Maxillofacial Flashcards
A 50-year-old man comes to the office for revision of a bony defect in the skull 1 year after undergoing cranioplasty. Physical examination shows a 4 × 4-cm depression in the skull. Reconstruction with methyl methacrylate is planned. Which of the following properties is the primary advantage of the use of methyl methacrylate over other biomaterials? A) Bony ingrowth B) Easy prefabrication C) Endothermic D) High strength E) Resistance to infection
D) High strength
Methyl methacrylate has a high compression strength.This biomaterial has been used extensively for reconstruction of traumatic skull defects. The material is formed by mixing powdered polymer with liquid monomer. The reaction is highly exothermic. Advantages to its use include low cost, increased strength (relative to surrounding bone), and ready availability. Methyl methacrylate does not demonstrate bony incorporation or ingrowth. This property makes it susceptible to infection throughout the duration of the reconstruction. Although it is an appropriate choice for reconstruction of defects in adults, the product is inert and fixed; therefore, it does not adapt with growth in children. Methyl methacrylate can be prefabricated, but it requires complex planning.
Strength of methyl methacrylate
High compression strength
Reconstruction with methyl methacrylate
Powdered polymer is mixed with liquid monomer, creating a highly exothermic reaction.
Why is methyl methacrylate susceptible to infection?
It does not demonstrate bony incorporation nor ingrowth
Pros / cons of methyl methacrylate
Pros: Low cost, increased strength (relative to surrounding bone), and ready availability.
Cons: Does not demonstrate bony ingrowth (susceptible to infection), inert/fixed (does not adapt to growth in children), exothermic reaction
A 72-year-old man is brought to the emergency department after he sustained injuries in a high-speed motor vehicle collision as an unrestrained backseat passenger. He has chronic obstructive pulmonary disease and a 40-pack-year history of smoking. The following measurements are obtained:
Heart rate 88 bpm
Respirations 18/min
Blood pressure 115/70 mmHg
Oxygen saturation 98% on 6 L by face mask
Physical examination shows severe swelling in the face. He is coughing blood and mucus from his mouth and nose. Gross malocclusion is noted, but full dentition is present with no dental caries. CT scan shows a naso-orbital-ethmoid fracture, Le Fort III fracture, palatal fracture, and comminuted mandibular body and angle fractures. Which of the following is the most appropriate method of airway management during surgical repair of this patient’s fractures? A) Cricothyroidotomy B) Nasotracheal intubation C) Placement of an orotracheal tube D) Tracheostomy E) Use of a laryngeal mask airway
D) Tracheostomy
The patient described has complex facial fractures involving both the midface and the lower face. He also has a significant history of smoking. This particular patient is likely to have continued respiratory issues postoperatively, making pulmonary management challenging. The placement of a tracheostomy at the time of surgery will allow the surgical team full access to all of the patient’s facial fractures and will facilitate the patient’s pulmonary care postoperatively.
Nasotracheal intubation is contraindicated in a patient with a naso-orbital-ethmoid fracture because the presence of a tube can complicate fracture reduction.Generally, placement of an orotracheal tube is feasible and successful in most facial fracture patients. However, given the complex nature of fractures in the scenario described, the patient will need to be placed into mandibular-maxillary fixation during surgery to obtain normal occlusion and possibly for an indefinite period of time after surgery.
Indication for cricothyroidectomy
Cricothyroidotomy is indicated occasionally as an emergency procedure when there is concern for acute control of the patient’s airway.
A 22-year-old man is brought to the emergency department after sustaining injuries during an all-terrain vehicle collision. Clinical examination shows telecanthus and periorbital ecchymosis. A fracture dislocation involving which of the following structures is most likely contributing to the telecanthus? A) Inferior rectus muscle tendon B) Lateral canthal tendon C) Lateral rectus muscle tendon D) Medial canthal tendon E) Medial rectus muscle tendon
D) Medial canthal tendon
The medial canthal tendon attaches to:
The medial canthal tendon is a fibrous band attached to the medial orbital wall (frontal bone and lacrimal crest).
A 42-year-old woman is brought to the emergency department after sustaining traumatic fractures of the right orbit and zygoma in a motor vehicle collision. Physical examination shows localized edema. Which of the following indications is most likely for immediate ophthalmologic consultation? A) Corneal abrasion B ) Diplopia C) Eyelid ptosis D) Hyphema E) Subconjunctival hemorrhage
D) Hyphema
Hyphema is defined as blood within the anterior chamber of the eye. It is caused by tearing of the vessels within the iris as a result of trauma.
Neither diplopia nor traumatic ptosis warrantsemergent consultation.
Hyphema
Hyphema is defined as blood within the anterior chamber of the eye. It is caused by tearing of the vessels within the iris as a result of trauma.
Blood within the eye is worrisome because clotting can interfere with fluid egress from the anterior chamber, leading to the development of glaucoma. Immediate ophthalmology consultation, urgent intraocular pressure measurement, andslit-lamp examination should be performed to determine the extent of hemorrhage.
Subconjunctival hemorrhage
Subconjunctival hemorrhage, on the other hand, stains the bulbar conjunctiva with blood from the site of a nearby fracture.
A 24-year-old man comes to the office for follow-up examination 2 weeks after undergoing open reduction and internal fixation of a fracture of the right zygomaticomaxillary complex. The procedure was performed with intraoral and subtarsal eyelid incisions. Physical examination shows ectropion of the right lower eyelid. Ophthalmologic examination shows no vision abnormalities; the cornea is intact. Which of the following is the most appropriate management of the ectropion?
