Intrauterine fetal death of one of twins,c oexisting with 
hydranencephaly in the surviving co-twin: A case report 
*J. A. Olowul, I. A. Lagmu', 0.0.T ong01 and M. Atahbiz 
Departments of Pcaediatrics' and Radiology2 
College of Medicine, University of Ib& University College Hospital, 
Zbarian, Nigeria 
E-mail: ilagunju@yahoo.co.uki lagauyauyu@comui~edu.ng 
s==Y infarction and damage to the intracranial structures 
Hydrauencephaly, a relatively rare malformationo f supplied by these ~essels.7.~ 
the brain, is cbm&rkd by a b a mo fthe cerebral hemi- b) Intrauterine infections by Tomplasma gondii, 
spheres and their replacement by sacs filled with cer- Cytomegolovirus, and Herpes simplex virus, caus- 
ebrospinal fluid. ing necrotizing vasculitis or encephalitis 9.10 
It is one of the recognised forms of intrammial mal- C) Release of thromboplastic material from a deceased 
formations assodated with intrauterine f e w  co-twin with resultant liquefaction of the normal brain 
one oftwins in monochorionic twin gestation. This report tissue in the surviving twin."J2 
illustrates the development ofhydranencephaly in a sur- An increased incidence has been reported in smok- 
viving twin sequel to intrauterine fetal demise of the co- ing mothers.13 An infant with hydranencephaly may ap- 
twin. pear nonnal at birth, the infant's head size and spontane- 
ous reflexes such as sucking, swallowing, rrying and limb 
Key words: Hydraneneepturly, Twins, Intrauterine fetal movements may all appear normal.' However, as the child 
death. grows, the neurological deficits become evident. These 
include irritability, generalised spasticity, seizures, deaf- 
R b m C  ness, visual impairment, intellectual deficits and failure to 
Hydranenckphalie, une malfomation du cerveau relative- acquire the expected developmental milestones.' 
ment rare, est caractkris6e par l'absence d'h6misphCres This report illustrates the development of hydranen- 
&'braux et leur remplacement par des sacs remplis avec le cephaly in a previously normal fetus, one of a set of twins, 
fluide c6r6brospinal. C'est l'une des formes connues des following intrauterinef etal death of the co-twin. 
malfomations intracraniCnnes li&s ii la demise fetale 
intrauterine de l'un des jumeaux dans la gestation Casereport 
monochorionique dej umeau. Cette communication illustre Baby BT, a preterm female infant was delivered to a 
le dkveloppement d'hydranenc6phalie chez unjumeau 33year old G2Pz4mothera t a gestational age of 34 weeks. 
survivant B la suite de la demise foetale intrauteri2mne du The mother was neither hypertensive nor diabetic; she 
co-jumeau. was not a smoker and had never ingested alcohol. She 
booked for routine antenatal care at a tertiary health cen- 
Intrdudion tre at a gestational age of 23 weeks. There was no history 
Hydranencephaly is a congenital malformation of the of exposure to irradiation in pregnancy. The only drugs 
central nervous system in which the cerebral hemispheres taken in pregnancy were routine haematinics; oral Ferrous 
are missing.' It is associated with a total or near total Gluconate 200mg thrice daily and oral Folic acid 5mg daily. 
destruction of the cerebral cortex and the basal ganglia, The mother had no febrile illness or exanthematous skin 
the thalami and lower brain centres are typically pre- rash in pregnancy. 
~erved.'.~. It is a rare condition occurring in about 1p er The first abdominal ultrasound in the index pregnancy 
10,000 births or less, and found in 0.2% of infant autop- was when she booked at 23weeks of gestation. This con- 
sies3v4. Hydranencephaly is characterised by absence of firmed monochorionic twin gestation, however only one 
the cerebral hemispheres and presence of a sac-like struc- of the fetuses was alive while the other was found to have 
ture containing cerebrospinal fluid (CSF) ,s urrounding the died. The living fetus was found to be normal with no 
brain. Facial features are also uniformly normal and this abnormalities of the intracranial structures and no other 
distinguishes hydranencephaly from other major central congenital malformations. The pregnancy was therefore 
nervous system an~malies.~ managed conservatively in order to allow for maturity of 
Hydranencephaly is considered to be the result of a the surviving twin by the time of delivery. She continued 
destructive process or lesion in a previously normal braia6 on routine haematinics and twice weekly monitoring of 
Various theories have been proposed with regards to the her clotting profile. Fetal well being was monitored by fe- 
aetiqlogy of hydranencephaly. These include: tal kick charts and was found to be normal. 
