English edition

foreign-body

Most people who arrive for a foreign body removal have already been told the problem is small. They have had a dissolving injection, or two. They have had a course of steroid, and the lump went quieter for a while. The complaint is still there. By the time the material is examined properly it is rarely sitting in a neat pocket. It has spread through more than one plane, scar has formed around it, and the line between it and normal tissue has stopped being obvious.

01What the word covers

Foreign body is a broad term, and it has to be. It is used here for anything injected or placed into the face that is still present and is causing trouble: pain, inflammation, a firm nodule, a visible lump, discolouration showing through thin skin, skin that has thinned or broken down, or a shape that has drifted away from where it started.

The materials fall into groups, and the group matters more than the brand name.

Hyaluronic acid fillers

Gels based on hyaluronic acid. These are the materials an enzyme can act on. They are also the ones most often assumed to have gone when they have not.

Semi-permanent and non-HA fillers

Calcium-based, poly-L-lactic acid, polycaprolactone-based and collagen-based products. The clinic names Radiesse, Ellansé, Artecoll, Artefill, Sculptra and Aquamid among the materials that generally require a surgical route rather than an enzyme.

Permanent materials

Silicone, paraffin and industrial-grade material injected outside a medical setting. These often occupy several planes at once and are bound into the tissue that has formed around them.

Grafted fat

Transferred fat that has survived unevenly, hardened, calcified, formed oil cysts, or settled somewhere other than where it was placed. Calcified graft can read as bone shadow on CT.

Lifting threads

Thread material and the fibrous tissue that has formed along its track. The thread may have partly absorbed while the tissue reaction to it has not.

Injectables of unknown composition

Material injected years ago with no record of what it was. A missing product name does not prevent assessment. It does change what may be assumed, and it rules out shortcuts.

A single face may hold more than one of these. Someone who had hyaluronic acid at twenty-five, a semi-permanent filler at thirty and fat grafting at thirty-four arrives with three problems in the same cheek, at three depths, of three different ages, and they do not behave alike.

02Why a lump can appear years after the injection

A common history is that nothing happened for a long time. The injection was five years ago, or nine. It settled. There was no problem. Then a firm nodule appeared, and it has not gone.

A foreign body reaction is slow. The body recognises the material as foreign and mounts a response that continues at low level for as long as the material is present. Collagen forms around it. Macrophages fuse into multinucleated giant cells. Over years this accumulates, and what accumulates is firm. The clinic describes delayed inflammatory nodules appearing anywhere from a few weeks to more than a year after an injection, and describes multinucleated giant cells and collagen deposition on pathology after removal of semi-permanent filler.

Collagen-stimulating products are the group in which this is most often described. They are designed to provoke collagen. Where more collagen forms than was intended, the result is a hard mass rather than a soft correction.

A delayed reaction and an infection are not the same event and do not behave the same way. Infection tends to be acute, with redness, heat and pain developing over days. A foreign body reaction tends to be slow and firm. The two can occur together, which is one reason the examination carries more weight than the history.

03Why dissolving is not a universal answer

Hyaluronidase is an enzyme. It hydrolyses hyaluronic acid and it does that well. What it does not do is act on materials that are not hyaluronic acid.

Polycaprolactone-based products such as Ellansé are not broken down by it. Calcium-based and collagen-based materials behave differently again. The carrier gel may disperse while the particles, and the collagen the body has built around them, stay where they are. The face feels slightly softer for a few weeks and then returns to what it was.

This matters most when the injection is being used as a test. A response suggests hyaluronic acid was present. No response does not identify the material. It only makes hyaluronic acid less likely. The response is treated as one piece of information among several, never as a diagnosis on its own.

Steroid is the other common intermediate step. Injected or taken by mouth, it can reduce the inflammatory reaction around a material and can reduce the bulk of the nodule that reaction has produced. It does not remove the material. When the course ends, the material is in the same plane it was in, and the tissue around it has usually been altered again by the treatment itself. A reduction in inflammation and bulk is not the same event as removal. The distinction is worth insisting on before a third or fourth round is agreed to.

None of this is an argument against trying an enzyme first. Where the history and the examination point clearly to hyaluronic acid, the clinic does not hurry to operate. A dissolving injection is the smaller intervention and it is tried before a surgical one. The argument is against continuing with it once it has been tried and has not worked.

04Establishing what is there, before deciding anything

Assessment begins with the examination and with ultrasound. Ultrasound shows the position of the material, its depth, whether it has formed discrete nodules, whether there is fluid, and how it sits in relation to the tissue around it. It shows this in real time, without radiation, and it can be repeated as often as needed. It is also used during the operation.

It has a limit. Ultrasound does not reliably name a product. Old mixtures, and tissue that has become widely fibrotic, produce overlapping patterns, and two different materials of the same age can look much alike. Recent, localised material is easier to characterise than material that has been in place for a decade.

CT is added when the question involves bone: the position of the bone beneath the material, calcification spread over a wide area, or the traces of previous contouring surgery. It is not taken as a routine, and where the material is confined to soft tissue it is usually not needed.

