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Fibroadenomas (fy-broe-ad-uh-NO-muhz) are solid, noncancerous breast tumors that occur most often in adolescent girls and women under the age of 30. You might describe a fibroadenoma as firm, smooth, rubbery or hard with a well-defined shape. Usually painless, a fibroadenoma might feel like a marble in your breast, moving easily under your skin when touched. Fibroadenomas vary in size, and they can get bigger or even shrink on their own. Fibroadenomas are among the most common breast lumps in young women. Treatment may include monitoring to detect changes in the size or feel of the fibroadenoma, a biopsy to evaluate the lump, or surgery to remove it.
An omentectomy is a surgical procedure designed to remove the omentum, which is a thin fold of abdominal tissue that encases the stomach, large intestine and other abdominal organs. This fatty lining contains lymph nodes, lymph vessels, nerves and blood vessels.
The complex circuitry interconnecting different areas in the brain, known collectively as white matter, is composed of millions of axons organized into fascicles and bundles. Upon macroscopic examination of sections of the brain, it is difficult to discern the orientation of the fibers. The same is true for conventional imaging modalities. However, recent advancements in magnetic resonance imaging (MRI) make such task possible in a live subject. By sensitizing an otherwise typical MRI sequence to the diffusion of water molecules it is possible to measure their diffusion coefficient in a given direction1. Normally, the axonal membrane and myelin sheaths pose barriers to the movement of water molecules and, thus, they diffuse preferentially along the axon2. Therefore, the direction of white matter bundles can be elucidated by determining the principal diffusivity of water. The three-dimensional representation of the diffusion coefficient can be given by a tensor and its mathematical decomposition provides the direction of the tracts3; this MRI technique is known as diffusion tensor imaging (DTI). By connecting the information acquired with DTI, three-dimensional depictions of white matter fascicles are obtained4. The virtual dissection of white matter bundles is rapidly becoming a valuable tool in clinical research.
Our journey begins with a transverse section of tightly packed axons as seen through light microscopy. Although represented as a two-dimensional "slice", we see that these axons in fact resemble tubes. A simulation of water molecules diffusing randomly inside the axons demonstrates how the membranes and myelin hinder their movement across them and shows the preferred diffusion direction --along the axons. The tracts depicted through DTI slowly blend in and we ride along with them. As we zoom out even more, we realize that it is a portion of the corpus callosum connecting the two sides of the brain we were traveling on and the great difference in relative scale of the individual axons becomes evident. The surface of the brain is then shown, as well as the rest of the white matter bundles--a big, apparently chaotic tangle of wires. Finally, the skin covers the brain.
With the exception of the simulated water molecules, all the data presented in the animation is obtained through microscopy and MRI. Computer algorithms for the extraction of the cerebral structures and a custom-built graphics engine make our journey through the brain's anatomy possible in a living person.
Micrograph courtesy of Dr. Christian Beaulieu, University of Alberta.
Music by Mario Mattioli.
References:
1. Stejskal, E.O., et al., J. Chem. Phys., 1965. 42:
2. Beaulieu, C., NMR Biomed., 2002. 15:435-55.
3. Basser, P.J., et al., J. Magn. Reson. B, 1994. 103:247-54.
4. Mori, S., et al., NMR Biomed., 2002. 15:468-80.
Digoxin is used to treat heart failure, usually along with other medications. It is also used to treat a certain type of irregular heartbeat (chronic atrial fibrillation). Treating heart failure may help maintain your ability to walk and exercise and may improve the strength of your heart. Treating an irregular heartbeat can decrease the risk for blood clots, an effect that may reduce your risk for a heart attack or stroke.