A) Coverage with a tarsoconjunctival flap
B) Lateral canthoplasty
C) Placement of an allograft to the middle lamella
D) Skin grafting to the external lamella
E) Observation with massage
E) Observation with massage
Conservative therapy is recommended and includes tarsorrhaphy, massage, and application of ophthalmic steroid ointment or drops.
What percent of patients will require operative revision for globe or eyelid malposition after orbital fracture reconstruction?
Complications related to the eyelid are common following orbital fracture reconstruction. Approximately 10 to 20% of patients will require some operative revision for globe or eyelid malposition. This is because of the edema and swelling present at the initial operation. As a result, the incidence of scleral show and ectropionis also high because of eyelid retraction.
Conservative therapy is recommended and includes tarsorrhaphy, massage, and application of ophthalmic steroid ointment or drops.
A 20-year-old man comes to the office with severe malocclusion 8 weeks after sustaining injuries during a motor vehicle collision. Physical examination shows healing lacerations, loss of sensation in the infraorbital nerve distribution on the affected side, and no orbital rim step-off deformity. CT scan shows a unilateral orbital blowout fracture with a mid face fracture. No mandibular fracture is identified. Which of the following is the most appropriate initial step in management?
A) Le Fort I osteotomy with fixation
B) Maxillomandibular fixation
C) Open reduction and internal fixation of the ZMC fracture
D) Open reduction and reconstruction of the orbital floor fracture
A) Le Fort I osteotomy with fixation
Because the patient is 8 weeks out from the injury, the fracturelines are immobile and a Le Fort I osteotomy and maxillomandibular fixation would be required to correct the malocclusion.
A 27-year-old man is brought to the emergency department 1 hour after sustaining a knife wound to the left cheek. Physical examination shows a wound just anterior to the left ear that extends intraorally. A photograph is shown. He is able to elevate the brow, close the eyes, smile, and evert the lower lip. The laceration is irrigated thoroughly. Which of the following is the most appropriate next step in management?
A) Application of wet-to-dry dressings
B) Cannulation of Stensen duct
C) Closure of the facial wound and administration of sialogogues
D) Starch-iodine test
E) Testing of the distal branches of the facial nerve with a stimulator
B) Cannulation of Stensen duct
After ruling out facial nerve injury, the next priority in management of a cheek laceration is to rule out injury to the parotid (Stensen) duct. Failure to repair a parotid duct laceration can result in a salivary fistula or sialocele.
is not necessary to explore the facial nerve when the patient has clinically intact facial motor function. Such exploration risks inadvertent injury to the nerve.
Failure to repair a parotid duct laceration can result in:
Failure to repair a parotid duct laceration can result in a salivary fistula or sialocele.
How is injury to the parotid duct ruled out?
A small amount of methylene blue dye injected via an intravenous catheter, introduced through the ductal papilla in the mouth opposite the maxillary second molar, may be effective in identifying lacerations.
Name of the parotid duct
Stensen duct
How is injury to the parotid duct repaired?
Whenever possible, it is best to repair lacerations primarily using fine suture (eg, 8-0 nylon) over a stent.
If the duct cannot be repaired because of extensive damage, ligation of the duct can be considered
Salivation vs a parotid/parotid duct injury
Anticholinergic medications, such as glycopyrrolate, can be administered to limit salivary secretion during healing and to help prevent salivary fistula or sialocele formation from an unrecognized ductal injury or glandular laceration.
Starch-iodine test
The starch-iodine test is used to assess gustatory sweating thought to occur because of inappropriate sympathetic reinnervation of the facial sweat glands after parotid surgery.
Avulsions occur most commonly at which of the following layers of the scalp? A) Aponeurotic layer B) Loose areolar layer C) Pericranium D) Skin E) Subcutaneous layer
B) Loose areolar layer
Layers of the scalp
The layers of the scalp can be remembered by the mnemonic SCALP: skin, subcutaneous tissue, aponeurotic layer (also called the galea), loose areolartissue, and pericranium.
Associations of layers of the scalp
The skin, subcutaneous tissue, and galea are intimately fused and move as a unit. These layers are separated from the pericranium by a layer of areolar tissue. This layer allows easy movement of the scalp and provides a space for fluid accumulation.
Avulsions occur most commonly at which of the layers of the scalp?
Loose areolar layer
The other layers of the scalp are separated from the pericranium by a layer of areolar tissue. This layer allows easy movement of the scalp and provides a space for fluid accumulation. It is through this layer that separation most easily occurs in the setting of trauma to or surgical reflection of the scalp.
What crosses the loose areolar layer of the scalp / clinical significance?
Emissary veins cross the loose areolar space as they drain the scalp into the intracranial venous sinuses. Because of the potential for accumulation of fluid in the loose areolar tissue, an infection or abscess in this layer may lead to meningitis or septic venous sinus thrombosis. However, the incidence of such events is low.
What is considered the strength layer of the scalp?
The galeal aponeurosis is considered the strength layer of the scalp
What is the galeal aponeurosis continuous with?
The galeal aponeurosis is considered the strength layer of the scalp and is contiguous with the frontalis and occipitalis muscles and the temporoparietal fascia laterally.
Blood supply to the pericranium
The pericranium is tightly adherent to the skull. It derives its blood supply from the diploic circulation via a multitude of perforating blood vessels and can serve as a vascularized bed for accepting skin grafts.
A 22-year-old man is brought to the emergency department after sustaining injuries to the head during a high-speed motor vehicle collision. Examination shows fluid draining from the nostrils. Beta-2 transferrin test on the fluid is positive. CT scan shows a frontal sinus fracture. The anterior and posterior tables are nondisplaced. Which of the following is the most appropriate next step?
