Outlook for the Child With a Cephalocele

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Outlook

for the

Child

With

a Cephalocele

Mark S. Brown, MD, and Margaret Sheridan-Pereira, FRCPI, DObst DCH, DStats

ABSTRACT. Specific information on the outcome for a

child with a cephalocele can be difficult to find and

interpret. To update outcome information for the child

with a cephalocele, the investigators compared outcome

of 34 infants from their institution with that of those in

previously published series. For the infants from the

investigators’ institution, overall mortality was 29% and

was confined to infants with posterior defects, which was

consistent with other published series. Additional major

congenital abnormalities were present in nearly half the

infants, and these were an important factor in

contrib-uting to a poorer prognosis as well as whether the defect

could be operatively reduced. Seizures and

hydrocepha-lus were often secondary problems in those infants who

did worse. In addressing outlook for the infant with the

cephalocele, primary factors to be considered are

opera-bility and the presence of additional major abnormalities,

both mtracranialand extracranial. Pediatrics

1992;90:914-919; cephalocele, meningocele, encephalocele.

A cephalocele is a congenital prolapse of central nervous system elements, including meninges (men-imgocele) and often brain tissue (encephalocele), through a skull defect.’ Cephaloceles, also termed cranium bifidum, most often occur along the midline of the skull from the anterior to the posterior cranium

and are grouped within the developmental category

of neural tube defects, which also include spina bifida and amemcephaly.

Surgical repair of cephaloceles was first attempted more than 100 years ago, and in 1943 Ingraham and Swan5 reported the first large series of 84 cases of cephalocele, 63 of which were posterior. Posterior defects had a worse prognosis, attributed to hydro-cephalus. With the introduction of ventricular shunt-ing, mortality with cephaloceles decreased to about

45%67 and in the series reported by Lorber7 in 1967

of 55 infants with cephaloceles, the single most im-portant prognostic factor was whether there was brain tissue in the cephalocele sac. Microcephaly was com-mon and associated with both severe mental

retar-dation and physical handicaps. A later report by

Lorber and Schofield8 in 1979 included 347 infants with posterior defects treated between 1954 and 1977, with a similar mortality of 47%; of the 78 surviving infants, only 4% (n = 2) of those with encephaloceles

were normal compared with 48% (n 14) with

From the Department of Perinatology, Children’s Hospital, and Department of Pediatrics, University of Colorado Health Sciences Center, Denver. Received for publication Apr 8, 1992; accepted Jun 1 7, 1992.

Reprint requests to (M.S.B.) P/SL Medical Center, 1719 E 19th Ave. Denver, CO 80218.

meningoceles. In this large series, outlook was worse when there was brain tissue in the sac, microcephaly, or a larger defect.

The only series of anterior defects with detailed

follow-up was by Suwanwela and Hongsprabhas9 in

1966. Mortality was only 12%, and 57% of those

examined (n = 14) were normal. Mealey et al’#{176}and

Simpson et a!2 have reported children with anterior

cephaloceles in combined series, with similar findings of a better outlook for anterior defects.

The aim of the current report was to obtain as specific information as possible on prognostic factors for the child with a cephalocele through review of our institution’s experience and that available in the literature. The outlook for the child with a cephalocele primarily depended on whether the defect could be reduced and the impact of additional major abnor-malities.

METHODS

All admissions to The Children’s Hospital in Denver between January 1, 1940, and December 31, 1987, were reviewed, and a total of 34 infants with a cephalocele were identified. Information obtained from the hospital records included maternal history, sex, location and size of the defect, brain tissue involvement, additional abnormalities, surgical treatments, mortality, morbidity, and fol-low-up information. The classification of defects and outcome used was similar to that used by others.23’#{176} Both meningoceles and encephaloceles were included. An encephalocele included any

de-fect that had radiographic or ultrasound imaging showing brain

tissue or had brain resected during surgery. Anterior cephaloceles

were sited at some point between the bregma and the margin of

the ethmoid bone. Posterior cephaloceles were defined as panetal when the defect was between the bregma and the lambda, and

occipital when the defect arose between the lambda and the

foramen magnum, possibly including one or more of the cervical

vertebrae. Size was taken as the greatest measured dimension. One

child had primary surgery done elsewhere and had been admitted for revision. His follow-up information was included.

