Ultrasound-Guided Injection
Before injecting in vessel-rich regions I image the course of your vessels with ultrasound — using a high-resolution linear probe of 8 to 20 megahertz with colour Doppler. The 2025 international expert consensus names at least 15 megahertz as the minimum requirement. Vascular anatomy is individual; average values say little about your face. The method comes from anaesthesiology, where needle guidance under ultrasound is part of the craft.
Method · Safety in facial injections
Ultrasound-Guided Injection
You have read up on fillers — and got stuck on the stories you would rather not have seen. That concern is reasonable. So I look before I treat: your vessels on the screen before the needle goes in. You watch with me.
In short
In an ultrasound-guided injection, the treatment area is imaged with high-resolution ultrasound before and during the injection. This shows the course of vessels, the tissue layers and any filler material already present. The needle or cannula can then be guided under vision rather than by palpation and anatomical rule. In 2025, an international expert panel of fifteen specialists from seven medical disciplines and eleven countries defined, in a four-round Delphi process, which facial regions call for this approach, which equipment is sufficient and what a practitioner must be able to do.
The question few patients ask out loud
What if something goes wrong with me?
Most women who come to me have done their research. They have seen images they wish they had not. And they ask a question, often only at the end of the conversation: what if something goes wrong with me?
I take that question seriously. Not to frighten you — but because it is legitimate. An injection in the face is a medical procedure. Anyone who presents it otherwise is selling you something.
What I can do about it is look. Not guess, not palpate alone, not rely on experience alone — but see on a screen where your vessels actually run.
In anaesthesiology I have been guiding needles under ultrasound for years — placing central lines and performing nerve blocks. There it is part of specialist training, not optional equipment. You hit what you see.
— Dr. med. Thomas Ackermann · Consultant Anaesthesiologist
Why anatomy alone is not enough
Textbooks describe the average
Every injection curriculum rests on anatomical rules: this vessel runs there, that layer lies here. Those rules hold — for the average.
How far reality departs from it was measured for the forehead in an ultrasound-based study by Cotofana and colleagues. In women, the distance from the supratrochlear artery to the vertical glabellar line averaged 8.2 millimetres. The range extended from 14.2 millimetres to minus 3.3 millimetres.
The negative value is the decisive finding. It means that in some of those examined the artery runs on the other side of the line — precisely where the anatomical rule sends the needle.
This is not an argument against anatomical knowledge. It is an argument for looking in the individual case.
Equipment
What the international consensus requires
The 2025 Delphi paper is the first to state concrete minimum requirements for equipment. That makes it possible to check objectively whether a practice runs this method seriously or merely mentions it. The table below places both side by side.
| Requirement | Consensus recommendation 2025 | In this practice |
|---|---|---|
| Transducer | Linear probe of at least 15 MHz — both for learning and for routine diagnostics | Linear probe with a frequency range of 8 to 20 MHz |
| Device format | Hand-held devices are explicitly permitted in both settings | Wireless hand-held device, usable directly at the treatment chair |
| Imaging modes | B-mode, colour Doppler and spectral Doppler mandatory; power Doppler recommended | B-mode, colour and power Doppler available |
| Penetration depth | A few centimetres are sufficient for facial structures | Up to 4 centimetres — covers all relevant facial layers |
| Documentation | Picture and video archiving mandatory | Images stored as part of the treatment record |
| Sterile technique | Sterile probe cover and sterile gel required for guided injection | Sterile material kept in stock |
| Prior findings | Existing filler material should be identified before injecting | A fixed part of the examination, including treatments performed elsewhere |
Source: Velthuis PJ et al., J Plast Reconstr Aesthet Surg 2025;104:33–37 (PMID 40101353). Full references below.
Putting the numbers in context
Why a higher frequency is not automatically better
Ultrasound obeys a physical trade-off that cannot be circumvented: the higher the frequency, the finer the resolution — and the shallower the penetration. A very high-frequency probe displays the uppermost millimetres of skin superbly and reaches the deeper fat compartments and the arteries running beneath them less well.
For the questions that matter in injectable work — where does this vessel run, in which layer does this deposit sit, is this nodule vascularised — the useful working range therefore lies in the mid to upper band. That is exactly where the consensus sets its lower limit of 15 MHz.
