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reversible cerebral vasoconstriction syndrome ( rcvs ) is characterized by severe headaches , with or without other acute neurological symptoms , and by the diffuse segmental constriction of the cerebral arteries that resolves spontaneously within three months ( 1 ) .
in addition to the simple vasoconstriction demonstrated by magnetic resonance angiography ( mra ) , rcvs - associated abnormalities , including posterior reversible encephalopathy syndrome ( pres ) and/or ischaemic / haemorrhagic strokes ( accompanied by rcvs ) , have also been demonstrated by magnetic resonance imaging ( mri ) .
however , cases of rcvs with transient splenial lesions ( tsl ) detected by mri are rare ; only two such cases have been reported previously ( 2,3 ) .
a 28-year - old woman with no history of migraine or any other disease developed a thunderclap headache immediately after an uncomplicated pregnancy and spontaneous vaginal delivery at 40 weeks of gestational age .
the patient had a normal blood pressure during pregnancy , indicating that she did not have preeclampsia .
she had a history of normal uncomplicated vaginal delivery at 21 and 25 years of age ; this was her third pregnancy .
she had not undergone epidural anaesthesia or been given any vasoactive drugs . although the patient 's headache improved the day after disease onset , it re - emerged 17 days after onset , and again improved 18 days after onset .
brain diffusion - weighted imaging showed an intensified signal in the splenium of the corpus callosum ( figure a ) .
the apparent diffusion coefficient ( adc ) indicated a low signal in the same area ( figure b ) .
mra showed segmental constriction of the left middle cerebral artery and bilateral posterior cerebral arteries ( figure d ) .
a cerebrospinal fluid analysis revealed an opening pressure of 100 mm h2o , no red blood cells , 1 white blood cell / mm , a glucose level of 62 mg / dl and a protein level of 17 mg / dl .
her symptoms did not worsen or relapse , despite not using either calcium - channel blockers or any other agents .
mri and mra 20 days after the first examination were normal with a complete resolution of the tsl and all other vascular abnormalities ( figure c and f ) .
( a ) brain axial diffusion - weighted images ( dwi ) at first examination ( 19 days after onset ) showing signal hyperintensity in the splenium of the corpus callosum .
( b ) the apparent diffusion coefficient indicating a low signal in the same area .
( c ) dwi at 9 days after the first examination showing splenial lesion recovery .
( d - f ) serial magnetic resonance angiography showing focal constriction of the bilateral posterior cerebral arteries and the middle cerebral arteries ( arrow head ) and serial recovery ( d , at first examination ; e , 9 days after the first examination ; and f , 20 days after the first examination ) .
based on the typical and main symptoms of rcvs , our patient experienced a thunderclap headache immediately after delivery .
the mra abnormalities of rcvs and mri abnormalities of tsl with serial recovery in our patient indicated an association between delivery and the development of both rcvs and tsl .
rcvs - associated mri abnormalities include three types of stroke ( cerebral infarction , convexity subarachnoid haemorrhage , and intracerebral haemorrhage ) and reversible brain edema such as pres ( 1 ) . in our case ,
the decreased adc indicated cytotoxic oedema clearly distinct from pres , as the adc levels do not decrease in pres .
only two cases of rcvs with tsls have been reported to date , and both cases , like the present case , occurred postpartum ( table ) ( 2,3 ) .
although the timing and clinical features , such as signs , symptoms and serial mri findings varied in these three cases , they indicated that delivery may be strongly associated with the development of both tsls and rcvs .
the important difference between the previously reported two cases and our case was the presence of neurological symptoms / sings .
our patient did not develop either seizures or neurological deficits and also had a normal blood pressure .
postpartum / peripartum patients with headaches , seizure , dysarthria , or eclampsia are immediately suspected of having neuroimaging abnormalities and require an urgent diagnostic work - up to identify the cause .
meanwhile , rcvs cases presenting with headache only , like in our case , might be overlooked or underestimated .
postpartum tsls are also rare ; however , a few cases of tsls ( without rcvs ) after pregnancy have been reported ( 5 - 8 ) .
tsls are associated with a variety of disorders , including infection , antiepileptic drug withdrawal , high - altitude cerebral oedema , metabolic disturbance and others ( 9 ) . despite the large number of aetiologies ,
it remains uncertain as to why tsls selectively occur in the splenium ; moreover , the exact pathogenesis of tsls remains elusive .
the splenium differs from other parts of the corpus callosum with respect to its vascular supply ; the rostrum , genu and trunk , which constitute the anterior part of the corpus callosum , are supplied by branches of the artery originating from the anterior circulation , whereas the splenium is supplied by both the anterior and posterior branches of the artery ( 10 ) .
however , because of the reversibility of the lesions and the absence of any other lesions in vascular distributions , it is unlikely that tsls are the result of ischaemia ( 11 ) . it has been postulated that the splenium has a specific vulnerability to excitotoxic injury in metabolic diseases , making it selectively involved in differential pathological events ( 12 ) .
another possible explanation for such tsl development is that it may be related to a relative  lack of adrenergic tone , making it susceptible to hypoxic vasodilation and autoregulation failure with resultant hyperperfusion ( 9,13 ) . on the other hand ,
transient  failure of regulation of cerebral arterial tone with sympathetic hyperactivity seems to play a role in rcvs development ( 1 ) .
although hormonal and metabolic changes during the peripartum period can contribute to the pathogenesis , of rcvs and tsl , a transient failure of regulation of arterial tone after delivery might be the common mechanism underlying both tsl and rcvs development .
previously reported and present case(s ) of reversible cerebral vasoconstriction syndrome with transient splenial lesion .
gtc : generalized tonic - clonic seizure , sd : speech disturbance , pres : posterior reversible encephalopathy syndrome , sv : segmental vasoconstriction demonstrated by mra , tsl : transient splenial lesion , nd : not described , mri : magnetic resonance imaging .
patients with tsls are often asymptomatic , and these lesions are incidentally noticed during mris performed for other reasons .
moreover , rcvs presenting only with a headache is also common , and a diagnosis of rcvs depends on the mra findings .
the actual incidence of rcvs with tsls or postpartum tsls is therefore unknown ; rcvs with tsls may be overlooked and might therefore be a more common condition than is currently thought .
reversible cerebral vasoconstriction syndrome ( rcvs ) is characterized by segmental vasospasm and it is often accompanied by either posterior reversible encephalopathy syndrome or stroke . however , other mri abnormalities have rarely been reported . a 28-year - old woman presented with a thunderclap headache immediately after delivery 
 ; mri showed segmental vasoconstriction and an abnormal signal in the splenium of the corpus callosum . 
 neuroimaging abnormalities normalized 20 days after the first examination . 
 only two cases of rcvs with transient splenial lesions ( tsl ) have so far been reported . 
 both cases occurred postpartum like ours , indicating that delivery may be a trigger for the development of both tsls and rcvs .