MD Codes™: A Methodological Approach to Facial Aesthetic Treatment with Injectable Hyaluronic Acid Fillers

To handle the enormous variability among faces, the MD Codes algorithms were developed to guide selection of the appropriate MD Codes for each individual. Not every patient will need all of the codes within each equation. For example, the algorithm for saggy cheeks (Fig. 2a) guides the selection of MD Codes based on the presence or absence of volume loss. When comparing a daughter, a mother, and a grandmother, the daughter may have fullness in her cheek area and present with only a mild degree of sagginess. Thus, according to the saggy cheeks algorithm, she would benefit from treatment of only Ck1. The mother may present with sagginess and volume loss concentrated only in the medial aspect. She may benefit from treatment of Ck1, Ck3, and Ck4. The grandmother, due to a greater severity of volume loss and sagginess, may be eligible for treatment of all five cheek anatomical areas (Ck1 + Ck2 + Ck3 + Ck4 + Ck5).

Someone with a tired look may also present with sunken temples. The algorithm for sunken temples (Fig. 2b) guides clinicians on the selection of MD Codes based on the severity of volume loss in the temples. In the case of the daughter, the mother, and the grandmother, the daughter may not need any temple treatment as she may have no deficiency there. The mother may present with mild to moderate volume deficit in the temples and may benefit only from treatment of T1. The grandmother, with a more severe temple deficiency, may benefit from treatment of T1 and T2.

The algorithms for treatment of the tear troughs and the eye bags are shown in Fig. 2c and d, respectively. The vast majority of people presenting with distracting tear troughs and eye bags also have saggy cheeks and/or volume loss that would first require treatment of the cheeks (foundation) and the temples (contouring). Only a young patient who presents with no volume loss or sagginess may benefit from direct treatment of the tear troughs (Tt1 + Tt2 + Tt3), but this rarely occurs in clinical practice.

Combining the MD Codes identified using the three algorithms to treat a tired look may result in, for example, a total of seven MD Codes for the mother ([Ck1 + Ck3 + Ck4] + [T1] + [Tt1 + Tt2 + Tt3]), and 10 codes for the grandmother ([Ck1 + Ck2 + Ck3 + Ck4 + Ck5] + [T1 + T2] + [Tt1 + Tt2 + Tt3]). Thus, the difference between the treatment plans for the mother and the grandmother is in the number of codes, based on degree of severity; the grandmother does not necessarily receive more volume per code, which could lead to unnatural results and adverse events. Once the MD Codes are selected for the individual patient, a tired look is addressed step by step, first providing foundation in the midface, then contouring at the temples, and, finally, directly addressing the tear troughs or eye bags as refinement. Additional MD Codes algorithms are provided in Figure S1 in the Supplemental Materials. Clinicians must explain to patients who focus only on the refinement step that the foundation and contour should be addressed first, as represented in these algorithms.

Over the foundation, contour, and refinement steps, the MD Codes approach can result in the progressive removal of the unfavorable attributes of tiredness, sadness, and sagginess, and may enhance the positive attributes of looking younger and more feminine. Figure 3 illustrates the change in appearance that may be observed as additional MD Codes are used to add volume in successive treatment steps. Notice the improvement in the patient’s cheek immediately after providing midface foundation (Ck1 + Ck2 + Ck3 + Ck4) and contouring of the upper face (T1) with a total 4 mL of HA filler. The patient’s jawline was improved after contouring of the lower face with an additional 4 mL of HA filler (C1 + C2 + Jw4 + Jw5). Improvement in her double chin was also achieved by addressing the cheek first, then contouring the chin and anterior jawline. Foundation and contour were reinforced with additional codes (Ck3 + C6), refinement of the periorbital area improved the tear troughs (Tt1 + Tt2 + Tt3), and perioral refinement addressed the lips and nasolabial folds (Lp₁ + Lp2 + Lp³ + Lp₃ + Lp5 + Lp6 + NL1) using a final 9 mL of filler. The image on the right in Fig. 3 shows the patient immediately after the total injection volume of 17 mL. Increasing the number of MD Codes over these multiple treatment steps yielded more impactful results. This patient received all treatment steps in a single session; however, the author suggests planning treatment such that 4 mL is injected per session. To achieve the best possible results, more volume may be provided by using additional codes in successive sessions to reinforce facial restructuring in the midface, cheek, and jawline.