What follows from this
The number on the datasheet does not decide the examination
A device with an even higher frequency does not produce better diagnostics if the examiner cannot reliably tell filler material, tissue layers and vessels apart in the image. The consensus devotes more space to competence than to technology and lists what a practitioner must master before starting. I consider that order correct: the device is a prerequisite, the practice is the achievement.
Three applications
When I use ultrasound
Not every treatment needs imaging. In these three situations I consider it worthwhile.
Before injections in vessel-rich areas
Temple, forehead, nasal dorsum, tear trough and jawline are regions with densely running arteries. Here I image the vessels before injecting and plan the route along your anatomy — not along a diagram. The consensus regards pre-injection imaging in areas at high risk of vascular events as mandatory.
When dissolving hyaluronic acid
Hyaluronidase works where it arrives. If the deposit is localised on ultrasound, the enzyme can be placed precisely instead of being distributed broadly. That spares the body's own hyaluronic acid in the surrounding tissue. For precise intralesional injections the consensus names ultrasound guidance as necessary.
For botulinum toxin type A in deep muscle groups
At the masseter and the platysma the target muscles lie deeper and vary considerably between individuals in thickness and extent. Sonographic imaging helps adapt the injection depth to the individual finding rather than assuming a standard depth.
When dissolving
Why the enzyme dose comes out smaller
There are two approaches to dissolving hyaluronic acid: distributing the enzyme broadly through the tissue — described in the literature as flooding — and injecting it directly into the imaged deposit.
A group around Schelke compared both in 39 patients who were first treated by flooding and subsequently under ultrasound guidance. The ultrasound-guided protocol used a mean of 122.5 international units of hyaluronidase, the flooding protocol 1,519 units. Symptoms also resolved faster in the ultrasound-guided group.
How solid is this? It is a retrospectively evaluated case series, not a randomised trial, and the order of the two protocols was not randomly assigned. The authors state this limitation themselves. The magnitude of the difference in enzyme requirement nevertheless indicates the direction.
What this means in practice. Hyaluronidase does not distinguish between injected filler and the body's own hyaluronic acid. The less enzyme required and the more precisely it is placed, the less surrounding tissue is affected. Covered in detail on dissolving hyaluronic acid.
Approach to a nodule or swelling
The order in which I proceed
If an induration, a nodule or a swelling persists after a filler treatment, the decisive question is not whether something can be dissolved but what is sitting there. This sequence separates the cases.
Why this practice
First the finding, then the needle.
A hyaluronic acid deposit, a scar induration and an inflammatory nodule feel similar under the finger and call for opposite treatments. Whoever decides without an image decides on probability. On ultrasound, hyaluronic acid appears as a demarcated, hypoechoic structure; colour Doppler shows whether the surrounding tissue is hypervascularised, which points to an inflammatory process.
As a consultant anaesthesiologist, imaging structures beneath the skin is part of my clinical routine — it is the same technique I use to locate nerves for regional anaesthesia. I have completed courses in vascular and nerve sonography, abdominal sonography and focused emergency sonography. What had to be added for aesthetic work is the anatomy of the face as it appears on ultrasound.
- Clinical examination and history. When was the treatment, with what, how often, how has it changed. Redness, warmth, tenderness and the time course are the first points of triage.
- High-resolution ultrasound with colour Doppler. Position, depth, demarcation and vascularity of the change. At the same time the vessels in the area, should an injection follow.
- Classification of the finding. A demarcated hyaluronic acid deposit, scar or connective tissue induration, an inflammatory nodule — or a material that does not behave like hyaluronic acid on imaging and therefore probably is not one.
- Treatment according to the finding. For a non-inflammatory hyaluronic acid deposit, targeted low-dose dissolution under vision. An inflammatory nodule requires antibiotic treatment alongside. Where the finding remains unclear and a granuloma is suspected, referral for histological assessment — not repeated attempts at dissolution.
