The eyes A close up of a young person's eyes. The eyes are responsible for four-fifths of all the information our brain receives. Here you can find out a bit more about how they work, common problems that affect vision and the work Sightsavers does to treat and prevent avoidable blindness. You can also find out more about the people whose lives have been changed thanks to donations from people like you. How do eyes work? (click image to see enlarged version or click here for text alternative) Graphic of an eye with information about its different parts The images we see are made up of light reflected from the objects we look at. This light enters the eye through the cornea. Because this part of the eye is curved, it bends the light, creating an upside down image on the retina (this is eventually put the right way up by the brain). The retina is a complex part of the eye, but only the very back of it is light sensitive. This part of the retina has roughly the area of a 10p coin, and is packed with photosensitive cells called rods and cones. Cones are the cells responsible for daylight vision. There are three kinds – each responding to a different wavelength of light: red, green and blue. The cones allow us to see images in colour and detail. Rods are responsible for night vision. They are sensitive to light but not to colour. In darkness, the cones do not function at all. How do we see an image? The lens focuses the image. It can do this because it is adjustable – using muscles to change shape and help us focus on objects at different distances. The automatic focusing of the lens is a reflex response and is not controlled by the brain. Once the image is clearly focused on the sensitive part of the retina, energy in the light that makes up that image creates an electrical signal. Nerve impulses can then carry information about that image to the brain through the optic nerve.

Alzheimer's is the most common form of dementia, a general term for memory loss and other intellectual abilities serious enough to interfere with daily life. Alzheimer's disease accounts for 60 to 80 percent of dementia cases. Alzheimer's is not a normal part of aging, although the greatest known risk factor is increasing age, and the majority of people with Alzheimer's are 65 and older. But Alzheimer's is not just a disease of old age. Up to 5 percent of people with the disease have early onset Alzheimer's (also known as younger-onset), which often appears when someone is in their 40s or 50s.

Endoscopic retrograde cholangiopancreatography, or ERCP, is a specialized technique used to study the bile ducts, pancreatic duct and gallbladder. Ducts are drainage routes; the drainage channels from the liver are called bile or biliary ducts. The pancreatic duct is the drainage channel from the pancreas.

A heart attack is a medical emergency. A heart attack usually occurs when a blood clot blocks blood flow to the heart. Without blood, tissue loses oxygen and dies. Symptoms include tightness or pain in the chest, neck, back, or arms, as well as fatigue, lightheadedness, abnormal heartbeat, and anxiety. Women are more likely to have atypical symptoms than men. Treatment ranges from lifestyle changes and cardiac rehabilitation to medications, stents, and bypass surgery.

Breast lump removal is surgery to remove a lump that may be breast cancer. Tissue around the lump is also removed. This surgery is called a lumpectomy. When a noncancerous tumor such as a fibroadenoma of the breast is removed, it is often called an excisional breast biopsy, instead of a lumpectomy

Schwannomas are usually located in the angle between the cerebellum and the pons, in the back of the skull (the posterior fossa). Description Schwannomas are usually very slow-growing. Symptoms Common symptoms of Schwannoma are one-sided hearing loss and buzzing or ringing in the ear. Dizziness may also occur, although it is less common. If the tumor affects the facial nerve (the 7th cranial nerve, which is located next to the 8th cranial nerve), facial paralysis may occur. Other symptoms include difficulty in swallowing, impaired eye movement, taste disturbances, and unsteadiness. Incidence Schwannomas account for about 8% of all primary brain tumors. They typically occur in middle-aged adults, and females are twice as likely as males to have this tumor. Cause Like many tumor types, the exact cause of Schwannoma is not known. However, it is believed to occur when there is a defect in a gene that normally prevents tumors from forming. Treatment Total removal using microsurgical techniques is often possible. Stereotactic radiosurgery may be used as an alternative to surgery in some patients.

The annual incidence of primary intraspinal neoplasm is approximately five per million for females and three per million for males.[9] Spinal intradural extramedullary tumors account for two thirds of all intraspinal neoplasms and include neuromas and meningiomas.[1] Overall, meningiomas account for 25 to 46% of primary spinal neoplasms and are the second most common intradural spine tumor after neuromas.[9] Spinal meningiomas occur less frequently than intracranial ones and account for approximately 7.5 to 12.7% of all meningiomas.[25]

Mini-invasive surgical repair of a ruptured Achilles tendon

Red blood cells, which form one of the major constituents of blood, are characterized by the absence of nuclei, hence they are unable to undergo cellular division or generate new erythrocytes from old ones. This eventually leads to cell disintegration, which typically occurs 4 months after the fully developed red blood cells have been in circulation within the bloodstream. During the degeneration of the red blood cells, some components of the hemoglobin are excreted from the body while other parts are conserved.

