Von Recklinghausen’s disease, or neurofibromatosis (NF), is characterized by multiple neurofibromas (tumors that arise from Schwann cells and fibroblast of the neurilemmal sheath of the peripheral nerve), pigmentations in the epidermis (i.e., the café au lait spots that are smooth-edged cream-brown cutaneous macules) and the iris ( i.e., the Lisch nodules, which are melanocytic hamartomas), and pachydermatoceles of the skin. The disorder may be associated with tumors of the central nervous system (such as optic nerve glioma and meningioma) and a mild degree of mental retardation, related presumably to developmental abnormalities of the celebral cortex. Seizure are also common.
Associated anomalies of the skeletal and cardiovascular systems have been reported. Because of its characteristics, NF has been grouped with neurocutaneous syndromes or phakomatoses (from Greek phacos meaning “freckle”), disorders in which abnormalities of the nervous system are associated with lesion of osseous structures and the skin.
At present, nine different types of NF have been identified, which differ in number and localization of lesions. They are autosomal dominant with variable penetrance and occur in 1 of every 2,500 to 3,000 births. NF type 1 (corresponding to von Recklinghausen’s disease) and NF type 2 (acoustic) account for about 90% of all cases; they are related to genes located on chromosomes 17 and 22, respectively.
From a pathogenetic point of view, NF defects are generally attributed to neural crest derivatives. In fact, the main characteristics, such as café au lait spots, neurofibromas, and sphenoid bone dysplasia; are of neural crest origin.
Other findings, however, such as cerebrocortical heterotopias and optic gliomas, appear to be of mesodermal origin. Consequently, at present, it is not know whether features should be explained on the basis of the same gene expressed in different tissues or whether only neural crest cells and other cells (i.e., neural tube or mesodermal cells or both).
Usually, stigmata of NF are frequently present in the head and neck. In some cases, the massive and elective involvement of cephalic region produces separate entities, among them, cranio-orbital NF has recently been recognized.
The case reported below is referred to a 25-year-old patient suffering from neurofibromatosis localized in the cranio-orbital region, whose main problem was a pulsating right exophthalmos caused by herniation of the frontotemporal lobe through a defect of the greater wing of the sphenoid. The lesion was approached through a combined route (i.e., transfrontally and transfacially [upper eyelid incision]).
Cranio-orbital neurofibromatosis recostruction of the right orbital roof with cranial bone, removal of intracranial lesion.
In a second step enucleation and remodeling of the palpebral tissue was performed.
Hydroxylopatite endo-orbital implant and definitive eye prosthesis improved the final result.