Limits
What imaging can do — and what it cannot
| Expectation | Realistic assessment |
|---|---|
| It shows the vessels before injection | Yes — course, depth and flow within the imaged section |
| It shows existing filler material | Usually yes; limited with very old or largely degraded deposits |
| It allows needle guidance under vision | Yes, with practice — the needle must be kept in the scan plane |
| It identifies material types reliably | Not always; the image supports a reasoned assignment, not proof of material |
| It rules out complications | No. No imaging method can do that |
| It replaces anatomical knowledge and experience | No — it adds the individual finding to both |
Frankly
No method makes a treatment risk-free
Injections in the face carry risks, even when performed carefully and even with imaging. Ultrasound improves planning and control — it is not a guarantee. Anyone promising you safety is promising too much. And: the benefit of the method rests largely on case series, expert recommendations and anatomical studies, not on large comparative trials with complication rates as an endpoint. That evidence gap belongs in an honest account.
The next step
Look first, then decide
In the consultation we clarify whether and how a treatment makes sense for you — and whether a sonographic assessment contributes anything in your case. Private practice in Herzogenaurach, twelve minutes by car from Erlangen.
Frequently asked
About ultrasound-guided injection
Does the ultrasound examination hurt?
No. A probe with contact gel is placed on the skin and moved. There is no appreciable pressure and no perceptible warmth; the examination is painless and involves no radiation. Depending on the area it takes five to ten minutes.
What frequency is your transducer?
It is a linear probe with a frequency range of 8 to 20 megahertz and a maximum penetration depth of 4 centimetres, with colour and power Doppler. The frequency actually used depends on the depth of the structure in question: superficial deposits are imaged at the upper end, deeper vessels at the lower. The 2025 international consensus names a linear probe of at least 15 megahertz as the minimum requirement and explicitly permits hand-held devices.
Is a 24 megahertz device better?
Not across the board. A higher frequency increases resolution and simultaneously reduces penetration depth. For very superficial questions within the dermis that is an advantage; for imaging deeper facial arteries and deep fat compartments it is a disadvantage. What matters is that the frequency range fits the question and that the examiner reads the image reliably.
Is ultrasound used for every treatment?
No. For treatments in areas with few vessels and for small volumes, imaging is not always required. I use it before injections in vessel-rich areas, when dissolving hyaluronic acid and for botulinum toxin type A in deep muscle groups. Whether it makes sense in your case is discussed beforehand.
Can filler be seen on ultrasound?
Yes. Hyaluronic acid appears on high-resolution ultrasound as a demarcated, hypoechoic area distinct from the surrounding tissue. Position, depth and approximate extent can be assessed. With very old or largely degraded deposits imaging can be more difficult. It is not proof of material in the sense of a laboratory analysis.
I no longer know what was injected. Does this still help?
Often yes. Different materials behave differently on ultrasound — in their demarcation, in the acoustic behaviour behind them and in the reaction of the surrounding tissue. That allows a reasoned assessment of whether hyaluronic acid is likely and whether an attempt at dissolution can make sense at all. Definitive identification of the material is not possible this way; where that question is decisive, it belongs in histological assessment.
Is this standard practice in aesthetic medicine?
Not yet across the board. In 2025 the international expert panel recommended by consensus that injections in many facial regions be performed under ultrasound guidance, and classified imaging in high vascular risk areas and in the management of complications as mandatory. In practice, adoption depends on whether suitable equipment is available and whether there is practice in using it.
Why can an anaesthesiologist do this?
Because ultrasound-guided puncture is part of specialist training in anaesthesiology — for central venous access and nerve blocks. I have completed courses in vascular and nerve sonography, abdominal sonography and focused emergency sonography. The skill of reading an ultrasound image and guiding a needle within it at the same time transfers. What had to be added is the anatomy of the face as it appears on ultrasound.
What does the examination cost in addition?
Medical services are billed under the German scale of fees for physicians (GOÄ). What applies to your treatment is discussed transparently in the consultation, before anything begins.
I was treated elsewhere and I am unsure — can I come?
Yes. Call the practice and we will clarify in advance what the matter is and whether a sonographic assessment helps in your case. The assessment is open-ended — which expressly includes the possibility that I advise against any treatment. I do not need to know who performed the original treatment.
Evidence base
What the studies show
- Velthuis PJ, Alfageme F, Cartier H et al., 2025. The use of ultrasound imaging in aesthetic injectables: A modified Delphi consensus. J Plast Reconstr Aesthet Surg 104:33–37. PMID 40101353. Four-round Delphi process with fifteen international experts from seven disciplines and eleven countries. The basis of the equipment section on this page: linear probe of at least 15 MHz for both learning and routine diagnostics, hand-held devices explicitly permitted, B-mode plus colour and spectral Doppler and image archiving mandatory, power Doppler recommended. Pre-injection imaging mandatory in areas at high vascular risk and in the management of complications; ultrasound-guided injection recommended in many facial regions and necessary for precise intralesional injections.
