Task 4 - Creation Diagnostic Techniques of Breast AC.

 

Task 4 - Creation Diagnostic Techniques of Breast AC 

Breast cancer can be diagnosed using a variety of diagnostic techniques, both imaging and laboratory. These techniques are critical for determining the presence of breast cancer, assessing its extent, and guiding appropriate atment.

Mammography

Definition

It is a medical imaging technique used to detect and diagnose breast diseases, by using ionizing radiation to create detailed images of breast structures. It is mainly used to detect early signs of breast cancer, such as masses, microcalcifications, and other abnormal changes in breast tissue.

Physical Radio Principle 

Mammography uses low-energy x-rays that pass through the breast tissue. The differential absorption of X-rays by different structures within the breast allows the formation of a radiographic image. Dense tissues, such as tumor masses, microcalcifications, and glandular fibers, appear differently on mammographic imaging due to their different densities.

Indications of the exam

- Routine screening for early detection of breast cancer in women over 40 years of age.

- Evaluation of symptoms such as lumps, skin changes, or abnormal breast discharge.

- Follow-up of patients with a family history of breast cancer or other breast conditions.

How Images Are Taken

During a mammogram, the patient is positioned in front of the mammogram machine and the specialized technician places the breast between two compression plates. Compression is necessary to disperse breast tissue and obtain high-quality images with lower radiation doses. Multiple images are taken at different angles and positions for a complete evaluation of the breast tissue. 

Radiation Dose (kV and mAs)

The radiation dose in a mammogram varies depending on the technique used, but usually involves a low level of radiation.

- MLO: 25-30 kV, 100-200 mAs 

- DC: 25-30 kV, 100-200 mAs 

Basic Projections

 - Oblique Mediolateral Projection (MLO): This is the standard and most common projection. The patient stands in front of the mammogram machine and the breast is compressed between two plates. The x-ray beam is directed diagonally through the breast tissue from the side toward the center of the breast.

Craniocaudal (CC) Projection

In this projection, the breast is compressed vertically between the plates and an image is taken from top to bottom. This projection provides a more direct view of the breast tissue. 

Additional Screenings -Axillary Projection

To visualize the axillary region and detect nearby lymph nodes. - Medial-Lateral Compression Projection (MLO-C): Similar to MLO but with additional compression to better displace tissue. - Lateral Projection: To visualize the lateral breast tissue.

Mammography sensitivity

Sensitivity varies depending on several factors, including the age of the patient, the density of the breast tissue, and the experience of the radiologist. In general: 

- The sensitivity of mammography in asymptomatic (asymptomatic) women is approximately 85% to 90%. This means that mammography can detect about 85% to 90% of breast cancers in women who have no symptoms.

- Sensitivity may be lower in younger women or those with dense breast tissue, as breast density can hide small lesions

Specificity of Mammography

The specificity of mammography is usually high, especially when combined with additional evaluations such as breast ultrasound or MRI. - The specificity of mammography may be affected by the presence of benign imaging abnormalities, which can lead to false positives (i.e., abnormal results that are not cancer). - In general, mammogram specificity is around 90% or higher, which means that most negative results are truly negative for breast cancer.

According to the American College of Radiology (ACR), breasts are classified as

A = the breasts are almost entirely fat 

B = there are several scattered areas of fibroglandular tissue

C = the breasts are heterogeneously dense, which can hide small masses 

D = the breasts are extremely dense, which decreases the sensitivity of the mammogram

Ultrasound. 

Definition: Breast ultrasound is an imaging technology that uses high frequencies of ultrasound that cannot be detected by the human ear. The reflection of these sound waves from various tissue structures is converted into images that radiologists can interpret. In general, breast ultrasound gives very good images.

Contraindications

Diagnostic ultrasound has no risks or contraindications and can be performed as many times as necessary. 

How it's done. 

The test is not uncomfortable or risky for the patient. During the ultrasound examination, the radiologist spreads an aqueous gel over both breasts that facilitates better contact and conduction of the transducer through the skin, improving the imagen.

