Endoscopic management of orbital and frontal sinus fractures.

Endoscopy is not a new concept to medicine. It is, however, relatively new to the field of craniomaxillofacial surgery. The first endoscope was introduced in 1805 and was used to visualize the bladder.1 Use of endoscopes was such a help to diagnosis and treatment that very quickly additional scopes were developed and used to visualize the cervix and the larynx. These scopes, however, were limited because light sources were poor and often internal. They produced a great deal of heat and could burn the tissues surveyed. It wasn't until Harold Hopkins developed the glass rod endoscope in 1966 (which bears his name) that the modern era of bright, cold light began.2 The “Hopkins rod” replaced the thin, fragile rod with glass ends with a more durable glass tube that had intervening air spaces. The newer design provided a clearer, brighter view and was more durable than the previous endoscopes. Although gynecologists, orthopedists, and other surgeons quickly adapted to these devices and used them in every real and virtual space in the body, maxillofacial surgeons rarely used them. There are no preformed cavities in the head and neck, other than the inside of the sinuses and pharynx, which are mainly the concern of the otolaryngologist. It was not until the 1990s that endoscopic sinus surgery techniques entered maxillofacial surgery. The techniques used were modifications (1) of plastic surgery techniques for brow lifting and (2) of otolaryngology techniques for sinus surgery. The instrumentation is virtually identical. These techniques were first used for endoscopic subcondylar repair3 and are now also used for transantral orbital floor reconstruction, zygomatic arch, and frontal sinus repair. Subcondylar fractures are difficult to treat openly in even the best of circumstances, and seeing and treating the condyle in its native position has numerous advantages. Once this use became more common, other facial fractures began to be examined from an endoscopic perspective. Fractures of the frontal sinus and orbit are relatively common in facial trauma patients (5 to 15% of all maxillofacial trauma).4 Although a significant percentage of these fractures can be managed nonoperatively, operative intervention is often required to avoid late complications. Some of the more typical complications of orbital fractures are diplopia from muscle entrapment, visual loss, and enophthalmos from volume expansion into the surrounding sinus leading to pseudoptosis. The typical complications from frontal sinus injuries are much less common but much more significant when encountered. These include frontal contour irregularities, spinal fluid leak (possibly resulting in meningitis), ocular complications including vision loss and blindness, and the late complication of mucocele. Surgeons in general weigh the risk of an operation and its approach against the benefits of preventing complications, and recommend surgery based on this analysis. In general, if a procedure has a lower risk of complications, it is more widely applied. Endoscopic techniques may provide lower rates of complications and higher acceptance rates in patients, and, therefore, they may be more widely employed. Because these techniques are very detailed and have a steep “learning curve,” surgeons should be patient in their evaluation and use. The risks of the surgical access approach for orbital procedures can infrequently be more significant than the complications of the fracture. Any transcutaneous approach can result in poor scaring that leads to ectropion and to poor lower lid position.5 In its most serious form, the poor lid position could cause dry eye, tearing, corneal ulceration, and corneal scarring with resulting loss of vision. Lid malposition occurs in 5 to 10% of postoperative patients.6 This may result in a poorer outcome than if the surgeon had just left the fracture alone. For this reason, approaches that avoid skin incisions have been devised. Transconjunctival incisions have the advantage of greatly limiting ectropion. They do, however, require that most of the postinjury swelling has disappeared. These approaches can cause muscle injury or entropion—a difficult complication to manage. These complications are much less frequent than the complications of the transcutaneous approach, but much more significant. A prominent oculoplastic surgeon has led me to believe that entropion is one of the most difficult situations to correct in lid surgery (N. Illiff, M.D., Johns Hopkins Hospital, personal communication). The risks of the approach in frontal sinus surgery are less significant than those that may occur in lower eyelid surgery, and most patients with frontal sinus injuries are operated on to prevent contour irregularities and to eliminate sinus outflow tract obstruction. However, the price these patients pay in the location and appearance of the incision line is great. There is also a small, but present risk to the frontal branch of the facial nerve.4 Patients that present with thinning hair or who keep their hair very short or shaved often would accept a small depression in the lower forehead over a 10-inch coronal scar across the top of the head. As surgeons, we must always be aware of the “fourth dimension” of surgery and realize that some patients who undergo coronal incisions at a young age will come to lose their hair later in life. For this reason, every surgeon should try to shorten or minimize surgical scars. Unicoronal incisions give poor exposure and frequently have to be extended toward the upper forehead to provide exposure of the relevant anatomy. Addition of the stealth incision (zigzag) actually increases the length of scar and can camouflage the scar if, and only if, the patient has hair.7 Extension of the coronal scar behind the ear is an excellent way to prevent the visible scar on the face. Rarely does one need this for non–skull base exposures. The final way to limit the scar is the use of the endoscope to aid in visualization. This is technology that has been used for years in the treatment of the upper third aging face. This essentially decreases the need for incisions to two or three 1-inch incisions, limiting the scar by 70 to 80%. The downside is that in most cases a small counter incision at the brow level is needed to manipulate the fracture and place the plates and screws. These are acceptable scars and heal with minimal scarring. The approval by the U.S. Food and Drug Administration (FDA) of a right-angled drill and screwdriver by Synthes (Brandywine, PA) may make the counter incision unnecessary in some cases. This article reviews the current literature and provides an outline for the management we are currently using at the Johns Hopkins Hospital for application of these techniques in our management of these patients. These techniques don't eliminate current standard approaches, but they extend the ability of the surgeon to offer minimal morbidity with maximal outcome. These techniques are typically employed in patients with fractures that are either limited or would not have previously been repaired—in the case of the frontal sinus fracture—due to patient nonacceptance of the coronal incision, or would not have been repaired due to the limited nature of the orbital floor fractures and increased morbidity of lid incisions.