1. Examination and history, including what is known and what is not known about what was injected and when.
2. Ultrasound, to map position, depth, nodularity and the relationship to normal fat, muscle and nerve.
3. A hyaluronidase response, where hyaluronic acid is plausible and has not already been excluded.
4. CT, where bone position, wide calcification or previous contouring surgery needs to be seen.
5. Histology, where imaging and response leave the nature of the reaction unclear, or where a foreign body reaction needs confirming.

Not every step is used in every case. Most plans are made from the examination and the ultrasound alone.

05Four ways in, and why the route is chosen before the first incision

The clinic describes four removal routes. The choice rests on three things: how hard the material is, how firmly it has bound to the tissue around it, and where it sits.

One region often needs more than one of them. A cheek holding soft material in the superficial fat and a hard nodule against the bone is treated by two different approaches in the same operation. These are not competing methods. They are instruments chosen for what is in front of them, and the choice can change once the plane is open.

The endoscope deserves its own sentence. In the forehead, glabella and temple the supraorbital, supratrochlear and temporal branches run close to where old material tends to settle. Magnified vision through a scalp incision allows the plane to be followed under direct view and keeps the visible scar off the face. The temporal endoscopic approach used at the clinic was developed by its founding director, Dr. Jung Su Lee.

06The operation, in sequence

1. Sedation, with local anaesthetic infiltration of the field. The clinic’s stated protocol is sedation rather than general anaesthesia for most regions.
2. The mapped plane is entered through the access chosen for it: a cannula entry point, a scalp incision for the endoscope, or a direct incision over the material.
3. The material is separated from normal tissue under vision or under ultrasound, working outward from where the boundary is clearest toward where it blurs.
4. The boundary is judged continuously. Colour, texture and degree of adhesion are read alongside what the ultrasound showed and what could be felt before the operation.
5. Nerve and vessel are identified where the anatomy allows and left intact. Material adherent to them is treated as material to be reduced, not material to be chased.
6. The cavity is inspected and irrigated. Drainage is used where the dissection has been wide.
7. Closure is in layers. A scalp incision is closed within the hair; an external incision is closed with fine suture.

Removed material is sent for histology where the nature of the reaction is in question. The clinic describes pathology after removal of semi-permanent filler showing multinucleated giant cells and collagen deposition around the material.

07How much comes out

Complete removal is not the objective, and saying so plainly is more useful than implying otherwise.

Material that has been in place for years is not a discrete object. It has provoked a tissue response. Collagen has formed around it, and in places it has become continuous with normal fat. Removing everything that might be material means removing normal fat, and in some places the nerve running through it. The clinic’s stated principle is that normal tissue is preserved, and that surgical removal therefore cannot be complete.

The aim is not the volume removed. It is the reduction of the part producing the symptom.

The clinic’s stated operating principle

In practice this sets two working rules. What can be felt, and what corresponds to the symptom, is reduced. What cannot be felt, produces nothing and lies against a nerve is left alone.

Telling material from normal fat

The boundary is not read from a single source. Palpation comes first, and the rule attached to it is conservative: what cannot be felt is not pursued. Ultrasound adds what the hand cannot reach, separating discrete nodules, oil cysts, calcification and fluid change from the fat around them. Calcified grafted fat can appear as bone shadow on CT. During the operation, colour, texture and the degree of adhesion are read together, an oil cyst being firm to the touch and oily when opened.

Old material makes all three harder to interpret. As fibrosis advances, differences in colour and texture flatten and the material becomes continuous with the tissue holding it. Where the boundary is genuinely uncertain and a nerve runs through it, the decision falls toward preservation. Where the symptom clearly originates there, more is accepted. An error in one direction leaves hollowing or a damaged nerve. An error in the other leaves the symptom in place. Histology is used where the nature of what came out remains in question.

Staging follows from the same reasoning. Where material has spread through several planes, or where inflammation is still active, a first operation reduces the part causing most trouble and the remainder is reassessed once the tissue has settled. Staging is a decision taken in advance, not a failure to finish.

Material left behind is not the same as a problem left behind. Material producing no symptom may simply be watched. If symptoms return, the situation is reassessed and further removal considered then, on what the tissue looks like by that point.

Operative information, as the clinic describes it

Anaesthesia

Sedation

Operating time

60 to 120 minutes, by region

Removal routes

Cannula aspiration, ultrasound-assisted, endoscopic, open incision

Assessment

Ultrasound, with CT where bone or wide deformity is in question

Swelling peak

48 to 72 hours after surgery

Sutures removed

5 to 7 days

Main recovery

About one week

Tissue settling

Up to six months

08Recovery

Swelling increases for the first two to three days and is usually at its worst on the second. It then settles gradually. Sutures come out at five to seven days, and most people return to ordinary activity from about a week.

Bruising is the variable part. Where it is marked it can take two weeks or more to clear. The slower element is the tissue itself. Scar forms where material has been separated from it, and scar is firm before it is soft. Firmness, small irregularities and areas that feel tethered are common in the early months and change slowly. The clinic asks for up to six months before the result is judged, which is longer than most cosmetic operations require.

That interval matters for a second reason. Judging whether enough material has been removed, in the first weeks, is judging swelling. Where a further removal is being considered, it is considered after the tissue has settled, not before.

