Blowout fracture | |
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Other names | Orbital floor fracture |
An orbital blowout fracture of the floor of the left orbit. | |
Specialty | Oral & Maxillofacial Surgery, ENT surgery, plastic surgery, ophthalmology |
Symptoms | Double vision especially when looking up, numbness of the lateral nose skin, the cheek below the eyelid, and the upper lip, Bloody nose, lateral subconjunctival hemorrhage (bright red blood over the sclera (white of the eye)) |
Causes | Direct trauma to the eye socket. |
An orbital blowout fracture is a traumatic deformity of the orbital floor or medial wall that typically results from the impact of a blunt object larger than the orbital aperture, or eye socket. [1] Most commonly this results in a herniation of orbital contents through the orbital fractures. [1] The proximity of maxillary and ethmoidal sinus increases the susceptibility of the floor and medial wall for the orbital blowout fracture in these anatomical sites. [2] Most commonly, the inferior orbital wall, or the floor, is likely to collapse, because the bones of the roof and lateral walls are robust. [2] Although the bone forming the medial wall is the thinnest, it is buttressed by the bone separating the ethmoidal air cells. [2] The comparatively thin bone of the floor of the orbit and roof of the maxillary sinus has no support and so the inferior wall collapses mostly. Therefore, medial wall blowout fractures are the second-most common, and superior wall, or roof and lateral wall, blowout fractures are uncommon and rare, respectively. They are characterized by double vision, sunken ocular globes, and loss of sensation of the cheek and upper gums from infraorbital nerve injury. [3]
The two broad categories of blowout fractures are open door and trapdoor fractures. Open door fractures are large, displaced and comminuted, and trapdoor fractures are linear, hinged, and minimally displaced. [4] The hinged orbital blowout fracture is a fracture with an edge of the fractured bone attached on either side. [5]
In pure orbital blowout fractures, the orbital rim (the most anterior bony margin of the orbit) is preserved, but with impure fractures, the orbital rim is also injured. With the trapdoor variant, there is a high frequency of extra-ocular muscle entrapment despite minimal signs of external trauma, a phenomenon that is referred to as a "white-eyed" orbital blowout fracture. [3] The fractures can occur of pure floor, pure medial wall or combined floor and medial wall. They can occur with other injuries such as transfacial Le Fort fractures or zygomaticomaxillary complex fractures. The most common causes are assault and motor vehicle accidents. In children, the trapdoor subtype are more common. [6] Smaller fractures are associated with a higher risk of entrapment of the nerve and therefore often smaller fracture are more serious injuries. Large orbital floor fractures have less chance of restrictive strabismus due to nerve entrapment but a greater chance of enopthalmus.
There are a lot of controversies in the management of orbital fractures. the controversies debate on the topics of timing of surgery, indications for surgery, and surgical approach used. [4] Surgical intervention may be required to prevent diplopia and enophthalmos. Patients not experiencing enophthalmos or diplopia and having good extraocular mobility may be closely followed by ophthalmology without surgery. [7]
Some clinically observed signs and symptoms include: [8] [9]
Common medical causes of blowout fracture may include: [10]
There are two prevailing theories to how orbital fractures occur. The first theory is the hydraulic theory. The hydraulic theory states that a force is applied to the globe which results in equatorial expansion of the globe due to increasing hydrostatic pressure. [10] The pressure is eventually released at the weaker point in the orbit (the medial and inferior walls). Theoretically, this mechanism should lead to more fractures of the medial wall than the floor, since the medial wall is slightly thinner (0.25 mm vs 0.50 mm). [12] However, it is known that pure blowout fractures most frequently involve the orbital floor. This may be attributed to the honeycomb structure of the numerous bony septa of the ethmoid sinuses, which support the lamina papyracea, thus allowing it to withstand the sudden rise in intraorbital hydraulic pressure better than the orbital floor. [13]
The second prevailing theory is known as the buckling theory. The buckling theory states that a force is transmitted directly to the facial skeleton and then a ripple effect is transmitted to the orbit and causes buckling at the weakest points as described above. [10]
In children, the flexibility of the actively developing floor of the orbit fractures in a linear pattern that snaps backward. This is commonly referred to as a trapdoor fracture. [7] The trapdoor can entrap soft-tissue contents, thus causing permanent structural change that requires surgical intervention. [7]
Diagnosis is based on clinical and radiographic evidence. Periorbital bruising and subconjunctival hemorrhage are indirect signs of a possible fracture.[ citation needed ]