For follow-up information, contact was made with the parent(s) and primary and specialty physicians. Because of the diversity of information sources, developmental handicaps were categorized into mental, motor, and sensory disabilities for simplicity. When these were present they were graded as either mild or severe, depending on their impact on the child’s functional capacity.

Statistical comparison was by x2.

RESULTS

There were 22 posterior defects (five meningoceles) and 12 anterior defects (eight meningoceles) (Fig 1). Acranium was classified as a posterior defect. There were no cases of basal (nonvisible) anterior cephalo-celes. Five of the anterior defects presented in the midline, and 20 of the posterior cephaloceles were in

the midline. Defects varied in size from 1 cm to 30

cm. The child with the largest defect, which only

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Fig 1. Distribution of cephaloceles separated into meningoceles (unshaded) and encephaloceles (shaded).

Defects

Posterior

Defects

outcome with only a mild fine motor handicap. There were 1 7 boys and 1 7 girls. The sex distribution ac-cording to the site of the defect was not significantly different; 9 boys and 13 girls had posterior defects, and 8 boys and 4 girls had anterior defects (P = .23).

Maternal history included a mean age 25.7 years and 4 multigravid mothers, 2 of whom had had previous perinatal losses (an unexplained stillborn and an anencephalic infant); 10 had a history of spontaneous abortion; 2 had insulin-dependent diabetes; and 1 mother reported having a cephalocele herself at birth, although these records were not reviewed.

Additional major abnormalities were present in 15 (44%) of 34 infants (Table 1), 7 (58%) with anterior

defects and 8 (36%) with posterior defects. Those

with anterior defects more often had abnormalities of or within the cranium, while those with posterior defects more often had abnormalities in extracranial

sites. Only 3 of the 22 posterior defects (and none of

the anterior ones) were considered inoperable. These 3 infants died by 6 months of age. Follow-up infor-mation was available for 28 (82%) of the cases (Fig 2). Age at follow-up was from 1 to 13 years; the 6 without any follow-up were born before 1964 and the families could not be located. For those infants born after 1964, follow-up information was available. The factors that were primarily associated with poorer outcome were posterior location, presence of other major congenital abnormalities, and inoperability.

Mortality was 29% (10/34) and confined to infants with posterior cephaloceles. These deaths (n) were

attributed to complex congenital heart disease (3),

defect mnoperability (3), acranium (1), acute brain herniatiom due to a blocked shunt in a child with mild motor defect (1), and infection in a child with severe handicaps (1); a child with meningomyelocele and severe delays died after the 1 7th hospital admission at 2 years of age (1). Developmental outcome was not associated with either the size of the defect, which ranged from 1 to 30 cm, or the presence or absence of brain tissue in operable defects. In the children

TABLE 1. Additional Major Congenital Abnormalities and Outcome According to Site of Cephalocele

Abnormality Outcome’

craniosynostosis

Myelomeningocele, NF

hydrocephalus

Hydrocephalus Severe developmental delay (8 y) Agenesis of corpus callosum, Severe developmental

anophthalmia, multiple fa- delay (10 y)

cial abnormalities

Porencephaly, anophthalmia, Severe developmental

multiple abnormalities delay (7 y)

Facial clefts, dermoid of corpus Normal (4 y)

callosum

Facial clefts, coloboma Normal (2 y)

Posterior

Complex congenital heart din- Died by 6 mo

ease, hydronephrosis

Complex congenital heart dis- Died at 14 mo

ease, visceral heterotaxia

Complex congenital heart dis- Died at 4 mo

ease, cleft lip/palate, micro-phthalmia

Arhinocephaly, cerebellar Inoperable, died agenesis, hydrocephalus,

pituitary agenesis, adrenal hypoplasia

Myelomeningocele Died at 2 y

Hydrocephalus

()t

2, mild (2 y, 7 y); 1, severe (2 y); developmental delays

Klippel-Feil, hydrocephalus Severe developmental delays (1 y)

Acranium Died at 4 d

0 NF, no follow-up; age at follow-up is given in parentheses.

t(n).

