Learning objectives
To review the MR anatomy of the temporal lobe,
especially medial region.
To discuss optimal MRI temporal lobe protocol.
To describe primary as well as secondary magnetic resonance features of MTS.
To discuss the role of quantitative volumetric MRI,
T2 relaxometry,
MR spectroscopy and functional imaging methods in the presurgical workup of temporal lobe epilepsy (TLE).
Background
•Approximately 30% of patients with epilepsy do not respond to adequate medical treatment.
They are then said to havemedically refractory or intractable epilepsy.In these patients,
the opinion of surgical treatment needs to be considered.
•Hippocampal sclerosis is the most common pathology in patients undergoing temporal lobe surgery.
•Identifiable pathology ,such as Hippocampal sclerosis,
is associated with a good outcome from surgery and its reliable preoperative diagnosis is important for the assessment and management of patients with intractable partial epilepsy.
Imaging findings OR Procedure details
MR anatomy of Medial Temporal Lobe
•NORMAL ANATOMY
•Because of its different functions and organization,
the temporal lobe may be divided into lateral and medial parts.
•The neural structures that constitute the mesial temporal lobe are the parahippocampal gyrus,
uncus,
hippocampus,
fimbria,
dentate gyrus,
and amygdala.
•The hippocampus is a curved structure on the medial aspect of temporal lobe consisting of complex U-shaped layers of the dentate gyrus and cornu ammonis,
which are interlocked together.
•The cornu ammonis blends into the subiculum,
which forms the...
Conclusion
1.
MRI forms the mainstay for structural and functional neuroimaging in patients with epilepsy.
2.
With increasing availability of newer techniques and MR sequences,
the sensitivity and specificity of detecting epileptogenic lesion on MRI has increased.
3.
The MRI demonstration of a lesion very much helps in further presurgical evaluation.
In patients with negative MRI,
PET and SPECT may be used as complimentary tools in the presurgical workup.
4.
In the recent years,
advances in neuroimaging have helped to understand the pathophysiology of epilepsy better...
Personal Information
Dr.
Paramdeep Singh MD
Department of Radio-diagnosis
MM Institute of Medical Sciences and Research
Maharashi Markandashwar University
Mullana (Ambala)
Haryana. Pin-133207
[email protected]
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