The bony orbital anatomy is composed of 7 bones: the maxillary, zygomatic, frontal, lacrimal, sphenoid, palatine, and ethmoidal. [14] The floor of the orbit is the roof of the maxillary sinus. [15] The medial wall of the orbit is the lateral wall of the ethmoid sinus. The medial wall is also known as the lamina papyrcea which means "paper layer." This demonstrates the thinness which is associated with increased fractures. [14] The clinically important structures surrounding the orbit include the optic nerve at the apex of the orbit as well as the superior orbital fissure which contains cranial nerves 3, 4, and 6 therefore controlling ocular muscles of eye movement. [15] Inferior to the orbit is the infraorbital nerve which is purely sensory. Five cranial nerves (optic, oculomotor, trochlear, trigeminal, and abducens), and several vascular bundles, pass through the orbital socket. [14]
Thin cut (2-3mm) CT scan with axial and coronal view is the optimal study of choice for orbital fractures. [16] [17]
Plain radiographs, on the other hand, do not have the sensitively capture blowout fractures. [18] On Water's view radiograph, polypoid mass can be observed hanging from the floor into the maxillary antrum, classically known as teardrop sign, as it usually is in shape of a teardrop. This polypoid mass consists of herniated orbital contents, periorbital fat and inferior rectus muscle. The affected sinus is partially opacified on radiograph. Air-fluid level in maxillary sinus may sometimes be seen due to presence of blood. Lucency in orbits (on a radiograph) usually indicate orbital emphysema. [4]
All patients should follow-up with an ophthalmologist within 1 week of the fracture. To prevent orbital emphysema, patients are advised to avoid blowing of the nose. [16] Nasal decongestants are commonly used. It is also common practice to administer prophylactic antibiotics when the fracture enters a sinus, although this practice is largely anecdotal. [8] [19] Amoxicillin-clavulanate and azithromycin are most commonly used. [8] Oral corticosteroids are used to decrease swelling. [20]
Surgery is indicated if there is enophthalmos greater than 2 mm on imaging, Double vision on primary or inferior gaze, entrapment of extraocular muscles, or the fracture involves greater than 50% of the orbital floor. [8] When not surgically repaired, most blowout fractures heal spontaneously without significant consequence. [21]
Surgical repair of a "blowout" is rarely undertaken immediately; it can be safely postponed for up to two weeks, if necessary, to let the swelling subside. Surgery to treat the fracture generally leaves little or no scarring and the recovery period is usually brief. Ideally, the surgery will provide a permanent cure, but sometimes it provides only partial relief from double vision or a sunken eye. [22] Reconstruction is usually performed with a titanium mesh or porous polyethylene through a transconjunctival or subciliary incision. More recently, there has been success with endoscopic, or minimally invasive, approaches. [23]
1. Transcutaneous Transcutaneous surgery can be performed from a variety of surgical incisions. [24] The first is known as the infraciliary incision. [25] This incision has an advantage as the scar is barely perceivable but the disadvantage is that there is a higher rate of ectropion after repair. [26] The next incision can be performed at the lower eyelid crease also known as the sub tarsal. This creates a more visible scar but has a lower risk of ectropion. [25] The final incision option is infraorbital which allows the easiest access to the orbit but results in the most visible scar. [25]
2. Transconjunctival The advantage to this approach is direct access to the orbit and there is no skin incision. [25] The disadvantage to this a purported decreased view of the orbit which can be offset with a canthotomy to increase the view of the orbit. [26]
3. Endosocpic Approaches Endoscopically, transnasal and transantral approaches had been used for reduction and support of fractured medial and inferior walls, respectively enophthalmos was improved in 89% of the endoscopic group and 76% of the external group (NS). [25] The endoscopic group had no significant complications. [27] The external group had ectropions, significant facial scars, extrusion of inserted Medpor, and intra-orbital hematoma.Disadvantage is working towards the globe rather than away with instruments. [28]
Orbital fractures, in general, are more prevalent in men than women. In one study in children, 81% of cases were boys (mean age 12.5 years). [29] In another study in adults, men accounted for 72% of orbital fractures (mean age 81). [30] It has also been shown in the literature that put orbital medial wall fractures are more common in African Americans due to the increased density of their bone minerals compared to other ethnicities. However the lamina papyrcea is the same in all ethnicities so this is more commonly broken in African Americans
Orbital floor fractures were investigated and described by MacKenzie in Paris in 1844 [17] and the term blow out fracture was coined in 1957 by Smith & Regan, [31] who were investigating injuries to the orbit and resultant inferior rectus entrapment, by placing a hurling ball on cadaverous orbits and striking it with a mallet.In the 1970s an occuplastic surgeon named Putterman described the first recommendations for surgery. In the 1970s Putterman advocated for repair of virtually no orbital floor fractures and instead promoted watchful waiting for up to six weeks. At the same time the Plastic surgeons put out literature recommending repair of every orbital floor fracture. Now there has been a softening from both sides and an agreeance in the middle.
