The forehead and temporal regions play a significant role in overall facial attractiveness due to their contribution to facial contour and symmetry. The forehead aesthetic subunit can be described as starting from the glabella inferiorly to the hairline superiorly and ending laterally at the temporal crest. The temporal subunit begins from the temporal crest superiorly, encompassing the scalp hairline posteriorly and the lateral canthus anteriorly as well as the zygoma inferiorly. Enhancing the shape and symmetry of these regions can lead to a more youthful and balanced look, influencing the perceptions of facial attractiveness. Ellanse (Sinclair Pharmaceuticals) is composed of biodegradable polycaprolactone microspheres suspended in a carboxymethylcellulose gel carrier. Polycaprolactone is gradually absorbed over time, stimulating collagenesis in the treated areas. Our study is based on existing epistemology, wherein Ellanse was studied extensively in the context of rejuvenating the forehead [1], nasolabial folds [2], and hands [3], with patient satisfaction rates of up to 80%. Additionally, the longevity of aesthetic results is well maintained at 24 months with a 2.33-point improvement on the GAIS (Global Aesthetic Improvement Scale). Kim and Van Abel [4] and Nicolau and Marijnissen-Hofsté [5] used histological analysis to demonstrate a polycaprolactone-based treatment increases the ratio of Type I collagen to Type III collagen at 18 to 24 months. In youthful skin, collagen I and collagen III compose approximately 80% and 15% of total skin collagen, respectively [6], and this ratio decreases with senescence of the skin. Consequently, increasing the ratio of Type I to Type III collagen with polycaprolactone microspheres exerts an anti-ageing effect on the tissue. In summary, Ellanse enhances facial volume and improves the structural integrity of the skin by boosting collagen production. Ellanse M is selected for its demonstrated long-lasting rejuvenation effects at 24 months.

The analysis involved 86 consecutive patients who underwent treatment for forehead rejuvenation between 2016 and 2018. They received forehead and temple augmentations and lateral browlifts using Ellanse M filler (1 ml/syringe) along with botulinum toxin A (Botox, Abbvie) for forehead wrinkles. An average of 5 to 6 vials (1 ml/vial) of Ellanse filler were used in a single session. Patients were then followed-up at 3 days, 1 week, 1 month, 3 months, and 2-year intervals with photographic documentation using both 3D facial imaging by 3D LifeViz^® (Quantificare) and a digital camera (Cannon SLR DS126801). Informed consent was obtained from all patients, and the research was conducted in accordance with the principles outlined in the Declaration of Helsinki, 2018. Additionally, ethical approval for this study was granted by the iCare Ethics Approval (Approval: IMAC/2024/733/003).

Technique

Patients were counselled regarding the classification of their forehead shape and the amount of Ellanse fillers required. Regional block was performed using lidocaine (2%) with epinephrine (1:80,000) over 4 areas to anesthetize nerves that included the bilateral supratrochlear and supraorbital nerves and the lateral branches of the supraorbital nerves. Each syringe of Ellanse (1 ml/syringe) is premixed with 0.2 ml of lidocaine using 20 back and forth strokes to ensure a homogenous blend [7]. Ellanse was then injected into the forehead using a Dermasculpt 25 G 50 mm (Medical Brokers) cannula through the temporal crest and midline approaches. Care was taken to ensure that Ellanse was injected in the supraperiosteal plane using a retrograde manner in the central and middle fat compartments (Fig. 1). In the region of the supratrochlear and supraorbital vessels, Ellanse was injected and then massaged into the vessel region for augmentation.

Figure 1. Forehead rejuvenation demonstrating dissected supraorbital vessel.

Rejuvenation of the glabella required detailed knowledge of the vascular anatomy. The glabella region consists of the following arteries:

• 1)

  The central artery that is a branch of the dorsal nasal branch and possesses a diameter of less than 1 mm [8] passes through the subcutaneous tissue layer and became slightly more superficial in the frontal prominence area.

• 2)

  The paracentral artery that is a branch of the angular artery and possesses a mean diameter of less than 1 mm also passes into the subcutaneous tissue layer and becomes more superficial in the frontal prominence area [9]. Sykes et al. [10] reported that the central artery or paracentral artery was observed in 20% of cases.

To rejuvenate the glabellar region, Ellanse is injected using a linear retrograde technique on the supraperioteal layer perpendicular to the direction of the central and paracentral arteries to avoid inadvertent intra-arterial injection. The location and depth of the supraorbital, supratrochlear, central, and paracentral arteries can be determined using Point of Care Ultrasound (POCUS) to avoid inadvertent injury.

