Craniofacial FAQs

What are the advantages of spring assisted surgery?

Spring assisted surgery has advantages in a specific subgroup of patients with craniosynostosis, in particular those with sagittal synostosis.

Advantages:
-The operation is much shorter
-The scar is shorter and less noticeable
-Only a small part of the skull needs to be exposed
-Only a fraction of dura is exposed compared to traditional surgery
-There is very little bleeding
-The need for a blood transfusion is rare
-Recovery and hospital stay is much shorter

Disadvantages:
The new skull shape take several weeks to develop
The springs must be removed about 4-6 months later. This is a minor procedure.
The springs can be felt beneath the scalp whilst they are present

There is excellent long term data available now confirming the safety and efficacy of spring surgery. These can be provided to referring medical professionals on request. Some of these are listed under publications.

Is surgery necessary for single suture craniosynostosis?

Rationale for surgery in ‘isolated’ single suture craniosynostosis

For many years a significant body of international opinion has believed that the prime reason for operating in cases of single suture craniosynostosis is for cosmetic reasons. Quite recently it is becoming increasingly accepted that the risk of raised intracranial pressure and the possibility of significant psychological sequelae are higher than previously thought in these children. 1,2

Intracranial pressure (ICP)

The brain grows rapidly after birth and by the first year of age it is approximately 80% of adult size. The cranial sutures are designed to allow rapid skull expansion as the brain expands. If a suture fuses prematurely, rapid brain growth still occurs but will push out in another direction causing an external skull deformity. If the brain requires a higher tissue tension to displace the adjacent bones then there will be a higher pressure within the cranial cavity and within the brain tissue. Consequences of raised ICP may include mental delay and blindness.

Incidence of raised ICP in single suture craniosynostosis.

Raised ICP is seen in at least half of all cases with multiple suture synostosis. In single suture synostosis the rate is lower.

The London group showed 24% (of 83 cases) had raised intracranial pressure.3 The rate was 17% (of 18 cases) of scaphocephaly. 4

The Paris group showed 14% (of 75 cases) had definitely raised intracranial pressure. However a further 62% were borderline with pressure higher than expected but not in the range that is definitely raised. 5

The above studies contained a large number of children and used intracranial ICP monitors. More sensitive is the use of SPECT scanning, not readily available in this country. It has recently been shown that abnormalities in brain blood flow were present adjacent to the site of a single fused suture in 71% of cases and that these brain perfusion defects were corrected after early reconstructive surgery. The numbers in the study were small (7 cases). The authors recommended early surgical intervention to prevent brain compromise secondary to abnormal blood flow. 6

A study of 10 children with single-suture craniosynostosis showed that cerebral glucose metabolism (a measure of local brain function) was lower than normal in the posterior occipital cortex. It consistently increased after cranial remodeling. 7

Methods of detecting raised ICP

Currently the only accurate method for determining raised intracranial pressure is an intracranial pressure monitor. It is well recognized that ICP varies throughout the day, being highest during REM (rapid eye movement) sleep, and so ideally monitoring should be performed overnight for a minimum of 12 hours. This is unnecessary for children with craniosynostosis who undergo early surgery unless there is a later concern about raised ICP.

Radiological tests (such as xrays and CT scans) may sometimes show the effects of raised ICP such as a “copper beaten” skull, erosion of the dorsum sella, widened sutures and narrowing of the basal cisterns. However the sensitivity of radiology for detecting raised ICP is very low and it is not recommended to screen for raised ICP in children with craniosynostosis.8,9

Symptoms sometimes seen with raised ICP include vomiting and headaches. However in most cases the effects are chronic and subtle with no readily identifiable symptoms. Headache, the most classic symptom of raised ICP, is often not able to be vocalized in young children and the presence of headache in cases of proven raised ICP is inconsistent. Symptoms are more obvious in older children. The Philadelphia group reported 16 patients with scaphocephaly who had delayed treatment (average age 3.2 years). 25% had obvious symptoms of raised ICP. 10

Blindness with raised ICP

Blindness is a devastating consequence of craniosynostosis and it is a well recognized problem in complex craniosynostosis where its onset may be rapid and with little warning.10 Cases of blindness in single-suture craniosynostosis are uncommon with a few isolated case reports.11 I saw one case when I worked at the Scandinavian craniofacial unit in Sweden in a 4 year old girl with untreated scaphocephaly.

