THE COPPER.html
The copper-beaten skull
N Mahomed, MB BCh, FCRad (D)
T Sewchuran, MB BCh
Z Mahomed, MB BCh
Department of Radiology, University of the Witwatersrand, Johannesburg
Corresponding author: N Mahomed (nasreen.mahomed@wits.ac.za)
Abstract
Variations
and abnormalities of skull appearance and shape are generally related
to a primary maldevelopment of the brain. The copper-beaten skull
appearance is typically associated with craniosynostosis, where
premature fusion of the cranial bone sutures results in the growing
brain exerting pressure on the malleable cranium, producing a pattern
known as the copper-beaten skull appearance.
A 6-year-old girl with known craniosynostosis graphically demonstrates the copper-beaten skull on plain radiography (Fig. 1).
Variations and abnormalities of skull appearance and shape are often related to a primary maldevelopment of the brain.1
The copper-beaten skull appearance is typically associated with
craniosynostosis, which is the premature fusion of the cranial bone
sutures (Fig. 2).2 Severe
craniosynostosis and reduced cranial growth in our patient caused brain
volume to exceed the cranium size, resulting in raised intracranial
pressure.2 Consequently, the
growing brain exerts a continuous pulsatile pressure on the malleable
cranium, producing a gyral pattern evidenced on plain skull X-rays most
commonly known as the copper-beaten skull appearance.3 This is the least common manifestation of craniosynostosis on the developing skull.1
Convolutional markings are inner table indentations that conform to the cerebral surface of the growing brain in infants.1 The
pattern was initially assumed to have resulted from chronically
elevated intracranial pressure but currently it is widely considered to
be a reflection of normal brain growth, without pathological
significance.4 The markings
are most prominent during periods of rapid brain growth, between age 2
- 3 years and 5 - 7 years. They become less prominent after
approximately 8 years of age.1
Diffuse, severe beaten-copper pattern is an
indicator of chronic elevated intracranial pressure, which is more
common in patients with craniosynostosis.4
Additional findings associated with a chronic increase in intracranial
pressure include macrocrania, splitting of the sutures, skull
demineralisation and erosion, or enlargement of the sella turcica.1 The appearance is more frequent in children with complex, rather than simple, craniosynostosis.2
In children <18 months, the presence of a diffuse copper-beaten
pattern on skull radiography, together with narrowing of the basal
cisterns and obliteration of the anterior sulci, increases the
likelihood of raised intracranial pressure.2
,
4
Of interest, Van Der Meulen et al. concluded that the presence of the copper-beaten skull pattern did not significantly affect long-term intelligence levels.2
However, there appeared to be a negative influence on more subtle areas
of development, such as reading, spelling and behaviour.2
These convolutional markings should be
differentiated from Lückenschädel (lacunar skull), which is
due to mesenchymal dysplasia of calvarial ossification. It is
characterised by numerous oval lucencies (a honeycomb appearance about
2 cm in diameter) of the inner table and diploic space.1
,
4
These are usually present at birth and are associated with
meningocoele/myelomeningocoele/encephalocoele, spina bifida, cleft
palate and Arnold Chiari II malformation.1
It is most prominent in the parietal and occipital bones. Occasionally
these findings are normal and disappear by 6 months of age.1
Craniosynostosis is more adequately evaluated for
surgical planning with computer tomography (CT) and 3D reconstructions
(Fig. 3), and has the advantage of concurrently demonstrating the
intracranial complications. The associated interpretation of plain-film
skull radiography is an incidental contribution.
Acknowledgements. We thank Professor S. Andronikou for reviewing this article.
1. Glass BJR, Fernbach SK, Norton KI, Choi SP, Naidich TP. The infant
skull : A vault of information. Radiographics 2004;24:507-522.
1. Glass BJR, Fernbach SK, Norton KI, Choi SP, Naidich TP. The infant
skull : A vault of information. Radiographics 2004;24:507-522.
2. Van der Meulen J, Van der Vlugt J, Okkerse J, Hoffman B. Early
beaten-copper pattern: its long term effect on intelligence quotients
in 95 children with craniosynostosis. J Neurosurgery: Paediatrics
2008;1:25-30.
2. Van der Meulen J, Van der Vlugt J, Okkerse J, Hoffman B. Early
beaten-copper pattern: its long term effect on intelligence quotients
in 95 children with craniosynostosis. J Neurosurgery: Paediatrics
2008;1:25-30.
3. Agrawal D, Steinbok P, Cochrane DD. Significance of beaten copper
appearance on skull radiographs in children with isolated sagittal
synostosis. Childs Nerv Syst 2007;23:1467-1470.
3. Agrawal D, Steinbok P, Cochrane DD. Significance of beaten copper
appearance on skull radiographs in children with isolated sagittal
synostosis. Childs Nerv Syst 2007;23:1467-1470.
4. El Khasab M, Nejat F, Yazdani s, Baradaran N. Aquired
craniomeningocele in an infant with craniosynostosis : a case report.
Journal of Medical Case Reports 2010;4:104-106.
4. El Khasab M, Nejat F, Yazdani s, Baradaran N. Aquired
craniomeningocele in an infant with craniosynostosis : a case report.
Journal of Medical Case Reports 2010;4:104-106.
Fig. 1. PA and lateral skull X-rays demonstrating
impressive convolutional markings (copper-beaten skull appearance) in a
6-year-old girl with known craniosynostosis. Note associated fusion of
the saggital, coronal and lamdoid sutures.
Fig. 2. Axial CT of brain bony windows,
demonstrating the convolutional markings of the inner table of the
skull that conform to the cerebral surface of the growing brain
associated with fusion of the coronal and lamdoid sutures.
Fig. 3. CT 3D saggital reconstruction demonstrating
the prominent convolutional markings of the inner table of the skull.
There is no obvious expansion or erosion of the sellar turcica.