Postoperative Imaging Appearance of Iliac Crest Free Flaps Used for Palatomaxillary Reconstructions

Abstract

The osteomyocutaneous iliac crest free flap is a reconstructive option for segmental mandibular or complex palatomaxillary defects. Familiarity with the radiographic appearance of free flaps such as the iliac crest is necessary for the postoperative evaluation of patients after mandibular, maxillary, or palatal reconstructions because it allows radiologists to properly monitor and interpret the appearance of the flap over time. This study presents a retrospective review of 5 patients who underwent palatomaxillary reconstruction with an iliac crest free flap at our institution. The imaging appearances of the 5 patients were analyzed to determine the key radiographic characteristics of a healthy and successful iliac crest free flap. Radiographic fluency with the imaging appearance of the iliac crest free flap, as well as the new anatomy of the region in the postoperative period, will allow for better interpretation of the flap appearance on imaging and will prevent false identification of tumor recurrence.

FIG 1.

Use of ICFF with internal oblique muscle (A) and orbital floor plate. The iliac bone is used to restore the inferior orbital rim as well as to reconstruct the pyriform aperture. An onlay bone graft is lag screwed into the iliac bone to restore the anterior projection of the midface (B and C). The curvature of the neomaxilla has been created by performing a unicortical osteotomy and filling it with corticocancellous bone followed by a fixation plate to hold it in position. The internal oblique muscle is used to reline the lateral wall of the nose and obliterate the maxillectomy cavity (D and E). The muscle is transposed through the palatal defect to achieve a permanent separation of the mouth from the sinonasal cavity. Illustration by Jill Gregory. Used with permission from ^©Mount Sinai Health System.

FIG 2.

The internal oblique muscle from the flap eliminates the maxillectomy cavity, thereby preventing the presence of dead space (arrows).

FIG 3.

A, An iliac crest–internal oblique flap has been harvested based on the DCIA and DCIV (asterisk). B, The iliac crest is shown inset into a palatomaxillectomy defect with the crest oriented toward the bottom (arrow). The internal oblique muscle based on the ascending branch of the DCIA has been brought through the palatal defect, medial to the iliac bone (curved arrow). This patient underwent an orbital exenteration, and the internal oblique muscle (IOM) is shown filling the orbital defect as well as obliterating the maxillectomy cavity. Rigid fixation (RF) is achieved to the lateral and superior orbital rim. The upgoing arrow shows a dental implant placed into the neoalveolar ridge. C, The internal oblique muscle, which is not optimally visualized on bone window, is used to fill the maxillectomy defect (arrow).

FIG 4.

Axial imaging of a normal ICFF demonstrating a thick sheet of bone with a hyperattenuated cortex and intermediate attenuation of the trabecular surface. An osteotomy site is demonstrated and filled with corticocancellous bone (arrow). Images were obtained in the immediate postoperative period. Left cheek prominence is an expected immediate postoperative finding in the flap setting. Normal cheek cosmesis will be obtained over time.

FIG 5.

Normal appearance of reconstructive plates and osseointegrated dental implants (arrow).