Fundus flourescein angiography (FFA) is a valuable
tool in the diagnosis and management of a large number of fundus disorders.
Basically, FFA gives information by allowing the examiner to study the changes, produced by various fundus disorders, in the flow of fluorescein dye along the vasculature of the retina and choroid. Indications. It is indicated in many disorders of ocular fundus, viz., (1) Diabetic retinopathy (2) Vascu-lar occlusions; (3) Eales’ disease. (4) Central serous retinopathy, (5) Cystoid macular oedema.
Technique.

The technique of FFA comprises of rapidly injecting 5 ml of 10 per cent solution of sterile sodium fluorescein dye in the antecubital vein and taking serial photographs (with fundus camera) of the fundus of the patient who is seated with pupils fully dilated. The fundus camera has a mechanism to use blue light (420-490 nm wavelength) for exciting the fluorescein present in blood vessels and to use yellow-green filter for receiving the fluorescent light (510-530 nm wavelength) back for photography.
The first photograph is taken after 5 seconds, then every second for next 20 seconds and every 3-5 seconds for next one minute. The last pictures are taken after 10 minutes.
Complications. FFA is comparatively a safe procedure. Minor side effects include : discoloration of skin and urine, mild nausea and rarely vomiting. Anaphylaxis or cardiorespiratory problems are extremly rare. However, a syringe filled with dexamethasone and antihistaminic drug along with other measures should be kept ready to deal with such catastrophy.
Phase of angiogram. Normal angiogram consists of following overlapping phases:
1.  Pre-arterial phase. Since the dye reaches the choroidal circulation 1 second earlier than the retinal arteries, therefore in this stage choroidal circulation is filling, without any dye in retinal arteries.
2.  Arterial phase. It starts 1 second after prearterial phase and lasts until the retinal arterioles are completely filled.

involves the complete filling of retinal arterioles and capillaries with a laminar flow along the retinal veins
4. Venous phase. In this phase veins are filling and arterioles are emptying. This phase can be subdivided into early, mid, and late venous phase.
Abnormalities detected by FFA. In the blood fluorescein is readily bound to the albumin. Normally the dye remains confined to the intravascular space due to the barriers formed by the tight junctions between the endothelial cells of retinal capillaries (in-ler blood-retinal barrier) and that between the pig-nent epithelial cells (outer blood retinal barrier).
In diseased states abnormalities in the form of lyperfluorescence and hypofluorescence may be letected on FFA. !. Hyperfluorescence. The causes are :
a)   A window defect in RPE due to atrophy shows background choroidal fluorescence.
b)  Pooling of dye under detached RPE.
c)  Pooling of dye under sensory retina after breakdown of the outer blood-retinal barrier as
occurs in central serous retinopathy (CSR).
i) Leakage of dye into the neurosensory retina due to a breakdown in inner blood-retinal barrier e.g. as seen in cystoid macular edema (CME).
e) Leakage of dye from the choroidal or retinal neovascularization e.g. as seen in cases of proliferative diabetic retinopathy, and subretinal neovascular membrane in age-related macular degeneration.

(f)   Staining i.e. long retention of dye by some tissues e.g. as seen in the presence of drusen.
(g)   Leakage of dye from optic nerve head as seen in papilledema.
2. Hypofluorescence. The causes are:
(a)   Blockage of background fluorescence due to abnormal deposits on retina e.g. as seen due to the presence of retinal haemorrhage, hard exudates and pigmented clumps.
(b)   Occlusion of retinal or choroidal vasculature, e.g. as seen in central retinal artery occlusion and occlusion of capillaries in diabetic retinopathy.
(c)   Loss of vasculature as occurs in patients with choroideremia and myopic degeneration.

Angiography

Angiography is a technique used to image the blood vessels. This technique gives the positions of block in blood vessels. The image in known as angiograph. The angiograph is taken of the organ ,and stored in a computer . a second angiograph is taken after contrast containing iodine , which is used to opaque x rays , the first image is subtracted from the second , give a clear picture of blood vessels.

