What is the recommended management for a patient undergoing an orbital plate preserving maxillectomy?

Orbital Plate Preserving Maxillectomy: Management Recommendations

For patients undergoing orbital plate preserving maxillectomy, perform comprehensive preoperative imaging with three-dimensional CT to identify anatomical variations, ensure adequate antibiotic prophylaxis, and plan for immediate reconstruction using either myocutaneous or osteomyocutaneous free flaps for defects larger than 2.5 cm, with titanium mesh and fascia lata as an alternative when microvascular resources are unavailable. 1, 2

Preoperative Planning

Essential Imaging and Consultation

• Obtain cone beam CT or conventional CT extended to the orbit to visualize the osteomeatal complex, identify sinus septa (present in ~30% of patients), and assess anatomical variations that will impact surgical approach 3, 1
• Request otorhinolaryngology consultation if the patient has any history of sinusitis, nasal obstruction, chronic respiratory disease, or radiologic evidence of mucosal thickening >3mm with osteomeatal complex closure 3, 1
• Review radiation therapy plans if the patient has prior head and neck radiation, paying particular attention to cumulative dose to the maxilla, as doses ≥50 Gy significantly increase osteoradionecrosis (ORN) risk 3

Medical Optimization

• Administer prophylactic antibiotics perioperatively; recommended regimens include amoxicillin 500mg TID for 7-10 days or clindamycin 300mg TID for 10 days in penicillin-allergic patients 1, 4
• For patients with prior radiation ≥50 Gy to the maxilla, prescribe pentoxifylline 400mg twice daily plus tocopherol 1,000 IU once daily starting at least 1 week preoperatively and continuing 4 weeks postoperatively to reduce ORN risk 3
• Complete all necessary dental extractions at least 2 weeks before surgery when feasible, though oncologic timing takes priority over healing intervals 3

Surgical Technique

Access and Exposure

• Create a Weber-Ferguson incision with extensions based on tumor extent for adequate visualization, or use a midface degloving approach to reduce hardware extrusion risk in patients requiring postoperative radiation 1, 5
• Elevate complete mucoperiosteal flaps to visualize the lateral maxillary wall and zygomaticomaxillary buttress 1
• Position the access window near the zygomatic process to optimize surgical access while preserving the orbital floor 1

Resection Principles

• Perform en bloc resection whenever technically feasible with clear margins of at least 1.5-2 cm of visible and palpable normal mucosa 1
• Obtain frozen section margin assessment intraoperatively to ensure complete tumor removal and avoid the need for re-resection 1
• Preserve the orbital floor and contents when the tumor does not directly invade these structures, as this maintains visual function and reduces morbidity 6, 7

Critical caveat: If tumor invasion requires resection of the orbital floor, strongly consider orbital exenteration rather than floor resection with orbital preservation, as the latter results in only 17% retention of significant ipsilateral eye function and 44% local recurrence rates 6

Reconstruction Strategy

Defect Classification and Approach

• For defects <2.5 cm, local measures may suffice with close monitoring for spontaneous healing 3
• For defects ≥2.5 cm (the majority of maxillectomy cases), immediate vascularized tissue coverage is mandatory 3, 2

Primary Reconstruction Options

Option 1: Osteomyocutaneous Free Flap (Preferred)

• Use fibula or scapula osteocutaneous free flaps for full thickness defects requiring both structural support and soft tissue coverage, with 92% success rates and only 4% total flap loss 4, 7
• This approach allows future dental implantation and provides superior long-term functional outcomes 2, 7
• Reconstruct the orbital floor with the vascularized bone component to provide stable support for orbital contents 7

Option 2: Myocutaneous Free Flap

• Rectus abdominis myocutaneous free flap is effective for soft tissue reconstruction and palatal resurfacing when bone reconstruction is not required 7
• Achieves good functional outcomes with 85.7% usage rate in one series, though ectropion occurs in 76.9% of cases 7

Option 3: Titanium Mesh with Fascia Lata (When Free Flaps Unavailable)

• Contour 0.2mm titanium mesh to reconstruct the orbital floor and restore midface projection 8
• Cover the titanium mesh with autogenous fascia lata along the orbital floor to prevent orbital fat entrapment and reduce diplopia risk 8
• Use patient-specific orbital reconstruction implants (PSORI) with modified low-profile design when available, as this reduces hardware extrusion rates 5

Major limitation: Titanium mesh extrusion occurs in 25-33% of patients receiving postoperative radiotherapy, making this a suboptimal choice when radiation is planned 8, 5

Option 4: Pedicled Flaps (Last Resort)

• Temporalis muscle transposition or pectoralis major flap may be used in elderly or medically compromised patients who cannot tolerate microvascular surgery 4, 7
• These have 3.6% total flap loss rates but provide inferior facial symmetry compared to free flaps 4

Modified Surgical Approach for Radiation Patients

• Use bioactive resorbable plate systems instead of titanium for zygoma and zygomatic arch fixation in patients requiring postoperative radiotherapy 9
• Employ midface degloving approach rather than external incisions to minimize hardware extrusion risk 5
• Consider modified low-profile implant designs that reduce soft tissue tension and extrusion rates 5

Postoperative Management

Immediate Care

• Prescribe NSAIDs (ibuprofen 600mg TID) or acetaminophen 500mg TID for pain control 1
• Consider corticosteroids in decreasing doses to reduce edema and trismus 1
• Continue broad-spectrum antibiotics for 7-10 days postoperatively 1, 4

Complication Monitoring

• Watch for abnormal bleeding (occurs in 14.5% of cases), typically from posterior superior alveolar artery injury 1
• Monitor for subacute sinusitis manifesting 3-7 days postoperatively with severe suborbital pain, which requires surgical drainage, debridement, and potentially graft removal 1
• Assess for hardware extrusion at every follow-up visit, particularly in radiated patients 8, 5

Radiation Therapy Considerations

• For patients with prior radiation ≥50 Gy, hyperbaric oxygen therapy in conjunction with surgical intervention may be beneficial, particularly for mild ORN cases 3
• Routine prophylactic hyperbaric oxygen is not recommended for standard maxillectomy procedures 3
• Maintain pentoxifylline/tocopherol therapy throughout the healing period in previously radiated patients 3

Critical Pitfalls to Avoid

• Do not attempt orbital floor resection with orbital preservation if postoperative radiation fields will include the eye, as this results in poor visual outcomes and high recurrence rates 6
• Do not use titanium mesh reconstruction as first-line in patients who will receive postoperative radiotherapy due to 25-33% extrusion rates 8, 5
• Do not underestimate defect size—defects ≥2.5 cm require vascularized tissue coverage, not local measures alone 3, 2
• Do not delay radiation therapy for dental healing if this compromises oncologic control; oncologic outcomes take absolute priority 3
• Do not perform dental extractions in high-dose radiation zones (≥50 Gy) without pentoxifylline/tocopherol prophylaxis and antibiotic coverage 3