Radiological Health Program
Vascular sonography has become the imaging modality of choice for evaluating veins for thrombosis, carotid arteries for plaque build up, and arteries for aneurysms or dissection. Color and Spectral Doppler sonography are required part of each vascular sonogram.
The diagnostic information obtained from a Vascular sonogram includes both structural and functional Information of a blood vessel. The combination of information gives it a distinct advantage over other imaging modalities.
Cardiovascular disease accounted for 1.6 million deaths in the region of the Americas in 2012, with hypertension identified as the main risk factor. Complications of long term uncontrolled hypertension include arteriosclerosis, heart failure, stroke, aneurysm including dissection of the aorta.
Cervical cancer in low income countries continues to grow even as rates fall in high-income countries. Greater than 80% of cervical cancer cases occur in low and middle income countries. This disparity is primarily due to limited access of prevention, screening and treatment services in low resource countries.
Although Papanicolaou test (PAP smear) tests are the preferred screening tool, sonography can be used to assess the uterus, ovaries, and adnexa for any changes that would suggest abnormalities and disease. An ultrasound exam evaluates external aspects of the uterus and cervix such as the contour and size, and the internal surfaces such as the endometrial and endocervical lining for abnormal thickness.
Cervical cancer leads to changes to the size and normal sonographic pattern of the cervix. Utilizing color Doppler imaging can add specificity to cancer diagnosis by demonstrating increased blood flow commonly found with tumor invasion and infiltration.
Diabetes is a chronic disease that has been steadily increasing worldwide. Poorly controlled diabetes impacts every organ system in the human body and increases the chance of premature mortality. Chronic complications for diabetes include cardiovascular disease, blindness and renal failure
Sonography can be used to evaluate the overall size of the kidneys, thickness and appearance of the renal cortex, and the blood vessels that supply each kidney all of which can be impacted as a result of Chronic Renal Failure
The most common indication for an ultrasound exam of the spleen is to evaluate the overall size of the organ for splenomegaly. The spleen has multiple functions that include filtering of blood and fighting infections as part of the immune system.
Sonographic evaluation of the spleen includes assessment of size and the gray scale appearance of the parenchyma. Splenomegaly is a common clinical finding, although nonspecific, for many of the Neglected Tropical Diseases (NTD). Infections and abscess formation within the spleen can alter the gray scale appearance of the parenchyma.
Visceral Leishmaniasis is one of the NTD that is associated with splenomegaly; if left untreated 90% of patients die.
Ultrasound evaluation of the liver utilizes normal sonographic appearance of the parenchyma as the baseline to determine presence of disease.
Liver sonograms assess the overall size, border contour, gray scale appearance of the parenchyma including the bile ducts and blood vessels within the organ. Acute and chronic liver disease can be identified by changes to the sonographic appearance of these assessed areas of the liver.
Identification and monitoring of Hepatocellular diseases such as Hepatitis and Cirrhosis can be accomplished with sonography. It is estimated that in Latin America and the Caribbean 2.1 million people are Infected with Hepatitis B and 4.1 million are infected with Hepatitis C.
Chronic Hepatitis and Cirrhosis lead to a decrease in the overall size of the liver, the borders become lobulated rather than smooth, the hepaticytes becomes fibrotic which changes the gray scale appearance of the parenchyma, and the blood flow to and within the liver can reverse direction.
Additional ResourcesPAHO Web. Hepatitis