الفهرس 
TitleOnly 14 pages are availabe for public view
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Abstract
Intracerebral Hemorrhage (ICH) is a severe medical condition, which may develop quickly into a life-threatening situation, and thereby requires prompt medical attention. ICH is responsible for up to 15% of all strokes and is associated with a high rate of mortality.
Diagnosis of ICH involves neuroimaging options; CT has traditionally been used in radiologic workup of ICH. However, numerous studies have demonstrated that MRI is more efficient for detecting and localizing ICH, which can now be carried out in real-time in the acute clinical setting.
MRI has emerged as a highly sensitive tool for the detection of both chronic and acute hemorrhage. It is well established that when blood extravasates into brain tissue, hemoglobin becomes deoxygenated. Deoxyhemoglobin, because of the presence of unpaired electrons, is a paramagnetic substance that produces a local, nonuniform magnetic field, resulting in rapid dephasing of proton spins in T2-weighted sequences.
Sensitivity for the detection of deoxy- hemoglobin-induced signal loss is greatest for partial flip angle (i.e. gradient echo) and echo-planar sequences, Diffusion Weighted MRI (DW-MRI) has become an established part of neuroimaging and is used to diagnose and characterize several neurologic disorders, and provides image contrast that is different from that provided by conventional MR techniques.
This work aimed to evaluate the role of MRI diffusion weighted imaging in particular b0 value in detection and characterization of intracranial hemorrhage.
Among all consecutive patients admitted to Dar Elfouade Hospital. Fifty patients will be selected from among those fulfilling the following criteria: (1) Intracranial hematoma unrelated to neoplasm. (2) Those patients performed CT which revealed an Intracranial Haemorrhage with time interval between the CT and MRI examinations 2–4 h.
The magnetic resonance T1and T2 and FLAIR weighted images -axial planes- were acquired with a number of slices covered the whole brain without contrast injection, diffusion weighted images were obtained according to Doris et al and axial gradient GRE T2* sequence (425/15/1, 208 flip angle, 256 x 160 matrix, 1:45-minute acquisition time) was acquired in all cases
All MR images were reviewed retrospectively by a neuroradiologist blinded to the clinical data. The b0 EPI and GRE images from each subject were evaluated at separate sessions in a random order. Subsequently, the b0 EPI and GRE images were analyzed side-by-side, in conjunction with the DWI scans, for relative conspicuity of hemorrhage and diagnostic certainty.
Summary & Conclusion
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The results of the present work are:
Patients with hyper-acute ICH, the signals at the center of the hematoma were hyper-intense at DWI, iso-intense on T1-weighted images, and heterogeneously hyper-intense on T2-weighted and FLAIR images. At DWI, focal marked hypo- intensity was seen in all patients at some portion of the hematoma, which was surrounded by a hyper-intense rim.
Patients whose hematomas were acute or early sub-acute, the signal intensity appeared markedly hypo-intense on diffusion-weighted, T2-weighted, FLAIR, and gradient echo images
Patients with late sub acute hematomas at this stage, diffusion-weighted, T1- and T2-weighted, and FLAIR images showed marked hyper-intensity.
Four of the eight chronic hematomas appeared homogeneous and markedly hypo-intense, and the remaining four showed an isointense center surrounded by a hypo-intense rim.
GRE is more sensitive and affords greater diagnostic certainty than b0 EPI in identifying the presence of hemorrhage.
Conclusion
GRE is more sensitive and affords greater diagnostic certainty than b0 EPI in identifying the presence of hemorrhage. Therefore, GRE may be an important pulse sequence in emergency brain MR studies for acute stroke. In addition to characterizing various acute hemorrhagic lesions, GRE images reveal chronic petechial hemorrhage that is, in the majority of cases, not apparent on b0 EPI scans. Knowledge of these chronic hemorrhagic lesions may prove in the future to have a clinical implication in choice of therapy.