The impact of ankle radiographs on the diagnosis and management of acute ankle injuries

Anatomical subgroup analysis of the MERIDIAN cohort: posterior fossa abnormalities

OBJECTIVE

To assess the diagnostic and clinical contribution of fetal magnetic resonance imaging (MRI) in fetuses of the MERIDIAN cohort diagnosed with abnormalities of the posterior fossa as the only intracranial abnormality recognized on antenatal ultrasound.

METHODS

This was a subgroup analysis of the MERIDIAN study of fetuses with abnormalities of the posterior fossa (with or without ventriculomegaly) diagnosed on antenatal ultrasound in women who had MRI within 2 weeks of ultrasound and for whom outcome reference data were available. The diagnostic accuracy of ultrasound and MRI is reported, as well as indicators of diagnostic confidence and effects on prognosis and clinical management. Appropriate diagnostic confidence was assessed by the score-based weighted average method, which combines diagnostic accuracy with diagnostic confidence data.

RESULTS

Abnormalities confined to the posterior fossa according to ultrasound were found in 81 fetuses (67 with parenchymal and 14 with cerebrospinal fluid-containing lesions). The overall diagnostic accuracy for detecting an isolated posterior fossa abnormality was 65.4% for ultrasound and 87.7% for MRI (difference, 22.3% (95% CI, 14.0-30.5%); P < 0.0001). There was an improvement in 'appropriate' diagnostic confidence, as assessed by the score-based weighted average method (P < 0.0001), and a three-fold reduction in 'high confidence but incorrect diagnosis' was achieved using MRI. Prognostic information given to the women changed after MRI in 44% of cases, and the overall effect of MRI on clinical management was considered to be 'significant', 'major' or 'decisive' in 35% of cases.

CONCLUSIONS

Our data suggest that any woman whose fetus has a posterior fossa abnormality as the only intracranial finding on ultrasound should have MRI for further evaluation. This is on the basis of improved diagnostic accuracy and confidence, which impacts substantially on the prognostic information given to women as well as their clinical management. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Anatomical subgroup analysis of the MERIDIAN cohort: failed commissuration

OBJECTIVE

To assess the contribution of fetal magnetic resonance imaging (MRI) in fetuses of the MERIDIAN cohort diagnosed with either agenesis or hypogenesis of the corpus callosum (referred to collectively as failed commissuration) on antenatal ultrasound.

METHODS

This was a subgroup analysis of the MERIDIAN study of fetuses with failed commissuration (with or without ventriculomegaly) diagnosed on ultrasound in women who had MRI assessment within 2 weeks of ultrasound and for whom outcome reference data were available. The diagnostic accuracy of ultrasound and MRI was studied, as well as indicators of diagnostic confidence and effects on prognosis/clinical management. Appropriate diagnostic confidence was assessed by the score-based weighted average method, which combines diagnostic accuracy with diagnostic confidence data.

RESULTS

In the MERIDIAN cohort, 79 fetuses were diagnosed with failed commissuration on ultrasound (55 with agenesis and 24 with hypogenesis of the corpus callosum). The diagnostic accuracy for detecting failed commissuration was 34.2% for ultrasound and 94.9% for MRI (difference, 60.7% (95% CI, 47.6-73.9%), P < 0.0001). The diagnostic accuracy for detecting hypogenesis of the corpus callosum as a discrete entity was 8.3% for ultrasound and 87.5% for MRI, and for detecting agenesis of the corpus callosum as a distinct entity was 40.0% for ultrasound and 92.7% for MRI. There was a statistically significant improvement in 'appropriate' diagnostic confidence when using MRI as assessed by the score-based weighted average method (P < 0.0001). Prognostic information given to the women changed in 36/79 (45.6%) cases after MRI and its overall effect on clinical management was 'significant', 'major' or 'decisive' in 35/79 cases (44.3%).

CONCLUSIONS

Our data suggest that any woman whose fetus has failed commissuration as the only intracranial finding detected on ultrasound should have MRI examination for further evaluation. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Diagnostic yield of sonography in infants with suspected hip dysplasia: diagnostic thinking efficiency and therapeutic efficiency

OBJECTIVE

The purpose of this study is to determine the impact of sonographic information on surgeons' diagnostic thinking and decision making in the management of infants with a possible diagnosis of developmental dysplasia of the hip (DDH).

