Abstract

Introduction

Orbital emphysema usually resolves spontaneously without consequence. In extreme cases, compartment syndrome may develop. These rare cases may require intervention to prevent permanent vision loss.[¹] Although orbital emphysema is most often seen after trauma, it can be encountered in a number of settings. Examples include gas-producing infections, compressed air injury (e.g., with pneumatically cooled dental drills or industrial accidents), and other iatrogenic surgical trauma.[^2,3,4,5] In this report, we present a case of orbital emphysema presenting several days after placement of a zygomatic denture-anchoring implant. This case report is compliant with the Health Insurance Portability and Accountability Act.

Case Report

A 79-year-old man with a history of hyperlipidemia, atrial fibrillation, Parkinson's disease, hepatitis, and peripheral vascular disease awoke with acute-onset swelling around the left eye and cheek [Figure 1]. Six days prior, he had undergone replacement of loose mandibular denture-anchoring implants with a zygomatic implant [Figure 2]. This type of implant has been in use since the 1990s for patients with maxillary atrophy, and placement often involves creating a window in the anterior maxilla.[⁶] He had not taken the prescribed postoperative antibiotics. He denied systemic symptoms, trauma, or other events related to the onset of swelling. Specifically, he did not recall sneezing or blowing his nose and did not wear any airway device. The swelling was painless and did not progress over the course of the day. He went to an urgent care clinic and was referred to the ophthalmology office.

Open in a separate window

Figure 1

Clinical presentation (a) front view and (b) from below

Open in a separate window

Figure 2

Computed tomography findings show orbital emphysema in (a) coronal and (b) axial views, as well as the iatrogenic defect in the maxillary bone (solid arrow) in coronal (c) and axial (d) views, and scout images depicting the orientation of the dental implants (outline arrowheads) in coronal (e) and sagittal (f) views

On evaluation, marked periocular and facial swelling was easily appreciated. Palpation of the involved area revealed crepitus consistent with subcutaneous emphysema, and there was 2.5-mm relative proptosis by the Hertel exophthalmometry. There was no other evidence of infectious cellulitis: the involved area was not erythematous, warm, or tender. The remainder of the evaluation was normal. Visual acuity measured 20/30 OU, consistent with lens clarity, and intraocular pressure measured 14 and 12 mmHg in the right and left eyes, respectively. Pupils were symmetric and briskly responsive to light with no relative afferent pupillary defect. He was orthophoric with normal extraocular movement. Computed tomography confirmed the presence of subcutaneous air extending into the left periocular area and orbit. A defect in the left maxillary wall adjacent to the dental implant was visualized [Figure 2].

As there were no signs clinically or radiographically to suggest infection, he was observed closely. The subcutaneous emphysema and proptosis resolved spontaneously with time.

Discussion

Various orbital complications have been reported with dental conditions and procedures. The majority of these cases are infectious, with dental abscesses spreading to cause orbital cellulitis.[⁷] Direct violation of the orbit has also been reported with the zygomatic implant procedure, although there were no sequelae in that case.[⁷] Although subcutaneous emphysema and orbital emphysema are uncommon complications of dental procedures, they have been described outside of the ophthalmic literature. A systematic review in 2009 reported orbital involvement in 18 of 32 cases of subcutaneous emphysema after oral surgical procedures.[⁵] Onset in these previous descriptions is uniformly within 24 h of surgery. To our knowledge, this is the first description of orbital emphysema occurring days following a dental procedure in the absence of a known sneeze or other Valsalva maneuver. We suspect, however, some positive-pressure events in combination with the still-healing mucosa and bony defects in the maxillary sinus wall allowed air to dissect along tissue planes of the face to reach the anterior left orbit and periorbital tissues.

Although usually self-limited and without sequelae, orbital emphysema has been associated with vision loss. In 1994, Hunts et al. proposed a 4-stage classification for orbital emphysema, ranging from no effect on globe position and vision (Stage I) to proptosis with intraocular pressure elevation enough to induce a central retinal artery occlusion (Stage IV).[¹] When optic nerve compression is encountered, decompression can be accomplished in the clinic with simple needle aspiration of air.[¹] Because of this potential for orbital compartment syndrome, knowledge and prompt recognition of this possible complication of dental surgery are essential. This case is important as it illustrates the potential for orbital emphysema to develop days following dental procedures, without recollection of a Valsalva event. This clinical scenario mimics infection. Orbital imaging is a key to distinguishing orbital emphysema from infection when there is no clear history of a Valsalva event, allowing for appropriate intervention and avoidance of unnecessary antibiotics.

References