Neuro-Radiology Case Review: Challenge Yourself with the Imaging DDX

This session is intended to be a supplemental case-based review of neuro-radiology pearls and pitfalls as; they relate to imaging in neuro-ophthalmology. A particular focus of this session will be understanding; the typical imaging sequences used in imaging of neuro-ophthalmological disorders, as well as gaining; understanding of how certain newer imaging modalities (notably arterial spin label perfusion imaging); might be applied. As cases are presented, a focus will also be on working through an appropriate; differential diagnosis and understanding why or why not a particular consideration in the differential; diagnosis is a good fit

Test-retest data, comprising multiple T1-weighted MRI brain volumes.

<p>Data accompanying manuscript, "Reliability of Brain Volume Measurements: A Test-Retest Dataset"</p

Role of Diffusion-Weighted MRI in Clival Chordoma

Purpose: Chordoma is a rare notochordal tumor with a proclivity for the skull base and sacrococcygeal region. Poorly differentiated chordoma (PDC), as reported in the pediatric literature, displays more aggressive behavior compared with classic chordoma (CC). We investigated the role of diffusion-weighted imaging (DWI) MRI in evaluating these chordoma types. Methods: Nine patients with clival chordoma (median age, 9.5 years; range, 22 months to 60 years) who had pretreatment DWI MRI (echo planar imaging technique, b = 1000 s/mm2, 3 directions) were retrospectively reviewed, after IRB approval. The apparent diffusion coefficient (ADC) of the solid portions of the tumor, exclusive of hemorrhage or cyst, was measured using the region of interest method. Immunohistochemical staining for nuclear Brachyury was performed to confirm chordoma diagnosis. Staining with SMARCB/INI-1 was performed to distinguish chordoma types. The ADC values of clival chondrosarcoma were assessed in two patients for comparison. Results: All cases of PDC (n = 3) were seen in children. The diagnosis of CC (n = 6) was made in 4 adults and 2 children. There was a significant difference between ADC values of PDC (891 ± 127 mm2/s) and CC (1491 ± 167 mm2/s) (P = 0.001). Chondrosarcoma showed the highest ADC (1756 ± 47 mm2/s), but statistical significance was not assessed due to low sample size. Enhancement characteristics did not distinguish these tumor types. Conclusions: Diffusion MRI may serve as a useful adjunct in assessing clival tumors, particularly in identifying poorly differentiated chordoma. A larger series incorporating diffusion MRI of clival tumors may further define its role in evaluating other tumors such as chondrosarcoma

Role of Diffusion-Weighted MRI in Clival Chordoma

Purpose: Chordoma is a rare notochordal tumor with a proclivity for the skull base and sacrococcygeal region. Poorly differentiated chordoma (PDC), as reported in the pediatric literature, displays more aggressive behavior compared with classic chordoma (CC). We investigated the role of diffusion-weighted imaging (DWI) MRI in evaluating these chordoma types. Methods: Nine patients with clival chordoma (median age, 9.5 years; range, 22 months to 60 years) who had pretreatment DWI MRI (echo planar imaging technique, b = 1000 s/mm2, 3 directions) were retrospectively reviewed, after IRB approval. The apparent diffusion coefficient (ADC) of the solid portions of the tumor, exclusive of hemorrhage or cyst, was measured using the region of interest method. Immunohistochemical staining for nuclear Brachyury was performed to confirm chordoma diagnosis. Staining with SMARCB/INI-1 was performed to distinguish chordoma types. The ADC values of clival chondrosarcoma were assessed in two patients for comparison. Results: All cases of PDC (n = 3) were seen in children. The diagnosis of CC (n = 6) was made in 4 adults and 2 children. There was a significant difference between ADC values of PDC (891 ± 127 mm2/s) and CC (1491 ± 167 mm2/s) (P = 0.001). Chondrosarcoma showed the highest ADC (1756 ± 47 mm2/s), but statistical significance was not assessed due to low sample size. Enhancement characteristics did not distinguish these tumor types. Conclusions: Diffusion MRI may serve as a useful adjunct in assessing clival tumors, particularly in identifying poorly differentiated chordoma. A larger series incorporating diffusion MRI of clival tumors may further define its role in evaluating other tumors such as chondrosarcoma

Prognostic Value of A Qualitative Brain MRI Scoring System After Cardiac Arrest

BACKGROUND AND PURPOSETo develop a qualitative brain magnetic resonance imaging (MRI) scoring system for comatose cardiac arrest patients that can be used in clinical practice. METHODSConsecutive comatose postcardiac arrest patients were prospectively enrolled. Routine MR brain sequences were scored by two independent blinded experts. Predefined brain regions were qualitatively scored on the fluid-attenuated inversion recovery (FLAIR) and diffusion-weighted imaging (DWI) sequences according to the severity of the abnormality on a scale from 0 to 4. The mean score of the raters was used. Poor outcome was defined as death or vegetative state at 6 months. RESULTSSixty-eight patients with 88 brain MRI scans were included. Median time from the arrest to the initial MRI was 77 hours (IQR 58-144 hours). At 100% specificity, the cortex score performed best in predicting unfavorable outcome with a sensitivity of 55%-60% (95% CI 41-74) depending on time window selection. When comparing the cortex score with historically used predictors for poor outcome, MRI improved the sensitivity for poor outcome over conventional predictors by 27% at 100% specificity. CONCLUSIONSA qualitative MRI scoring system helps assess hypoxic-ischemic brain injury severity following cardiac arrest and may provide useful prognostic information in comatose cardiac arrest patient