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 right side for one day. Right hand
clumsiness with unfamiliarity with her right hand and numbness were also complained.
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 presence of low density of corpus callosum,
more obvious at genu and body. Brain MRI showed acute ischemic infarct of the
entire corpus callosum. In 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.
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 clinical
improvement of the patient.