Detection of partial loss of hippocampal striation at 1.5 Tesla magnetic resonance imaging

OBJECTIVES: Partial loss of hippocampal striation (PLHS) is recently described in 3 T and 7 T MR imaging as a sensitive indicator of hippocampal sclerosis. Primary objective: We described the demographic characteristics of the population with seizure disorder having PLHS at 1.5 T MR imaging and tried to see the relation of PLHS to the classic signs of hippocampal sclerosis. Secondary objective: PLHS was also looked for in a small control population that had no seizure history. METHODS: This retrospective study had the approval of the institutional review board. In patients demonstrating PLHS on oblique coronal T2-weighted images, the following were recorded: age, sex, EEG findings, side of PLHS, hippocampal atrophy and high signal intensity of the hippocampus. In control population, the following were recorded: age, sex, presence/absence of PLHS and indication for imaging. RESULTS: The 116 PLHS subjects (age range 2–73 years) included 62 males and 54 females. Sixty-six (56.9%) of our PLHS subjects were less than 18 years of age: 44 (37.9%) under the age of 12 years and 22 (19%) of 12–18 years of age. Classic signs of hippocampal sclerosis were found in only 7 (6%) of the 116 subjects showing PLHS. All patients with classic signs showed PLHS on the same side. Of the control population (25 subjects, age range 3–76 years, 17 males and 8 females), one showed PLHS—he was a treated case of CNS lymphoma with gliotic changes, though there was no history of seizure. CONCLUSION: PLHS is demonstrated at 1.5 T in both adult and paediatric population in this article and is much more common than the classic signs of hippocampal sclerosis (increased signal intensity and volume loss).