A) Cranialization of the frontal sinus
B) Dural repair
C) Obliteration of the frontal sinus
D) Reduction and fixation of the anterior-table frontal sinus
E) Observation
E) Observation
A positive beta-2 transferrin test result indicates a cerebrospinal fluid (CSF) rhinorrhea. The first priority is to seal the leak. The patient should be observed before proceeding. The head of the bed should be elevated, and consideration should be given to placement of a lumbar CSF drain. If the leak does not resolve, surgical intervention should be planned.Once the CSF rhinorrhea has resolved, operative repair of the facial fractures can begin. After the premorbid occlusion is established, the mandible fractures are plated sequentially.
Cranialization is reserved for displaced posterior table frontal sinus fractures. Dural repair is not needed at this stage as the CSF leak will probably seal on its own. Obliteration of the frontal sinus may be required if the CSF rhinorrhea fails to respond to conservative treatmen
Beta-2 transferin test
A positive beta-2 transferrin test result indicates a cerebrospinal fluid (CSF) rhinorrhea.
Indication for cranialization of the frontal sinus
Cranialization is reserved for displaced posterior table frontal sinus fractures.
A 25-year-old man comes to the office for a follow-up examination because he has had intraoral drainage and pain and swelling over the right mandible for the past 24 hours. Ten days ago, he underwent maxillomandibular fixation followed by rigid internal fixation. CT scan of the head shows a soft-tissue collection along the right mandibular body; there is no evidence of osteomyelitis, and the rigid fixation is stable. Which of the following is the most appropriate management?
A) Incision and drainage
B) Incision and drainage, removal of hardware, andexternal fixation
C) Incision and drainage, removal of hardware, and maxillomandibular fixation
D) Incision and drainage, removal of hardware, and vascularization of fibula flap transfer
E) No additional intervention is needed
A) Incision and drainage
Management of these infections requires adequate incision and drainage as well as intravenous antibiotics and mouth care. If the source of infection is an exposed infected tooth root, it should be removed. It is important that rigid internal fixation be maintained until the bone fracture segments have ossified because nonrigid fixation, such as external fixation ormaxillomandibular fixation, can lead to worsening of infection.Removal of the internal hardware is rarely necessary unless the hardware is actively infected and loosened because of bone involvement (osteomyelitis).Repair with vascularized fibula flap transfer is also not indicated because there is no evidence for osteomyelitis or extensive bone loss.
What is the most common complication after mandibular fracture repair?
Postoperative infections are the most common complication after mandibular fracture repair, with an incidence ranging from 0.4 to 32%.
Management of infection after mandibular repair
Management of these infections requires adequate incision and drainage as well as intravenous antibiotics and mouth care. If the source of infection is an exposed infected tooth root, it should be removed. It is important that rigid internal fixation be maintained until the bone fracture segments have ossified because nonrigid fixation, such as external fixation ormaxillomandibular fixation, can lead to worsening of infection.
Removal of the internal hardware is rarely necessary unless the hardware is actively infected and loosened because of bone involvement (osteomyelitis)
An 83-year-old man undergoes radiation therapy and surgical resection and coverage with a cranial bone graft to treat meningioma. The graft becomes infected and is removed 6 weeks after the procedure. One year later, the patient is scheduled to undergo reconstruction of the resulting 23-cm2 defect in the skull. Which of the following is a relative contraindication for the subsequent use of hydroxyapatite in this patient? A ) Age of patient B ) History of infection C ) History of radiation D ) Location of defect E ) Size of defect
C ) History of radiation
Hydroxyapatite cement is widely used in cranioplasty. In one study, the complication rate of the use of hydroxyapatite in patients who have received irradiation to the scalp was 100%. Therefore, its use is not recommended in this population.
Hydroxyapatite and skull infection
Reduction in theincidence of infection has been shown when a period of 1 year has elapsed between the initial injury or infection and the reconstruction with hydroxyapatite.
Use of hydroxyapatite in frontal areas causes twice the incidence of infection than in its use in all other areas.
Maximum defect size for Hydroxyapatite skull repair
Hydroxyapatite is approved by the FDA for reconstruction of bony defects up to 25 cm2 in size.
Contraindications to hydroxyapetite skull repair
History of radiation
Large full thickness defects in pediatric patients
< 1 year after infection
> 25 cm^2 defect
When reattaching the medial canthal ligaments during a transnasal canthal wiring procedure, which of the following is the most appropriate placement of the drill holes with respect to the lacrimal fossa? A ) Anterior and inferior B ) Anterior and posterior C ) Posterior and inferior D ) Posterior and superior
D ) Posterior and superior
When treating congenital and traumatic deformities of the naso-orbital-ethmoid region, reconstruction and reattachment of the medial canthal tendons are often necessary. Overcorrection with this procedure is essentially impossible, and every effort should be made to prevent relapse and recurrent telecanthus. To this end, the transnasal wires containing the medial canthus should be placed through drill holes positioned posterior and superiorto the posterior crest of the bony lacrimal fossa.
Drill hole placement when reattaching the medial canthal ligaments during a transnasal canthal wiring procedure
Posterior and superior.
Overcorrection is virtually impossible.
A 17-year-old girl is brought to the emergency department after she was hit in the left eye with a batted softball. Physical examination shows increased intraorbital pressure and decreasing visual acuity. Review of the CT scan confirms fracture of the orbital floor. Which of the following is the most appropriate immediate management?
