Isolated diffuse corpus callosum infarction is a rare condition due to
its abundant blood supply, vessel branch orientation and anterior cerebral
artery-posterior cerebral artery anastomoses. Damage to the corpus callosum
usually produces disturbance of higher brain function including callosal
disconnection syndrome. However, no previous studies have described the
electroencephalographic change in corpus callosum infarction patient presented
with alien hand syndrome and limb apraxia.
A 55-year-old right-handed female was admitted due to gait unsteadiness
with lateropulsion to the right side for one day. She also experienced right-hand
clumsiness with unfamiliarity with her right hand and numbness. Besides, her
husband noted her response became mildly slow. Her past history included
diabetes mellitus with regular medication control. Neurological examination revealed
decreased pinprick sensation over right lower face and leg, mild right weakness
without dysmetria and right lateropulsion. Brain CT revealed the presence of low density of corpus callosum, more obvious at genu and
body. Brain MRI
showed acute ischemic infarct of the entire corpus
addition, MRA showed non-visualization of bilateral
anterior cerebral arteries at the origins. Laboratory exam showed high total
cholesterol, LDL, and HbA1c. During hospitalization, movement interference from
her right hand was found while she reached something by left hand. She
described “her right hand was not under control of the mind”. Left-hand
agraphia and apraxia were also noted. Electroencephalography revealed intermittent
synchronous or asynchronous sharp waves over bilateral central posterior areas.
Follow-up electroencephalography one month later showed less frequent and
lower-voltage of previous sharp waves. The symptoms of right alien hand
syndrome and left apraxia also improved to some extent.
Electroencephalographic changes in the patient with diffuse corpus
callosum infarction may correlate with clinical presentations of callosal disconnection
syndrome. Besides, electroencephalography may be a useful indicator corresponding
to the clinical improvement of the patient.