![]() ![]() Problems with the lower eyelid can be minimized by optimizing the fit, size, and thickness of the implant. Regardless of which fixation is placed over or posterior to the orbital rim, the overlying soft tissues must not be compromised in terms of form and function. It is debated whether or not to extend the anterior part of the mesh over the infraorbital rim. The defect size can be measured by the reading on the orbital retractor or any other instrument. It is crucial that in case of combined fracture types (eg, displaced zygoma fracture) the final defect size is only measured after proper repositioning of the outer frame. This can provide valuable information for future recommendation.Ī careful assessment of the defect size should be performed preoperatively with the CT scan in the sagittal view which is in the course of the orbital nerve, plus the coronal view showing the transverse extent. Modern imaging analysis offers a unique chance to quantitatively asses the surgical result and stability over the time. There is a paucity of evidence to support the ideal choice for an orbital implant. There are different preferences of implant material depending on regional differences, variations in schools of teaching, and socio-economic factors. This is why critical consideration of the use of resorbable materials is necessary. Secondary changes to this contour are undesirable. Reconstruction of the dislocated orbital walls is demanding. Many surgeons recommend using materials that allow bending to an anatomical shape, that are radiopaque (to allow for intra- or postoperative radiologic confirmation of placement), and stable over time. Non-prebent versus preformed (anatomical) plates.Autogenous/allogenous/xenogenous versus alloplastic material.There is hardly any anatomic region in the human body that is so controversial in terms of appropriate material used for fracture repair: In large defects, preformed anatomic implants can help restore the complex internal orbital anatomy. This can be accomplished using various materials. Therefore, one is reconstructing missing bone rather than reducing bone fragments. The reason for this is that the bony walls are comminuted and/or bone fragments are missing. The majority of cases require reconstruction of the orbital floor to support the globe position and restore the shape of the orbit. ![]() The unique and complex anatomy of the orbit, unless prebent plates are used, requires significant contouring of the implants to restore the proper anatomy. Note: In children, entrapment of the eye muscles is more common than in adults this might be due to the higher elasticity of the bony structures (green-stick fractures are more common). Entrapment is often associated with severe ocular pain on attempted range of motion, as well as nausea and vomiting, especially in children. Clinical examination should give evidence on impaired ocular muscle function. Entrapment requires urgent freeing of the muscle to prevent necrosis of the incarcerated muscle. The inferior rectus muscle is the most common ocular muscle to become entrapped with an orbital floor fracture (trap-door phenomenon) and this may not be visible on conventional x-rays. In some younger patients, the so-called trap-door phenomenon can occur in which there is danger of necrosis of the entrapped rectus muscle within a few hours immediate release of entrapped tissues is necessary.Įntrapment of eye muscle (especially in children) Usually there is no need for emergency treatment in orbital floor/medial wall fractures unless there is severe ongoing hemorrhage in the orbital cavity, the paranasal, or nasal cavity. This is one reason why the surgeon has to assess appropriate vision as soon as possible after injury and/or surgery. Note: retrobulbar hematoma is one of the most severe postoperative complications in patients who have undergone orbital trauma and/or surgery. A fistula of this nature requires appropriate preoperative imaging. Alternative methods such as transconjunctival pressure release and/or lateral canthotomy and inferior cantholysis should be considered according to patient condition.Īn exception may be where there is a pulsating exophthalmos which may be a sign of carotid-cavernous sinus fistula. Transcutaneous transseptal incisions may help evacuate the hematoma and release the periorbital pressure. ![]() This could mean urgent treatment under local anesthesia even in the emergency room prior to further imaging. If a retrobulbar hematoma in the cooperative patient results in blindness, the time window to release the intraorbital pressure is limited to around one hour measured from the onset of blindness. If a retrobulbar hematoma leads to a tense, proptotic globe, emergency decompression should be considered. ![]()
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