[Double inversion recovery sequence in temporal lobe epilepsy: preliminary results].

Area of Science:

• Neuroimaging
• Epilepsy Research
• Radiology

Background:

• Temporal lobe epilepsy (TLE) diagnosis relies on identifying lesions in the temporal lobe, particularly the hippocampus.
• Conventional MRI sequences like FLAIR and T2W have limitations in detecting subtle abnormalities.
• Double inversion recovery (DIR) is a hybrid MRI sequence combining FLAIR and STIR properties, potentially offering enhanced contrast for specific lesions.

Purpose of the Study:

• To evaluate the diagnostic superiority of the DIR sequence compared to conventional FLAIR and T2W sequences for identifying mesial temporal sclerosis and other temporal lobe lesions in TLE patients.
• To test the hypothesis that DIR provides higher sensitivity for detecting lesions with low T2 contrast.

Main Methods:

• A comparative study involving 33 TLE patients and 10 healthy controls.
• Acquisition of coronal MRI images of the temporal lobes and hippocampus using DIR, FLAIR, and T2W sequences.
• Qualitative assessment of lesion sensitivity, hippocampal lesion detectability, and artifacts; quantitative analysis of signal-to-noise and contrast-to-noise ratios.

Main Results:

• DIR sequence demonstrated higher contrast-to-noise ratios compared to T2W and FLAIR sequences.
• While T2W had higher signal-to-noise ratios, DIR showed comparable overall sensitivity for lesion detection.
• DIR was less sensitive to hippocampal atrophy due to cerebrospinal fluid artifacts but showed high sensitivity for mesial temporal sclerosis-like lesions and solid masses.

Conclusions:

• Despite susceptibility to artifacts, the DIR sequence exhibits high sensitivity for detecting mesial temporal sclerosis and related hippocampal lesions.
• DIR may serve as a valuable supplementary MRI sequence when conventional methods reveal suspicious findings without clear hippocampal atrophy.