SUBJECTS AND METHODS

Five experienced orthopedic surgeons examined 66 hips of infants who were referred for a possible diagnosis of DDH and reported for each hip a confidence level about the diagnosis of DDH using a visual analog scale (VAS) before and after hip sonography was obtained. In addition, they reported a management plan. We determined the efficiency in diagnostic thinking by calculating the mean gain in diagnostic confidence as the percentage change in VAS scores and the impact of sonography on the management plan (therapeutic efficiency).

RESULTS

Sonography led to a change in diagnosis in 52% (34/66) of hips. The management plan changed in 32% (21/66) of hips. The mean gain in reported diagnostic confidence was 19.4% (95% CI, 17.3-21.5%), but it was 46.0% (95% CI, 30.5-60.8%) in cases where the management changed as a result of sonography (difference, 37.7%; p < 0.0001). The greatest yield of sonography was found in hips showing limited abduction. Sonography obviated further follow-up in 23% (15/66) of cases.

CONCLUSION

Sonography refined the diagnostic thinking of clinicians and led to a change in diagnosis in 52% of cases. Management plans changed in 32% of cases.

Assessing diagnostic confidence: a comparative review of analytical methods

RATIONALE AND OBJECTIVES

The ability of a test to influence diagnostic confidence is used as a measure of its efficacy. Our aim was to compare analytic methods that evaluate changes in confidence.

MATERIALS AND METHODS

The approaches compared were "basic," "retained diagnoses," "Omary," "Tsushima," and "score-based" methods. For illustration, data from a clinical study assessing changes in diagnostic confidence (0%-100%) before and after abdominopelvic computed tomography (CT) in patients with acute abdominal pain were used.

RESULTS

The basic, retained diagnoses and Omary methods all ignore whether the test yields a correct diagnosis (confident, but incorrect, diagnoses are regarded positively). Although the Tsushima method takes some account of diagnostic accuracy, all misdiagnoses are considered equal. The score-based method addresses some of the fundamental limitations in the other analytical methods, such as diagnostic accuracy and the varying nature of different misdiagnoses. In the case study, mean (SD) diagnostic confidence for the cohort as a whole (n = 62) increased following CT: 50.7% (20.8%) to 73.2% (20.9%). Pretest diagnoses were changed following CT in 43% (27 of 62) of patients. Pretest diagnoses proved to be incorrect in 52% (32 of 62), and post-test diagnoses incorrect in as many as 19% (12 of 62) of patients. All five analytic methods indicated a positive contribution for CT (all P < or = .003).

CONCLUSION

Although our illustrative case study revealed no consequential differences across the five methods, there remain substantial differences in the fundamental principles underlying them that should affect choice of analytic method when assessing diagnostic confidence.

Analysis of diagnostic confidence and diagnostic accuracy: a unified framework

Diagnostic confidence has been used as a measure of diagnostic efficacy, but this measure in isolation fails to take into account incorrect diagnoses. Conventional analytical approaches of diagnostic confidence ignore associated diagnostic accuracy. To address this limitation, we introduce a unifying framework which incorporates diagnostic confidence, changes in diagnoses and ultimate accuracy. The framework is illustrated using data from a study in which 62 patients with acute abdominal pain prospectively underwent CT. Admitting surgeons documented their diagnoses and graded their diagnostic confidences (on a 5-point scale) on admission and again after CT. Our approach, unlike conventional analyses, incorporates knowledge of final diagnoses, obtained from surgery or 6 months follow up, in assessing the impact of the test (on a 9-point scale). Changes in pre- and post-CT confidence scores were assessed by the one-sample t-test comparing against zero change, with the test statistic acting as a standardized quantity allowing comparison between our and conventional methodological approaches. Overall, 52% (32/62) of patients were misdiagnosed on admission and 19% (12/62) had incorrect post-CT diagnoses. Diagnostic confidence following CT increased significantly compared with pre-CT confidence on applying both analytical methods, although the level of statistical significance was less marked using our approach. Mean (95% confidence interval) increase in confidence under conventional analysis was 1.32 (1.03, 1.62), with standardized score t = 8.90 [p<0.0001], whereas our method yielded 0.69 (0.25, 1.13), with standardized score t = 3.12 [p = 0.003]. Although both analytical methods led to the same inference regarding the efficacy of CT in the illustrative case study presented, they differed somewhat in degree. It is conceivable that disparate conclusions may emerge in other studies and circumstances. Failure to take adequate account of incorrect diagnoses is potentially misleading. We suggest that a comprehensive analysis of diagnostic confidence requires the incorporation of diagnostic accuracy.

Do We Need Randomized Controlled Clinical Trials to Evaluate the Clinical Impact of Breast MR Imaging?

