Regarding an orbital blowout fracture, which ONE of the following statements is TRUE?
Answer: B: Orbital blowout fracture occurs with blunt injury to the orbit (e.g. punch over the orbit). It is an isolated orbital floor or medial wall fracture. The fracture line does not extend to the orbital rim. The fracture opens up the ethmoid sinus through the medial wall, or maxillary sinus through the orbital floor. If it involves the ethmoid sinus, subcutaneous emphysema can develop, especially with sneezing. Herniation of the contents of the lower part of the orbital cavity may occur through the fracture into the maxillary sinus. The inferior rectus muscle can get physically entrapped in the fracture. Therefore the following clinical and radiological features may be present:
Enophthalmos
This fracture cannot be diagnosed using the facial X-ray views. However, the ‘tear drop’ sign on a facial X-ray, produced by the herniation of orbital contents into the maxillary sinus, and opacification or an air-fluid level in the maxillary sinus may indicate the presence of this fracture. CT is highly sensitive in the diagnosis.
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Regarding an orbital blowout fracture, which ONE of the following statements is CORRECT?
Answer: C: Urgent surgical repair is not indicated for an isolated orbital blowout fracture, even when it is associated with entrapment. Generally surgical repair is done electively when the swelling has subsided, usually around 7–10 days. However, during this time oral antibiotic treatment is indicated because of the communication with the paranasal sinuses.
Significant injury to the eye can occur with orbital blowout fractures. A complete examination of the eye with full dilatation of the pupil should be done at least as an outpatient to exclude: retinal tears and detachments; lens dislocations and subluxations; hyphaema; and corneal injuries. Retrobulbar haematoma and compressive orbital emphysema are important complications and should be recognized. These patients may represent with worsening severe eye pain, reduced vision and proptosis.
Regarding a patient presenting to the ED with a suspected retrobulbar haematoma following blunt trauma to the orbit, all of the following statements are true EXCEPT:
Answer: C: Patients might occasionally present to the ED with signs of retrobulbar haemorrhage following a severe degree of blunt trauma to the orbit. Patients on anticoagulant therapy may present in a similar way. The orbit can be an uncompromising soft tissue space due to the presence of the globe in the front and the firm attachments of the eyelids to the orbital rim with the lateral and medial canthal ligaments. As a result, undisplaced orbital fractures are more commonly associated with complications due to retrobulbar haemorrhage than displaced fractures. Increased intraocular pressure due to the tamponading effect in the orbital space can cause severe compression of the central retinal artery and optic nerve, and its blood supply. The resultant ischaemia of the retina and optic nerve causes visual loss. The symptoms are:
If there is no visual loss and there are signs of increased IOP, medical therapy (topical beta blockers and IV mannitol or acetazolamide) can be attempted to reduce the increased intraocular pressure until the patient is transferred for definitive ophthalmology care. In the presence of visual loss in a suspected case of retrobulbar haematoma lateral canthotomy is indicated emergently without waiting for a confirmatory CT scan. Although most clinicians do not have prior experience in this procedure in the correct setting, this is the only procedure that can save permanent loss of sight due to ischaemia. However, there should be enough clinical evidence to suggest there is vision-compromising retrobulbar haematoma. Complications and scarring caused by lateral canthotomy are limited and acceptable in such a patient.
Regarding the control of bleeding in posterior epistaxis, all of the following methods may be helpful EXCEPT:
Answer: C: The usual source for posterior nasal bleeds is the sphenopalatine artery, which is supplied by the external carotid arterial system. It cannot be seen through examining the anterior nose and requires nasoendoscopy or surgical exposure to visualize.
Posterior epistaxis is usually diagnosed late in the ED, often after failed attempts at controlling bleeding with direct pressure, use of vasoconstrictors and anterior nasal packing with balloon devices or nasal tampons. In addition, significant bleeding in the elderly and continuous bleeding into the nasopaharynx may indicate posterior bleeding. Thrombogenic foams and gels such as Gelfoam, Surgicel and Floseal can be convenient and effective in controlling anterior bleeds but cannot be used to control posterior bleeds.
Transpalatal injection of a local anaesthetic or vasoconstrictor solution (2 mL of 1% lignocaine with adrenaline) close to the sphenopalatine artery may help to reduce significant posterior bleeds. This can be achieved by inserting a 25-gauge needle, bent at 2.5 cm from the tip, through the descending palatine foramen just medial to the upper second molar tooth.
Posterior nasal packs stop posterior epistaxis in approximately 70% of patients. Endoscopic surgical ligation or embolization is used to control bleeding once posterior nasal packing has failed. The success rate for surgical ligation of the sphenopalatine artery is reported to be equal or better than the success rate for embolization, which is 80–90%.
Regarding a patient presenting to the ED with epistaxis, which ONE of the following statements is TRUE?
Answer: D: About 90% of epistaxis are anterior and 10% are posterior. Posterior epistaxis is most common in elderly patients. Although hypertension is often seen in patients who present to the ED with epistaxis, the association has not been proven. Often anxiety may elevate BP and therefore rapid reduction of elevated blood pressure (BP) is not recommended. Gentle reduction in BP may be helpful to allow clot formation. Once clots have been removed, and local vasoconstrictor solution and direct pressure have been applied, chemical cautery with silver nitrate sticks can be attempted to control a visualized anterior bleed. Chemical cautery should only be attempted on one side of the nasal septum and even a second attempt on the same side should be avoided for 4–6 weeks to prevent perforation of the septum.
When the balloon of a Foley catheter is used to control a posterior bleed, the balloon should be inflated with saline up to a volume of about 15 mL (not 30 mL) to prevent pressure necrosis. The balloon device should then be retracted anteriorly to provide the tamponade in the choanae and sphenopalatine foramen areas.
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