Blindness is uncommon because it tends to develop in later years and most cases of single-suture synostosis have a cranial decompression procedure performed during the first year of life. It is more common with cases who have minimal cranial involvement that go unnoticed until late childhood.12,13 Of 290 children treated for craniosynostosis at Birmingham, 9 (3%) had visual failure at presentation as the result of raised ICP.12 In 7 children this was the late presenting symptom of an undiagnosed deformity. 3 of the 9 children had a single-suture synostosis.

Raised intracranial pressure (ICP) is known to cause papilloedema (oedema of the optic disc) and if prolonged, optic atrophy. Its presence in the younger child reliably indicates raised ICP however chronic and gradual increases in ICP may occur without papilloedema.15 Sustained papilloedema eventually leads to optic atrophy and visual loss. The visual loss tends to be rapid and with little warning. Although visual loss is more likely to occur during the period of rapid brain growth, there are several known cases of sudden visual loss in young adults with craniosynostosis with no warning.16

Mental function with raised ICP

In summary the literature suggests that in single-suture synostosis the rate of raised ICP is s and the incidence of cognitive disability also appears high. Currently it cannot be proven that the raised ICP causes cognitive dysfunction or that surgical intervention alters cognitive outcome. 17

Prolonged elevated ICP is believed to be detrimental to mental function however studies investigating the relationship are complicated by the problem of objective testing particularly in young children.

A critical review of 17 studies investigating the relationship between single-suture synostosis and neurodevelopment demonstrated a three- to five fold increase in the risk for cognitive deficits or learning and language disabilities. There is no difference between the various sutures (metopic, coronal or sagittal) 18

Some of these studies included the following;

The Paris group showed (in 396 cases) that the main predictive factor of mental outcome was the initial developmental level and most patients had a good outcome whether or not they had surgery.19

A Harvard study (16 cases) showed 50% of patients with scaphocephaly had reading or spelling disabilities. 20

In a more recent longitudinal study (84 children with single-suture craniosynostosis) the incidence of mental retardation was two to three times higher than normal. In those children who were not retarded and had reached school age, 47% had learning difficulties. Rates of retardation may increase relative to normal expectations as children mature.21

The London group showed no increased prevalence of global cognitive impairment in scaphocephaly however there was an increased risk of developing speech and language impairment. 22

The Oklahoma group (21 cases of single-suture synostosis) showed 43% were normal, 48% had mild delay and 9% significant delay. 23

While there are pathophysiological mechanisms to explain why brain restriction may affect cognitive development currently there is no conclusive evidence that shows surgery affects the ultimate intellectual outcome. This may be due to limitations of current testing methods. The effect of surgery on preserving mental function in single-suture synostosis is controversial. While some studies have described a possible deterioration in mental function if surgery is not performed, other studies appear to show no increased incidence of developmental delay in the absence of surgery.

Psychological sequelae of abnormal head shapes

There are few studies of large numbers of children who have grown into adulthood with unoperated craniofacial deformities. The incidence of severe psychological distress at some point during adolescence is 35-45% for patients with cleft lip and palate. In a Swiss study of unoperated scaphocephaly patients (30 children who had reached an average age of 9 years), quality of life and psychological adjustment was within the normal range. 24 For many years, the neurosurgical team in Adelaide did not operate in cases of scaphocephaly believing it to be only of cosmetic concern. 25 In the 34 cases studied there was a high incidence of anxiety amongst parents and children. As these patients have subsequently been followed into their 30s they have had 3 times the expected incidence of relationship breakdowns, difficulty maintaining employment and poor self esteem.16

From a practical point of view many occupations and recreational activities require the use of hats, helmets, glasses and protective eyewear. This may be difficult with cranial shapes well outside the normal range.

Modern Craniofacial Surgery

Today craniofacial surgery is a mature discipline with acceptably low rates of serious complications. In the Wellington and Christchurch regions it is undertaken by a well trained team who have spent time in international centres of excellence during their training. We are one of the few centres in the world who currently offer spring assisted skull reshaping to suitable patients, a novel technique associated even lower complication rates.

Families face a difficult decision when choosing whether or not to have surgery for their child with craniosynostosis. Where parents are adamant that they do not want their child to undergo surgery, we may recommend intracranial ICP monitoring to exclude the possibility of raised intracranial pressure.

This information sheet is intended for patients of Mr Charles Davis. It is a summary only and not an exhaustive review of this topic and it is not intended to replace a full discussion about any patients particular situation.

