TRAUMA: Orbital # Flashcards
Signs and symptoms of retrobulbar hemorrhage
Tensed proptosed eye Ophthalmoplegic eye Marcus Gunn sign (Rapid afferent pupillary defect) Binocular diplopia Chemosis Orbital pain Increased intraocular pressure Retinal signs- papilloedema, lack of central retinal artery pulsation, pale optic disc
Emergency management of retrobulbar hemorrhage
Medical
- mannitol 20% 2g/kg IV over 5mins
- dexa IV 8mg stat
- acetazolamide (carbonic anhidrase inhibitor) 500mg IV, 1000mg oral over 24hrs. -> reduce production of aqueous humor
Surgical
- lateral canthotomy
- cantholysis
Assessment of orbital injury
Direct and indirect pupillary reflexes Visual acuity Visual field Ocular tonometry Hertels measurement (for enophthalmos/ exophthalmos) Pupillary level (dystopia) Eye movement Shirmers tear test Intercanthal distance
Indications of CT brain in head injury
Moderate to severe head injury Deteriorating GCS LOC Penetrating injury Suspected skull fracture Large soft tissue injury of the scalp (hematoma or L/W) Amnesia Focal neurologic deficits CSF leaks
Advantages and disadvantages of CT Scan of head and neck for trauma
- Short examination time in emergency
- Good view and assessment of the bony structures to detect fracture
- Able to reconstruct 3D image
4.
Orbital blowout fracture and its presentation
Orbital injury in which the orbital rims are intact but forces exerted were transferred to weaker walls (usually the medial wall and floor of orbit medial to the infraorbital nerve) causing the walls to fracture out. As forces increases, fracture may extend posteriorly and circumferentially.
Presentation:
Enophthalmos
Limited eye movement
Binocular diplopia
What is forced duction test and what is its use?
A test involving grasping the rectus muscles and pulling it to see if theres any restriction.
This is to test if there is any muscular entrapment.
Superior orbital fissure syndrome causes and presentation. How to treat?
SOF contains CN III, IV, V1, VI
CNIII - pupillary dilation (dysfunction of pupillary constrictor muscle)
CN III, IV, VI - ophthalmoplegia
CN V1 - Anaesthesia of the forehead and loss of corneal reflex
Orbital apex syndrome.
Orbital apex includes SOF and Optic canal tensed proptosed eyes periorbital swelling retroorbital pain pupillary dilation (Marcus Gunn pupil) ophthalmoplegia Impaired visual acuity
Marcus gunn pupil indicates wht?
Injury to CN II where it causing afferent defect.
AKA Rapid afferent pupillary defect
How to test it - shine light to contralateral eye will lead to bilateral pupillary constriction. But when shine light on to the affected eye - ipsilateral pupil will dilate (not constrict).
What is a bowstring test?
Its to assess the medial canthal ligament.
By gently pulling the lateral canthal ligament, if mobility is detected when palpating the medial cathal attachment, then this confirms displaced fracture of medial wall with displacement of medial canthal ligament
Indications of nonsurgical conservative observation treatment of orbital fracture?
- minimal or undisplaced internal orbit fracture without disturbance in eye movements
- orbital fracture of the only functioning eye
- Globe injury, retinal tear, hyphema
- medically compromised
How do u manage orbital fracture conservatively?
Steroids for swelling
Sinus precautions especially when sinus is perforated from the orbital wall fracture
Management of the intraocular pressure (<30mm Hg) using mannitol, acetazolamide, steroid
Antibiotics if open injury
Indications of surgical treatment of orbital fractures
Enophthalmos Non resolving diplopia Globe malposition Comminuted orbital rim fracture White-eyed orbital fracture
Approaches for tx of orbital fractures
Existing laceration wound Subcilliary approach (floor, medial and lateral wall - with extension lateral canthotomy) Transconjuctival approach (floor, medial and lateral wall -with extension lateral canthotomy) Infraorbital approach (floor) Transmaxillary approach (floor) Transnasal approach (floor) Transcuruncular approach (medial wall + transconjuctival usually for floor exposure) Coronal approach (roof, medial and lateral walls) Lateral eyebrow (ZF suture) Upper blepharoplasty approach (lateral wall and ZF suture)
Materials used for orbital floor recons
Autogenous bone grafts (calvarium, iliac or split rib) Alloplastic materials - Medpor (PPE) - Teflon (PTFE) - Silastic Titanium mesh
Complications of orbital fracture treatments
orbital hematoma Ectropion (subciliary > transconj; lat canthotomy; elderly) entropion persistent diplopia postoperative/posttraumatic enophthalmos
What are indications of IMMEDIATE surgical treatment of orbital fracture?
White-eyed blowout fracture
Globe herniation
Unresolved retrobulbar hemorrhage
Optic nerve injury (orbital apex syndrome)
What are the consequences in delaying immediate surgical tx of orbital fracture?
Muscle necrosis, defect in range of movement, diplopia
Loss of vision
When can you delay orbital recon?
Adult
Massive edema
What is a white-eyed orbital fracture
A blow out fracture in pediatrics whereby the bones are softer
Little or no clinical evidence of soft tissue trauma (edema, ecchymosis).
Diplopia with restriction of vertical gaze
Lack of enophthalmos
Radiologic signs of minimal/no bone displacement.
May or may not be signs of orbital tissue herniation
postoperative enophthalmos
Apparent enophthalmos once swelling has subsided.
1cc of volume loss will cause 1.5mm enophthalmos
caused by:
improper volume correction
orbital fat atrophy
contraction of retrobulbar tissues
What is the volume of orbit
30cc
Types of NOE fracture
Type 1 - medial canthal ligament still attached to a single large fragment of fractured bone on the medial wall
Type 2 - comminuted fracture but the MCL still attached to a segment of bone and bone segment could be free and mobile
Type 3 - comminuted fracture and MCL is detached from any bone segments
Significance of classificaiton of NOE fracture
Type 1 - requires ORIF with small plates and screws
Type 2 - requires transnasal canthopexy wiring prior to ORIF
Type 3 - requires transnasal canthopexy wiring of the MCL using cantilever technique onto the plates