Temporal augmentation was performed by depositing a 0.2 ml bolus of Ellanse with each treatment using the “one-up, one-over” technique proposed by Trindade de Almeida et al. [11] in the temporal region. Browlifts were performed by injecting 0.15 to 0.2 ml in linear threads to support the orbital retaining ligament and elevate the lateral brows. After injection, the augmented area was massaged with a roller to achieve a smooth upper forehead convexity. Botulinum toxin A at 8 i.u. (Botox, Abbvie) was also administered in the frontalis muscle on each side on follow up, and care was taken to avoid the lower third of the forehead to prevent eyebrow ptosis. Botox was chosen specifically, as it exhibits the narrowest diffusion radius and hence is least likely to cause unwanted brow ptosis [12]. At the 1-week follow-up, massage with a roller was repeated to ensure that smooth forehead convexity was maintained.

Modified classification of forehead and temporal patterns

A modified classification of forehead patterns was used for planning forehead augmentation as well as for counselling patients regarding the estimated volume of filler that was required. A system of forehead classification encompassing Types I to V was initially described by Kim et al. [12] and ranged from central forehead depression over the glabellar region (Type I) to an inclined sloping forehead pattern (Type V). As our study included temporal augmentation as part of the overall forehead rejuvenation, we added a modifier, T, to the classification. For example, if the patient possesses a central depression with a bilateral temporal volume deficit, they would be classified Type I+T (Fig. 2-6).

Figure 2. Type I+T forehead and temporal pattern illustrating central deficit over the glabellar region, lack of forehead projection and bilateral temporal deficits.

Figure 3. Type II+T forehead and temporal pattern illustrating bilateral supraorbital pattern deficit, lack of forehead projection and bilateral temporal deficits.

Figure 4. Type III+T forehead and temporal pattern illustrating confluent central glabellar region deficits, bilateral supraorbital pattern deficit, lack of forehead projection and bilateral temporal deficits.

Figure 5. Type IV+T forehead and temporal pattern illustrating confluent central glabellar region deficits, bilateral supraorbital pattern deficit, flattening of upper part of forehead and bilateral temporal deficits.

Figure 6. Type V+T forehead and temporal pattern illustrating confluent central glabellar region deficits, bilateral supraorbital pattern deficit, reclining of upper part of forehead and bilateral temporal deficits.

Assessment of satisfaction

Patients were assessed to determine whether they were satisfied with the results of their augmentation at the end of 24 months. Patients who were satisfied were recorded as “Satisfied”, while patients who were not were recorded as “Not satisfied”.

A total of 330 syringes of Ellanse M filler (1 ml/syringe) were used in this study of 86 patients, and this translated to an average of 5.9 syringes per patient for combined forehead, temple, and brow augmentation. The overall patient satisfaction rate was 78% (67 satisfied patients out of 86) at the 2-year follow-up mark. A total of 8 patients were lost to follow-up, and thus, the satisfaction rates were calculated based on intention-to-treat analysis. Most of our patients exhibited a Type IV+T classification that yielded a satisfaction rate of 40/47 (Fig. 7). The highest satisfaction rate was observed in the Type I+T, Type II+T, and Type III+T subgroups, with satisfaction rates at 90.9% to 100%. The greatest rate of dissatisfaction was observed in patients of Type V+T, with 25% (2/8 patients) dissatisfied (Fig. 7). There is a negative correlation between satisfaction between the higher subgroup IV+T and V+T of -0.96. (Fig. 8), where if the patient exhibited a higher forehead subtype, greater care and counselling was recommended to reduce patient dissatisfaction. There was no reported incidence of brow ptosis secondary to Botox diffusion.

Figure 7. Results of patient satisfaction for combined forehead and temporal augmentation and lateral browlift. Chart showing outcome of 86 patients who had received combined forehead and temporal augmentation as well as lateral browlift. A modified Type I to Type V +/- T classification was used to identify different forehead patterns. A satisfaction rate of 78% was achieved at the 2-year follow-up mark. 8 patients were lost to follow-up. The highest rate of satisfaction was registered in the Type I+T, Type II+T and III+T subgroup. A total of 11 patients were dissatisfied with the results of augmentation. The highest rate of dissatisfaction (2/8) was registered in the Type V+T subgroup.

Figure 8. Patient satisfaction versus classification of forehead and temporal pattern. Demonstrating negative correlation of -0.96 in patient with high subtype IV and V. In subgroup IV and V, greater volume of Ellanse collagen stimulator and pre-procedural counselling i.e., recommended to reduce patient dissatisfaction.

