Orbital floor fracture with entrapment: Imaging and clinical correlations in 45 cases

Abstract

Orbital floor fractures (OFF) with entrapment require prompt clinical and radiographic recognition for timely surgical correction. Correct CT radiographic interpretation of entrapped fractures can be subtle and thus missed. We reviewed the clinical, radiographic and intraoperative findings of 45 cases of entrapped OFF to correlate pre- and intraoperative findings with radiography. Retrospective review and statistical analysis of 45 patients with OFF using the chi squared and Kruskal-Wallis tests. Main outcome measures included patient demographics, clinical features, radiologic interpretation, intraoperative findings, and treatment outcomes. Twenty-one cases (47%) had radiologic evaluations of orbital CT scans that included commentary on possible entrapment. Intraoperatively, 16 (76%) of these patients had the inferior rectus muscle incarcerated in the fracture, while 5 (24%) patients had incarceration of the orbital fat. Possibility of entrapment was not commented on in the radiology reports of the remaining 24 (53%) cases. Intraoperatively, 13 (54%) of these patients had the inferior rectus muscle incarcerated in the fracture, while 11 (46%) patients had incarceration of the orbital fat. It is vital to assess the possibility of entrapment, especially in young patients, in the setting of OFF as a delay in diagnosis may lead to persistent diplopia, disfigurement, or bradycardia. Most radiology reports did not mention the possibility of entrapment in this cohort. A key concept is that entrapment occurs when any orbital tissue (muscle or fat) is trapped in the fracture site.

Is Surgery Needed for Diplopia after Blowout Fractures? A Clarified Algorithm to Assist Decision-making

“…1,23 If evidence of muscle extrusion is observed on CT, vertical diplopia while gazing downward may occur and surgery should be considered. 5,8,24 Posttraumatic inflammation, whether being presurgery or postsurgery, and the subsequent formation of scars and fibrosis at inferior periorbital tissue sites might produce adhesions and thus restrict normal movement of the EOM when the eyeballs gaze downward. 1,23,[25][26][27] When there is no abnormality regarding motility, the algorithm continues to the aspect of position (Fig.…”

Adult Strabismus Preferred Practice Pattern®

“…Significant fat or periorbital tissue entrapment can also result in permanent strabismus in the absence of muscle entrapment. 192 o Large floor fractures, hypoglobus, and progressive infraorbital hypoesthesia are also best addressed within about 2 weeks.…”

“…Fat entrapment can prove nearly as challenging as extraocular muscle entrapment, resulting in fibrotic and adhesion syndromes not readily relieved with dissection around the involved muscle. 192 Adhesions and entrapment may extend well into the deeper orbit, out of reach of the strabismus surgeon.…”

Computed tomography in traumatic orbital emergencies: a pictorial essay—imaging findings, tips, and report flowchart

“…A particular type of orbital floor BOFs is represented by the trapdoor fracture, which usually occurs in children and toddlers due to the distensibility of immature facial bones [ 19 ]. In this type of fracture, the inferior rectus muscle and/or intraorbital fat prolapse through the fracture defect into the underlying maxillary sinus, and the fracture bony fragment springs back into place, acting like a trapdoor.…”