a) Bilateral occlusion ofthe supraclinoid segment of the A repeat abdominal ultrasound at the 31" week of 
internal carotid arteries resulting in severe ischaemia, pregnancy revealed abnonnal intracranial structures in the 
*Correspondence 
WAN VOL. 25 NO 3. .JULY - SBTl%BW 2006 
UNIVERSITY OF IBADAN LIBRARY
lntmuterine fetal death of one of twins, coexisting with hpdruutencephaly in the suniving co-twin: A case report - JAO lowu et a1 
Figure 1 Arial CT scan of the brain. Note the absence of the cerebmi Figure irial CT scan of the brain showing absence of the 
k & p h a ndtheir r e p l a c e ~ ~ b ~ 3TWherde b alsoanabsenceo f a *urn- cerebral hemispheres and an intact falr cerebri. 
ferentialh of cerebdtissue which is usually seen in hydrocephalus. Thepos- 
terior fossa colrtents are prese~ed. 
surviving twin. The ultrasonographer made an impression also demonstrates a complete absence of cerebral hemi- 
of ventriculomegaly. Baby BT's mother subsequently had spheres and an intact falx cerebri. Baby BT's parents were 
the abdominal ultrasound repeated twice, at the 32* and counselled as to the prognosis of the condition and the 
the 33d weeks of pregnancy; these all confinned the minimal risk of recurrence in subsequent pregnancies. She 
presence of abnormal intramanid structures. She was there- was followed up at the high-risk neonatology clinic and 
fore delivered by elective Caesarean section at 34 weeks was last seen at the age of 3 months. Evaluation at that 
of gestation. BT, twin 1, had a birth weight of 2.15kg and time revealed generalised spasticity, signs of visual 
Apgar scores of 7 and 10 at 1 and 5 minutes respectively. impairment and failure to attain any of the developmental 
The second twin was a macerated still birth, which weighed milestones expected for her age. Her occipito-frontal 
~ g m m s .  circumferencew as however within normal limits for age. 
On examination, BT was found to be a preterm female 
neonate, pink in room air, with an axillary temperature of Discussion 
36.5"C. Her facial features were normal. Neurological Hydranencephaly is a rare malformation of the brain. 
examination revealed a conscious, active neonate, occip- This condition is associated with a poor prognosis and 
itofrontal circumference was 32.5cm, (within normal limits) most of the affected children do not survive beyond the 
and the anterior fontanelle was normotensive. The primi- first year of life.'.14 A few cases of prolonged survival 
tive reflexes: sucking and grasp reflexes were present and beyond the first year of life have been rep~rted.'~H.'~ow - 
normal. Her pupils were equal and bilaterally reactive to ever, prolonged survival in these cases has not been asso- 
light and muscle tone was normal in all limbs. Examination ciated with an improvement ia respon8iveness or aware- 
of the other systems revealed no abnormalities. ness of silf and envir~nment.'~.'~ 
A transfontanelle ultrasound scan of the brain was Loss of cerebral tissues supplied by the anterior 
carried out on the fo& day of life but the findings were circulation, that is, the internal carotid arteries, with 
inconclusive and a computerised tomography (CT) scan preservation of the tissues supplied by the posterior 
of the brain was thus suggested for further evaluation. circulation represents the hallmark of hydranencephaly. 
This was done on the lomd ay of life and findings were The thalami receive their blood supply from the posterior 
consistent with a diagnosis of hydranencephaly. Figure 1 circulation perforating vessels, and are therefore preserved 
is an axial CT scan of the brain showing a complete ab- in cases of hy~lranencephaly.~" 
sepce of the cerebral hemispheres, their replacement by Thromboplasticm aterial from a deceased co-twin has 
fluid and preservation of the posterior fossa structures, all also been described as a cause of hydranencephaly in the 
in keeping with a diagnosis of hydranencephaly. Figure 2 surviving twin.l1J2H ann et al" reported hydranencephaly 
WAlM VOL. 25 NO 3, JULY - SEFDMBER 2006 
UNIVERSITY OF IBADAN LIBRARY
Intrauterine fetal death of one of twins, coexisting with hydranencephaly in the surviving co-twin: A case report - JA. Obwu et a1 
in a surviving twin following intrauterine fetal demise of 
the co-twin, while Larroche et all2r eported classical cases 3. Dixon A. Hydranencephaly. Radiography. 1988; 54: 12-13. 
