Could firmness under the eyes be caused by old filler?
Some people are concerned when they feel a firm area or small lump under their eyes that was not there before.
If you have previously had filler injected under the eyes or into the anterior cheeks, you may wonder whether old filler is still present.
Hyaluronic acid fillers generally break down over time, but they may persist longer than expected depending on the product's physical properties, the amount and location injected, repeated treatments, and the individual's tissue condition.
However, feeling a firm area under the eyes alone does not establish that old filler is the cause.
Residual filler may form a palpable clump, but fibrosis or adhesions around the filler, inflammatory reactions, or nodules may also contribute.
Causes unrelated to filler, such as cysts in the skin or subcutaneous tissue, scar tissue, or changes in fat and surrounding structures, can produce similar symptoms.
Rather than judging the cause from a history of filler injections alone, it is important to assess comprehensively whether material suspected to be filler remains, its depth, and any changes in surrounding tissue.
Why old under-eye filler may feel firm
Even if there were no particular problems immediately after treatment, under-eye filler may later feel like a firm area or lump.
If filler is concentrated in one area, unevenly distributed, or located in a superficial layer close to the skin, its edges may be palpable.
Particularly after repeated injections in the same area or relatively large volumes, the possibility of filler remaining at different depths and locations should be considered.
MRI studies have also observed cross-linked hyaluronic acid filler in the midface for longer than is commonly expected.
In a study of 33 participants published in 2024, MRI signals interpreted as hyaluronic acid filler were found in all participants at least 2 years after their last treatment, and in some participants for longer periods.
However, this small study examined cross-linked hyaluronic acid fillers injected into the midface, so its findings cannot be applied equally to all filler products and all patients.
Even without obvious visible changes, residual filler or changes in surrounding tissue may cause firmness, a foreign-body sensation, recurrent swelling, or contour irregularities.
Adhesions and fibrosis around filler
Firmness associated with old under-eye filler does not always arise from the filler itself.
Adhesions and fibrosis may develop at an injection site depending on individual tissue reactions or previous inflammation.
Adhesions occur when tissues that originally moved smoothly against one another become attached through inflammation or healing, restricting movement.
Fibrosis refers to an increase in fibrous tissue, including collagen, during healing that makes an area thicker or firmer than normal tissue.
In some cases, fibrous tissue may form around residual filler.
However, these changes do not occur with every old filler, and firmness alone cannot establish whether a capsule or fibrosis has formed.
After repeated filler treatments or a previous inflammatory reaction at the site, the tissue around the filler may differ from its condition at the initial treatment.
Adhesions and fibrosis may occur separately or together. These changes may cause a broader area of firmness or more restricted movement than residual filler alone.
The area may look relatively normal at rest, but a particular spot may become more prominent when smiling or contracting the muscles around the eyes, movement under the two eyes may differ, or the under-eye contour may appear uneven.
What is a filler nodule that feels like a hard lump?
A round, firm area or small bead-like lump under the eye may suggest a filler-related nodule.
A nodule is a term describing a localized palpable lump at a filler injection site.
The term itself does not identify a single cause or establish a histological diagnosis.
It may simply be a localized collection of filler, or it may result from surrounding fibrous tissue, an inflammatory reaction, infection, or a foreign-body granuloma.
Some noninflammatory nodules are palpable with relatively little pain or redness, while inflammatory nodules may involve redness, warmth, pain, or recurrent swelling.
Therefore, a palpable nodule alone should not determine the cause or lead to the same treatment in every case. Its onset, changes in size, pain, warmth, skin color changes, and swelling must also be assessed.
Nodules vary in size and shape. Some feel like tiny granules, while others are more distinct, bean-sized lumps.
When surrounding fibrosis or adhesions are present, they may feel like a broad, firm area without clear borders.
Why filler changes are more noticeable under the eyes
The skin and soft tissue under the eyes are relatively thin compared with other facial areas, making small changes beneath the skin easier to see or feel.
In areas with relatively thicker soft tissue, such as the cheeks or temples, slight filler clumping or changes in position may be less noticeable.
Under the eyes, however, filler close to the skin or concentrated in one spot can make its edges or unevenness relatively visible.
The muscles and tissue around the eyes also move repeatedly during blinking, smiling, frowning, and other expressions.
Even if the area looks relatively smooth at rest, differences in movement between the filler-containing area and surrounding tissue when smiling or contracting the muscles around the eyes may make a particular area protrude.
The degree of existing under-eye fat protrusion, tear trough depth, and anterior cheek volume also affect the under-eye appearance.
If filler remains alongside protruding under-eye fat, the area may look fuller overall even when the actual amount of filler is small.
Conversely, loss of surrounding fat and volume may reveal filler edges or clumps that were previously unnoticeable.
Evaluation of old under-eye filler should therefore consider not only its possible persistence but also its depth and distribution, under-eye fat and tear trough anatomy, and changes in surrounding tissue.