A ) Administration of mannitol followed by exploration of the orbital floor
B ) Anticoagulation
C ) Exploration of the orbital floor and repair with a bone graft
D ) Exploration of the orbital floor and repair with synthetic material
E ) Lateral canthotomy and cantholysis
E ) Lateral canthotomy and cantholysis
Immediate lateral canthotomy and cantholysis are the most appropriate management of the condition described. Retrobulbar hematoma or orbital hemorrhage can follow either a direct injury to the orbital contents or a fracture that involves surrounding bones. Symptoms and signs include pain, reducing visual acuity, history of trauma, periorbital/lid hematoma, chemosis, proptosis, raised intraocular pressure, and ophthalmoplegia.
A delayed repair of the orbital fracture, generally within one week of the trauma, is performed if necessary.Medical treatment of raised intraorbital pressure with mannitol or dexamethasone should be regarded as an adjunct to surgery. The first line of treatment is surgical, and lateral canthotomy at the bedside is the most effective immediate treatment for increased intraorbital pressure
Therapeutic window before permanent damage from retrobulbar hematoma
There is a narrow therapeutic interval of 90 minutes before permanent damage to vision may occur.
A 33-year-old man is brought to the emergency department after sustaining injuries to the face during a snowmobile collision. (Axial CT scan is shown: A comminuted fracture of the frontal sinus is shown in the CT scan, with significant displacement of fragments involving both the anterior and posterior frontal sinus walls and the region of the nasofrontal duct.) Which of the following is the most appropriate management?
A ) Ablation of the frontal sinus
B ) Cranialization and reconstruction of the anterior frontal sinus wall
C ) Obliteration of the frontal sinus
D ) Observation with x-ray studies monthly
E ) Reconstruction of the nasofrontal duct and anterior and posterior frontal sinus walls
B ) Cranialization and reconstruction of the anterior frontal sinus wall
A comminuted fracture of the frontal sinus is shown in the CT scan, with significant displacement of fragments involving both the anterior and posterior frontal sinus walls and the region of the nasofrontal duct. The most appropriate treatment is cranialization and reconstruction of the anterior wall to restore normal forehead contour and protect the brain.
Reconstruction involves preserving sinus mucosa and reducing fractures of the nasofrontal duct and sinus walls. There are currently no data to support this technique, and in the patient described it could to lead to mucocele development as the nasofrontal duct became scarred and obstructed postoperatively
Procedure for cranialization of the frontal sinus
Cranialization involves removing the posterior frontal sinus wall to make the sinus part of the intracranial space and blocking the nasofrontal duct, typically with bone or a pericranial flap so that sinus mucosa is excluded from the intracranial space. The anterior frontal sinus wall is also reconstructed as part of this procedure to restore normal forehead contour and to protect the brain.
Procedure for ablation of the frontal sinus
Ablation (or exenteration) involves removing the anterior frontal sinus wall and allowing the skin to collapse in on the posterior wall, if it is intact, or on the dura if the posterior wall requires removal as well (as it would in this scenario). Ablation is appropriate only in extreme cases of acute infection that require open drainage and removal of infected bone.
Procedure for obliteration of the frontal sinus
Obliteration of the frontal sinus involves removing the sinus mucosa and burring the bony walls to remove mucosal invaginations, plugging the nasofrontal duct, and filling the sinus cavity with fat, muscle, bone, or alloplasts.
When is observation appropriate for frontal sinus fracture?
Observation is appropriate for minimally or nondisplaced fractures of the frontal sinus that do not involve the nasofrontal duct or do not acutely obstruct the nasofrontal duct. Regular plain x-ray studies should be obtained for several months afterward to monitor for development of a frontal sinus mucocele, which requires surgical treatment.
A 41-year-old man was punched in the eye two days ago and now has numbness in his cheek and double vision. Physical examination shows paresthesias in the V2 distribution, edema of the eyelids, and proptosis. Diplopia occurs at 40 degrees of upward gaze, but there are no definite signs of entrapment. A coronal CT is shown (~75% of the floor). Which of the following is the absolute indication for repair of the orbital floor fracture in this patient?
A ) Diplopia on upward gaze
B ) Extent of orbital floor loss
C ) Medial maxillary sinus wall fracture
D ) Medial orbital wall fracture
E ) Paresthesia between the lower eyelid and upper lip
B ) Extent of orbital floor loss
The absolute indication for repair of the orbital floor fracture in the patient described is the CT finding of loss of greater than 50% of the orbital floor. Without repair, this patient is prone to enophthalmos and long-term diplopia.
When is diplopia / extra ocular eye movement disturbance an indication for orbital floor fracture repair
Diplopia, without evidence of entrapment, is not an absolute indication for operative repairof orbital floor fractures, especially when not within 20 to 30 degrees of primary gaze. Diplopia in extreme gazes is not particularly dysfunctional; therefore, it is only a relative indication for surgery. Definite entrapment noted on examination would be an indication for surgery.
Operative repair should be performed when an orbital floor fracture is at what %?
> 50%
Injury of the infraorbital nerve in orbital floor fractures
Numbness between the lower eyelid and upper lip indicates injury to the infraorbital nerve, which is present in nearly all orbital floor fractures. It is usually a neurapraxic injury, which improves to some degree with time.
A 20-year-old man is undergoing open reduction and internal fixation of a nasoorbital-ethmoid fracture. Reconstruction of the medial canthal attachments using a transnasal approach is required. Which of the following best describes the correct placement of drill holes with respect to the posterior lacrimal crest during transnasal wiring? A ) Anteroinferior B ) Anterosuperior C ) Posteroinferior D )Posterosuperior
D )Posterosuperior
Why overcorrect when performing transversal wiring of the medial cants after an NOE fracture?