The nasal cavity is a large, air-filled space above and behind the nose in the middle of the face. The nasal septum divides the cavity into two cavities, also known as fossae. Each cavity is the continuation of one of the two nostrils. The nasal cavity is the uppermost part of the respiratory system and provides the nasal passage for inhaled air from the nostrils to the nasopharynx and rest of the respiratory tract.
In anatomy, the orbit is the cavity or socket/hole of the skull in which the eye and its appendages are situated. "Orbit" can refer to the bony socket, or it can also be used to imply the contents. In the adult human, the volume of the orbit is 30 millilitres, of which the eye occupies 6.5 ml. The orbital contents comprise the eye, the orbital and retrobulbar fascia, extraocular muscles, cranial nerves II, III, IV, V, and VI, blood vessels, fat, the lacrimal gland with its sac and duct, the eyelids, medial and lateral palpebral ligaments, cheek ligaments, the suspensory ligament, septum, ciliary ganglion and short ciliary nerves.
Eye surgery, also known as ophthalmic surgery or ocular surgery, is surgery performed on the eye or its adnexa. Eye surgery is part of ophthalmology and is performed by an ophthalmologist or eye surgeon. The eye is a fragile organ, and requires due care before, during, and after a surgical procedure to minimize or prevent further damage. An eye surgeon is responsible for selecting the appropriate surgical procedure for the patient, and for taking the necessary safety precautions. Mentions of eye surgery can be found in several ancient texts dating back as early as 1800 BC, with cataract treatment starting in the fifth century BC. It continues to be a widely practiced class of surgery, with various techniques having been developed for treating eye problems.
The medial rectus muscle is a muscle in the orbit near the eye. It is one of the extraocular muscles. It originates from the common tendinous ring, and inserts into the anteromedial surface of the eye. It is supplied by the inferior division of the oculomotor nerve (III). It rotates the eye medially (adduction).
The superior orbital fissure is a foramen or cleft of the skull between the lesser and greater wings of the sphenoid bone. It gives passage to multiple structures, including the oculomotor nerve, trochlear nerve, ophthalmic nerve, abducens nerve, ophthalmic veins, and sympathetic fibres from the cavernous plexus.
The pyramid-shaped maxillary sinus is the largest of the paranasal sinuses, located in the maxilla. It drains into the middle meatus of the nose through the semilunar hiatus. It is located to the side of the nasal cavity, and below the orbit.
The ethmoid sinuses or ethmoid air cells of the ethmoid bone are one of the four paired paranasal sinuses. Unlike the other three pairs of paranasal sinuses which consist of one or two large cavities, the ethmoidal sinuses entail a number of small air-filled cavities. The cells are located within the lateral mass (labyrinth) of each ethmoid bone and are variable in both size and number. The cells are grouped into anterior, middle, and posterior groups; the groups differ in their drainage modalities, though all ultimately drain into either the superior or the middle nasal meatus of the lateral wall of the nasal cavity.
