What is Cataract

Cataract is a clouding that develops in the crystalline lens of the eye or in its envelope, varying in degree from slight to complete opacity and obstructing the passage of light. Early in the development of age-related cataract the power of the lens may be increased, causing near-sightedness (myopia), and the gradual yellowing and opacification of the lens may reduce the perception of blue colours. Cataracts typically progress slowly to cause vision loss and are potentially blinding if untreated.
Senile cataract, occurring in the aged, is characterized by an initial opacity in the lens, subsequent swelling of the lens and final shrinkage with complete loss of transparency.







Moreover, with time the cataract cortex liquefies to form a milky white fluid in a Morgagnian cataract, which can cause severe inflammation if the lens capsule ruptures and leaks. Untreated, the cataract can cause phacomorphic glaucoma. Very advanced cataracts with weak zonules are liable to dislocation anteriorly or posteriorly. Such spontaneous posterior dislocations (akin to the historical surgical procedure of couching) in ancient times were regarded as a blessing from the heavens, because some perception of light was restored in the cataractous patients.







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What is Cataract

Cataract is a clouding that develops in the crystalline lens of the eye or in its envelope, varying in degree from slight to complete opacity and obstructing the passage of light. Early in the development of age-related cataract the power of the lens may be increased, causing near-sightedness (myopia), and the gradual yellowing and opacification of the lens may reduce the perception of blue colours. Cataracts typically progress slowly to cause vision loss and are potentially blinding if untreated.
Senile cataract, occurring in the aged, is characterized by an initial opacity in the lens, subsequent swelling of the lens and final shrinkage with complete loss of transparency.



Moreover, with time the cataract cortex liquefies to form a milky white fluid in a Morgagnian cataract, which can cause severe inflammation if the lens capsule ruptures and leaks. Untreated, the cataract can cause phacomorphic glaucoma. Very advanced cataracts with weak zonules are liable to dislocation anteriorly or posteriorly. Such spontaneous posterior dislocations (akin to the historical surgical procedure of couching) in ancient times were regarded as a blessing from the heavens, because some perception of light was restored in the cataractous patients.



Causes



Cataracts develop from a variety of reasons, including long-term exposure to ultraviolet light, exposure to radiation, secondary effects of diseases such as diabetes, hypertension and advanced age, or trauma (possibly much earlier); they are usually a result of denaturation of lens protein. Genetic factors are often a cause of congenital cataracts and positive family history may also play a role in predisposing someone to cataracts at an earlier age, a phenomenon of "anticipation" in pre-senile cataracts.

What is Gout

Gout is caused by buildup of uric acid,Uric acid crystalls travel and accumulate in the joints,in specially in feet and legs causing pain in the legs,crystals of monosodium urate or uric acid are deposited on the articular cartilage of joints, tendons and surrounding tissues. These crystals cause inflammation and pain, both severe. If unchecked, the crystals form tophi, which can cause significant tissue damage. Gout results from a combination of elevated concentrations of uric acid and overall acidity in the bloodstream. In isolation, neither elevated uric acid (hyperuricemia) nor acidity is normally sufficient to cause gout.




Signs and symptoms






Gout is characterized by excruciating, sudden, unexpected, burning pain, as well as swelling, redness, warmth, and stiffness in the affected joint. This occurs commonly in men in their toes but can appear in other parts of the body and affects women as well. Low-grade fever may also be present. The patient usually suffers from two sources of pain. The crystals inside the joint cause intense pain whenever the affected area is moved. The inflammation of the tissues around the joint also causes the skin to be swollen, tender and sore if it is even slightly touched. For example, a blanket or even the lightest sheet draping over the affected area could cause extreme pain.








Gout usually attacks the big toe (approximately 75 percent of first attacks); however, it also can affect other joints such as the ankle, heel, instep, knee, wrist, elbow, fingers, and spine. In some cases, the condition may appear in the joints of small toes that have become immobile due to impact injury earlier in life, causing poor blood circulation that leads to gout.

Hypertension

Blood pressure or BP is the pressure exerted by the flow of blood on the walls of the arteries; it is determined by the force and amount blood pumped by the heart and by diameter of the arteries. it consist of the two components systolic pressure and diastolic pressure, these are normally 120/80 mgof mercury respectively, when the blood pressure exceed these value it leads to a condition called high blood pressure or hypertension, there are two types of hypertension primary hypertension and secondary hypertension, primary hypertension is without specific identifiable cause, secondary hypertension is elevated blood pressure that results from underlying identifiable often correctable cause, only about 5 to10 % hypertension cases are thought to result from secondary causes, the most common causes of the secondary hypertension are kidney disease ,adrenal gland disease, narrowing of the aorta and sleep apnea, Hypertension common symptoms are Headache,Dizziness,Blurred vision, and in severe cases confusion and coma are possible. Small portable instruments called a sphygmomanometer usually measure Blood pressure, It consist of an air pump, pressure gauge and rubber cuff. The instrument measures the blood pressure in units called millimeter of mercury (mmhg). A blood pressure reading of 120/80mmHg is considered normal, where as the blood pressure of 140/90mmHg or higher is considered High Blood pressure or Hypertension







Causes




Most of the secondary mechanisms associated with hypertension are generally fully understood, and are outlined at secondary hypertension. However, those associated with essential (primary) hypertension are far less understood. What is known is that cardiac output is raised early in the disease course, with total peripheral resistance (TPR) normal; over time cardiac output drops to normal levels but TPR is increased. Three theories have been proposed to explain this:

Inability of the kidneys to excrete sodium, resulting in natriuretic factors such as Atrial Natriuretic Factor being secreted to promote salt excretion with the side-effect of raising total peripheral resistance.
An overactive renin / angiotensin system leads to vasoconstriction and retention of sodium and water. The increase in blood volume leads to hypertension.
An overactive sympathetic nervous system, leading to increased stress responses.

It is also known that hypertension is highly heritable and polygenic (caused by more than one gene) and a few candidate genes have been postulated in the etiology of this condition.









Prevention:





Prevention of hypertension only goes as far as the cause; one can adjust lifestyle related causes but genetics, race, age and gender are outside the realm of change.
Modifiable factors include diet, weight-loss, exercise and stress management.
Low-sodium and low-fat diets can reduce cardiovascular risks and keep arteries clear of plaque and blood volume at normal levels.
Losing even 10% of body weight can have fantastic benefits towards health, including reversal or prevention of HTN, dropping systolic pressures several points.
Exercise maintains a healthy heart, thus healthy cardiac contractions and functions. The heart is a muscle too, working out the cardiac muscles makes the heart beat more efficiently, thus pumping blood around the body more effectively.
Stressors can negatively affect blood pressure by activating the sympathetic nervous system, thus fight or flight responses which increase heartrate and blood pressure. Chronic stress can lead to regular and frequent activation of the system and repeated high blood pressure.
Effective management of stress can reduce this particular risk.