of intracranial malformations in surviving twins coexisting 
with maceration of the co-twin in 7 sets of monozygotic 4. Csabay L, Szabo I, Papp C et al. Central Nervous System 
twins. Although the pathogenesis of hydranencephaly in anomalies. Ann N Y Acad Sci 1998; 847: 21-45. 
these cases is not fully understood, it is believed that trans- 5. Halsey J. Hydranencephaly. In: Vinken P, Bruyn G, Klawans 
placental transfer of thromboplastic material from the dead H Eds. Handbook of Clinical Neurology. Amsterdam: 
to the living fetus plays a major In the report Elsevier Science, 1987: 337-53. 
presented, an initial abdominal ultrasound scan c o d m e d  
twin gestation, with intrauterine fetal death of one of the 6. deLaveaucoupet J, Audibert F, Guis F et al. Fetal Magnetic 
twins at 23 weeks of gestation. Intracranial structures in Resonance Imaging of Ischaemic Brain Injury. Prenat Diag 
the surviving twin were however normal at that time. A 2001; 21: 729-36. 
repeat abdominal ultrasound scan 8 weeks later revealed a 
major abnormality, initially considered to hydrocepha- 7. Myers R. Brain Pathology Following Fetal Vascular Occlu- be sion: an experimental study. Invest Ophthal 1969;8:41. 
lus in the surviving twin. Further evaluation with a cranial 
CT scan however revealed a definitive diagnosis of 
8. StevensonD A, Hart EL, Clericuzio CL. Hydranencephaly 
hydranen-cephaly. This finding is consistent with pre- in an infant with vascularmal-formations. Am J Med Genet 
vious observations which suggest liquefaction of previ- 2001; 104: 295-8. 
ously normal brain tissue by thromboplastic material from 
a deceased co-twin as a potential cause of 9. Kubo S, Kishino T, Satake N et al. A neonatal case of 
hydranencephaly. It is therefore probable that the intrau- hydrawcephaly caused by atheromatous plaque obstruc- 
terine fetal death of the second twin resulted in tion of aortic arch: possible association with congenital 
hydranencephaly in Baby BT. Cytomegalovirus infection? J Perinatoll994; 14: 483-6. 
In the case presented, the availability of CT scan in 
this case facilitated the definitive diagnosis of 10. Laure-KamionowskaM , Dambska M. Damage of maturing 
hydranencephaly. The head size may be normal, increased brain in the course of Toxoplasmic encephalitis. 
or even smaller than the expected in infants with Neuropathol Pol 1992; 30: 307-14. 
hydranencephaly. Cases of hydranencephaly with in- 
creased head size can be readily misdiagnosed as hydro- 11. Hann JS, Lewis AJ, Barnes P. Hydranencephaly owing to 
twin to twin transfusions: serial fetal ultrasonography and 
cephalus.I6 However, the absence of a circumferential rim magnetic resonance imaging fmdings. J Child Neurol2003; 
of cerebral tissue helps to differentiate hydranence-phaly 
from hydrocephalus. 
Intrauterine fetal death has been known to be associ- 12. Larroche JC, D r ~ d lPe,  Delezoide AL et al. Brain damage 
ated with complications like sepsis, coagulopathy and sec- in monozygous twins. Biol Neonate 1990; 57: 261-78. 
ondary infertility in the mother. This report, like previous 
ones, suggests the development of hydranence-phaly in 13. To W, Tang MH. The association between maternal 
the surviving fetus in cases of multiple gestation as an- smoking and fetal hydranencephaly. J Obstet Gynaecol 
other major complication. Res 1999; 25: 39-42. 
References 14. Covington C, Taylor H, Gill C et al. Prolonged survival in 
1. William DeMyer. Normal and abnormal development of hydranencephaly: a case report. Tenn Med 2003; 96: 423-4. 
the neuraxis. In: Rudolph CD, Rudolph AM, Hostetter 15. Mc Abee GN, Chan A, Erde EL. Prolonged survival with 
MK, Lister G, Siege1 NJ eds. Rudolph's Paediatrics. New hydranencephaly : report of two patients and literature 
York: McGraw Hill, 2003; 2178. review. Paediatx Neurol2000; 23: 80-4. 
2. Byers BD, Barth WH, Stewart TL, Pierce BT. Ultrasound 16. Adeloye A. Hydranencephaly in Malawian Children. East 
and MRI appearance and evolution of hydranencephaly in Afr Med J 2000; 77: 316-8. 
ukro: a case report. J Reprod Med 2005; 50: 53-6. 
WAJM VOL. 25 NO 3, JULY - SEFIEIVB2~00 6 
UNIVERSITY OF IBADAN LIBRARY