MR imaging of the breast has been shown to identify breast cancers that have gone undetected by mammography. There are a number of potential designs that can be used to further evaluate breast MR imaging, particularly with respect its impact on clinical care. Determination of whether using breast MR imaging to screen healthy individuals for breast cancer actually reduces breast cancer-specific mortality--and whether this can be accomplished at an acceptable cost--probably requires randomized, controlled clinical.

Contribution of the diagnostic test to the physician's diagnostic thinking: new method to evaluate the effect

RATIONALE AND OBJECTIVES

The purpose of this study was to develop and test a method for evaluating the effect of diagnostic tests on physicians' diagnostic thinking.

MATERIALS AND METHODS

The authors applied the method to data obtained in a previous study. The diagnoses of surgeons in the emergency department before and after contrast material-enhanced computed tomography (CT) and their certainty were collected from the cases of 125 adult patients with acute abdominal pain. When the pre- or post-CT diagnosis was not consistent with the final diagnosis, the diagnostic certainty reported by a physician was converted to a negative value (true diagnostic certainty). Change in true diagnostic certainty was calculated by subtracting the values for diagnostic certainty before CT from those after CT.

RESULTS

In 118 cases, the change in true diagnostic certainty was positive, which indicates that the CT information was beneficial for the physician's diagnostic thinking. The true diagnostic certainty before CT was 32.9% +/- 57.6 (range: -90% to 100%; 95% confidence interval: 22.7%, 43.1%) and that after CT was 73.4% +/- 37.0 (range: -80% to 100%; 95% confidence interval: 66.8%, 80.0%; P < .0001). Thus, the increase in true diagnostic certainty was 40.5% +/- 58.8 (range: -160% to 170%; 95% confidence interval: 30.1%, 69.2%).

CONCLUSION

This method may be useful for estimating the effect of diagnostic tests on physicians' diagnostic thinking in variable conditions.

The effect of pelvic MR imaging on the diagnosis and treatment of women with presumed symptomatic uterine fibroids

PURPOSE

To determine if magnetic resonance (MR) imaging significantly alters the diagnostic thinking and treatment plans of interventional radiologists during the evaluation of women for uterine fibroid embolization (UFE) for presumed uterine fibroids.

MATERIALS AND METHODS

At a single institution, interventional radiologists prospectively completed questionnaires (n = 60) before and after MR imaging was performed in their evaluation of women presenting for potential UFE. The questionnaires asked these physicians the probability (0%-100%) of their most likely diagnosis before MR imaging and after receiving the MR imaging information. They were also asked their anticipated and final treatment plans. Diagnostic confidence gains and the proportion of patients with changed initial diagnoses or anticipated management were calculated. The Wilcoxon signed-rank test was used to assess gains in diagnostic confidence.

RESULTS

MR imaging caused a mean gain in diagnostic confidence of 22% (P <.0001). MR imaging changed initial diagnoses in 11 patients (18%). Immediate clinical management changed in 13 patients (22%). UFE was not performed in 11 of 57 women (19%) who were anticipated before MR imaging to receive UFE.

CONCLUSIONS

MR imaging significantly alters the diagnoses and treatment plans of interventional radiologists evaluating women with presumed symptomatic fibroids. MR imaging should be considered in all patients before UFE.

Effect of contrast-enhanced computed tomography on diagnosis and management of acute abdomen in adults

AIM

To determine the impact of computed tomography (CT) on the diagnosis and treatment plan in patients with acute abdominal pain.

MATERIALS AND METHODS

A prospective study was undertaken in 125 adult patients presenting with acute abdominal pain (74 men and 51 women; 40.2 +/- 19.3 years; range, 18-92). Changes in diagnosis, gain in percentage diagnostic certainty and changes of treatment plan of the surgeons in the emergency department before and after CT were evaluated. Pre- and post-CT diagnoses were compared with the final diagnoses.

RESULTS

CT findings changed the initial diagnosis in 40 (32.0%) patients. The diagnostic certainty was 58.3 +/- 22.9% before CT, and its gain after CT was 21.9 +/- 18.5 points (P < 0.0001). Post-CT diagnoses were consistent with the final diagnosis in 116 patients (92.8%), while pre-CT diagnoses were correct in 89 patients (71.2%; P < 0.0001). Initial treatment plans were changed in 31 (24.8%) patients after CT. In 57 (45.6%) patients, CT information changed diagnoses and/or treatment plans. No significant differences were observed in the diagnosis, diagnostic certainty and treatment plan among four surgeons.

CONCLUSION

Contrast-enhanced CT frequently changed the clinical diagnoses with increased diagnostic certainty and the initial treatment plans.

