Intraorbital tissue expansion in the management of congenital anophthalmos

Seven cases of intraorbital tissue expansion for the treatment of congenital anophthalmos or microphthalmos are presented. The ages of the patients at insertion of the expander ranged from 4 months to 8 years. A 4ml spherical tissue expander with a remote injection port was inserted into the affected orbit via a bicoronal approach. Expansion periods ranged between 4 months and 3 years and are continuing in 2 patients. Results were assessed by clinical examination, comparison of photographs, 3D CT scans and orbital measurements taken from axial CT scans which were compared with established normal values. Results confirmed enlargement of the orbit with expansion. Long-term expansion over several years established near normal bony growth patterns. Placement of the expander within the orbital soft tissue cone resulted in more symmetrical expansion than subperiosteal placement. An osteotomy releasing the lateral orbital wall in older children allows expansion of the orbit and may reduce the incidence of expander extrusion. Although intraorbital tissue expansion successfully induces orbital growth, improvement in the form and size of the congenitally deficient eyelids is less marked.