The drill holes for the transnasal wires attached to the medial canthal ligaments are placed 1 to 2 mm above and behind the lacrimal fossa or posterior and superior to the posterior lacrimal crest. Clinical confirmation of slight overcorrection is warranted because relapse is common, and telecanthus is a likely postoperative occurrence despite attempts at overcorrection.
A 42-year-old man comes to the office for consultation regarding the appearance of the right eye 10 months after sustaining a fracture of the right orbitozygomatic complex and multiple lacerations in a motor vehicle collision. He was unable to undergo treatment of the fractures because of other injuries. A photograph is shown. Which of the following is the most likely cause of the enophthalmos? A ) Atrophy of globe fat B ) Cicatrix of adnexal tissue C ) Eyelid lacerations D ) Increased orbital volume
D ) Increased orbital volume
Posttraumatic enophthalmos is primarily the result of:
Posttraumatic enophthalmos is primarily the result of increased bony orbital volume. Atrophy of globe fat and cicatrix of adnexal tissue may also contribute to enophthalmos, but minimally.
Posttraumatic enophthalmos results from displaced zygoma fractures, medial wall or floor blow-out fractures, and nasoorbito-ethmoidal fractures with disruption of the medial wall resulting in increased orbital volume.
Enophthalmos is best assessed via:
Enophthalmos is best assessed on submental view to evaluate globe projection.
A 43-year-old woman has periodic drainage of clear fluid from the nose three months after she sustained severe trauma to the face during a motor vehicle collision. She is concerned that the drainage may be cerebrospinal fluid. Which of the following tests of nasal secretions in this patient is most specific for leakage of cerebrospinal fluid?
A ) Determination of protein content
B ) Double halo sign
C ) Glucose dipstick
D ) Measurement of beta-2 transferrin level
E ) Measurement of potassium level
D ) Measurement of beta-2 transferrin level
Although decreased protein and potassium levels are associated with CSF leakage, these tests are not as specific for CSF. The test for double halo sign (fluid placement on a gauze pad or filter paper and observation for double halo formation) has a sensitivity of 78% but a false positive rate of 75%. Glucose dipstick testing was the first technique used to detect CSF. It is based on the principle that the glucose content of CSF exceeds that of mucus or blood.
A 24-year-old woman is brought to the emergency department after being involved in a motor vehicle collision. Physical examination shows multiple minor abrasions of the face. Clear rhinorrhea is noted. CT of the head shows a nondisplaced fracture of the posterior table of the frontal sinus. No other serious injuries are noted. Thepatient is admitted to the hospital, and antibiotic therapy is initiated. Which of the following is the most appropriate next step in management?
(A)Bed rest, head elevation, and observation
(B)Cranialization of the frontal sinus
(C)Craniotomy and repair of the dural tear
(D)Lumbar puncture and drainage of spinal fluid
(E)Obliteration of the frontal sinus
(A)Bed rest, head elevation, and observation
The patient described has a nondisplaced fracture of the posterior table of the frontal sinus with a cerebrospinal fluid (CSF) leak and should be treated with antibiotic coverage and maneuvers to facilitate spontaneous resolution of the leak. These include bed rest and head elevation greater than 30 degrees. If the CSF leak persists for more than four days, spinal drainage is recommended. Prolonged CSF leakage for longer than seven to 10 days requires craniotomy, repair of the dural laceration, and either obliteration of the sinus or cranialization.
Initial management for frontal sinus fracture with CSF leak
A nondisplaced fracture of the posterior table of the frontal sinus with a cerebrospinal fluid (CSF) leak should be treated with antibiotic coverage and maneuvers to facilitate spontaneous resolution of the leak. These include bed rest and head elevation greater than 30 degrees.
If the CSF leak persists for more than ________, spinal drainage is recommended.
If the CSF leak persists for more than four days, spinal drainage is recommended.
CSF leakage for __________ requires craniotomy, repair of the dural laceration, and either obliteration of the sinus or cranialization.
CSF leakage for longer than seven to 10 days requires craniotomy, repair of the dural laceration, and either obliteration of the sinus or cranialization.
Treatment of isolated anterior frontal sinus fracture w/o depression
No required surgical treatment
Treatment of isolated depressed anterior frontal sinus fracture
Surgical correction to restore aesthetic contour
Treatment of isolated anterior frontal sinus fracture with frontonasal duct injury
Removal of sinus mucosa with obliteration of the sinus.
Treatment of posterior frontal sinus fracture w/o displacement, CSF leakage or frontonasal duct involvement
Antibiotic treatment only
Treatment of posterior frontal sinus fracture w/o displacement, but with CSF leakage
Initially treat conservatively with antibiotics only.
Should the leakage persist for longer than 10 days despite measures to resolve spontaneously, a craniotomy with dural repair is required. This procedure is usually done in conjunction with neurosurgical colleagues.
Treatment of posterior frontal sinus fracture w/ displacement,
Displaced posterior wall fractures require exploration with repair of any dural tears and either sinus obliteration or cranialization. Cranialization involves removal of the entire posterior table, plugging of the frontonasal duct, repair of any dural lacerations, and separation of the intracranial cavity from the aerodigestive tract. The frontal lobe is then expected to fall into and fill the previous sinus cavity.
A 12-year-old boy is brought to the emergency department because of double vision six hours after sustaining a blow to the eye with an elbow while jumping on a trampoline. He has had pain since the incident but has not had loss of consciousness. He had one episode of nausea and vomiting before arrival. Pulse rate is 45 bpm, respirations are 18/min, and blood pressure is 110/80 mmHg. Examination shows photophobia, periorbital ecchymosis, and restriction of extraocular motion. CT of the head shows a fracture of the orbital floor. Which of the following is the most appropriate time for surgical repair of the fracture? (A)Emergently (B)1 to 3 Days (C)4 to 7 Days (D)8 to 14 Day
(A)Emergently
Observation alone is not indicated for entrapment with nausea, vomiting, and oculocardiac reflex. Recent publications in the ophthalmologic literature emphasize the importance of urgent surgical intervention to prevent ocular muscle damage, improve postoperative function, and decrease the need for additional surgery.
