 consecutive knee MR examinations which were performed for symptoms of pain not associated with claudication. The examinations were performed between September 2004 and January 2005 and were evaluated for the presence of an anomalous third head of the gastrocnemius and to determine its origin and course. Examinations were performed on a variety of magnets ranging from 0.2 to 1.5 T. RESULTS: Of the 1,039 knees, 20 (1.9%) demonstrated an anomalous third head of the gastrocnemius which was seen arising near the midline of the posterior distal femur, between the mid and medial aspect, and joining the medial aspect of the lateral head of the gastrocnemius. The size of the third head varied from a thin threadlike muscle to a rather bulky muscle. In all of these patients, the third head coursed lateral to the popliteal vessels, and none coursed between the vessels. One additional case of a third head of the gastrocnemius was seen which joined the medial head of the gastrocnemius. CONCLUSION: A third head of the gastrocnemius joining the lateral head is not an uncommon variant, seen in 1.9% of knee MR examinations. Most are not associated with vascular symptoms.

Selective atrophy of the abductor digiti quinti: an MRI study.

OBJECTIVE: Entrapment of the first branch of the lateral plantar nerve is a well-recognized but diagnostically elusive cause of heel pain. The MR finding of selective atrophy of the abductor digiti quinti (ADQ) muscle has been reported as a marker of such entrapment. We performed a prospective study of consecutive patients undergoing foot and ankle MRI to determine the prevalence of ADQ atrophy and to examine the clinical symptoms of patients found to have ADQ atrophy. SUBJECTS AND METHODS: A prospective study of all patients referred for ankle and foot MRI examinations was performed. Six hundred two patients were included in the study: 387 females and 215 males. All images were evaluated for the presence of selective fatty atrophy of the ADQ muscle. The clinical notes on all patients with findings of ADQ atrophy were analyzed for descriptions of symptoms leading to the MR examination, the presence of symptoms that might be related to nerve entrapment, and the influence on clinical management related to the MR finding of ADQ atrophy. RESULTS: Thirty-eight of the 602 patients had selective fatty atrophy of the ADQ, 29 females and nine males. Only one patient had a clinical diagnosis of possible nerve entrapment before MR examination. MRI findings of ADQ atrophy altered clinical management in only one patient. CONCLUSION: Selective fatty atrophy of the ADQ is not a rare finding on MR examination of the foot and ankle, being seen in 6.3% of all studies and in 7.5% of all studies in females. The clinical relevance of selective ADQ atrophy seen on MRI is uncertain.

Acute low back pain and radiculopathy: MR imaging findings and their prognostic role and effect on outcome.

PURPOSE: To prospectively determine in patients with acute low back pain (LBP) or radiculopathy, the magnetic resonance (MR) imaging findings, prognostic role of these findings, and effect of diagnostic information on outcome. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained. This study was HIPAA compliant. A total of 246 patients with acute-onset LBP or radiculopathy were randomized to either the early information arm of the study, with MR results provided within 48 hours, or the second arm of the study, where both patients and physicians were blinded to MR results, unless this information was critical to patient care. Patients underwent 6 weeks of conservative care. Roland function scoring, visual pain analog, Short Form 36 health status survey, self-efficacy scoring, and a fear avoidance questionnaire were completed at presentation; at 2-, 4-, 6-, and 8-week follow-up; and at 6-, 12-, and 24-month follow-up. A second MR imaging examination was performed at 6-week follow-up. Multivariate logistic regression analysis was used to determine which imaging and nonimaging variables can be used to predict improvement in Roland function and patient satisfaction. The chi(2) test and repeated-measures analysis of variance were used to compare outcome of blinded and unblinded patients. RESULTS: Herniation was identified in 60% (n = 147) of patients at the initial examination. The prevalence of herniations in patients with LBP (57%) (n = 85) and those with radiculopathy (65%) (n = 62) were similar (P = .217), although patients with radiculopathy were more likely to have stenosis and nerve root compression (P < .006). There was no relationship between herniation type, size, and behavior over time with outcome. An improvement of 50% or more in Roland function score at 6-week follow-up occurred 2.7 times as often among patients with a herniation at baseline (P = .003). Improvement at 6-week follow-up was similar in unblinded (60%) (n = 55) and blinded (67%) (n = 57) patients (P = .397). Self-efficacy, fear avoidance beliefs, and the Short Form 36 subscales were similar for blinded and unblinded patients. CONCLUSION: In typical patients with LBP or radiculopathy, MR imaging does not appear to have measurable value in terms of planning conservative care. Patient knowledge of imaging findings does not alter outcome and is associated with a lesser sense of well-being.