Safety

There was no reported incidence of hypersensitivity reactions to Ellanse. There was also no incidence of granuloma or nodules reported. Most importantly, there was no incidence of vascular complications such as blindness or tissue necrosis reported in this series. Swelling and bruising were noted in 20% of patients, and this lasted up to 2 weeks following the procedure. These side effects resolved with Arnika Forte tablets (Absolute MS [S]) and hirudoid gel application.

An aesthetically pleasing upper face that includes aesthetic subunits, and the forehead, temporal region, and eyebrows can contribute to the overall attractiveness of the face. Ellanse is a versatile polycaprolactone-based collagen stimulator that can be used for non-surgical forehead, temporal augmentation, and lateral browlift. It initiates Type I collagen production to achieve the eventual aesthetic result.

Our retrospective analysis of 86 patients demonstrated that Ellanse can be used for forehead and temporal augmentation and lateral browlift with great patient satisfaction and minimal complications. Our analysis indicated that the optimum volume of polycaprolactone filler required for forehead, temple, and lateral browlift augmentation is approximately 5.9 ml and that the overall rate of patient satisfaction is 78% (67/86). The results were analyzed using the intention-to-treat approach. The highest rate of dissatisfaction was recorded in the Type V+T forehead pattern subgroup. One of the underlying reasons could be the presence of a greater degree of forehead deficit (Type V+T is characterized by greater flattening of the forehead and hollowing of the temple, and hence, a greater volume of polycaprolactone filler may be required). This may also indicate the greater complexity involved in rejuvenating foreheads of higher subtypes due to the greater amount of Ellanse required.

An interpretation of this analysis was that our modified system of classification could be helpful for estimating the quantity of polycaprolactone filler required for satisfactory forehead and temporal augmentation. Additionally, our analysis assisted in identifying the group of patients with the greatest deficit (Type V+T) and consequently the highest rate of dissatisfaction with the result.

A common initial reaction among patients upon hearing that 6 vials of filler will be used is “Will I look weird, doctor?” However, as we have demonstrated in our study, an average of 5.9 vials of polycaprolactone filler is required for a symmetrical, aesthetically pleasing forehead with adequate projection to achieve a smooth convex appearance (Fig. 9). Additionally, polycaprolactone filler is required to perform lateral browlifts and temporal augmentation. The combination of using a simple classification of forehead and temporal patterns with a detailed explanation of the intended effects of augmentation is often helpful in allaying patient fears regarding overfilling.

Figure 9. (A) Frontal: forehead and temporal augmentation and lateral BrowLift with Ellanse M (at 24 month follow up). (B) Oblique: forehead and temporal augmentation and lateral BrowLift with Ellanse M.

In the process of subsequent follow-ups, additional botulinum toxin A treatment was often necessary for treating horizontal wrinkles. Botox was selected in our series due to its relatively small diffusion radius.

There was no reported incidence of vascular compromise or nodule formation in the case series. The reason was attributed to the strict adherence to supraperiosteal injection of Ellanse filler (Fig. 1) to stimulate neocollagenesis deep to the frontalis muscle.

Complication management

To minimize complication, a thorough understanding of anatomy, particularly of the facial danger zones, was crucial. Physicians must be prepared to act quickly and to recognize key signs such as pain or skin discoloration that call for an immediate halt of the procedure and prompt initiation of complication management. Recommended initial treatments included topical nitroglycerin paste under an occlusive dressing, oral acetylsalicylic acid (aspirin), warm compresses, and vigorous massage. If primary interventions were not sufficient, secondary treatments may include hyperbaric oxygen therapy and vasodilators such as prostaglandin E1 [13].

Limitations

The research was limited by the retrospective nature of the study, and a prospective study would be beneficial to validate the results. Additionally, for Type IV+T and Type V+T subgroups, further analysis is required to determine if this group of unsatisfied patients may benefit from a greater volume of polycaprolactone filler or if they may instead benefit from other modalities of forehead and temporal augmentation such as fat or hyaluronic acid filler.

In summary, Ellanse is a versatile filler that can be used effectively with Botox for non-surgical forehead and temporal augmentation as well as lateral brow lifting. A simple modified classification of forehead and temporal patterns was devised to assist in patient counselling and predicting the amount of polycaprolactone filler required. Most importantly, there was no reported incidence of vascular compromise or nodule formation.

Joy Lee for image preparation and Adam Chua for graphics. Karen Chong for editorial support. Dr. GuoQing Chen of UESTC for anatomic technical support.

None.

The authors have nothing to disclose.