An anatomical study of the pathophysiology of carotid cavernous sinus fistula associated with Le Fort III osteotomy

Reducing the risk of unfavourable fractures in Le Fort III osteotomy via a navigation-guided technique

The aim of this study was to investigate the clinical feasibility of reducing the risk of unfavourable fractures during Le Fort III osteotomy by using a navigation-guided technique. A study was carried out involving 20 patients with Crouzon syndrome treated with Le Fort III osteotomy and distraction osteogenesis from 2018 to 2023 at the International Hospital of Peking University. The Le Fort III osteotomy procedure in experimental group (9 patients) was carried out under the guidance of navigation technique, while in historical control group (11 patients) was carried out by free hand. Immediate postoperative CT scans were acquired within 24h after surgery to observe the osteotomy lines and detect unfavourable fracture lines. There were 4 patients with unfavourable fractures in the navigation group (4/9 = 44%) while 10 patients in the freehand group (10/11 = 91%), with a statistically significant difference in the probability of unfavourable fracture and the number of fracture lines between the two groups (P < 0.05). The difference in unfavourable fracture incidence in the two groups was significant in zygomatic area (P < 0.05) while not significant in mid-palatal area (P > 0.05). And the surgical duration of the navigation group was significantly shorter than that of the freehand group (216 min vs 280 min) (P < 0.05). The above findings suggest that the navigation-guided technique is effective in reducing the risk of unfavourable fractures in Le Fort III osteotomy procedure and decreasing the surgical duration.

Separation patterns of orbital wall and risk of optic canal injury in Le Fort 3 osteotomy

PURPOSE

The authors hypothesized that the risks of optic canal injury in down-fracturing after Le Fort 3 osteotomy vary depending on the separation patterns of the orbital walls. This study verifies this hypothesis using biomechanical simulation.

METHODS

Ten finite-element skull models were produced using computer tomography data from ten persons. These models were modified to simulate Le Fort 3 osteotomy models by removing junctions between the neurocranium and facial cranium. The separation of the orbital wall was performed in four differing ways. In Type 1, all walls were completely separated. In Type 2, only the lateral wall was separated. In Type 3, the inferior wall was left unseparated. In Type 4, the lateral wall was left unseparated. Biomechanical simulation of down-fracturing was performed on the resulting 40 models. By observing irregular fractures occurring inside the orbit, the rate of optic canal involvement was evaluated for each of the four orbital-wall separation patterns.

RESULTS

The rates of optic canal involvement were: Type 1 (0/10), Type 2 (0/10), Type 3 (0/10), and Type 4 (4/10).

CONCLUSION

When the lateral wall is incompletely separated in Le Fort 3 osteotomy, irregular fracture can develop inside the orbit and involve the optic canal during the down-fracturing process. Hence, the lateral orbital wall should be completely separated to avoid potential blindness due to optic canal injury.

A rare case report of complications in craniofacial injuries: Cavernous sinus-carotid fistula

RATIONALE

Cavernous sinus-carotid fistula (CCF) is a rare complication of craniofacial injuries in patients receiving oral and maxillofacial surgical care.

PATIENT CONCERNS

A retrospective review of 15 patients with CCF records was conducted. In addition, we present a rare case of a 32-year-old Chinese woman with CCF receiving oral and maxillofacial surgical care.

DIAGNOSES

Digital subtraction angiography (DSA) confirmed a diagnosis of CCF.

INTERVENTIONS

Endovascular surgery was performed via the femoral artery under general anesthesia without any complications.

OUTCOMES

The postoperative course was uneventful, and the subjective and objective ophthalmic symptoms had resolved.

LESSONS

The symptoms of CCF may be delayed for several days or weeks. Thus, maxillofacial surgeons should be aware of this and avoid the untimely repair of facial fractures with potentially disastrous consequences. Interventional neuroradiologic approaches that involve the use of a detachable balloon have made it possible to care for patients with CCF without any complications.