Intraoperative Use of Ultrasonography in the Reduction of Zygomatico-Maxillary Complex Fractures

Study Design: A single blind randomized controlled study. Objective: The aim of this study is to evaluate the use of ultrasonography intraoperatively to assess the reduction of unilateral zygomatic complex fractures with a control group using the conventional blind digit palpation. Methods: The study comprised of a sample size of 24 patients with 21 male and 3 female patients. Patients of all age groups diagnosed with unilateral displaced zygomatic complex fracture with or without mandible fracture were included in the study. The subjects were randomized into study and control groups based on a standard protocol with a total of 24 patients. Imaging was in the form of a preoperative and postoperative 3D computed tomography scan with reconstruction of the maxilla and mandible to interpret the diagnosis for all subjects. The inter-fracture distance of the fractured infraorbital rim were measured in 3 dimensions (antero-posterior, medio-lateral and supero-inferior) and compared pre and postoperatively. Preoperative, intraoperative and postoperative ultrasonographic examination was performed and recorded on all patients at the frontozygomatic region, infraorbital rim and zygomatic buttress to assess the proximity of the fractured margins pre reduction, post reduction and post fixation of the fracture segments. Result: Statistical analytic results were significant in all 3 dimensions when measured postoperatively using computed tomography. Conclusion: Ultrasonography is an effective screening and intraoperative tool in the armamentarium of oral and maxillofacial surgery to assess zygomatic complex fractures, avoiding incisions in aesthetic areas of the maxillofacial region.

Virtual splint registration for electromagnetic and optical navigation in orbital and craniofacial surgery

In intra-operative navigation, a registration procedure is performed to register the patient’s position to the pre-operative imaging data. The registration process is the main factor that determines accuracy of the navigation feedback. In this study, a novel registration protocol for craniofacial surgery is presented, that utilizes a virtual splint with marker points. The accuracy of the proposed method was evaluated by two observers in five human cadaver heads, for optical and electromagnetic navigation, and compared to maxillary bone-anchored fiducial registration (optical and electromagnetic) and surface-based registration (electromagnetic). The results showed minimal differences in accuracy compared to bone-anchored fiducials at the level of the infra-orbital rim. Both point-based techniques had lower error estimates at the infraorbital rim than surface-based registration, but surface-based registration had the lowest loss of accuracy over target distance. An advantage over existing point-based registration methods (bone-anchored fiducials, existing splint techniques) is that radiological imaging does not need to be repeated, since the need for physical fiducials to be present in the image volume is eradicated. Other advantages include reduction of invasiveness compared to bone-achnored fiducials and a possible reduction of human error in the registration process.

Inferomedially impacted zygomatic fracture reduction by reverse vector using an intraoral approach with Kirschner wire

Background In inferomedially rotated zygomatic fractures sticking in the maxillary sinus, it is often difficult to achieve complete reduction only by conventional intraoral reduction. We present a new intraoral reduction technique using a Kirschner wire and its clinical outcome.Methods Among 39 inferomedially impacted zygomatic fractures incompletely reduced by a simple intraoral reduction trial with a bone elevator, a Kirschner wire (1.5 mm) was vertically inserted from the zygomatic body to the lateral orbital rim in 17 inferior-dominant rotation fractures and horizontally inserted to the zygomatic arch in nine medial-dominant and 13 bidirectional rotation fractures. A Kirschner wire was held with a wire holder and lifted in the superolateral or anterolateral direction for reduction. Following reduction of the zygomaticomaxillary fracture, internal fixation was performed.Results Fractures were completely reduced using only an intraoral approach with Kirschner wire reduction in 33 cases and through an additional lower lid or transconjunctival incision in six cases. There were no surgical complications except in one patient with undercorrection. Postoperative 6-month computed tomography scans showed complete bone union and excellent bone alignment. Four patients experienced difficulty with upper lip elevation; however, these problems spontaneously resolved after manual tissue lump massage and intralesional steroid (Triamcinolone) injection.Conclusions We completely reduced infraorbital rim fractures, zygomaticomaxillary buttresses, and zygomaticofrontal suture fractures in 84% of patients through an intraoral approach alone. Intraoral Kirschner wire reduction may be a useful option by which to obtain effective and powerful reduction motion of an inferomedially rotated zygomatic body.