Fig 2. Pie graphs of the outcome of cephaloceles according to their

distribution between anterior and posterior sites.

with anterior defects, severe handicaps were present

in 4 (33%), and mild in 2 (17%) (Table 2). The

presence of other intracranial abnormalities in 2 in-fants with anterior cephaloceles, with or without fa-cial clefting, was associated with severe handicaps. In the surviving children with posterior defects, severe

handicaps were present in 2 (33%), and mild in 3

(50%). Microcephaly was noted in 7 of the children, all with posterior defects; 2 had no follow-up infor-mation, 3 died (all of whom were inoperable), 1 had severe handicaps, and the remaining 1 was normal.

Nine children had hydrocephalus diagnosed and a

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TABLE 2. Outcome According to Site of the Cephalocele’

Location Died Severe Handicap Mild Handicap Normal No Follow-up

Meningocele (n = 8)

...

1, Severe mental and motor (8 y) 2, Severe mental,

motor, and visual (13 y, 7 y)

1, Mild motor; 1, mild visual (12 y)

3, Normal (2 y, 3 y, 4 y)

2, Normal (2 y, 3 y)

..

2

Posterior

Encephalocele (n = 17) 9 1, Severe mental,

motor, and blind

(1 y)

1, Mild fine motor and strabismus

(7 y); 1, mild

memory deficit (lOy)

2, Normal (4#{189}y,

5 y)

3

Meningocele (n = 5) 1 (No repair due to heart defect)

1, Severe mental and motor (4’/2 y)

1, Mild perceptual and fine motor (5

y)

1, Normal (5 y) 1

Totals (n = 34) 10 5 5 8 6

0 Age at follow-up is given in parentheses.

posterior ones. One of these died, 5 had severe hand-icaps, 1 had mild delays, 1 was normal, and 1 had no follow-up information. Seizures were recorded in 14 children, 5 with anterior defects and 9 with posterior defects; of these, 5 died, 5 had severe handicaps, 1 had mild handicaps, 1 was normal, and 2 were unable to be followed up.

DISCUSSION

The outlook for the child with a cephalocele pri-manly depended on site, operability, and additional major abnormalities. Overall mortality was 29%, but confined to those with posterior defects and associ-ated with inoperability, congenital heart disease, in-fection, and shunt malfunction. Microcephaly, sei-zures, and hydrocephalus occurred in almost half of the infants, and when present, were secondarily as-sociated with a worse outcome. The association of congenital abnormalities was different between the posterior and anterior defects, but with either, addi-tional major abnormalities were an important consid-eration in determining the infant’s prognosis. This information represents an expanded view of the out-look for the child with a cephalocele.

Although the frequency of cephaloceles has ranged

from 1 per 240011 to 1 per 12 500 live births,’2 most

estimates have been between 1 per 5000 and 1 per

9000.1321 Prevalence more aptly applies to the re-ported frequency of cephaloceles because the true incidence is hidden in stillborns, underreferral of

mas-sive defects, and early pregnancy losses. This latter

has been estimated to be from 7%22 to 20%’ of all cephalocele defects. Since our series is from a regional referral center, it is likely that this misrepresents the

true

population prevalence, because not all infants may have been referred, especially those with ob-viously inoperable defects, which are more often pos-terior. There is considerable geographic variation in the proportions of anterior23and posterior’5.’#{176}’7’31M cephaloceles, although overall prevalence is about the

same.19’203’ Posterior defects were 65% of our series,

which falls into the range of reports from the Western hemisphere.

Meningoceles comprised 38% of our defects, a

fig-ure similar to the 37% in the combined series of

Simpson et al.2 Meningoceles included 67% and 29%

of anterior and posterior defects, respectively, in our

infants. In series of posterior defects, meningoceles

include 18% to 49% of the defects,6’7 while in those

series of anterior defects this distinction has not been

made.

The sex distribution of anterior defects varies widely, from 40%9b0 to 73% females.27’35 In our series, females were 33% of those with anterior defects. The sex distribution of infants with posterior defects has ranged from 5#{216}%68lo.18 to

75%

females.’2 In our

series, 62% of the posterior defects were in females. A female predominance in livebirths with cephalo-celes has been speculated to be due to an inordinately

high early prenatal loss of male fetuses with

cepha-loceles,36 although from the considerable variation in

sex distribution in the above reports this does not seem to always hold true.