Constipation is a common problem. It means either going to the toilet less often than usual to empty the bowels, or passing hard or painful stools (faeces). Constipation may be caused by not eating enough fibre, or not drinking enough fluids. It can also be a side-effect of certain medicines, or related to an underlying medical condition. In many cases, the cause is not clear. Laxatives are a group of medicines that can treat constipation. Ideally, laxatives should only be used for short periods of time until symptoms ease. Note: there is a separate leaflet on constipation in children. What is constipation? Constipation is common. If you are constipated it causes one or more of the following: Stools (faeces) become hard and difficult or painful to pass. The time between toilet trips increases compared with your usual pattern. (Note: there is a large range of normal bowel habit. Some people normally go to the toilet to pass stools 2-3 times per day. For others, 2-3 times per week is normal. It is a change from your usual pattern that may mean that you are constipated.) Sometimes, crampy pains occur in the lower part of your tummy (abdomen) You may also feel bloated and feel sick if you have severe constipation. What are the causes of constipation? Known causes include the following: Not eating enough fibre (roughage) is a common cause. The average person in the UK eats about 12 g of fibre each day. But, 18 g per day is recommended by the British Nutrition Foundation. Fibre is the part of plant food that is not digested. It remains in your gut. It adds bulk to the stools (faeces) and helps your bowels to work well. Foods high in fibre include fruit, vegetables, cereals and wholemeal bread. Not drinking much may make constipation worse. Stools are usually soft and easily passed if you eat enough fibre and drink enough fluid. However, some people need more fibre and/or fluid than others in order to avoid constipation. Some special slimming diets are low in fibre and may cause constipation. Some medicines can cause constipation as a side-effect. Examples are painkillers (particularly those with codeine, such as co-codamol, or very strong painkillers, such as morphine), some antacids, some antidepressants (including amitriptyline) and iron tablets; however, there are many others. See the list of possible side-effects on the leaflet that comes with any medicine that you may be taking. Tell a doctor if you suspect a medicine is making you constipated. A change of medication may be possible. Various medical conditions can cause constipation. For example, an underactive thyroid gland, irritable bowel syndrome, some gut disorders and conditions that cause poor mobility, particularly in the elderly. Pregnancy. About 1 in 5 pregnant women will become constipated. It is due to the hormonal changes of pregnancy that slow down the gut movements. In later pregnancy, it can simply be due to the baby taking up a lot of room in the tummy and the bowels being pushed to one side.
Epidermoid cysts, also called sebaceous, keratin, or epithelial cysts, are small, hard lumps that develop under the skin. These cysts are common. They grow slowly. They do not cause other symptoms and are nearly never cancerous. Epidermoid cysts are often found on the face, head, neck, back, or genitals
Pneumonia is an infection that inflames the air sacs in one or both lungs. The air sacs may fill with fluid or pus (purulent material), causing cough with phlegm or pus, fever, chills, and difficulty breathing. A variety of organisms, including bacteria, viruses and fungi, can cause pneumonia.
Definition. The principal signs of cerebellar dysfunction are the following: Ataxia: unsteadiness or incoordination of limbs, posture, and gait. A disorder of the control of force and timing of movements leading to abnormalities of speed, range, rhythm, starting, and stopping.
This procedure describes one of the most versatile approaches to the anterior skull base for large tumors of the sinonasal cavity. It may be used with or without a craniofacial resection. The benefits of this approach are: wide access around the tumor; good postoperative cosmesis; & decreased operative & postoperative morbidity. We have used this approach for many bilateral tumors of the nasal & sinus cavities that approach &/or invade the skull base & brain. This video show the resection of a large esthesioneuroblastoma.
Open heart (coronary artery bypass, or CABG) surgery is performed in order to reroute, or "bypass," blood around blocked arteries, thereby improving the supply of oxygen-rich blood to the heart. Surgeons usually use an artery from the chest wall to construct the "detour" around the blocked part of the artery. Veins from the legs are also used.
Gastroesophageal reflux disease (GERD) is a chronic digestive disease. GERD occurs when stomach acid or, occasionally, stomach content, flows back into your food pipe (esophagus). The backwash (reflux) irritates the lining of your esophagus and causes GERD. Both acid reflux and heartburn are common digestive conditions that many people experience from time to time. When these signs and symptoms occur at least twice each week or interfere with your daily life, or when your doctor can see damage to your esophagus, you may be diagnosed with GERD. Most people can manage the discomfort of GERD with lifestyle changes and over-the-counter medications. But some people with GERD may need stronger medications, or even surgery, to reduce symptoms.
The Spirotome belongs to the Direct & Frontal type of biopsy systems for taking large core biopsy from virtually every soft tissue in the body. The FDA has approved 13 applications. This video shows how easy it is to take a large core from a thoracic wall tumor mass. The size and quality of the sample allows quantitative molecular biology.