Human beings have five special senses, touch, hearing, smell, taste and sight. Skin, ear, nose, tongue and the eye carry out these special senses. Among these five special senses eye is given the prime importance.

We can very well understand how horrible the situation when the sense of sight is absent. Vision is the nature's greatest gift to the mankind. It is essential for carrying out many body functions. It's defects can affect the mobility, mental ability, emotional stability, productivity and social interactions of a person adversely.

All these factors jointly denote the importance of conserving vision and treating the diseases leading to blindness. Retinitis Pigmentosa is such a kind of disease, which has a genetic etiology, characterized by gradual deterioration of visual acuity and visual field, finally reaching a state of total blindness. Unfortunately, researchers have not yet found out a cure for it. It is a kind of pigmentary retinal dystrophy in absence of inflammaton, which is a diffuse disorder predominantly affecting the rod system and peripheral visual fields of the eye. It is a genetic abiotropic disease with various patterns of inheritance, presenting in early years of life usually as progressive night blindness and annular scotoma. Many a time, the disease is seen as a part of several syndromes with systemic affections and ocular associations. There has been a recent hike in the   prevalence of  R.P in the community ,but the therapeutic advances to treat it effectively  are  not at par in modern medical science. Keeping this in mind, we believe its worth to discuss the Ayuvedic perspectives in the therapeutics of   Retinitis Pigmentosa .Our inspiration to prepare this paper credits to the positive results achieved on hundreds of  R.P patients treated at our hospital.

Shalakyathanthram is a branch of science, which deals with the organs seated above the neck (jathru) and also describes the diseases which are occurring in these organs, mainly eye, ear, nose and throat. It also describes the treatments of these diseases in detail . Out of these Urdhajathrugatha rogas, Nethra rogas and their treatments are given the prime importance.

According to Susrutha, and Ashtanga Hridayam (Vagbhata) Nethra is developed from Aathma. Particularly Nethrendriyam is derived from Agnimahabhootha.

Nethra originates from all the five  mahabhoothas, predominantly from Agnimahabhootha.

In the eye mamsabhaga is formed from prithvi,  rakthabhaga is formed from agnimahabhootha, krishnabhaga is derived from vayumahabhootham, suklabhaga is derived from jalamahabhootha and the asrubhaga is formed from aakaashamahabhootha.

The diameter of nethra is 2 angula. It is round in shape and resembles a gosthanam and it is constituted by all panchamahabhoothas.

According to videha,

In the total section of the eyeball the one third portion is called   krishna mandala .The one seventh portion of  krishna mandala is called as drushti mandala.

I. Mandalas II. Sandhis III. Patalas

I. Mandalas

Mandalas are 5 in number

1. Pakshmamandala ------- circle of eye lashes

2. Varthma mandlam------- circle of eyelids

3. Sukla mandalam--------- sclera and bulbar conjunctiva

4. Krishna maandalam------cornea and iris

5. Drushti mandalam  ------ pupil, lens and retina

II. Sandhis

Junction between the mandalas are called sandhis.

Sandhis are 6 in number.

1. Pakshmavarthmagatha sandhi ---- Lid margins

2. Varthmasukla gatha sandhi ------- Fornix[superior and inferior]

3. Suklakrishnagatha sandhi --------- Limbus[sclero corneal junction]

4. Krishnadrushtigatha sandhi ------- Pupilary margine

5. Kaninika sandhi -------------------- Inner canthus

6. Apanga sandhi --------------------- Outer canthus

III. Patalas

There are 6 patalas in the eye; Two bahya patalas and 4 aabhyanthara patalas. In these  4 aabhyanthara patalas all the drustigatha rogas occur.

4 abhyanthara patalas are classified on the basis of the predominant location of Panchamahabhoothas and Dhathus.

Out of these 4 abhyanthara patalas :-

The first patala is      Thejo jalashritam

The third patala is     Medoasritham

The fourth patala is   Aasthyashritham

The ability of each indriyas to perceive their respective indriyarthas is  called as indriyarthasamyogam. Nethrendriyam performs the  function of vision through indriyarthasamyogam.

The aalochaka pitham  of eye  which is having the quality of thejogunam [Electro magnetic radiation],does the function of receiving the light rays and are converted into electrical impulses . By the action of pranavayu , then conducted   to the brain to facilitate the phenomenon of  darshanam.Alochaka pitha will continuously be getting nourished by tharpaka kapha.

Orbit

Seven bones contribute to the formation of the pear shaped orbit. Frontal, sphenoid, maxillary, palatine, zygomatic, ethmoid and lacrimal. It has a base, margin, apex and four posteriorly converging walls. The orbital cavity is directed forward, outward and slightly downward.

Apart from the eyeball, the orbit also contains the following.

Eyelids

They are movable protective coverings of the eyeball.They are made up of-

Lacrimal apparatus

Conjunctiva

Thin and transparent mucous membrane conjoining the eyelid to the globe, and its epithelium is continuous with that of cornea.Two divivisions are-

Cornea

Its shiny transparent membrane having slightly greater curvature than the rest of the globe, constitutes the anterior one-sixth of the  outer coat of the eyeball. It is formed of five layers. It is separated from the sclera at the limbus.

Most of the bending of the light rays (refraction) occurs at the cornea. The lens also bends the light but to a lesser extent. The lens does a sort of fine tuning to insure that the image is sharply focused on the retina

Sclera

Its dull white and inelastic layer which form the tough posterior five –sixth  of the outermost protective coat of the eye ball. Anteriorly it is continuous with the cornea, and posteriorly continuous with dural sheath of optic nerve.

Uveal tract

Iris

It's a thin, circular , coloured disc depending upon the amount of pigment., with a central slightly nasal perforation called pupil. It consists of fibroblast , melanocytes, blood vessels, nerves and sphincter and dilator pupillae involuntary muscles.

Pupil function

Cilliary body

It is the region beyond ora serrata, the jagged line marking the termination of the retina and the beginning of cilliary body.It is composed of circular and longitudinal involuntary muscles ,the cilliary process and lining epithelium

Choroid

The dark brown choroid, nourishing the outer part of retina extends from the margin of optic nerve to the ora serrata. Its extremely vascular and exact thickness cannot be determined.

Lens

The crystalline lens in the adult is transparent, biconvex and semisolid. It has two parts-nucleus and cortex, two surfaces anterior and posterior, two poles-anterior and posterior.

As you will see from the diagrams that follow, the purpose of the lens is to present as sharp an image on the retina as possible.

The ciliary muscle helps to change the shape of the lens. This changing of lens shape is called accommodation. The lens itself is a multilayered structure. In young people it is normally perfectly clear and quite elastic. As one ages its elasticity is reduced. As one gets older the lens can also become cloudy.