A 42-year-old man is brought to the emergency department 30 minutes after sustaining trauma to the face in a motor vehicle collision. Physical examination shows periorbital ecchymoses on the right, malar flattening, and enophthalmos. Neurologic examination shows numbness on the upper right lip. Radiographs show a displaced zygomaticomaxillary complex fracture. Anatomic reduction of each of the following is required in this patient EXCEPT (A)greater wing of the sphenoid (B)inferior orbital rim (C)nasomaxillary buttress (D)zygomaticofrontal suture (E)zygomaticomaxillary buttress
(C)nasomaxillary buttress
Reduction of the nasomaxillary buttress is not typically involved inthis type of fracture pattern.
Approximately ______% of patients with orbital fractures develop enophthalmos because of increased bony intraorbital volume. This is most frequently associated with __________________.
Approximately 15% to 22% of patients with orbital fractures develop enophthalmos because of increased bony intraorbital volume. This is most frequently associated with a zygomaticomaxillary complex fracture that has not been reduced adequately.
Reduction of which fractures is important in fixing a ZMC fracture
- Appropriate reduction of the ZMC complex
- Appropriate anatomic reduction of the greater wing of the sphenoid and lateral wall of the orbit is obtained after reduction the ZMC - - Correct reduction of the inferior orbital rim, zygomaticofrontal suture, and zygomaticomaxillary buttress is also important
Which of the following fractures of the facial bones is most common during childhood? (A)Frontal sinus (B)Le Fort (C)Nasal (D)Orbital
(C)Nasal
Most common facial fractures in pediatric patients
Mandible fractures (32-65%) Nasal fractures (12-45%) Orbital fractures (14-16%) Le Fort fractures (2-8%) Frontal sinus fractures - rare, except in teenage years when pneumatization of the sinus is approaching its completion.
A 12-year-old girl is brought to the emergency department after she sustained injuries in a motor vehicle collision. Physical examination shows extensive lacerations of the right medial orbit and forehead (shown) with complete transection of the medial canthal tendon (MCT). For effective reattachment of the MCT with transnasal wiring, which of the following is the most appropriate
direction of resuspension of the tendon in relation to the anterior lacrimal crest?
(A)Anterior and inferior
(B)Anterior and superior
(C)Directly horizontal
(D)Posterior and inferior
(E)Posteriorand superior
(E)Posteriorand superior
Anatomy of the medial canthal tendon
The medial canthal tendon (MCT) consists of three limbs:
1) a prominent anterior limb that inserts medially on the anterior lacrimal crest
2) a thinner posterior limb that attaches to the posterior lacrimal crest
3) a vertical limb of fascia that inserts on the medial orbital rim inferior to the nasal frontal suture.
A 70-year-old woman is brought to the emergency department after a fall. Examination shows periocular ecchymosis, epistaxis, and a bluish bulge of the septal mucosa. No other serious injuries are noted. CT shows fracture of the nasal septum. Which of the following is the most appropriate next step in management?
(A)Administration of intranasal oxymetazoline (Afrin)
(B)Drainage of hematomas and resection of septal cartilage
(C)Evacuation of hematomas through a direct incision
(D)Nasal packing only
(E)Needle aspiration of hematomas
(C)Evacuation of hematomas through a direct incision
Treatment of septal hematoma after trauma
Evacuation through a direct incision
Procedure for evacuation of a septal hematoma
Septal hematomas should be treated promptly with an L-shaped incision over the hematoma with thorough evacuation using suction and irrigation. This can be followed by loose repair of the incision to allow drainage and quilting sutures to prevent reaccumulation. It should be followed by internal nasal packing, systemic antibiotic coverage, and close follow-up to ensure absence of reaccumulation.
Generally, although septal hematomas tend to be bilateral, they should not be incised on both sides because through-and-through septal perforation may occur. If the entire hematoma cannot be evacuated with a unilateral approach, the incisions on each side should be made at different levels.
Why not resect septal cartilage at time of drainage of septal hematoma?
Resection of septal cartilage at the time of drainage should be avoided because septal perforation may occur.
A 30-year-old woman sustains a nasoethmoid fracture in a motor vehicle collision. Radiographs of the fracture site show extensive fracture comminution that extends into the point of insertion of the medial canthal tendon. Transnasal medial canthopexies are to be performed for fracture fixation. The classification of this fracture is Markowitz and Manson type 3. Which of the following is the most appropriate management? (A)External nasal splint fixation (B)Kirschner wire fixation (C)Rigid plate fixation (D)Transnasal wiring
(D)Transnasal wiring
The Markowitz and Manson system
Used to classify nasoethmoid fractures according to the status of the bone fragment into which the medial canthal tendon inserts
The Markowitz and Manson system : Type 1 fracture
NOE Fracture: In a type 1 fracture, there is a large central fragment. The fragment can be reduced and a plate can be applied to stabilize the nasoethmoid region.
The Markowitz and Manson system : Type 2 fracture
Type 2 fractures exhibit comminution of the central fragment, but the point of insertion of the medial canthal tendon remains intact.
The Markowitz and Manson system : Type 3 fracture
Patients with type 3 fractures have extensive comminution of the segmentthat extends into the point of tendon insertion. Because stabilization with a plate is not possible due to the lack of bone, transnasal canthopexy is typically required to stabilize the medial canthal tendon.