The test usually doesn't take too long, usually no more than 15-30 minutes. 

https://images.app.goo.gl/NKhTYztckFdmimop8

Preparation. 

The only preparation that the patient needs is to discover the area of the body that is going to be explored, in this case the breasts, and to be calmly and relaxed lying on the table. 

https://images.app.goo.gl/ZBDxEGFNQmtWWikP9

RADIOPHYSICAL PRINCIPLES:

The frequency of sound is measured in number of cycles per unit of time. Normally, the second is used as a unit of time. The unit of frequency (cycles/sec) is called Hertz (Hz), 1 cycle/sec = 1 Hz, being a KiloHertz: 1,000 cycles/sec = 1,000 Hz = 1 KHz and a MegaHertz: 1,000,000 cycles/sec. = 1,000,000 Hz = 1 MHz. The higher the frequency, the higher the image quality, but the lower the penetration into the body1,3.

Sound

It is the result of the trajectory of energy through matter in the form of a wave that alternately produces the phenomena of compression and rarefaction.

Echoes

They are sounds, sound waves, that are reflected, bounced, after colliding with a surface or barrier captable of reflecting them. 

• The reflective interface is the surface or barrier capable of reflecting sounds, and therefore also ultrasound.
• This barrier or interface exists between two contiguous or adjacent media with different acoustic impedance.Acoustic impedance is the resistance that a medium opposes to the passage of ultrasound.
•   The acoustic impedance (Z) is the product of the density (D) of the medium times the speed (V) at which the ultrasound passes through it.

https://images.app.goo.gl/6bvA1f9iXnvnUZ6z9

GAMMAGRAFÍA

A scan is a nuclear medicine diagnostic test that uses gamma rays emitted by radioactive isotopes to create images of organs and tissues inside the body

Types of Scan

Static acquisition: consists of obtaining a single image for a certain period of time. The sum of static images around the patient is known as SPECT and is acquired together with computed tomography (CT) to obtain SPECT/CT images.

Dynamic acquisition: This consists of obtaining several images at different times during a given time interval.

Breast scan

Molecular breast imaging (MBI), also known as a scan, is a type of breast imaging test used to detect cancer cells in the breast tissue of people who have had abnormal mammograms, especially for those who have dense, postoperative breast tissue. Tissue or breast implants.

DIRECTIONS 

• Dense breast tissue. 
• Distortion of breast architecture. (from previous biopsies).
• Breast implants or prostheses. Palpable mass in one or both breasts with normal or doubtful mammography, or positive breast ultrasound and negative mammography. (low or intermediate malignancy) 
• Discover multifocal breast disease.

• Evaluation of response to chemotherapy (adjuvant).
• It is used when detection of breast abnormalities is not possible or reliable based solely on mammography and ultrasound. 
• Use in patients with contraindications (e.g., certain implantable devices) or who prefer to avoid MRI (claustrophobia, discomfort). 

COUNTER-INDICATIONS

It is contraindicated in pregnant women and nursing mothers

Team 

Breast-specific gamma cameras have been developed with a smaller field of view than conventional cameras, allowing for higher resolution imaging and compression of the breast as in x-ray mammography (improving detection of smaller lesions). 

A patient can expect to receive an injection of an intravenous radiopharmaceutical agent into the arm contralateral to the investigational breast. After waiting for 5 to 10 minutes, the breast tissue is placed into the MBI system and a series of images are obtained. The imaging time for both breasts is approximately 40 minutes.