The site of the inner bony defect in the skull of

anterior cephaloceles has been localized to the region

of the foramen cecum.3’26’31’37’38 The facial component of the defect determines the subclassification.38 The most common anterior defect was the nasofrontal cephalocele, which presents at the glabella and whose external opening is between the frontal and nasal bones.3’23’29 The site of posterior defects is most often

along the median plane, as were 9 1

%

of those in our

series. The level varies and similarly determines the subclassification. When the defect is between the parietal bones, the defect is called parietal; when it is at or around the occipital prominence it is termed occipital, suboccipital when it occurs below this, and occipitocervical when it extends into the cervical re-gion.39 The association of Klippel-Feil deformity with

posterior cephaloceles and the similarity between

in-iencephaly and Klippel-Feil syndrome suggests that cephaloceles are related to iniencephaly and spina bifida.4 Posterior defects located below the occipital

prominence may extend into the cervical region and

are frequently associated with other intracranial ab-normalities of the posterior fossa. When defects in-volve the occipital protuberance, a venous sinus

usu-ally runs in the neck of the sac.27 Large occipital

defects may extend both above and below the

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por-tions of cerebrum and cerebellum with absence of the

tentorium.3 These factors not only make surgery

dif-ficult or impossible as in three of our cases, but ma also affect both long-term morbidity and mortality.2

The etiology of the cephalocele defect is unclear.

Environmental and genetic factors have been

exam-med and both seem to play a role.”9”2’20’2225’35’4#{176} Other etiologic considerations have arisen from ani-mal studies in which cephaloceles have been pro-duced by folic acid antagonists, trypan blue, vitamin A excess, malnutrition, and x-irradiation.28 A recent

double-blind trial of preconception folic acid

supple-mentation in women with a previous child with a

neural tube defect demonstrated a significant

reduc-tion in neural tube defects, although cephalocele was

not reported separately.4’

The cephalocele abnormality occurs between 25

and 50 days for anterior defects and up to 60 days for posterior ones.4’42 The association of cephaloceles with an abnormality in heart development, which is

occurring at the same time, suggests that the two

occurring together may represent a field defect. Other

major congenital abnormalities, both intracranial and extracranial, were present in 44% of our infants,

which is within the range of previous reports.3’8’20’43

Cohen and Lemire44 reviewed more than 20

syn-dromes associated with cephaloceles, which in our series included amniotic band syndrome, absent

cor-pus callosum, facial clefting, Klippel-Feil, and

men-ingomyelocele.4548 Cephaloceles associated with the amniotic band syndrome are clearly a separate etio-logic sequence and the facial clefts are characteristi-cally multiple and asymmetric.47 Three of the children with anterior defects in our series had significant

facial clefting characteristic of the amniotic band

syn-drome including involvement of the eyes.

Associated abnormalities with anterior defects are more often limited to the cranium.9’31 In our series these included cleft lip and palate, porencephaly,

anophthalmia, facial hypoplasia, agenesis of corpus

callosum, and dermoid of corpus callosum.

Micro-cephaly occurred in 7% to 24% of the infants in

Suwanwela and Hongsprabhas’ series,9 although we did not find any record of microcephaly in those with

anterior defects. This may have been due to the

smaller number of children with anterior defects in

our series, differences in measurement of head cir-cumference, or a different association of other abnor-malities in populations with a higher prevalence of anterior defects. From 12% to 24% of infants with

anterior defects have had hydrocephalus,9’3’ which is

consistent with the 1 7% in our series. Significant eye

abnormalities occurred in 25% of those with anterior

defects, in accord with other reports.9’28 Defects in brain development have been reported to occur in 3% to 23% of infants with anterior defects,9’24’26’28

al-though intracranial abnormalities have not been

rou-tinely assessed in any series. We found 25% of our infants with anterior defects had some identified

ab-normality of the brain. In an autopsy series of 12

children with anterior defects, Suwanwela and

Suwanwela37 reported brain abnormalities of

holo-telencephaly, abnormal gyri, hydrocephalus, small frontal lobe, and elongated brain stem.