A 24-year-old man is brought to the emergency department one hour after he sustained injuries to the face and head in a motor vehicle collision. Physical examination shows a 5 × 1.5-cm laceration of the forehead, ecchymosis over the glabellar region, and watery nasal discharge. CT of the head shows a fracture of the frontal sinus. Which of the following findings on analysis of the nasal discharge confirms cerebrospinal rhinorrhea? (A)Alpha fetoprotein (B)Beta-2 transferrin (C)Glucose (D)Halo sign (E)Potassium
(B)Beta-2 transferrin
A 37-year-old woman is brought to the emergency department two hours after she sustained injuries to the face in a motor vehicle collision. Radiographs show an orbital zygomatic fracture on the left side. On ophthalmologic examination, the left pupil fails to constrict when direct light is shined in the eye; consensual pupillary constriction is normal. Color perception is diminished in the left eye. Findings in the right eye are normal. Which of the following is the most likely cause of these findings?
(A)Detachment of the retina
(B)Extension of the fracture through the optic canal
(C)Impingement of bone fragments on the optic (II) nerve
(D)Shear force injury to theoptic (II) nerve
(E)Thrombosis of the retinal artery
(D)Shear force injury to theoptic (II) nerve
Percent of patients w/ optic neuropathy after severe facial trauma
The finding of traumatic optic neuropathy has been reported in 2% to 5% of patients with severe facial trauma.
Where does shear force to the optic nerve happen
The dural sheath is firmly attached to the optic nerve at its entrance into the optic foramen.
Rapid deceleration injuries of the head can generate forces that are concentrated at the optic foramen.
A 38-year-old man sustains panfacial fractures in a motor vehicle collision. During surgical reduction, which of the following structures is most appropriate to restore the transverse dimension of the facial skeleton?
(A)Condyle and posterior mandibular ramus
(B)Mandibular arch
(C)Nasomaxillary buttress
(D)Pterygomaxillary buttress
(E)Zygomaticomaxillary buttress
(B)Mandibular arch
Vertical buttresses
Nasomaxillary
Zygomaticomaxillary Pterygomaxillary
The condyle and posterior mandibular ramus make up yet another buttress establishing posterior facial height.
Horizontal buttresses
Frontal
Zygomatic
Maxillary
Mandibular
What is the mandibular buttress composed of?
The mandibular arch
A 25-year-old man is brought to the emergency department 30 minutes after sustaining severe trauma to the head and face during a motor vehicle collision. Examination shows clear-fluid rhinorrhea, indicating leakage of cerebrospinal fluid. This patient has most likely sustained an injury to which ofthe following structures? (A)Anterior ethmoidal air cells (B)Cribriform plate (C)Frontonasal duct (D)Orbital portion of frontal bone (E)Superior nasal concha
(B)Cribriform plate
What is the cribriform plate comprised of?
The horizontal component of the ethmoid bone
Lateral masses of the ethmoid bone
he lateral masses of the ethmoid bone extend from the periphery of the cribriform plate, contain the anterior ethmoid air cells, and articulate with the orbital portion of the frontal bone
Crista galli
The crista galli is a midline prominence that serves as a point of attachment for intracranial soft tissue and that centers the cribriform plate.
A 20-year-old man who sustained a naso-orbital-ethmoid fracture undergoes transnasal wire canthopexy. Which of the following vectors, relative to the position of the insertion of the medial canthal tendon, is most appropriate for placement of the primary wire? (A)Anterior and inferior (B)Anterior and superior (C)Posterior and inferior (D)Posterior and superior
(D)Posterior and superior
The bony intercanthal distance should be:
The bony intercanthal distance should be between 16 and 23 mm
The 27-year-old woman shown above comes to the office for evaluation because she has had diplopia for the past 18 months. Physical examination shows orbital dystopia, enophthalmos, and malar flattening on the right. On the basis of the current findings, this patient’s prior injury was most likely which of the following fractures? (A)Le Fort II fracture (B)Le Fort III fracture (C)Orbital floor blow-out fracture (D)Orbital roof fracture (E)Orbitozygomatic complex fracture
(E)Orbitozygomatic complex fracture
Orbital floor or roof fractures would not result in malar flattening. Le Fort II and III fractures would cause a malocclusion, which is not present in this patient.
Clinical features typical for orbitozygomatic fractures
The clinical findings of orbital dystopia, enophthalmos, and malar flattening on the patient’s right side are typical for orbitozygomatic fractures.
With the downward pull of the muscles, the zygoma rotates and the orbital volume is increased. This results in enophthalmos and possible dystopia, depending on the degree of displacement.
A 7-year-old boy is brought to the emergency department after sustaining trauma to the face. He has nausea and vomiting but is alert and oriented to time and place. Pulse rate is 48/min. Physical examination shows right periorbital ecchymosis, diplopia, and limited vertical gaze. Visual acuity is within normal limits. Which of the following is the most likely finding on CT scan of the head and craniofacial skeleton?
(A)Compression of the optic nerve
(B)Displaced fracture of the zygoma
(C)Large (greater than 3 cm) displaced fracture of the orbital floor
(D)Minimally displaced fracture of the orbital floor
(D)Minimally displaced fracture of the orbital floor
Based on the patient’s age, signs, and symptoms, a CT scan is most likely to show a minimally displaced fracture of the orbital floor, suggesting a trapdoor fracture of the orbital floor.
