Why We Combine Intramuscular and Subglandular Fat Grafting

Fat grafting breast augmentation uses the patient’s own fat to create a natural increase in breast volume.

Because it does not rely on silicone implants, it can achieve a soft and natural texture.
However, one of the most important factors that determines the final result is:

Which layer the fat is injected into.

Fat grafting breast augmentation is not simply about how many cc are injected.
The result depends on where the fat is placed, how much is injected into each layer, and how evenly it is distributed.

The Pectoralis Major Muscle Is One of the Best Layers for Fat Retention

In fat grafting breast augmentation, one of the areas where fat tends to survive well is the pectoralis major muscle.

The pectoralis major muscle has a rich blood supply.
This provides a favorable environment for the injected fat to receive oxygen and nutrients.

On ultrasound examination after surgery, we can sometimes observe fat remaining within the muscle in a finely distributed pattern, similar to marbling in beef.

This is one of the reasons why intramuscular fat grafting is considered important for fat retention.

However, Injecting Only Into the Muscle Is Not Always Ideal

Some patients may think:

“If fat survives well in the muscle, why not inject everything there?”

However, that is not always the best approach.

In patients with:

• Thin skin
• Thin breast gland tissue
• Limited natural breast fat
• A slim body type with little soft tissue in the décolletage

injecting too much fat only into the pectoralis major muscle may make the chest look firm, thick, or muscular rather than soft and feminine.

In fat grafting breast augmentation, fat retention is important, but it is not the only goal.
The result must also look natural, soft, and aesthetically balanced.

Subglandular Fat Grafting Helps Shape the Breast

Fat grafting into the subglandular layer is extremely important for shaping the breast.

Appropriate fat placement under the breast gland can help:

• Create a rounder breast contour
• Smooth the transition from the décolletage to the breast
• Add volume near the cleavage
• Improve asymmetry
• Create a softer appearance

If intramuscular fat grafting is the layer for better retention, subglandular fat grafting is the layer for creating shape.

AVAN TOKYO’s Preferred Balance

Subglandular : Intramuscular = Approximately 1 : 1

At AVAN TOKYO, we place great importance on balancing subglandular and intramuscular fat grafting.

As a general guideline, we often aim for a ratio of:

Subglandular : Intramuscular = approximately 1 : 1

This allows us to aim for both fat retention and beautiful breast shape.

The intramuscular layer supports retention.
The subglandular layer helps refine roundness, softness, and natural contour.

By combining these two layers appropriately, we aim to achieve both long-lasting volume and aesthetic beauty.

Case Example: Arm Liposuction and Fat Grafting Breast Augmentation, 6 Months Post-Operative

This case shows a 6-month post-operative result after arm liposuction and fat grafting breast augmentation.

At 6 months, swelling has settled, and it becomes easier to evaluate fat retention and breast contour.

Ultrasound examination confirmed fat remaining within the pectoralis major muscle in a finely distributed pattern.

This allows us to evaluate not only the external appearance, but also how the grafted fat has survived internally.

Why Arm Liposuction and Fat Grafting Breast Augmentation Work Well Together

Arm liposuction and fat grafting breast augmentation are an excellent combination.

By removing excess fat from the arms:

• The arms become slimmer
• The shoulder-to-arm line looks more delicate
• The upper body appears more refined
• The breasts stand out more beautifully

That harvested fat can then be used to enhance the breasts, helping create:

• Natural breast volume
• A soft texture
• Better body harmony using the patient’s own fat

This makes it possible to pursue the ideal upper body balance:

Slimmer arms and naturally fuller breasts.

Fat Grafting Is About Layer Design, Not Just Volume

A common misconception is that injecting more fat automatically creates a better result.

In reality, excessive fat injection in one session may increase the risk of:

• Lumps
• Fat necrosis
• Calcification
• Lower retention rate
• Unnatural firmness

What matters is not only the volume, but also:

• Which layer the fat is injected into
• How widely it is distributed
• Where volume should be added
• How naturally the contour is connected

At AVAN TOKYO, we treat the breast as a three-dimensional structure and design fat grafting layer by layer.

AVAN TOKYO’s Approach to Fat Grafting Breast Augmentation

At AVAN TOKYO, fat grafting breast augmentation is not simply a size-enhancement procedure.

We design the entire upper body, including:

• Natural breast contour
• Soft texture
• Symmetry correction
• Smooth transition from décolletage to cleavage
• Balance between subglandular and intramuscular injection
• The contour of donor areas such as the arms or thighs

We do not look at the breasts alone.
We design the entire body line, including where the fat is harvested from.

Final Message

Fat grafting breast augmentation is not just about injecting fat.

The result depends on:

• Where the fat is injected
• How much is injected
• How the breast shape is created
• How naturally the result blends with the body

The pectoralis major muscle is an important layer for fat retention, but relying only on that layer is not enough.

By combining intramuscular and subglandular fat grafting, we aim to achieve both better fat retention and a beautiful, natural breast contour.

At AVAN TOKYO, we combine arm liposuction and fat grafting breast augmentation to create a refined upper body with slimmer arms and naturally fuller breasts.