OBJECTIVETo study clinic therapeutic effect about reconstruction of severe orbital and cul-de-sac deformity after the radiotherapy with transcranial orbitotomy advancement combining cascade free flap both dorsum pedis flap and anterior tibial fascial flap.

METHODSFive cases was subjected to orbital and cut-de-sac severe deformities after both operation and radiotherapy because of retinoblastoma. The technique included transcranial orbital advancement by anterior orbital osteotomy and rigid fixed with titanic plate by coronal incision, and meanwhile incising the cul-de-sac which would be extended circumference around the central incision separation, and then designing extent of cascade flap consisted of dorsum pedis flap and anterior tibial fascial flap according to the size of cul-de-sac defect and extent of temporal depression. Then, the aforementioned two parts of cascade flap were transplanted into cul-de-sac and temple respectively. There is either the superficial temporal artery and vein or facial artery and jugular vein to chose vascular anastomosis.

RESULTSAll flaps survived. After 3 to 6 months following up, the results showed satisfactory orbital contour and temporal depression improved significantly in all cases. After the conjunctival sac were fixiformed with prefabricated eye prosthesis mode about 3 months. 3 cases have good appearance with wearing eye prosthesis and the other 2 cases' appearance is poor. One of the poor appearance cases, with depressed eye socket, have orbital implant underlying conjunctival sac in secondary operation. The other one, with swallowed inferior fornix, is transplanted autogenous hard palatal mucosa into inferior fornix in secondary operation. In addition, delayed healing in donor site of dorsum pedis occurred in one of the 4 cases.

CONCLUSIONSIt is a reliable procedure about reconstruction of severe orbital and cul-de-sac deformity after both the operation and radiotherapy with transcranial orbitotomy advancement combining cascade free flap both dorsum pedis flap and anterior tibial fascial flap. All deformity was corrected by one staged procedure which lessen patient's suffering and shorten patient's hospital stay and spare patient's costs.