One of the biggest challenges clinicians may encounter during treatment planning is estimating the total volume of product required for treatment. Often a clinician may discover mid-treatment that the planned number of syringes is not adequate. When fillers were first introduced to the market, it was common for clinicians to treat only nasolabial folds or to distribute the product of one syringe (1 mL) among many sites, leading to a lack of visible results and patient dissatisfaction. Clinical judgment should be used to determine the appropriate total volume based on individual patient needs; however, a recommended injection volume, or active number, is provided with each MD Code to simplify the estimation of the total volume. The active numbers are minimum volumes needed to achieve visible and reproducible results (Table 3); actual injection volumes should be determined by the clinician for each patient.

The analogy of building a house is again useful for understanding the importance of volume planning. The amount of material to be used in each stage of construction is critical and must be carefully calculated in advance, in order to create a financial plan and ensure that the structure will be sound. Similarly, clinicians must know beforehand how many syringes they will need for each treatment step, to be able to communicate accurate cost information to the patient and to achieve optimal and long-lasting results.

Volume recommendations provided here (and to be presented in greater detail in a future publication) were established progressively by the author based on clinical experience with more than 10,000 syringes over a 4-year period. Clinicians may follow a simple rule: bolus injections should not exceed a total volume of 0.3 mL into the same compartment, to avoid disturbing muscle movement. There are three exceptions to this rule: when injecting the temple (T1 + T2) and the mandible angle (Jw1), the active numbers are 0.5 mL. When fanning in a specific area with a cannula, no less than 0.5 mL should be used.

To estimate the product volume needed during treatment planning, clinicians should first determine the MD Codes required for their patient, using the algorithms as described above. The active numbers for each code are then summed to estimate the minimum total volume required. For example, treating a tired look may require the following MD Codes:

Note that when both Ck1 and T1 are injected during the same session, the active number for T1 is increased from 0.5 to 0.7 mL to allow for use of an entire 1-mL syringe. For this specific treatment, the clinician will need a total of four syringes, two for each side of the face. All patients whose treatment plans include the same MD Codes will start at the same estimated minimum total volume. In this way, the MD Codes approach reduces variability in outcomes by focusing on facial attributes rather than on the differences in age, gender, and ethnicity in the faces that harbor them.

A 43-year-old Caucasian woman (Fig. 4) presented with signs of sagginess in the midface and lower face, looking tired around the eyes and looking sad around the eyes and mouth. The first step of treatment provided foundation in the midface by addressing the cheek codes. The algorithm for saggy cheeks was used to select the MD Codes for injection and, as mentioned previously, always starts with the lateral lifting cheek vectors (Ck1 + Ck4) and proceeds to the anterior (Ck2) and medial (Ck3) cheek. Contour was then provided to the upper face by addressing the volume deficit in the temple (T1), which indirectly improved the appearance of her eye bags. Next, the lower face was contoured by injecting C1 to improve the labiomental angle, C2 to increase the vertical height of the chin, and Jw4 and Jw5 to advance the mandible and to improve the prejowl area. Midface foundation was reinforced by injecting Ck3 with two different approaches, first the deep malar fat pad, then the suborbicularis oculi fat (SOOF). The lateral aspects of the chin and prejowl areas were also addressed by injecting C6. Finally, periorbital refinement was provided in the tear trough area (Tt1 + Tt2 + Tt3). Refinement in the perioral area was provided by addressing the nasolabial folds (NL1 + NL2) and lip volume (Lp¹ + Lp₁ + Lp⁶). Lastly, Jw1 was injected to reshape the mandible angle.

