Role of the first aspartate residue of the "YxDTDS" motif of phi29 DNA polymerase as a metal ligand during both TP-primed and DNA-primed DNA synthesis

Neurofibromatosis is a systemic disease that often produces striking disfigurement. Orbital manifestations are common and include sphenoid dysplasia with or without infiltration of the periorbital soft tissues. The resultant deficiency of the posterolateral orbital wall may lead to protrusion of the temporal lobe into the orbit, displacement of the globe, and pulsatile exophthalmos. Treatment at our unit has consisted of transcranial orbital reconstruction with bone grafts and periorbital soft-tissue correction. Observation of complete bone graft resorption in one patient prompted an assessment of the Australian Craniofacial Unit's experience with particular attention paid to the stability of operative correction. Of 36 patients with head and neck neurofibromatosis treated during the period from 1981 to 1995, 14 patients underwent transcranial correction of orbital deformities secondary to sphenoid dysplasia. The treatment and outcomes of this transcranial group are reviewed. The most notable finding was that of recurrent globe pulsation in four patients following initial resolution. Computed tomography scans have documented partial to complete bone graft resorption in three of these patients. Titanium mesh is now being utilized to provide a more durable reconstruction.