Physical Radio Principle

Scintigraphy is based on the principle of scintigraphy, in which the gamma radiation emitted by injected radiopharmaceuticals is measured by gamma cameras. Cancer cells absorb radiopharmaceuticals at a higher rate than surrounding normal tissue and, as such, appear on scintigraphy as areas of increased gamma radiation emission

Radiopharmaceutical most commonly used in scintigraphy

most commonly used in scintigraphy: the most commonly used radiopharmaceutical in (MBI) is 99m tc-sestamibi, with doses of 240-300 MBq in current protocols, resulting in an effective dose for a patient of around 2.4 mSV

proyecciones

Caudal skull (left) and lateral middle oblique (right) Anteroposterior

BEAST MRI

RI is a test used to detect breast cancer or abnormalities. MRI takes pictures from many angles, MRIs use strong magnets instead of radiation to produce highly detailed cross-sectional images of the body, This MRI machine has a device called a dedicated breast coil to reproduce the image of the breast. It uses strong magnets, radio waves, and a computer to create pictures to show the extent of the cancer or a problem with the other breast and can be used along with a mammogram as an screening tool

Indications for Breast Magnetic Resonance Imaging

• Possible rupture or leakage in a breast implant 

• A high risk of breast cancer. This means a lifetime risk of 20% or more 

• Significant family history of breast cancer or ovarian cancer 

• Very dense breast tissues and mammograms that did not detect previous breast cancer 

• Breast changes such as atypical hyperplasia, carcinoma in situ 

• History of radiation treatments to the chest area between the ages of 10 and 30

Positioning of the Pact The patient

will be positioned in the prone position, with the arms positioned along the body to increase the anatomical coverage of the coil and help minimize the effects of breathing movement. The breasts are left hanging freely in the fullest and deepest way within the two openings of the respective coil holder, with the nipple pointing downwards. The anatomical coverage in the direction of the cut thickness should include from the supraclavicular region to the inframammary fold. The study should include both breasts.

TEAM 

-Coils: Breast coils are composed of matrices with a geometric design that provides high signal-noise (SNR), over the area that covers the two breasts, with an extension beyond the chest wall and axillary regions. The development of phase-array coils provides the acquisition of better images based on signal-to-noise optimization 

-Resonator: Several breast MRI protocols can be used to obtain quality images, current recommendations by standard accept images of 1.5 T or larger, since the greater field strength allows the acquisition of high resolution images, with an adequate SNR ratio and allows the use of fat suppression. 3.0 T resonator imaging provides a greater opportunity for improved SNR, increased image resolution, and faster acquisition

Imaging: FOV is used for unilateral breast imaging of 16-20 cm, while for bilateral images the field of view increases to 30-35 cm, with a matrix of 512 x 256 (depending on the sequence and cutting plane).

Magnetic Resonance Guided Biopsy: In this case of MRI-guided percutaneous biopsy, vacuum-assisted devices have several advantages over automatic core needles, since they are faster in terms of tissue collection and obtain a greater volume of tissue.

SEQUENCES 

 -T1 with contrast: all protocols have in common the assessment of lesions in the T1 GRE 3D sequence (20/4.5; tilt angle, 30º-45°, slice thickness ≤ 3 mm), with acquisitions before and after intravenous administration of contrast material, with the usual dose of 0.1 mmol/kg

-T2: boosted in T2 (Fast or Turbo) Spin Echo: It is the MS/ms repetition time echo time 4 000/90, cutting thickness 3 mm. It is used to characterize the breasts and any type of lesion 

-STIR: (Short I Inversion Recovery) is an alternative to T2 FSE sequences, when you want to suppress the fat signal and it does not have the field homogeneity requirements necessary for T2 sequences with fat suppression.

-MIPs: (maximum projection intensity) are normally generated to demonstrate the distribution and enhancement patterns

-Spectroscopy: The chemical composition of a lesion can be assessed with spectroscopy (MRD), which provides biochemical information about the tissue being assessed. The value is based on the detection of elevated levels of choline derivatives, collectively called (TCho), a tumor marker whose presence and increase in the concentration of the metabolite occurs in breast cancer and behaves as an upward chemical shift with a percentage change of (3.2 ppm particles per million). Recording Graphically

BIBLIOGRAFIA.

https://www.breastcancer.org/es/pruebas-deteccion/deteccion-molecular-mamaria-imagenes