In the infants with posterior defects in our series, other major congenital abnormalities occurred in 25%. We found one infant with Klippel-Feil

syn-drome, the most frequently identified condition

as-sociated with posterior cephaloceles.43 There were two infants with myelomeningoceles in our series, one with an anterior and the other with a posterior defect. On occasion, cephaloceles have been observed within families also affected with spina bifida, hydro-cephalus, or other central nervous system

anoma-lies.3’8 However, the infrequent association between

cephaloceles and neural tube defects in most series

would suggest that these two entities are not closely

related.7’8 In those with posterior defects, congenital

abnormalities were more likely to be extracranial and

included congenital heart disease, limb abnormalities,

hydronephrosis, visceral heterotaxia, asplenia, and

myelomeningocele. In the literature, associated

ab-normalities have included congenital heart disease, limb abnormalities, hydrocephalus, microcephaly, cleft lip and palate, and tracheoesophageal fistula. Hydrocephalus was present in 18% of our infants with posterior defects. Hydrocephalus has been re-ported to occur with posterior cephalocele in 16% to 5 1 % of patients, without distinction between

menin-gocele and encephalocele.26’8’#{176}’33 The association of

cephalocele with other congenital abnormalities,

ex-cluding hydrocephalus and microcephaly, ranges

from 1 7% to 61

%,

often including both minor and

major abnormalities grouped together.8’41’43 These

es-timates are probably underestimates, inasmuch as

evaluations have not been systematic and those in-fants deemed inoperable have died early and were often excluded.

Outcome

Outcome for the child with an anterior defect has been universally better than for those with a posterior defect.33 Survival with anterior defects has been

re-ported from 80% to 93%#{149}9.b0.24.29 Those with posterior

cephaloceles in our series had a 55% survival, com-parable with the 40% to 75% survival reported in

other series.2’7’8”0 In our series, mortality was most

often due to the impact of other abnormalities or the

inability to safely repair the defect. All babies with lesions deemed inoperable died within 6 months. Meningoceles have had a much lower mortality-25% in our infants with posterior defects and 10% in Lorber and Schofield’s 1979 series.8

Disabilities in children surviving with anterior cephaloceles have been more frequent in those with encephaloceles, although this was not our experience, which may have been due to our smaller numbers or a different definition of encephalocele. The primary

morbidity in children with anterior defects has been

facial disfigurement, anosmia, and visual prob-lems.9”#{176}Although there were no deaths in our infants

with anterior defects, significant long-term disability

was present in 50% of those who had follow-up and was associated with severe facial clefting, intracranial abnormalities, and significant visual impairments. Factors that did not seem to influence outcome in-cluded sex, presence of brain tissue in the defect, and

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without brain tissue, the important factor in deter-mining outcome was the presence of other intracra-nial abnormalities.

In infants with posterior defects, handicaps have been related to brain abnormalities, growth retarda-tion, Klippel-Feil deformity, ataxia, blindness,

hydro-cephalus, fine motor coordination, and seizures.4

Se-vere long-term disabilities occurred in 25% and mild handicaps in 38% of the surviving infants with

fol-low-up in our series, regardless of the presence or

absence of brain tissue or size of the defect when

operable. This is possibly explained by the anatomy of the remaining underlying brain, which may be as

important a factor in determining outcome as the

amount of prolapsed tissue. This is supported by 41% of the infants with seizures, of whom 71 % died or had severe handicaps. In other reports, disabilities have ranged from 14% to 73%, the variability de-pending on the extent and details of follow-up.2’7’10

The parietal location of posterior defects is far less

frequent and accounted for 9% of our posterior

de-fects, within the 3% to 27% in the literature.1’3’5”0’32

A series by McLaurin49 made a detailed study of 13 children with parietal encephaloceles. Mortality was 3 1 % and limited to those with brain tissue within the

defect. Follow-up ranged from 9 months to 10 years,

and 5 of the surviving 9 were considered normal.

