Advanced Sonography of Near Field: Skin and Subcutaneous Structures - SD

Advanced Sonography of Near Field, Skin and Subcutaneous Structures

I am Dr. Leandro Fernandez, director of the Laboratory of Advanced Sonography at Institute Medical Florisa in Caracas, Venezuela.

It will be my pleasure to discuss the topic, advanced sonography of near field, skin and subcutaneous structures.

Let's begin sonography of near field, skin and subcutaneous structures.

To perform near field ultrasound is necessary to have transducers of high and very high frequency, high 10 or more megahertz and very high frequency, 20 of more megahertz.

With this technology, we can make a proper assessment of superficial structures.

There are many applications, many clinical applications in different medical specialties have radiology, traumatology, rheumatology, dermatology, and this is an example.

This is an image correspondent to an ocular melanoma. This is B mode, and here is a very vascularized lesion. And here we have the three dimensional reconstruction of this tiny lesion located at the posterior pole of the eye.

Advanced Techniques

We use the expression advanced sonography, and this is a group of techniques, of techniques where we can include doppler in all its modalities. Three dimensional ultrasound contrast agents, harmonic imaging, real time compound ultrasound, extended field of view, ultrasound, and many new technological advances.

Equipment Recommendations

The equipment recommended to perform this kind of ultrasound is a digital system with ultra-high resolution 0.1 millimeter or higher, depending on the frequency of the transducers.

Normally in clinical practice, in radiological centers, we use 13 to five megahertz, or 17 to five megahertz.

There are special transducers only dedicated, not for general ultrasound, but just for dermatological applications with 35, 45 or more megahertz.

In this lecture, we are referring to the equipment that we can have in radiological labs or vascular labs.

Imaging of Skin and Subcutaneous Structures

This image correspond to a very superficial structure in this case of the skin, but also subcutaneous aponeurosis and muscle.

This hyper cogenic band correspond to the dermis. Subcutaneous is hyper cogenic. Then we have a hyper genic line, the upper aponeurosis, and here are the hyper echogenic image corresponding to the muscle.

This image was taken with 12 megahertz.

With 17 megahertz transducer, we can obtain a better definition of the same structures. Again, here we have the very superficial area of the dermis. We can also see some areas of the epidermis here. We can observe the basal, and subcutaneous again, aponeurosis and muscular field.

It's important to have the proper frequency to make these applications or to use these applications, skin and subcutaneous.

We can observe dermatological diseases, focal or diffused ones. We can observe vessels, very superficial vessels, muscles, lymph nodes for bodies. And this technique can be also used for fine needle aspiration guided samples by ultrasound.

Clinical Examples

Let's see some clinical examples of the applications of the near field ultrasound.

These hyper echogenic image here correspond to a breast metastases in the skin. We are working here with 12 megahertz, and we are using gel as an acoustic window or as an acoustic pathway.

This is the three dimensional reconstruction of the same structure. By using this technology, we can offer a 3D rendering, and we can observe how the lesion penetrates to the superficial areas and penetrates to the internal planes.

Also, in this case, the invasion takes the aponeurosis not only in the subcutaneous area, but also the aponeurosis going to the muscle.

These lesions are vascularized, and the doppler can offer depiction of these vessels.

This is the picture or the photography of the ocular melanoma. And here we can observe by using 17 megahertz, the extension of the lesion and how the lesion penetrates to the deeper planes of the skin.

Now we have a closeup. We're zooming in, and here we can observe how the lesion is vascularized. We can help to the differential diagnosis by using this technology.

This is a very suspicious lesion here, but it is not vascularized. Of course, we don't intend to make a substitution of the biopsy. We just want to offer more information to the clinician, to the dermatologist in order to take the decisions of how the patient, this patient must be studied.

Here we have an example of a patient with psoriatic. We see here an enlarged dermis, and we can compare the same patient in a normal area. And here we are making the ultrasound in an affected area. And here we can see how evident is the difference of the thickness of the skin in this case. And we can use this method to compare the results previous to treatment.

So this is one application in dermatological patients, just to remain the fingertip anatomy. Here we have the germinal matrix of the nail. This is the nail body we have here, the distal bone. And this structure here correspond just to the fingertip.

Let's see, how can we observe the fingertip by using ultrasound? And here we have the bone. We have, again, the nail, the structure of the nail. This is the matrix here, and this is the proper fingertip. And this is the three dimensional reconstruction.

We have a picture here to just to be oriented. And here we can observe even the superficial changes of the nail. And here we can also see the fingerprints.

Let's rotate this image by using the three-dimensional technology. And we have a lesion in this area. Here we have an hyper echogenic lesion. This patient have a very specific clinical manifestation, a very intense pain to the touch of the fingertip.

This is characteristic of a condition called glomus tumor. A glomus tumor is a vascular tumor that usually can be found in the fingertips, sometimes in the knees, sometimes in different parts of the body, but it's very frequent to find these lesions just in the fingertips.

There are vascularized lesions, and we are demonstrating here the presence of vessels by using the color doppler.

This is an intramuscular tumor. Now we have the three dimensional reconstruction, longitudinal, and coronal plane. And here we are using a new technique of three dimensional ultrasound, depending of the company that you are working with. The it has different names, 3D slices, I slices, but it's some kind. And somehow it's a multi slice presentation of a three dimensional image, very related with the MRI or helical CT scan.

