Secondary CT Signs

•Occlusion of the sphenoid sinus/posterior cells of the ethmoid sinus

•Epidural temporo-basal hematoma

Additional Injuries

•Fracture of the lamina papyracea/fracture of the frontal sinus

•Zygomatic fracture, fractures of the orbital floor/ roof

•Air accumulation in the region of the optic chiasm, cavernous sinus, greater wing of the sphenoid

•Frontal – temporobasal contusions – subarachnoidal – subdural hemorrhage/hematoma

Operating Indications/Decompression

Decompression of the Orbital Cavity

The indication for decompression (orbitotomy) is given by an afferent disturbance of the optic nerve — amaurosis or progressive loss of vision — based on a retro bulbar hematoma. A liquor fistula, a pulsating exophthalmus (carotis-cavernous sinus fistula) and other general contraindications due to the trauma should be excluded.

Decompression of the Optic Canal

•Decompression of the optic nerve canal in conscious patient:

In the case of afferent nerve disturbances with progressive loss of vision or amaurosis based on radiological evidence of fractures in the retrobulbar orbital region or in the optic canal, surgical decompression of the nerve in the optic canal (transethmoidal decompression of the optic nerve) should be performed as soon as possible.

•Decompression of the optic nerve in unconscious patient:

There is an indication for an operative transethmoid decompression if there is direct or indirect radiological evidence of a retrobulbar trauma in the orbital region or in the neighboring region of the optic canal and if there is clinical evidence of an afferent disturbance of the optic nerve [alternative: presence of pathological visually evoked potentials (VEPs)] (Gellrich et al. 1996; Gellrich 1999):

Therapy/Prognosis

Decompression of the orbital contents and the optic canal is performed through an endonasal/transethmoidal,­ transfacial/transethmoidal, or a transfrontal/transcranial

neurosurgical approach. The operation has to be performed within the first 6 h following trauma (Yoshinao 1972; Fukado 1981; Krausen et al. 1981; Stoll et al. 1987, 1994; Sofferman 1988, 1991; Mann et al. 1991; Niho 1991; Mathog 1992; Rochels and Behrendt 1996; Koch and Lehnhardt 2000).

Decompression 8–10 h following trauma often results in a permanent reduction of vision or even an amaurosis (Kennerdell et al. 1976; Lädrach et al. 1999).

Even following prompt decompression, both microand macro-traumatic injuries to the optic nerve with acute loss of vision only have a reduced chance of recovery. In less than 20% of the cases, normal or nearly normal vision returns (Beuthner 1974; Dutton and AL-Qurainy 1991; Rochels and Behrendt 1996, 1997).

If there is not an immediate but a slow reduction of vision (edema - hematoma in the optic canal), early decompression will be successful in 20–30% (Beuthner 1974; Osguthorpe and Sofferman 1988) (Figs. 6.10 and 6.11).

Fig. 6.10  (a) Transfacial approach for transethmoidal-transsphe- noidal decompression of the optic nerve and the orbital cavity (mod. a. Weerda 1995). (b) Decompression of the optic nerve by ethmoidectomy and removal of the lateral wall of the sphenoid

wing (red: removed bony structures). (c) Endonasal/transethmoidal decompression of the orbit and the optic nerve after ethmoidectomy, resection of the orbital lamina of the ethmoid (lamina papyracea) and of the anterior and lateral walls of the sphenoid

Fig. 6.11  Transcranial decompression of the optic nerve (mod. a. Kastenbauer and Tardy 1995). Incision of the dura (a). Microscopic debridement with removal of the fragments of the

roof of the optic canal. (b) Incision of the optic nerve sheath. (c) Intraoperative view during transcranial exploration of the optic nerve (arrow) after CCMF fracture