Materials.
Phantom features.
The invention relates to the field of ultrasonic research.
Phantoms for assessing the echo-semiotics of foreign bodies of organic and inorganic origin consist of two bodies and parts.
The bodies of the phantom are made of silicone-containing material and have the form of a rectangular parallelepiped measuring 210x50x100 mm with foreign bodies arranged in pairs in two parallel rows at a depth of 5 mm and 20 mm.
The material from which the phantom was made has acoustic properties similar to the soft tissues of a person with a hypersthenic type of build (~ 1450 m/s).
The material is durable,
because it doesn't contain gelatin,
glycerine and other materials used in the creation of ultrasound phantoms of short duration.
The first phantom (inorganic foreign bodies) includes the following foreign bodies (Fig.
1):
1.
The glass (n = 2);
2.
The fragments of plastic (n = 2);
3.
The drainage tubes (n = 2);
4.
The dental screws (n = 2);
5.
The filling material (n = 2).
The second phantom (organic foreign bodies) includes the following foreign bodies (Fig.
2):
1.
The sunflower seeds (n = 2);
2.
The thorns of the roses (n = 2);
3.
The grass (n = 2);
4.
Wood (toothpicks) (n = 2);
5.
Helminths (n = 2).
Methods
In the clinical part of the experiment 12 patients with foreign bodies into the soft tissues of the maxillofacial region were examined.
In the experimental part both phantoms were examined with ultrasonography and computed tomography.
Ultrasound examination was performed using a linear transducer,
with a range of operating frequency of 7-15 MHz and a linear intraoperative transducer with a frequency of 5-17 MHz in B-mode (Fig.
3,
4).
A special gel pillow was used for ultrasound examination to improve the visualization (Fig.
5).
Then,
a computed tomography was performed for both phantoms by a 64-slice tomograph with the evaluation of the obtained images in the axial plane,
using multiplanar reconstructions (MPR),
MIP and 3D reconstructions (Fig.
6,
7).