Seven of the 1 3 had meningoceles, of which 4 were

normal, and none died. In this location,

encephalo-celes rather than meningoceles are associated with

intracranial abnormalities such as agenesis of the

corpus callosum, upward extension of the third

yen-tide, Dandy-Walker c’sts, or porencephalic cysts of the lateral ventricles.3’4

Predictors of Outcome

Although the number of infants seen in our

insti-tution with cephalocele was less than those in other

reports, the distribution of site, sex, mortality, and

outcome was comparable with earlier reports. Those

infants with an anterior defect not associated with

facial clefting or brain abnormalities had good

out-comes. In the infants with posterior defects, poor

outcome was related to other major congenital

ab-normalities, infection, and inoperabiity. In our series

as well as others, hydrocephalus and seizures were a secondary consideration of poor outcome. Inopera-bility is an end of the spectrum of considerations enumerated by Lorber for poor prognosis with

pos-terior cephalocele, which includes the triad of

mi-croencephaly, presence of brain tissue, and large size.7’8 In our series if the defect was able to be safely

closed, then microcephaly, size, and brain tissue

in-volvement did not alone worsen the outlook. This may be due to improvements in diagnostic

evalua-tions, surgical techniques, and postoperative intensive

care. Of interest was that in follow-up in the later

report, 48% of infants with a meningocele were fully

normal compared with only 4% with encephaloceles.8 The infants in our series with posterior encephalocele had the highest mortality but when they survived did not have any worse outcome.

In the report by Simpson et al,2 of 74 patients

treated in Australia between 1955 and 1983, the

prognostic importance of presence of brain tissue and size of herniation was emphasized. These authors

divided the size at 5 cm, with only 8% of those with

smaller lesions doing poorly, compared with 75% of

those with larger lesions. In the series reported by

Mealey et al,’#{176} prognosis depended largely on

whether the lesion contained cerebellum. The size of

lesions ranged from 1 to 14 cm,1#{176}and those children

who were normal in follow-up had a maximum defect

diameter of 7 cm. In our series, size alone was not

associated with poorer outcome since not only did a

number of children with smaller defects do worse,

but some of the larger defects contained only a small

amount of brain tissue. Lesions that have been

deemed inoperable have universally done poorly, with a high mortality.8’10 The posterior defects that were considered inoperable in our series were greater

than 7 cm and contained all brain tissue. Those with

large defects that only partially contained brain were

operable, and these children had a better outcome.

Prenatal Diagnosis

Antenatal screening with maternal serum and

am-niotic fluid a-fetoprotein has not been of much value

because of the closed nature of most cephaloceles.2

Cephaloceles have been diagnosed antenatally by

ultrasound.2’50’5’ In a screening series reported by

Winsor and St John Brown16 from Nova Scotia, none

of the cephalocele defects were missed beyond 16

weeks in the latter part of the study, and for the entire

period from 1980 through 1984, 79% of either spina bifida or cephaloceles were diagnosed antenatally. Anterior defects are less often diagnosed antenatally

because of their lower prevalence in the screened

populations reported, their smaller sizes, and

diffi-culties with technique.52 The differential diagnosis of a cephalocele seen on antenatal ultrasound includes

other central nervous system defects such as dermoid

cyst, hydrocephalus, Dandy-Walker cyst, or a cystic

hygroma of the neck.51 The recommendation of late

termination of pregnancy needs to be with the

exclu-sion of other similar-appearing abnormalities and the

unlikelihood of operability based on posterior

loca-tion, larger size, presence of microcephaly, and

pri-mary inclusion of brain tissue in the sac.5#{176} Summary

In summary, the practitioner caring for an infant

with a cephalocele can use the following to address

the initial care, referral, and counseling of the family.

Associated abnormalities are present in up to 50% of the cases. Mortality depends on cephalocele location, operability, and additional major abnormalities. The presence of brain tissue in the defect does not

neces-sarily

bode a poor prognosis unless the defect is so large that it is considered inoperable. Additional

eval-uation may include computed tomographic scan,

(6)

The option of nonintervention in the care of an infant with a cephalocele can be ethically supported in the infant with microcephaly and a massive defect con-taming all or almost all brain tissue, a condition that is deemed inoperable. In addition, the infant with a larger defect and other significant major congenital abnormalities may have operative risks outweighing surgical benefit.

ACKNOWLEDGMENT

The cooperation of all the parents was deeply appreciated.

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Pediatrics

Mark S. Brown and Margaret Sheridan-Pereira