SPECT and epilepsy with continuous spike waves during slow-wave sleep

Area of Science:

• Neurology
• Neuroimaging
• Epilepsy Research

Background:

• Continuous spike waves in slow-wave sleep (CSWS) is an epilepsy syndrome characterized by specific EEG abnormalities.
• Understanding the underlying neurobiological changes in CSWS is crucial for diagnosis and management.
• Cerebral blood flow (CBF) studies can provide insights into brain function in epilepsy.

Purpose of the Study:

• To evaluate the utility of single photon emission computed tomography (SPECT) in identifying focal cortical abnormalities in CSWS.
• To correlate SPECT findings with electroencephalogram (EEG) data in patients with CSWS.
• To investigate the relationship between the duration of the CSWS phase and the extent of cortical dysfunction.

Main Methods:

• Ten patients diagnosed with CSWS underwent SPECT imaging using 99mTc-HMPAO.
• SPECT was performed during drowsiness to assess regional CBF.
• SPECT results were compared with concurrent EEG findings, focusing on the localization of paroxysmal abnormalities.

Main Results:

• SPECT revealed areas of reduced CBF in four cases, corresponding to the predominant EEG discharge sites.
• In two cases, hypoperfusion areas did not align with EEG findings, and four cases showed negative SPECT results.
• Positive SPECT findings were more frequent in patients with a CSWS phase duration of at least one year, suggesting a more significant cortical disorder with prolonged disease duration.

Conclusions:

• SPECT can detect focal cortical areas of decreased CBF in CSWS, generally correlating with EEG abnormalities.
• A longer duration of the CSWS phase appears to be associated with more pronounced cortical dysfunction, as evidenced by hypoperfusion.
• SPECT imaging may serve as a valuable tool in characterizing the neurobiological underpinnings of CSWS.