Computer Aided Diagnosis

Computer-aided diagnosis (CAD) is one of the major research subjects in medical imaging and diagnostic radiology. CAD is a relatively young interdisciplinary technology combining elements of artificial intelligence and digital image processing with radiological image processing. A typical application is the detection of a tumor. For instance, some hospitals use CAD to support preventive medical check-ups in mammography (diagnosis of breast cancer), the detection of polyps in the colon, and lung cancer. Computer-aided detection (CADe) systems are usually confined to marking conspicuous structures and sections. Computer-aided diagnosis (CADx) systems evaluate the conspicuous structures. For example, in mammography CAD highlights micro calcification clusters and hyperdense structures in the soft tissue. This allows the radiologist to draw conclusions about the condition of the pathology. Another application is CADq, which quantifies, e.g., the size of a tumor in contrast medium uptake. Computer-aided simple triage (CAST) is another type of CAD, which performs a fully automatic initial interpretation and triage of studies into some meaningful categories (e.g. negative and positive). CAST is particularly applicable in emergency diagnostic imaging, where a prompt diagnosis of critical, life-threatening condition is required.

Molecular Breast Imaging

Molecular breast imaging also known as scintimammography is a type of breast imaging test that is used to detect cancer cells in the breasts of women who have had abnormal mammograms, or who have dense breast tissue or other type of suspicious lesions. MBI is not used for screening or in place of a mammogram. In this test, a woman receives an injection of a small amount of a radioactive substance called technetium 99 sestamibi, which is taken up by cancer cells, and a gamma camera is used to take pictures of the breasts.

Artificial Heart

A synthetic replacement for the heart remains one of the holy grails of modern medicine. Although the heart is conceptually simple it embodies subtleties that defy straightforward emulation with synthetic materials and power supplies. Consequences of these issues include severe foreign-body rejection and external batteries that limit patient mobility. These complications limited the lifespan of early human recipients to hours or days.

There are two types of artificial heart:
1. Total Artificial Heart (TAH) implantation involves the removal of the native heart. It is a surgical procedure similar to heart transplantation with a human donor heart.
2. Cardiac (heart) assist devices differ, in that the patient’s heart is not removed during implantation. Assist devices may include either a Left Ventricular Assist Device (LVAD) or a Right Ventricular Assist Device (RVAD) or both. As opposed to TAH implantation, the assist device serves to provide only a part of the total cardiac output of the patient’s heart.

Patients who have some remaining heart function but who can no longer live normally may be candidates for ventricular assist devices which do not replace the heart, but boost its output. The first heart assist device was FDA approved in 1994, and two more received approval in 1998. While the original assist devices emulated the pulsating heart newer versions, such as the Heartmate II, developed by the Texas Heart Institute of Houston, Texas, provide continuous flow. These pumps (which may be cetrifugal or axial flow) are smaller and potentially more durable and long-lasting than the current generation of total heart replacement pumps. Several continuous flow ventricular assist devices have been approved for use in the European Union and as at August 2007 were undergoing clinical trials for FDA approval.

Cardiac Pacemaker

The heart cells that create rhythmical impulses are called pacemaker cells, and they directly control the heart rate. Artificial devices also called pacemakers can be used after damage to the body's intrinsic conduction system to produce these impulses synthetically.
Although all of the heart's cells possess the ability to generate these electrical impulses (or action potentials), a specialised portion of the heart, called the sinoatrial node, is responsible for the whole heart's beat.
The sinoatrial node (SA node) is a group of cells positioned on the wall of the right atrium, near the entrance of the superior vena cava. These cells are modified cardiac myocytes. They possess some contractile filaments, though they do not contract.

Cells in the SA node will naturally discharge (create action potentials) at about 70-80 times/minute. Because the sinoatrial node is responsible for the rest of the heart's electrical activity, it is sometimes called the primary pacemaker.

If the S.A node doesn't function, or the impulse generated in the SA node is blocked before it travels down the electrical conduction system, a group of cells further down the heart will become the heart's pacemaker. These cells form the atrioventricular node (AV node), which is an area between the atria and ventricles, within the atrial septum.

The cells of the AV node normally discharge at about 40-60 beats per minute, and are called the secondary pacemaker.
Further down the electrical conducting system of the heart, the Bundle of His, the left and right branches of this bundle, and the Purkinje fibres, will also produce a spontaneous action potential if they aren't inhibited by other electrical activity. These tertiary pacemakers fire at a rate between 30-40 per minute.
Even individual cardiac muscle cells will contract rhythmically on their own.
The reason the SA node controls the whole heart is that its action potentials are released most often; this triggers other cells to generate their own action potentials. In the muscle cells, this will produce contraction. The action potential generated by the SA node, passes down the cardiac conduction system, and arrives before the other cells have had a chance to generate their own spontaneous action potential.

Acetylsalicylic Acid

Aspirin or acetylsalicylic acid is a drug in the family of salicylates, often used as an analgesic (against minor pains and aches), antipyretic (against fever), and anti-inflammatory. It has also an anticoagulant (blood thinning) effect and is used in long-term low-doses to prevent heart attacks.

The brand name Aspirin was coined by the Bayer company of Germany. In some countries the name is used as a generic term for the drug rather than the manufacturer's trademark. In countries in which Aspirin remains a trademark, the initialism ASA is used as a generic term (ASS in German language countries, for Acetylsalicylsäure).

Because there appears to be a connection between aspirin and Reye's syndrome, aspirin is no longer used to control flu-like symptoms in children.

Low-dose long-term aspirin irreversibly blocks formation of thromboxane A2 in platelets, producing an inhibitory affect on platelet aggregation, and this blood thinning property makes it useful for reducing the incidence of heart attacks. Aspirin produced for this purpose often comes in 75 or 81 mg dispersible tablets. High doses of aspirin are also given immediately after an acute heart attack.

Several hundred fatal overdoses of aspirin occur annually, but the vast majority of its use is beneficial. Its primary undesirable side effects, especially in stronger doses, are gastrointestinal distress (including ulcers and stomach bleeding) and tinnitus. Another side effect, due to its anticoagulant properties, is increased bleeding in menstruating women. Aspirin was the first discovered member of the class of drugs known as non-steroidal anti-inflammatory drugs (NSAIDs), not all of which are salicylates, though they all have similar effects and a similar action mechanism.