If it gets more severe and causes symptoms, your low hemoglobin count may indicate you have anemia. A low hemoglobin count is generally defined as less than 13.5 grams of hemoglobin per deciliter (135 grams per liter) of blood for men and less than 12 grams per deciliter (120 grams per liter) for women.

What is your mental age?

An intelligence quotient (IQ) is a total score derived from one of several standardized tests designed to assess human intelligence. IQ is a number meant to measure people cognitive abilities (intelligence) in relation to their age group. An I.Q between 90 and 110 is considered average; over 120, superior. Roughly 68% of the population has an IQ between 85 and 115. The average range between 70 and 130, and represents about 95% of the population.

Nephrotic syndrome is a kidney disorder that causes your body to excrete too much protein in your urine. Nephrotic syndrome is usually caused by damage to the clusters of small blood vessels in your kidneys that filter waste and excess water from your blood. Nephrotic syndrome causes swelling (edema), particularly in your feet and ankles, and increases the risk of other health problems. Treatment for nephrotic syndrome includes treating the underlying condition that's causing it and taking medications. Nephrotic syndrome can increase your risk of infections and blood clots. Your doctor may recommend medications and dietary changes to prevent these and other complications of nephrotic syndrome.

Ehlers-Danlos syndrome is a group of disorders that affect the connective tissues that support the skin, bones, blood vessels, and many other organs and tissues. Defects in connective tissues cause the signs and symptoms of Ehlers-Danlos syndrome, which vary from mildly loose joints to life-threatening complications. Previously, there were more than 10 recognized types of Ehlers-Danlos syndrome, differentiated by Roman numerals. In 1997, researchers proposed a simpler classification that reduced the number of major types to six and gave them descriptive names: the classical type (formerly types I and II), the hypermobility type (formerly type III), the vascular type (formerly type IV), the kyphoscoliosis type (formerly type VIA), the arthrochalasia type (formerly types VIIA and VIIB), and the dermatosparaxis type (formerly type VIIC). This six-type classification, known as the Villefranche nomenclature, is still commonly used. The types are distinguished by their signs and symptoms, their underlying genetic causes, and their patterns of inheritance. Since 1997, several additional forms of the condition have been described. These additional forms appear to be rare, affecting a small number of families, and most have not been well characterized.

Iatrogenic injury to the ureter is a potentially devastating complication of modern surgery. The ureters are most often injured in gynecologic, colorectal, and vascular pelvic surgery. There is also potential for considerable ureteral injury during endoscopic procedures for ureteric pathology such as tumor or lithiasis. While maneuvers such as perioperative stenting have been touted as a means to avoid ureteral injury, these techniques have not been adopted universally, and the available literature does not make a case for their routine use. Distal ureteral injuries are best managed with ureteroneocystostomy with or without a vesico-psoas hitch. Mid-ureteral and proximal ureteral injuries can potentially be managed with ureteroureterostomy. If the distal segment is unsuitable for anastomosis then a number of techniques are available for repair including a Boari tubularized bladder flap, transureteroureterostomy, or renal autotransplantation. In rare cases renal autotransplantation or ureteral substitution with gastrointestinal segments may be warranted to re-establish urinary tract continuity. Laparoscopic and minimally invasive techniques have been employed to remedy iatrogenic ureteral injuries.

Laparoscopic use of Palmer's Point

A glucagonoma is a rare tumor of the alpha cells of the pancreas that results in the overproduction of the hormone glucagon. Alpha cell tumors are commonly associated with glucagonoma syndrome, though similar symptoms are present in cases of pseudoglucagonoma syndrome in the absence of a glucagon-secreting tumor.

Alendronate Sodium is used for the following diseases and conditions: osteoporosis, and osteogenesis imperfecta. Alendronate Sodium improves the patient's condition by performing the following functions: slowing down the bone loss and helps to keep the bones strong and less likely to break. Side effects are possible with Alendronate Sodium, but do not always occur. Some of the side effects may be rare but serious. Consult your doctor if you observe any side effects, especially if they do not go away. Alendronate Sodium may cause the following side-effects: stomach pain, constipation, diarrhea, gas, nausea, and jaw pain

Possible complications include: Cardiovascular disease. ... Nerve damage (neuropathy). ... Kidney damage (nephropathy). ... Eye damage (retinopathy). ... Foot damage. ... Skin conditions. ... Hearing impairment. ... Alzheimer's disease.

A small-bowel obstruction (SBO) is caused by a variety of pathologic processes. The leading cause of SBO in industrialized countries is postoperative adhesions (60%), followed by malignancy, Crohn disease, and hernias, although some studies have reported Crohn disease as a greater etiologic factor than neoplasia.