Horizontal nystagmus and multiple sclerosis using 3-Tesla magnetic resonance imaging.

BACKGROUND: Nystagmus in patients with multiple sclerosis (MS) is generally attributed to brainstem disease. Lesions in other regions may result in nystagmus. The identification of these other sites is enhanced by using 3-Tesla magnetic resonance imaging (3TMRI) due to increased signal-to-noise ratio. OBJECTIVE: We sought to evaluate the distribution of structural lesions and disruption of tracts in patients with horizontal nystagmus secondary to MS using 3TMRI. METHODS: Twenty-four patients (20 women, 4 men; age range 26-55 years) with horizontal nystagmus secondary to MS underwent 3TMRI brain scans; and 18 patients had diffusion tensor imaging (DTI) for tractography. RESULTS: Nystagmus was bidirectional in 11, right-sided in 6 and left-sided in 7. We identified 194 lesions in 20 regions within the neural integrator circuit in 24 patients; 140 were within the cortex and 54 were within the brainstem. Only two patients had no lesions in the cortex, and 9 had no lesions in the brainstem. There was no relationship between side of lesion and direction of nystagmus. Thirteen of 18 (72 %) had tract disruption with fractional anisotropy (FA) values below 0.2. FA was significantly lower in bidirectional compared to unidirectional nystagmus (p = 0.006). CONCLUSION: In MS patients with horizontal nystagmus, lesions in all cortical eye fields and their descending connections were evident. Technical improvements in tractography may help identify the specific site(s) resulting in nystagmus in MS.

Radiological error--an early assessment of departmental radiology discrepancy meetings.

This study reviews cases discussed at radiology departmental discrepancy meetings and retrospectively determines patterns of radiological error. All cases discussed since the inception of our departmental discrepancy meetings (20-month period) were reviewed. Discrepancies were classified according to the RADPEER score. The imaging method from which the discrepancy arose was recorded. An attendance log at all meetings was kept. 111 discrepancies were identified in 104 patients. 52 (46.85%) of the 111 discrepancies arose in relation to plain film radiography, 46 (41.44%) to CT, 11 (9.9%) to magnetic resonance imaging, and 2 (1.8%) to nuclear medicine examinations. Several repeating discrepancies were identified. Discrepancy Meetings facilitate collective learning from radiology discrepancies and thereby improve patient safety. They provide radiologists with the invaluable opportunity to reconsider current practice and when indicated to change and improve practice. The majority of discrepancies are due to false negative interpretation and occur primarily in plain film and CT reporting.