The cavernous sinus within the human head is one of the dural venous sinuses creating a cavity called the lateral sellar compartment bordered by the temporal bone of the skull and the sphenoid bone, lateral to the sella turcica.
Enophthalmos is a posterior displacement of the eyeball within the orbit. It is due to either enlargement of the bony orbit and/or reduction of the orbital content, this in relation to each other.
Silent sinus syndrome is a spontaneous, asymptomatic collapse of an air sinus associated with negative sinus pressures. It can cause painless facial asymmetry, diplopia and enophthalmos. Diagnosis is suspected based on symptoms, and can be confirmed using a CT scan. Treatment is surgical involving making an outlet for mucous drainage from the obstructed sinus, and, in some cases, paired with reconstruction of the orbital floor. It is slightly more common in middle age.
Functional endoscopic sinus surgery (FESS) is a procedure that is used to treat sinusitis and other conditions that affect the sinuses. Sinusitis is an inflammation of the sinuses that can cause symptoms such as congestion, headaches, and difficulty breathing through the nose.
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The Le Fortfractures are a pattern of midface fractures originally described by the French surgeon, René Le Fort, in the early 1900s. He described three distinct fracture patterns. Although not always applicable to modern-day facial fractures, the Le Fort type fracture classification is still utilized today by medical providers to aid in describing facial trauma for communication, documentation, and surgical planning. Several surgical techniques have been established for facial reconstruction following Le Fort fractures, including maxillomandibular fixation (MMF) and open reduction and internal fixation (ORIF). The main goal of any surgical intervention is to re-establish occlusion, or the alignment of upper and lower teeth, to ensure the patient is able to eat. Complications following Le Fort fractures rely on the anatomical structures affected by the inciding injury.
Endoscopic endonasal surgery is a minimally invasive technique used mainly in neurosurgery and otolaryngology. A neurosurgeon or an otolaryngologist, using an endoscope that is entered through the nose, fixes or removes brain defects or tumors in the anterior skull base. Normally an otolaryngologist performs the initial stage of surgery through the nasal cavity and sphenoid bone; a neurosurgeon performs the rest of the surgery involving drilling into any cavities containing a neural organ such as the pituitary gland. The use of endoscope was first introduced in Transsphenoidal Pituitary Surgery by R Jankowsky, J Auque, C Simon et al. in 1992 G.
Antral lavage is a largely obsolete surgical procedure in which a cannula is inserted into the maxillary sinus via the inferior meatus to allow irrigation and drainage of the sinus. It is also called proof puncture, as the presence of an infection can be proven during the procedure. Upon presence of infection, it can be considered as therapeutic puncture. Often, multiple repeated lavages are subsequently required to allow for full washout of infection.
Caldwell-Luc surgery, Caldwell-Luc operation, also known as Caldwell-Luc antrostomy, and Radical antrostomy, is an operation to remove irreversibly damaged mucosa of the maxillary sinus. It is done when maxillary sinusitis is not cured by medication or other non-invasive technique. The approach is mainly from the anterior wall of the maxilla bone. It was introduced by George Caldwell (1893)and Henry Luc (1897). The maxillary sinus is entered from two separate openings, one in the canine fossa to gain access to the antrum and other in the naso antral wall for drainage.
Frontal sinus trephination is a surgical procedure wherein a small opening is made in the floor of the frontal sinus to facilitate drainage of its contents. Drainage of the frontal sinus is done through the floor of frontal sinus above the inner canthus.
Orbital emphysema is a medical condition that refers to the trapping of air within the loose subcutaneous around the orbit that is generally characterized by sudden onset swelling and bruising at the impacted eye, with or without deterioration of vision, which the severity depends on the density of air trapped under the orbital soft tissue spaces.
Nasal surgery is a medical procedure designed to treat various conditions that cause nasal blockages in the upper respiratory tract, for example nasal polyps, inferior turbinate hypertrophy, and chronic rhinosinusitis. It encompasses several types of techniques, including rhinoplasty, septoplasty, sinus surgery, and turbinoplasty, each with its respective postoperative treatments. Furthermore, nasal surgery is also conducted for cosmetic purposes. While there are potential risks and complications associated, the advancement of medical instruments and enhanced surgical skills have helped mitigate them.
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