Orbital Floor

Jacqueline R. Carrasco


BASICS


DESCRIPTION


• Traumatic defect in the bony floor of the orbit


• Can extend from fractures of the inferior orbital rim


• Indirect (blowout) fractures of the orbital floor are not associated with fracture of the orbital rim.


EPIDEMIOLOGY


Incidence and prevalence variable


RISK FACTORS


• Male gender


• Younger age (15–30 years)


• Participation in sports


• Substance abuse


GENERAL PREVENTION


Wear eye protection when engaging in sports involving objects that move at high velocity (baseball, softball, hockey).


PATHOPHYSIOLOGY


Two theories:


• A nonpenetrating object strikes orbital entrance causing a sudden increase in intraorbital pressure. The contents of the orbit are compressed posteriorly toward the apex of the orbit. The orbital bones break at their weakest point, usually the posterior medial part of the floor in the maxillary bone.


• The striking object causes a compressive force at the inferior rim, which leads directly to buckling of the orbital floor.


ETIOLOGY


Trauma (see above)


COMMONLY ASSOCIATED CONDITIONS


• Globe rupture


• Hyphema/microhyphema


• Traumatic iritis


• Commotio retinae


• Choroidal rupture


• Traumatic optic neuropathy


DIAGNOSIS


HISTORY


• Inquire about the timing and specific circumstances of the trauma


• Classic history involves the orbital entrance being struck by an object larger than the diameter of the orbital opening (e.g., fist, dashboard, ball)


• Nausea, vomiting, and bradycardia can indicate entrapment


PHYSICAL EXAM


• Eyelid ecchymosis


• Eyelid edema


• Diplopia with limitation on upgaze, downgaze, or both


Forced duction test: Instill anesthetic eyedrops followed by lidocaine 2% gel. Grasp the insertion of the inferior rectus muscle through the conjunctiva with a toothed forceps, and attempt to rotate the globe up and down. Restriction when rotating the globe upward indicates possible entrapment.


• Enophthalmos


• Hypoglobus


• Infraorbital hypesthesia


• Emphysema of the eyelids and orbits


• Step-off deformity of orbital rim palpated


DIAGNOSTIC TESTS & INTERPRETATION


Imaging


CT scan of the orbits with coronal and axial views demonstrates a defect in the bony floor of the orbit with possible entrapment of soft tissue and/or extraocular muscle.


DIFFERENTIAL DIAGNOSIS


• Orbital hemorrhage and edema without a fracture: No fracture on CT


• Cranial nerve palsy: normal forced-duction test


TREATMENT


MEDICATION


• Broad-spectrum oral antibiotics, especially if patient has a history of sinusitis, diabetes, or is immunocompromised: cephalexin 250–500 mg p.o. q.i.d. or erythromycin 250–500 mg p.o. q.i.d. for 7 days


• Methylprednisolone (Medrol) dose pack if patient has extensive swelling


ADDITIONAL TREATMENT


General Measures


• No nose blowing


• Nasal decongestants


• Ice packs


Issues for Referral


• If not a surgical candidate, referral should be made to a general ophthalmologist to be seen within 7–10 days of the initial trauma.


• If a surgical candidate, referral should be made to an oculoplastic surgeon within 7–10 days of the initial trauma.


• Any patient with nausea, vomiting, or bradycardia secondary to entrapped extraocular muscle should be evaluated by an oculoplastic surgeon at the time of initial exam to evaluate the need for urgent repair.


Pediatric Considerations


A pediatric patient with an entrapped extraocular muscle should be evaluated by an oculoplastic surgeon at the time of initial exam to evaluate the need for urgent repair (24–48 hours).


SURGERY/OTHER PROCEDURES


• Not all fractures need to be repaired.


• Indications for surgical repair:


– Fracture involving at least 50% of the orbital floor, especially associated with large medial wall fractures on CT


– Enophthalmos greater than 2 mm that is cosmetically unacceptable to the patient


– Diplopia with limitation of upgaze and/or downgaze within 30° of primary gaze


• Should take place within 2 weeks of initial trauma


• Involves releasing entrapped tissue and placing an orbital implant to separate the orbit from the maxillary sinus


ONGOING CARE


FOLLOW-UP RECOMMENDATIONS


• Ophthalmologist


• Otolaryngologist/oral maxillofacial surgeon as needed


PATIENT EDUCATION


www.nlm.nih.gov/medlineplus/eyeinjuries.html


PROGNOSIS


Depends on the extent of associated injuries


COMPLICATIONS


• Decreased vision


• Diplopia


• Enophthalmos


• Infraorbital hypesthesia


• Orbital cellulitis


ADDITIONAL READING


• Egbert JE, May K, Kersten RC, et al. Pediatric orbital floor fracture—direct extraocular muscle involvement. Ophthalmology 2000;107:1875–1879.


• Harris GJ, Garcia GH, Logani SC, et al. Correlation of preoperative computed tomography and postoperative ocular motility in orbital blowout fractures. Ophthal Plast Reconstr Surg 2000;16:179–187.


• Hawes MJ, Dortzbach RK. Surgery on orbital floor fractures: influence of time of repair and fracture size. Ophthalmology 1983;90:1066–1070.


• Jordan DR, Allen LH, White J, et al. Intervention within days for some orbital floor fractures: the white-eyed blowout. Ophthal Plast Reconstr Surg 1998;14:379–390.


• Okulicz JF, Shah RS, Schwartz RA, et al. Oculocutaneous albinism. European J Eur Acad Dermatol Venereol 2003;17:251–256.


• Putterman AM, Stevens T, Urist MJ. Nonsurgical management of blowout fractures of the orbital floor. Am J Ophthalmol 1974;77:232–239.


CODES


ICD9


802.6 Closed fracture of orbital floor (blow-out)


802.7 Open fracture of orbital floor (blow-out)


871.0 Ocular laceration without prolapse of intraocular tissue


CLINICAL PEARLS


• Pediatric orbital blowout fractures with entrapment of extraocular muscles should be considered for urgent repair.


• Optimal time for nonentrapped, orbital floor fracture repair is within 2 weeks of the initial trauma.


• Orbital CT scans with axial and coronal cuts are the key for making the diagnosis and surgical planning.


• A “white-eyed” blowout fracture can occur, especially in pediatric population, with entrapped muscle, poor motility, and very little external signs. See White Eyed Blow Out Fracture.


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Nov 9, 2016 | Posted by in OPHTHALMOLOGY | Comments Off on Orbital Floor

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