How is under-eye firmness assessed?
First, the filler ingredient and product name, number of treatments, and date of the last treatment are reviewed.
If you cannot recall the exact product name, reviewing medical records or product information from the treating clinic may help.
The assessment then covers when the firm area first appeared, changes in size, recurrent swelling, pain, redness, warmth, and skin color changes.
Differences in shape or movement at rest and during facial expressions are also assessed.
If examination alone cannot clearly distinguish the cause, imaging such as ultrasound may help assess the location, depth, and distribution of material suspected to be residual filler and its relationship to surrounding structures.
However, imaging alone cannot always establish the exact composition of previously used filler or the full extent of adhesions and fibrosis.
Current symptoms, examination findings, treatment history, and imaging results must be considered together.
If inflammation, infection, or a foreign-body granuloma is suspected, or the diagnosis is uncertain, the clinician may consider pathological or microbiological testing of sampled material or tissue.
Does all old filler need to be removed?
The presence of residual filler does not necessarily mean it must be removed.
If there are no symptoms such as pain or recurrent swelling and no concern about appearance, observation may be appropriate depending on the current condition and filler type.
However, persistent firm lumps, recurrent swelling, pain, a foreign-body sensation, asymmetry, or uneven contours warrant assessment of the cause before deciding whether treatment is necessary.
Treatment may vary depending on the filler composition and location, symptom type, presence of inflammation or infection, and condition of surrounding tissue.
Can filler-dissolving injections alone resolve the problem?
For hyaluronic acid fillers, treatment to break down the filler with hyaluronidase may be considered.
However, depending on the amount, location, and distribution of filler, one injection may not provide sufficient improvement and additional treatment may be needed.
Hyaluronidase is an enzyme that breaks down hyaluronic acid; it does not eliminate all fibrous tissue or adhesions already formed around the filler.
If the filler composition is unknown or a non-hyaluronic acid substance was injected, hyaluronidase may not break it down.
In addition, pain, warmth, redness, marked tenderness, or sudden swelling requires assessment for inflammation or infection first.
In these circumstances, the cause should be distinguished before deciding the treatment sequence and approach, rather than proceeding directly with filler dissolution.
Symptoms that warrant medical evaluation
If the following changes occur, it is advisable to seek medical evaluation rather than wait on the assumption that you are simply feeling old filler.
- The palpable area gradually enlarges
- Redness, warmth, or tenderness accompanies the lump
- Under-eye swelling recurs or suddenly worsens
- Changes in under-eye shape persist alongside a firm area
- The skin becomes thinner, or pus or discharge appears
If the skin turns white or blue, or severe pain, blurred vision, double vision, or reduced vision develops after a recent filler injection, a vascular complication cannot be excluded. Immediate assessment at the treating clinic or an emergency medical facility is required.
Frequently asked questions
Q. Can filler injected a long time ago still remain?
A. Yes.
Hyaluronic acid fillers generally break down over time, but they may persist longer than expected depending on the product's physical properties, the amount and location injected, repeated treatments, and the individual's tissue condition.
However, not all fillers break down in the same way. If the composition is unknown or a non-hyaluronic acid substance was used, its persistence and treatment may differ.
Therefore, a long interval since treatment does not establish that all filler has disappeared.
Q. Does firmness under the eyes always mean filler?
A. No.
Residual filler itself may be palpable, or the cause may be filler clumping, adhesions or fibrosis in surrounding tissue, or an inflammatory reaction.
Causes unrelated to filler, such as cysts in the skin or subcutaneous tissue or scar tissue, may produce similar symptoms and require examination to distinguish them.
Q. Does all old under-eye filler need to be removed?
A. Residual filler does not necessarily need removal.
If there are no particular symptoms or concerns about appearance, observation may be appropriate depending on the condition.
However, if firm lumps, recurrent swelling, pain, a foreign-body sensation, asymmetry, or uneven contours persist, the filler location and surrounding tissue should be assessed before deciding whether treatment is necessary.
With older filler, the current condition under the eyes matters.
Under-eye firmness may result from residual old filler, but filler clumping, surrounding adhesions and fibrosis, nodules, and inflammatory reactions may also contribute.
Particularly after treatment long ago or repeated injections, the original treatment information alone may be insufficient to judge the current condition.
Because under-eye skin and soft tissue are thin and move repeatedly with facial expressions, even small changes can be readily visible or palpable.
If firm lumps, recurrent swelling, pain, a foreign-body sensation, or unevenness persist, assessment of possible residual filler, its location, and surrounding tissue can help determine whether a suitable treatment is available.
If lumps, firmness, recurrent swelling, or a foreign-body sensation persist after under-eye filler treatment performed long ago, you can request a medical consultation with UVOM Plastic Surgery at 02-545-3700 or via KakaoTalk at 'UVOM Plastic Surgery'.
※ Diagnosis and treatment may vary depending on filler composition and location, surrounding tissue condition, and individual symptoms.