- Cotofana S, Velthuis PJ, Alfertshofer M et al., 2021. The Change of Plane of the Supratrochlear and Supraorbital Arteries in the Forehead — An Ultrasound-Based Investigation. Aesthet Surg J 41(11):NP1589–NP1598. PMID 33652475. Ultrasound-based measurement of the course of the forehead arteries. The spread of positions relative to the glabellar line, extending into negative values, is the evidence that anatomical means do not represent the individual case.
- Schelke LW, Velthuis PJ, Decates T et al., 2023. Ultrasound-Guided Targeted vs Regional Flooding: A Comparative Study for Improving the Clinical Outcome in Soft Tissue Filler Vascular Adverse Event Management. Aesthet Surg J 43(1):86–96. PMID 35951759. Retrospectively evaluated case series of 39 patients: a mean of 122.5 international units of hyaluronidase under ultrasound guidance versus 1,519 units with regional flooding. After flooding, 92.3% showed no improvement; after the subsequent ultrasound-guided protocol all patients improved immediately. Not a randomised design — the order of protocols was fixed, which limits the comparison.
- Schelke LW, Velthuis P, Kadouch J, Swift A, 2019. Early ultrasound for diagnosis and treatment of vascular adverse events with hyaluronic acid fillers. J Am Acad Dermatol 88(1):79–85. PMID 31325548. Duplex ultrasonography to locate the material causing arterial obstruction. Key statement: treated in time, a single ultrasound-guided enzyme injection into the deposit can prevent skin necrosis.
- Velthuis PJ, Jansen O, Schelke LW et al., 2021. A Guide to Doppler Ultrasound Analysis of the Face in Cosmetic Medicine. Part 1: Standard Positions. Aesthet Surg J 41(11):NP1621–NP1632. PMID 33954581. The system of seven standard probe positions from which the anatomical reference points of the face can be located — the methodological basis of a reproducible examination.
- Sigrist R, Desyatnikova S, Chammas MC, Vasconcelos-Berg R, 2024. Best Practices for the Use of High-Frequency Ultrasound to Guide Aesthetic Filler Injections — Part 1: Upper Third of the Face. Diagnostics 14(16):1718. PMID 39202206. Practical recommendations for the forehead and temple region.
- Schelke LW, Decates TS, Velthuis PJ, 2018. Ultrasound to improve the safety of hyaluronic acid filler treatments. J Cosmet Dermatol 17(6):1019–1024. PMID 30084182. Early work on imaging hyaluronic acid and mapping vessels before treatment.
References retrieved via PubMed. The works cited describe the state of the literature and do not support any claim about the outcome of an individual treatment.
Related
Further reading
- Dissolving hyaluronic acidHow the enzyme works, what dose makes sense and when dissolving is not the right answer.
- Hyaluronic acid fillersWhich regions are treated, which material behaves how, and where the limits lie.
- Diagnostic ultrasoundThe same technique outside aesthetic medicine — thyroid, abdomen, vessels.
- Cheek augmentationOne of the regions where vessel anatomy decides the approach.
Treating physician
Dr. med. Thomas Ackermann
Consultant Anaesthesiologist · Medical Director, Harmonie der Ästhetik
Safety is not a feeling that can be conveyed. It is something you show. That is why the screen faces you — and why I also tell you where this method reaches its limits.
Note. This page describes a way of working and does not replace the personal informed-consent consultation required under § 630e of the German Civil Code. Whether a treatment is appropriate for you, which method is used and which risks apply is determined exclusively in a personal appointment. Private billing under the German scale of fees for physicians (GOÄ).
This page offers a first overview. What a treatment means for you specifically — which method, which dosage, which expectation is reasonable — belongs in a personal conversation at the practice. Unhurried, with a finding, with time.
Harmonie der Ästhetik · Dr. med. Thomas Ackermann · Niederndorfer Hauptstraße 41 · 91074 Herzogenaurach · Phone +49 9132 90 24 770
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