With this technique, we can observe a very detailed depiction of the borders and the extension of the lesion. And similar to MRI or CT scan, we have these lines here, and we can program the computer in order to show us the image corresponding to each determined line. We can change the color in order to have a better observation for the human eye.

Now we have another example here. This is a fistula of the wrist after a surgical procedure, superficial, very superficial echo here, and we can observe how the lesion penetrates. Really, it's not penetrating really, it's rising from the deeper planes to the superficial ones.

This is a rare condition. This is intramuscular abscess, but taking all the muscle, external clay mastoid muscle. This is a tropical myositis by using here extended field of view ultrasound.

We have the submandibular angle here, and we have the clavicular bone here. This is an extended image of 15 centimeters, and we have an altered echogenicity inside the muscle with loss of the normal architecture of this structure.

And here another view by using the zoom of this same example and here the three dimensional reconstruction where we can observe the superficial structure here. This is the muscle and this is the affected area.

This is a case of a diabetic patient with a plantar abscess. We're using here again, extended field of view ultrasound. Those are the toes here. The this is the bone component, and this is the subcutaneous and muscle here. So is an extensive lesion here, taking all the plantar region. And this is prudent content.

Another example of the sternocleidomastoid muscle, but this is a localized abscess. And here we are placing a needle. This is the tip of the needle. And here our intention was to take a sample for bacteriological purposes.

Three dimensional ultrasound can be also used to guide punctures. And in this case, we are observing here again, the needle. This is the needle tip. And in three planes, we are absolutely sure that we are located inside the lesion because we have the longitudinal, the transversal, and the coronal view at the same time, on the same screen.

One of the advantages of the three-dimensional ultrasound, this case corresponds to a hemangioma, a very vascularized and superficial lesion here with power doppler. And here it was a 17 day newborn. And here we have the lesion in B mode. This is the spine here, and this is the superficial planes. And here I showed you before the color doppler.

Sometimes ultrasound can be very useful, more useful than others imaging techniques. In this case, we have this lesion here. Another aspect or another perspective here, we have the MRI of this lesion And compare the information provided by the MRI and the information provided by high resolution and high frequency ultrasound.

In this case, we worked with 17 megahertz, so we can determine the extension of the lesion. This is normal area, but here we have altered echogenicity. Here we have the concentration of the lesion. And here we can observe a bad defined, poor defined limits.

This lesion is a lymphatic malformation, and the diagnostic is done with the help of doppler. This is an aspect, and here we have no vascularization detected by using the color doppler.

This is the difference between the hemangioma and the lymphatic non vascularized lesions.

This is the image of a gang cyst non vascularized. Again, in this case here we have a tendonitis and synovitis of a finger. This patient had an operation here, and this is a complication of the operation. And we can observe here the two tendons. This is the bone and very superficial structure here. And this is the three dimensional reconstruction where we can observe the two tendons here. The two portion of the tendon, of course, surrounded by the collection, corresponded to the lesion.

Another example using extended field of view ultrasound. This patient have a traumatism. This lesion is in the thigh, and here we can observe the bone and we can observe here the hematoma, a big hematoma and another collection beside we have here zoom. And we have the extended field here surrounding the gulf.

Another example, this is a venous thrombosis taking the jugular vein with extended field of ultrasound. This is the vessel, and those echoes here correspond to the thrombosis.

Cervical cystic hygroma. It's a complex image with hypoechoic portions with septa. And here the color Doppler help us to make the differentiation between hemangioma and hygroma again, no color flow detected, but here is the same lesion by using the extended field of view ultrasound.

This is another cystic hygroma, but a non cervical case. This lesion is located in the back of the patient, in the dorsal area of the patient. This is the spine here, and this is the paravertebral muscles and very superficial lesion here. And now we are observing a closeup by using the zoom tool. And again, no color doppler detected.

This is an interesting case. This patient step on something that he couldn't define. And then he came to our lab referred by the specialist. And we found this image here in transversal view, this image here with acoustic shadow and here in longitudinal. So it correspond to a foreign body that was extracted by surgical treatment.

Superficial lymph nodes can also observed by using near field ultrasound. And here this is a benign lesion, hyper vascularized, but well-defined. And this is a malignant lymph node. Very bad defined here, very irregular and with vascularization, but with very altered vascularization.

Superficial vessels can also be observed by using this technique. Here we can observe the gastrocnemius vein, and we can observe here very superficial varices with three dimensional ultrasound, we can make reconstruction of venous thrombosis. And this is the case that we are observing the thrombus in a very superficial vein.

Lymphedema can also be assessed with superficial ultrasound and different grades of lymphedema can be determined.

An example of a normal cartilage of the nose. And here we have a malignant lesion. This is a basal cell carcinoma, and we can see the penetration of the lesion. This is the normal skin. This is the normal cartilage. And here we can observe the lesion and the penetration in deeper planes and disease. The cartilage that we can observe the same normal structure as seen in the previous or on the opposite side.

In this case, we have a vascular malformation of lip. This area hyper vascularized with these gin nose vessels better depicted by using power doppler. And here we have the three dimensional reconstruction of this area. This is a vascular malformation of lip.

Conclusions

So in conclusions, skin ultrasound, near field ultrasound, it's a harmless study, painless that can be done with portable system if we have the proper frequency, if we have the transducer with the proper frequency and this study offered anatomic information and three dimensional reconstruction. Provides a very effective view of this small structure as we demonstrate here in our previous images, advanced sonography of near field skin and subcutaneous structures.