A CT scan is not likely to show compression of the optic nerve because the patient does not have a relative afferent pupillary defect. A CT scan also is unlikely to show a displaced fracture of the zygoma because this type of fracture usually occurs in older patients. This study should not disclose a large displaced fracture of the orbital floor because this type of fracture does not typically cause oculocardiac reflex. Because the patient’s mental status is intact, a CT scan is not likely to show a subarachnoid hemorrhage.
Trapdoor orbital floor fracture on DT
A CT scan is most likely to show a minimally displaced fracture of the orbital floor.
This type of fracture allows herniation of the orbital contents, which are then entrapped.
In which patient population do trapdoor fractures most often occur?
These most commonly occur in children, possibly because of the relative elasticity of their bones, which allows them to snap back into position after tissue herniates through the fracture.
Oculocardiac reflex
A trapdoor fracture of the orbital floor can cause an oculocardiac reflex, which produces bradycardia, nausea, and syncope.
A 25-year-old man comes to the office because he has numbness of the tip of the nose six weeks after he sustained a naso-orbital-ethmoid fracture during a motor vehicle collision. The most likely cause of the numbness is damage to which of the following nerves? (A)Anterior ethmoidal (B)Infraorbital (C)Infratrochlear (D)Nasopalatine (E)Pterygopalatine
(A)Anterior ethmoidal
What nerve innervates the nasal tip?
The anterior ethmoidal nerve
What nerve supplies the upper and middle turbinates?
The lateral branch of the pterygopalatine nerve
What nerve innervates the septum?
The medial branch of the pterygopalatine nerve
What does the nasopalatine nerve innervate?
The nasopalatine nerve, which is the terminal branch of the pterygopalatine nerve, innervates the maxillary incisor teeth, gingiva, and palate
What is the terminal branch of the pterygopalatine nerve?
The nasopalatine nerve
In a patient with fracture of the frontal sinus, laboratory analysis of which of the following is most reliable to confirm cerebrospinal rhinorrhea? (A)Albumin (B)Beta-2 transferrin (C)Glucose (D)Glutamine (E)Lactic acid
(B)Beta-2 transferrin
Sensitivity / specificity of beta-2 transferrin
Sensitivity near 100% and a specificity near 95%
Cranialization is indicated for patients with which of the following conditions of the frontal sinus?
(A)Fracture of the anterior sinus wall
(B)Fracture of the nasofrontal duct
(C)Fracture of the posterior sinus wall
(D)Fracture of the sinus floor into orbital roof
(E)Post-traumatic frontal sinus mucocele
(C)Fracture of the posterior sinus wall
Although cranialization is indicated for fractures of the posterior sinus wall, not all frontal sinus fractures involving the posterior wall require cranialization. Exceptions would be noted in cases of undisplaced fracture in which the dura is deemed intact by clinical observation and confirmatory testing. Even in patients with leakage of cerebrospinal fluid (CSF), many surgeons will allow up to 10 days for the CSF leak to resolve on its own before resorting to cranialization, as long as all fractures are undisplaced and the nasofrontal duct is patent. In addition, cases of posterior wallfracture with obstructed nasofrontal ducts can be addressed with sinus obliteration and not cranialization, as long as there is no brain injury and little or no comminution of the posterior wall.
What posterior frontal sinus fractures don’t require cranialization?
Undisplaced fracture where the dura is deemed intact by clinical observation and confirmatory testing.
Even in patients with leakage of cerebrospinal fluid (CSF), many surgeons will allow up to 10 days for the CSF leak to resolve on its own before resorting to cranialization, as long as all fractures are undisplaced and the nasofrontal duct is patent.
Posterior wall frontal sinus fracture (no comminution) with obstructed nasofrontal ducts - treatment
Cases of posterior wall fracture with obstructed nasofrontal ducts can be addressed with sinus obliteration and not cranialization, as long as there is no brain injury and little or no comminution of the posterior wall.
How to determine source of CSF leak if it is not completely obvious
If there are other potential sources of a CSF leak, sortingout the cause can be done preoperatively with a metrizamide CT scan.
Management of an anterior table fracture with an intact posterior table and an intact frontonasal duct
Management of an anterior table fracture with an intact posterior table and an intact frontonasal duct should be addressed by plating the anterior table to restore forehead contour.
Frontal sinus fracture with obstruction of the nasofrontal duct: treatment
If the nasofrontal duct is obstructed, then obliteration of the frontal sinus is indicated.
Frontal sinus floor fracture medial to the supraorbital foramen
When the sinus floor is fractured medial to the supraorbital foramen, there is a good chance that the nasofrontal duct is injured, in which case sinus obliteration is indicated. If it is not injured, then plating is indicated to restore the orbital roof if fracture lines are displaced.
Management of post-traumatic frontal sinus mucocele
Post-traumatic mucoceles of the frontal sinus are managed by sinus obliteration. The exception is,however, that cranialization could be indicated in a few instances where the mucocele has become extremely expanded and destructive on the posterior table.
A 7-year-old boy is being evaluated after sustaining facial injuries when he fell while climbing playground equipment. Radiographs show a fracture of the orbit. Which of the following additional findings best supports urgent surgical repair in this patient? (A) Acute enophthalmos (B) Corneal abrasion (C) Diplopia on upward gaze (D) Entrapment of the rectus muscle (E) Hyphema
(D) Entrapment of the rectus muscle
Timing for repair of an orbital fracture
Most orbital fractures can be safely and effectively repaired. within two weeks. This allows periorbital edema to resolve and makes the dissection easier.
In the pediatric population, there is a subset of orbital fractures which require emergent repair: A trapdoor fracture refers to an orbital floor fracture that, because of the elastic recoil of cartilaginous bone, traps orbital contents and the inferior rectus muscle within the maxillary sinus.