Images taken immediately after treatment illustrate improvements in the patient’s midface, jawline, periorbital, and perioral areas (Fig. 4a–c). The reshape of the jawline apparent in the oblique view (Fig. 4b) was accomplished by contouring with injections in C1, C2, Jw4, Jw5, C6, and Jw1. In the oblique view, improvement of the eye bags was observed after injection of Ck1, T1, Ck2, Ck3 and Tt1, Tt2, Tt3. The periorbital lines improved after addressing periorbital deflation. In the photographs taken immediately after treatment, you can see that using the MD Codes algorithm to select codes and focusing treatment on foundation, contour, and refinement resulted in the elimination of the unfavorable tired, saggy, and sad attributes of the face and enhancement of the positive attributes of looking younger, more feminine, and attractive. This patient (and the following 2 cases) received all injections in a single session, for educational purposes. However, in clinical practice, this treatment could be provided in multiple sessions, with four syringes of HA filler injected during each session.

A 44-year-old woman (Fig. 5) presented with facial signs of sagginess, tiredness, and sadness, represented by the presence of saggy cheeks, eye bags, and marionette lines. Before treatment, indentation was apparent on the anterior right cheek when she smiled (Fig. 5c). The first treatment step focused on providing foundation in the midface (Ck1 + Ck4) and contouring the upper face (T1). The second step addressed the lower face by treating the chin (C1 + C2) and anterior jawline (Jw4 + Jw5). In step 3, due to the degree of severity and to further improve the jawline, Jw4  and Jw5 were reinjected. In the same step, Ck3 was injected to compensate for the deep malar fat pad and then the SOOF. The final step included periorbital and perioral refinement through injections in the tear trough area (Tt1 + Tt2 + Tt3), the nasolabial folds (NL1 + NL2), and lip (Lp¹ + Lp₁ + Lp6). Images taken immediately after the last treatment step illustrate the changes in facial shape, including increased volume in the cheeks, and the more triangular appearance of the chin (Fig. 5a). After the lip treatment, an upturn of the oral commissures was observed. In the oblique view, the improvement of saggy cheeks, eye bags, and the jawline resulted in a less tired, less saggy, and less sad appearance than before treatment (Fig. 5b). Injection of CK1 and Ck4 improved cheek sagginess and reduced the indentation of the woman’s right cheek, making her smile appear more attractive and natural (Fig. 5c).

A 42-year-old Caucasian man (Fig. 6) presented with a narrow face, saggy cheeks, a poorly defined jawline, and a double chin. The first treatment step focused on the same lateral lifting vectors as in case 2 (Ck1 + T1 + Ck4) to build midface foundation and to contour the upper face. Step 2 focused on improving chin projection by treating the chin (C1 + C2) and jawline (Jw4 + Jw5) in the same manner that treatment was delivered for cases 1 and 2. For this patient, repeat treatment was required in a subsequent session due to the degree of severity. The lateral chin area and prejowl sulcus (C6), the lateral lower chin (C5), and the chin apex (C2) were then addressed. In addition, Ck1 was injected for the top-model look (TML; Ck1), which refers to the injection of Ck1 with a cannula to create a linear appearance of the zygomatic arch. Ck3 was injected to address the deep malar fat pad. Injection of Ck1 (TML) was repeated in a later session to further reinforce the zygomatic width, and Jw3 was injected to sharpen the jawline. Immediately after treatment, changes in facial shape could be observed, with improvements in the bitemporal, bizygomatic, and bigonial widths due to the injections of T1, Ck1, and Jw1, respectively (Fig. 6a). Indirect improvements to the tear trough area could also be observed following the injection of Ck1, T1, and Ck3. The chin presented with a more square shape, and there was less indentation of the labiomental sulcus and the prejowl area. Note that C1, C2, C5, and C6 were injected, as well as Jw4 and Jw5, to improve chin shape and address the double chin. When the patient smiles, a reduction in his double chin and smile lines can be seen (Fig. 6b). His smile looks more confident due to improvements in the lateral structure of the face (Ck1 + T1 + Ck4) and support of the deep malar fat pads (Ck3). Injection of C1 also lifted the lower lip and lessened showing of his lower teeth when smiling. The oblique view (Fig. 6c) shows improved definition of the zygomatic arch resulting from Ck1 (TML), a better jaw angle due to treatment of Jw1, a more square chin shape due to treatment of C1, C2, C5, and C6, and a more defined jawline due to treatment of Jw3. When the patient looked down, the improvement of facial shape and increased stability in the lower lip helped to create a more confident appearance (Fig. 6d).