Crouzon disease is a genetic syndrome characterized by premature obliteration and ossification of two or more sutures of the skull [most often the saggital and coronal sutures], exophthalmoses and mid-facial hypoplasia, resulting in a craniofacial dysostosis. It is often called a craniostenosis. (Mary, Kugler) The type of stenosis is determined by the sutures which are obliterated. Types include scaphocephaly in which the head looks like a boat, oxycephaly in which the top of the head is pointed, wedge-shaped skull and oblique types have been documented in literature. (Lukasz, Mutusiak)
Crouzon's disease is a rare disease that affects 1 in 25000 live births worldwide and about 16.5 per 100000 live births in the United States. It affects individuals of all ethnic or racial backgrounds. Crouzon syndrome is a genetic disorder caused by a mutation on chromosome 10, being transmitted as an autosomal dominant condition, or as a mutation. This can either be a spontaneous mutation which appears in the offspring, or an inherited mutation on the chromosome. Most patients with Crouzon syndrome possess mutations in the extracellular immunoglobulin III domain of the fibroblast Growth Receptors 2 (FGFR2) gene.
Differential diagnosis of Crouzon syndrome includes Apert syndrome, Jackson-Weiss, Carpenter, Pfeiffer and Saethre-Chotzen syndrome. The major distinguishing feature between these other diseases and Crouzon's syndrome is the absence of limb abnormalities in Crouzon’s'. (Lukasz, Mutusiak)
The history is that of observed deformity from birth together with other characteristics of the disease. Patient can also present with headache and convulsions. Clinical features include synostosis, hypertelorism, short upper lip, mandibular prognathism and hypoplastic maxilla. (Mary, Kugler)
Ocular manifestations of the syndrome include divergent strabismus, papilloedema, widely spaced eyes, conjunctivitis, keratitis, poor visual acuity and optic atrophy; other rare abnormalities include nystagmus, iris coloboma, anisocoria, aniridia, microcornea, megalocornea, cataract, ectopia lentis, blue sclera, luxation of the eye and glaucoma. All these ocular symptoms arise as a result of structural abnormalities beginning from the embryological origin of the tissue of the craniofacial region. Malformations of the messenchyme and ectodernal tissue later result in these symptoms. From the aforementioned, it can be deduced that just about any ocular manifestation may as part of the Crouzon’s Syndrome.
Imaging studies are important to clinch a diagnosis. Skull radiography can show the characteristic obliterated suture lines, shallow eye sockets [presenting as exoptalmos] and other cranial abnormalities that may have arisen. Radiography of the spine also shows abnormalities.
A full ophthalmologic examination is required to determine the extent of ocular involvement in the disease. Genetic testing is also done to find out if there is a chromosomal abnormality in the chromosomes. (Mary, Kugler)
If the patient presents with intracranial hypertension, there is need to perform neurosurgical procedures to relieve the pressure. This would go a long way in preventing further visual loss from optic atrophy. The surgery may be undertaken in stages because it is a difficult one. Also, facial reconstruction surgery can also be carried out on the patient to treat the facial abnormalities. (Lukasz, Mutusiak)
It is important to manage Crouzon's syndrome as early as possible as more complications arise as the patient grows up. Such complications like mental retardation, airway obstruction and decreased visual acuity, and even outright blindness can all be prevented if treatment is initiated early in life. With the proper treatment, patients with Crouzon's syndrome can also live productive lives and live as active members of the main stream society.
References
Lukasz, Mutusiak. "Crouzon Syndrome". Medscape Refernce: Drug, disease and procedures. August 13, 2010. http://emedicine.medscape.com/article/1117749-overview#showall
Mary, Kugler. "Crouzon Syndrome". About.com Rare Diseases. January 18, 2004.
G Pournima, Y Monica & S Meghna. "Crouzon Syndrome: A Case Report". Eurpoean Journal of Dentistry and Medicine.