Effect of MR angiography on the diagnosis and treatment of patients with suspected renovascular disease

PURPOSE

Although the diagnostic accuracy of renal magnetic resonance (MR) angiography is established, its effect on referring physicians is unknown. The authors prospectively measured the effect of MR angiography results on referring physicians' diagnosis and treatment (plans) of patients with suspected renovascular disease.

MATERIALS AND METHODS

Referring physicians prospectively completed questionnaires before and after MR angiography was performed during evaluation of their patients with suspected renovascular disease. The questionnaires asked them to estimate the probability (0%-100%) of their most likely diagnosis before and after receiving the imaging information. They were also asked for their anticipated and final treatment plans. The authors calculated the mean gain in diagnostic percentage confidence and the proportion of patients with changed initial diagnoses or anticipated management. A paired t-test was used to assess significance of the gains in diagnostic percentage confidence.

RESULTS

Physicians prospectively completed pre- and post-MR-angiography questionnaires for 30 patients. MR angiography improved mean diagnostic certainty by 35% (P < .0001). MR angiography changed physicians' initial diagnoses in 12 patients (40%). Anticipated treatment plans were changed in 20 patients (67%). Invasive procedures were avoided in eight patients (27%).

CONCLUSION

MR angiography has a substantial effect on the diagnostic and therapeutic decision-making of physicians managing patients with suspected renovascular disease.

Impact in the emergency department of unenhanced CT on diagnostic confidence and therapeutic efficacy in patients with suspected renal colic: a prospective survey. 2000 ARRS President's Award. American Roentgen Ray Society

OBJECTIVE

Our objective was to evaluate the impact of unenhanced CT on clinician diagnostic confidence and therapeutic efficacy in emergency department patients with clinically suspected renal colic.

SUBJECTS AND METHODS

Questionnaires were completed on 93 patients who were referred to the radiology department with clinically suspected renal colic. We prospectively surveyed the clinician's diagnostic confidence and treatment plan before and after unenhanced abdominal and pelvic CT.

RESULTS

Fifty-six patients (60%) had positive findings for calculi, 20 patients (22%) had normal findings, and alternative diagnoses were found in 17 patients (18%). The clinician's diagnostic certainty of stones before CT was variable with the largest frequencies at 41-60% (n = 30) and 71-90% (n = 35). The diagnostic certainty of stones after CT showed movement toward either less than or equal to 10% (n = 25) or greater than or equal to 91% (n = 51). The mean change in diagnostic confidence was 34%. Fifty-seven patients (61%) had a change in treatment plan. Specifically, the need for urology consultation as the initial treatment plan was reduced from 24 patients to one patient. Plans for admissions suggested before CT (n = 11) were nearly cut in half (n = 6) after imaging. Lastly, seven patients who would have initially been discharged were admitted to the hospital after imaging.

CONCLUSION

CT significantly increased emergency department clinician diagnostic confidence and altered initial treatment decisions in patients with suspected renal colic. Most often, CT confirmed a ureteral stone and allowed appropriate discharge or urologic intervention. In a smaller subset of patients, CT established a significant alternative diagnosis that allowed the prompt initiation of appropriate treatment.

Impact of MR angiography on the diagnosis and management of renal transplant dysfunction

PURPOSE

To evaluate the impact of magnetic resonance angiography (MRA) on referring physicians' diagnoses and treatment of patients with renal transplant dysfunction.

MATERIALS AND METHODS

Physicians of the renal transplant service at the authors' university hospital prospectively completed questionnaires before and after MRA was performed in the evaluation of renal transplants. The questionnaires asked physicians to estimate the probability (0%-100%) of their most likely diagnosis before and after receiving the imaging information. They were also asked to provide their anticipated and final treatment plans. The authors calculated the mean gain in diagnostic percentage confidence and the proportion of patients with changed initial diagnoses or anticipated management. A paired t test was used to assess statistical significance of the gains in diagnostic percentage confidence.

RESULTS

Pre-MRA and post-MRA questionnaires were prospectively completed on 31 separate patients. The mean gain in diagnostic certainty percentage from MRA was 33% (95% CI, 19%-51%; P < .001). MRA changed physicians' initial diagnoses in 20 patients (65%; 95% CI, 47%-79%). Immediate clinical management changed in 16 patients (52%; 95% CI, 35%-68%). Invasive procedures were avoided in 12 patients (39%).

CONCLUSION

MRA has considerable impact on referring physicians' diagnoses and treatment of patients with suspected renal allograft dysfunction.