In heart pumping action the atria and ventricle are contract rhythmically . The wave impulse of contraction begins every time from sa node  present in the right atrium. Which means the sa  node controls the heartbeat.  Pacemaker is the rhythmic center of pace activity.So it is known as natural pacemaker. In some cases the impulse conduction system is interrupted  , which  cause irregularity in heart beat like failure of receiving the atrial impulse by ventricle and the contraction and relaxation of atria and ventricles may change.such type of patients are provided with an artificial electronic device which is known as pacemaker. The artificial pacemaker can generate electrical pulses. . the pacemaker is placed in the upper thoracic region and having a connection with the heart. This pacemaker have a pulse generator and lithium battery. The pulse generator produces electrical pulses, a wire lead which transmits the impulse .

Sonography is based on ultrasound .the ultrasound frequency ranges from 1 to 15 mhz. this high intense ultrasound waves passed through the human body, and the returning echoes are detected. The ultrasound waves pass through the homogeneous tissue without any deflection. By when a meet a another tissue is reflected back , this reflection depends on the densities of two tissues. In clinical examination the sonographer places a scan head transducer in contact with the area to be scanned. before doing this an aqueous gel is applied between the skin and scan head to the object of interest. The ultrasound waves penetrate the body , when hit on a foreign body it reflected back, at that time the transducer functions as a receiver. The echoes generated will processed with the help of a computer , converted into a video image. The time delay between sending and receiving is calculated and we can find the location of target. Sonography is much safer than radiography, because in sonography we do not use any harmful radiations. Generally sonography is used to image the adult body it can also give the images of blood vessels.diagnostic sonography another important treatment

Due to the renal failures the blood urea level increases abnormally . in such a situation an artificial kidney is used for removing excess urea from the blood . this process in known as hemodialysis. For this the blood is taken from the artery , then it is cooled to 0 degree celcius . after this the blood is mixed with anticoagulats like heparin to prevent the coagulation of blood. and then pumped into artificial kidney. The artificial kidney have number of tubes and membranes. This membrane is a semi permible membrane , which does’t allow the macromolecules to pass through it . the fluid in the tubes have some nitrogenous waste products , namely urea, uric acid etc . these smaller components are separated by dialysis .  the blood coming out from this apparatus is then heated upto body temperature . then mixed with antiheparin and return back to the vein of the body. After mixing of antiheparin the blood regains its original coagulation power.  Hemodialysis saves lifes of number of uremic patients.Hemodialysis Process

Fertilization is a union of male and female gametes. fertilization process is very much advanced.The semen of male consists of combination of spermatozoa and accessory fluids. When sperms are deposited in vagina, the sperms starts travel through the uterus upto oviducts. The sperm fuses with the egg at oviduct. Before fusion of sperm with the egg , the egg membrane must be brake , the chemical released by the spermatozoa will collapse the egg membrane . a healthy human ejaculate 4 ml of semen which have 80 to 100 million sperms . out of these only one of the sperm entering into the egg and fuse with it. To prevent the entering of second sperm , that is preventing polyspermy a membrane is developed around the fused sperm.  The fertilization occur at the ampula of the oviduct. The structure formed after the fusion of male and female gametes known by name spindle. The spindle consists of a diploid set of chromosomes . one pair from the mother and other from the father. The spindle also known by the name zygote . the zygote undergo further cleavage .

Aromatherapy is a gentle and powerful healing treatment. It uses pure essential oils- found in different parts of plants- that positively affect our physical, emotional and mental health. These oils are made up of between 50 to 500 different chemicals that occur in nature. Certified aromatherapists usually advised a combination of massage and inhalation. For the former, a good quality carrier oil, lotion, cream or salve is used to deliver the essential oils to the areas where they are most required. For inhalation, a simmering pot, diffuser, hot tub, sauna or common cotton ball is used.

Essential oils enter our body through the skin or by smell. Molecules in the scent released by the oils are get into the blood stream either through the skin during a massage or by inhalation through the nose and lungs. To quit smoking or raise oestrogen levels in postmenopausal women for instance, medication is introduced into the body through the skin. With the help of a massage, essential oils take about half an hour to be absorbed. As for smell, its psychological changes have been well researched. Our sense of smell has, by reflex action an enormous change on the central nervous system.