Fig. 15.1
An example of unfavorable results after standard reduction malarplasty. A 27-year-old male showing under-corrected prominent cheekbone, which was treated by conventional L-shaped osteotomy technique. (Left) Preoperative view, (Right) 3 months after reoperation
Therefore, in order to meet the patients’ demands, different strategies are needed according to the subtype of the zygomatic prominence as all patients have different degrees of protrusion and morphology of the zygomatic bone. In this article, detailed description of the subtype of the zygomatic prominence and its corresponding surgical techniques are presented.
Patient Consultation and Assessment
Preoperative assessment should include a history of previous malar contouring procedures, including autologous fat injection, filler injection, or alloplastic implant placement such as silicone or Medpor®. Especially, patients with prior history of fat or filler injection are more likely to have greater chance of cheek drooping. In addition, special care should be taken not to neglect the inflammatory conditions such as sinusitis or periodontal disease. This is because such conditions can be exacerbated by surgery and are therefore best treated prior to surgery. The degree of eye prominence should also be examined prior to surgery, as this can influence the optimal reduction of protruding inferolateral orbital rim. In particular, patients with enopthalmic eyeballs are at risk for undercorrection and should be considered for sufficient reduction of external orbital rim.
Preoperative Analysis
The evaluation of the malar area is somewhat hindered by a lack of anthropometric or cephalometric landmarks along its complex three-dimensional curvature [10]. The point zygion (Fig. 15.4, point Zy), which defines the maximum interzygomatic distance (zygion-zygion), does not correspond to the area of maximum malar prominence (area mmp). Malar contouring involves not only the zygomatic region but also the periorbital region. Pitfalls can be avoided if one is conscious about these relationships. Evaluation should include the three basic views: frontal, three-quarter oblique, and basal. Direct physical examination is the key process to evaluate the patient’s problems and establish a surgical plan. Clinical photos are necessary as is radiologic examination including frontal view, lateral view, submentovertex view, and Waters’ view. CT scan with 3D view is also essential to evaluate the shape of the zygomatic complex.
Frontal Evaluation
The frontal evaluation can be simplified by visualizing an anterior and posterior facial plane. The anterior facial plane is defined by the superior temporal line, lateral border of the lateral orbital rim, malar prominence, midface, and mentum (Fig. 15.2, blue line). The posterior facial plane is circumscribed by the contour line of the head (Fig. 15.2, red line). A combination of variable forms of these two planes defines a variety of facial shapes. In the case where the cheekbones protrude outwardly, the facial line connecting the temple-zygoma-cheek-mandible angle constitutes a very convoluted line (Fig. 15.2). Volume and position of zygomatic body and bizygomatic width are key variables to be considered. The volume of zygomatic body determines the amount of ostectomy during the surgery. If the volume of zygomatic body is large, wider resection of zygomatic body is planned. However, overzealous reduction results in flat or deficient look. Therefore, keeping the adequate volume of zygomatic body in anteroposterior dimension and transverse plane is essential. The position of zygomatic body is measured in both, its most lateral margin and in its maximal projection. Outer margin of zygomatic body is observed in conjunction with temple and cheek. To narrow the anterior midfacial width, lateral margin of cheekbone should be trimmed or moved inward. If the outer margin of cheekbone is placed wide, the amount of narrowing and medialization should be maximized, and ostectomy should be combined.
Fig. 15.2
Anterior and posterior facial contour lines. The anterior facial contour line connects the temple, zygomatic body, cheek, and mandible body (blue line), while the posterior facial contour line connects the temple, zygomatic arch, mandible angle, and chin (red line). If the anterior contour line is too convoluted, the patient gives a “strong,” “offensive,” “old,” “tired,” “masculine” impression. The posterior contour line reflects the facial width and facial size
The point of maximal malar projection (MMP) is the point where the outer contour of the zygomatic complex protrudes mostly in basal three-quarter view. If the reduction of zygomatic body is performed by shaving, or osteotomy is placed lateral to MMP, this point stays unchanged while outer margin of zygomatic body being narrowed, resulting in unnatural, boxy shape cheekbone. As stated before, the purpose of reduction malarplasty is not resection of projection; therefore adequate projection and position of maximal malar projection is the key in postoperative result. The point of maximal malar projection is marked, and the surgeon decides where to move this point three-dimensionally. The amount of medial repositioning and ostectomy is closely related to the reduction of anterior facial width. Ideal position of MMP may vary in different ethnicities; however, the following lists two simple methods of determining the ideal position of MMP (Fig. 15.3).
Fig. 15.3
Determining the ideal position of the maximal malar projection (MMP). (a) Hinderer analysis. (b) Wilkinson analysis
Hinderer Analysis
The MMP is determined at the point of intersection of two lines, where the first line connects the lateral canthus and oral commissure and the second line connects the nasal alar base and the tragus line. The new location is a point placed in juxtaposition to the crossed lines in the upper-outer quadrant [11].
Wilkinson Analysis
A line is dropped vertically downward from the lateral canthus to the inferior border of the mandible. The MMP is located at one-third the distance from the lateral canthus to the angle of mandible [12].
Three-Quarter Oblique Evaluation
Malar eminence is clearest in the oblique view at approximately 34° from the sagittal plane. Therefore, several morphologic subcomponents of 45° cheekbone can be identified, which include convexity (degree and location of protrusion) of the zygomatic body and arch, innominate semi-horizontal groove between orbital rim and malar prominence (hereafter referred to as “orbito-malar groove”), and protrusion of inferolateral orbital rim, location of MMP (maximal malar point).
Basal Evaluation
In general, Asian faces have a brachyfacial characteristic with a flat suborbital area. When viewed from below, the lack of projection in the suborbital area and protruding zygomatic arch may form a 90° angle that looks boxy in appearance (Fig. 15.4). In this case, the face appears flat and one-dimensional, which makes the face appear even wider. Therefore, change in the shape and position of the zygomatic body is needed to create a midface fullness that appears more three-dimensional and youthful. This view helps in evaluating symmetry and also facilitates evaluation of the zygomatic arch.