REFERENCES

1 Cohen S, Persing J. Intracranial pressure in single-suture craniosynostosis. Cleft Palate Craniofac. J. 1998; 35: 194-196.

2 T Pittman. Single suture synostosis and intracranial hypertension. J Ky Med Assoc. 2003; 101: 63-70.

3 Thompson DN, Malcolm GP, Jones BM, et al. Intracranial pressure in single-suture craniosynostosis. Pediatr Neurosurg.
1995; 22: 235-240.

4 Thompson DN, Harkness W, Jones B, et al. Subdural intracranial pressure monitoring in craniosynostosis: its role in surgical management. Childs Nerv. Syst. 1995; 11: 269-275.

5 Renier D, Saint-Rose C, Marchac D, et al. Intracranial pressure in craniosynostosis.
J Neurosurg. 1982; 57: 370-377.

6 David LR, Wilson JA, Watson MD, et al. Cerebral perfusion defects secondary to simple craniosynostosis. J. Craniofac. Surg. 1996; 7: 177-185.

7 David LR, Genecov DG, Camastra AA. Positive emission tomography studies confirm the need for early surgical intervention in patients with single-suture craniosynostosis. J Craniofac. Surg. 1999; 10; 38-7.

8 Tuite, G.F., Evanson, J., Chong, et al. The beaten copper cranium: A correlation between intracranial pressure, cranial radiographs, and computed tomographic scans in children with craniosynostosis. Neurosurg. 39: 691, 1996.

9 Eide, P.K. The relationship between intracranial pressure and size of the cerebral ventricles assessed by computed tomography. Acta Neurochir (Wien). 2003; 145: 171-179.

10 Weinzweig et al. Delayed cranial vault reconstruction for Sagittal synostosis in older children. Plast. Reconstr. Surg.
2002; 110: 397-408.

11 Hertle RW, Quinn GE, Minguini N. Visual loss in patients with craniofacial synostosis. J Pediatr Opthalmol Strabismus. 1991; 28: 344-349.

12 Stavrou, P., Sgouros, S., and Willshaw, H.E. Visual failure caused by raised intracranial pressure in craniosynostosis. Childs Nerv. Syst. 1997; 13: 64-67.

13 Martinez-Lage JF, Alamo L, Poza M. Raised intracranial pressure in minimal forms of raniosynostosis. Childs Nerv. Syst. 1999; 15: 11-16.

14 Dollfus H, Vinikoff L, Renier D, et al. Insidious craniosynostosis and chronic papilloedema in childhood. Am J Opthalmol. 1996; 122: 910-911.

15 Tuite, G.F., Chong, W.K., Evanson, J., et al. The effectiveness of papilloedema as an indicator of raised intracranial pressure in children with craniosynostosis. Neurosurg. 1996; 38: 272-278.

16 David, D. Australian Craniofacial Unit. Personal communication.

17 Lekovic GP et al. Cognitive outcome of craniosynostosis. Semin. Pediatr. Neurol. 2004; 11: 305-10.

18 Speltz ML et al. Single-suture synostosis: a review of neurobehavioral research and theory. J. Pediatr. Psychol. 2004; 29: 651-68.

19 Arnaud E, Renier D, Marchac D. Prognosis for mental function in scaphocephaly. J Neurosurg. 1995; 83: 476-479.

20 Magge SN et al. Long-term neuropsychological effects of sagittal craniosynostosis on childs development. J. Craniofac. Surg. 2002; 13: 99-104.

21 Kapp-Simon KA. Mental development and learning disorders in children with single suture craniosynostosis. Cleft Palate Craniofac. J. 1998; 35: 197-203.

22 Shipster, C., Hearst, D., Somerville, A., et al. Speech, language and cognitive development in children with isolated sagittal synostosis. Dev Med Child Neurol. 2003; 45: 34-43.

23 Panchal et al. Neurodevelopment in children with single-suture synostosis and plagiocephaly without synostosis. Plast.Reconstr. Surg. 2001; 108: 1492-8.

24 Bolthauser et al. Sagittal craniosynostosis: cognitive development, behaviour, and quality of life in unoperated children. Neuropediatrics. 2003; 34: 293-300.

25 Barrit J, Brooksbank M, Simpson D. Scaphocephaly: aesthetic and psychosocial considerations. Dev. Med. Child Neurol. 1981; 23:183-91.

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