09What this operation cannot do

• It cannot remove all of the material. Where material is bound to nerve, vessel or normal fat, part of it is left deliberately.
• It cannot guarantee that a delayed inflammatory reaction will not recur. Where material remains, a reaction to it can return.
• It cannot restore volume. A space occupied for years is a space once the material leaves, and skin stretched over it stays stretched.
• It cannot identify a product retrospectively with certainty. Histology describes the tissue reaction. It does not always name what was injected a decade ago.
• It cannot eliminate the risk of nerve injury, skin necrosis, infection, asymmetry, contour irregularity or recurrence. The dissection runs through tissue that has already been altered once.

10What is left behind when material leaves

A face that has carried injected material for years has adapted to it. The skin over it has stretched. Deeper support has often been displaced by the volume resting on it. Where a forehead implant has been in place a long time, the clinic describes erosion of the bone beneath it, so that removal reveals a hollow that was not visible while the implant was in.

This is anticipated rather than discovered. CT and ultrasound show how much material there is and what lies under it, and the likely appearance after removal is discussed before the operation rather than explained afterwards.

Correction is sequenced. The clinic’s stated recommendation is autologous fat grafting from about six months after removal, and ultrasound-based tightening from about three months. Where laxity rather than hollowing is the main problem, a lift is considered instead: forehead lift, facelift or thread lift, according to where the tissue has descended.

Whether removal and lift happen on the same day is decided on inflammation, on the extent of the dissection each requires, and on the blood supply of the skin that would be raised. Localised material with settled inflammation may allow both in one operation. Active inflammation, widely distributed material or compromised skin perfusion argue for separating them, and the interval between them is set by how quickly the tissue settles rather than by a fixed rule.

11Who this operation is not for

• People with active infection. Inflammation is settled first, with medication, and the removal is planned after that.
• People whose material is confirmed or strongly suspected to be hyaluronic acid and who have not yet had a dissolving injection. The smaller intervention is tried first.
• People with no symptoms who want complete removal for its own sake. The risk and the benefit are discussed again before anything is planned.
• People whose material is spread very widely through several planes and bound to normal fat and nerve. Staged, conservative removal is usually safer than an attempt at a single complete clearance.
• Material under the eye, which is judged against a different standard. The lower eyelid is described separately.

The clinic lists Dr. Chang Min Kang as the doctor for facial and under-eye foreign body removal. Where a face carries both a bone problem and a soft-tissue problem, as is common after previous contouring surgery, the two directors may review the plan together. Which of them conducts the consultation and the operation is confirmed at the clinic.

No. Removal is carried out while preserving normal tissue, so complete clearance is neither the aim nor achievable where material has bound to nerve, vessel or normal fat. What is removed is decided by what is producing the symptom and by what can be separated safely. An endoscope or direct vision widens what can be reached, because adherent material can be worked on under sight, but it does not change the principle.

In regions dense with nerves: the forehead, the glabella and the temple. The magnified view is used to follow the plane and to reduce the chance of nerve injury, and the incision sits inside the hairline, which keeps the scar off the face.

Where the material is confined to soft tissue, ultrasound is usually enough. CT is added when bone position, wide calcification or the traces of earlier contouring surgery need to be seen. It is not taken as a matter of routine.

The clinic’s stated pattern is that swelling increases for the first two to three days, is worst on the second, and then settles. Sutures come out at five to seven days and most people return to ordinary activity from about a week. Firmness in the tissue takes considerably longer, and up to six months is normal.

No. The skin of the lower eyelid is the thinnest on the face, and more structures have to be preserved there than anywhere else. Under-eye removal is judged against its own standard and is described on a separate page.

ReferencesKang CM, Shim JS, Park SH, Jeong YJ, Seol KH, Kwak SG. Volume Change of Muscle and Fat Portions of Latissimus Dorsi Myocutaneous Flap after Breast Reconstruction. Plast Reconstr Surg Glob Open. 2021;9(4):e3536.PMID 33868878Sixteen patients after breast reconstruction. Muscle and fat were measured as separate components and changed at different rates. Cited here only as background to the habit of measuring tissue by layer and by component. It is not evidence about facial surgery.Kang CM, Shim JS. Volume Change of Pedicled Latissimus Dorsi Muscle Flap after Partial Breast Reconstruction. J Reconstr Microsurg. 2018;34(8):651-657.PMID 30099736Eleven patients, followed on CT for five years after partial breast reconstruction. The study population is breast reconstruction. Cited as methodological background only.UVOM Plastic Surgery, procedure information for facial foreign body removal.The clinic’s own description of its assessment, its four removal routes and its operative information. It is the clinic’s stated protocol, not peer-reviewed evidence.ContinueRemovalUnder-eye RemovalThe lower eyelid is the thinnest skin on the face and the place where the most has to be left behind. This page sets…RemovalKnowing What Is In ThereMost people arrive without a product name, a receipt or a record. Identification begins instead with what can still…RemovalHow Much Comes OutOpening is not the difficult part of a removal. The difficult part is deciding, against the anatomy actually in…