Transconjunctival Approach Using Lateral Skin Extension for Reconstruction of Orbit Zygomatic Complex Fractures: Technique Description and a Case Series Analysis

Study Design: A descriptive-observational study of a series case report of patients diagnosed with orbito-zygomatic complex (OZMC) fracture with lateral wall involvement, was conducted. All patients were assessed in the Oral and Maxillofacial Surgery Service at Hospital El Carmen, Maipu, Santiago, Chile. Objective: The purpose of this study was to evaluate a single-institution experience with the transconjunctival approach to the orbit, utilizing a lateral skin extension as unique approach to access to fronto-zygomatic suture, infraorbital rim and/or orbital floor. Method: The authors identified 41 patients with OZMC fractures who underwent to surgical treatment over a 45 months period. Among this group, 21 patients needed fixation with osteosynthesis of the frontozygomatic suture, and 16 of whom were treated with the approach being studied. The authors assessed scleral exposure, eyelid position changes, ectropion, and entropion as outcome measures, and reported satisfactory outcomes at a minimum of 9 months follow-up. Conclusions: This study concludes that in our experience, the transconjunctival approach utilizing a lateral skin extension allows a direct, easy, and quick access to the entire infra orbital rim, orbital floor, fronto-zygomatic suture and lateral wall of the orbit, up to spheno-zygomatic suture, with low associated morbidity and complications.

Clinical Criteria for Selective Exploration of Orbital Floor in Zygomaticomaxillary Complex Fractures

Purpose: Exposing the orbital floor requires a surgical procedure that has its own challenges. Despite the meticulous clinical examination followed by sophisticated imaging modalities, orbital floor defects associated with zygomaticomaxillary complex (ZMC) fractures may evade diagnosis and appropriate management. If surgeons can decide about the need for orbital floor exploration in patients with ZMC fracture, the chance of a postoperative eyelid deformity can be prevented. The aim of this article is to assess whether an association exists between the pattern of fracture line and the need for exploration of the orbital floor in ZMC fracture. Materials and Methods: A retrospective study of 94 patients with isolated, unilateral ZMC fractures who were treated at our unit by open reduction of the ZMC complex with internal orbital exploration from January 2016 to January 2018. The records of all patients were reviewed and specific data related to fracture pattern and orbital floor defect were registered and assessed. Results: Of the 94 cases with isolated, unilateral ZMC fractures, in 80 cases the fracture line propagated to the orbital floor, which required exploration but did not required any reconstruction and only the infraorbital rim was addressed; 14 of them required orbital floor reconstruction. Among the cases which required orbital floor reconstruction, the majority of the cases where those with fracture involving medial side of infraorbital foramen (n = 10) followed by lateral side (n = 3) and through the foramen (n = 0) and lastly bilateral side of the foramen (n = 1). Conclusion: The present study highlights the pattern of fracture line at the level of infraorbital rim can predict the need for orbital floor exploration while treating ZMC fractures for purpose of orbital floor reconstruction. Based on the results and a review of the records, authors strongly recommend the need for exploration of orbital floor when the fracture line passes medial to the infraorbital foramen.

A Study of the Head during Prenatal and Perinatal Development of Two Fetuses and One Newborn Striped Dolphin (Stenella coeruleoalba, Meyen 1833) Using Dissections, Sectional Anatomy, CT, and MRI: Anatomical and Functional Implications in Cetaceans and Terrestrial Mammals

Our objective was to analyze the main anatomical structures of the dolphin head during its developmental stages. Most dolphin studies use only one fetal specimen due to the difficulty in obtaining these materials. Magnetic resonance imaging (MRI) and computed tomography (CT) of two fetuses (younger and older) and a perinatal specimen cadaver of striped dolphins were scanned. Only the older fetus was frozen and then was transversely cross-sectioned. In addition, gross dissections of the head were made on a perinatal and an adult specimen. In the oral cavity, only the mandible and maxilla teeth have started to erupt, while the most rostral teeth have not yet erupted. No salivary glands and masseter muscle were observed. The melon was well identified in CT/MRI images at early stages of development. CT and MRI images allowed observation of the maxillary sinus. The orbit and eyeball were analyzed and the absence of infraorbital rim together with the temporal process of the zygomatic bone holding periorbit were described. An enlarged auditory tube was identified using anatomical sections, CT, and MRI. We also compare the dolphin head anatomy with some mammals, trying to underline the anatomical and physiological changes and explain them from an ontogenic point of view.