Non-contrast enhancement of brachial plexus magnetic resonance imaging with compressed sensing.

PURPOSE: To observe the quality of brachial plexus (BP) images obtained from magnetic resonance imaging (MRI) with 3D T2 STIR SPACE sequence and compressed sensing (CS) and to compare the results with BP images from the same sequence without CS. METHODS: In this study, compressed sensing was applied to acquire non-contrast BP images from ten healthy volunteers with 3D T2 STIR SPACE sequence to shorten acquisition time without sacrificing image quality. The acquisition time of scanning with CS was compared to that without CS. The quantitative signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated and compared using paired t-test to determine the quality of images with and without CS. The qualitative assessment by three experienced radiologists was performed using a scoring scale from 1 (poor) to 5 (excellent) and analyzed for interobserver agreement on image quality. RESULTS: The increasing SNR and CNR of images with CS were found in nine regions of BP images (p < 0.001) with faster acquisition time. The result of paired t-test (p < 0.001) illustrates the significant difference between images with CS compared to images without CS. The assessment of observers also shows higher scores for images with CS compared to images without CS. CONCLUSIONS: This study demonstrates that CS can effectively increase the visibility of images and image boundaries, SNR, and CNR of BP images obtained with 3D T2 STIR SPACE sequence with the good interobserver agreement and within clinically optimal acquisition time compared to images from similar sequence without CS.

Relationship between neutrophil count in cerebrospinal fluid and cerebral infarct appearance in head MRI on tuberculous meningitis patients.

Objectives: To determine the relationship between neutrophils count in cerebrospinal fluid and cerebral infarction in head magnetic resonance imaging (MRI) on patients with tuberculous meningitis. Methods: A diagnostic study was done on patients with tuberculous meningitis (TBM) who underwent head MRI examination and cerebrospinal fluid analysis at Dr. Hasan Sadikin General Hospital from January 2015 to September 2016. TBM was diagnosed by Mycobacterium tuberculosis isolation from cerebrospinal fluid. Cut-off value of neutrophil count was determined using receiver operating characteristics (ROC) curve. Conformity test was done using Kappa test. Results: Thirty seven subjects were recruited in this study. Higher neutrophil count in CSF was observed on subjects with cerebral infarction (p < 0.05). Cut-off value of neutrophil count in CSF was determined as > 41 %. There was a moderate conformity between higher neutrophil count in CSF and cerebral infarction appearance in MRI (p < 0.05, Kappa score 0.529). Conclusion: Higher neutrophil count was associated with the appearance of cerebral infarct in head MRI on adult patients with tuberculous meningitis.